Powell, Lisa M.; Wada, Roy; Krauss, Ramona C.; Wang, Youfa
2013-01-01
This paper examined the importance of household and economic contextual factors as determinants of ethnic disparities in adolescent body mass index (BMI). Individual-level data from the National Longitudinal Survey of Youth 1997 for the years 1997 through 2000 were combined with economic contextual data on food prices, outlet density and median household income. The Oaxaca–Blinder decomposition method was used to examine the factors that could help explain ethnic disparities in BMI. Ethnic differences in household demographic, parental socioeconomic status (SES), and economic contextual factors explained the majority of the male black–white (63%), male Hispanic–white (78%) and female Hispanic–white (62%) BMI gaps but less than one-half of the female black–white BMI gap (44%). We found that adding the economic contextual factors increased the explained portion of the ethnic BMI gap for both female and male adolescents: the economic contextual factors explained 28% and 38% of the black–white and Hispanic–white BMI gaps for males and 13% and 8% of the black–white and Hispanic–white BMI gaps for females, respectively. Parental SES was more important in explaining the Hispanic–white BMI gap than the black–white BMI gap for both genders, whereas neighborhood economic contextual factors were more important in explaining the male BMI gap than the female BMI gap for both black–white and Hispanic–white ethnic disparities. A significantly large portion of the ethnic BMI gap, however, remained unexplained between black and white female adolescents. PMID:22607746
Margolis, Rachel; Myrskylä, Mikko
2013-01-01
We examine how family, money, and health explain variation in life satisfaction over the life cycle across seven global regions using data from the World Values Survey. With a life domain approach, we study whether the importance of the life domains varies by region and age groups and whether the variation explained by each factor is due to the magnitude or prevalence of each factor. Globally, family, money, and health explain a substantial fraction of life satisfaction, increasing from 12 percent in young adulthood to 15 percent in mature adulthood. Health is the most important factor, and its importance increases with age. Income is unimportant above age 50. Remarkably, the contribution of family is small across ages. Across regions health is most important in the wealthier, and income in the poorer regions of the world. Family explains a substantial fraction of life satisfaction only in Western Europe and Anglophone countries. Findings highlight that the population-level importance of family, money, and health in explaining variation in life satisfaction across regions is mainly attributable to the individual-level life satisfaction differences between people of different statuses rather than differences in the distribution of various states such as poor health across regions. PMID:24796263
Minor, M A; Ermilov, S G; Philippov, D A; Prokin, A A
2016-11-01
We investigated communities of oribatid mites in five peat bogs in the north-west of the East European plain. We aimed to determine the extent to which geographic factors (latitude, separation distance), local environment (Sphagnum moss species, ground water level, biogeochemistry) and local habitat complexity (diversity of vascular plants and bryophytes in the surrounding plant community) influence diversity and community composition of Oribatida. There was a significant north-to-south increase in Oribatida abundance. In the variance partitioning, spatial factors explained 33.1 % of variability in abundance across samples; none of the environmental factors were significant. Across all bogs, Oribatida species richness and community composition were similar in Sphagnum rubellum and Sphagnum magellanicum, but significantly different and less diverse in Sphagnum cuspidatum. Sphagnum microhabitat explained 52.2 % of variability in Oribatida species richness, whereas spatial variables explained only 8.7 %. There was no distance decay in community similarity between bogs with increased geographical distance. The environmental variables explained 34.9 % of the variance in community structure, with vascular plants diversity, bryophytes diversity, and ground water level all contributing significantly; spatial variables explained 15.1 % of the total variance. Overall, only 50 % of the Oribatida community variance was explained by the spatial structure and environmental variables. We discuss relative importance of spatial and local environmental factors, and make general inferences about the formation of fauna in Sphagnum bogs.
Regional variation in health care utilization in Sweden - the importance of demand-side factors.
Johansson, Naimi; Jakobsson, Niklas; Svensson, Mikael
2018-06-04
Differences in health care utilization across geographical areas are well documented within several countries. If the variation across areas cannot be explained by differences in medical need, it can be a sign of inefficiency or misallocation of public health care resources. In this observational, longitudinal panel study we use regional level data covering the 21 Swedish regions (county councils) over 13 years and a random effects model to assess to what degree regional variation in outpatient physician visits is explained by observed demand factors such as health, demography and socio-economic factors. The results show that regional mortality, as a proxy for population health, and demography do not explain regional variation in visits to primary care physicians, but explain about 50% of regional variation in visits to outpatient specialists. Adjusting for socio-economic and basic supply-side factors explains 33% of the regional variation in primary physician visits, but adds nothing to explaining the variation in specialist visits. 50-67% of regional variation remains unexplained by a large number of observable regional characteristics, indicating that omitted and possibly unobserved factors contribute substantially to the regional variation. We conclude that variations in health care utilization across regions is not very well explained by underlying medical need and demand, measured by mortality, demographic and socio-economic factors.
ERIC Educational Resources Information Center
Bai, Yang; Saint-Maurice, Pedro F.; Welk, Gregory J.; Allums-Featherston, Kelly; Candelaria, Norma
2016-01-01
Background: To advance research on youth fitness promotion it is important to understand factors that may explain the disparities in fitness. Methods: We evaluated data from the FitnessGram NFL PLAY60 Partnership Project to examine school factors influencing aerobic capacity (AC) and body mass index (BMI) in schoolchildren. Individual observations…
Ye, Tao; Wang, Yao; Guo, Zhixing; Li, Yijia
2017-01-01
The contribution of factors including fuel type, fire-weather conditions, topography and human activity to fire regime attributes (e.g. fire occurrence, size distribution and severity) has been intensively discussed. The relative importance of those factors in explaining the burn probability (BP), which is critical in terms of fire risk management, has been insufficiently addressed. Focusing on a subtropical coniferous forest with strong human disturbance in East China, our main objective was to evaluate and compare the relative importance of fuel composition, topography, and human activity for fire occurrence, size and BP. Local BP distribution was derived with stochastic fire simulation approach using detailed historical fire data (1990-2010) and forest-resource survey results, based on which our factor contribution analysis was carried out. Our results indicated that fuel composition had the greatest relative importance in explaining fire occurrence and size, but human activity explained most of the variance in BP. This implies that the influence of human activity is amplified through the process of overlapping repeated ignition and spreading events. This result emphasizes the status of strong human disturbance in local fire processes. It further confirms the need for a holistic perspective on factor contribution to fire likelihood, rather than focusing on individual fire regime attributes, for the purpose of fire risk management.
The French republican model of integration: the theory of cohesion and the practice of exclusion.
Oberti, Marco
2008-01-01
What are the explaining factors for the wave of riots in France in November 2005? In providing some answers, this article begins by examining the practical usefulness of the French republican model of integration for social cohesion, highlighting the way its negation of other criteria, such as ethnicity, race, or religion, limit this national conception of citizenship and emphasizing these excluded factors as one of the main causes of frustration and resentment among migrant groups in France.The author compares these riots to the student movements in spring 2006 and shows some similarities as well as important differences between the explaining structural factors of these two youth-based social upheavals. One of the contributing distinctions is the experience of ethnic and racial discrimination as an important source of deep resentment. The author avoids reducing the riots simply to a clash between ethnic groups with specific ethnic interests or a class revolt. Instead, he stresses the relationship between specific social structural factors and spatial effects as the element that created the context for the riots by transforming inequalities into visible and indefensible discrimination. Several factors show that spatial aspects (in the form of segregation) are important alongside the ethnic/racial ones in explaining the riots.
A multi-scale examination of stopover habitat use by birds
Buler, J.J.; Moore, F.R.; Woltmann, S.
2007-01-01
Most of our understanding of habitat use by migrating land birds comes from studies conducted at single, small spatial scales, which may overemphasize the importance of intrinsic habitat factors, such as food availability, in shaping migrant distributions. We believe that a multi-scale approach is essential to assess the influence of factors that control en route habitat use. We determined the relative importance of eight variables, each operating at a habitat-patch, landscape, or regional spatial scale, in explaining the differential use of hardwood forests by Nearctic-Neotropical land birds during migration. We estimated bird densities through transect surveys at sites near the Mississippi coast during spring and autumn migration within landscapes with variable amounts of hardwood forest cover. At a regional scale, migrant density increased with proximity to the coast, which was of moderate importance in explaining bird densities, probably due to constraints imposed on migrants when negotiating the Gulf of Mexico. The amount of hardwood forest cover at a landscape scale was positively correlated with arthropod abundance and had the greatest importance in explaining densities of all migrants, as a group, during spring, and of insectivorous migrants during autumn. Among landscape scales ranging from 500 m to 10 km radius, the densities of migrants were, on average, most strongly and positively related to the amount of hardwood forest cover within a 5 km radius. We suggest that hardwood forest cover at this scale may be an indicator of habitat quality that migrants use as a cue when landing at the end of a migratory flight. At the patch scale, direct measures of arthropod abundance and plant community composition were also important in explaining migrant densities, whereas habitat structure was of little importance. The relative amount of fleshy-fruited trees was positively related and was the most important variable explaining frugivorous migrant density during autumn. Although constraints extrinsic to habitat had a moderate role in explaining migrant distributions, our results are consistent with the view that food availability is the ultimate factor shaping the distributions of birds during stopover. ?? 2007 by the Ecological Society of America.
Determinants of Weight Gain during the First Two Years of Life—The GECKO Drenthe Birth Cohort
Küpers, Leanne K.; L’Abée, Carianne; Bocca, Gianni; Stolk, Ronald P.; Sauer, Pieter J. J.; Corpeleijn, Eva
2015-01-01
Objectives To explain weight gain patterns in the first two years of life, we compared the predictive values of potential risk factors individually and within four different domains: prenatal, nutrition, lifestyle and socioeconomic factors. Methods In a Dutch population-based birth cohort, length and weight were measured in 2475 infants at 1, 6, 12 and 24 months. Factors that might influence weight gain (e.g. birth weight, parental BMI, breastfeeding, hours of sleep and maternal education) were retrieved from health care files and parental questionnaires. Factors were compared with linear regression to best explain differences in weight gain, defined as changes in Z-score of weight-for-age and weight-for-length over 1–6, 6–12 and 12–24 months. In a two-step approach, factors were first studied individually for their association with growth velocity, followed by a comparison of the explained variance of the four domains. Results Birth weight and type of feeding were most importantly related to weight gain in the first six months. Breastfeeding versus formula feeding showed distinct growth patterns in the first six months, but not thereafter. From six months onwards, the ability to explain differences in weight gain decreased substantially (from R2 total = 38.7% to R2 total<7%). Conclusion Birth weight and breast feeding were most important to explain early weight gain, especially in the first six months of life. After the first six months of life other yet undetermined factors start to play a role. PMID:26192417
Factors Influencing Young People's Conceptions of Environment.
ERIC Educational Resources Information Center
Loughland, Tony; Reid, Anna; Walker, Kim; Petocz, Peter
2003-01-01
Explains the importance of environmental education in schools for achieving environmental protection and improvement. Statistically examines factors that incline students to a 'relation' rather than an 'object' conception of the environment. Concludes that development of the former would seem to be an important aim of environmental education and…
Environmental factors explaining the vegetation patterns in a temperate peatland.
Pellerin, Stéphanie; Lagneau, Louis-Adrien; Lavoie, Martin; Larocque, Marie
2009-08-01
Although ombrotrophic temperate peatlands are important ecosystems for maintaining biodiversity in eastern North America, the environmental factors influencing their flora are only partly understood. The relationships between plant species distribution and environmental factors were thus studied within the oldest temperate peatland of Québec. Plant assemblages were identified by cluster analysis while CCA was used to related vegetation gradients to environmental factors. Five assemblages were identified; three typical of open bog and two characterized by more minerotrophic vegetation. Thicker peat deposit was encounter underlying the bog assemblages while higher water table level and percentage of free surface water distinguished the minerotrophic assemblages. Overall, the floristic patterns observed were spatially structured along the margins and the expanse. The most important environmental factors explaining this spatial gradient were the percentage of free surface water and the highest water-table level.
Carlisle, Daren M.; Bryant, Wade L.
2011-01-01
Many physicochemical factors potentially impair stream ecosystems in urbanizing basins, but few studies have evaluated their relative importance simultaneously, especially in different environmental settings. We used data collected in 25 to 30 streams along a gradient of urbanization in each of 6 metropolitan areas (MAs) to evaluate the relative importance of 11 physicochemical factors on the condition of algal, macroinvertebrate, and fish assemblages. For each assemblage, biological condition was quantified using 2 separate metrics, nonmetric multidimensional scaling ordination site scores and the ratio of observed/expected taxa, both derived in previous studies. Separate linear regression models with 1 or 2 factors as predictors were developed for each MA and assemblage metric. Model parsimony was evaluated based on Akaike’s Information Criterion for small sample size (AICc) and Akaike weights, and variable importance was estimated by summing the Akaike weights across models containing each stressor variable. Few of the factors were strongly correlated (Pearson |r| > 0.7) within MAs. Physicochemical factors explained 17 to 81% of variance in biological condition. Most (92 of 118) of the most plausible models contained 2 predictors, and generally more variance could be explained by the additive effects of 2 factors than by any single factor alone. None of the factors evaluated was universally important for all MAs or biological assemblages. The relative importance of factors varied for different measures of biological condition, biological assemblages, and MA. Our results suggest that the suite of physicochemical factors affecting urban stream ecosystems varies across broad geographic areas, along gradients of urban intensity, and among basins within single MAs.
Guo, Zhixing; Li, Yijia
2017-01-01
The contribution of factors including fuel type, fire-weather conditions, topography and human activity to fire regime attributes (e.g. fire occurrence, size distribution and severity) has been intensively discussed. The relative importance of those factors in explaining the burn probability (BP), which is critical in terms of fire risk management, has been insufficiently addressed. Focusing on a subtropical coniferous forest with strong human disturbance in East China, our main objective was to evaluate and compare the relative importance of fuel composition, topography, and human activity for fire occurrence, size and BP. Local BP distribution was derived with stochastic fire simulation approach using detailed historical fire data (1990–2010) and forest-resource survey results, based on which our factor contribution analysis was carried out. Our results indicated that fuel composition had the greatest relative importance in explaining fire occurrence and size, but human activity explained most of the variance in BP. This implies that the influence of human activity is amplified through the process of overlapping repeated ignition and spreading events. This result emphasizes the status of strong human disturbance in local fire processes. It further confirms the need for a holistic perspective on factor contribution to fire likelihood, rather than focusing on individual fire regime attributes, for the purpose of fire risk management. PMID:28207837
Bennett, Kate Mary; Windle, Gillian
2015-01-01
Little work has focused on resilience amongst older adults, and few factors have been identified that promote their resilience. Kalisch et al. suggest that socioenvironmental factors are distant influences. We argue, however, that community and societal influences are as important as individual ones. Further, an ecological framework explains why some older adults are resilient whilst others are not.
Access to High Quality Teachers for All Students. Information Brief
ERIC Educational Resources Information Center
Mid-Atlantic Equity Center, 2009
2009-01-01
One of the most important factors in a high quality education is the knowledge, experience, and capability of the classroom teacher. There is strong evidence that having a high-quality teacher affects learning and is an important factor in explaining student test score gains (Clotfelter, Ladd, & Vigdor, 2007; Darling-Hammond, 2000;…
[Nutrigenetics and nutrigenomics].
Svacina, S
2007-01-01
According to WHO reports diet factors influence occurrence of more than 2/3 of diseases. Most of these factors belong to the categories of nutrigenetics a nutrigenomics. Nutrigenetics concerns individual differences in the reaction to food based on the genetic factors. Nutrigenomics analyses direct influences of nutrients on gene expression. Both terms are explained in our review article. Importance of nutritional factors is explained on differences of epidemiology of the same disease in different countries and on the examples of interaction of nutrition and genes for hypertension, atherosclerosis and cancer. In the future both, nutrigenetics a nutrigenomics, will induce many changes in preventive and also in clinical medicine.
Hart, Carole; McCartney, Gerry; Gruer, Laurence; Watt, Graham
2015-10-01
We aimed to identify which personal and parental factors best explained all-cause mortality and cardiovascular disease (CVD). In 1996, data were collected on 2338 adult offspring of the participants in the 1972-1976 Renfrew and Paisley prospective cohort study. Recorded risk factors were assigned to 5 groups: mid-life biological and behavioural (BB), mid-life socioeconomic, parental BB, early-life socioeconomic and parental lifespan. Participants were followed up for mortality and hospital admissions to the end of 2011. Cox proportional hazards models were used to analyse how well each group explained all-cause mortality or CVD. Akaike's Information Criterion (AIC), a measure of goodness-of-fit, identified the most important groups. For all-cause mortality (1997 participants with complete data, 111 deaths), decreases in AIC from the null model (adjusting for age and sex) to models including mid-life BB, mid-life socioeconomic, parental BB, early-life socioeconomic and parental lifespan were 55.8, 21.6, 10.3, 7.3 and 5.9, respectively. For the CVD models (1736 participants, 276 with CVD), decreases were 37.8, 3.7, 6.7, 17.3 and 0.4. Mid-life BB factors were the most important for both all-cause mortality and CVD; mid-life socioeconomic factors were important for all-cause mortality, and early-life socioeconomic factors were important for CVD. Parental lifespan was the weakest factor. As mid-life BB risk factors best explained all-cause mortality and CVD, continued action to reduce these is warranted. Targeting adverse socioeconomic factors in mid-life and early life may contribute to reducing all-cause mortality and CVD risk, respectively. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Setting of Classroom Environments for Hearing Impaired Children
ERIC Educational Resources Information Center
Turan, Zerrin
2007-01-01
This paper aims to explain effects of acoustical environments in sound perception of hearing impaired people. Important aspects of sound and hearing impairment are explained. Detrimental factors in acoustic conditions for speech perception are mentioned. Necessary acoustic treatment in classrooms and use of FM systems to eliminate these factors…
Structure of the Epiphyte Community in a Tropical Montane Forest in SW China
Zhao, Mingxu; Geekiyanage, Nalaka; Xu, Jianchu; Khin, Myo Myo; Nurdiana, Dian Ridwan; Paudel, Ekananda; Harrison, Rhett Daniel
2015-01-01
Vascular epiphytes are an understudied and particularly important component of tropical forest ecosystems. However, owing to the difficulties of access, little is known about the properties of epiphyte-host tree communities and the factors structuring them, especially in Asia. We investigated factors structuring the vascular epiphyte-host community and its network properties in a tropical montane forest in Xishuangbanna, SW China. Vascular epiphytes were surveyed in six plots located in mature forests. Six host and four micro-site environmental factors were investigated. Epiphyte diversity was strongly correlated with host size (DBH, diameter at breast height), while within hosts the highest epiphyte diversity was in the middle canopy and epiphyte diversity was significantly higher in sites with canopy soil or a moss mat than on bare bark. DBH, elevation and stem height explained 22% of the total variation in the epiphyte species assemblage among hosts, and DBH was the most important factor which alone explained 6% of the variation. Within hosts, 51% of the variation in epiphyte assemblage composition was explained by canopy position and substrate, and the most important single factor was substrate which accounted for 16% of the variation. Analysis of network properties indicated that the epiphyte host community was highly nested, with a low level of epiphyte specialization, and an almost even interaction strength between epiphytes and host trees. Together, these results indicate that large trees harbor a substantial proportion of the epiphyte community in this forest. PMID:25856457
Determinants of Internet use as a preferred source of information on personal health.
Lemire, Marc; Paré, Guy; Sicotte, Claude; Harvey, Charmian
2008-11-01
To understand the personal, social and cultural factors likely to explain recourse to the Internet as a preferred source of personal health information. A cross-sectional survey was conducted among a population of 2923 Internet users visiting a firmly established website that offers information on personal health. Multiple regression analysis was performed to identify the determinants of site use. The analysis template comprised four classes of determinants likely to explain Internet use: beliefs, intentions, user satisfaction and socio-demographic characteristics. Seven-point Likert scales were used. An analysis of the psychometric qualities of the variables provided compelling evidence of the construct's validity and reliability. A confirmatory factor analysis confirmed the correspondence with the factors predicted by the theoretical model. The regression analysis explained 35% of the variance in Internet use. Use was directly associated with five factors: perceived usefulness, importance given to written media in searches for health information, concern for personal health, importance given to the opinions of physicians and other health professionals, and the trust placed in the information available on the site itself. This study confirms the importance of the credibility of information on the frequency of Internet use as a preferred source of information on personal health. It also shows the potentially influential role of the Internet in the development of personal knowledge of health issues.
A study into psychosocial factors as predictors of work-related fatigue.
Rahman, Hanif Abdul; Abdul-Mumin, Khadizah; Naing, Lin
2016-07-14
To explore and determine relationship between psychosocial factors and work-related fatigue among emergency and critical care nurses in Brunei. Cross-sectional study conducted on all emergency and critical care nurses across Brunei public hospitals from February to April 2016. 201 nurses participated in the study (82% response rate). A total of 36% of the variance of chronic fatigue was explained by stress, trust in management, decision latitude, self-rated health, and work-family conflict. Burnout, self-rated health, commitment to workplace, and trust in management explained 30% of the variance of acute fatigue. Stress, work-family conflict and reward explained 28% of the variance of intershift recovery after controlling for significant sociodemographic variables. Smoking was identified as an important sociodemographic factor for work-related fatigue. Psychosocial factors were good predictors of work-related fatigue. A range of psychosocial factors were established, however more research is required to determine all possible causation factors of nurses' work-related fatigue.
Baldissera, Ronei; Rodrigues, Everton N L; Hartz, Sandra M
2012-01-01
The distribution of beta diversity is shaped by factors linked to environmental and spatial control. The relative importance of both processes in structuring spider metacommunities has not yet been investigated in the Atlantic Forest. The variance explained by purely environmental, spatially structured environmental, and purely spatial components was compared for a metacommunity of web spiders. The study was carried out in 16 patches of Atlantic Forest in southern Brazil. Field work was done in one landscape mosaic representing a slight gradient of urbanization. Environmental variables encompassed plot- and patch-level measurements and a climatic matrix, while principal coordinates of neighbor matrices (PCNMs) acted as spatial variables. A forward selection procedure was carried out to select environmental and spatial variables influencing web-spider beta diversity. Variation partitioning was used to estimate the contribution of pure environmental and pure spatial effects and their shared influence on beta-diversity patterns, and to estimate the relative importance of selected environmental variables. Three environmental variables (bush density, land use in the surroundings of patches, and shape of patches) and two spatial variables were selected by forward selection procedures. Variation partitioning revealed that 15% of the variation of beta diversity was explained by a combination of environmental and PCNM variables. Most of this variation (12%) corresponded to pure environmental and spatially environmental structure. The data indicated that (1) spatial legacy was not important in explaining the web-spider beta diversity; (2) environmental predictors explained a significant portion of the variation in web-spider composition; (3) one-third of environmental variation was due to a spatial structure that jointly explains variation in species distributions. We were able to detect important factors related to matrix management influencing the web-spider beta-diversity patterns, which are probably linked to historical deforestation events.
Factors Contributing to the Academic Excellence of American Jewish and Asian Students.
ERIC Educational Resources Information Center
Fejgin, Naomi
1995-01-01
Examines factors that contribute to the academic excellence of Jewish and Asian students. Finds that traditional socioeconomic measures explain some of the advantage of Jewish and Asian students over other ethnic groups but that parent and student attitudes toward education is also an important factor. (ACM)
Ferraguti, Martina; Martínez-de la Puente, Josué; Bensch, Staffan; Roiz, David; Ruiz, Santigo; Viana, Duarte S; Soriguer, Ramón C; Figuerola, Jordi
2018-05-01
Vector and host communities, as well as habitat characteristics, may have important but different impacts on the prevalence, richness and evenness of vector-borne parasites. We investigated the relative importance of (1) the mosquito community composition, (2) the vertebrate community composition and (3) landscape characteristics on the prevalence, richness and evenness of avian Plasmodium. We hypothesized that parasite prevalence will be more affected by vector-related parameters, while host parameters should be also important to explain Plasmodium richness and evenness. We sampled 2,588 wild house sparrows (Passer domesticus) and 340,829 mosquitoes, and we performed vertebrate censuses at 45 localities in the Southwest of Spain. These localities included urban, rural and natural landscapes that were characterized by several habitat variables. Twelve Plasmodium lineages were identified in house sparrows corresponding to three major clades. Variation partitioning showed that landscape characteristics explained the highest fraction of variation in all response variables (21.0%-44.8%). Plasmodium prevalence was in addition explained by vector-related variables (5.4%) and its interaction with landscape (10.2%). Parasite richness and evenness were mostly explained by vertebrate community-related variables. The structuring role of landscape characteristics in vector and host communities was a key factor in determining parasite prevalence, richness and evenness, although the role of each factor differed according to the parasite parameters studied. These results show that the biotic and abiotic contexts are important to explain the transmission dynamics of mosquito-borne pathogens in the wild. © 2018 The Authors. Journal of Animal Ecology © 2018 British Ecological Society.
Happiness among Adolescent Students in Thailand: Family and Non-Family Factors
ERIC Educational Resources Information Center
Gray, Rossarin Soottipong; Chamratrithirong, Aphichat; Pattaravanich, Umaporn; Prasartkul, Pramote
2013-01-01
This paper explores family and non-family factors contributing to happiness among students aged 15-18 in Thailand. Data come from the Social and Cultural Situation and Mental Health Survey (n = 905). Based on regression analysis, family factors are more important than non- family factors in explaining the variations in adolescents' happiness.…
Patterns of Newspaper Readership among Teenagers.
ERIC Educational Resources Information Center
Cobb, Cathy J.
1986-01-01
Identifies four groups of readers (heavy, sporadic, scanner, and apathetic) and classifies them on the basis of individual, environmental, and stimulus factors. Emphasizes the importance of environmental factors (time, peer influence, parental reading habits, etc.) in explaining differences in adolescent newspaper readership. (PD)
Hannon, Brenda
2014-01-01
To-date, studies have examined simultaneously the relative predictive powers of two or three factors on GPA. The present study examines the relative powers of five social/personality factors, five cognitive/learning factors, and SAT scores to predict freshmen and non-freshmen (sophomores, juniors, seniors) academic success (i.e., GPA). The results revealed many significant predictors of GPA for both freshmen and non-freshmen. However, subsequent regressions showed that only academic self-efficacy, epistemic belief of learning, and high-knowledge integration explained unique variance in GPA (19%-freshmen, 23.2%-non-freshmen). Further for freshmen, SAT scores explained an additional unique 10.6% variance after the influences attributed to these three predictors was removed whereas for non-freshmen, SAT scores failed to explain any additional variance. These results highlight the unique and important contributions of academic self-efficacy, epistemic belief of learning and high-knowledge integration to GPA beyond other previously-identified predictors. PMID:25568884
ERIC Educational Resources Information Center
Palos, Ramona; Gunaru, Simona Alexandra
2017-01-01
Previous research highlights that personal factors are more important than contextual factors in explaining teachers' behaviours in relation to learning participation. The present study explores the relationship between two personal factors (dispositional resistance to change and teachers' attitude towards continuing education) and the moderating…
Emotional abilities as predictors of risky driving behavior among a cohort of middle aged drivers.
Arnau-Sabatés, Laura; Sala-Roca, Josefina; Jariot-Garcia, Mercè
2012-03-01
The aim of this study is to analyze the relationship between emotional abilities and the influence of this relationship on self reported drivers' risky attitudes. The risky driving attitudes and emotional abilities of 177 future driving instructors were measured. The results demonstrate that risky attitudes correlate negatively with emotional abilities. Regression analysis showed that adaptability and interpersonal abilities explained the differences observed in the global risk attitude index. There were some differences in the specific risk factors. The variability observed in the speed and distraction and fatigue factors could also be explained by interpersonal and adaptability abilities. Nevertheless the tendency to take risks was explained by stress management and also interpersonal components. Emotional abilities have the weakest relation with alcohol and drugs factor, and in this case the variability observed was explained by the adaptability component. The results obtained highlight the importance take off including emotional abilities in prevention programs to reduce risky driving behaviors. Copyright © 2011 Elsevier Ltd. All rights reserved.
Explaining the Rise in Educational Gradients in Mortality. NBER Working Paper No. 15678
ERIC Educational Resources Information Center
Cutler, David M.; Lange, Fabian; Meara, Ellen; Richards, Seth; Ruhm, Christopher J.
2010-01-01
The long-standing inverse relationship between education and mortality strengthened substantially later in the 20th century. This paper examines the reasons for this increase. We show that behavioral risk factors are not of primary importance. Smoking has declined more for the better educated, but not enough to explain the trend. Obesity has risen…
Klanderud, Kari; Vandvik, Vigdis; Goldberg, Deborah
2015-01-01
We assessed if the relative importance of biotic and abiotic factors for plant community composition differs along environmental gradients and between functional groups, and asked which implications this may have in a warmer and wetter future. The study location is a unique grid of sites spanning regional-scale temperature and precipitation gradients in boreal and alpine grasslands in southern Norway. Within each site we sampled vegetation and associated biotic and abiotic factors, and combined broad- and fine-scale ordination analyses to assess the relative explanatory power of these factors for species composition. Although the community responses to biotic and abiotic factors did not consistently change as predicted along the bioclimatic gradients, abiotic variables tended to explain a larger proportion of the variation in species composition towards colder sites, whereas biotic variables explained more towards warmer sites, supporting the stress gradient hypothesis. Significant interactions with precipitation suggest that biotic variables explained more towards wetter climates in the sub alpine and boreal sites, but more towards drier climates in the colder alpine. Thus, we predict that biotic interactions may become more important in alpine and boreal grasslands in a warmer future, although more winter precipitation may counteract this trend in oceanic alpine climates. Our results show that both local and regional scales analyses are needed to disentangle the local vegetation-environment relationships and their regional-scale drivers, and biotic interactions and precipitation must be included when predicting future species assemblages. PMID:26091266
Klanderud, Kari; Vandvik, Vigdis; Goldberg, Deborah
2015-01-01
We assessed if the relative importance of biotic and abiotic factors for plant community composition differs along environmental gradients and between functional groups, and asked which implications this may have in a warmer and wetter future. The study location is a unique grid of sites spanning regional-scale temperature and precipitation gradients in boreal and alpine grasslands in southern Norway. Within each site we sampled vegetation and associated biotic and abiotic factors, and combined broad- and fine-scale ordination analyses to assess the relative explanatory power of these factors for species composition. Although the community responses to biotic and abiotic factors did not consistently change as predicted along the bioclimatic gradients, abiotic variables tended to explain a larger proportion of the variation in species composition towards colder sites, whereas biotic variables explained more towards warmer sites, supporting the stress gradient hypothesis. Significant interactions with precipitation suggest that biotic variables explained more towards wetter climates in the sub alpine and boreal sites, but more towards drier climates in the colder alpine. Thus, we predict that biotic interactions may become more important in alpine and boreal grasslands in a warmer future, although more winter precipitation may counteract this trend in oceanic alpine climates. Our results show that both local and regional scales analyses are needed to disentangle the local vegetation-environment relationships and their regional-scale drivers, and biotic interactions and precipitation must be included when predicting future species assemblages.
Microhabitat and Climatic Niche Change Explain Patterns of Diversification among Frog Families.
Moen, Daniel S; Wiens, John J
2017-07-01
A major goal of ecology and evolutionary biology is to explain patterns of species richness among clades. Differences in rates of net diversification (speciation minus extinction over time) may often explain these patterns, but the factors that drive variation in diversification rates remain uncertain. Three important candidates are climatic niche position (e.g., whether clades are primarily temperate or tropical), rates of climatic niche change among species within clades, and microhabitat (e.g., aquatic, terrestrial, arboreal). The first two factors have been tested separately in several studies, but the relative importance of all three is largely unknown. Here we explore the correlates of diversification among families of frogs, which collectively represent ∼88% of amphibian species. We assemble and analyze data on phylogeny, climate, and microhabitat for thousands of species. We find that the best-fitting phylogenetic multiple regression model includes all three types of variables: microhabitat, rates of climatic niche change, and climatic niche position. This model explains 67% of the variation in diversification rates among frog families, with arboreal microhabitat explaining ∼31%, niche rates ∼25%, and climatic niche position ∼11%. Surprisingly, we show that microhabitat can have a much stronger influence on diversification than climatic niche position or rates of climatic niche change.
Urben, Sébastien; Stéphan, Philippe; Habersaat, Stéphanie; Francescotti, Eric; Fegert, Jörg M; Schmeck, Klaus; Perler, Christian; Gasser, Jacques; Schmid, Marc
2017-01-01
Age of onset, callous-unemotional (CU) traits and anger dysregulation have separately been proposed as relevant factors in explaining the heterogeneity of antisocial behaviour (ASB). Taking a dimensional perspective, this study examined the specific contributions and the mutual influences (i.e., interactions) of these three characteristics on specific dimensions of ASB (i.e., criminal behaviours and externalizing symptoms). Assessments were conducted on 536 youths from institutions with the youth psychopathic traits inventory (CU traits), the Massachusetts youth screening instrument-second version (anger dysregulation), the criminology questionnaire (criminal behaviours) and the child behavior checklist (externalizing symptoms), rated by both the youths and their carers. Using Bayes as estimators, the results revealed that the number and frequency of crimes (and, more specifically, damage to property, property offenses and media crimes) were explained by a specific contribution of each factor (age of onset, CU traits and anger dysregulation). Additionally, the interactions between age of onset and CU traits or anger dysregulation were relevant predictors of some types of crimes (i.e., damage to property, property offences and media crimes). Furthermore, when rated by youths, externalizing symptoms were explained by CU traits and anger dysregulation. However, when rated by the carer, anger dysregulation was more important in explaining externalizing symptoms. This study highlights the importance of considering these factors altogether and the value of using a dimensional perspective when examining the structure of ASB in youths. Consequently, future classifications should take into account the mutual account of these characteristics, which were previously studied separately.
Jiang, Xia; Frisell, Thomas; Askling, Johan; Karlson, Elizabeth W; Klareskog, Lars; Alfredsson, Lars; Källberg, Henrik
2015-02-01
Family history of rheumatoid arthritis (RA) is one of the strongest risk factors for developing RA, and information on family history is, therefore, routinely collected in clinical practice. However, as more genetic and environmental risk factors shared by relatives are identified, the importance of family history may diminish. The aim of this study was to determine how much of the familial risk of RA can be explained by established genetic and nongenetic risk factors. History of RA among first-degree relatives of individuals in the Epidemiological Investigation of Rheumatoid Arthritis case-control study was assessed through linkage to the Swedish Multigeneration Register and the Swedish Patient Register. We used logistic regression models to investigate the decrease in familial risk after successive adjustment for combinations of nongenetic risk factors (smoking, alcohol intake, parity, silica exposure, body mass index, fatty fish consumption, and education), and genetic risk factors (shared epitope [SE] and 76 single-nucleotide polymorphisms [SNPs]). Established nongenetic risk factors did not explain familial risk of either seropositive or seronegative RA to any significant degree. Genetic risk factors accounted for a limited proportion of the familial risk of seropositive RA (unadjusted odds ratio [OR] 4.10, SE-adjusted OR 3.72, SNP-adjusted OR 3.46, and SE and SNP-adjusted OR 3.35). Established risk factors only provided an explanation for familial risk of RA in minor part, suggesting that many (familial) risk factors remain to be identified, in particular for seronegative RA. Family history of RA therefore remains an important clinical risk factor for RA, the value of which has not yet been superseded by other information. There is thus a need for further etiologic studies of both seropositive and seronegative RA. Copyright © 2015 by the American College of Rheumatology.
Racial and Ethnic Disparities in Early Childhood Obesity.
Isong, Inyang A; Rao, Sowmya R; Bind, Marie-Abèle; Avendaño, Mauricio; Kawachi, Ichiro; Richmond, Tracy K
2018-01-01
The prevalence of childhood obesity is significantly higher among racial and/or ethnic minority children in the United States. It is unclear to what extent well-established obesity risk factors in infancy and preschool explain these disparities. Our objective was to decompose racial and/or ethnic disparities in children's weight status according to contributing socioeconomic and behavioral risk factors. We used nationally representative data from ∼10 700 children in the Early Childhood Longitudinal Study Birth Cohort who were followed from age 9 months through kindergarten entry. We assessed the contribution of socioeconomic factors and maternal, infancy, and early childhood obesity risk factors to racial and/or ethnic disparities in children's BMI z scores by using Blinder-Oaxaca decomposition analyses. The prevalence of risk factors varied significantly by race and/or ethnicity. African American children had the highest prevalence of risk factors, whereas Asian children had the lowest prevalence. The major contributor to the BMI z score gap was the rate of infant weight gain during the first 9 months of life, which was a strong predictor of BMI z score at kindergarten entry. The rate of infant weight gain accounted for between 14.9% and 70.5% of explained disparities between white children and their racial and/or ethnic minority peers. Gaps in socioeconomic status were another important contributor that explained disparities, especially those between white and Hispanic children. Early childhood risk factors, such as fruit and vegetable consumption and television viewing, played less important roles in explaining racial and/or ethnic differences in children's BMI z scores. Differences in rapid infant weight gain contribute substantially to racial and/or ethnic disparities in obesity during early childhood. Interventions implemented early in life to target this risk factor could help curb widening racial and/or ethnic disparities in early childhood obesity. Copyright © 2018 by the American Academy of Pediatrics.
School and Community Factors Involved in Chilean Students' Perception of School Safety
ERIC Educational Resources Information Center
López, Verónica; Torres-Vallejos, Javier; Villalobos-Parada, Boris; Gilreath, Tamika D.; Ascorra, Paula; Bilbao, Marian; Morales, Macarena; Carrasco, Claudia
2017-01-01
Identifying and understanding predictors of school safety perceptions is important due to its consequences for students. However, it is not clear what school-related factors most contribute to explaining students' perception of school safety, and how they relate to community-related factors such as neighborhood safety. The purpose of this study…
Chen, Yun; Svenning, Jens-Christian; Wang, Xueying; Cao, Ruofan; Yuan, Zhiliang; Ye, Yongzhong
2018-01-01
The effects of environmental and dispersal processes on macrofungi community assembly remain unclear. Further, it is not well understood if community assembly differs for different functional guilds of macrofungi, e.g., soil and rotten-wood macrofungi. In this study, using 2433 macrofungi sporocarps belonging to 217 species located within a forest dynamics plot in temperate mountain forest (China), we examined the explanatory power of topography, spatial eigenvectors (representing unknown spatial processes, e.g., dispersal), plant community, and light availability for local spatial variation in the macrofungi community through variance partitioning and partial least squares path modeling. We found spatial eigenvectors and light as the most important factors for explaining species richness and composition of macrofungi. Light was negatively correlated with species richness of macrofungi. Furthermore, species richness and composition of soil macrofungi were best explained by light, and species richness and composition of rotten-wood macrofungi were best explained by spatial eigenvectors. Woody plant community structure was not an important factor for species richness and composition of macrofungi. Our findings suggest that spatial processes, perhaps dispersal limitation, and light availability were the most important factors affecting macrofungi community in temperate deciduous broad-leaved forest. Major differences in influencing factors between soil and rotten-wood macrofungi were observed, with light as the major driver for soil macrofungi and unknown spatial processes as the major driver for rotten-wood macrofungi. These findings shed new light to the processes shaping community assembly in macrofungi in temperate deciduous broad-leaved forest and point to the potential importance of both intrinsic dynamics, such as dispersal, and external forcing, such as forest dynamics, via its effect on light availability. PMID:29410660
USING HUMAN ACTIVITY DATA IN EXPOSURE MODELS: ANALYSIS OF DISCRIMINATING FACTORS
This paper tests factors thought to be important in explaining the choices people make in where they spend time. Three aggregate locations are analyzed: outdoors, indoors, and in-vehicles for two different sample groups: a year-long (longitudinal) sample of one individual and ...
Genetic and Environmental Influences on Global Family Conflict
Horwitz, Briana N.; Neiderhiser, Jenae M.; Ganiban, Jody M.; Spotts, Erica L.; Lichtenstein, Paul; Reiss, David
2010-01-01
This study examined genetic and environmental influences on global family conflict. The sample comprised 872 same-sex pairs of twin parents, their spouses/partners and one adolescent child per twin from the Twin and Offspring Study in Sweden (TOSS). The twins, spouses and child each reported on the degree of family conflict, and there was significant agreement among the family members’ ratings. These shared perspectives were explained by one common factor, indexing global family conflict. Genetic influences explained 36% of the variance in this common factor, suggesting that twins’ heritable characteristics contribute to family conflict, via genotype-environment correlation. Nonshared environmental effects explained the remaining 64% of this variance, indicating that twins’ unique childhood and/or current family experiences also play an important role. PMID:20438198
Sia, Drissa; Onadja, Yentéma; Nandi, Arijit; Foro, Anne; Brewer, Timothy
2014-01-01
Within sub-Saharan Africa, women are disproportionately at risk for acquiring and having human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). It is important to clarify whether gender inequalities in HIV prevalence in this region are explained by differences in the distributions of HIV risk factors, differences in the effects of these risk factors or some combination of both. We used an extension of the Blinder–Oaxaca decomposition approach to explain gender inequalities in HIV/AIDS in Kenya, Lesotho and Tanzania using data from the demographic and health and AIDS indicator surveys. After adjusting for covariates using Poisson regression models, female gender was associated with a higher prevalence of HIV/AIDS in Kenya [prevalence ratio (PR) = 1.73, 95% confidence interval (CI) = 1.33, 2.23 in 2003] and Lesotho (PR = 1.39, 95% CI = 1.20, 1.62 in 2004/05), but not in Tanzania. Decomposition analyses demonstrated two distinct patterns over time. In Tanzania, the gender inequality in HIV/AIDS was explained by differences in the distributions of HIV risk factors between men and women. In contrast, in Kenya and Lesotho, this inequality was partly explained by differences in the effects across men and women of measured HIV/AIDS risk factors, including socio-demographic characteristics (age and marital status) and sexual behaviours (age at first sex); these results imply that gender inequalities in HIV/AIDS would persist in Kenya and Lesotho even if men and women had similar distributions of HIV risk factors. The production of gender inequalities may vary across countries, with inequalities attributable to the unequal distribution of risk factors among men and women in some countries and the differential effect of these factors between groups in others. These different patterns have important implications for policies to reduce gender inequalities in HIV/AIDS. PMID:24345343
Self-Interest and Volunteerism: Analysis of a Statewide Association.
ERIC Educational Resources Information Center
Passewitz, Gregory R.; Donnermeyer, Joseph F.
1989-01-01
A survey of all known Ohio maple syrup producers indicated that economic self-interest is an important factor explaining the levels of participation in the statewide association. Although maple syrup is an important source of income for many Amish, none was involved in the association. (JOW)
ERIC Educational Resources Information Center
Stürmer, Kathleen; Könings, Karen D.; Seidel, Tina
2015-01-01
Preservice teachers' professional vision is an important indicator of their initial acquisition of integrated knowledge structures within university-based teacher education. To date, empirical research investigating which factors contribute to explaining preservice teachers' professional vision is scarce. This study aims to determine which factors…
Drivers for spatial variability in agricultural soil organic carbon stocks in Germany
NASA Astrophysics Data System (ADS)
Vos, Cora; Don, Axel; Hobley, Eleanor; Prietz, Roland; Heidkamp, Arne; Freibauer, Annette
2017-04-01
Soil organic carbon is one of the largest components of the global carbon cycle. It has recently gained importance in global efforts to mitigate climate change through carbon sequestration. In order to find locations suitable for carbon sequestration, and estimate the sequestration potential, however, it is necessary to understand the factors influencing the high spatial variability of soil organic carbon stocks. Due to numerous interacting factors that influence its dynamics, soil organic carbon stocks are difficult to predict. In the course of the German Agricultural Soil Inventory over 2500 agricultural sites were sampled and their soil organic carbon stocks determined. Data relating to more than 200 potential drivers of SOC stocks were compiled from laboratory measurements, farmer questionnaires and climate stations. The aims of this study were to 1) give an overview of soil organic carbon stocks in Germany's agricultural soils, 2) to quantify and explain the influence of explanatory variables on soil organic carbon stocks. Two different machine learning algorithms were used to identify the most important variables and multiple regression models were used to explore the influence of those variables. Models for predicting carbon stocks in different depth increments between 0-100 cm were developed, explaining up to 62% (validation, 98% calibration) of total variance. Land-use, land-use history, clay content and electrical conductivity were main predictors in the topsoil, while bedrock material, relief and electrical conductivity governed the variability of subsoil carbon stocks. We found 32% of all soils to be deeply anthropogenically transformed. The influence of climate related variables was surprisingly small (≤5% of explained variance), while site variables explained a large share of soil carbon variability (46-100% of explained variance), in particular in the subsoil. Thus, the understanding of SOC dynamics at regional scale requires a thorough description of the variability in soil physical parameters. Agronomic management impact on SOC stocks is important near the soil surface, but is mainly attributable to land-use and not to other management factors on this large regional scale. The importance of historical land-use practices as well as anthropogenic soil transformations to SOC stocks highlights the need for prudent soil management and conservation policies.
Drivers of nutritional change in four South Asian countries: a dynamic observational analysis.
Headey, Derek; Hoddinott, John; Park, Seollee
2016-05-01
This paper quantifies the factors explaining long-term improvements in child height for age z-scores in Bangladesh (1996/1997-2011), India (1992/1993-2005/2006), Nepal (1997-2011) and Pakistan (1991-2013). We apply the same statistical techniques to data from a common data source from which we have extracted a set of common explanatory variables that capture 'nutrition-sensitive' factors. Three are particularly important in explaining height for age z-score changes over these timeframes: improvements in material well-being; increases in female education; and improvements in sanitation. These factors have comparable associations across all four countries. © 2016 The Authors. Maternal & Child Nutrition published by John Wiley & Sons Ltd.
Drivers of nutritional change in four South Asian countries: a dynamic observational analysis
Hoddinott, John; Park, Seollee
2016-01-01
Abstract This paper quantifies the factors explaining long‐term improvements in child height for age z‐scores in Bangladesh (1996/1997–2011), India (1992/1993–2005/2006), Nepal (1997–2011) and Pakistan (1991–2013). We apply the same statistical techniques to data from a common data source from which we have extracted a set of common explanatory variables that capture ‘nutrition‐sensitive’ factors. Three are particularly important in explaining height for age z‐score changes over these timeframes: improvements in material well‐being; increases in female education; and improvements in sanitation. These factors have comparable associations across all four countries. PMID:27187917
Factors Contributing to Teachers' Use of Computer Technology in the Classroom
ERIC Educational Resources Information Center
Gilakjani, Abbas Pourhosein
2013-01-01
There are many factors for teachers to use computer technology in their classrooms. The goal of this study is to identify some of the important factors contributing the teachers' use of computer technology. The first goal of this paper is to discuss computer self-efficacy. The second goal is to explain teaching experience. The third goal is to…
Van Dyck, Delfien; De Bourdeaudhuij, Ilse; Deliens, Tom; Deforche, Benedicte
2015-04-01
When students make the transition from high school to college or university, their physical activity (PA) levels decrease strongly. Consequently, it is of crucial importance to identify the determinants of this decline in PA. The study aims were to (1) examine changes in psychosocial factors in students during the transition from high school to college/university, (2) examine if changes in psychosocial factors and residency can predict changes in PA, and (3) investigate the moderating effects of residency on the relationship between changes in psychosocial factors and changes in PA. Between March 2008 and October 2010, 291 Flemish students participated in a longitudinal study, with baseline measurements during the final year of high school and follow-up measurements at the start of second year of college/university. At both time points, participants completed a questionnaire assessing demographics, active transportation, leisure-time sports, psychosocial variables, and residency. Repeated measures MANOVA analyses and multiple moderated hierarchic regression analyses were conducted. Modeling, self-efficacy, competition-related benefits, and health-related, external and social barriers decreased, while health-related benefits and time-related barriers increased from baseline to follow-up. Decreases in modeling and time-related barriers were associated with a decrease in active transportation (adjusted R(2) = 3.2%); residency, decreases in self-efficacy, competition-related benefits, and increases in health- and time-related barriers predicted a decrease in leisure-time sports (adjusted R(2) = 29.3%). Residency only moderated two associations between psychosocial factors and changes in PA. Residency and changes in psychosocial factors were mainly important to explain the decrease in leisure-time sports. Other factors such as distance to college/university are likely more important to explain the decrease in active transportation; these are worth exploring in future studies. Because few interactions were found, similar interventions, focusing on self-efficacy, time management, and increasing perceived benefits may be effective to increase leisure-time sports in all students.
Genetic and environmental influences on global family conflict.
Horwitz, Briana N; Neiderhiser, Jenae M; Ganiban, Jody M; Spotts, Erica L; Lichtenstein, Paul; Reiss, David
2010-04-01
This study examined genetic and environmental influences on global family conflict. The sample comprised 872 same-sex pairs of twin parents, their spouses/partners, and one adolescent child per twin from the Twin and Offspring Study in Sweden. The twins, spouses, and child each reported on the degree of family conflict, and there was significant agreement among the family members' ratings. These shared perspectives were explained by one common factor, indexing global family conflict. Genetic influences explained 36% of the variance in this common factor, suggesting that twins' heritable characteristics contribute to family conflict, via genotype-environment correlation. Nonshared environmental effects explained the remaining 64% of this variance, indicating that twins' unique childhood and/or current family experiences also play an important role. 2010 APA, all rights reserved
Herd, Pamela; Karraker, Amelia; Friedman, Elliot
2012-07-01
Understand the links between race and C-reactive protein (CRP), with special attention to gender differences and the role of class and behavioral risk factors as mediators. This study utilizes the National Social Life, Health, and Aging Project data, a nationally representative study of older Americans aged 57-85 to explore two research questions. First, what is the relative strength of socioeconomic versus behavioral risk factors in explaining race differences in CRP levels? Second, what role does gender play in understanding race differences? Does the relative role of socioeconomic and behavioral risk factors in explaining race differences vary when examining men and women separately? When examining men and women separately, socioeconomic and behavioral risk factor mediators vary in their importance. Indeed, racial differences in CRP among men aged 57-74 are little changed after adjusting for both socioeconomic and behavioral risk factors with levels 35% higher for black men as compared to white men. For women aged 57-74, however, behavioral risk factors explain 30% of the relationship between race and CRP. The limited explanatory power of socioeconomic position and, particularly, behavioral risk factors, in elucidating the relationship between race and CRP among men, signals the need for research to examine additional mediators, including more direct measures of stress and discrimination.
ERIC Educational Resources Information Center
Silberg, Judy L.; And Others
1994-01-01
Applied structural equation modeling to twin data to assess impact of genetic and environmental factors on children's behavioral and emotional functioning. Applied models to maternal ratings of behavior of 515 monozygotic and 749 dizygotic twin pairs. Importance of genetic, shared, and specific environmental factors for explaining variation was…
ERIC Educational Resources Information Center
Ruiz, Maria Jose; Bermejo, Rosario; Ferrando, Mercedes; Prieto, Maria Dolores; Sainz, Marta
2014-01-01
Introduction: Academic performance is usually generally explained by student's intelligence, although other factors such as personality and motivation also account for it. Factors associated with a more complex thought process in adolescence are also beginning to gain importance in the prediction of academic performance. Among these forms of…
Halkitis, Perry N; Green, Kelly A
2007-06-01
Data ascertained in a study of club drug use among 450 gay and bisexual men indicate that at least one class of PDE-5 (phosphodiesterase type 5 inhibitor, sildenafil [Viagra]) is used frequently in combination with club drugs such as methamphetamine, MDMA (3,4 methylenedioxymethamphetamine [ecstasy]), ketamine, cocaine, and GHB (gamma hydroxy butyrate). Patterns of sildenafil use in combination with each of the club drugs differ among key demographics including race and age. Multivariate models, controlling for demographic factors, suggest that contextual factors are key to understanding why men mix sildenafil with club drugs, although age may still be an important issue to consider. Of particular importance is the fact that use of club drugs in combination with sildenafil is strongly associated with circuit and sex parties, where a centerpiece of these environments focuses on sexual exchange. These models imply interplay between person-level and contextual factors in explaining drug use patterns and further indicate that interventions aimed at addressing illicit substance use must carefully consider the role of environmental factors in explaining behavior.
Cross-cultural and psychological issues in irritable bowel syndrome.
Sahoo, Swapnajeet; Padhy, Susanta Kumar
2017-10-01
Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal disorders encountered by gastroenterologists worldwide. Of all the etiological factors that had been postulated to explain the pathophysiology of IBS, cultural and psychological factors are unique and difficult to understand. Culture plays an important role in coloring the presentation of IBS, and many a times, it has a significant role in several treatment aspects too. Psychological aspects like personality profiles, family relationships, societal myths, and abuse in any form are equally important in the management perspectives of IBS. In this brief review, we had tried to specifically focus on these aspects in IBS and have explained the evidences in favor of these factors. Knowledge about various cross-cultural aspects and psychological factors in patients with IBS is essential for taking an appropriate history and for undertaking a holistic approach for the management of the same. A collaborative team effort by psychiatrists and gastroenterologists could help in reducing the burden of this difficult to treat functional bowel disorder. © 2017 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.
Goldstein, R.M.; Stauffer, J.C.; Larson, P.R.; Lorenz, D.L.
1996-01-01
Within the instream habitat data set, measures of habitat volume (channel width and depth) and habitat diversity were most significant in explaining the variability of the fish communities. The amount of nonagricultural land and riparian zone integrity from the terrestrial habitat data set were also useful in explaining fish community composition. Variability of mean monthly discharge and the frequency of high and low discharge events during the three years prior to fish sampling were the most influential of the hydrologic variables.The first two axes of the canonical correspondence analysis accounted for 43.3 percent of the variation in the fish community and 52.5 percent of the variation in the environmental-species relation. Water-quality indicators such as the percent of fine material in suspended sediment, minimum dissolved oxygen concentrations, minimum concentrations of dissolved organic carbon, and the range of concentrations of major ions and nutrients were the variables that were most important in the canonical correspondence analysis of water-quality data with fish. No single environmental variable or data set appeared to be more important than another in explaining variation in the fish community. The environmental factors affecting the fish communities of the Red River of the North are interrelated. For the most part, instream environmental conditions (instream habitat, hydrology, and water chemistry) appear to be more important in explaining variability in fish community composition than factors related to the agricultural nature of the basin.
Large Eddy Simulation of Supersonic Inlet Flows
1998-04-01
shock/turbulence interaction in order to identify and explain factors important in shock/boundary layer interaction. Direct numerical simulation of a... factors : increase in the adverse pressure rise (due to pm2 increasing while pcl decreases) and decrease in streamwise momentum flux (due to pc...momentum flux. Both factors make the vortex more susceptible to breakdown. This implies that if the free-stream pressure rise exceeds the axial
Halvorsen, Marie; Kierkegaard, Marie; Harms-Ringdahl, Karin; Peolsson, Anneli; Dedering, Åsa
2015-01-01
Abstract This cross-sectional study sought to identify dimensions underlying measures of impairment, disability, personal factors, and health status in patients with cervical radiculopathy. One hundred twenty-four patients with magnetic resonance imaging-verified cervical radiculopathy, attending a neurosurgery clinic in Sweden, participated. Data from clinical tests and questionnaires on disability, personal factors, and health status were used in a principal-component analysis (PCA) with oblique rotation. The PCA supported a 3-component model including 14 variables from clinical tests and questionnaires, accounting for 73% of the cumulative percentage. The first component, pain and disability, explained 56%. The second component, health, fear-avoidance beliefs, kinesiophobia, and self-efficacy, explained 9.2%. The third component including anxiety, depression, and catastrophizing explained 7.6%. The strongest-loading variables of each dimension were “present neck pain intensity,” “fear avoidance,” and “anxiety.” The three underlying dimensions identified and labeled Pain and functioning, Health, beliefs, and kinesiophobia, and Mood state and catastrophizing captured aspects of importance for cervical radiculopathy. Since the variables “present neck pain intensity,” “fear avoidance,” and “anxiety” had the strongest loading in each of the three dimensions; it may be important to include them in a reduced multidimensional measurement set in cervical radiculopathy. PMID:26091482
Halvorsen, Marie; Kierkegaard, Marie; Harms-Ringdahl, Karin; Peolsson, Anneli; Dedering, Åsa
2015-06-01
This cross-sectional study sought to identify dimensions underlying measures of impairment, disability, personal factors, and health status in patients with cervical radiculopathy. One hundred twenty-four patients with magnetic resonance imaging-verified cervical radiculopathy, attending a neurosurgery clinic in Sweden, participated. Data from clinical tests and questionnaires on disability, personal factors, and health status were used in a principal-component analysis (PCA) with oblique rotation. The PCA supported a 3-component model including 14 variables from clinical tests and questionnaires, accounting for 73% of the cumulative percentage. The first component, pain and disability, explained 56%. The second component, health, fear-avoidance beliefs, kinesiophobia, and self-efficacy, explained 9.2%. The third component including anxiety, depression, and catastrophizing explained 7.6%. The strongest-loading variables of each dimension were "present neck pain intensity," "fear avoidance," and "anxiety." The three underlying dimensions identified and labeled Pain and functioning, Health, beliefs, and kinesiophobia, and Mood state and catastrophizing captured aspects of importance for cervical radiculopathy. Since the variables "present neck pain intensity," "fear avoidance," and "anxiety" had the strongest loading in each of the three dimensions; it may be important to include them in a reduced multidimensional measurement set in cervical radiculopathy.
Sheikh, Mashhood A.; Abelsen, Birgit; Olsen, Jan A.
2016-01-01
Previous studies have shown that socio-demographic factors, childhood socioeconomic status (CSES), childhood traumatic experiences (CTEs), social support and behavioral factors are associated with health and well-being in adulthood. However, the relative importance of these factors for mental health, health, and well-being has not been studied. Moreover, the mechanisms by which CTEs affect mental health, health, and well-being in adulthood are not clear. Using data from a representative sample (n = 12,981) of the adult population in Tromsø, Norway, this study examines (i) the relative contribution of structural conditions (gender, age, CSES, psychological abuse, physical abuse, and substance abuse distress) to social support and behavioral factors in adulthood; (ii) the relative contribution of socio-demographic factors, CSES, CTEs, social support, and behavioral factors to three multi-item instruments of mental health (SCL-10), health (EQ-5D), and subjective well-being (SWLS) in adulthood; (iii) the impact of CTEs on mental health, health, and well-being in adulthood, and; (iv) the mediating role of adult social support and behavioral factors in these associations. Instrumental support (24.16%, p < 0.001) explained most of the variation in mental health, while gender (21.32%, p < 0.001) explained most of the variation in health, and emotional support (23.34%, p < 0.001) explained most of the variation in well-being. Psychological abuse was relatively more important for mental health (12.13%), health (7.01%), and well-being (9.09%), as compared to physical abuse, and substance abuse distress. The subjective assessment of childhood financial conditions was relatively more important for mental health (6.02%), health (10.60%), and well-being (20.60%), as compared to mother's and father's education. CTEs were relatively more important for mental health, while, CSES was relatively more important for health and well-being. Respondents exposed to all three types of CTEs had a more than two-fold increased risk of being mentally unhealthy (RRTotal Effect = 2.75, 95% CI: 2.19–3.10), an 89% increased risk of being unhealthy (RRTotal Effect = 1.89, 95% CI: 1.47–1.99), and a 42% increased risk of having a low level of well-being in adulthood (RRTotal Effect = 1.42, 95% CI: 1.29–1.52). Social support and behavioral factors mediate 11–18% (p < 0.01) of these effects. The study advances the theoretical understanding of how CTEs influence adult mental health, health, and well-being. PMID:27252668
Murray, Joseph; Maughan, Barbara; Menezes, Ana M B; Hickman, Matthew; MacLeod, John; Matijasevich, Alicia; Gonçalves, Helen; Anselmi, Luciana; Gallo, Erika A G; Barros, Fernando C
2015-08-01
Many low- and middle-income countries have high levels of violence. Research in high-income countries shows that risk factors in the perinatal period are significant precursors of conduct problems which can develop into violence. It is not known whether the same early influences are important in lower income settings with higher rates of violence. This study compared perinatal and sociodemographic risk factors between Brazil and Britain, and their role in explaining higher rates of conduct problems and violence in Brazil. Prospective population-based birth cohort studies were conducted in Pelotas, Brazil (N = 3,618) and Avon, Britain (N = 4,103). Eleven perinatal and sociodemographic risk factors were measured in questionnaires completed by mothers during the perinatal period. Conduct problems were measured in questionnaires completed by mothers at age 11, and violence in self-report questionnaires completed by adolescents at age 18. Conduct problems were predicted by similar risk factors in Brazil and Britain. Female violence was predicted by several of the same risk factors in both countries. However, male violence in Brazil was associated with only one risk factor, and several risk factor associations were weaker in Brazil than in Britain for both females and males. Almost 20% of the higher risk for conduct problems in Brazil compared to Britain was explained by differential exposure to risk factors. The percentage of the cross-national difference in violence explained by early risk factors was 15% for females and 8% for males. A nontrivial proportion of cross-national differences in antisocial behaviour are related to perinatal and sociodemographic conditions at the start of life. However, risk factor associations are weaker in Brazil than in Britain, and influences in other developmental periods are probably of particular importance for understanding male youth violence in Brazil. © 2014 The Authors. Journal of Child Psychology and Psychiatry published by John Wiley & Sons Ltd on behalf of Association for Child and Adolescent Mental Health.
Working mechanism of extracorporeal shockwave therapy in non-urological disciplines
NASA Astrophysics Data System (ADS)
Schaden, Wolfgang
2005-04-01
For 32 years of extracorporeal shockwave lithotripsy (ESWL) only the mechanical strength of shockwaves were of clinical interest. For use in orthopaedics, the absence of dangerous long term effects (malignant degeneration, etc.) is the only important message. The mechanical model tries to explain the effect of shock waves by the provocation of microleasions in the tissue stimulating repairing processes. First doubts on this mechanical model came up when Schaden (2001) could show, that less energy is more efficient in the treatment of non-unions. Due to the basic research of the last years knowledge increased about the microbiological effects. Under the influence of shock waves the change of permeability of cell membranes and the liberation of free radicals was reported. Also the production of nitric oxide (NO) and different growth factors like vascular endothelial growth factor (VEGF), bone morphogenetic proteins (BMP), transforming growth factor-beta 1 (TGF-b1), insulin-like growth factor-I (IGF-I) etc. was observed. The biological model tries to explain the effect of shock waves by stimulating the ingrowth of blood vessels and liberation of growth factors. Under the influence of shock waves, biological tissues seem to be able to produce important substances to initiate healing processes.
What's So Important about Music Education? Routledge Research in Education
ERIC Educational Resources Information Center
Goble, J. Scott
2012-01-01
"What's So Important About Music Education?" addresses the history of rationales provided for music education in the United States. J. Scott Goble explains how certain factors stemming from the nation's constitutional separation of church and state, its embrace of democracy and capitalism, and the rise of recording, broadcast, and computer…
Aetiology of teenage childbearing: reasons for familial effects.
Olausson, P O; Lichtenstein, P; Cnattingius, S
2000-03-01
The aims of the present study were to evaluate the contribution of the genetic and environmental factors to the risk of teenage childbearing, and to study whether life style, socio-economic conditions, and personality traits could explain possible familial effects. We linked two population-based registers: the Swedish Twin Register and the Swedish Medical Birth Register. The study covers female twin pairs born between 1953 and 1958, having their first infant before the age of 30 years (n = 1885). In order to separate familial effects from other environmental influences, and genetic effects from shared environmental effects, only complete twin pairs with known zygosity were included, in all 260 monozygotic and 370 dizygotic twin pairs. We used quantitative genetic analyses to evaluate the importance of genetic and environmental effects for liability to teenage childbearing. Logistic regression analyses were used to estimate the effects of life style, socio-economic situation, and personality on the probability of teenage childbearing, and to study whether psychosocial factors could explain possible familial effects. Fifty-nine percent (0-76%) of the variance in being a teenage mother was attributable to heritable factors; 0% (0-49%) was due to shared environmental factors; and 41% (23-67%) was explained by non-shared environmental factors. Thus, the data were consistent with the hypothesis that the familial aggregation of teenage childbearing is completely explained by genetic factors, although the alternative hypothesis that familial aggregation is entirely explained by shared environmental factors cannot be ruled out. Significant effects of smoking habits, housing conditions, and educational level were found in relation to liability to teenage childbearing. However, the familial effects on risk of teenage childbearing were not mediated through similarities in life style and socio-economic factors. When studying risk factors for teenage childbearing, it is recommended to include life style and socio-economic variables as well as information about family history of teenage childbearing. Twin Research (2000) 3, 23-27.
NASA Astrophysics Data System (ADS)
Chouchane, Hatem; Krol, Maarten; Hoekstra, Arjen
2016-04-01
Water scarcity is among the main problems faced by many societies. Growing water demands put increasing pressure on local water resources, especially in water-short countries. Virtual water trade can play a key role in filling the gap between local demands and supply. This study aims to analyze the changes in virtual water trade of Tunisia in relation to environmental and socio-economic factors such as GDP, irrigated land, precipitation, population and water scarcity. The water footprint is estimated using Aquacrop for six crops over the period 1981-2010 at daily basis and a spatial resolution of 5 by 5 arc minutes. Virtual water trade is quantified at yearly basis. Regression models are used to investigate changes in virtual water trade in relation to various environmental and socio-economic factors. The explaining variables are selected in order to help understanding the trend and the inter-annual variability of the net virtual water import; GDP, population and irrigated land are hypothesized to explain the trend, and precipitation and water scarcity to explain variability. The selected crops are divided into three baskets. The first basket includes the two most imported crops, which are mainly rain-fed (wheat and barley). The second basket contains the two most exported crops, which are both irrigated and rain-fed (olives and dates). In the last basket we find the two highest economic blue water productive crops, which are mainly irrigated (tomatoes and potatoes). The results show the impact of each factor on net virtual water import of the selected crops during the period 1981-2010. Keywords: Virtual water, trade patterns, Aquacrop, Tunisia, water scarcity, water footprint.
Pritt, Jeremy J.; Roseman, Edward F.; O'Brien, Timothy P.
2014-01-01
In his seminal work, Hjort (in Fluctuations in the great fisheries of Northern Europe. Conseil Parmanent International Pour L'Exploration De La Mar. Rapports et Proces-Verbaux, 20: 1–228, 1914) observed that fish population levels fluctuated widely, year-class strength was set early in life, and egg production by adults could not alone explain variability in year-class strength. These observations laid the foundation for hypotheses on mechanisms driving recruitment variability in marine systems. More recently, researchers have sought to explain year-class strength of important fish in the Laurentian Great Lakes and some of the hypotheses developed for marine fisheries have been transferred to Great Lakes fish. We conducted a literature review to determine the applicability of marine recruitment hypotheses to Great Lakes fish. We found that temperature, interspecific interactions, and spawner effects (abundance, age, and condition of adults) were the most important factors in explaining recruitment variability in Great Lakes fish, whereas relatively fewer studies identified bottom-up trophodynamic factors or hydrodynamic factors as important. Next, we compared recruitment between Great Lakes and Baltic Sea fish populations and found no statistical difference in factors driving recruitment between the two systems, indicating that recruitment hypotheses may often be transferable between Great Lakes and marine systems. Many recruitment hypotheses developed for marine fish have yet to be applied to Great Lakes fish. We suggest that future research on recruitment in the Great Lakes should focus on forecasting the effects of climate change and invasive species. Further, because the Great Lakes are smaller and more enclosed than marine systems, and have abundant fishery-independent data, they are excellent candidates for future hypothesis testing on recruitment in fish.
Boulware, L Ebony; Ratner, Lloyd E; Cooper, Lisa A; Sosa, Julie Ann; LaVeist, Thomas A; Powe, Neil R
2002-02-01
Recent efforts to recruit blood and organ donors have only marginally improved demographic disparities in willingness to donate. Few studies have examined which factors are most important in explaining race and gender disparities in willingness to donate. To assess race and gender differences in willingness to donate blood and cadaveric organs, and to determine the extent to which several factors (including sociodemographic characteristics and attitudes about religion and mistrust of hospitals) might explain differences in willingness to donate. Cross-sectional telephone survey of Maryland households contacted via random-digit dialing. Past blood donation, organ-donor status on driver's license, and measures of medical mistrust and religious and spiritual salience. Persons age 18 to 75 living in the Baltimore, Maryland metropolitan area. Of 385 respondents (84% of randomized households), 114 were black females, 46 were black males, 110 were white females, and 69 were white males. Before adjustment, black females were least willing to donate blood (41%), and black males were least willing to become cadaveric donors (19%) among all race-gender groups. Adjustment for respondent concerns about mistrust of hospitals and discrimination in hospitals explained most differences in willingness to donate blood, whereas adjustment for respondents' beliefs regarding the importance of spirituality and religion explained most differences in willingness to donate cadaveric organs. Both race and gender are important identifiers of those less willing to donate. To maximize efficiency, donor recruitment efforts should focus on race-gender groups with lowest levels of willingness. Potential donor concerns regarding mistrust in hospitals and religion/spirituality may serve as important issues to address when developing programs to improve donation rates.
Using Focus Groups to Study ALN Faculty Motivation
ERIC Educational Resources Information Center
Hiltz, Starr Roxanne; Shea, Peter; Kim, Eunhee
2007-01-01
What are the most significant factors that motivate and inhibit faculty with regard to teaching in online environments? And what are the specific kinds of experiences that underlie and explain the importance of these factors? One goal of this study was to add to understanding of these issues, but the primary purpose of this study is determining…
Using Focus Groups to Study ALN Faculty Motivation
ERIC Educational Resources Information Center
Hiltz, Starr Roxanne; Shea, Peter; Kim, Eunhee
2010-01-01
What are the most significant factors that motivate and inhibit faculty with regard to teaching in online environments? And what are the specific kinds of experiences that underlie and explain the importance of these factors? One goal of this study was to add to understanding of these issues, but the primary purpose of this study is determining…
ERIC Educational Resources Information Center
Wang, Shu-Tai; Chen, Cheng-Chung
2015-01-01
Learning outcome is an important indicator for educators in evaluating curriculum design. The focus of this study has been to examine the factors within internship programs, recognizing the complex nature of knowledge application in a practical industry environment. Flow theory was adopted to explain the psychological state of hospitality students…
Factor analysis of financial and operational performance measures of non-profit hospitals.
Das, Dhiman
2009-01-01
To understand the important dimensions of the financial and operational performance of non-profit hospitals. Secondary data for non-profit US hospitals between 1996 and 2004. I use iterative principal factor analysis of hospitals' financial and operational ratios for each year of the study. For factor interpretation, I use oblique rotation. Financial ratios were created using cost report data from HCRIS 2552-96 available from the Centers for Medicaid & Medicare Services (CMS). I identify five factors--capital structure, profitability, activity, liquidity, and an operational factor--that explain most of the variation in the performance of non-profit hospitals. I also find that capital structure is more important than profitability in determining the performance of these hospitals. The importance of capital structure highlights a significant shift in the organization of the non-profit hospitals' finances.
ERIC Educational Resources Information Center
Watson, Charity Noel
2012-01-01
The Black-White achievement and participation gap in mathematics is a major concern for educators in America. In order to understand why these gaps exist and have continued to exist over the years, it is important to identify some of the factors that may contribute to them. However, one of the limitations in identifying factors that influence the…
Relationships between Adaptive Behaviours, Personal Factors, and Participation of Young Children.
Killeen, Hazel; Shiel, Agnes; Law, Mary; O'Donovan, Donough J; Segurado, Ricardo; Anaby, Dana
2017-12-19
To examine the extent to which personal factors (age, socioeconomic grouping, and preterm birth) and adaptive behaviour explain the participation patterns of young children. 65 Children 2-5 years old with and without a history of preterm birth and no physical or intellectual disability were selected by convenience sampling from Galway University Hospital, Ireland. Interviews with parents were conducted using the Adaptive Behaviour Assessment System, Second Edition (ABAS-II) and the Assessment of Preschool Children's Participation (APCP). Linear regression models were used to identify associations between the ABAS-II scores, personal factors, and APCP scores for intensity and diversity of participation. Adaptive behaviour explained 21% of variance in intensity of play, 18% in intensity of Skill Development, 7% in intensity of Active Physical Recreation, and 6% in intensity of Social Activities controlling for age, preterm birth, and socioeconomic grouping. Age explained between 1% and 11% of variance in intensity of participation scores. Adapted behaviour (13%), Age (17%), and socioeconomic grouping (5%) explained a significant percentage of variance in diversity of participation controlling for the other variables. Adaptive behaviour had a unique contribution to children's intensity and diversity of participation, suggesting its importance.
Gonçalves, Gabriela Silva Ribeiro; Cerqueira, Pablo Vieira; Brasil, Leandro Schlemmer; Santos, Marcos Pérsio Dantas
2017-01-01
Understanding the processes that influence species diversity is still a challenge in ecological studies. However, there are two main theories to discuss this topic, the niche theory and the neutral theory. Our objective was to understand the importance of environmental and spatial processes in structuring bird communities within the hydrological seasons in dry forest areas in northeastern Brazil. The study was conducted in two National Parks, the Serra da Capivara and Serra das Confusões National Parks, where 36 areas were sampled in different seasons (dry, dry/rainy transition, rainy, rainy/dry transition), in 2012 and 2013. We found with our results that bird species richness is higher in the rainy season and lower during the dry season, indicating a strong influence of seasonality, a pattern also found for environmental heterogeneity. Richness was explained by local environmental factors, while species composition was explained by environmental and spatial factors. The environmental factors were more important in explaining variations in composition. Climate change predictions have currently pointed out frequent drought events and a rise in global temperature by 2050, which would lead to changes in species behavior and to increasing desertification in some regions, including the Caatinga. In addition, the high deforestation rates and the low level of representativeness of the Caatinga in the conservation units negatively affects bird communities. This scenario has demonstrated how climatic factors affect individuals, and, therefore, should be the starting point for conservation initiatives to be developed in xeric environments.
Gonçalves, Gabriela Silva Ribeiro; Cerqueira, Pablo Vieira; Brasil, Leandro Schlemmer; Santos, Marcos Pérsio Dantas
2017-01-01
Understanding the processes that influence species diversity is still a challenge in ecological studies. However, there are two main theories to discuss this topic, the niche theory and the neutral theory. Our objective was to understand the importance of environmental and spatial processes in structuring bird communities within the hydrological seasons in dry forest areas in northeastern Brazil. The study was conducted in two National Parks, the Serra da Capivara and Serra das Confusões National Parks, where 36 areas were sampled in different seasons (dry, dry/rainy transition, rainy, rainy/dry transition), in 2012 and 2013. We found with our results that bird species richness is higher in the rainy season and lower during the dry season, indicating a strong influence of seasonality, a pattern also found for environmental heterogeneity. Richness was explained by local environmental factors, while species composition was explained by environmental and spatial factors. The environmental factors were more important in explaining variations in composition. Climate change predictions have currently pointed out frequent drought events and a rise in global temperature by 2050, which would lead to changes in species behavior and to increasing desertification in some regions, including the Caatinga. In addition, the high deforestation rates and the low level of representativeness of the Caatinga in the conservation units negatively affects bird communities. This scenario has demonstrated how climatic factors affect individuals, and, therefore, should be the starting point for conservation initiatives to be developed in xeric environments. PMID:28441412
Childhood Obesity and Cognitive Achievement.
Black, Nicole; Johnston, David W; Peeters, Anna
2015-09-01
Obese children tend to perform worse academically than normal-weight children. If poor cognitive achievement is truly a consequence of childhood obesity, this relationship has significant policy implications. Therefore, an important question is to what extent can this correlation be explained by other factors that jointly determine obesity and cognitive achievement in childhood? To answer this question, we exploit a rich longitudinal dataset of Australian children, which is linked to national assessments in math and literacy. Using a range of estimators, we find that obesity and body mass index are negatively related to cognitive achievement for boys but not girls. This effect cannot be explained by sociodemographic factors, past cognitive achievement or unobserved time-invariant characteristics and is robust to different measures of adiposity. Given the enormous importance of early human capital development for future well-being and prosperity, this negative effect for boys is concerning and warrants further investigation. Copyright © 2015 John Wiley & Sons, Ltd.
Validation of ACG Case-mix for equitable resource allocation in Swedish primary health care.
Zielinski, Andrzej; Kronogård, Maria; Lenhoff, Håkan; Halling, Anders
2009-09-18
Adequate resource allocation is an important factor to ensure equity in health care. Previous reimbursement models have been based on age, gender and socioeconomic factors. An explanatory model based on individual need of primary health care (PHC) has not yet been used in Sweden to allocate resources. The aim of this study was to examine to what extent the ACG case-mix system could explain concurrent costs in Swedish PHC. Diagnoses were obtained from electronic PHC records of inhabitants in Blekinge County (approx. 150,000) listed with public PHC (approx. 120,000) for three consecutive years, 2004-2006. The inhabitants were then classified into six different resource utilization bands (RUB) using the ACG case-mix system. The mean costs for primary health care were calculated for each RUB and year. Using linear regression models and log-cost as dependent variable the adjusted R2 was calculated in the unadjusted model (gender) and in consecutive models where age, listing with specific PHC and RUB were added. In an additional model the ACG groups were added. Gender, age and listing with specific PHC explained 14.48-14.88% of the variance in individual costs for PHC. By also adding information on level of co-morbidity, as measured by the ACG case-mix system, to specific PHC the adjusted R2 increased to 60.89-63.41%. The ACG case-mix system explains patient costs in primary care to a high degree. Age and gender are important explanatory factors, but most of the variance in concurrent patient costs was explained by the ACG case-mix system.
ERIC Educational Resources Information Center
Smidt, Wilfried
2015-01-01
Academic success in early childhood teacher education is important because it provides a foundation for occupational development in terms of professional competence, the quality of educational practices, as well as career success. Consequently, identifying factors that can explain differences in academic success is an important research task.…
Wee, Christina C; Davis, Roger B; Chiodi, Sarah; Huskey, Karen W; Hamel, Mary B
2015-02-01
Patients with obesity face widespread social bias, but the importance of this social stigma to patients relative to other quality of life (QOL) factors is unclear. Our aim was to examine the importance of obesity-related social stigma relative to other QOL factors on reducing patients' overall well-being. We used a cross-sectional telephone interview. The study was conducted at four diverse primary care practices in Greater Boston. Three hundred and thirty-seven primary care patients aged 18-65 years and with a body mass index (BMI) of 35 kg/m(2) or higher participated in the study. Patients' health utility (preference-based QOL measure) was determined via responses to a series of standard gamble scenarios assessing willingness to risk death to lose various amounts of weight or to achieve perfect health. We used the Impact of Weight on Quality of Life-lite instrument to assess QOL domains specific to obesity (physical function, self-esteem, sexual life, public distress or social stigma, and work), and we examined variation in utility explained by these domains. Depending on patients' race/ethnicity, mean health utilities ranged from 0.92 to 0.99 among men and from 0.89 to 0.93 among women. After adjustment for race, BMI, and education, none of the QOL domains explained much of the variation in utility among men, except for work function among Hispanic men. In contrast, social stigma was the leading QOL contributor to utility for Caucasian women (explaining 6 % of the marginal variation beyond demographics and BMI). In contrast, sexual function was the most important contributor among African American women (3 % marginal variation), and work life was most important among Hispanic women (> 20 % in variation). Lower scores in one domain did not always translate into lower well-being. Moreover, QOL summary scores often explained less of the variation than some individual domains. Obesity-related social stigma had disproportionate adverse effects on Caucasian women patients' well-being, whereas weight-related impairment in work function was particularly important among Hispanic patients and impaired sexual function was important to diminished well-being among African American women although its impact appeared modest.
NASA Astrophysics Data System (ADS)
Novareza, O.; Sulistiyarini, D. H.; Wiradmoko, R.
2018-02-01
This paper presents the result of using Taguchi method in turning process of medium carbon steel of AISI 4140. The primary concern is to find the optimal surface roughness after turning process. The taguchi method is used to get a combination of factors and factor levels in order to get the optimum surface roughness level. Four important factors with three levels were used in experiment based on Taguchi method. A number of 27 experiments were carried out during the research and analysed using analysis of variance (ANOVA) method. The result of surface finish was determined in Ra type surface roughness. The depth of cut was found to be the most important factors for reducing the surface roughness of AISI 4140 steel. On the contrary, the other important factors i.e. spindle speed and rake side angle of the tool were proven to be less factors that affecting the surface finish. It is interesting to see the effect of coolant composition that gained the second important factors to reduce the roughness. It may need further research to explain this result.
Zwaanswijk, Wendy; Veen, Violaine C; van Geel, Mitch; Andershed, Henrik; Vedder, Paul
2017-08-01
The current study examines how the bifactor model of the Youth Psychopathic Traits Inventory (YPI) is related to conduct problems in a sample of Dutch adolescents (N = 2,874; 43% female). It addresses to what extent the YPI dimensions explain variance over and above a General Psychopathy factor (i.e., one factor related to all items) and how the general factor and dimensional factors are related to conduct problems. Group differences in these relations for gender, ethnic background, and age were examined. Results showed that the general factor is most important, but dimensions explain variance over and above the general factor. The general factor, and Affective and Lifestyle dimensions, of the YPI were positively related to conduct problems, whereas the Interpersonal dimension was not, after taking the general factor into account. However, across gender, ethnic background, and age, different dimensions were related to conduct problems over and above the general factor. This suggests that all 3 dimensions should be assessed when examining the psychopathy construct. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
ERIC Educational Resources Information Center
Bradley, Deirdre Elyse
2015-01-01
A reasoned action approach (RAA) was used to assess the importance of psychological factors (attitude, perceived norm, and perceived behavioral control) in forming a woman's intention to use mobile technology, specifically mobile business applications. This study also examined whether the significance of these factors varied across cultures. An…
ERIC Educational Resources Information Center
Nair, Pradeep Kumar; Ali, Faizan; Leong, Lim Chee
2015-01-01
Purpose: This study aims to explain the factors affecting students' acceptance and usage of a lecture capture system (LCS)--ReWIND--in a Malaysian university based on the extended unified theory of acceptance and use of technology (UTAUT2) model. Technological advances have become an important feature of universities' plans to improve the…
Wheelock, Ana; Miraldo, Marisa; Thomson, Angus; Vincent, Charles; Sevdalis, Nick
2017-01-01
Objectives Despite continuous efforts to improve influenza vaccination coverage, uptake among high-risk groups remains suboptimal. We aimed to identify policy amenable factors associated with vaccination and to measure their importance in order to assist in the monitoring of vaccination sentiment and the design of communication strategies and interventions to improve vaccination rates. Setting The USA, the UK and France. Participants A total of 2412 participants were surveyed across the three countries. Outcome measures Self-reported influenza vaccination. Methods Between March and April 2014, a stratified random sampling strategy was employed with the aim of obtaining nationally representative samples in the USA, the UK and France through online databases and random-digit dialling. Participants were asked about vaccination practices, perceptions and feelings. Multivariable logistic regression was used to identify factors associated with past influenza vaccination. Results The models were able to explain 64%–80% of the variance in vaccination behaviour. Overall, sociopsychological variables, which are inherently amenable to policy, were better at explaining past vaccination behaviour than demographic, socioeconomic and health variables. Explanatory variables included social influence (physician), influenza and vaccine risk perceptions and traumatic childhood experiences. Conclusions Our results indicate that evidence-based sociopsychological items should be considered for inclusion into national immunisation surveys to gauge the public’s views, identify emerging concerns and thus proactively and opportunely address potential barriers and harness vaccination drivers. PMID:28706088
Paulus, Daniel J; Talkovsky, Alexander M; Heggeness, Luke F; Norton, Peter J
2015-01-01
Negative affectivity (NA) has been linked to anxiety and depression (DEP). Identifying the common factors between anxiety and DEP is important when explaining their overlap and comorbidity. However, general factors such as NA tend to have differential relationships with different disorders, suggesting the need to identify mediators in order to explicate these relationships. The current study tests a theoretically and empirically derived hierarchical model of emotional disorders including both a general factor (NA) and transdiagnostic risk factors [anxiety sensitivity (AS) and intolerance of uncertainty (IoU)] using structural equation modeling. AS was tested as a mid-level factor between NA and panic disorder/agoraphobia, while IoU was tested as a mid-level factor between NA and social phobia, generalized anxiety disorder, obsessive-compulsive disorder, and DEP. Data from 642 clinical outpatients with a heterogeneous presentation of emotional disorders were available for analysis. The hierarchical model fits the data adequately. Moreover, while a simplified model removing AS and IoU fits the data well, it resulted in a significant loss of information for all latent disorder constructs. Data were unavailable to estimate post-traumatic stress disorder or specific phobias. Future work will need to extend to other emotional disorders. This study demonstrates the importance of both general factors that link disorders together and semi-specific transdiagnostic factors partially explaining their heterogeneity. Including these mid-level factors in hierarchical models of psychopathology can help account for additional variance and help to clarify the relationship between disorder constructs and NA.
Ekbäck, Gunnar; Åstrøm, Anne Nordrehaug; Klock, Kristin; Ordell, Sven; Unell, Lennart
2012-07-01
The aims of this study were to identify explanatory factors of satisfaction with oral health among Norwegian and Swedish 65 year olds in terms of items from four different domains of ICF and to compare the strengths of the various ICF domains in explaining satisfaction with oral health. Further it was to assess whether the explanatory factors of ICF domains vary between Norway and Sweden. In 2007, standardized questionnaires were mailed to all the residents in certain counties of Sweden and Norway who were born in 1942. Response rates were 73.1% (n = 6078) in Sweden and 56.0% (n = 4062) in Norway. In total, 33 questions based on four different ICF domains were chosen to explain satisfaction with oral health. Logistic regression showed that four different ICF domains in terms of body function, body structure, activity/participation and environmental factors explained, respectively, 53%, 31%, 12% and 34% of the explanatory variance in the satisfaction with oral health. In the final analysis, only nine items were statistically significant (p < 0.05). This study indicates that ICF as a conceptual model could cover a broad spectrum of factors embedded in OHRQoL measured by a global question in Sweden and Norway. Nine items, representing four ICF domains, were important in the final model for explaining satisfaction with oral health.
Goings, Trenette Clark; Butler-Bente, Emily; McGovern, Tricia; Howard, Matthew O.
2016-01-01
Most substance-use prevention interventions are based on the implicit assumption that risk and protective factors for substance use are the same for biracial and monoracial youth. However, preliminary research suggests this assumption may be untrue. This study compared the prevalence and correlates of substance use among Black, White, and biracial Black-White youth. Data were derived from the National Longitudinal Study of Adolescent and Adult Health (Add Health), which is a longitudinal investigation using stratified random sampling to study health behaviors. After controlling for sociodemographic factors and using weighted Poisson and logistic regression, we found the substance-use prevalence rates of Black-White youth to be intermediate to the higher rates of Whites and lower rates of Blacks. In addition, Black-White youth’s scores on most covariates were intermediate to those of the monoracial groups. Family factors were more important in explaining higher substance use than other contextual factors. School factors seem to be important in explaining lower substance use for Black-White youth. Correlates of substance use for Black-White youth were not identical to those of either Black or White youth. More research on the observed intermediate phenomena among biracial youth vis-à-vis prevalence, correlates, and causes of substance use is needed. PMID:27427812
Yan, Hai-Fei; Zhang, Cai-Yun; Anderberg, Arne A; Hao, Gang; Ge, Xue-Jun; Wiens, John J
2018-04-17
What causes the disparity in biodiversity among regions is a fundamental question in biogeography, ecology, and evolutionary biology. Evolutionary and biogeographic processes (speciation, extinction, dispersal) directly determine species richness patterns, and can be studied using integrative phylogenetic approaches. However, the strikingly high richness of East Asia relative to other Northern Hemisphere regions remains poorly understood from this perspective. Here, for the first time, we test two general hypotheses (older colonization time, faster diversification rate) to explain this pattern, using the plant tribe Lysimachieae (Primulaceae) as a model system. We generated a new time-calibrated phylogeny for Lysimachieae (13 genes, 126 species), to estimate colonization times and diversification rates for each region and to test the relative importance of these two factors for explaining regional richness patterns. We find that neither time nor diversification rates alone explain richness patterns among regions in Lysimachieae. Instead, a new index that combines both factors explains global richness patterns in the group and their high East Asian biodiversity. Based on our results from Lysimachieae, we suggest that the high richness of plants in East Asia may be explained by a combination of older colonization times and faster diversification rates in this region. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.
Influence of cognition and symptoms of schizophrenia on IADL performance.
Lipskaya, Lena; Jarus, Tal; Kotler, Moshe
2011-09-01
People with schizophrenia experience difficulties with instrumental activities of daily living (IADL), which are required for independent living. Yet, factors that influence IADL performance are still poorly understood. Identification of such factors will contribute to the rehabilitation process and recovery. The present study aimed to examine the influence of cognitive abilities, schizophrenia symptoms, and demographic variables on IADL functioning during acute hospital admission. The participants were 81 adults with DSM-IV chronic schizophrenia. They were assessed on the Revised Observed Tasks of Daily Living (OTDL-R), the Positive and Negative Syndrome Scale (PANSS), the Neurobehavioral Cognitive Status Examination (Cognistat), and the Kitchen Task Assessment (KTA) at acute hospitalization. The prediction model of IADL performance at this time consists of executive functioning (explained 21% of variance), memory and abstract thinking (explained 13.5%), negative symptoms (explained 13%), age of illness onset and years of education (explained 8%). The total explained variance is 53.5%. These results provide evidence-based guidelines for the evaluation process in inpatient settings. Such guidelines are important since planning of intervention processes and appropriate community integration programs often occurs during acute hospitalization, while the structured nature of inpatient settings limits natural variability in occupational performance.
Kulasegaram, Kulamakan M; Grierson, Lawrence E M; Norman, Geoffrey R
2013-10-01
Medical education research focuses extensively on experience and deliberate practice (DP) as key factors in the development of expert performance. The research on DP minimises the role of individual ability in expert performance. This claim ignores a large body of research supporting the importance of innate individual cognitive differences. We review the relationship between DP and an innate individual ability, working memory (WM) capacity, to illustrate how both DP and individual ability predict expert performance. This narrative review examines the relationship between DP and WM in accounting for expert performance. Studies examining DP, WM and individual differences were identified through a targeted search. Although all studies support extensive DP as a factor in explaining expertise, much research suggests individual cognitive differences, such as WM capacity, predict expert performance after controlling for DP. The extent to which this occurs may be influenced by the nature of the task under study and the cognitive processes used by experts. The importance of WM capacity is greater for tasks that are non-routine or functionally complex. Clinical reasoning displays evidence of this task-dependent importance of individual ability. No single factor is both necessary and sufficient in explaining expertise, and individual abilities such as WM can be important. These individual abilities are likely to contribute to expert performance in clinical settings. Medical education research and practice should identify the individual differences in novices and experts that are important to clinical performance. © 2013 John Wiley & Sons Ltd.
Explaining ethnic disparities in lung function among young adults: A pilot investigation
Patel, Jaymini; Minelli, Cosetta; Burney, Peter G. J.
2017-01-01
Background Ethnic disparities in lung function have been linked mainly to anthropometric factors but have not been fully explained. We conducted a cross-sectional pilot study to investigate how best to study ethnic differences in lung function in young adults and evaluate whether these could be explained by birth weight and socio-economic factors. Methods We recruited 112 university students of White and South Asian British ethnicity, measured post-bronchodilator lung function, obtained information on respiratory symptoms and socio-economic factors through questionnaires, and acquired birth weight through data linkage. We regressed lung function against ethnicity and candidate predictors defined a priori using linear regression, and used penalised regression to examine a wider range of factors. We reviewed the implications of our findings for the feasibility of a larger study. Results There was a similar parental socio-economic environment and no difference in birth weight between the two ethnic groups, but the ethnic difference in FVC adjusted for sex, age, height, demi-span, father’s occupation, birth weight, maternal educational attainment and maternal upbringing was 0.81L (95%CI: -1.01 to -0.54L). Difference in body proportions did not explain the ethnic differences although parental immigration was an important predictor of FVC independent of ethnic group. Participants were comfortable with study procedures and we were able to link birth weight data to clinical measurements. Conclusion Studies of ethnic disparities in lung function among young adults are feasible. Future studies should recruit a socially more diverse sample and investigate the role of markers of acculturation in explaining such differences. PMID:28575113
The Personal and Contextual Contributors to School Belongingness among Primary School Students
Vaz, Sharmila; Falkmer, Marita; Ciccarelli, Marina; Passmore, Anne; Parsons, Richard; Tan, Tele; Falkmer, Torbjorn
2015-01-01
School belongingness has gained currency among educators and school health professionals as an important determinant of adolescent health. The current cross-sectional study presents the 15 most significant personal and contextual factors that collectively explain 66.4% (two-thirds) of the variability in 12-year old students’ perceptions of belongingness in primary school. The study is part of a larger longitudinal study investigating the factors associated with student adjustment in the transition from primary to secondary school. The study found that girls and students with disabilities had higher school belongingness scores than boys, and their typically developing counterparts respectively; and explained 2.5% of the variability in school belongingness. The majority (47.1% out of 66.4%) of the variability in school belongingness was explained by student personal factors, such as social acceptance, physical appearance competence, coping skills, and social affiliation motivation; followed by parental expectations (3% out of 66.4%), and school-based factors (13.9% out of 66.4%) such as, classroom involvement, task-goal structure, autonomy provision, cultural pluralism, and absence of bullying. Each of the identified contributors of primary school belongingness can be shaped through interventions, system changes, or policy reforms. PMID:25876074
Mediating Factors Explaining the Association Between Sexual Minority Status and Dating Violence.
Martin-Storey, Alexa; Fromme, Kim
2017-08-01
Dating violence presents a serious threat for individual health and well-being. A growing body of literature suggests that starting in adolescence, individuals with sexual minority identities (e.g., individuals who identify as gay, lesbian, or bisexual) may be at an increased risk for dating violence compared with heterosexuals. Research has not, however, identified the mechanisms that explain this vulnerability. Using a diverse sample of young adults ( n = 2,474), the current study explored how minority stress theory, revictimization theory, sex of sexual partners, and risky sexual behavior explained differences in dating violence between sexual minority and heterosexual young adults. Initial analyses suggested higher rates of dating violence among individuals who identified as bisexual, and individuals who identified as gay or lesbian when compared with heterosexuals, and further found that these associations failed to differ across gender. When mediating and control variables were included in the analyses, however, the association between both sexual minority identities and higher levels of dating violence became nonsignificant. Of particular interest was the role of discrimination, which mediated the association between bisexual identity and dating violence. Other factors, including sex and number of sexual partners, alcohol use, and childhood maltreatment, were associated with higher rates of dating violence but did not significantly explain vulnerability among sexual minority individuals compared with their heterosexual peers. These findings suggest the importance of minority stress theory in explaining vulnerability to dating violence victimization among bisexuals in particular, and generally support the importance of sexual-minority specific variables in understanding risk for dating violence within this vulnerable population.
Zwaveling-Soonawala, Nitash; van Beijsterveldt, Catharina E M; Mesfum, Ertirea T; Wiedijk, Brenda; Oomen, Petra; Finken, Martijn J J; Boomsma, Dorret I; van Trotsenburg, A S Paul
2015-06-01
The interindividual variability in thyroid hormone function parameters is much larger than the intraindividual variability, suggesting an individual set point for these parameters. There is evidence to suggest that environmental factors are more important than genetic factors in the determination of this individual set point. This study aimed to quantify the effect of genetic factors and (fetal) environment on the early postnatal blood T4 concentration. This was a classical twin study comparing the resemblance of neonatal screening blood T4 concentrations in 1264 mono- and 2566 dizygotic twin pairs retrieved from the population-based Netherlands Twin Register. Maximum-likelihood estimates of variance explained by genetic and environmental influences were obtained by structural equation modeling in data from full-term and preterm twin pairs. In full-term infants, genetic factors explained 40%/31% of the variance in standardized T4 scores in boys/girls, and shared environment, 27%/22%. The remaining variance of 33%/47% was due to environmental factors not shared by twins. For preterm infants, genetic factors explained 34%/0% of the variance in boys/girls, shared environment 31%/57%, and unique environment 35%/43%. In very preterm twins, no significant contribution of genetic factors was observed. Environment explains a large proportion of the resemblance of the postnatal blood T4 concentration in twin pairs. Because we analyzed neonatal screening results, the fetal environment is the most likely candidate for these environmental influences. Genetic influences on the T4 set point diminished with declining gestational age, especially in girls. This may be due to major environmental influences such as immaturity and nonthyroidal illness in very preterm infants.
The genetic and environmental etiology of antisocial behavior from childhood to emerging adulthood.
Tuvblad, Catherine; Narusyte, Jurgita; Grann, Martin; Sarnecki, Jerzy; Lichtenstein, Paul
2011-09-01
Previous research suggests that both genetic and environmental influences are important for antisocial behavior across the life span, even though the prevalence and incidence of antisocial behavior varies considerably across ages. However, little is known of how genetic and environmental effects influence the development of antisocial behavior. A total of 2,600 male and female twins from the population-based Swedish Twin Registry were included in the present study. Antisocial behavior was measured on four occasions, when twins were 8-9, 13-14, 16-17, and 19-20 years old. Longitudinal analyses of the data were conducted using structural equation modeling. The stability of antisocial behavior over time was explained by a common latent persistent antisocial behavior factor. A common genetic influence accounted for 67% of the total variance in this latent factor, the shared environment explained 26%, and the remaining 7% was due to the non-shared environment. Significant age-specific shared environmental factors were found at ages 13-14 years, suggesting that common experiences (e.g., peers) are important for antisocial behavior at this age. Results from this study show that genetic as well as shared environmental influences are important in antisocial behavior that persists from childhood to emerging adulthood.
Occupational conditions and workers' sense of community: variations by gender and race.
Lambert, S J; Hopkins, K
1995-04-01
The literature is reviewed to define a sense of community in the workplace and to identify factors that may foster it. A model is developed and estimated with survey data from a culturally diverse sample of men and women performing lower-level jobs at a medium-sized manufacturing firm. Results of regression analyses are reported that correct for sample selection bias resulting from the lower response rates of minority workers. Findings suggest that well-designed jobs and supportive workplace relationships and policies are important in explaining workers' sense of community, defined as workers' perceptions of mutual commitment between employee and employer. Informal sources of support play a larger role in explaining men's sense of community, while formal sources of support are more important in explaining women's sense of community. Findings further suggest that African American workers, especially women, have a difficult time experiencing a sense of community at work.
Is the notion of central fatigue based on a solid foundation?
Contessa, Paola; Puleo, Alessio; De Luca, Carlo J
2016-02-01
Exercise-induced muscle fatigue has been shown to be the consequence of peripheral factors that impair muscle fiber contractile mechanisms. Central factors arising within the central nervous system have also been hypothesized to induce muscle fatigue, but no direct empirical evidence that is causally associated to reduction of muscle force-generating capability has yet been reported. We developed a simulation model to investigate whether peripheral factors of muscle fatigue are sufficient to explain the muscle force behavior observed during empirical studies of fatiguing voluntary contractions, which is commonly attributed to central factors. Peripheral factors of muscle fatigue were included in the model as a time-dependent decrease in the amplitude of the motor unit force twitches. Our simulation study indicated that the force behavior commonly attributed to central fatigue could be explained solely by peripheral factors during simulated fatiguing submaximal voluntary contractions. It also revealed important flaws regarding the use of the interpolated twitch response from electrical stimulation of the muscle as a means for assessing central fatigue. Our analysis does not directly refute the concept of central fatigue. However, it raises important concerns about the manner in which it is measured and about the interpretation of the commonly accepted causes of central fatigue and questions the very need for the existence of central fatigue. Copyright © 2016 the American Physiological Society.
Gaygısız, Ümmügülsüm; Lajunen, Timo; Gaygısız, Esma
There are considerable cross-national differences in public attitudes towards antibiotics use, use of prescribed antibiotics, and self-medication with antibiotics even within Europe. This study was aimed at investigating the relationships between socio-economic factors, cultural values, national personality characteristics and the antibiotic use in Europe. Data included scores from 27 European countries (14 countries for personality analysis). Correlations between socio-economic variables (Gross National Income per capita, governance quality, life expectancy, mean years of schooling, number of physicians), Hofstede's cultural value dimensions (power distance, individualism, masculinity, uncertainty avoidance, long-term orientation, indulgence), national personality characteristic (extraversion, neuroticism, social desirability) and antibiotic use were calculated and three regression models were constructed. Governance quality (r=-.51), mean years of schooling (r=-.61), power distance (r=.59), masculinity (r=.53), and neuroticism (r=.73) correlated with antibiotic use. The highest amount of variance in antibiotic use was accounted by the cultural values (65%) followed by socio-economic factors (63%) and personality factors (55%). Results show that socio-economic factors, cultural values and national personality characteristics explain cross-national differences in antibiotic use in Europe. In particular, governance quality, uncertainty avoidance, masculinity and neuroticism were important factors explaining antibiotics use. The findings underline the importance of socio-economic and cultural context in health care and in planning public health interventions. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Marteinson, Sarah C; Marcogliese, David J; Verreault, Jonathan
2017-10-01
Daily energy expenditure (DEE) in animals is influenced by many factors although the impact of stressors remains largely unknown. The objective of this study was to determine how multiple physiological stressors (parasite infection and contaminant exposure) and natural challenges (energy-demanding activities and weather conditions) may affect DEE in nesting ring-billed gulls (Larus delawarensis) exposed to high concentrations of persistent organic contaminants (POPs). Physical activity, temperature, gastrointestinal parasitic worm abundance, relative spleen mass, plasma thyroid hormone levels and liver concentrations of POPs were determined; field metabolic rate (FMR) was used as a measure of DEE. For females, FMR was best explained by the percent of time spent in nest-site attendance and exposure to temperatures below their lower critical limit (65% of variation); 32% was also explained by relative spleen mass. In males, FMR was best explained by the number of hours spent in nest site attendance and either relative spleen mass or liver concentrations of tetra-brominated diphenyl ethers (tetra-BDEs) (55% of variation). Relative spleen mass, as an important factor relating to FMR, was best explained by models with a combination of parasite abundance (Diplostomum for females and Eucoleus for males) in a negative relationship, and liver POP concentrations (p,p'-DDE for females and tetra-BDEs for males) in a positive relationship (34%, 55% of variation for females and males, respectively). This study demonstrates that immune activity may be an important factor affecting energy expenditure in ring-billed gulls, and that contaminants and parasite abundance may have both a direct and/or indirect influence on FMR. Copyright © 2017 Elsevier Inc. All rights reserved.
Kim, Kwan-Suk; Seibert, Jacob T; Edea, Zewde; Graves, Kody L; Kim, Eui-Soo; Keating, Aileen F; Baumgard, Lance H; Ross, Jason W; Rothschild, Max F
2018-06-04
Heat stress is one of the limiting factors negatively affecting pig production, health, and fertility. Characterizing genomic regions responsible for variation in HS tolerance would be useful in identifying important genetic factor(s) regulating physiological responses to HS. In the present study, we performed genome-wide association analyses for respiration rate (RR), rectal temperature (TR), and skin temperature (TS) during HS in 214 crossbred gilts genotyped for 68,549 single nucleotide polymorphisms (SNP) using the Porcine SNP 70K BeadChip. Considering the top 0.1% smoothed phenotypic variances explained by SNP windows, we detected 26, 26, 21, and 14 genes that reside within SNPs explaining the largest proportion of variance (top 25 SNP windows) and associated with change in RR (ΔRR) from thermoneutral (TN) conditions to HS environment, as well as the change in prepubertal TR (ΔTR), change in postpubertal ΔTR, and change in TS (ΔTS), respectively. The region between 28.85 Mb and 29.10 Mb on chromosome 16 explained about 0.05% of the observed variation for ΔRR. The growth hormone receptor (GHR) gene resides in this region and is associated with the HS response. The other important candidate genes associated with ΔRR (PAIP1, NNT, and TEAD4), ΔTR (LIMS2, TTR, and TEAD4), and ΔTS (ERBB4, FKBP1B, NFATC2, and ATP9A) have reported roles in the cellular stress response. The SNP explaining the largest proportion of variance and located within and in the vicinity of genes were related to apoptosis or cellular stress and are potential candidates that underlie the physiological response to HS in pigs.
Cheung, Y B
1998-03-01
In view of the rising divorce rates, the impact of divorce on health has an increasing importance in public health. The differentials in health between the married and the divorced may be explained by 'marital selection' and 'marital protection'. Using longitudinal data from a study of the 1958 British birth cohort, factors that select people into divorce were identified from the areas of socio-economic status, health, and attractiveness, which included physical attractiveness, health-related behaviour and temperament. Evidence for both positive and adverse selection is found. The different sets of selection factors for females and males appear to be in line with gender role expectations. The health differentials between married and divorced men were weak and can be explained away by the selection factors. Having controlled for the selection effects, there were still significant associations between divorce and physical and psychological health in women. Though these unexplained differentials cannot be definitely interpreted as the consequences of marital dissolution, this interpretation remains plausible.
Role of Gut Microbiota in the Aetiology of Obesity: Proposed Mechanisms and Review of the Literature
Gerasimidis, Konstantinos; Edwards, Christine Ann; Shaikh, M. Guftar
2016-01-01
The aetiology of obesity has been attributed to several factors (environmental, dietary, lifestyle, host, and genetic factors); however none of these fully explain the increase in the prevalence of obesity worldwide. Gut microbiota located at the interface of host and environment in the gut are a new area of research being explored to explain the excess accumulation of energy in obese individuals and may be a potential target for therapeutic manipulation to reduce host energy storage. Several mechanisms have been suggested to explain the role of gut microbiota in the aetiology of obesity such as short chain fatty acid production, stimulation of hormones, chronic low-grade inflammation, lipoprotein and bile acid metabolism, and increased endocannabinoid receptor system tone. However, evidence from animal and human studies clearly indicates controversies in determining the cause or effect relationship between the gut microbiota and obesity. Metagenomics based studies indicate that functionality rather than the composition of gut microbiota may be important. Further mechanistic studies controlling for environmental and epigenetic factors are therefore required to help unravel obesity pathogenesis. PMID:27703805
Skalická, Věra; Ringdal, Kristen; Witvliet, Margot I.
2015-01-01
Background Socioeconomic inequalities in mortality can be explained by different groups of risk factors. However, little is known whether repeated measurement of risk factors can provide better explanation of socioeconomic inequalities in health. Our study examines the extent to which relative educational and income inequalities in mortality might be explained by explanatory risk factors (behavioral, psychosocial, biomedical risk factors and employment) measured at two points in time, as compared to one measurement at baseline. Methods and Findings From the Norwegian total county population-based HUNT Study (years 1984–86 and 1995–1997, respectively) 61 513 men and women aged 25–80 (82.5% of all enrolled) were followed-up for mortality in 25 years until 2009, employing a discrete time survival analysis. Socioeconomic inequalities in mortality were observed. As compared to their highest socioeconomic counterparts, the lowest educated men had an OR (odds ratio) of 1.41 (95% CI 1.29–1.55) and for the lowest income quartile OR = 1.59 (1.48–1.571), for women OR = 1.35 (1.17–1.55), and OR = 1.40 (1.28–1.52), respectively. Baseline explanatory variables attenuated the association between education and income with mortality by 54% and 54% in men, respectively, and by 69% and 18% in women. After entering time-varying variables, this attainment increased to 63% and 59% in men, respectively, and to 25% (income) in women, with no improvement in regard to education in women. Change in biomedical factors and employment did not amend the explanation. Conclusions Addition of a second measurement for risk factors provided only a modest improvement in explaining educational and income inequalities in mortality in Norwegian men and women. Accounting for change in behavior provided the largest improvement in explained inequalities in mortality for both men and women, as compared to measurement at baseline. Psychosocial factors explained the largest share of income inequalities in mortality for men, but repeated measurement of these factors contributed only to modest improvement in explanation. Further comparative research on the relative importance of explanatory pathways assessed over time is needed. PMID:25853571
Skalická, Věra; Ringdal, Kristen; Witvliet, Margot I
2015-01-01
Socioeconomic inequalities in mortality can be explained by different groups of risk factors. However, little is known whether repeated measurement of risk factors can provide better explanation of socioeconomic inequalities in health. Our study examines the extent to which relative educational and income inequalities in mortality might be explained by explanatory risk factors (behavioral, psychosocial, biomedical risk factors and employment) measured at two points in time, as compared to one measurement at baseline. From the Norwegian total county population-based HUNT Study (years 1984-86 and 1995-1997, respectively) 61 513 men and women aged 25-80 (82.5% of all enrolled) were followed-up for mortality in 25 years until 2009, employing a discrete time survival analysis. Socioeconomic inequalities in mortality were observed. As compared to their highest socioeconomic counterparts, the lowest educated men had an OR (odds ratio) of 1.41 (95% CI 1.29-1.55) and for the lowest income quartile OR = 1.59 (1.48-1.571), for women OR = 1.35 (1.17-1.55), and OR = 1.40 (1.28-1.52), respectively. Baseline explanatory variables attenuated the association between education and income with mortality by 54% and 54% in men, respectively, and by 69% and 18% in women. After entering time-varying variables, this attainment increased to 63% and 59% in men, respectively, and to 25% (income) in women, with no improvement in regard to education in women. Change in biomedical factors and employment did not amend the explanation. Addition of a second measurement for risk factors provided only a modest improvement in explaining educational and income inequalities in mortality in Norwegian men and women. Accounting for change in behavior provided the largest improvement in explained inequalities in mortality for both men and women, as compared to measurement at baseline. Psychosocial factors explained the largest share of income inequalities in mortality for men, but repeated measurement of these factors contributed only to modest improvement in explanation. Further comparative research on the relative importance of explanatory pathways assessed over time is needed.
Goldstein, R.M.; Carlisle, D.M.; Meador, M.R.; Short, T.M.
2007-01-01
The environmental setting (e.g., climate, topography, geology) and land use affect stream physical characteristics singly and cumulatively. At broad geographic scales, we determined the importance of environmental setting and land use in explaining variation in stream physical characteristics. We hypothesized that as the spatial scale decreased from national to regional, land use would explain more of the variation in stream physical characteristics because environmental settings become more homogeneous. At a national scale, stepwise linear regression indicated that environmental setting was more important in explaining variability in stream physical characteristics. Although statistically discernible, the amount of variation explained by land use was not remarkable due to low partial correlations. At level II ecoregion spatial scales (southeastern USA plains, central USA plains, and a combination of the western Cordillera and the western interior basins and ranges), environmental setting variables were again more important predictors of stream physical characteristics, however, as the spatial scale decreased from national to regional, the portion of variability in stream physical characteristics explained by basin land use increased. Development of stream habitat indicators of land use will depend upon an understanding of relations between stream physical characteristics and environmental factors at multiple spatial scales. Smaller spatial scales will be necessary to reduce the confounding effects of variable environmental settings before the effects of land use can be reliably assessed. ?? Springer Science+Business Media B.V. 2006.
State legislative staff influence in health policy making.
Weissert, C S; Weissert, W G
2000-12-01
State legislative staff may influence health policy by gathering intelligence, setting the agenda, and shaping the legislative proposals. But they may also be stymied in their roles by such institutional constraints as hiring practices and by turnover in committee leadership in the legislature. The intervening variable of trust between legislators and their support staff is also key to understanding influence and helps explain how staff-legislator relationships play an important role in designing state health policy. This study of legislative fiscal and health policy committee staff uses data from interviews with key actors in five states to model the factors important in explaining variation in the influence of committee staff on health policy.
Against Methodocentrism in Educational Research
ERIC Educational Resources Information Center
Weaver, John A.; Snaza, Nathan
2017-01-01
This essay defines and critiques "methodocentrism", the belief that predetermined research methods are the determining factor in the validity and importance of educational research. By examining research in science studies and posthumanism, the authors explain how this methodocentrism disenables research from taking account of problems…
Factor Analysis of the Community Balance and Mobility Scale in Individuals with Knee Osteoarthritis.
Takacs, Judit; Krowchuk, Natasha M; Goldsmith, Charles H; Hunt, Michael A
2017-10-01
The clinical assessment of balance is an important first step in characterizing the risk of falls. The Community Balance and Mobility Scale (CB&M) is a test of balance and mobility that was designed to assess performance on advanced tasks necessary for independence in the community. However, other factors that can affect balancing ability may also be present during performance of the real-world tasks on the CB&M. It is important for clinicians to understand fully what other modifiable factors the CB&M may encompass. The purpose of this study was to evaluate the underlying constructs in the CB&M in individuals with knee osteoarthritis (OA). This was an observational study, with a single testing session. Participants with knee OA aged 50 years and older completed the CB&M, a clinical test of balance and mobility. Confirmatory factor analysis was then used to examine whether the tasks on the CB&M measure distinct factors. Three a priori theory-driven models with three (strength, balance, mobility), four (range of motion added) and six (pain and fear added) constructs were evaluated using multiple fit indices. A total of 131 participants (mean [SD] age 66.3 [8.5] years, BMI 27.3 [5.2] kg m -2 ) participated. A three-factor model in which all tasks loaded on these three factors explained 65% of the variance and yielded the most optimal model, as determined using scree plots, chi-squared values and explained variance. The first factor accounted for 49% of the variance and was interpreted as lower limb muscle strength. The second and third factors were interpreted as mobility and balance, respectively. The CB&M demonstrated the measurement of three distinct factors, interpreted as lower limb strength, balance and mobility, supporting the use of the CB&M with people with knee OA for evaluation of these important factors in falls risk and functional mobility. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
What are the most crucial soil factors for predicting the distribution of alpine plant species?
NASA Astrophysics Data System (ADS)
Buri, A.; Pinto-Figueroa, E.; Yashiro, E.; Guisan, A.
2017-12-01
Nowadays the use of species distribution models (SDM) is common to predict in space and time the distribution of organisms living in the critical zone. The realized environmental niche concept behind the development of SDM imply that many environmental factors must be accounted for simultaneously to predict species distributions. Climatic and topographic factors are often primary included, whereas soil factors are frequently neglected, mainly due to the paucity of soil information available spatially and temporally. Furthermore, among existing studies, most included soil pH only, or few other soil parameters. In this study we aimed at identifying what are the most crucial soil factors for explaining alpine plant distributions and, among those identified, which ones further improve the predictive power of plant SDMs. To test the relative importance of the soil factors, we performed plant SDMs using as predictors 52 measured soil properties of various types such as organic/inorganic compounds, chemical/physical properties, water related variables, mineral composition or grain size distribution. We added them separately to a standard set of topo-climatic predictors (temperature, slope, solar radiation and topographic position). We used ensemble forecasting techniques combining together several predictive algorithms to model the distribution of 116 plant species over 250 sites in the Swiss Alps. We recorded the variable importance for each model and compared the quality of the models including different soil proprieties (one at a time) as predictors to models having only topo-climatic variables as predictors. Results show that 46% of the soil proprieties tested become the second most important variable, after air temperature, to explain spatial distribution of alpine plants species. Moreover, we also assessed that addition of certain soil factors, such as bulk soil water density, could improve over 80% the quality of some plant species models. We confirm that soil pH remains one of the most important soil factor for predicting plant species distributions, closely followed by water, organic and inorganic carbon related properties. Finally, we were able to extract three main categories of important soil properties for plant species distributions: grain size distribution, acidity and water in the soil.
Risse-Buhl, Ute; Anlanger, Christine; Kalla, Katalin; Neu, Thomas R; Noss, Christian; Lorke, Andreas; Weitere, Markus
2017-12-15
Previous laboratory and on-site experiments have highlighted the importance of hydrodynamics in shaping biofilm composition and architecture. In how far responses to hydrodynamics can be found in natural flows under the complex interplay of environmental factors is still unknown. In this study we investigated the effect of near streambed turbulence in terms of turbulent kinetic energy (TKE) on the composition and architecture of biofilms matured in two mountainous streams differing in dissolved nutrient concentrations. Over both streams, TKE significantly explained 7% and 8% of the variability in biofilm composition and architecture, respectively. However, effects were more pronounced in the nutrient richer stream, where TKE significantly explained 12% and 3% of the variability in biofilm composition and architecture, respectively. While at lower nutrient concentrations seasonally varying factors such as stoichiometry of dissolved nutrients (N/P ratio) and light were more important and explained 41% and 6% of the variability in biofilm composition and architecture, respectively. Specific biofilm features such as elongated ripples and streamers, which were observed in response to the uniform and unidirectional flow in experimental settings, were not observed. Microbial biovolume and surface area covered by the biofilm canopy increased with TKE, while biofilm thickness and porosity where not affected or decreased. These findings indicate that under natural flows where near bed flow velocities and turbulence intensities fluctuate with time and space, biofilms became more compact. They spread uniformly on the mineral surface as a film of densely packed coccoid cells appearing like cobblestone pavement. The compact growth of biofilms seemed to be advantageous for resisting hydrodynamic shear forces in order to avoid displacement. Thus, near streambed turbulence can be considered as important factor shaping the composition and architecture of biofilms grown under natural flows. Copyright © 2017 Elsevier Ltd. All rights reserved.
The factors controlling species density in herbaceous plant communities: An assessment
Grace, J.B.
1999-01-01
This paper evaluates both the ideas and empirical evidence pertaining to the control of species density in herbaceous plant communities. While most theoretical discussions of species density have emphasized the importance of habitat productivity and disturbance regimes, many other factors (e.g. species pools, plant litter accumulation, plant morphology) have been proposed to be important. A review of literature presenting observations on the density of species in small plots (in the vicinity of a few square meters or less), as well as experimental studies, suggests several generalizations: (1) Available data are consistent with an underlying unimodal relationship between species density and total community biomass. While variance in species density is often poorly explained by predictor variables, there is strong evidence that high levels of community biomass are antagonistic to high species density. (2) Community biomass is just one of several factors affecting variations in species density. Multivariate analyses typically explain more than twice as much variance in species density as can be explained by community biomass alone. (3) Disturbance has important and sometimes complex effects on species density. In general, the evidence is consistent with the intermediate disturbance hypothesis but exceptions exist and effects can be complex. (4) Gradients in the species pool can have important influences on patterns of species density. Evidence is mounting that a considerable amount of the observed variability in species density within a landscape or region may result from environmental effects on the species pool. (5) Several additional factors deserve greater consideration, including time lags, species composition, plant morphology, plant density and soil microbial effects. Based on the available evidence, a conceptual model of the primary factors controlling species density is presented here. This model suggests that species density is controlled by the effects of disturbance, total community biomass, colonization, the species pool and spatial heterogeneity. The structure of the model leads to two main expectations: (1) while community biomass is important, multivariate approaches will be required to understand patterns of variation in species density, and (2) species density will be more highly correlated with light penetration to the soil surface, than with above-ground biomass, and even less well correlated with plant growth rates (productivity) or habitat fertility. At present, data are insufficient to evaluate the relative importance of the processes controlling species density. Much more work is needed if we are to adequately predict the effects of environmental changes on plant communities and species diversity.
Yokoyama, Yoshie; Jelenkovic, Aline; Hur, Yoon-Mi; Sund, Reijo; Fagnani, Corrado; Stazi, Maria A; Brescianini, Sonia; Ji, Fuling; Ning, Feng; Pang, Zengchang; Knafo-Noam, Ariel; Mankuta, David; Abramson, Lior; Rebato, Esther; Hopper, John L; Cutler, Tessa L; Saudino, Kimberly J; Nelson, Tracy L; Whitfield, Keith E; Corley, Robin P; Huibregtse, Brooke M; Derom, Catherine A; Vlietinck, Robert F; Loos, Ruth J F; Llewellyn, Clare H; Fisher, Abigail; Bjerregaard-Andersen, Morten; Beck-Nielsen, Henning; Sodemann, Morten; Krueger, Robert F; McGue, Matt; Pahlen, Shandell; Bartels, Meike; van Beijsterveldt, Catharina E M; Willemsen, Gonneke; Harris, Jennifer R; Brandt, Ingunn; Nilsen, Thomas S; Craig, Jeffrey M; Saffery, Richard; Dubois, Lise; Boivin, Michel; Brendgen, Mara; Dionne, Ginette; Vitaro, Frank; Haworth, Claire M A; Plomin, Robert; Bayasgalan, Gombojav; Narandalai, Danshiitsoodol; Rasmussen, Finn; Tynelius, Per; Tarnoki, Adam D; Tarnoki, David L; Ooki, Syuichi; Rose, Richard J; Pietiläinen, Kirsi H; Sørensen, Thorkild I A; Boomsma, Dorret I; Kaprio, Jaakko; Silventoinen, Karri
2018-05-19
The genetic architecture of birth size may differ geographically and over time. We examined differences in the genetic and environmental contributions to birthweight, length and ponderal index (PI) across geographical-cultural regions (Europe, North America and Australia, and East Asia) and across birth cohorts, and how gestational age modifies these effects. Data from 26 twin cohorts in 16 countries including 57 613 monozygotic and dizygotic twin pairs were pooled. Genetic and environmental variations of birth size were estimated using genetic structural equation modelling. The variance of birthweight and length was predominantly explained by shared environmental factors, whereas the variance of PI was explained both by shared and unique environmental factors. Genetic variance contributing to birth size was small. Adjusting for gestational age decreased the proportions of shared environmental variance and increased the propositions of unique environmental variance. Genetic variance was similar in the geographical-cultural regions, but shared environmental variance was smaller in East Asia than in Europe and North America and Australia. The total variance and shared environmental variance of birth length and PI were greater from the birth cohort 1990-99 onwards compared with the birth cohorts from 1970-79 to 1980-89. The contribution of genetic factors to birth size is smaller than that of shared environmental factors, which is partly explained by gestational age. Shared environmental variances of birth length and PI were greater in the latest birth cohorts and differed also across geographical-cultural regions. Shared environmental factors are important when explaining differences in the variation of birth size globally and over time.
ERIC Educational Resources Information Center
Roodvoets, David L.
2003-01-01
Presents factors to consider when determining roofing life-cycle costs, explaining that costs do not tell the whole story; discussing components that should go into the decision (cost, maintenance, energy use, and environmental costs); and concluding that important elements in reducing life-cycle costs include energy savings through increased…
Colony collapse disorder (CCD) and bee age impact honey bee pathophysiology
USDA-ARS?s Scientific Manuscript database
Honey bee (Apis mellifera) colonies continue to experience high annual losses that remain poorly explained. Numerous interacting factors have been linked to colony declines. Understanding the pathways linking dysfunction with symptoms is an important step in understanding the mechanisms of disease. ...
ERIC Educational Resources Information Center
Stivers, Richard
2004-01-01
If technology is the single most important factor in explaining the organization of modern societies, it is likewise the key to understanding the modern personality. The technological personality is the psychological counterpart to the technological society.Technology indirectly destroys the basis of a common morality and so leaves human…
Dietary Factors Modulate Helicobacter-Associated Gastric Cancer in Rodent Models
Fox, James G.; Wang, Timothy C.
2014-01-01
Since its discovery in 1982, the global importance of H. pylori-induced disease, particularly in developing countries, remains high. The use of rodent models particularly mice, and the unanticipated usefulness of the gerbil to study H. pylori pathogenesis have been used extensively to study the interactions of the host, the pathogen and the environmental conditions influencing the outcome of persistent H. pylori infection. Dietary factors in humans are increasingly recognized as being important factors in modulating progression and severity of H. pylori-induced gastric cancer. Studies using rodent models to verify and help explain mechanisms whereby various dietary ingredients impact disease outcome should continue to be extremely productive. PMID:24301796
Lansaat, Liset; van der Noort, Vincent; Bernard, Simone E; Eerenstein, Simone E J; Plaat, Boudewijn E C; Langeveld, Ton A P M; Lacko, Martin; Hilgers, Frans J M; de Bree, Remco; Takes, Robert P; van den Brekel, Michiel W M
2018-03-01
Incidences of pharyngocutaneous fistulization (PCF) after total laryngectomy (TL) reported in the literature vary widely, ranging from 2.6 to 65.5%. Comparison between different centers might identify risk factors, but also might enable improvements in quality of care. To enable this on a national level, an audit in the 8 principle Dutch Head and Neck Centers (DHNC) was initiated. A retrospective chart review of all 324 patients undergoing laryngectomy in a 2-year (2012 and 2013) period was performed. Overall PCF%, PCF% per center and factors predictive for PCF were identified. Furthermore, a prognostic model predicting the PCF% per center was developed. To provide additional data, a survey among the head and neck surgeons of the participating centers was carried out. Overall PCF% was 25.9. The multivariable prediction model revealed that previous treatment with (chemo)radiotherapy in combination with a long interval between primary treatment and TL, previous tracheotomy, near total pharyngectomy, neck dissection, and BMI < 18 were the best predictors for PCF. Early oral intake did not influence PCF rate. PCF% varied quite widely between centers, but for a large extend this could be explained with the prediction model. PCF performance rate (difference between the PCF% and the predicted PCF%) per DHNC, though, shows that not all differences are explained by factors established in the prediction model. However, these factors explain enough of the differences that, compensating for these factors, hospital is no longer independently predictive for PCF. This nationwide audit has provided valid comparative PCF data confirming the known risk factors from the literature which are important for counseling on PCF risks. Data show that variations in PCF% in the DHNCs (in part) are explainable by the variations in these predictive factors. Since elective neck dissection is a major risk factor for PCF, it only should be performed on well funded indication.
Meñaca, Arantza; Evans, Natalie; Andrew, Erin V W; Toscani, Franco; Finetti, Silvia; Gómez-Batiste, Xavier; Higginson, Irene J; Harding, Richard; Pool, Robert; Gysels, Marjolein
2012-06-01
Evidence from a range of sources demonstrates that end-of-life (EoL) care practices and preferences vary across countries; culture is consistently one of the main explanations given for this. In order to understand how cultural factors are used to explain similarities and differences in EoL care between Spain, Italy and Portugal, database and hand searches were performed and cross-cutting core themes identified. Similarities included higher proportions of people who wished to die at home than actually died at home, a persistent trend for partial disclosure in Italy and Spain, low use of advance directives, and low incidence of all medical EoL decisions (with the exception of terminal sedation) compared to northern European countries. The role of religion and the importance of family ties were the two main cultural factors used to explain the similarities. Further research is needed in order to interpret the important differences that were also found. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Differential heritability of adult and juvenile antisocial traits.
Lyons, M J; True, W R; Eisen, S A; Goldberg, J; Meyer, J M; Faraone, S V; Eaves, L J; Tsuang, M T
1995-11-01
Studies of adult antisocial behavior or criminality usually find genetic factors to be more important than the family environment, whereas studies of delinquency find the family environment to be more important. We compared DSM-III-R antisocial personality disorder symptoms before vs after the age of 15 years within a sample of twins, rather than comparing across studies. We administered the Diagnostic Interview Schedule Version III-revised by telephone to 3226 pairs of male twins from the Vietnam Era Twin Registry. Biometrical modeling was applied to each symptom of antisocial personality disorder and summary measures of juvenile and adult symptoms. Five juvenile symptoms were significantly heritable, and five were significantly influenced by the shared environment. Eight adult symptoms were significantly heritable, and one was significantly influenced by the shared environment. The shared environment explained about six times more variance in juvenile anti-social traits than in adult traits. Shared environmental influences on adult antisocial traits overlapped entirely with those on juvenile traits. Additive genetic factors explained about six times more variance in adult vs juvenile traits. The juvenile genetic determinants overlapped completely with genetic influences on adult traits. The unique environment (plus measurement error) explained the largest proportion of variance in both juvenile and adult antisocial traits. Characteristics of the shared or family environment that promote antisocial behavior during childhood and early adolescence also promote later antisocial behavior, but to a much lesser extent. Genetic causal factors are much more prominent for adult than for juvenile antisocial traits.
Wheelock, Ana; Miraldo, Marisa; Thomson, Angus; Vincent, Charles; Sevdalis, Nick
2017-07-12
Despite continuous efforts to improve influenza vaccination coverage, uptake among high-risk groups remains suboptimal. We aimed to identify policy amenable factors associated with vaccination and to measure their importance in order to assist in the monitoring of vaccination sentiment and the design of communication strategies and interventions to improve vaccination rates. The USA, the UK and France. A total of 2412 participants were surveyed across the three countries. Self-reported influenza vaccination. Between March and April 2014, a stratified random sampling strategy was employed with the aim of obtaining nationally representative samples in the USA, the UK and France through online databases and random-digit dialling. Participants were asked about vaccination practices, perceptions and feelings. Multivariable logistic regression was used to identify factors associated with past influenza vaccination. The models were able to explain 64%-80% of the variance in vaccination behaviour. Overall, sociopsychological variables, which are inherently amenable to policy, were better at explaining past vaccination behaviour than demographic, socioeconomic and health variables. Explanatory variables included social influence (physician), influenza and vaccine risk perceptions and traumatic childhood experiences. Our results indicate that evidence-based sociopsychological items should be considered for inclusion into national immunisation surveys to gauge the public's views, identify emerging concerns and thus proactively and opportunely address potential barriers and harness vaccination drivers. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Epigenetics and environmental exposures.
Stein, Richard A
2012-01-01
It is becoming increasingly apparent that genetic factors are inadequate to fully explain many processes that shape development and disease. For example, monozygotic twin pairs, despite sharing identical DNA sequences, are often discordant for many traits and diseases, indicating that the same genotype can give rise to distinct phenotypes. This points towards the involvement of additional factors that cannot be explained solely by the sequence of the genome. Epigenetic modifications, defined as heritable changes that do not alter the nucleotide sequence, emerge as key factors that regulate chromatin structure and gene expression and, together with genetic factors, provide the mechanistic basis to understand the biological effects of various classes of environmental exposures. Epigenetic mechanisms explain the ability of certain chemical compounds to initiate biological perturbations that can lead to malignancy, despite being weak mutagens or lacking mutagenic activity altogether-a view that challenges old beliefs and opens new avenues in public health. The field of epigenetics also explains the causal link between certain infectious diseases and cancer, a relationship that was first observed over a century ago and was initially discounted, then fell into oblivion and more recently re-emerged as an important concept in biology. A key feature that distinguishes epigenetic modifications from genetic changes is their reversible nature. This provides exciting prophylactic and therapeutic perspectives, some of which already materialised with the approval of the first drugs that modulate the epigenetic machinery, reinforcing the idea that our genes are not our destiny.
Determinants of access to health care for depression in 49 countries: A multilevel analysis.
Araya, Ricardo; Zitko, Pedro; Markkula, Niina; Rai, Dheeraj; Jones, Kelvyn
2018-07-01
The relative importance of individual and country-level factors influencing access to diagnosis and treatment for depression across the world is fairly unknown. We analysed cross-national data from the WHO World Health Surveys. Depression diagnosis and access to health care were ascertained using a structured interview. Logistic Bayesian Multilevel analyses were performed to establish individual and country level factors associated with: (1) receiving a diagnosis and (2) accessing treatment for depression if a diagnosis was ascertained. The sample included 7870 individuals from 49 countries who met ICD-10 criteria for depressive episode in the past 12 months. A third (32%) of these individuals had ever been diagnosed with depression in their lifetime. Among those diagnosed with depression, 66% reported to have ever received treatment for depression. Although individual factors were more important determinants of access to treatment for depression, country-level factors explained 27.6% of the variance in access to diagnosis and 24.1% in access to treatment. Access to treatment for depression improved with increasing country income. Female gender, better education, the presence of physical co-morbidity, more material assets, and living in urban areas were individual level determinants of better access. Data on other contextual factors was not available. Unmet need was likely underestimated, since only lifetime treatment data was available. This study highlights major inequalities in access to a diagnosis and treatment of depression. Unlike the prevalence of depression, where contextual factors have shown to have less importance, a significant proportion of the variance in access to depression care was explained by country-level income. Copyright © 2018 Elsevier B.V. All rights reserved.
Guyana dolphins (Sotalia guianensis) from Costa Rica emit whistles that vary with surface behaviors.
May-Collado, Laura J
2013-10-01
Guyana dolphins show remarkable intraspecific whistle variation. This variation has been largely explained in terms of distance among populations; however, other factors such as behavior may also be important. A broadband recording system recorded the whistles of Guyana dolphins under three behavioral states. A discriminant analysis found that during social and travel events, dolphins emit whistles with high delta and minimum frequency, respectively. Whistle duration was also important in discriminating behaviors. This study indicates that behavior is an important factor contributing to whistle variation of Guyana dolphins. Understanding how dolphin whistles vary with behavioral context will advance our understanding of dolphin communication and enable appropriate comparative studies.
Dollard, Maureen F; Neser, Daniel Y
2013-09-01
Work stress is recognized globally as a social determinant of worker health. Therefore we explored whether work stress related factors explained national differences in health and productivity (gross domestic product (GDP)). We proposed a national worker health productivity model whereby macro market power factors (i.e. union density), influence national worker health and GDP via work psychosocial factors and income inequality. We combined five different data sets canvasing 31 wealthy European countries. Aggregated worker self-reported health accounted for 13 per cent of the variance in national life expectancy and in national gross domestic product (GDP). The most important factors explaining worker self-reported health and GDP between nations were two levels of labor protection, macro-level (union density), and organizational-level (psychosocial safety climate, PSC, i.e. the extent of management concern for worker psychological health). The majority of countries with the highest levels of union density and PSC (i.e., workplace protections) were Social Democratic in nature (i.e., Sweden, Finland, Denmark, Norway). Results support a type of society explanation that social and economic factors (e.g., welfare regimes, work related policies) in concert with political power agents at a national level explain in part national differences in workplace protection (PSC) that are important for worker health and productivity. Attention should be given across all countries, to national policies to improve worker health, by bolstering national and local democratic processes and representation to address and implement policies for psychosocial risk factors for work stress, bullying and violence. Results suggest worker health is good for the economy, and should be considered in national health and productivity accounting. Eroding unionism may not be good for worker health or the economy either. Copyright © 2013 Elsevier Ltd. All rights reserved.
Racial and ethnic disparities in antidepressant drug use.
Chen, Jie; Rizzo, John A
2008-12-01
Little is known about racial and ethnic disparities in health care utilization, expenditures and drug choice in the antidepressant market. This study investigates factors associated with the racial and ethnic disparities in antidepressant drug use. We seek to determine the extent to which disparities reflect differences in observable population characteristics versus heterogeneity across racial and ethnic groups. Among the population characteristics, we are interested in identifying which factors are most important in accounting for racial and ethnic disparities in antidepressant drug use. Using Medical Expenditure Panel Survey (MEPS) data from 1996-2003, we have an available sample of 10,416 Caucasian, 1,089 African American and 1,539 Hispanic antidepressant drug users aged 18 to 64 years. We estimate individual out-of-pocket payments, total prescription drug expenditures, drug utilization, the probability of taking generic versus brand name antidepressants, and the share of drugs that are older types of antidepressants (e.g., TCAs and MAOIs) for these individuals during a calendar year. Blinder-Oaxaca decomposition techniques are employed to determine the extent to which disparities reflect differences in observable population characteristics versus unobserved heterogeneity across racial and ethnic groups. Caucasians have the highest antidepressant drug expenditures and utilization. African-Americans have the lowest drug expenditures and Hispanics have the lowest drug utilization. Relative to Caucasians and Hispanics, African-Americans are more likely to purchase generics and use a higher share of older drugs (e.g., TCAs and MAOIs). Differences in observable characteristics explain most of the racial/ethnic differences in these outcomes, with the exception of drug utilization. Differences in health insurance and education levels are particularly important factors in explaining disparities. In contrast, differences in drug utilization largely reflect unobserved heterogeneity across these population groups. Substantive racial and ethnic disparities exist in all dimensions of antidepressant drug use examined. Observable population characteristics account for most of the differences in the expenditures, with health insurance and education key factors driving differences in spending. Observable characteristics are also important in explaining racial and ethnic disparities in the probability of purchasing generics and new vs old antidepressant drugs used. Differences in total utilization are not well-explained by observable characteristics, and may reflect unobserved heterogeneity such as unobserved physician-patient relationships, mistrust, and cultural factors. Reducing differences in observable characteristics such as health insurance and education will mitigate racial and ethnic disparities in expenditures on antidepressant drug use and in the types of antidepressant used (e.g., generics vs. brands; new vs old). But these factors will have less influence in reducing racial and ethnic disparities in overall antidepressant drug utilization. To limit differences in overall antidepressant drug use, policymakers must take into account cultural factors and other sources of heterogeneity.
Adapting to Change: What Motivates Manitoban Schools to Learn
ERIC Educational Resources Information Center
Lam, Y. L. Jack
2004-01-01
This study assesses the relative importance of environmental, intraorganizational, and contextual factors that explain the process and outcomes of organizational learning in six Manitoba schools. Based on the data provided by 265 teaching staff and their principals, the present findings verified that transformational leadership, supportive school…
Influence of childhood adversity on health among male UK military personnel.
Iversen, Amy C; Fear, Nicola T; Simonoff, Emily; Hull, Lisa; Horn, Oded; Greenberg, Neil; Hotopf, Matthew; Rona, Roberto; Wessely, Simon
2007-12-01
Exposure to childhood adversity may explain why only a minority of combatants exposed to trauma develop psychological problems. To examine the association between self-reported childhood vulnerability and later health outcomes in a large randomly selected male military cohort. Data are derived from the first stage of a cohort study comparing Iraq veterans and non-deployed UK military personnel. We describe data collected by questionnaire from males in the regular UK armed forces (n=7937). Pre-enlistment vulnerability is associated with being single, of lower rank, having low educational attainment and serving in the Army. Pre-enlistment vulnerability is associated with a variety of negative health outcomes. Two main factors emerge as important predictors of ill health: a 'family relationships' factor reflecting the home environment and an 'externalising behaviour' factor reflecting behavioural disturbance. Pre-enlistment vulnerability is an important individual risk factor for ill health in military men. Awareness of such factors is important in understanding post-combat psychiatric disorder.
Heritability of the Number of Teeth in Middle-Aged and Older Danish Twins.
Kurushima, Y; Silventoinen, K; Dokkedal, U; Skytthe, A; Mucci, L A; Christensen, K; Hjelmborg, J V B
2017-12-01
Tooth loss is a common health concern in older adults. We aimed to estimate the relative contributions of genetic and environmental factors to the variation in the number of teeth in middle-aged and older populations using a population-based cohort of Danish twins. The study included 5,269 Danish middle-aged or older twins who provided data on the number of teeth at baseline by structured interviews. The data were analyzed using univariate liability threshold modeling, stratified by sex and age, to estimate familial risk of tooth loss as well as estimates of heritability. In the whole cohorts, 23% of participants were edentate and 53% had retained 20 or more teeth. A statistical model including additive genetic factors and environmental factors partly shared by co-twins and partly unique to each individual twin gave the best statistical fit for the number of teeth in both age categories as well as in men and women. Overall, additive genetic factors explained 36% (95% confidence interval [CI]: 23% to 49%), common environmental factors 20% (95% CI: 9% to 31%), and unique environmental factors 44% (95% CI: 40% to 48%) of the total variation of the number of teeth. This study indicates that a substantial part of the variation in tooth loss is explained by genetic as well as environmental factors shared by co-twins. Our results implied that family background importantly affects tooth loss in both the middle-aged and the older populations. Family history is thus an important factor to take into account in dental health care.
Boosted Regression Tree Models to Explain Watershed ...
Boosted regression tree (BRT) models were developed to quantify the nonlinear relationships between landscape variables and nutrient concentrations in a mesoscale mixed land cover watershed during base-flow conditions. Factors that affect instream biological components, based on the Index of Biotic Integrity (IBI), were also analyzed. Seasonal BRT models at two spatial scales (watershed and riparian buffered area [RBA]) for nitrite-nitrate (NO2-NO3), total Kjeldahl nitrogen, and total phosphorus (TP) and annual models for the IBI score were developed. Two primary factors — location within the watershed (i.e., geographic position, stream order, and distance to a downstream confluence) and percentage of urban land cover (both scales) — emerged as important predictor variables. Latitude and longitude interacted with other factors to explain the variability in summer NO2-NO3 concentrations and IBI scores. BRT results also suggested that location might be associated with indicators of sources (e.g., land cover), runoff potential (e.g., soil and topographic factors), and processes not easily represented by spatial data indicators. Runoff indicators (e.g., Hydrological Soil Group D and Topographic Wetness Indices) explained a substantial portion of the variability in nutrient concentrations as did point sources for TP in the summer months. The results from our BRT approach can help prioritize areas for nutrient management in mixed-use and heavily impacted watershed
From deficit to surplus: An econometric analysis of US trade balance in forest products
Daowei Zhang; Ying Lin; Jeffrey P. Prestemon
2017-01-01
Although the US trade deficit has persisted since 1975, the country changed in 2009 from a net importer to a net exporter of forest products, emerging as the world's largest exporter of forest products. Drawing on recent data, we model the real dollar value of US exports, imports, and the trade balance in forest products to identify factors likely to explain this...
Veenstra, Gerry
2012-10-12
Canadian research on racial health inequalities that foregrounds socially constructed racial identities and social factors which can explain consequent racial health inequalities is rare. This paper adopts a social typology of salient racial identities in contemporary Canada, empirically documents consequent racial inequalities in hypertension in an original survey dataset from Toronto and Vancouver, Canada, and then attempts to explain the inequalities in hypertension with information on socioeconomic status, perceived experiences with institutionalized and interpersonal discrimination, and psychosocial stress. Telephone interviews were conducted in 2009 with 706 randomly selected adults living in the City of Toronto and 838 randomly selected adults living in the Vancouver Census Metropolitan Area. Bivariate analyses and logistic regression modeling were used to examine relationships between racial identity, hypertension, socio-demographic factors, socioeconomic status, perceived discrimination and psychosocial stress. The Black Canadians in the sample were the most likely to report major and routine discriminatory experiences and were the least educated and the poorest. Black respondents were significantly more likely than Asian, South Asian and White respondents to report hypertension controlling for age, immigrant status and city of residence. Of the explanatory factors examined in this study, only educational attainment explained some of the relative risk of hypertension for Black respondents. Most of the risk remained unexplained in the models. Consistent with previous Canadian research, socioeconomic status explained a small portion of the relatively high risk of hypertension documented for the Black respondents. Perceived experiences of discrimination both major and routine and self-reported psychosocial stress did not explain these racial inequalities in hypertension. Conducting subgroup analyses by gender, discerning between real and perceived experiences of discrimination and considering potentially moderating factors such as coping strategy and internalization of racial stereotypes are important issues to address in future Canadian racial inequalities research of this kind.
Lin, Guojun; Stralberg, Diana; Gong, Guiquan; Huang, Zhongliang; Ye, Wanhui; Wu, Linfang
2013-01-01
Quantifying the relative contributions of environmental conditions and spatial factors to species distribution can help improve our understanding of the processes that drive diversity patterns. In this study, based on tree inventory, topography and soil data from a 20-ha stem-mapped permanent forest plot in Guangdong Province, China, we evaluated the influence of different ecological processes at different spatial scales using canonical redundancy analysis (RDA) at the community level and multiple linear regression at the species level. At the community level, the proportion of explained variation in species distribution increased with grid-cell sizes, primarily due to a monotonic increase in the explanatory power of environmental variables. At the species level, neither environmental nor spatial factors were important determinants of overstory species' distributions at small cell sizes. However, purely spatial variables explained most of the variation in the distributions of understory species at fine and intermediate cell sizes. Midstory species showed patterns that were intermediate between those of overstory and understory species. At the 20-m cell size, the influence of spatial factors was stronger for more dispersal-limited species, suggesting that much of the spatial structuring in this community can be explained by dispersal limitation. Comparing environmental factors, soil variables had higher explanatory power than did topography for species distribution. However, both topographic and edaphic variables were highly spatial structured. Our results suggested that dispersal limitation has an important influence on fine-intermediate scale (from several to tens of meters) species distribution, while environmental variability facilitates species distribution at intermediate (from ten to tens of meters) and broad (from tens to hundreds of meters) scales.
Santos Tavares Silva, I; Sunnerhagen, K S; Willén, C; Ottenvall Hammar, I
2016-11-18
Fatigue is reported as one of the most disabling symptoms and is common among persons living with late effects of polio. Although fatigue has been studied in the context of people living with late effects of polio, there is a lack of knowledge concerning the association of fatigue and variables of importance for participation in daily life. Therefore, the aim of this study was to explore possible factors associated with fatigue among persons with late effects of polio in Sweden. This retrospective registry study consisted of 89 persons with late effects of polio living in Sweden. Fatigue was measured with the Multidimensional Fatigue Inventory (MFI-20) scale, Swedish version. Pearson's correlation coefficient was used to analyse the correlation between the factors and fatigue, and a multiple linear regression was carried out to explore factors for fatigue. Fatigue statistically significantly correlated with age (r = 0.234, p < 0.05) and the use of mobility assistive devices (r = 0.255, p < 0.05). The multiple linear regression model showed that the factors age (β = 0.304, p < 0.019) and mobility assistive devices (β = 0.262, p < 0.017) were associated with fatigue among persons living with late effects of polio, and the model partly explained 14% of the variation of fatigue. Fatigue could partly be explained by the extent of using mobility assistive devices and age. Healthcare professionals should provide and demonstrate the importance of assistive devices to ensure management of fatigue in persons living with late effects of polio.
Luo, Zhenhua; Tang, Songhua; Li, Chunwang; Fang, Hongxia; Hu, Huijian; Yang, Ji; Ding, Jingjing; Jiang, Zhigang
2012-01-01
Explaining species richness patterns is a central issue in biogeography and macroecology. Several hypotheses have been proposed to explain the mechanisms driving biodiversity patterns, but the causes of species richness gradients remain unclear. In this study, we aimed to explain the impacts of energy, environmental stability, and habitat heterogeneity factors on variation of vertebrate species richness (VSR), based on the VSR pattern in China, so as to test the energy hypothesis, the environmental stability hypothesis, and the habitat heterogeneity hypothesis. A dataset was compiled containing the distributions of 2,665 vertebrate species and eleven ecogeographic predictive variables in China. We grouped these variables into categories of energy, environmental stability, and habitat heterogeneity and transformed the data into 100 × 100 km quadrat systems. To test the three hypotheses, AIC-based model selection was carried out between VSR and the variables in each group and correlation analyses were conducted. There was a decreasing VSR gradient from the southeast to the northwest of China. Our results showed that energy explained 67.6% of the VSR variation, with the annual mean temperature as the main factor, which was followed by annual precipitation and NDVI. Environmental stability factors explained 69.1% of the VSR variation and both temperature annual range and precipitation seasonality had important contributions. By contrast, habitat heterogeneity variables explained only 26.3% of the VSR variation. Significantly positive correlations were detected among VSR, annual mean temperature, annual precipitation, and NDVI, whereas the relationship of VSR and temperature annual range was strongly negative. In addition, other variables showed moderate or ambiguous relations to VSR. The energy hypothesis and the environmental stability hypothesis were supported, whereas little support was found for the habitat heterogeneity hypothesis.
Luo, Zhenhua; Tang, Songhua; Li, Chunwang; Fang, Hongxia; Hu, Huijian; Yang, Ji; Ding, Jingjing; Jiang, Zhigang
2012-01-01
Background Explaining species richness patterns is a central issue in biogeography and macroecology. Several hypotheses have been proposed to explain the mechanisms driving biodiversity patterns, but the causes of species richness gradients remain unclear. In this study, we aimed to explain the impacts of energy, environmental stability, and habitat heterogeneity factors on variation of vertebrate species richness (VSR), based on the VSR pattern in China, so as to test the energy hypothesis, the environmental stability hypothesis, and the habitat heterogeneity hypothesis. Methodology/Principal Findings A dataset was compiled containing the distributions of 2,665 vertebrate species and eleven ecogeographic predictive variables in China. We grouped these variables into categories of energy, environmental stability, and habitat heterogeneity and transformed the data into 100×100 km quadrat systems. To test the three hypotheses, AIC-based model selection was carried out between VSR and the variables in each group and correlation analyses were conducted. There was a decreasing VSR gradient from the southeast to the northwest of China. Our results showed that energy explained 67.6% of the VSR variation, with the annual mean temperature as the main factor, which was followed by annual precipitation and NDVI. Environmental stability factors explained 69.1% of the VSR variation and both temperature annual range and precipitation seasonality had important contributions. By contrast, habitat heterogeneity variables explained only 26.3% of the VSR variation. Significantly positive correlations were detected among VSR, annual mean temperature, annual precipitation, and NDVI, whereas the relationship of VSR and temperature annual range was strongly negative. In addition, other variables showed moderate or ambiguous relations to VSR. Conclusions/Significance The energy hypothesis and the environmental stability hypothesis were supported, whereas little support was found for the habitat heterogeneity hypothesis. PMID:22530038
Sources of variation in waterfowl survival rates
Krementz, D.G.; Barker, R.J.; Nichols, J.D.
1997-01-01
Because of the need to manage hunted populations of waterfowl (Anatidae), biologists have studied many demographic traits of waterfowl by analyzing band recoveries. These analyses have produced the most extensive and best estimates of survival available for any group of birds. Using these data, we examined several factors that might explain variation among annual survival rates to explore large-scale patterns that might be useful in understanding waterfowl population dynamics. We found that geography, body mass, and tribe (i.e. phylogeny) were important in explaining variation in average waterfowl survival rates.
Historical factors shaped species diversity and composition of Salix in eastern Asia.
Wang, Qinggang; Su, Xiangyan; Shrestha, Nawal; Liu, Yunpeng; Wang, Siyang; Xu, Xiaoting; Wang, Zhiheng
2017-02-08
Ambient energy, niche conservatism, historical climate stability and habitat heterogeneity hypothesis have been proposed to explain the broad-scale species diversity patterns and species compositions, while their relative importance have been controversial. Here, we assessed the relative contributions of contemporary climate, historical climate changes and habitat heterogeneity in shaping Salix species diversity and species composition in whole eastern Asia as well as mountains and lowlands using linear regressions and distance-based redundancy analyses, respectively. Salix diversity was negatively related with mean annual temperature. Habitat heterogeneity was more important than contemporary climate in shaping Salix diversity patterns, and their relative contributions were different in mountains and lowlands. In contrast, the species composition was strongly influenced by contemporary climate and historical climate change than habitat heterogeneity, and their relative contributions were nearly the same both in mountains and lowlands. Our findings supported niche conservatism and habitat heterogeneity hypotheses, but did not support ambient energy and historical climate stability hypotheses. The diversity pattern and species composition of Salix could not be well-explained by any single hypothesis tested, suggesting that other factors such as disturbance history and diversification rate may be also important in shaping the diversity pattern and composition of Salix species.
Historical factors shaped species diversity and composition of Salix in eastern Asia
Wang, Qinggang; Su, Xiangyan; Shrestha, Nawal; Liu, Yunpeng; Wang, Siyang; Xu, Xiaoting; Wang, Zhiheng
2017-01-01
Ambient energy, niche conservatism, historical climate stability and habitat heterogeneity hypothesis have been proposed to explain the broad-scale species diversity patterns and species compositions, while their relative importance have been controversial. Here, we assessed the relative contributions of contemporary climate, historical climate changes and habitat heterogeneity in shaping Salix species diversity and species composition in whole eastern Asia as well as mountains and lowlands using linear regressions and distance-based redundancy analyses, respectively. Salix diversity was negatively related with mean annual temperature. Habitat heterogeneity was more important than contemporary climate in shaping Salix diversity patterns, and their relative contributions were different in mountains and lowlands. In contrast, the species composition was strongly influenced by contemporary climate and historical climate change than habitat heterogeneity, and their relative contributions were nearly the same both in mountains and lowlands. Our findings supported niche conservatism and habitat heterogeneity hypotheses, but did not support ambient energy and historical climate stability hypotheses. The diversity pattern and species composition of Salix could not be well-explained by any single hypothesis tested, suggesting that other factors such as disturbance history and diversification rate may be also important in shaping the diversity pattern and composition of Salix species. PMID:28176816
47 CFR 101.1011 - Construction requirements and criteria for renewal expectancy.
Code of Federal Regulations, 2010 CFR
2010-10-01
... applicant involved in a comparative renewal proceeding shall receive a preference, commonly referred to as a renewal expectancy, that is the most important comparative factor to be considered in the proceeding as... comparative renewal proceeding must submit a showing explaining why it should receive a renewal expectancy. At...
47 CFR 101.1011 - Construction requirements and criteria for renewal expectancy.
Code of Federal Regulations, 2014 CFR
2014-10-01
... applicant involved in a comparative renewal proceeding shall receive a preference, commonly referred to as a renewal expectancy, that is the most important comparative factor to be considered in the proceeding as... comparative renewal proceeding must submit a showing explaining why it should receive a renewal expectancy. At...
47 CFR 101.1011 - Construction requirements and criteria for renewal expectancy.
Code of Federal Regulations, 2012 CFR
2012-10-01
... applicant involved in a comparative renewal proceeding shall receive a preference, commonly referred to as a renewal expectancy, that is the most important comparative factor to be considered in the proceeding as... comparative renewal proceeding must submit a showing explaining why it should receive a renewal expectancy. At...
47 CFR 101.1011 - Construction requirements and criteria for renewal expectancy.
Code of Federal Regulations, 2011 CFR
2011-10-01
... applicant involved in a comparative renewal proceeding shall receive a preference, commonly referred to as a renewal expectancy, that is the most important comparative factor to be considered in the proceeding as... comparative renewal proceeding must submit a showing explaining why it should receive a renewal expectancy. At...
47 CFR 101.1011 - Construction requirements and criteria for renewal expectancy.
Code of Federal Regulations, 2013 CFR
2013-10-01
... applicant involved in a comparative renewal proceeding shall receive a preference, commonly referred to as a renewal expectancy, that is the most important comparative factor to be considered in the proceeding as... comparative renewal proceeding must submit a showing explaining why it should receive a renewal expectancy. At...
Seasonal Variation in Epidemiology
ERIC Educational Resources Information Center
Marrero, Osvaldo
2013-01-01
Seasonality analyses are important in medical research. If the incidence of a disease shows a seasonal pattern, then an environmental factor must be considered in its etiology. We discuss a method for the simultaneous analysis of seasonal variation in multiple groups. The nuts and bolts are explained using simple trigonometry, an elementary…
Contemporary Economic Debate in Britain: A View from Afar.
ERIC Educational Resources Information Center
Edwards, Ron; Millnow, Alex
1992-01-01
Seeks to explain economists' differences of opinion, through the example of contemporary British economic debate. Observes that part of the explanation lies in the complexity of economic issues. Argues that the more important factor lies in economists' ideological differences. Contrasts the views of the libertarian and market interventionist…
An Intervention to Retrain Attributions Using CBT: A Pilot Study
ERIC Educational Resources Information Center
Bosnjak, Amira; Boyle, Christopher; Chodkiewicz, Alicia R.
2017-01-01
The role of affective and cognitive factors in learning have long been recognised as imperative determinants of the learning process. Maladaptive styles with which we perceive and explain accomplishments and failures in achievement outcomes have an important motivational impact upon approach and avoidance behaviours towards academic tasks.…
Building Databases for Education. ERIC Digest.
ERIC Educational Resources Information Center
Klausmeier, Jane A.
This digest provides a brief explanation of what a database is; explains how a database can be used; identifies important factors that should be considered when choosing database management system software; and provides citations to sources for finding reviews and evaluations of database management software. The digest is concerned primarily with…
Bunnell, David B.; Madenjian, Charles P.; Croley, Thomas E.
2006-01-01
Long-term population trends are generally explained by factors extrinsic (e.g., climate, predation) rather than intrinsic (e.g., genetics, maternal effects) to the population. We sought to understand the long-term population dynamics of an important native Lake Michigan prey fish, the bloaterCoregonus hoyi. Over a 38-year time series, three 10- to 15-year phases occurred (poor, excellent, and then poor recruitment) without high interannual variability within a particular phase. We used dynamic linear models to determine whether extrinsic (winter and spring temperature, alewife predator densities) or intrinsic factors (population egg production, adult condition, adult sex ratio) explained variation in recruitment. Models that included population egg production, sex ratio, winter and spring temperature, and adult bloater condition explained the most variation. Of these variables, sex ratio, which ranged from 47% to 97% female across the time series, consistently had the greatest effect: recruitment declined with female predominance. Including biomass of adult alewife predators in the models did not explain additional variation. Overall our results indicated that bloater recruitment is linked to its sex ratio, but understanding the underlying mechanisms will require additional efforts.
Dellve, Lotta; Karlberg, Catarina; Allebeck, Peter; Herloff, Birgitta; Hagberg, Mats
2006-01-01
To investigate the importance of macro-organizational factors, i.e. organizational sociodemographic and socioeconomic preconditions, of the municipal incidence of long-term sick leave, disability pension, and prevalence of workers with long-term work ability among home care workers. In an ecological study design, data from national databases were combined by record linkage. Descriptive and analytical statistics were used to estimate and interpret macro-organizational factors (economic resources, region, unemployment, employment, occupational rehabilitation, return to work, age structures of inhabitants and home care workers). The incidence of long-term sick leave among female home care workers was twice as high as that of male home care workers, and incidence of disability pension was about four times as high for the women. A great variation in municipal incidence of long-term sick leave, disability pension, and long-term work ability (101-264, 0.6-19.6, and 913-1,279 per 1,000 full-time equivalent workers and year) was also found. The strongest single factor for long-term work ability was a high proportion of part-time or hourly paid employees, which explained 35% of the municipal variation. Macro-organizational factors explained long-term work ability (47-62% explained variance) better than long-term sick leave (33% explained variance). There was a low rehabilitation activity; only 2% received occupational rehabilitation and 5% of those on sick leave longer than 2 weeks returned to work within 30 days. The differences in the municipal proportion of work ability incidence indicate a preventive potential, especially related to employment and return to work after sick leave.
Rising Educational Gradients in Mortality: The Role of Behavioral Risk Factors
Cutler, David M; Meara, Ellen; Richards-Shubik, Seth; Ruhm, Christopher J
2013-01-01
The long-standing inverse relationship between education and mortality strengthened substantially at the end of the 20th century. This paper examines the reasons for this increase. We show that behavioral risk factors are not of primary importance. Smoking declined more for the better educated, but not enough to explain the trend. Obesity rose at similar rates across education groups, and control of blood pressure and cholesterol increased fairly uniformly as well. Rather, our results show that the mortality returns to risk factors, and conditional on risk factors, the return to education, have grown over time. PMID:21925754
Gevers, Dorus Wm; van Assema, Patricia; de Vries, Nanne K; Kremers, Stef Pj
2017-09-01
The high energy intake from energy-dense foods among children in developed countries is undesirable. Improving food parenting practices has the potential to lower snack intakes among children. To inform the development of interventions, we aimed to predict food parenting practice patterns around snacking (i.e. 'high covert control and rewarding', 'low covert control and non-rewarding', 'high involvement and supportive' and 'low involvement and indulgent'). A cross-sectional survey was conducted. To predict the patterns of food parenting practices, multinomial logistic regression analyses were run with 888 parents. Predictors included predisposing factors (i.e. parents' and children's demographics and BMI, parents' personality, general parenting, and parenting practices used by their own parents) and parents' cognitions (i.e. perceived behaviour of other parents, subjective norms, attitudes, self-efficacy and outcome expectations). The Netherlands (October-November 2014). Dutch parents of children aged 4-12 years old. After backward elimination, nineteen factors had a statistically significant contribution to the model (Nagelkerke R 2=0·63). Overall, self-efficacy and outcome expectations were among the strongest explanatory factors. Considering the predisposing factors only, the general parenting factor nurturance most strongly predicted the food parenting clusters. Nurturance particularly distinguished highly involved parents from parents employing a pattern of low involvement. Parental cognitions and nurturance are important factors to explain the use of food parenting practices around snacking. The results suggest that intervention developers should attempt to increase self-efficacy and educate parents about what constitute effective and ineffective parenting practices. Promoting nurturance might be a prerequisite to achieve prolonged change.
Vangen-Lønne, Anne M; Wilsgaard, Tom; Johnsen, Stein Harald; Løchen, Maja-Lisa; Njølstad, Inger; Mathiesen, Ellisiv B
2017-03-01
It is proposed that 20% to 40% of the decline in first-ever stroke incidence is attributed to the improvement of risk factor control. We estimated the impact of modifiable cardiovascular risk factors on the changing incidence of ischemic stroke (IS) between 1995 and 2012, using individual person data from repeated surveys in a general population. The proportion of the IS incidence decline explained by change in each risk factor over time was estimated from 1995 to 2012 by Poisson regression among 26 329 participants who attended the fourth Tromsø survey in 1994 to 1995. Hazard ratios for IS were estimated with Cox proportional hazards regression among 27 936 participants who attended at least 1 of the Tromsø surveys in 1994 to 1995, 2001, or 2007 to 2008. Age- and sex-adjusted means or prevalences of risk factors over time were estimated by generalized estimating equations. There were 1226 first-ever IS during 367 636 person-years of follow-up. Changes in cardiovascular risk factors accounted for 57% of the decrease in IS incidence from 1995 to 2012. The most important contributors were decreasing mean systolic blood pressure and smoking prevalence, accounting for 26% and 17% of the observed decline, respectively. Conversely, increasing diabetes mellitus prevalence contributed negatively to the declining IS incidence. Changes in cardiovascular risk factors explained 57% of the decrease in IS incidence from 1995 to 2012. Reduction in systolic blood pressure and prevalence of smoking were the most important contributors. © 2017 American Heart Association, Inc.
Gestalt factors modulate basic spatial vision.
Sayim, B; Westheimer, G; Herzog, M H
2010-05-01
Human perception of a stimulus varies depending on the context in which the stimulus is presented. Such contextual modulation has often been explained by two basic neural mechanisms: lateral inhibition and spatial pooling. In the present study, we presented observers with a vernier stimulus flanked by single lines; observers' ability to discriminate the offset direction of the vernier stimulus deteriorated in accordance with both explanations. However, when the flanking lines were part of a geometric shape (i.e., a good Gestalt), this deterioration strongly diminished. These findings cannot be explained by lateral inhibition or spatial pooling. It seems that Gestalt factors play an important role in contextual modulation. We propose that contextual modulation can be used as a quantitative measure to investigate the rules governing the grouping of elements into meaningful wholes.
Characterizing the astrophysical S factor for 12C+12C fusion with wave-packet dynamics
NASA Astrophysics Data System (ADS)
Diaz-Torres, Alexis; Wiescher, Michael
2018-05-01
A quantitative study of the astrophysically important subbarrier fusion of 12C+12C is presented. Low-energy collisions are described in the body-fixed reference frame using wave-packet dynamics within a nuclear molecular picture. A collective Hamiltonian drives the time propagation of the wave packet through the collective potential-energy landscape. The fusion imaginary potential for specific dinuclear configurations is crucial for understanding the appearance of resonances in the fusion cross section. The theoretical subbarrier fusion cross sections explain some observed resonant structures in the astrophysical S factor. These cross sections monotonically decline towards stellar energies. The structures in the data that are not explained are possibly due to cluster effects in the nuclear molecule, which need to be included in the present approach.
Eklund, Mona; Ostman, Margareta
2010-07-01
It is increasingly acknowledged that satisfaction with sexual relations forms an important aspect of people's lives, but little is known of factors associated with this phenomenon among people with mental illness. This study aimed to investigate how demographic, social, clinical, and health-related factors were related to satisfaction with sexual relations. Patients with persistent mental illness (N = 103), recruited from an outpatient unit, were assessed regarding the target variables. No clinical variable, and only one demographic factor, namely being a cohabitant, was found to be important to satisfaction with sexual relations. Several social factors, pertaining to how everyday occupations were valued and how the social network was perceived, were shown to be of importance. General quality of life, but not self-rated health or interviewer-assessed psychopathology, was also important for satisfaction with sexual relations. A multivariate analysis showed that the most significant factor for satisfaction with sexual relations was how everyday activities were valued, and being a cohabitant explained some additional variation. Previous research indicates that the mental health care services largely neglect sexual problems among people with mental illness, and the findings may provide additional knowledge that may be used in the support of this target group.
Luzak, Agnes; Fuertes, Elaine; Flexeder, Claudia; Standl, Marie; von Berg, Andrea; Berdel, Dietrich; Koletzko, Sibylle; Heinrich, Joachim; Nowak, Dennis; Schulz, Holger
2017-07-12
Various factors may affect lung function at different stages in life. Since investigations that simultaneously consider several factors are rare, we examined the relative importance of early life, current environmental/lifestyle factors and allergic diseases on lung function in 15-year-olds. Best subset selection was performed for linear regression models to investigate associations between 21 diverse early life events and current factors with spirometric parameters (forced vital capacity, forced expiratory volume in 1 s and maximal mid-expiratory flow (FEF 25-75 )) in 1326 participants of the German GINIplus and LISAplus birth cohorts. To reduce model complexity, one model for each spirometric parameter was replicated 1000 times in random subpopulations (N = 884). Only those factors that were included in >70% of the replication models were retained in the final analysis. A higher peak weight velocity and early lung infections were the early life events prevalently associated with airflow limitation and FEF 25-75 . Current environmental/lifestyle factors at age 15 years and allergic diseases that were associated with lung function were: indoor second-hand smoke exposure, vitamin D concentration, body mass index (BMI) and asthma status. Sex and height captured the majority of the explained variance (>75%), followed by BMI (≤23.7%). The variance explained by early life events was comparatively low (median: 4.8%; range: 0.2-22.4%), but these events were consistently negatively associated with airway function. Although the explained variance was mainly captured by well-known factors included in lung function prediction equations, our findings indicate early life and current factors that should be considered in studies on lung health among adolescents.
Intelligence is negatively associated with the number of functional somatic symptoms.
Kingma, E M; Tak, L M; Huisman, M; Rosmalen, J G M
2009-11-01
Functional somatic symptoms (FSS), that is, symptoms that cannot be conclusively explained by organic pathology, have a poorly understood aetiology. Intelligence was studied as a risk factor for FSS. It was hypothesised that intelligence is negatively associated with the number of FSS. To investigate the specific role of intelligence in FSS as opposed to medically explained symptoms (MES), the association of intelligence with FSS was compared with that of intelligence with MES. It was also hypothesised that lifestyle factors and socioeconomic factors mediate the relationship between intelligence and both FSS and MES, whereas psychological distress is especially important for FSS. All analyses were performed in a longitudinal study with two measurement waves in a general population cohort of 947 participants (age 33-79 years, 47.9% male). The Generalized Aptitude-Test Battery was used to derive an index for general intelligence, and the somatisation section of the Composite International Diagnostic Interview was used to measure the number of FSS and MES. General intelligence was significantly associated with the number of FSS. The association of intelligence and FSS but not MES was mediated by work situation: participants of lower intelligence who reported more FSS were more often (unwanted) economically inactive. No evidence was found for a mediating role of psychological distress in the association of intelligence with FSS, even though distress was an important predictor of FSS. Intelligence is negatively associated with the number of FSS in the general population. Part of the association of intelligence with FSS is explained by a more unfavourable work situation for adults of lower intelligence.
Schefers, J M; Weigel, K A; Rawson, C L; Zwald, N R; Cook, N B
2010-04-01
Data from lactating Holstein cows in herds that participate in a commercial progeny testing program were analyzed to explain management factors associated with herd-average conception and service rates on large commercial dairies. On-farm herd management software was used as the source of data related to production, reproduction, culling, and milk quality for 108 herds. Also, a survey regarding management, facilities, nutrition, and labor was completed on 86 farms. A total of 41 explanatory variables related to management factors and conditions that could affect conception and service rate were considered in this study. Models explaining conception and service rates were developed using a machine learning algorithm for constructing model trees. The most important explanatory variables associated with conception rate were the percentage of repeated inseminations between 4 and 17 d post-artificial insemination, stocking density in the breeding pen, length of the voluntary waiting period, days at pregnancy examination, and somatic cell score. The most important explanatory variables associated with service rate were the number of lactating cows per breeding technician, use of a resynchronization program, utilization of soakers in the holding area during the summer, and bunk space per cow in the breeding pen. The aforementioned models explained 35% and 40% of the observed variation in conception rate and service rate, respectively, and underline the association of herd-level management factors not strictly related to reproduction with herd reproductive performance. Copyright (c) 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Interpersonal Factors in Understanding and Treating Posttraumatic Stress Disorder
Markowitz, John C.; Milrod, Barbara; Bleiberg, Kathryn; Marshall, Randall D.
2010-01-01
Exposure to reminders of trauma underlies the theory and practice of most treatments for posttraumatic stress disorder (PTSD), yet exposure may not be the sole important treatment mechanism. Interpersonal features of PTSD influence its onset, chronicity, and possibly its treatment. The authors review interpersonal factors in PTSD, including the critical but underrecognized role of social support as both protective posttrauma and as a mechanism of recovery. They discuss interpersonal psychotherapy (IPT) as an alternative treatment for PTSD and present encouraging findings from two initial studies. Highlighting the potential importance of attachment and interpersonal relationships, the authors propose a mechanism to explain why improving relationships may ameliorate PTSD symptoms. PMID:19339847
Elwér, Sofia; Johansson, Klara; Hammarström, Anne
2014-03-10
Health consequences of the gender segregated labour market have previously been demonstrated in the light of gender composition of occupations and workplaces, with somewhat mixed results. Associations between the gender composition and health status have been suggested to be shaped by the psychosocial work environment. The present study aims to analyse how workplace gender composition is related to psychological distress and to explore the importance of the psychosocial work environment for psychological distress at workplaces with different gender compositions. The study population consisted of participants from the Northern Swedish Cohort with a registered workplace in 2007 when the participants were 42 years old (N=795). Questionnaire data were supplemented with register data on the gender composition of the participants' workplaces divided into three groups: workplaces with more women, mixed workplaces, and workplaces with more men. Associations between psychological distress and gender composition were analysed with multivariate logistic regression analysis adjusting for socioeconomic position, previous psychological distress, psychosocial work environment factors and gender. Logistic regression analyses (including interaction terms for gender composition and each work environment factor) were also used to assess differential associations between psychosocial work factor and psychological distress according to gender composition. Working at workplaces with a mixed gender composition was related to a higher likelihood of psychological distress compared to workplaces with more men, after adjustments for socioeconomic position, psychological distress at age 21, psychosocial work environment factors and gender. Psychosocial work environment factors did not explain the association between gender composition and psychological distress. The association between gender composition and psychological distress cannot be explained by differences in the perception of the psychosocial work environment and thus the work environment hypothesis is not supported. Workplaces with a mixed gender composition needs further research attention to explain the negative development of psychological distress during working life for both women and men at these workplaces.
2014-01-01
Background Health consequences of the gender segregated labour market have previously been demonstrated in the light of gender composition of occupations and workplaces, with somewhat mixed results. Associations between the gender composition and health status have been suggested to be shaped by the psychosocial work environment. The present study aims to analyse how workplace gender composition is related to psychological distress and to explore the importance of the psychosocial work environment for psychological distress at workplaces with different gender compositions. Methods The study population consisted of participants from the Northern Swedish Cohort with a registered workplace in 2007 when the participants were 42 years old (N = 795). Questionnaire data were supplemented with register data on the gender composition of the participants’ workplaces divided into three groups: workplaces with more women, mixed workplaces, and workplaces with more men. Associations between psychological distress and gender composition were analysed with multivariate logistic regression analysis adjusting for socioeconomic position, previous psychological distress, psychosocial work environment factors and gender. Logistic regression analyses (including interaction terms for gender composition and each work environment factor) were also used to assess differential associations between psychosocial work factor and psychological distress according to gender composition. Results Working at workplaces with a mixed gender composition was related to a higher likelihood of psychological distress compared to workplaces with more men, after adjustments for socioeconomic position, psychological distress at age 21, psychosocial work environment factors and gender. Psychosocial work environment factors did not explain the association between gender composition and psychological distress. Conclusions The association between gender composition and psychological distress cannot be explained by differences in the perception of the psychosocial work environment and thus the work environment hypothesis is not supported. Workplaces with a mixed gender composition needs further research attention to explain the negative development of psychological distress during working life for both women and men at these workplaces. PMID:24612791
Insufficiently studied factors related to burnout in nursing: Results from an e-Delphi study
2017-01-01
Objective This study aimed to identify potentially important factors in explaining burnout in nursing that have been insufficiently studied or ignored. Methods A three-round Delphi study via e-mail correspondence was conducted, with a group of 40 European experts. The e-Delphi questionnaire consisted of 52 factors identified from a literature review. Experts rated and scored the importance of factors in the occurrence of burnout and the degree of attention given by researchers to each of the variables listed, on a six-point Likert scale. We used the agreement percentage (>80%) to measure the level of consensus between experts. Furthermore, to confirm the level of consensus, we also calculated mean scores and modes. Regardless of the degree of consensus reached by the experts, we have calculated the mean of the stability of the answers for each expert (individual's qualitative stability) and the mean of the stability percentages of the experts (qualitative group stability). Results The response rate in the three rounds was 93.02% (n = 40). Eight new factors were suggested in the first round. After modified, the e-Delphi questionnaire in the second and third rounds had 60 factors. All the factors reached the third round with a consensus level above 80% in terms of the attention that researchers gave them in their studies. Moreover, the data show a total mean qualitative group stability of 96.21%. In the third round 9 factors were classified by experts as ‘studied very little’, 17 as ‘studied little’ and 34 as 'well studied' Conclusion Findings show that not all the factors that may influence nursing burnout have received the same attention from researchers. The panel of experts has identified factors that, although important in explaining burnout, have been poorly studied or even forgotten. Our results suggest that further study into factors such as a lack of recognition of part of the tasks that nurses perform, feminine stereotype or excessive bureaucracy is needed for a better understanding of this syndrome and improve the quality of life in nurses. PMID:28388660
Work factors and psychological distress in nurses' aides: a prospective cohort study
Eriksen, Willy; Tambs, Kristian; Knardahl, Stein
2006-01-01
Background Nurses' aides (assistant nurses), the main providers of practical patient care in many countries, are doing both emotional and heavy physical work, and are exposed to frequent social encounters in their job. There is scarce knowledge, though, of how working conditions are related to psychological distress in this occupational group. The aim of this study was to identify work factors that predict the level of psychological distress in nurses' aides. Methods The sample of this prospective study comprised 5076 Norwegian nurses' aides, not on leave when they completed a mailed questionnaire in 1999. Of these, 4076 (80.3 %) completed a second questionnaire 15 months later. A wide spectrum of physical, psychological, social, and organisational work factors were measured at baseline. Psychological distress (anxiety and depression) was assessed at baseline and follow-up by the SCL-5, a short version of Hopkins Symptom Checklist-25. Results In a linear regression model of the level of psychological distress at follow-up, with baseline level of psychological distress, work factors, and background factors as independent variables, work factors explained 2 % and baseline psychological distress explained 34 % of the variance. Exposures to role conflicts, exposures to threats and violence, working in apartment units for the aged, and changes in the work situation between baseline and follow-up that were reported to result in less support and encouragement were positively associated with the level of psychological distress. Working in psychiatric departments, and changes in the work situation between baseline and follow-up that gave lower work pace were negatively associated with psychological distress. Conclusion The study suggests that work factors explain only a modest part of the psychological distress in nurses' aides. Exposures to role conflicts and threats and violence at work may contribute to psychological distress in nurses' aides. It is important that protective measures against violent patients are implemented, and that occupational health officers offer victims of violence appropriate support or therapy. It is also important that health service organisations focus on reducing role conflicts, and that leaders listen to and consider the views of the staff. PMID:17132172
High Spending on Maternity Care in India: What Are the Factors Explaining It?
Goli, Srinivas; Moradhvaj; Rammohan, Anu; Shruti; Pradhan, Jalandhar
2016-01-01
High maternity-related health care spending is often cited as an important barrier in utilizing quality health care during pregnancy and childbirth. This study has two objectives: (i) to measure the levels of expenditure on total maternity care in disaggregated components such as ANCs, PNCs, and Natal care expenditure; (ii) to quantify the extent of catastrophic maternity expenditure (CME) incurred by households and identify the factors responsible for it. Data from the 71st round of the National Sample Survey (2014) was used to estimate maternity expenditure and its predictors. CME was measured as a share of consumption expenditure by different cut-offs. The two-part model was used to identify the factors associated with maternity spending and CME. The findings show that household spending on maternity care (US$ 149 in constant price) is much higher than previous estimates (US$ 50 in constant price). A significant proportion of households in India (51%) are incurring CME. Along with economic and educational status, type of health care and place of residence emerged as significant factors in explaining CME. Findings from this study assume importance in the context of an emerging demand for higher maternity entitlements and government spending on public health care in India. To reduce CME, India needs to improve the availability and accessibility of better-quality public health services and increase maternity entitlements in line with maternity expenditure identified in this study.
Mellone, Ugo; Klaassen, Raymond H. G.; García-Ripollés, Clara; Limiñana, Ruben; López-López, Pascual; Pavón, Diego; Strandberg, Roine; Urios, Vicente; Vardakis, Michalis; Alerstam, Thomas
2012-01-01
Background Performance of migrating birds can be affected by a number of intrinsic and extrinsic factors like morphology, meteorological conditions and migration strategies. We compared travel speeds of four raptor species during their crossing of the Sahara desert. Focusing the analyses on this region allows us to compare different species under equivalent conditions in order to disentangle which factors affect migratory performance. Methodology/Principal Finding We tracked raptors using GPS satellite transmitters from Sweden, Spain and Italy, and evaluated their migratory performance at both an hourly and a daily scale. Hourly data (flight speed and altitude for intervals of two hours) were analyzed in relation to time of day, species and season, and daily data (distance between roosting sites) in relation to species, season, day length and tailwind support. Conclusions/Significance Despite a clear variation in morphology, interspecific differences were generally very small, and did only arise in spring, with long-distance migrants (>5000 km: osprey and Western marsh-harrier) being faster than species that migrate shorter distances (Egyptian vulture and short-toed eagle). Our results suggest that the most important factor explaining hourly variation in flight speed is time of day, while at a daily scale, tailwind support is the most important factor explaining variation in daily distance, raising new questions about the consequences of possible future changes in worldwide wind patterns. PMID:22768314
vGNM: a better model for understanding the dynamics of proteins in crystals.
Song, Guang; Jernigan, Robert L
2007-06-08
The dynamics of proteins are important for understanding their functions. In recent years, the simple coarse-grained Gaussian Network Model (GNM) has been fairly successful in interpreting crystallographic B-factors. However, the model clearly ignores the contribution of the rigid body motions and the effect of crystal packing. The model cannot explain the fact that the same protein may have significantly different B-factors under different crystal packing conditions. In this work, we propose a new GNM, called vGNM, which takes into account both the contribution of the rigid body motions and the effect of crystal packing, by allowing the amplitude of the internal modes to be variables. It hypothesizes that the effect of crystal packing should cause some modes to be amplified and others to become less important. In doing so, vGNM is able to resolve the apparent discrepancy in experimental B-factors among structures of the same protein but with different crystal packing conditions, which GNM cannot explain. With a small number of parameters, vGNM is able to reproduce experimental B-factors for a large set of proteins with significantly better correlations (having a mean value of 0.81 as compared to 0.59 by GNM). The results of applying vGNM also show that the rigid body motions account for nearly 60% of the total fluctuations, in good agreement with previous findings.
Reynolds, Arthur J.; Temple, Judy A.; Ou, Suh-Ruu
2016-01-01
We investigated the extent to which cognitive and noncognitive skills accounted for the measured links between participation in preschool intervention and high school completion, highest grade completed, and incarceration history in early adulthood. Using data from the Chicago Longitudinal Study, an on-going 20-year investigation of the effects of the school-based Child-Parent Center early intervention program for over 1,500 children, we assessed the contribution of school readiness and achievement test scores up to age 14 and remedial education as well as measures of social adjustment, motivation, educational expectations, problem behavior, and juvenile arrest to the estimated direct effect of preschool. Hierarchical regression analysis indicated that when assessed separately, cognitive factors accounted for 42% of the preschool effect on high school completion, 37% on highest grade completed, and 23% on incarceration history by age 24 while noncognitive factors accounted for, respectively, 36%, 45%, and 59%. Together, cognitive and noncognitive factors explained 46%, 51%, and 59% of the main effect of preschool participation. The set of cognitive skills made greater value-added contributions to educational attainment while noncognitive skills made greater value-added contributions to incarceration history. Our findings support the important role of test scores, school performance, and social and motivational factors in explaining the effect of preschool participation on economically important indicators of well-being. PMID:27667885
Workers' compensation costs among construction workers: a robust regression analysis.
Friedman, Lee S; Forst, Linda S
2009-11-01
Workers' compensation data are an important source for evaluating costs associated with construction injuries. We describe the characteristics of injured construction workers filing claims in Illinois between 2000 and 2005 and the factors associated with compensation costs using a robust regression model. In the final multivariable model, the cumulative percent temporary and permanent disability-measures of severity of injury-explained 38.7% of the variance of cost. Attorney costs explained only 0.3% of the variance of the dependent variable. The model used in this study clearly indicated that percent disability was the most important determinant of cost, although the method and uniformity of percent impairment allocation could be better elucidated. There is a need to integrate analytical methods that are suitable for skewed data when analyzing claim costs.
The key kinematic determinants of undulatory underwater swimming at maximal velocity.
Connaboy, Chris; Naemi, Roozbeh; Brown, Susan; Psycharakis, Stelios; McCabe, Carla; Coleman, Simon; Sanders, Ross
2016-01-01
The optimisation of undulatory underwater swimming is highly important in competitive swimming performance. Nineteen kinematic variables were identified from previous research undertaken to assess undulatory underwater swimming performance. The purpose of the present study was to determine which kinematic variables were key to the production of maximal undulatory underwater swimming velocity. Kinematic data at maximal undulatory underwater swimming velocity were collected from 17 skilled swimmers. A series of separate backward-elimination analysis of covariance models was produced with cycle frequency and cycle length as dependent variables (DVs) and participant as a fixed factor, as including cycle frequency and cycle length would explain 100% of the maximal swimming velocity variance. The covariates identified in the cycle-frequency and cycle-length models were used to form the saturated model for maximal swimming velocity. The final parsimonious model identified three covariates (maximal knee joint angular velocity, maximal ankle angular velocity and knee range of movement) as determinants of the variance in maximal swimming velocity (adjusted-r2 = 0.929). However, when participant was removed as a fixed factor there was a large reduction in explained variance (adjusted r2 = 0.397) and only maximal knee joint angular velocity continued to contribute significantly, highlighting its importance to the production of maximal swimming velocity. The reduction in explained variance suggests an emphasis on inter-individual differences in undulatory underwater swimming technique and/or anthropometry. Future research should examine the efficacy of other anthropometric, kinematic and coordination variables to better understand the production of maximal swimming velocity and consider the importance of individual undulatory underwater swimming techniques when interpreting the data.
A Newly Identified Role of the Deciduous Forest Floor in the Timing of Green-Up
NASA Astrophysics Data System (ADS)
Lapenis, Andrei G.; Lawrence, Gregory B.; Buyantuev, Alexander; Jiang, Shiguo; Sullivan, Timothy J.; McDonnell, Todd C.; Bailey, Scott
2017-11-01
Plant phenology studies rarely consider controlling factors other than air temperature. We evaluate here the potential significance of physical and chemical properties of soil (edaphic factors) as additional important controls on phenology. More specifically, we investigate causal connections between satellite-observed green-up dates of small forest watersheds and soil properties in the Adirondack Mountains of New York, USA. Contrary to the findings of previous studies, where edaphic controls of spring phenology were found to be marginal, our analyses show that at least three factors manifest themselves as significant controls of seasonal patterns of variation in vegetated land surfaces observed from remote sensing: (1) thickness of the forest floor, (2) concentration of exchangeable soil potassium, and (3) soil acidity. For example, a thick forest floor appears to delay the onset of green-up. Watersheds with elevated concentrations of potassium are associated with early surface greening. We also found that trees growing in strongly acidified watersheds demonstrate delayed green-up dates. Overall, our work demonstrates that, at the scale of small forest watersheds, edaphic factors can explain a significant percentage of the observed spatial variation in land surface phenology that is comparable to the percentage that can be explained by climatic and landscape factors. We conclude that physical and chemical properties of forest soil play important roles in forest ecosystems as modulators of climatic drivers controlling the rate of spring soil warming and the transition of trees out of winter dormancy.
Pathophysiology of AAA: heredity vs environment.
Björck, Martin; Wanhainen, Anders
2013-01-01
Abdominal aortic aneurysm (AAA) has a complex pathophysiology, in which both environmental and genetic factors play important roles, the most important being smoking. The recently reported falling prevalence rates of AAA in northern Europe and Australia/New Zeeland are largely explained by healthier smoking habits. Dietary factors and obesity, in particular abdominal obesity, are also of importance. A family history of AAA among first-degree relatives is present in approximately 13% of incident cases. The probability that a monozygotic twin of a person with an AAA has the disease is 24%, 71 times higher than that for a monozygotic twin of a person without AAA. Approximately 1000 SNPs in 100 candidate genes have been studied, and three genome-wide association studies were published, identifying different diverse weak associations. An example of interaction between environmental and genetic factors is the effect of cholesterol, where genetic and dietary factors affect levels of both HDL and LDL. True epigenetic studies have not yet been published. Copyright © 2013 Elsevier Inc. All rights reserved.
Mehralizadeh, Semira; Dehdashti, Alireza; Motalebi Kashani, Masoud
2017-01-01
Statistics indicate a high risk of developing work-related musculoskeletal disorders among hospital nurses. The challenge is to understand the associations between musculoskeletal symptoms and various individual and occupational risk factors. This study examined the direct and indirect interactions of various risk factors with musculoskeletal complaints in hospital nurses. In a cross-sectional design, Iranian hospital nurses from Semnan University of Medical Sciences participated in a questionnaire survey reporting their perceived perceptions of various work-related risk factors and musculoskeletal symptoms. We tested our proposed structural equation model to evaluate the relations between latent and observed concepts and the relative importance and strength of exogenous variables in explaining endogenous musculoskeletal complaints. Measurement model fits the data relatively acceptable. Our findings showed direct effects of psychological, role-related and work posture stressors on musculoskeletal complaints. Fatigue mediated the adverse indirect relations of psychological, role-related, work posture and individual factors with musculoskeletal complaints. Structural equation modeling may provide methodological opportunities in occupational health research with a potential to explain the complexity of interactions among risk factors. Prevention of work-related musculoskeletal disorders among nurses must account for physical and psychosocial conditions.
Partnerships for optimizing organizational flexibility
Louis Poliquin
1999-01-01
For the purpose of this conference, I was asked to discuss partnerships in general. We will first review the reasons that bring organizations to enter into a collaborative agreement, then provide examples of different types of partnerships, discuss some factors that seem to explain the success of partnerships, and review important points to consider before preparing...
ERIC Educational Resources Information Center
Geijsel, Femke P.; Sleegers, Peter J. C.; Stoel, Reinoud D.; Kruger, Meta L.
2009-01-01
In this study we examined the relative importance of teachers' psychological states, school organizational conditions (teacher collaboration and participative decision making), and the leadership practices (vision, individual consideration, and intellectual stimulation) of principals at their schools in explaining variation in teachers'…
Gender and Gender Role Differences in Student-Teachers' Commitment to Teaching
ERIC Educational Resources Information Center
Moses, Ikupa; Admiraal, Wilfried F.; Berry, Amanda K.
2016-01-01
Low commitment to teaching amongst teachers is a problem facing the teaching profession in many countries. Gender might be an important factor in explaining what kinds of prospective teachers are attracted to teaching. This empirical study examined the relationship between student-teachers' gender, gender roles and commitment to teaching within…
ERIC Educational Resources Information Center
Mykkänen, Arttu; Määttä, Elina; Järvelä, Sanna
2016-01-01
Previous research has shown that observing peers' success in learning is important for the development of children's belief in themselves as learners. However, in research, these observations are seldom made in actual classroom learning activities. This study investigated how children explain factors that lead to their peers' successes in…
Severity of Victimization and Co-Occurring Mental Health Disorders among Substance Using Adolescents
ERIC Educational Resources Information Center
Sabri, Bushra
2012-01-01
Background: Co-occurring mental health disorders are widespread among substance using adolescents. Severity of victimization may be an important factor in explaining co-occurrence of mental health problems among adolescents with substance misuse problems. Purpose: The purpose of this study was to evaluate whether severe victimization experiences…
Changes in Situational and Dispositional Factors as Predictors of Job Satisfaction
ERIC Educational Resources Information Center
Keller, Anita C.; Semmer, Norbert K.
2013-01-01
Arguably, job satisfaction is one of the most important variables with regard to work. When explaining job satisfaction, research usually focuses on predictor variables in terms of levels but neglects growth rates. Therefore it remains unclear how potential predictors evolve over time and how their development affects job satisfaction. Using…
ERIC Educational Resources Information Center
Logan, Sarah; Medford, Emma; Hughes, Naomi
2011-01-01
The study examined how cognitive and motivational factors predicted reading skill and whether intrinsic reading motivation would explain significantly more variance in low ability readers' reading performance. One hundred and eleven children (aged 9-11) completed assessments of reading comprehension skill, verbal IQ, decoding skill and intrinsic…
More Value through Greater Differentiation: Gender Differences in Value Beliefs about Math
ERIC Educational Resources Information Center
Gaspard, Hanna; Dicke, Anna-Lena; Flunger, Barbara; Schreier, Brigitte; Häfner, Isabelle; Trautwein, Ulrich; Nagengast, Benjamin
2015-01-01
Expectancy-value theory (Eccles et al., 1983) is a prominent approach to explaining gender differences in math-related academic choices, with value beliefs acting as an important explanatory factor. Expectancy-value theory defines 4 value components: intrinsic value, attainment value, utility value, and cost. The present study followed up on…
ERIC Educational Resources Information Center
Hatlevik, Ove Edvard; Christophersen, Knut-Andreas
2013-01-01
During the last decade, information and communication technology has been given an increasingly large importance in our society. There seems to be a consensus regarding the necessity of supporting and developing school-based digital competence. In order to sustain digital inclusion, schools need to identify digital deficiencies and digital…
Characteristics of German hospitals adopting health IT systems - results from an empirical study.
Liebe, Jan-David; Egbert, Nicole; Frey, Andreas; Hübner, Ursula
2011-01-01
Hospital characteristics that facilitate IT adoption have been described by the literature extensively, however with controversial results. The aim of this study therefore is to draw a set of the most important variables from previous studies and include them in a combined analysis for testing their contribution as single factors and their interactions. Total number of IT systems installed and number of clinical IT systems in the hospital were used as criterion variables. Data from a national survey of German hospitals served as basis. Based on a stepwise multiple regression analysis four variables were identified to significantly explain the degree of IT adoption (60% explained variance): 1) hospital size, 2) IT department, 3) reference customer and 4) ownership (private vs. public). Our results replicate previous findings with regard to hospital size and ownership. In addition our study emphasizes the importance of a reliable internal structure for IT projects (existence of an IT department) and the culture of testing and installing most recent IT products (being a reference customer). None of the interactions between factors was significant.
Syphard, Alexandra D.; Keeley, Jon E.; Pfaff, Anne Hopkins; Ferschweiler, Ken
2017-01-01
Growing human and ecological costs due to increasing wildfire are an urgent concern in policy and management, particularly given projections of worsening fire conditions under climate change. Thus, understanding the relationship between climatic variation and fire activity is a critically important scientific question. Different factors limit fire behavior in different places and times, but most fire-climate analyses are conducted across broad spatial extents that mask geographical variation. This could result in overly broad or inappropriate management and policy decisions that neglect to account for regionally specific or other important factors driving fire activity. We developed statistical models relating seasonal temperature and precipitation variables to historical annual fire activity for 37 different regions across the continental United States and asked whether and how fire-climate relationships vary geographically, and why climate is more important in some regions than in others. Climatic variation played a significant role in explaining annual fire activity in some regions, but the relative importance of seasonal temperature or precipitation, in addition to the overall importance of climate, varied substantially depending on geographical context. Human presence was the primary reason that climate explained less fire activity in some regions than in others. That is, where human presence was more prominent, climate was less important. This means that humans may not only influence fire regimes but their presence can actually override, or swamp out, the effect of climate. Thus, geographical context as well as human influence should be considered alongside climate in national wildfire policy and management.
Algurén, Beatrix; Fridlund, Bengt; Cieza, Alarcos; Sunnerhagen, Katharina Stibrant; Christensson, Lennart
2012-01-01
In line with patient-centered health care, it is necessary to understand patients' perceptions of health. How stroke survivors perceive their health at different time points after stroke and which factors are associated with these feelings provide important information about relevant rehabilitation targets. This study aimed to identify the independent factors of health-related quality of life (HRQoL) from a biopsychosocial perspective using the methods of multivariate regression at 3 different time points poststroke. Included in the study were 99 patients from stroke units with diagnosed first-ever stroke. At admission and at 6 weeks, 3 months, and 1 year poststroke, HRQoL was assessed using the EuroQoL-5D Visual Analogue Scale (EQ-5D VAS). Consequences in Body Functions and Activities and Participation, and Environmental Factors were documented using 155 categories of the International Classification of Functioning, Disability and Health (ICF) Core Set for Stroke. For a period of 1 year, problems with recreation and leisure, personality functions, energy and drive functions, and gait pattern functions were repeatedly associated with worse HRQoL. Whereas Body Functions and Activities and Participation explained more than three-fourths of the variances of HRQoL at 6 weeks and 3 months (R² = 0.80-0.93), the variation at 1 year was best explained by either Body Functions or Environmental Factors (R² = 0.51). The results indicate the importance of Body Functions and Activities and Participation (mainly personality functions and recreation and leisure) on HRQoL within 3 months poststroke, but increased impact of Environmental Factors on HRQoL at 1 year.
Bolin, Kristian; Lindgren, Anna; Lindgren, Björn; Lundborg, Petter
2009-03-01
We analysed the relative importance of individual versus institutional factors in explaining variations in the utilisation of physician services among the 50+ in ten European countries. The importance of the latter was investigated, distinguishing between organisational (explicit) and cultural (implicit) institutional factors, by analysing the influence of supply side factors, such as physician density and physician reimbursement, and demand side factors, such as co-payment and gate-keeping, while controlling for a number of individual characteristics, using cross-national individual-level data from SHARE. Individual differences in health status accounted for about 50% of the between-country variation in physician visits, while the organisational and cultural factors considered each accounted for about 15% of the variation. The organisational variables showed the expected signs, with higher physician density being associated with more visits and higher co-payment, gate-keeping, and salary reimbursement being associated with less visits. When analysing specialist visits separately, however, organisational and cultural factors played a greater role, each accounting for about 30% of the between-country variation, whereas individual health differences only accounted for 11% of the variation.
Policy impacts of ecosystem services knowledge
Posner, Stephen M.; McKenzie, Emily; Ricketts, Taylor H.
2016-01-01
Research about ecosystem services (ES) often aims to generate knowledge that influences policies and institutions for conservation and human development. However, we have limited understanding of how decision-makers use ES knowledge or what factors facilitate use. Here we address this gap and report on, to our knowledge, the first quantitative analysis of the factors and conditions that explain the policy impact of ES knowledge. We analyze a global sample of cases where similar ES knowledge was generated and applied to decision-making. We first test whether attributes of ES knowledge themselves predict different measures of impact on decisions. We find that legitimacy of knowledge is more often associated with impact than either the credibility or salience of the knowledge. We also examine whether predictor variables related to the science-to-policy process and the contextual conditions of a case are significant in predicting impact. Our findings indicate that, although many factors are important, attributes of the knowledge and aspects of the science-to-policy process that enhance legitimacy best explain the impact of ES science on decision-making. Our results are consistent with both theory and previous qualitative assessments in suggesting that the attributes and perceptions of scientific knowledge and process within which knowledge is coproduced are important determinants of whether that knowledge leads to action. PMID:26831101
Jelenkovic, Aline; Ortega-Alonso, Alfredo; Rose, Richard J; Kaprio, Jaakko; Rebato, Esther; Silventoinen, Karri
2011-01-01
Human growth is a complex process that remains insufficiently understood. We aimed to analyze genetic and environmental influences on growth from late childhood to early adulthood. Two cohorts of monozygotic and dizygotic (same sex and opposite sex) Finnish twin pairs were studied longitudinally using self-reported height at 11-12, 14, and 17 years and adult age (FinnTwin12) and at 16, 17, and 18 years and adult age (FinnTwin16). Univariate and multivariate variance component models for twin data were used. From childhood to adulthood, genetic differences explained 72-81% of the variation of height in boys and 65-86% in girls. Environmental factors common to co-twins explained 5-23% of the variation of height, with the residual variation explained by environmental factors unique to each twin individual. Common environmental factors affecting height were highly correlated between the analyzed ages (0.72-0.99 and 0.91-1.00 for boys and girls, respectively). Genetic (0.58-0.99 and 0.70-0.99, respectively) and unique environmental factors (0.32-0.78 and 0.54-0.82, respectively) affecting height at different ages were more weakly, but still substantially, correlated. The genetic contribution to height is strong during adolescence. The high genetic correlations detected across the ages encourage further efforts to identify genes affecting growth. Common and unique environmental factors affecting height during adolescence are also important, and further studies are necessary to identify their nature and test whether they interact with genetic factors. Copyright © 2011 Wiley-Liss, Inc.
Tmd Factorization and Evolution for Tmd Correlation Functions
NASA Astrophysics Data System (ADS)
Mert Aybat, S.; Rogers, Ted C.
We discuss the application of transverse momentum dependent (TMD) factorization theorems to phenomenology. Our treatment relies on recent extensions of the Collins-Soper-Sterman (CSS) formalism. Emphasis is placed on the importance of using well-defined TMD parton distribution functions (PDFs) and fragmentation functions (FFs) in calculating the evolution of these objects. We explain how parametrizations of unpolarized TMDs can be obtained from currently existing fixed-scale Gaussian fits and previous implementations of the CSS formalism in the Drell-Yan process, and provide some examples. We also emphasize the importance of agreed-upon definitions for having an unambiguous prescription for calculating higher orders in the hard part, and provide examples of higher order calculations. We end with a discussion of strategies for extending the phenomenological applications of TMD factorization to situations beyond the unpolarized case.
Environmental controls of marine productivity hot spots around Antarctica
NASA Astrophysics Data System (ADS)
Arrigo, Kevin R.; van Dijken, Gert L.; Strong, Aaron L.
2015-08-01
Antarctic coastal polynyas are biologically rich ecosystems that support large populations of mammals and birds and are globally significant sinks of atmospheric carbon dioxide. To support local phytoplankton blooms, these highly productive ecosystems require a large input of iron (Fe), the sources of which are poorly known. Here we assess the relative importance of six different environmental factors in controlling the amount of phytoplankton biomass and rates of net primary production (NPP) in 46 coastal polynyas around Antarctica. Data presented here suggest that melting ice shelves are a primary supplier of Fe to coastal polynyas, with basal melt rates explaining 59% of the between-polynya variance in mean chlorophyll a (Chl a) concentration. In a multiple regression analysis, which explained 78% of the variance in chlorophyll a (Chl a) between polynyas, basal melt rate explained twice as much of the variance as the next most important variable. Fe upwelled from sediments, which is partly controlled by continental shelf width, was also important in some polynyas. Of secondary importance to phytoplankton abundance and NPP were sea surface temperature and polynya size. Surprisingly, differences in light availability and the length of the open water season explained little or none of the variance in either Chl a or NPP between polynyas. If the productivity of coastal polynyas is indeed sensitive to the release of Fe from melting ice shelves, future changes in ice shelf melt rates could dramatically influence Antarctic coastal ecosystems and the ability of continental shelf waters to sequester atmospheric carbon dioxide. This article was corrected on 26 AUG 2015. See the end of the full text for details.
Mehrotra, R; Norris, K
2010-11-01
In the United States, there are significant racial disparities in the incidence and prevalence of end-stage renal disease. The disparities are greatest for the Blacks and the magnitude of disparity is significantly greater than is evident from the incidence and prevalence data of end-stage renal disease - early stage chronic kidney disease is less common in Blacks and during that stage, mortality rate is significantly higher for that racial group. Recent studies have identified a genetic predisposition for non-diabetic renal disease among Blacks. However, genetic factors explain only part of the higher risk and the racial disparities are a result of a complex interplay of biology and sociology. Herein we focus on two factors and their role in explaining the higher risk for progression of chronic kidney disease among Blacks - one biologic (vitamin D deficiency) and one sociologic (neighborhood poverty). A greater Understanding of these factors is important in order to reduce the racial disparities in the United States.
Brittain, Kelly; Christy, Shannon M; Rawl, Susan M
2016-02-01
African Americans have higher colorectal cancer (CRC) mortality rates. Research suggests that CRC screening interventions targeting African Americans be based upon cultural dimensions. Secondary analysis of data from African-Americans who were not up-to-date with CRC screening (n=817) was conducted to examine: 1) relationships among cultural factors (i.e., provider trust, cancer fatalism, health temporal orientation (HTO)), health literacy, and CRC knowledge; 2) age and gender differences; and 3) relationships among the variables and CRC screening intention. Provider trust, fatalism, HTO, health literacy and CRC knowledge had significant relationships among study variables. The FOBT intention model explained 43% of the variance with age and gender being significant predictors. The colonoscopy intention model explained 41% of the variance with gender being a significant predictor. Results suggest that when developing CRC interventions for African Americans, addressing cultural factors remain important, but particular attention should be given to the age and gender of the patient.
Johnson, Benjamin N.; Ashe, Melinda L.; Wilson, Stephen J.
2017-01-01
Borderline personality disorder (BPD) and alcohol use disorder (AUD) share impulsivity as an etiological factor. However, impulsivity is ill-defined, often overlapping with self-control capacity. This study attempts to disentangle these constructs and their associations with alcohol use and BPD. Undergraduates (N = 192) completed the Five Factor Model Rating Form, which generated two dimensional scales of BPD, the Self-Control Scale, the UPPS-P (self-reported impulsivity), and the Stop-signal and delay discounting tasks (laboratory-measured impulsivity). Self-control appeared as a major predictor of BPD features and drinking, explaining as much or more variance in outcome than impulsivity. Co-occurrence of elevated BPD features and problem drinking was also best explained by self-control. Laboratory measures of impulsivity were not correlated with BPD scales or alcohol use. Self-regulatory capacity may be an important but overlooked factor in BPD and alcohol use and should be considered alongside impulsivity in future research. PMID:27064849
Stress-related sickness absence and return to labour market in Sweden.
Engström, Lars-Gunnar; Janson, Staffan
2007-03-15
To analyse factors influencing chances of returning to work after long-term sickness absence with a stress-related psychiatric diagnosis. Primary focus is on employer- and occupational categories as explanatory variables. Data was collected from the regional social insurance office in the county of Värmland for 911 individuals, all with stress-related sickness absences during November in the year 2000. Logistic regressions were carried out on outcome states from long-term sickness absence on two follow-up occasions after two and three years. The results indicate that the employer- and occupational categories only had a minor effect on return to work after the long-term sickness absence. Age and health-related factors together with time factors seem to be more relevant in explaining return to work. The findings suggest that individual labour market position, as occupation, employer, branch etc, seems to be less important than expected in explaining return to work from sickness absence due to stress-related psychiatric disorders.
[Atherosclerosis in inflammatory diseases].
Páramo, José A; Rodríguez, José A; Orbe, Josune
2007-05-19
The recognition that inflammation is a hallmark of atherosclerotic disease and its complications has led to a series of studies reporting high prevalence of atherosclerosis in chronic inflammatory diseases. Indeed, chronic immune diseases, such as systemic lupus erythematosus and rheumatoid arthritis, are associated with proinflammation, accelerated atherosclerosis and increased incidence of cardiovascular disease. Since the susceptibility towards cardiovascular events cannot be explained by classical risk factors, disease-specific pathways have been put forward as additional risk factors, potentially important for future prevention and treatment of atherosclerosis associated with chronic inflammatory diseases.
Detailed analysis of the self-discharge of supercapacitors
NASA Astrophysics Data System (ADS)
Kowal, Julia; Avaroglu, Esin; Chamekh, Fahmi; Šenfelds, Armands; Thien, Tjark; Wijaya, Dhanny; Sauer, Dirk Uwe
Self-discharge is an important performance factor when using supercapacitors. Voltage losses in the range of 5-60% occur over two weeks. Experiments show a dependency of the self-discharge rate on various parameters such as temperature, charge duration and short-term history. In this paper, self-discharge of three commercially available supercapacitors was measured under various conditions. Based on different measurements, the impact of the influence factors is identified. A simple model to explain parts of the voltage decay is presented.
Takeuchi, Hikaru; Kawashima, Ryuta
2016-12-01
Human psychometric intelligence can predict a number of important social and academic outcomes. Substantial parts of the variances of human intelligence and the brain volume supporting those abilities are explained by environmental factors, and during childhood, human brains have higher plasticity and also 60% of variance of intelligence that is explained by environmental factors. Here, we review the representative environmental factors known to affect human intellectual development during each developmental stage. We describe what is (and what is not) being investigated to determine how these factors affect human brain development through analyses of volumetrical and cortical structures. In conclusion, environmental factors that affect children's intellectual development lead to three patterns of brain structural change. The first is global change in the brain structure, observed more often in the earlier phase of development. The second is structural changes concentrated in the medial prefrontal and adjacent areas and medial temporal areas, which are likely to be induced by stress in many cases. The third is sporadic region-specific change, likely to be primarily caused by use-dependent plasticity of the areas that is often observed in the later phase of development. These changes may underlie the alterations in children's intellectual development that is induced by environmental factors. © The Author(s) 2015.
Aagestad, Cecilie; Tyssen, Reidar; Sterud, Tom
2016-03-08
Doctor -certified sick leave is prevalent in the health and social sector. We examined whether the higher risk of doctor-certified sick leave in women in health and social occupations compared to women in other occupations was explained by particular work-related psychosocial and mechanical risk factors. A randomly drawn cohort aged 18-69 years from the general population in Norway was surveyed in 2009 (n = 12,255, response at baseline = 60.9 %), and was followed up in the national registry of social transfer payments in 2010. Eligible respondents were women registered with an active employee relationship for ≥100 actual working days in 2009 and 2010 (n = 3032). Using this sample, we compared health and social workers (n = 661) with the general working population (n = 2371). The outcome of interest was long-term sick leave (LTSL) ≥21 working days during 2010. Eight psychosocial and eight mechanical factors were evaluated. After adjusting for age, previous LTSL, education and working hours/week, women in health and social occupations had a higher risk for LTSL compared with women in the general working population (OR = 1.42, 95 % CI = 1.13-1.79; p = 0.003). After adjusting for psychosocial and mechanical factors, 70 % of the excess risk for LTSL was explained compared with the initial model. The main contributory factors to the increased risk were threats of violence and violence, emotional demands and awkward lifting. Psychosocial and mechanical factors explained much of the excess risk for LTSL in women in health and social occupations compared with working women in general. Psychosocial risk factors were the most important contributors.
NASA Astrophysics Data System (ADS)
Ahmadia, Gabby N.; Tornabene, Luke; Smith, David J.; Pezold, Frank L.
2018-03-01
Factors shaping coral-reef fish species assemblages can operate over a wide range of spatial scales (local versus regional) and across both proximate and evolutionary time. Niche theory and neutral theory provide frameworks for testing assumptions and generating insights about the importance of local versus regional processes. Niche theory postulates that species assemblages are an outcome of evolutionary processes at regional scales followed by local-scale interactions, whereas neutral theory presumes that species assemblages are formed by largely random processes drawing from regional species pools. Indo-Pacific cryptobenthic coral-reef fishes are highly evolved, ecologically diverse, temporally responsive, and situated on a natural longitudinal diversity gradient, making them an ideal group for testing predictions from niche and neutral theories and effects of regional and local processes on species assemblages. Using a combination of ecological metrics (fish density, diversity, assemblage composition) and evolutionary analyses (testing for phylogenetic niche conservatism), we demonstrate that the structure of cryptobenthic fish assemblages can be explained by a mixture of regional factors, such as the size of regional species pools and broad-scale barriers to gene flow/drivers of speciation, coupled with local-scale factors, such as the relative abundance of specific microhabitat types. Furthermore, species of cryptobenthic fishes have distinct microhabitat associations that drive significant differences in assemblage community structure between microhabitat types, and these distinct microhabitat associations are phylogenetically conserved over evolutionary timescales. The implied differential fitness of cryptobenthic fishes across varied microhabitats and the conserved nature of their ecology are consistent with predictions from niche theory. Neutral theory predictions may still hold true for early life-history stages, where stochastic factors may be more important in explaining recruitment. Overall, through integration of ecological and evolutionary techniques, and using multiple spatial scales, our study offers a unique perspective on factors determining coral-reef fish assemblages.
Major psychological factors affecting acceptance of gene-recombination technology.
Tanaka, Yutaka
2004-12-01
The purpose of this study was to verify the validity of a causal model that was made to predict the acceptance of gene-recombination technology. A structural equation model was used as a causal model. First of all, based on preceding studies, the factors of perceived risk, perceived benefit, and trust were set up as important psychological factors determining acceptance of gene-recombination technology in the structural equation model. An additional factor, "sense of bioethics," which I consider to be important for acceptance of biotechnology, was added to the model. Based on previous studies, trust was set up to have an indirect influence on the acceptance of gene-recombination technology through perceived risk and perceived benefit in the model. Participants were 231 undergraduate students in Japan who answered a questionnaire with a 5-point bipolar scale. The results indicated that the proposed model fits the data well, and showed that acceptance of gene-recombination technology is explained largely by four factors, that is, perceived risk, perceived benefit, trust, and sense of bioethics, whether the technology is applied to plants, animals, or human beings. However, the relative importance of the four factors was found to vary depending on whether the gene-recombination technology was applied to plants, animals, or human beings. Specifically, the factor of sense of bioethics is the most important factor in acceptance of plant gene-recombination technology and animal gene-recombination technology, and the factors of trust and perceived risk are the most important factors in acceptance of human being gene-recombination technology.
Alkarkhi, Abbas F M; Ramli, Saifullah Bin; Easa, Azhar Mat
2009-01-01
Major (sodium, potassium, calcium, magnesium) and minor elements (iron, copper, zinc, manganese) and one heavy metal (lead) of Cavendish banana flour and Dream banana flour were determined, and data were analyzed using multivariate statistical techniques of factor analysis and discriminant analysis. Factor analysis yielded four factors explaining more than 81% of the total variance: the first factor explained 28.73%, comprising magnesium, sodium, and iron; the second factor explained 21.47%, comprising only manganese and copper; the third factor explained 15.66%, comprising zinc and lead; while the fourth factor explained 15.50%, comprising potassium. Discriminant analysis showed that magnesium and sodium exhibited a strong contribution in discriminating the two types of banana flour, affording 100% correct assignation. This study presents the usefulness of multivariate statistical techniques for analysis and interpretation of complex mineral content data from banana flour of different varieties.
Explaining Australian immigration.
Betts, K
1996-11-01
"This article reviews the post-Second World War literature on explanations for Australia's immigration program. It discovers three main schools of thought based on net pull factors: the official explanation and two unofficial explanations which focus on migrants as workers and on migrants as consumers. However the growing importance of net push factors after 1974 means that some of this work is less relevant today. Explanations focusing on net push factors have yet to cohere into a distinct perspective (or perspectives) but some research has been done on chain migration and family-based migration strategies, asylum seekers, temporary movement, and migration and the law." excerpt
Zhang, Yong-Hua; Wang, Ian J.; Comes, Hans Peter; Peng, Hua; Qiu, Ying-Xiong
2016-01-01
Examining how historical and contemporary geographic and environmental factors contribute to genetic divergence at different evolutionary scales is a central yet largely unexplored question in ecology and evolution. Here, we examine this key question by investigating how environmental and geographic factors across different epochs have driven genetic divergence at deeper (phylogeographic) and shallower (landscape genetic) evolutionary scales in the Chinese Tertiary relict tree Emmenopterys henryi. We found that geography played a predominant role at all levels – phylogeographic clades are broadly geographically structured, the deepest levels of divergence are associated with major geological or pre-Quaternary climatic events, and isolation by distance (IBD) primarily explained population genetic structure. However, environmental factors are clearly also important – climatic fluctuations since the Last Interglacial (LIG) have likely contributed to phylogeographic structure, and the population genetic structure (in our AFLP dataset) was partly explained by isolation by environment (IBE), which may have resulted from natural selection in environments with divergent climates. Thus, historical and contemporary geography and historical and contemporary environments have all shaped patterns of genetic structure in E. henryi, and, in fact, changes in the landscape through time have also been critical factors. PMID:27137438
Zhang, Yong-Hua; Wang, Ian J; Comes, Hans Peter; Peng, Hua; Qiu, Ying-Xiong
2016-05-03
Examining how historical and contemporary geographic and environmental factors contribute to genetic divergence at different evolutionary scales is a central yet largely unexplored question in ecology and evolution. Here, we examine this key question by investigating how environmental and geographic factors across different epochs have driven genetic divergence at deeper (phylogeographic) and shallower (landscape genetic) evolutionary scales in the Chinese Tertiary relict tree Emmenopterys henryi. We found that geography played a predominant role at all levels - phylogeographic clades are broadly geographically structured, the deepest levels of divergence are associated with major geological or pre-Quaternary climatic events, and isolation by distance (IBD) primarily explained population genetic structure. However, environmental factors are clearly also important - climatic fluctuations since the Last Interglacial (LIG) have likely contributed to phylogeographic structure, and the population genetic structure (in our AFLP dataset) was partly explained by isolation by environment (IBE), which may have resulted from natural selection in environments with divergent climates. Thus, historical and contemporary geography and historical and contemporary environments have all shaped patterns of genetic structure in E. henryi, and, in fact, changes in the landscape through time have also been critical factors.
The Relationship between Social Capital in Hospitals and Physician Job Satisfaction
Ommen, Oliver; Driller, Elke; Köhler, Thorsten; Kowalski, Christoph; Ernstmann, Nicole; Neumann, Melanie; Steffen, Petra; Pfaff, Holger
2009-01-01
Background Job satisfaction in the hospital is an important predictor for many significant management ratios. Acceptance in professional life or high workload are known as important predictors for job satisfaction. The influence of social capital in hospitals on job satisfaction within the health care system, however, remains to be determined. Thus, this article aimed at analysing the relationship between overall job satisfaction of physicians and social capital in hospitals. Methods The results of this study are based upon questionnaires sent by mail to 454 physicians working in the field of patient care in 4 different German hospitals in 2002. 277 clinicians responded to the poll, for a response rate of 61%. Analysis was performed using three linear regression models with physician overall job satisfaction as the dependent variable and age, gender, professional experience, workload, and social capital as independent variables. Results The first regression model explained nearly 9% of the variance of job satisfaction. Whereas job satisfaction increased slightly with age, gender and professional experience were not identified as significant factors to explain the variance. Setting up a second model with the addition of subjectively-perceived workload to the analysis, the explained variance increased to 18% and job satisfaction decreased significantly with increasing workload. The third model including social capital in hospital explained 36% of the variance with social capital, professional experience and workload as significant factors. Conclusion This analysis demonstrated that the social capital of an organisation, in addition to professional experience and workload, represents a significant predictor of overall job satisfaction of physicians working in the field of patient care. Trust, mutual understanding, shared aims, and ethical values are qualities of social capital that unify members of social networks and communities and enable them to act cooperatively. PMID:19445692
Kvarnemo, Charlotta
2018-04-23
Why do some animals mate with one partner rather than many? Here, I investigate factors related to (i) spatial constraints (habitat limitation, mate availability), (ii) time constraints (breeding synchrony, length of breeding season), (iii) need for parental care, and (iv) genetic compatibility, to see what support can be found in different taxa regarding the importance of these factors in explaining the occurrence of monogamy, whether shown by one sex (monogyny or monandry) or by both sexes (mutual monogamy). Focusing on reproductive rather than social monogamy whenever possible, I review the empirical literature for birds, mammals and fishes, with occasional examples from other taxa. Each of these factors can explain mating patterns in some taxa, but not in all. In general, there is mixed support for how well the factors listed above predict monogamy. The factor that shows greatest support across taxa is habitat limitation. By contrast, while a need for parental care might explain monogamy in freshwater fishes and birds, there is clear evidence that this is not the case in marine fishes and mammals. Hence, reproductive monogamy does not appear to have a single overriding explanation, but is more taxon specific. Genetic compatibility is a promising avenue for future work likely to improve our understanding of monogamy and other mating patterns. I also discuss eight important consequences of reproductive monogamy: (i) parentage, (ii) parental care, (iii) eusociality and altruism, (iv) infanticide, (v) effective population size, (vi) mate choice before mating, (vii) sexual selection, and (viii) sexual conflict. Of these, eusociality and infanticide have been subject to debate, briefly summarised herein. A common expectation is that monogamy leads to little sexual conflict and no or little sexual selection. However, as reviewed here, sexual selection can be substantial under mutual monogamy, and both sexes can be subject to such selection. Under long-term mutual monogamy, mate quality is obviously more important than mate numbers, which in turn affects the need for pre-mating mate choice. Overall, I conclude that, despite much research on genetic mating patterns, reproductive monogamy is still surprisingly poorly understood and further experimental and comparative work is needed. This review identifies several areas in need of more data and also proposes new hypotheses to test. © 2018 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.
ERIC Educational Resources Information Center
Li, Dongping; Bao, Zhenzhou; Li, Xian; Wang, Yanhui
2016-01-01
Background: School factors play important roles in adolescent suicide. However, little is known about how school climate is associated with adolescent suicide. This study examined the relationship between perceived school climate and adolescent suicidal ideation and suicide attempts, and whether these relations were explained by adolescent sleep…
"Free in Time, Not Free in Mind": First-Year University Students Becoming More Independent
ERIC Educational Resources Information Center
Ding, Feng
2017-01-01
In school-to-university transition literature, autonomy has been implied or explicitly explained as an important factor to predict the persistence and engagement of students in higher education; however, little qualitative research addresses students' transition in relation to autonomy, what these students have to go through in terms of becoming…
Adolescents' Psychological Well-Being and Self-Esteem in the Context of Relationships at School
ERIC Educational Resources Information Center
Sarkova, Maria; Bacikova-Sleskova, Maria; Madarasova Geckova, Andrea; Katreniakova, Zuzana; van den Heuvel, Wim; van Dijk, Jitse P.
2014-01-01
Background: The school environment has shown itself to be an important factor in explaining adolescent behaviour. The relationships and experiences that pupils have at school have been found to influence their development, psychological well-being, self-esteem and social adjustment. Purpose: The aim of the study is to explore whether there is a…
ERIC Educational Resources Information Center
Buckland, Jerry
2010-01-01
This article argues that financial literacy varies across socioeconomic groups and their neighborhoods, in part because of the adult learning that occurs within a local context. The study begins by explaining that financial literacy needs vary across socioeconomic groups and that there are important structural factors affecting the financial…
Sources from a Somerset Village: A Model for Informal Learning about Radiation and Radioactivity.
ERIC Educational Resources Information Center
Alsop, Steve; Watts, Mike
1997-01-01
Research on conceptual change emphasizes the importance of factors in the cognitive domain. This research argues that models of conceptual change learning should also encompass issues of affect, conation, and self-esteem. The use of these expressions is explained via four case studies on members of a rural village concerning informal learning…
Gender Diversity Policies in Universities: A Multi-Perspective Framework of Policy Measures
ERIC Educational Resources Information Center
Timmers, Tanya M.; Willemsen, Tineke M.; Tijdens, Kea G.
2010-01-01
Are policies to increase women's share among university professors effective? The importance of gender equality on the labor market has been well established, but our understanding of what kind of policy is effective to increase the share of women is still unclear. Three sets of factors explain women's low shares at higher job levels, notably…
An Empirical Analysis of Differences in GDP per Capita and the Role of Human Capital
ERIC Educational Resources Information Center
Sfakianakis, George; Magoutas, Anastasios I.; Georgopoulos, Demosthenes
2010-01-01
Using a generalized production function approach and insights from empirical research on the determinants of growth, this paper assesses the relative importance of specific factors in explaining differences in the levels of per capita GDP. Emphasis is placed on education, physical capital accumulation, the share of the public sector in economic…
ERIC Educational Resources Information Center
Consedine, Nathan S.; Windsor, John A.
2014-01-01
Mismatches between the needs of public health systems and student interests have led to renewed study on the factors predicting career specializations among medical students. While most work examines career and lifestyle values, emotional proclivities may be important; disgust sensitivity may help explain preferences for careers with greater and…
ERIC Educational Resources Information Center
Castro, Juan F.; Yamada, Gustavo; Arias, Omar
2016-01-01
This paper analyzes the relative importance of short-term financial constraints "vis-a-vis" skills and other background factors when explaining higher education access in Peru. We focus on the disparities in university enrollment between rich and poor households. We use a novel household survey that includes special tests to measure…
American Indian Women and Screening Mammography: Findings from a Qualitative Study in Oklahoma
ERIC Educational Resources Information Center
Tolma, Eleni; Batterton, Chasity; Hamm, Robert M.; Thompson, David; Engelman, Kimberly K.
2012-01-01
Background: Breast cancer is an important public health issue within the American Indian (AI) community in Oklahoma; however, there is limited information to explain the low screening mammography rates among AI women. Purpose: To identify the motivational factors affecting an AI woman's decision to obtain a mammogram. Methods: Through the use of…
J. Amy Belaire; Lynne M. Westphal; Emily S. Minor
2016-01-01
The conservation value of residential landscapes is becoming increasingly apparent in our urbanizing world. The ecological characteristics of residential areas are largely determined by the decisions of many individual "managers." In these complex socio-ecological systems, it is important to understand the factors that motivate human decision-making. Our...
Ibfelt, E H; Kjær, S K; Høgdall, C; Steding-Jessen, M; Kjær, T K; Osler, M; Johansen, C; Frederiksen, K; Dalton, S O
2013-01-01
Background: In an attempt to decrease social disparities in cancer survival, it is important to consider the mechanisms by which socioeconomic position influences cancer prognosis. We aimed to investigate whether any associations between socioeconomic factors and survival after cervical cancer could be explained by socioeconomic differences in cancer stage, comorbidity, lifestyle factors or treatment. Methods: We identified 1961 cases of cervical cancer diagnosed between 2005 and 2010 in the Danish Gynaecological Cancer database, with information on prognostic factors, treatment and lifestyle. Age, vital status, comorbidity and socioeconomic data were obtained from nationwide administrative registers. Associations between socioeconomic indicators (education, income and cohabitation status) and mortality by all causes were analysed in Cox regression models with inclusion of possible mediators. Median follow-up time was 3.0 years (0.01–7.0). Results: All cause mortality was higher in women with shorter rather than longer education (hazard ratio (HR), 1.46; 1.20–1.77), among those with lower rather than higher income (HR, 1.32; 1.07–1.63) and among women aged<60 years without a partner rather than those who cohabited (HR, 1.60; 1.29–1.98). Socioeconomic differences in survival were partly explained by cancer stage and less by comorbidity or smoking (stage- and comorbidty- adjusted HRs being 1.07; 0.96–1.19 for education and 1.15; 0.86–1.52 for income). Conclusion: Socioeconomic disparities in survival after cervical cancer were partly explained by socioeconomic differences in cancer stage. The results point to the importance of further investigations into reducing diagnosis delay among disadvantaged groups. PMID:24030072
NASA Astrophysics Data System (ADS)
Pigeon, Karine E.; Anderson, Meghan; MacNearney, Doug; Cranston, Jerome; Stenhouse, Gordon; Finnegan, Laura
2016-11-01
Populations of boreal and southern mountain caribou in Alberta, Canada, are declining, and the ultimate cause of their decline is believed to be anthropogenic disturbance. Linear features are pervasive across the landscape, and of particular importance, seismic lines established in the 1900s (legacy seismic lines) are slow to regenerate. Off-highway vehicles are widely used on these seismic lines and can hamper vegetative re-growth because of ongoing physical damage, compaction, and active clearing. Restoration of seismic lines within caribou range is therefore a priority for the recovery of threatened populations in Alberta, but a triage-type approach is necessary to prioritize restoration and ensure conservation resources are wisely spent. To target restoration efforts, our objective was to determine factors that best explained levels of off-highway vehicles use on seismic lines intersecting roads. We investigated the relative importance of local topography, vegetation attributes of seismic lines, and broad-scale human factors such as the density of infrastructures and the proximity to recreation campsites and towns to explain the observed levels of off-highway vehicles use. We found that off-highway vehicles use was mainly associated with local topography and vegetation attributes of seismic lines that facilitated ease-of-travel. Broad-scale landscape attributes associated with industrial, recreation access, or hunting activities did not explain levels of off-highway vehicles use. Management actions aimed at promoting natural regeneration and reduce ease-of-travel on legacy seismic lines within caribou ranges can be beneficial to caribou recovery in Alberta, Canada, and we therefore recommend restrictions of off-highway vehicles use on low vegetation, dry seismic lines in caribou ranges.
Magee, Joshua C.; Teachman, Bethany A.
2007-01-01
The current study examined the nature and consequences of attributions about unsuccessful thought suppression. Undergraduate students with either high (N=67) or low (N=59) levels of obsessive-compulsive symptoms rated attributions to explain their unsuccessful thought suppression attempts. We expected that self-blaming attributions and attributions ascribing importance to unwanted thoughts would predict more distress and greater recurrence of thoughts during time spent monitoring or suppressing unwanted thoughts. Further, we expected that these attributions would mediate the relationship between obsessive-compulsive symptom levels and the negative thought suppression outcomes (distress and thought recurrence). Structural equation models largely confirmed the hypotheses, suggesting that attributions may be an important factor in explaining the consequences of thought suppression. Implications are discussed for cognitive theories of obsessive-compulsive disorder and thought suppression. PMID:17825786
The Influence of Contextual and Psychosocial Factors on Handwashing.
Seimetz, Elisabeth; Boyayo, Anne-Marie; Mosler, Hans-Joachim
2016-06-01
Even though washing hands with soap is among the most effective measures to reduce the risk of infection, handwashing rates in infrastructure-restricted settings remain seriously low. Little is known about how context alone and in interaction with psychosocial factors influence hand hygiene behavior. The aim of this article was to explore how both contextual and psychosocial factors affect handwashing practices. A cross-sectional survey was conducted with 660 caregivers of primary school children in rural Burundi. Hierarchical regression analyses revealed that household wealth, the amount of water per person, and having a designated place for washing hands were contextual factors significantly predicting handwashing frequency, whereas the contextual factors, time spent collecting water and amount of money spent on soap, were not significant predictors. The contextual factors explained about 13% of the variance of reported handwashing frequency. The addition of the psychosocial factors to the regression model resulted in a significant 41% increase of explained variation in handwashing frequency. In this final model, the amount of water was the only contextual factor that remained a significant predictor. The most important predictors were a belief of self-efficacy, planning how, when, and where to wash hands, and always remembering to do so. The findings suggest that contextual constraints might be perceived rather than actual barriers and highlight the role of psychosocial factors in understanding hygiene behaviors. © The American Society of Tropical Medicine and Hygiene.
NASA Astrophysics Data System (ADS)
Wu, Xiaodong; Fang, Hongbing; Zhao, Yonghua; Smoak, Joseph M.; Li, Wangping; Shi, Wei; Sheng, Yu; Zhao, Lin; Ding, Yongjian
2017-07-01
Many investigations of the preservation of soil organic carbon (SOC) in permafrost regions have examined roles of geomorphology, pedogenesis, vegetation cover, and permafrost within particular regions. However, it is difficult to disentangle the effects of multiple factors on the SOC in permafrost regions due to the heterogeneity in environmental conditions. Based on data from 73 soil study sites in permafrost regions of the eastern Qinghai-Tibetan Plateau, we developed a simple conceptual model, which relates SOC to topography, vegetation, and pedogenesis. We summarized the dominant factors and their controls on SOC using 31 measured soil physiochemical variables. Soil texture explains approximately 60% of the variations in the SOC stocks for the upper 0-2 m soil. Soil particle size closely correlates to soil moisture, which is an important determinant of SOC. Soil salinity and cations are important factors as well and can explain about 10% of the variations in SOC. The SOC and total nitrogen (TN) stocks for the 1-2 m depths have larger uncertainties than those of upper 1 m soil layer. The vegetation, pH, and bulk density mainly affects SOC and TN stocks for the upper 1 m soil layers, while the active layer thickness and soil particle size have greater influence on SOC and TN stocks for the 1-2 m soils. Our results suggest that the soil particle size is the most important controller of SOC pools, and the stocks of SOC and TN are strongly effected by soil development processes in the permafrost regions of the eastern Qinghai-Tibetan Plateau.
Racial Disparities in Mortality Among Middle-Aged and Older Men: Does Marriage Matter?
Su, Dejun; Stimpson, Jim P; Wilson, Fernando A
2015-07-01
Based on longitudinal data from the Health and Retirement Study, this study assesses the importance of marital status in explaining racial disparities in all-cause mortality during an 18-year follow-up among White and African American men aged 51 to 61 years in 1992. Being married was associated with significant advantages in household income, health behaviors, and self-rated health. These advantages associated with marriage at baseline also got translated into better survival chance for married men during the 1992-2010 follow-up. Both marital selection and marital protection were relevant in explaining the mortality advantages associated with marriage. After adjusting for the effect of selected variables on premarital socioeconomic status and health, about 28% of the mortality gap between White and African American men in the Health and Retirement Study can be explained by the relatively low rates of marriage among African American men. Addressing the historically low rates of marriage among African Americans and their contributing factors becomes important for reducing racial disparities in men's mortality. © The Author(s) 2014.
Murphy, Stephen J; Audino, Livia D; Whitacre, James; Eck, Jenalle L; Wenzel, John W; Queenborough, Simon A; Comita, Liza S
2015-03-01
Patterns of diversity and community composition in forests are controlled by a combination of environmental factors, historical events, and stochastic or neutral mechanisms. Each of these processes has been linked to forest community assembly, but their combined contributions to alpha and beta-diversity in forests has not been well explored. Here we use variance partitioning to analyze approximately 40,000 individual trees of 49 species, collected within 137 ha of sampling area spread across a 900-ha temperate deciduous forest reserve in Pennsylvania to ask (1) To what extent is site-to-site variation in species richness and community composition of a temperate forest explained by measured environmental gradients and by spatial descriptors (used here to estimate dispersal-assembly or unmeasured, spatially structured processes)? (2) How does the incorporation of land-use history information increase the importance attributed to deterministic community assembly? and (3) How do the distributions and abundances of individual species within the community correlate with these factors? Environmental variables (i.e., topography, soils, and distance to stream), spatial descriptors (i.e., spatial eigenvectors derived from Cartesian coordinates), and land-use history variables (i.e., land-use type and intensity, forest age, and distance to road), explained about half of the variation in both species richness and community composition. Spatial descriptors explained the most variation, followed by measured environmental variables and then by land- use history. Individual species revealed variable responses to each of these sets of predictor variables. Several species were associated with stream habitats, and others were strictly delimited across opposing north- and south-facing slopes. Several species were also associated with areas that experienced recent (i.e., <100 years) human land-use impacts. These results indicate that deterministic factors, including environmental and land-use history variables, are important drivers of community response. The large amount of "unexplained" variation seen here (about 50%) is commonly observed in other such studies attempting to explain distribution and abundance patterns of plant communities. Determining whether such large fractions of unaccounted for variation are caused by a lack of sufficient data, or are an indication of stochastic features of forest communities globally, will remain an important challenge for ecologists in the future.
Niu, Yu Jie; Yang, Si Wei; Wang, Gui Zhen; Liu, Li; Du, Guo Zhen; Hua, Li Min
2017-12-01
The research selected the alpine meadow located in the northeastern margin of the Qinghai-Tibet Plateau to study the changes of vegetation community and soil properties under different grazing intensities, as well as the quantitative relation between the distribution patterns of plant species and the physical and chemical properties of soil. The results showed that the grazing caused the differentiation of the initial vegetation community with the dominant plants, Elymus nutans and Stipa grandis. In the plots with high and low grazing intensities, the dominant plants had changed to Kobresia humilis and Melissitus ruthenica, and E. nutans and Poa crymophila, respectively. With the increase of grazing intensity, the plant richness, importance value and biomass were significantly decreased. The sequence of plant species importance value in each plot against grazing intensity could be fitted by a logarithmic model. The number of required plant species was reduced while the importance value of the remaining plant species accounted for 50% of the importance value in the whole vegetation community. The available P, available K, soil compaction, soil water content, stable infiltration rate and large aggregate index were significantly changed with grazing intensity, however, the changes were different. The CCA ordination showed that the soil compaction was the key factor affecting the distribution pattern of the plant species under grazing. The variance decomposition indicated that the soil factors together explained 30.5% of the distribution of the plant species, in particular the soil physical properties alone explained 22.8% of the distribution of the plant species, which had the highest rate of contribution to the plant species distribution. The soil physical properties affected the distribution pattern of plant species on grazed alpine meadow.
Moor, Irene; Rathmann, Katharina; Stronks, Karien; Levin, Kate; Spallek, Jacob; Richter, Matthias
2014-10-01
The relative contribution of different pathways leading to health inequalities in adolescence was rarely investigated, especially in a cross-national perspective. The aim of the study is to analyse the contribution of psychosocial and behavioural factors in the explanation of inequalities in adolescent self-rated health (SRH) by family wealth in 28 countries. This study was based on the international WHO 'Health Behaviour in School-aged Children' (HBSC) study carried out in 2005/2006. The total sample included 117 460 adolescents aged 11-15 in 28 European and North American countries. Socioeconomic position was measured using the Family Affluence Scale (FAS). Multilevel logistic regression models were conducted to analyse the direct (independent) and indirect contribution of psychosocial and behavioural factors on SRH. Across all countries, adolescents from low affluent families had a higher risk of reporting fair/poor SRH (OR1.76, CI 1.69 to 1.84). Separate adjustments for psychosocial and behavioural factors reduced the OR of students with low family affluence by 39% (psychosocial) and 22% (behavioural). Together, both approaches explained about 50-60% of inequalities by family affluence in adolescent SRH. Separate analyses showed that relationship to father and academic achievement (psychosocial factors) as well as physical activity and consumption of fruits/vegetables (behavioural factors) were the most important factors in explaining inequalities in SRH. More than half of the inequalities by family affluence in adolescent SRH were explained by an unequal distribution of psychosocial and behavioural factors. Combining both approaches showed that the contribution of psychosocial factors was higher due to their direct (independent) and indirect impact through behavioural factors. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Schmid, L; Jankowiak, S; Kaluscha, R; Krischak, G
2016-06-01
The first step to initiate a stepwise occupational reintegration (SOR) is the recommendation of the rehabilitation centers. Therefore rehabilitation centers have a significant impact on the use of SOR. There is evidence that the recommendation rate between the rehabilitation centers differs clearly. The present survey therefore analyses in detail the differences of the recommendation rate and examines which patient-related factors could explain the differences. This study is based on analysis of routine data provided by the German pension insurance in Baden-Württemberg (Rehabilitationsstatistikdatenbasis 2013; RSD). In the analyses rehabilitation measures were included if they were conducted by employed patients (18-64 years) with a muscular-skeletal system disease or a disorder of the connective tissue. Logistic regression models were performed to explain the differences in the recommendation rate of the rehabilitation centers. The data of 134 853 rehabilitation measures out of 32 rehabilitation centers were available. The recommendation rate differed between the rehabilitation centers from 1.36-18.53%. The logistic regression analysis showed that the period of working incapacity 12 month before the rehabilitation and the working capacity on the current job were the most important predictors for the recommendation of a SOR by the rehabilitation centers. Also the rehabilitation centers themselves have an important influence. The results of this survey indicate that the characteristic of the patients is an important factor for the recommendation of SOR. Additionally the rehabilitation centers themselves have an influence on the recommendation of SOR. The results point to the fact that the rehabilitation centers use different criteria by making a recommendation. © Georg Thieme Verlag KG Stuttgart · New York.
Mehra, Lucky K; Cowger, Christina; Gross, Kevin; Ojiambo, Peter S
2016-01-01
Pre-planting factors have been associated with the late-season severity of Stagonospora nodorum blotch (SNB), caused by the fungal pathogen Parastagonospora nodorum, in winter wheat (Triticum aestivum). The relative importance of these factors in the risk of SNB has not been determined and this knowledge can facilitate disease management decisions prior to planting of the wheat crop. In this study, we examined the performance of multiple regression (MR) and three machine learning algorithms namely artificial neural networks, categorical and regression trees, and random forests (RF), in predicting the pre-planting risk of SNB in wheat. Pre-planting factors tested as potential predictor variables were cultivar resistance, latitude, longitude, previous crop, seeding rate, seed treatment, tillage type, and wheat residue. Disease severity assessed at the end of the growing season was used as the response variable. The models were developed using 431 disease cases (unique combinations of predictors) collected from 2012 to 2014 and these cases were randomly divided into training, validation, and test datasets. Models were evaluated based on the regression of observed against predicted severity values of SNB, sensitivity-specificity ROC analysis, and the Kappa statistic. A strong relationship was observed between late-season severity of SNB and specific pre-planting factors in which latitude, longitude, wheat residue, and cultivar resistance were the most important predictors. The MR model explained 33% of variability in the data, while machine learning models explained 47 to 79% of the total variability. Similarly, the MR model correctly classified 74% of the disease cases, while machine learning models correctly classified 81 to 83% of these cases. Results show that the RF algorithm, which explained 79% of the variability within the data, was the most accurate in predicting the risk of SNB, with an accuracy rate of 93%. The RF algorithm could allow early assessment of the risk of SNB, facilitating sound disease management decisions prior to planting of wheat.
High Spending on Maternity Care in India: What Are the Factors Explaining It?
Moradhvaj; Rammohan, Anu; Shruti; Pradhan, Jalandhar
2016-01-01
Background and Objectives High maternity-related health care spending is often cited as an important barrier in utilizing quality health care during pregnancy and childbirth. This study has two objectives: (i) to measure the levels of expenditure on total maternity care in disaggregated components such as ANCs, PNCs, and Natal care expenditure; (ii) to quantify the extent of catastrophic maternity expenditure (CME) incurred by households and identify the factors responsible for it. Methods and Findings Data from the 71st round of the National Sample Survey (2014) was used to estimate maternity expenditure and its predictors. CME was measured as a share of consumption expenditure by different cut-offs. The two-part model was used to identify the factors associated with maternity spending and CME. The findings show that household spending on maternity care (US$ 149 in constant price) is much higher than previous estimates (US$ 50 in constant price). A significant proportion of households in India (51%) are incurring CME. Along with economic and educational status, type of health care and place of residence emerged as significant factors in explaining CME. Conclusion Findings from this study assume importance in the context of an emerging demand for higher maternity entitlements and government spending on public health care in India. To reduce CME, India needs to improve the availability and accessibility of better-quality public health services and increase maternity entitlements in line with maternity expenditure identified in this study. PMID:27341520
Lagares, Alfonso; Jiménez-Roldán, Luis; Gomez, Pedro A; Munarriz, Pablo M; Castaño-León, Ana M; Cepeda, Santiago; Alén, José F
2015-12-01
Quantitative estimation of the hemorrhage volume associated with aneurysm rupture is a new tool of assessing prognosis. To determine the prognostic value of the quantitative estimation of the amount of bleeding after aneurysmal subarachnoid hemorrhage, as well the relative importance of this factor related to other prognostic indicators, and to establish a possible cut-off value of volume of bleeding related to poor outcome. A prospective cohort of 206 patients consecutively admitted with the diagnosis of aneurysmal subarachnoid hemorrhage to Hospital 12 de Octubre were included in the study. Subarachnoid, intraventricular, intracerebral, and total bleeding volumes were calculated using analytic software. For assessing factors related to prognosis, univariate and multivariate analysis (logistic regression) were performed. The relative importance of factors in determining prognosis was established by calculating their proportion of explained variation. Maximum Youden index was calculated to determine the optimal cut point for subarachnoid and total bleeding volume. Variables independently related to prognosis were clinical grade at admission, age, and the different bleeding volumes. The proportion of variance explained is higher for subarachnoid bleeding. The optimal cut point related to poor prognosis is a volume of 20 mL both for subarachnoid and total bleeding. Volumetric measurement of subarachnoid or total bleeding volume are both independent prognostic factors in patients with aneurysmal subarachnoid hemorrhage. A volume of more than 20 mL of blood in the initial noncontrast computed tomography is related to a clear increase in poor outcome risk. : aSAH, aneurysmal subarachnoid hemorrhage.
Food choice motives and the importance of family meals among immigrant mothers.
Marquis, Marie; Shatenstein, Bryna
2005-01-01
To determine the health and social benefits of the family mealtime, we examined the contribution of immigrant mothers' food motives to the importance placed on family meals, and cultural differences in mothers' food motives and the importance ascribed to family meals. Data were taken from a study on food choice factors among ten- to 12-year-old children from three cultural communities in Montreal. A 24-item, self-administered questionnaire was used to explore food choice motives. Each mother was also asked how important it was for her family to take the time to eat together, and if the child enjoyed sharing meals with his or her family. In all, 209 of the 653 questionnaires distributed were valid; 68 were from Haitian, 75 from Portuguese, and 66 from Vietnamese mothers. Five factors emerging from factor analyses explained 61.67% of the variance. Analysis of variance indicated significant differences between mothers' countries of origin for the importance placed on health, pleasure, familiarity, and ingredient properties (p<0.005). Among Haitian and Portuguese mothers, health motivations emerged as the only significant predictor of the importance given to family meals, whereas for Vietnamese mothers, both health and eating familiar foods were predictors (p<0.05).
The significance of the psychosocial factors influence in pathogenesis of cardiovascular disease.
Masic, Izet; Alajbegovic, Jasmin
2013-11-01
Cardiovascular diseases (CVD) are the leading cause of death in the world today. Risk factors are those factors that influence the development of CVD. Risk factors can be divided into materialistic (genetic predisposition, smoking, alcohol) and non-materialistic (psychosocial factors). Our goal is to note the role of the health system, to emphasize the importance of psychosocial factors in the pathogenesis of CVD, explain the relationship between psychosocial factors and other risk factors, stress the importance of prevention through the provision of management of the cardiovascular system (CVS) diseases. A DESCRIPTIVE ANALYSIS WAS PERFORMED ON SCIENTIFIC STUDIES IN SEVERAL PUBLISHED ARTICLES IN JOURNALS ON CVS: Public Health Reviews, CVD, European Heart Journal, Materia Socio Medica and other indexed journals that publish articles on CVS. THE IMPORTANCE AND ROLE OF THE HEALTH SYSTEM IN THE EARLY DETECTION, DIAGNOSIS, THERAPY AND CVS DISEASE PREVENTION IS PRESENTED THROUGH THREE THEMATIC AREAS: (a) The incidence and prevalence of CVS diseases; (b) treatment of CVS diseases and (c) promotion of health in patients with CVS disease and those the risk of their occurrence. Health promotion is the most important aspect of the health system monitoring. Health promotion is adequately implemented ifthe management ofCVD is proper. The main objectives of CVD management are: Preventing or delaying the occurrence of CVD, reducing the number and severity of worsening and complications of CVD. Management Includes: Individual and family, the health system and the community. Materialistic and non-materialistic risk factors together contribute to the development of CVD.
Knight, Louise; Nakuti, Janet; Allen, Elizabeth; Gannett, Katherine R.; Naker, Dipak; Devries, Karen M.
2016-01-01
Background The nature and structure of the school environment has the potential to shape children's health and well being. Few studies have explored the importance of school-level factors in explaining a child's likelihood of experiencing violence from school staff, particularly in low-resource settings such as Uganda. Methods To quantify to what extent a student's risk of violence is determined by school-level factors we fitted multilevel logistic regression models to investigate associations and present between-school variance partition coefficients. School structural factors, academic and supportive environment are explored. Results 53% of students reported physical violence from staff. Only 6% of variation in students' experience of violence was due to differences between schools and half the variation was explained by the school-level factors modelled. Schools with a higher proportion of girls are associated with increased odds of physical violence from staff. Students in schools with a high level of student perceptions of school connectedness have a 36% reduced odds of experiencing physical violence from staff, but no other school-level factor was significantly associated. Conclusion Our findings suggest that physical violence by school staff is widespread across different types of schools in this setting, but interventions that improve students' school connectedness should be considered. PMID:26647396
Determination of Dimensionless Attenuation Coefficient in Shaped Resonators
NASA Technical Reports Server (NTRS)
Daniels, C.; Steinetz, B.; Finkbeiner, J.; Raman, G.; Li, X.
2003-01-01
The value of dimensionless attenuation coefficient is an important factor when numerically predicting high-amplitude acoustic waves in shaped resonators. Both the magnitude of the pressure waveform and the quality factor rely heavily on this dimensionless parameter. Previous authors have stated the values used, but have not completely explained their methods. This work fully describes the methodology used to determine this important parameter. Over a range of frequencies encompassing the fundamental resonance, the pressure waves were experimentally measured at each end of the shaped resonators. At the corresponding dimensionless acceleration, the numerical code modeled the acoustic waveforms generated in the resonator using various dimensionless attenuation coefficients. The dimensionless attenuation coefficient that most closely matched the pressure amplitudes and quality factors of the experimental and numerical results was determined to be the value to be used in subsequent studies.
Chen, Yun; Niu, Shuai; Li, Peikun; Jia, Hongru; Wang, Hailiang; Ye, Yongzhong; Yuan, Zhiliang
2017-01-01
Elucidating the major drivers of bryophyte distribution is the first step to protecting bryophyte diversity. Topography, forest, substrates (ground, tree trunks, roots, rocks, and rotten wood), and spatial factor, which factors are the major drivers of bryophyte distribution? In this study, 53 plots were set in 400 m2 along the elevation gradient in Xiaoqinling, China. All bryophytes in the plots were collected and identified. Regression analysis was used to examine the relationship between bryophyte and substrate diversity. We compared the patterns of overall bryophyte diversity and diversity of bryophytes found on the ground, tree, and rock along elevational gradients. Canonical correspondence analysis was applied to relate species composition to selected environmental variables. The importance of topography, forest, substrates, and spatial factors was determined by variance partitioning. A total of 1378 bryophyte specimens were collected, and 240 species were identified. Bryophyte diversity was closely related to substrate diversity. The overall bryophyte diversity significantly increased with elevation; however, the response varied among ground, tree, and rock bryophytes. Tree diversity and herb layer were considered important environmental factors in determining bryophyte distribution. Species abundance was best explained by stand structure (17%), and species diversity was best explained by stand structure (35%) and substrate (40%). Results directly indicated that substrate diversity can improve bryophyte species diversity. The effects of micro-habitat formed by stand structure and substrate diversity were higher than those of spatial processes and topography factors on bryophyte distribution. This study proved that the determinant factors influencing bryophyte diversity reflect the trends in recent forest management, providing a real opportunity to improve forest biodiversity conservation. PMID:28603535
Chen, Yun; Niu, Shuai; Li, Peikun; Jia, Hongru; Wang, Hailiang; Ye, Yongzhong; Yuan, Zhiliang
2017-01-01
Elucidating the major drivers of bryophyte distribution is the first step to protecting bryophyte diversity. Topography, forest, substrates (ground, tree trunks, roots, rocks, and rotten wood), and spatial factor, which factors are the major drivers of bryophyte distribution? In this study, 53 plots were set in 400 m 2 along the elevation gradient in Xiaoqinling, China. All bryophytes in the plots were collected and identified. Regression analysis was used to examine the relationship between bryophyte and substrate diversity. We compared the patterns of overall bryophyte diversity and diversity of bryophytes found on the ground, tree, and rock along elevational gradients. Canonical correspondence analysis was applied to relate species composition to selected environmental variables. The importance of topography, forest, substrates, and spatial factors was determined by variance partitioning. A total of 1378 bryophyte specimens were collected, and 240 species were identified. Bryophyte diversity was closely related to substrate diversity. The overall bryophyte diversity significantly increased with elevation; however, the response varied among ground, tree, and rock bryophytes. Tree diversity and herb layer were considered important environmental factors in determining bryophyte distribution. Species abundance was best explained by stand structure (17%), and species diversity was best explained by stand structure (35%) and substrate (40%). Results directly indicated that substrate diversity can improve bryophyte species diversity. The effects of micro-habitat formed by stand structure and substrate diversity were higher than those of spatial processes and topography factors on bryophyte distribution. This study proved that the determinant factors influencing bryophyte diversity reflect the trends in recent forest management, providing a real opportunity to improve forest biodiversity conservation.
Predictive factors of telemedicine service acceptance and behavioral intention of physicians.
Rho, Mi Jung; Choi, In Young; Lee, Jaebeom
2014-08-01
Despite the proliferation of telemedicine technology, telemedicine service acceptance has been slow in actual healthcare settings. The purpose of this research is to develop a theoretical model for explaining the predictive factors influencing physicians' willingness to use telemedicine technology to provide healthcare services. We developed the Telemedicine Service Acceptance model based on the technology acceptance model (TAM) with the inclusion of three predictive constructs from the previously published telemedicine literature: (1) accessibility of medical records and of patients as clinical factors, (2) self-efficacy as an individual factor and (3) perceived incentives as regulatory factors. A survey was conducted, and structural equation modeling was applied to evaluate the empirical validity of the model and causal relationships within the model using the data collected from 183 physicians. Our results confirmed the validity of the original TAM constructs: the perceived usefulness of telemedicine directly impacted the behavioral intention to use it, and the perceived ease of use directly impacted both the perceived usefulness and the behavioral intention to use it. In addition, new predictive constructs were found to have ramifications on TAM variables: the accessibility of medical records and of patients directly impacted the perceived usefulness of telemedicine, self-efficacy had a significant positive effect on both the perceived ease of use and the perceived usefulness of telemedicine, and perceived incentives were found to be important with respect to the intention to use telemedicine technology. This study demonstrated that the Telemedicine Service Acceptance model was feasible and could explain the acceptance of telemedicine services by physicians. These results identified important factors for increasing the involvement of physicians in telemedicine practice. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Nero, Håkan; Benka Wallén, Martin; Franzén, Erika; Conradsson, David; Ståhle, Agneta; Hagströmer, Maria
2016-10-19
The desirable effects of physical activity in individuals with Parkinson's disease are well-known, although according to results from previous studies factors associated with objectively assessed physical activity are not fully investigated. To investigate demographic, disease-related and mobility-related factors that associate with objectively measured physical activity, in a sample of older adults with mild to moderate Parkinson's disease. Demographic, disease-related and mobility-related factors were gathered by interview from a total of 91 older adults with Parkinson's disease, followed by an evaluation of balance control using the Mini-BESTest. After initial testing, participants wore a tri-axial accelerometer during a week of free-living. Correlation analysis and multiple linear regression was used to investigate factors associated with total PA, represented by total activity counts, and time in brisk walking. Motor impairment, physical function, body mass index and dyskinesia contributed to the variance of total physical activity, explaining 34 % of the variance, while physical function and balance control were significant factors associated with brisk walking, explaining 22 %. This study identified factors that have not been shown to associate with objectively measured physical activity previously, such as dyskinesia, balance control and self-rated physical function. The findings also demonstrated that associated factors differ, depending on the activity behavior being investigated. However, other factors than those included in this study may also be of importance.
Aerodynamic drag crisis and its possible effect on the flight of baseballs
NASA Astrophysics Data System (ADS)
Frohlich, Cliff
1984-04-01
At Reynolds numbers above about 105 the aerodynamic drag force on a sphere drops sharply as the flow begins to become turbulent in the boundary layer. For baseballs, this ``drag crisis'' may occur at speeds which are typical for pitched or batted balls. The effects of the drag reduction on the behavior of both pitched and batted balls is significant, and may explain several features of the game of baseball which previously have been unexplained or attributed to other causes. In particular, the drag reduction may help to explain why pitched fastballs appear to rise, why pitched curve balls appear to drop sharply, and why home run production has increased since the introduction of the alleged ``lively ball.'' Calculations suggest that aerodynamic forces are as important a factor in fastpitch softball as in baseball, and that they are a critical factor in a number of other ball games.
Explaining the Widening Education Gap in Mortality among U.S. White Women
Montez, Jennifer Karas; Zajacova, Anna
2013-01-01
Over the last half century the gap in mortality across education levels grew in the United States, and since the mid-1980s the growth was especially pronounced among white women. The reasons for the growth among white women are unclear. We investigated three explanations—social-psychological factors, economic circumstances, and health behaviors—for the widening education gap in mortality across 1997-2006 among white women 45-84 years of age. We used data from the National Health Interview Survey Linked Mortality File (N=46,744; deaths=4,053). We found little support for social-psychological factors; however, economic circumstances and health behaviors jointly explained the growing education gap in mortality to statistical nonsignificance. Employment and smoking were the most important individual components. Increasing high school graduation rates, reducing smoking prevalence, and designing work-family policies that help women find and maintain desirable employment may reduce mortality inequalities among women. PMID:23723344
Explaining the widening education gap in mortality among U.S. white women.
Montez, Jennifer Karas; Zajacova, Anna
2013-06-01
Over the past half century the gap in mortality across education levels has grown in the United States, and since the mid-1980s, the growth has been especially pronounced among white women. The reasons for the growth among white women are unclear. We investigated three explanations-social-psychological factors, economic circumstances, and health behaviors-for the widening education gap in mortality from 1997 to 2006 among white women aged 45 to 84 years using data from the National Health Interview Survey Linked Mortality File (N = 46,744; 4,053 deaths). Little support was found for social-psychological factors, but economic circumstances and health behaviors jointly explained the growing education gap in mortality to statistical nonsignificance. Employment and smoking were the most important individual components. Increasing high school graduation rates, reducing smoking prevalence, and designing work-family policies that help women find and maintain desirable employment may reduce mortality inequalities among women.
Bērziņa, Guna; Smilškalne, Baiba; Vētra, Anita; Sunnerhagen, Katharina S
2016-06-24
To investigate how functional, social and personal factors are associated with self-perceived level of disability in the chronic phase of stroke in a Latvian stroke population. The consequences of stroke can vary greatly and often leads to long-term disability that, according to the WHO definitions, depends on the interaction between the person and his/her context. Cross-sectional study with retrospective data gathering. Community-dwelling persons who received specialised in-patient rehabilitation after stroke in Latvia. Of 600 persons after stroke who were identified through hospital register and selected for the study, 255 were included in the analysis. The medical information and discharge data of the Functional Independence Measure (FIM) was extracted from medical records. Participants filled out a questionnaire on sociodemographic information and the WHO Disability Assessment Schedule 2.0 (WHODAS 2.0), either in Latvian or Russian, depending on their wish when contacted for their oral agreement to participate. Stepwise multiple regression analysis was conducted to find a model that best explains the variance in WHODAS 2.0 scores. The models explained 23-43.5% of variance in outcomes. The best explained WHODAS 2.0 domains were 'mobility' and 'self-care'. The significant factors were level of independence in 'self-care', 'locomotion' and 'communication' according to FIM, as well as working status, time since rehabilitation, age, gender, living alone or in family and preferred language. Functional, social and personal factors are of similar importance when explaining self-perceived disability in the chronic phase of stroke. Some, but not all, of the factors are modifiable by the healthcare system. Therefore, a complex approach and involvement of medical, social and political systems is needed. 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/
Rodenacker, Klaas; Hautmann, Christopher; Görtz-Dorten, Anja; Döpfner, Manfred
2018-05-01
The trait-impulsivity etiological model assumes that a general factor (trait-impulsivity) underlies attention-deficit/hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), and other externalizing disorders. We investigated the plausibility of this assumption by testing the factor structure of ADHD and ODD in a bifactor framework for a clinical sample of 1420 children between 6 and 18 years of age (M = 9.99, SD = 3.34; 85% male). Further, the trait-impulsivity etiological model assumes that ODD emerges only if environmental risk factors are present. Our results support the validity of the trait-impulsivity etiological model, as they confirm that ADHD and ODD share a strong general factor of disruptive behavior (DB) in this clinical sample. Furthermore, unlike the subdimensions of ADHD, we found that the specific ODD factor explained as much true score variance as the general DB factor. This suggests that a common scale of ADHD and ODD may prove to be as important as a separate ODD subscale to assess externalizing problems in school-age children. However, all other subscales of ADHD may not explain sufficient true score variance once the impact of the general DB factor has been taken into consideration. In accordance with the trait-impulsivity model, we also showed that all factors, but predominantly the general factor and specific inattention factor, predicted parent-rated impairment, and that predominantly ODD and impulsivity are predicted by environmental risk factors.
Class and ideological orientations revisited: an exploration of class-based mechanisms.
Bengtsson, Mattias; Berglund, Tomas; Oskarson, Maria
2013-12-01
Studies of the relationship between class position and political outlooks still only have a limited understanding of the class-related mechanisms that matter for ideological orientations. This article presents a comprehensive analysis of the mechanisms that link class position and left/right and authoritarian/libertarian orientations. Besides main factors such as income, career prospects, job security, education, class origin and class identification, the significance of work-related factors such as work autonomy, working in a team, a physically demanding job and a mentally demanding job is studied. The findings are based on a survey specifically designed for this purpose and collected in Sweden in 2008/2009. A great deal of the association between class position and left/right orientations is explained by socio-economic conditions; different classes sympathize with policies that will benefit them economically. Another important factor is class identification. Work-related factors also have relevance, but the effect of class position on left/right orientations works mainly through the remuneration system. Class position is also related to authoritarian/libertarian orientations. However, this relationship is less explained by socio-economic position per se, but is rather an effect of the educational system and its allocation of the workforce into different class positions. It also turns out that work-related factors do not explain the class effects; however, a physically demanding job shows a unique effect. Overall, our findings suggest that besides factors such as class position, income, education and class identification, we need to consider work-related aspects to derive a more complete understanding of the distribution of ideological orientations in Western societies. © London School of Economics and Political Science 2013.
Endpoint Model of Exclusive Processes
NASA Astrophysics Data System (ADS)
Dagaonkar, Sumeet; Jain, Pankaj; Ralston, John P.
2018-07-01
The endpoint model explains the scaling laws observed in exclusive hadronic reactions at large momentum transfer in all experimentally important regimes. The model, originally conceived by Feynman and others, assumes a single valence quark carries most of the hadron momentum. The quark wave function is directly related to the momentum transfer dependence of the reaction. After extracting the momentum dependence of the quark wave function from one process, it explains all the others. Endpoint quark-counting rules relate the number of quarks in a hadron to the power-law. A universal linear endpoint behavior explains the proton electromagnetic form factors F1 and F2, proton-proton scattering at fixed-angle, the t-dependence of proton-proton scattering at large s>> t, and Compton scattering at fixed t. The model appears to be the only comprehensive mechanism consistent with all experimental information.
Critical Factors Explaining the Leadership Performance of High-Performing Principals
ERIC Educational Resources Information Center
Hutton, Disraeli M.
2018-01-01
The study explored critical factors that explain leadership performance of high-performing principals and examined the relationship between these factors based on the ratings of school constituents in the public school system. The principal component analysis with the use of Varimax Rotation revealed that four components explain 51.1% of the…
Crosstalk between ERK2 and RXR regulates nuclear import of transcription factor NGFI-B
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jacobs, Chris M.; Paulsen, Ragnhild E.
2005-10-21
Transcription factor NGFI-B initiates apoptosis when allowed to translocate to mitochondria. Retinoid-X receptor (RXR), another member of the nuclear receptor family, regulates NGFI-B signaling through heterodimerization and nuclear export. Growth factor EGF activates ERK2, which phosphorylates NGFI-B and determines if NGFI-B is allowed to translocate to mitochondria. In the present study, EGF treatment resulted in an increased nuclear import of NGFI-B. Likewise, active ERK2 resulted in a preferential nuclear localization of NGFI-B. When coexpressed with RXR the nuclear import and nuclear localization induced by active ERK2 were strongly reduced. In the presence of its ligand 9-cis-retinoic acid, RXR no longermore » inhibited ERK2-induced nuclear import. Thus, RXR serves a permissive role for ERK2-mediated nuclear accumulation of NGFI-B. This finding represents a novel crosstalk between ERK2 and RXR signaling pathways, and explains how two independent inhibitors of apoptosis (EGF and 9-cis-retinoic acid) may cooperate to regulate nuclear targeting of apoptosis inducer NGFI-B.« less
ERIC Educational Resources Information Center
Bonjar, Abdolreza Bagheri
2017-01-01
Delinquency is a social phenomenon and has social context though biological factors, psychological, geographical, ethnic, racial and other items in the forming and occurring type of delinquency play an important role, explain the issue is on the basis of the social environment, limiting attitude of sociology scope in particular, the performance of…
ERIC Educational Resources Information Center
Wilcox, Gabrielle; McQuay, Jocelyn; Blackstaffe, Anita; Perry, Rosemary; Hawe, Penelope
2016-01-01
Understanding what contributes to academic engagement is important to effectively support students. This study examines the relationship between sociodemographic factors, anxiety, social support, and academic engagement in elementary and junior high school students. Students in grades 5-9 (N = 1,904) completed self-reports measuring academic…
Labor Force Participation and Poverty Status among Rural and Urban Women Who Head Families.
ERIC Educational Resources Information Center
Cautley, Eleanor; Slesinger, Doris P.
1988-01-01
Urban women are better off in labor force participation and poverty than women in central city and rural areas. Differences in access to jobs and welfare benefits explain the urban-rural variation. Finds that the most important factor for not living in poverty is earning income. Recommends policies for reducing poverty among single, working…
ERIC Educational Resources Information Center
Bailey, Thomas; Calcagno, Juan Carlos; Jenkins, Davis; Leinbach, Timothy; Kienzl, Gregory
2005-01-01
Policymakers, educators, and researchers recognize the importance of community colleges as open door institutions that provide a wide range of students with access to college. At the same time, competing demands for the state funds that would support community colleges have resulted in reduced public allocations and higher student tuition fees.…
Black, R.W.; Moran, P.W.; Frankforter, J.D.
2011-01-01
Many streams within the United States are impaired due to nutrient enrichment, particularly in agricultural settings. The present study examines the response of benthic algal communities in agricultural and minimally disturbed sites from across the western United States to a suite of environmental factors, including nutrients, collected at multiple scales. The first objective was to identify the relative importance of nutrients, habitat and watershed features, and macroinvertebrate trophic structure to explain algal metrics derived from deposition and erosion habitats. The second objective was to determine if thresholds in total nitrogen (TN) and total phosphorus (TP) related to algal metrics could be identified and how these thresholds varied across metrics and habitats. Nutrient concentrations within the agricultural areas were elevated and greater than published threshold values. All algal metrics examined responded to nutrients as hypothesized. Although nutrients typically were the most important variables in explaining the variation in each of the algal metrics, environmental factors operating at multiple scales also were important. Calculated thresholds for TN or TP based on the algal metrics generated from samples collected from erosion and deposition habitats were not significantly different. Little variability in threshold values for each metric for TN and TP was observed. The consistency of the threshold values measured across multiple metrics and habitats suggest that the thresholds identified in this study are ecologically relevant. Additional work to characterize the relationship between algal metrics, physical and chemical features, and nuisance algal growth would be of benefit to the development of nutrient thresholds and criteria. ?? 2010 The Author(s).
Liebezeit, Joseph R.; Gurney, K. E. B.; Budde, Michael E.; Zack, Steve; Ward, David H.
2014-01-01
Previous studies have documented advancement in clutch initiation dates (CIDs) in response to climate change, most notably for temperate-breeding passerines. Despite accelerated climate change in the Arctic, few studies have examined nest phenology shifts in arctic breeding species. We investigated whether CIDs have advanced for the most abundant breeding shorebird and passerine species at a long-term monitoring site in arctic Alaska. We pooled data from three additional nearby sites to determine the explanatory power of snow melt and ecological variables (predator abundance, green-up) on changes in breeding phenology. As predicted, all species (semipalmated sandpiper, Calidris pusilla, pectoral sandpiper, Calidris melanotos, red-necked phalarope, Phalaropus lobatus, red phalarope, Phalaropus fulicarius, Lapland longspur, Calcarius lapponicus) exhibited advanced CIDs ranging from 0.40 to 0.80 days/year over 9 years. Timing of snow melt was the most important variable in explaining clutch initiation advancement (“climate/snow hypothesis”) for four of the five species, while green-up was a much less important explanatory factor. We found no evidence that high predator abundances led to earlier laying dates (“predator/re-nest hypothesis”). Our results support previous arctic studies in that climate change in the cryosphere will have a strong impact on nesting phenology although factors explaining changes in nest phenology are not necessarily uniform across the entire Arctic. Our results suggest some arctic-breeding shorebird and passerine species are altering their breeding phenology to initiate nesting earlier enabling them to, at least temporarily, avoid the negative consequences of a trophic mismatch.
Black, Robert W; Moran, Patrick W; Frankforter, Jill D
2011-04-01
Many streams within the United States are impaired due to nutrient enrichment, particularly in agricultural settings. The present study examines the response of benthic algal communities in agricultural and minimally disturbed sites from across the western United States to a suite of environmental factors, including nutrients, collected at multiple scales. The first objective was to identify the relative importance of nutrients, habitat and watershed features, and macroinvertebrate trophic structure to explain algal metrics derived from deposition and erosion habitats. The second objective was to determine if thresholds in total nitrogen (TN) and total phosphorus (TP) related to algal metrics could be identified and how these thresholds varied across metrics and habitats. Nutrient concentrations within the agricultural areas were elevated and greater than published threshold values. All algal metrics examined responded to nutrients as hypothesized. Although nutrients typically were the most important variables in explaining the variation in each of the algal metrics, environmental factors operating at multiple scales also were important. Calculated thresholds for TN or TP based on the algal metrics generated from samples collected from erosion and deposition habitats were not significantly different. Little variability in threshold values for each metric for TN and TP was observed. The consistency of the threshold values measured across multiple metrics and habitats suggest that the thresholds identified in this study are ecologically relevant. Additional work to characterize the relationship between algal metrics, physical and chemical features, and nuisance algal growth would be of benefit to the development of nutrient thresholds and criteria.
NASA Astrophysics Data System (ADS)
Fischer, Christine; Hohenbrink, Tobias; Leimer, Sophia; Roscher, Christiane; Ravenek, Janneke; de Kroon, Hans; Kreutziger, Yvonne; Wirth, Christian; Eisenhauer, Nico; Gleixner, Gerd; Weigelt, Alexandra; Mommer, Liesje; Beßler, Holger; Schröder, Boris; Hildebrandt, Anke
2015-04-01
Soil moisture is the dynamic link between climate, soil and vegetation and the dynamics and variation are affected by several often interrelated factors such as soil texture, soil structural parameters (soil organic carbon) and vegetation parameters (belowground- and aboveground biomass). For the characterization and estimation of soil moisture and its variability and the resulting water fluxes and solute transports, the knowledge of the relative importance of these factors is of major challenge for hydrology and bioclimatology. Because of the heterogeneity of these factors, soil moisture varies strongly over time and space. Our objective was to assess the spatio-temporal variability of soil moisture and factors which could explain that variability, like soil properties and vegetation cover, in in a long term biodiversity experiment (Jena Experiment). The Jena Experiment consist 86 plots on which plant species richness (0, 1, 2, 4, 8, 16, and 60) and functional groups (legumes, grasses, tall herbs, and small herbs) were manipulated in a factorial design Soil moisture measurements were performed weekly April to September 2003-2005 and 2008-2013 using Delta T theta probe. Measurements were integrated to three depth intervals: 0.0 - 0.20, 0.20 - 0.40 and 0.40 - 0.70 m. We analyze the spatio-temporal patterns of soil water content on (i) the normalized time series and (ii) the first components obtained from a principal component analysis (PCA). Both were correlated with the design variables of the Jena Experiment (plant species richness and plant functional groups) and other influencing factors such as soil texture, soil structural variables and vegetation parameters. For the time stability of soil water content, the analysis showed that plots containing grasses was consistently drier than average at the soil surface in all observed years while plots containing legumes comparatively moister, but only up to the year 2008. In 0.40 - 0.70 m soil deep plots presence of small herbs led to higher than average soil moisture in some years (2008, 2012, 2013). Interestingly, plant species richness led to moister than average subsoil at the beginning of the experiment (2003 and 2004), which changed to lower than average up to the year 2010 in all depths. There was no effect of species diversity in the years since 2010, although species diversity generally increases leaf area index and aboveground biomass. The first component from the PCA analysis described the mean behavior in time of all soil moisture time series. The second component reflected the impact of soil depth. The first two components explained 76% of the data set total variance. The third component is linked to plant species richness and explained about 4 % of the total variance of soil moisture data. The fourth component, which explained 2.4 %, showed a high correlation to soil texture. Within this study we investigate the dominant factors controlling spatio-temporal patterns of soil moisture at several soil depths. Although climate and soil depths were the most important drivers, other factors like plant species richness and soil texture affected the temporal variation while certain plant functional groups were important for the spatial variability.
Systems effects on family planning innovativeness.
Lee, S B
1983-12-01
Data from Korea were used to explore the importance of community level variables in explaining family planning adoption at the individual level. An open system concept was applied, assuming that individual family planning behavior is influenced by both environmental and individual factors. The environmental factors were measured at the village level and designated as community characteristics. The dimension of communication network variables was introduced. Each individual was characterized in terms of the degree of her involvement in family planning communication with others in her village. It was assumed that the nature of the communication network linking individuals with each other effects family planning adoption at the individual level. Specific objectives were to determine 1) the relative importance of the specific independent variables in explaining family planning adoption and 2) the relative importance of the community level variables in comparison with the individual level variables in explaining family planning adoption at the individual level. The data were originally gathered in a 1973 research project on Korea's mothers' clubs. 1047 respondents were interviewed, comprising all married women in 25 sample villages having mothers' clubs. The dependent variable was family planning adoption behavior, defined as current use of any of the modern methods of family planning. The independent variables were defined at 3 levels: individual, community, and at a level intermediate between them involving communication links between individuals. More of the individual level independent variables were significantly correlated with the dependent variables than the community level variables. Among those variables with statistically significant correlations, the correlation coefficients were consistently higher for the individual level than for the community level variables. More of the variance in the dependent variable was explained by individual level than by community level variables. Community level variables accounted for only about 2.5% of the total variance in the dependent variable, in marked contrast to the result showing individual level variables accounting for as much as 19% of the total variance. When both individual and community level variables were entered into a multiple correlation analysis, a multiple correlation coefficient of .4714 was obtained together they explained about 20% of the total variance. The 2 communication network variables--connectedness and integrativeness--were correlated with the dependent variable at much higher levels than most of the individual or community level variables. Connectedness accounted for the greatest amount of the total variance. The communication network variables as a group explained as much of the total variance in the dependent variable as the individual level variables and greatly more that the community level variables.
Environmental factors affecting feed intake of steers in different housing systems in the summer
NASA Astrophysics Data System (ADS)
Koknaroglu, H.; Otles, Z.; Mader, T.; Hoffman, M. P.
2008-07-01
A total of 188 yearling steers of predominantly Angus and Hereford breeds, with mean body weight of 299 kg, were used in this study, which started on 8 April and finished on 3 October, to assess the effects of environmental factors on feed intake of steers in various housing systems. Housing consisted of outside lots with access to overhead shelter, outside lots with no overhead shelter and a cold confinement building. Ad libitum corn, 2.27 kg of 35% dry matter whole plant sorghum silage and 0.68 kg of a 61% protein-vitamin-mineral supplement was offered. Feed that was not consumed was measured to determine feed intake. The temperature data were recorded by hygro-thermographs. Hourly temperatures and humidity were used to develop weather variables. Regression analysis was used and weather variables were regressed on dry matter intake (DMI). When addition of a new variable did not improve R 2 more than one unit, then the number of variables in the model was truncated. Cattle in confinement had lower DMI than those in open lots and those in open lots with access to an overhead shelter ( P < 0.05). Cattle in outside lots with access to overhead shelter had similar DMI compared to those in open lots ( P = 0.065). Effect of heat was predominantly displayed in August in the three housing systems. In terms of explaining variation in DMI, in outside lots with access to overhead shelter, average and daytime temperatures were important factors, whereas in open lots, nocturnal, peak and average temperatures were important factors. In confinement buildings, the previous day’s temperature and humidity index were the most important factors explaining variation in DMI. Results show the effect of housing and weather variables on DMI in summer and when considering these results, cattle producers wishing to improve cattle feedlot performance should consider housing conditions providing less stress or more comfort.
Placing and preserving priorities: projects, productivity, progress and people
Babiak, John
1998-01-01
High throughput screening (HTS) involves using automated equipment to test a large number of samples against a defined molecular target to identify a reasonable number of active molecules in a timely fashion. Major factors which can influence priorities for the limited resources of the HTS group are projects, productivity, progress and people. The challenge to the HTS group is to provide excellent and timely screening services, but still devote efforts to new technologies and personnel development. This article explains why these factors are so important. PMID:18924829
Dramatic response to inhaled dobesilate in a patient with lung squamous cell cancer
Cuevas, Pedro; Sueiro, Antonio; Navío, Pilar; Giménez-Gallego, Guillermo
2012-01-01
The effectiveness of local application, by inhalation, of dobesilate, an inhibitor of fibroblast growth factor signalling, in a patient with squamous cell lung carcinoma is reported. To our knowledge, these are the first published data on the efficacy of dobesilate in the treatment of this disease. The antimitotic, antiangiogenic, proapoptotic and anti-inflammatory activities of dobesilate can be important factors to consider, in explaining the efficacy of the treatment. Dobesilate administration can be a therapeutic option in patients with lung cancer having poor performance status or severe complications. PMID:22952275
Crisis of Meaning Predicts Suicidality in Youth Independently of Depression.
Schnell, Tatjana; Gerstner, Rebekka; Krampe, Henning
2018-02-23
At times, the question for meaning comes to nothing and a crisis of meaning ensues. This state is very painful, but difficult to account. Both those who suffer from it and care professionals find themselves at a loss for words. This study introduces an operationalization of a crisis of meaning. It aims to distinguish the concept from depression, and to investigate whether a crisis of meaning can explain suicidality beyond the known protective and risk factors self-esteem, family functioning, life-event load, and depression. Final-year school pupils in Ecuador (N = 300) completed questionnaires assessing the above variables. Data were analyzed using chi-square, hierarchic multiple regression, serial mediation, and moderator analyses. Crisis of meaning was distinguished from depression. It explained a significant amount of variance in suicidality beyond the mentioned protective and risk factors. For males, crisis of meaning was the only significant risk factor, and the strongest predictor overall. The acute risk factors depression and crisis of meaning mediated the effects of the baseline factors self-esteem, family functioning, and life-event load on suicidality. The study was cross-sectional; assessed factors predicted variance in suicidal thoughts, plans, and past suicide attempts, while their relevance cannot be generalized to actual future suicide attempts. A crisis of meaning is an important factor to take into account in further research on the prevention and treatment of people at risk of suicide.
NASA Astrophysics Data System (ADS)
Horak, Jakub; Hui, Cang; Roura-Pascual, Núria; Romportl, Dusan
2013-04-01
Regardless of their ecosystem functions, some insects are threatened when facing environmental changes and disturbances, while others become extremely successful. It is crucial for successful conservation to differentiate factors supporting species' current distributions from those triggering range dynamics. Here, we studied the sudden extralimital colonization of the rose chafer beetle, Oxythyrea funesta, in the Czech Republic. Specifically, we depicted the range expansion using accumulated historical records of first known occurrences and then explained the colonization events using five transformed indices depicting changes in local propagule pressure (LPP), climate, land use, elevation, and landscape structure. The slow occupancy increase of O. funesta before 1990 changed to a phase of rapid occupancy increase after 1990, driven not only by changes in the environment (climate and land use) but also by the spatial accumulation of LPP. Climate was also found to play a significant role but only during the niche-filling stage before 1990, while land use became important during the phase of rapid expansion after 1990. Inland waters (e.g., riparian corridors) also contributed substantially to the spread in the Czech Republic. Our method of using spatially transformed variables to explain the colonization events provides a novel way of detecting factors triggering range dynamics. The results highlight the importance of LPP in driving sudden occupancy increase of extralimital species and recommend the use of LPP as an important predictor for modeling range dynamics.
Social anxiety following traumatic brain injury: an exploration of associated factors.
Curvis, William; Simpson, Jane; Hampson, Natalie
2018-06-01
Social anxiety (SA) following traumatic brain injury (TBI) has the potential to affect an individual's general psychological well-being and social functioning, however little research has explored factors associated with its development. The present study used hierarchical multiple regression to investigate the demographic, clinical and psychological factors associated with SA following TBI. A sample of 85 people who experienced TBI were recruited through social media websites and brain injury services across the North-West of England. The overall combined biopsychosocial model was significant, explaining 52-54.3% of the variance in SA (across five imputations of missing data). The addition of psychological variables (self-esteem, locus of control, self-efficacy) made a significant contribution to the overall model, accounting for an additional 12.2-13% of variance in SA above that explained by demographic and clinical variables. Perceived stigma was the only significant independent predictor of SA (B = .274, p = .005). The findings suggest that psychological variables are important in the development of SA following TBI and must be considered alongside clinical factors. Furthermore, the significant role of stigma highlights the need for intervention at both an individualised and societal level.
Buzz Factor or Innovation Potential: What Explains Cryptocurrencies' Returns?
Wang, Sha; Vergne, Jean-Philippe
2017-01-01
Cryptocurrencies have become increasingly popular since the introduction of bitcoin in 2009. In this paper, we identify factors associated with variations in cryptocurrencies' market values. In the past, researchers argued that the "buzz" surrounding cryptocurrencies in online media explained their price variations. But this observation obfuscates the notion that cryptocurrencies, unlike fiat currencies, are technologies entailing a true innovation potential. By using, for the first time, a unique measure of innovation potential, we find that the latter is in fact the most important factor associated with increases in cryptocurrency returns. By contrast, we find that the buzz surrounding cryptocurrencies is negatively associated with returns after controlling for a variety of factors, such as supply growth and liquidity. Also interesting is our finding that a cryptocurrency's association with fraudulent activity is not negatively associated with weekly returns-a result that further qualifies the media's influence on cryptocurrencies. Finally, we find that an increase in supply is positively associated with weekly returns. Taken together, our findings show that cryptocurrencies do not behave like traditional currencies or commodities-unlike what most prior research has assumed-and depict an industry that is much more mature, and much less speculative, than has been implied by previous accounts.
Predictors of health-related quality of life in people with amyotrophic lateral sclerosis.
Sandstedt, Petter; Johansson, Sverker; Ytterberg, Charlotte; Ingre, Caroline; Holmqvist, Lotta Widén; Kierkegaard, Marie
2016-11-15
Knowledge of factors influencing health-related quality of life (HRQL) in people with amyotrophic lateral sclerosis (ALS) is important because some factors might be amenable to intervention. The aim was to describe and explore the effects of disease severity, fatigue, anxiety, depression, frequency of social and lifestyle activities, coping capacity and mechanical ventilator use on HRQL in people with ALS. Sixty people with ALS were enrolled in this cross-sectional study. Data were collected with questionnaires during home visits. The Sickness Impact Profile and the EuroQol Visual Analogue Scale were used to assess HRQL. Multivariate regression analyses explored associations between HRQL and independent factors. Low frequency of social and lifestyle activities, and severe disease, were associated with worse HRQL, explaining 57% of total variance in the Sickness Impact Profile physical score. Severe disease, weak coping capacity and anxiety and/or depression were associated with worse HRQL, explaining 33% of total variance in Sickness Impact Profile psychosocial score. Fatigue and mechanical ventilator use were associated with worse HRQL, explaining 17% of variance in the EuroQol Visual Analogue Scale. Knowledge and understanding of how frequency of social and lifestyle activities, disease severity, coping capacity, anxiety and/or depression, fatigue and ventilator use contribute to and predict self-rated HRQL can optimize person-centred care and support. Copyright © 2016 Elsevier B.V. All rights reserved.
Chouchane, Hatem; Krol, Maarten S; Hoekstra, Arjen Y
2018-02-01
Growing water demands put increasing pressure on local water resources, especially in water-short countries. Virtual water trade can play a key role in filling the gap between local demand and supply of water-intensive commodities. This study aims to analyse the dynamics in virtual water trade of Tunisia in relation to environmental and socio-economic factors such as GDP, irrigated land, precipitation, population and water scarcity. The water footprint of crop production is estimated using AquaCrop for six crops over the period 1981-2010. Net virtual water import (NVWI) is quantified at yearly basis. Regression models are used to investigate dynamics in NVWI in relation to the selected factors. The results show that NVWI during the study period for the selected crops is not influenced by blue water scarcity. NVWI correlates in two alternative models to either population and precipitation (model I) or to GDP and irrigated area (model II). The models are better in explaining NVWI of staple crops (wheat, barley, potatoes) than NVWI of cash crops (dates, olives, tomatoes). Using model I, we are able to explain both trends and inter-annual variability for rain-fed crops. Model II performs better for irrigated crops and is able to explain trends significantly; no significant relation is found, however, with variables hypothesized to represent inter-annual variability. Copyright © 2017 Elsevier B.V. All rights reserved.
Cortese, C G; Ghislieri, Chiara; Colombo, Lara
2008-01-01
Organization research has shown increasing interest in the dynamics of work-family conflict (w.f.c.). The NEXT study highlights that w.f.c. significantly influences satisfaction for one's job and the decision to quit the nursing profession. This study analyzes w.f.c. in a sample of Italian nurses, with the aim of examining the main differences in relation to personal variables, and understanding the degree to which w.f.c. explains job satisfaction. A self-reporting questionnaire was administered to 325 nurses in different hospitals of Northern Italy. Descriptive, reliability and Anova data analysis was performed. The relationships between variables were analyzed through correlations (Pearson's r); the role of w.f.c. in explaining job satisfaction was estimated via multiple regression. W.f.c. appeared to be more critical in subjects who had care responsibilities and in those who had more demanding work assignments. W.f.c. contributed to explaining job satisfaction, even if it was not its principal determining factor. This area of research appears to be important in that it leads to a better comprehension of the dynamics involved in work satisfaction and can suggest possible initiatives for support and development.
Leritz, Elizabeth C; McGlinchey, Regina E; Salat, David H; Milberg, William P
2016-04-01
We examined how serum cholesterol, an established risk factor for cerebrovascular disease (CVD), relates to cognitive function in healthy middle-older aged individuals with no neurologic or CVD history. A complete lipid panel was obtained from a cohort of one hundred twenty individuals, ages 43-85, who also underwent a comprehensive neuropsychological examination. In order to reduce the number of variables and empirically identify broad cognitive domains, scores from neuropsychological tests were submitted into a factor analysis. This analysis revealed three explainable factors: Memory, Executive Function and Memory/Language. Three separate hierarchical multiple regression analyses were conducted using individual cholesterol metrics (total cholesterol, low density lipoprotein; LDL, high density lipoprotein; HDL, and triglycerides), as well as age, education, medication status (lipid lowering agents), ApoE status, and additional risk factors for CVD to predict neuropsychological function. The Memory Factor was predicted by a combination of age, LDL, and triglyceride levels; both age and triglycerides were negatively associated with factor score, while LDL levels revealed a positive relationship. Both the Executive and Memory/Language factor were only explained by education, whereby more years were associated with better performance. These results provide evidence that individual cholesterol lipoproteins and triglycerides may differentially impact cognitive function, over and above other common CVD risk factors and ApoE status. Our findings demonstrate the importance of consideration of vascular risk factors, such as cholesterol, in studies of cognitive aging.
Wentz, Laurel; Liu, Pei-Yang; Haymes, Emily; Ilich, Jasminka Z
2011-04-01
The purpose of this study was to review incidence of stress fractures in military and athlete populations and identify factors explaining causes and differences in the incidence among genders. Searches were conducted using several major databases. The studies were included if they were original studies including both male and female subjects and their aim was to identify incidence rates and risk factors contributing to the development of stress fractures. Of several thousand studies, 11 focusing on military populations and 10 on athletes are discussed. In both populations, females had higher incidence of stress fractures, with incidence of approximately 3% and approximately 9.2% for males and females, respectively, in military populations and approximately 6.5% and approximately 9.7%, respectively, in athletes. Factors possibly explaining why females are more susceptible to stress fractures include bone anatomy, lower aerobic capacity, smaller muscle, and poor diet. However, both female recruits and athletes with normal weight and bone health are less likely to develop stress fractures, showing that gender is less important than the overall physical shape/condition.
Determinants of Default in P2P Lending
2015-01-01
This paper studies P2P lending and the factors explaining loan default. This is an important issue because in P2P lending individual investors bear the credit risk, instead of financial institutions, which are experts in dealing with this risk. P2P lenders suffer a severe problem of information asymmetry, because they are at a disadvantage facing the borrower. For this reason, P2P lending sites provide potential lenders with information about borrowers and their loan purpose. They also assign a grade to each loan. The empirical study is based on loans’ data collected from Lending Club (N = 24,449) from 2008 to 2014 that are first analyzed by using univariate means tests and survival analysis. Factors explaining default are loan purpose, annual income, current housing situation, credit history and indebtedness. Secondly, a logistic regression model is developed to predict defaults. The grade assigned by the P2P lending site is the most predictive factor of default, but the accuracy of the model is improved by adding other information, especially the borrower’s debt level. PMID:26425854
Determinants of Default in P2P Lending.
Serrano-Cinca, Carlos; Gutiérrez-Nieto, Begoña; López-Palacios, Luz
2015-01-01
This paper studies P2P lending and the factors explaining loan default. This is an important issue because in P2P lending individual investors bear the credit risk, instead of financial institutions, which are experts in dealing with this risk. P2P lenders suffer a severe problem of information asymmetry, because they are at a disadvantage facing the borrower. For this reason, P2P lending sites provide potential lenders with information about borrowers and their loan purpose. They also assign a grade to each loan. The empirical study is based on loans' data collected from Lending Club (N = 24,449) from 2008 to 2014 that are first analyzed by using univariate means tests and survival analysis. Factors explaining default are loan purpose, annual income, current housing situation, credit history and indebtedness. Secondly, a logistic regression model is developed to predict defaults. The grade assigned by the P2P lending site is the most predictive factor of default, but the accuracy of the model is improved by adding other information, especially the borrower's debt level.
Pediatric IBS: an overview on pathophysiology, diagnosis and treatment.
Chogle, Ashish; Mintjens, Stijn; Saps, Miguel
2014-04-01
Irritable bowel syndrome (IBS) is a common disorder in children and adults. The pathogenesis and pathophysiology of IBS remains incompletely understood. The biopsychosocial model, which conceptualizes chronic pain as a dysregulation of the gut-brain-homeostasis with peripheral and central factors mutually influencing each other, is the most accepted framework to explain IBS. Twin and family aggregation studies suggest a genetic component that does not exclusively explain the higher prevalence of IBS in certain families. Social learning (environmental factors) and maladaptive coping predispose children to develop IBS with greater disability and more frequent medical consultations. Early-life events constitute an additional risk factor for the development of IBS and other functional gastrointestinal disorders (FGIDs). Children with a history of cow's milk protein hypersensitivity or abdominal surgeries have a higher prevalence of IBS and other FGIDs years later. IBS frequently follows an episode of acute gastrointestinal inflammation (infectious or non-infectious). This article discusses the importance, known pathophysiological mechanisms, clinical approach, and evidence-based therapeutic options for the management of IBS in children and adolescents. Copyright 2014, SLACK Incorporated.
Personality and prosocial behavior: linking basic traits and social value orientations.
Hilbig, Benjamin E; Glöckner, Andreas; Zettler, Ingo
2014-09-01
Concerning the dispositional determinants of prosocial behavior and cooperation, work based on the classic 5 personality factors, and especially Agreeableness, has turned out somewhat inconsistent. A clearer picture has emerged from consideration of the HEXACO model of personality--though supported entirely by hypothetical behavior as criterion, so far. Thus, in 2 studies and a reanalysis, we investigated "actual behavior" in the form of individually and socially consequential distribution decisions. As expected, HEXACO Honesty-Humility consistently predicted prosocial behavior, including a theory-consistent pattern on the facet level. Importantly, this pattern might explain why five-factor Agreeableness has only sometimes been found to account for prosocial behavior. Indeed, further results indicate that five-factor Agreeableness comprises some aspects that are predictive of prosocial behavior--aspects well covered by HEXACO Honesty-Humility--but also others that play no role for this criterion. As such, the links between five-factor Agreeableness and prosocial behavior are well-covered by HEXACO Honesty-Humility, but not vice versa. Taken together, these findings hint that especially HEXACO Honesty-Humility (and certain aspects of five-factor Agreeableness) account for prosocial behavior--thus explaining previous inconsistencies and providing a more nuanced understanding of the links between basic personality and prosocial or cooperative behavior. 2014 APA, all rights reserved
Sodeify, Roghieh; Vanaki, Zohreh; Mohammadi, Eesa
2013-01-01
Background: Following professional standards is the main concern of all managers in organizations. The functions of nurses are essential for both productivity and improving health organizations. In human resources management, supporting nursing profession is of ultimate importance. However, nurses’ experiences of perceived support, which are affected by various factors in workplace, have not been clearly explained yet. Thus, this study aimed to explain nurses’ experiences of perceived support and their contributing factors. Materials and Methods: This study is a qualitative research in which 12 nurses were selected through purposive sampling among nurses in university hospitals affiliated to University of Medical Sciences, Urmia, Iran, during 2011-2012. Data collection was conducted through deep interviews with semi-structural questions. All interviews were first recorded and then transcribed. Finally, data were analyzed through conventional content analysis. Results: The four main themes indicated that nurses experienced their workplace as non-supportive. Themes such as poor organizational climate, low social dignity, poor work conditions, and managers’ ignorance to individual and professional values were considered as inhibitory factors to support. Conclusion: Nursing managers can promote nurses’ positive support perceptions through recognizing inhibitory factors and applying fair solutions and take benefits of their positive consequences including high efficacy, self-esteem, and organizational commitment to promote the quality of care. PMID:23983753
Critical factors for the recovery of marine mammals.
Lotze, Heike K; Flemming, Joanna Mills; Magera, Anna M
2017-12-01
{en} Over the past decades, much research has focused on understanding the critical factors for marine extinctions with the aim of preventing further species losses in the oceans. Although conservation and management strategies are enabling several species and populations to recover, others remain at low abundance levels or continue to decline. To understand these discrepancies, we used a published database on abundance trends of 137 populations of marine mammals worldwide and compiled data on 28 potentially critical factors for recovery. We then applied random forests and additive mixed models to determine which intrinsic and extrinsic factors are critical for the recovery of marine mammals. A mix of life-history characteristics, ecological traits, phylogenetic relatedness, population size, geographic range, human impacts, and management efforts explained why populations recovered or not. Consistently, species with lower age at maturity and intermediate habitat area were more likely to recover, which is consistent with life-history and ecological theory. Body size, trophic level, social interactions, dominant habitat, ocean basin, and habitat disturbance also explained some differences in recovery patterns. Overall, a variety of intrinsic and extrinsic factors were important for species' recovery, pointing to cumulative effects. Our results provide insight for improving conservation and management strategies to enhance recoveries in the future. © 2017 Society for Conservation Biology.
Hazuda, Helen P.
2015-01-01
Background Mexican Americans comprise the most rapidly growing segment of the older US population and are reported to have poorer functional health than European Americans, but few studies have examined factors contributing to ethnic differences in walking speed between Mexican Americans and European Americans. Objective The purpose of this study was to examine factors that contribute to walking speed and observed ethnic differences in walking speed in older Mexican Americans and European Americans using the disablement process model (DPM) as a guide. Design This was an observational, cross-sectional study. Methods Participants were 703 Mexican American and European American older adults (aged 65 years and older) who completed the baseline examination of the San Antonio Longitudinal Study of Aging (SALSA). Hierarchical regression models were performed to identify the contribution of contextual, lifestyle/anthropometric, disease, and impairment variables to walking speed and to ethnic differences in walking speed. Results The ethic difference in unadjusted mean walking speed (Mexican Americans=1.17 m/s, European Americans=1.29 m/s) was fully explained by adjustment for contextual (ie, age, sex, education, income) and lifestyle/anthropometric (ie, body mass index, height, physical activity) variables; adjusted mean walking speed in both ethnic groups was 1.23 m/s. Contextual variables explained 20.3% of the variance in walking speed, and lifestyle/anthropometric variables explained an additional 8.4%. Diseases (ie, diabetes, stroke, chronic obstructive pulmonary disease) explained an additional 1.9% of the variance in walking speed; impairments (ie, FEV1, upper leg pain, and lower extremity strength and range of motion) contributed an additional 5.5%. Thus, both nonmodifiable (ie, contextual, height) and modifiable (ie, impairments, body mass index, physical activity) factors contributed to walking speed in older Mexican Americans and European Americans. Limitations The study was conducted in a single geographic area and included only Mexican American Hispanic individuals. Conclusions Walking speed in older Mexican Americans and European Americans is influenced by modifiable and nonmodifiable factors, underscoring the importance of the DPM framework, which incorporates both factors into the physical therapist patient/client management process. PMID:25592187
When politics froze fashion: the effect of the Cultural Revolution on naming in Beijing.
Obukhova, Elena; Zuckerman, Ezra W; Zhang, Jiayin
2014-09-01
The authors examine the popularity of boys' given names in Beijing before and after the onset of the Cultural Revolution to clarify how exogenous and endogenous factors interact to shape fashion. Whereas recent work in the sociology of culture emphasizes the importance of endogenous processes in explaining fashion, their analysis demonstrates two ways in which politics shaped cultural expression during the Cultural Revolution: by promoting forms of expression reflecting prevailing political ideology and by limiting individuals' willingness to act differently. As argued by Lieberson and developed further in this article, the second condition is important because endogenous fashion cycles require a critical mass of individuals who seek to differentiate themselves from common practice. Exogenous factors can influence the operation of the endogenous factors. The authors discuss the implications of their study for understanding the nature of conformity under authoritarian regimes and social conditions supporting individual expression.
Mucosal Immunology of Food Allergy
Berin, M. Cecilia; Sampson, Hugh A.
2013-01-01
Food allergies are increasing in prevalence at a higher rate than can be explained by genetic factors, suggesting a role for as yet unidentified environmental factors. In this review, we summarize the state of knowledge about the healthy immune response to antigens in the diet and the basis of immune deviation that results in IgE sensitization and allergic reactivity to foods. The intestinal epithelium forms the interface between the external environment and the mucosal immune system, and emerging data suggest that the interaction between intestinal epithelial cells and mucosal dendritic cells is of particular importance in determining the outcome of immune responses to dietary antigens. Exposure to food allergens through non-oral routes, in particular through the skin, is increasingly recognized as a potentially important factor in the increasing rate of food allergy. There are many open questions on the role of environmental factors such as dietary factors and microbiota in the development of food allergy, but data suggest that both have an important modulatory effect on the mucosal immune system. Finally, we discuss recent developments in our understanding of immune mechanisms of clinical manifestations of food allergy. New experimental tools, particularly in the field of genomics and microbiome, are likely to shed light on factors responsible for the growing clinical problem of food allergy. PMID:23660362
Afroz, Rafia; Rahman, Ataur; Masud, Muhammad Mehedi; Akhtar, Rulia
2017-01-01
The focus of this study is to analyze the level of knowledge, awareness, and attitude toward plastic waste and to distinguish the key drivers that encourage the households in Kuala Lumpur, Malaysia, to participate in "No plastic campaign," This study used the logistic regression model to explain the factors that may affect the willingness to participate (WTP) of households in the campaign. In this study, it is found that 35 % of households are willing to participate in the campaign. The results of the study also indicate that people who are more informed and more convinced of their knowledge have a more positive attitude toward recycling than their counterparts do. Furthermore, this study provides additional evidence of the level and classification of importance of motivating factors for plastic recycling, using the modified average and coefficient of variation of the models. From the analysis, the factor "helps reduce landfill use" is found as the most important factor and the factor of "raising money for charity" is found as the least important factor that motivates households to participate in recycling. The determinations of the study suggest some strategies that could hold implications for government and households to boost them to participate in the campaign "No Plastic Bag."
NASA Astrophysics Data System (ADS)
Le Duy, Nguyen; Heidbüchel, Ingo; Meyer, Hanno; Merz, Bruno; Apel, Heiko
2018-02-01
This study analyzes the influence of local and regional climatic factors on the stable isotopic composition of rainfall in the Vietnamese Mekong Delta (VMD) as part of the Asian monsoon region. It is based on 1.5 years of weekly rainfall samples. In the first step, the isotopic composition of the samples is analyzed by local meteoric water lines (LMWLs) and single-factor linear correlations. Additionally, the contribution of several regional and local factors is quantified by multiple linear regression (MLR) of all possible factor combinations and by relative importance analysis. This approach is novel for the interpretation of isotopic records and enables an objective quantification of the explained variance in isotopic records for individual factors. In this study, the local factors are extracted from local climate records, while the regional factors are derived from atmospheric backward trajectories of water particles. The regional factors, i.e., precipitation, temperature, relative humidity and the length of backward trajectories, are combined with equivalent local climatic parameters to explain the response variables δ18O, δ2H, and d-excess of precipitation at the station of measurement. The results indicate that (i) MLR can better explain the isotopic variation in precipitation (R2 = 0.8) compared to single-factor linear regression (R2 = 0.3); (ii) the isotopic variation in precipitation is controlled dominantly by regional moisture regimes (˜ 70 %) compared to local climatic conditions (˜ 30 %); (iii) the most important climatic parameter during the rainy season is the precipitation amount along the trajectories of air mass movement; (iv) the influence of local precipitation amount and temperature is not significant during the rainy season, unlike the regional precipitation amount effect; (v) secondary fractionation processes (e.g., sub-cloud evaporation) can be identified through the d-excess and take place mainly in the dry season, either locally for δ18O and δ2H, or along the air mass trajectories for d-excess. The analysis shows that regional and local factors vary in importance over the seasons and that the source regions and transport pathways, and particularly the climatic conditions along the pathways, have a large influence on the isotopic composition of rainfall. Although the general results have been reported qualitatively in previous studies (proving the validity of the approach), the proposed method provides quantitative estimates of the controlling factors, both for the whole data set and for distinct seasons. Therefore, it is argued that the approach constitutes an advancement in the statistical analysis of isotopic records in rainfall that can supplement or precede more complex studies utilizing atmospheric models. Due to its relative simplicity, the method can be easily transferred to other regions, or extended with other factors. The results illustrate that the interpretation of the isotopic composition of precipitation as a recorder of local climatic conditions, as for example performed for paleorecords of water isotopes, may not be adequate in the southern part of the Indochinese Peninsula, and likely neither in other regions affected by monsoon processes. However, the presented approach could open a pathway towards better and seasonally differentiated reconstruction of paleoclimates based on isotopic records.
Audino, Lívia D; Murphy, Stephen J; Zambaldi, Ludimila; Louzada, Julio; Comita, Liza S
2017-09-01
There is increasing recognition that community assembly theory can offer valuable insights for ecological restoration. We studied community assembly processes following tropical forest restoration efforts, using dung beetles (Scarabaeinae) as a focal taxon to investigate taxonomic and functional patterns of biodiversity recovery. We evaluated the relative importance of the local environment (i.e., canopy cover, understory cover, tree basal area, and soil texture), landscape context (i.e., habitat patch proximity and availability and percentage of surrounding area classified as natural forest or Eucalyptus spp. plantation), and space (i.e., spatial proximity of the study areas to estimate dispersal limitation or unmeasured spatially structured processes) on dung beetle species and functional trait composition across a gradient of 15 restoration sites in Brazilian Atlantic Forest. We also assessed which factors were the primary determinants in the establishment of individual dung beetle functional groups, classified according to size, food relocation habit, diet, and period of flight activity. Both species and functional trait composition were most strongly influenced by the local environment, indicating that assembly was predominantly driven by niche-based processes. Most of the variation explained by space was co-explained by local environment and landscape context, ruling out a strong influence of dispersal limitation and random colonization on assembly following restoration. In addition, nearly all of the variance explained by landscape context was co-explained by local environment, suggesting that arrival and establishment at a site depends on both local and landscape-scale environmental factors. Despite strong evidence for niche-based assembly, a large amount of variation remained unexplained in all models, suggesting that stochastic processes and/or unmeasured environmental variables also play an important role. The relative importance of local environment, landscape context, and space changed considerably when analyzing the assembly mechanisms of each functional group separately. Therefore, to recover distinct functional traits in restoration sites, it may be necessary to manipulate different components of the local environment and surrounding landscape. Overall, this study shows that assembly rules can help to better understand recovery processes, enabling improvement of future restoration efforts. © 2017 by the Ecological Society of America.
NASA Astrophysics Data System (ADS)
Konduru, R.; Gupta, A.; Matsumoto, J.; Takahashi, H. G.
2017-12-01
In order to explain monsoon circulation, surface temperature gradients described as most traditional concept. However, it cannot explain certain important aspects of monsoon circulation. Later, convective quasi-equilibrium framework and vertically integrated atmospheric energy budget has become recognized theories to explain the monsoon circulation. In this article, same theories were analyzed and observed for the duration 1979-2010 over south Asian summer monsoon region. With the help of NCEP-R2, NOAA 20th Century, and Era-Interim reanalysis an important feature was noticed pertained to subcloud layer entropy and vertical moist static energy. In the last 32 years, subcloud layer entropy and vertically integrated moist static energy has shown significant seasonal warming all over the region with peak over the poleward flank of the cross-equatorial cell. The important reason related to the warming was found to be increase in surface enthalpy fluxes. Instead, other dynamical contributions pertained to the warming was also observed. Increase in positive anomalies of vertical advection of moist static energy over northern Bay of Bengal, Central India, Peninsular India, Eastern Arabian Sea, and Equatorial Indian Ocean was found to be an important dynamic factor contributing for warming of vertically integrated moist static energy. Along with it vertical moist stability has also supported the argument. Similar interpretations were perceived in the AMIP simulation of CCSM4 model. Further modeling experiments on this warming will be helpful to know the exact mechanism behind it.
Environmental drivers of Ixodes ricinus abundance in forest fragments of rural European landscapes.
Ehrmann, Steffen; Liira, Jaan; Gärtner, Stefanie; Hansen, Karin; Brunet, Jörg; Cousins, Sara A O; Deconchat, Marc; Decocq, Guillaume; De Frenne, Pieter; De Smedt, Pallieter; Diekmann, Martin; Gallet-Moron, Emilie; Kolb, Annette; Lenoir, Jonathan; Lindgren, Jessica; Naaf, Tobias; Paal, Taavi; Valdés, Alicia; Verheyen, Kris; Wulf, Monika; Scherer-Lorenzen, Michael
2017-09-06
The castor bean tick (Ixodes ricinus) transmits infectious diseases such as Lyme borreliosis, which constitutes an important ecosystem disservice. Despite many local studies, a comprehensive understanding of the key drivers of tick abundance at the continental scale is still lacking. We analyze a large set of environmental factors as potential drivers of I. ricinus abundance. Our multi-scale study was carried out in deciduous forest fragments dispersed within two contrasting rural landscapes of eight regions, along a macroclimatic gradient stretching from southern France to central Sweden and Estonia. We surveyed the abundance of I. ricinus, plant community composition, forest structure and soil properties and compiled data on landscape structure, macroclimate and habitat properties. We used linear mixed models to analyze patterns and derived the relative importance of the significant drivers. Many drivers had, on their own, either a moderate or small explanatory value for the abundance of I. ricinus, but combined they explained a substantial part of variation. This emphasizes the complex ecology of I. ricinus and the relevance of environmental factors for tick abundance. Macroclimate only explained a small fraction of variation, while properties of macro- and microhabitat, which buffer macroclimate, had a considerable impact on tick abundance. The amount of forest and the composition of the surrounding rural landscape were additionally important drivers of tick abundance. Functional (dispersules) and structural (density of tree and shrub layers) properties of the habitat patch played an important role. Various diversity metrics had only a small relative importance. Ontogenetic tick stages showed pronounced differences in their response. The abundance of nymphs and adults is explained by the preceding stage with a positive relationship, indicating a cumulative effect of drivers. Our findings suggest that the ecosystem disservices of tick-borne diseases, via the abundance of ticks, strongly depends on habitat properties and thus on how humans manage ecosystems from the scale of the microhabitat to the landscape. This study stresses the need to further evaluate the interaction between climate change and ecosystem management on I. ricinus abundance.
The Significance of the Psychosocial Factors Influence in Pathogenesis of Cardiovascular Disease
Masic, Izet; Alajbegovic, Jasmin
2013-01-01
Background: Cardiovascular diseases (CVD) are the leading cause of death in the world today. Risk factors are those factors that influence the development of CVD. Risk factors can be divided into materialistic (genetic predisposition, smoking, alcohol) and non-materialistic (psychosocial factors). Our goal is to note the role of the health system, to emphasize the importance of psychosocial factors in the pathogenesis of CVD, explain the relationship between psychosocial factors and other risk factors, stress the importance of prevention through the provision of management of the cardiovascular system (CVS) diseases. Methods: A descriptive analysis was performed on scientific studies in several published articles in journals on CVS: Public Health Reviews, CVD, European Heart Journal, Materia Socio Medica and other indexed journals that publish articles on CVS. Results and Conclusions: The importance and role of the health system in the early detection, diagnosis, therapy and CVS disease prevention is presented through three thematic areas: (a) The incidence and prevalence of CVS diseases; (b) treatment of CVS diseases and (c) promotion of health in patients with CVS disease and those the risk of their occurrence. Health promotion is the most important aspect of the health system monitoring. Health promotion is adequately implemented ifthe management ofCVD is proper. The main objectives of CVD management are: Preventing or delaying the occurrence of CVD, reducing the number and severity of worsening and complications of CVD. Management Includes: Individual and family, the health system and the community. Materialistic and non-materialistic risk factors together contribute to the development of CVD. PMID:24404370
Observations and Modelling of Alternative Tree Cover States of the Boreal Ecosystem
NASA Astrophysics Data System (ADS)
Abis, B.; Brovkin, V.
2017-12-01
Recently, multimodality of the tree cover distribution of the boreal forests has been detected, revealing the existence of three alternative vegetation modes. Identifying which are the regions with a potential for alternative tree cover states, and assessing which are the main factors underlying their existence, is important to project future change of natural vegetation cover and its effect on climate.Through the use of generalised additive models and phase-space analysis, we study the link between tree cover distribution and eight globally-observed environmental factors, such as rainfall, temperature, and permafrost distribution. Using a classification based on these factors, we show the location of areas with potentially alternative tree cover states under the same environmental conditions in the boreal region. Furthermore, to explain the multimodality found in the data and the asymmetry between North America and Eurasia, we study a conceptual model based on tree species competition, and use it to simulate the sensitivity of tree cover to changes in environmental factors.We find that the link between individual environmental variables and tree cover differs regionally. Nonetheless, environmental conditions uniquely determine the vegetation state among the three dominant modes in ˜95% of the cases. On the other hand, areas with potentially alternative tree cover states encompass ˜1.1 million km2, and correspond to possible transition zones with a reduced resilience to disturbances. Employing our conceptual model, we show that multimodality can be explained through competition between tree species with different adaptations to environmental factors and disturbances. Moreover, the model is able to reproduce the asymmetry in tree species distribution between Eurasia and North America. Finally, we find that changes in permafrost could be associated with bifurcation points of the model, corroborating the importance of permafrost in a changing climate.
Quantitative Evaluation of the Environmental Impact Quotient (EIQ) for Comparing Herbicides
Kniss, Andrew R.; Coburn, Carl W.
2015-01-01
Various indicators of pesticide environmental risk have been proposed, and one of the most widely known and used is the environmental impact quotient (EIQ). The EIQ has been criticized by others in the past, but it continues to be used regularly in the weed science literature. The EIQ is typically considered an improvement over simply comparing the amount of herbicides applied by weight. Herbicides are treated differently compared to other pesticide groups when calculating the EIQ, and therefore, it is important to understand how different risk factors affect the EIQ for herbicides. The purpose of this work was to evaluate the suitability of the EIQ as an environmental indicator for herbicides. Simulation analysis was conducted to quantify relative sensitivity of the EIQ to changes in risk factors, and actual herbicide EIQ values were used to quantify the impact of herbicide application rate on the EIQ Field Use Rating. Herbicide use rate was highly correlated with the EIQ Field Use Rating (Spearman’s rho >0.96, P-value <0.001) for two herbicide datasets. Two important risk factors for herbicides, leaching and surface runoff potential, are included in the EIQ calculation but explain less than 1% of total variation in the EIQ. Plant surface half-life was the risk factor with the greatest relative influence on herbicide EIQ, explaining 26 to 28% of the total variation in EIQ for actual and simulated EIQ values, respectively. For herbicides, the plant surface half-life risk factor is assigned values without any supporting quantitative data, and can result in EIQ estimates that are contrary to quantitative risk estimates for some herbicides. In its current form, the EIQ is a poor measure of herbicide environmental impact. PMID:26121252
Quantitative Evaluation of the Environmental Impact Quotient (EIQ) for Comparing Herbicides.
Kniss, Andrew R; Coburn, Carl W
2015-01-01
Various indicators of pesticide environmental risk have been proposed, and one of the most widely known and used is the environmental impact quotient (EIQ). The EIQ has been criticized by others in the past, but it continues to be used regularly in the weed science literature. The EIQ is typically considered an improvement over simply comparing the amount of herbicides applied by weight. Herbicides are treated differently compared to other pesticide groups when calculating the EIQ, and therefore, it is important to understand how different risk factors affect the EIQ for herbicides. The purpose of this work was to evaluate the suitability of the EIQ as an environmental indicator for herbicides. Simulation analysis was conducted to quantify relative sensitivity of the EIQ to changes in risk factors, and actual herbicide EIQ values were used to quantify the impact of herbicide application rate on the EIQ Field Use Rating. Herbicide use rate was highly correlated with the EIQ Field Use Rating (Spearman's rho >0.96, P-value <0.001) for two herbicide datasets. Two important risk factors for herbicides, leaching and surface runoff potential, are included in the EIQ calculation but explain less than 1% of total variation in the EIQ. Plant surface half-life was the risk factor with the greatest relative influence on herbicide EIQ, explaining 26 to 28% of the total variation in EIQ for actual and simulated EIQ values, respectively. For herbicides, the plant surface half-life risk factor is assigned values without any supporting quantitative data, and can result in EIQ estimates that are contrary to quantitative risk estimates for some herbicides. In its current form, the EIQ is a poor measure of herbicide environmental impact.
Bregar, Branko; Skela-Savič, Brigita; Kores Plesničar, Blanka
2018-06-04
Coercive measures are containment methods used in psychiatry to curb patients' disruptive and aggressive behaviours towards themselves, others or objects. The prevalence of the practice of coercive measures in psychiatry is directly related to the attitudes of the staff. When discussing these attitudes, nurses are often particularly singled out. The purpose of the study is to research the impact of individual factors on nurses' attitudes in the decision-making process for the use of coercive measures. A cross-sectional study among all psychiatric nursing staff in Slovenia (n = 367, 79%) was conducted over the years 2013/2014. Standardized questionnaires were used, including a survey of nurses' attitudes to the use of seclusion, the Job Descriptive Index, and the Folkman-Lazarus test. Nurses' attitudes towards special coercive measures are predominantly negative ([Formula: see text] = 11.312, SD = 2.641). The factors that explain a positive attitude are as follows: female gender (β = - 0.236, p < 0.001), fewer years of service (β = - 0.149, p = 0.023), emotion-focused strategies of coping with stress (β = 0.139, p = 0.020), and less-threatening patient behaviour (β = 0.157, p = 0.012). The effects of some known factors did not prove important in the model. Newly recognized factors are "less-threatening patient behaviour" and "emotion-focused strategies of coping with stress". Therefore, attitudes towards special coercive measures in psychiatry must be regarded as contextualized, interactive, and multidimensional phenomena that cannot be explained merely through a defined set of factors.
Olea, Pedro P.; Mateo-Tomás, Patricia; de Frutos, Ángel
2010-01-01
Background Hierarchical partitioning (HP) is an analytical method of multiple regression that identifies the most likely causal factors while alleviating multicollinearity problems. Its use is increasing in ecology and conservation by its usefulness for complementing multiple regression analysis. A public-domain software “hier.part package” has been developed for running HP in R software. Its authors highlight a “minor rounding error” for hierarchies constructed from >9 variables, however potential bias by using this module has not yet been examined. Knowing this bias is pivotal because, for example, the ranking obtained in HP is being used as a criterion for establishing priorities of conservation. Methodology/Principal Findings Using numerical simulations and two real examples, we assessed the robustness of this HP module in relation to the order the variables have in the analysis. Results indicated a considerable effect of the variable order on the amount of independent variance explained by predictors for models with >9 explanatory variables. For these models the nominal ranking of importance of the predictors changed with variable order, i.e. predictors declared important by its contribution in explaining the response variable frequently changed to be either most or less important with other variable orders. The probability of changing position of a variable was best explained by the difference in independent explanatory power between that variable and the previous one in the nominal ranking of importance. The lesser is this difference, the more likely is the change of position. Conclusions/Significance HP should be applied with caution when more than 9 explanatory variables are used to know ranking of covariate importance. The explained variance is not a useful parameter to use in models with more than 9 independent variables. The inconsistency in the results obtained by HP should be considered in future studies as well as in those already published. Some recommendations to improve the analysis with this HP module are given. PMID:20657734
ERIC Educational Resources Information Center
Bendíková, Elena; Dobay, Beáta
2017-01-01
The study explains the importance and the role of physical and sport education in development of a positive attitude toward physical activity and health in adulthood. The empirical study was aimed at finding the factor that contributed to the transfer of respondents' physical activity into their adulthood with regard to their health status. The…
ERIC Educational Resources Information Center
Ziegler, Albert; Fidelman, Marina; Reutlinger, Marold; Vialle, Wilma; Stoeger, Heidrun
2010-01-01
The attainment of exceptional accomplishments requires extremely long periods of time. It has yet to be explained, though, how individuals find the motivation for such protracted learning. Carol Dweck proposed that an incremental theory of an individual's abilities is an important factor in this process since it would account for the optimism…
Depressive status explains a significant amount of the variance in COPD assessment test (CAT) scores
Miravitlles, Marc; Molina, Jesús; Quintano, José Antonio; Campuzano, Anna; Pérez, Joselín; Roncero, Carlos
2018-01-01
Background COPD assessment test (CAT) is a short, easy-to-complete health status tool that has been incorporated into the multidimensional assessment of COPD in order to guide therapy; therefore, it is important to understand the factors determining CAT scores. Methods This is a post hoc analysis of a cross-sectional, observational study conducted in respiratory medicine departments and primary care centers in Spain with the aim of identifying the factors determining CAT scores, focusing particularly on the cognitive status measured by the Mini-Mental State Examination (MMSE) and levels of depression measured by the short Beck Depression Inventory (BDI). Results A total of 684 COPD patients were analyzed; 84.1% were men, the mean age of patients was 68.7 years, and the mean forced expiratory volume in 1 second (%) was 55.1%. Mean CAT score was 21.8. CAT scores correlated with the MMSE score (Pearson’s coefficient r=−0.371) and the BDI (r=0.620), both p<0.001. In the multivariate analysis, the usual COPD severity variables (age, dyspnea, lung function, and comorbidity) together with MMSE and BDI scores were significantly associated with CAT scores and explained 45% of the variability. However, a model including only MMSE and BDI scores explained up to 40% and BDI alone explained 38% of the CAT variance. Conclusion CAT scores are associated with clinical variables of severity of COPD. However, cognitive status and, in particular, the level of depression explain a larger percentage of the variance in the CAT scores than the usual COPD clinical severity variables. PMID:29563782
Miravitlles, Marc; Molina, Jesús; Quintano, José Antonio; Campuzano, Anna; Pérez, Joselín; Roncero, Carlos
2018-01-01
COPD assessment test (CAT) is a short, easy-to-complete health status tool that has been incorporated into the multidimensional assessment of COPD in order to guide therapy; therefore, it is important to understand the factors determining CAT scores. This is a post hoc analysis of a cross-sectional, observational study conducted in respiratory medicine departments and primary care centers in Spain with the aim of identifying the factors determining CAT scores, focusing particularly on the cognitive status measured by the Mini-Mental State Examination (MMSE) and levels of depression measured by the short Beck Depression Inventory (BDI). A total of 684 COPD patients were analyzed; 84.1% were men, the mean age of patients was 68.7 years, and the mean forced expiratory volume in 1 second (%) was 55.1%. Mean CAT score was 21.8. CAT scores correlated with the MMSE score (Pearson's coefficient r =-0.371) and the BDI ( r =0.620), both p <0.001. In the multivariate analysis, the usual COPD severity variables (age, dyspnea, lung function, and comorbidity) together with MMSE and BDI scores were significantly associated with CAT scores and explained 45% of the variability. However, a model including only MMSE and BDI scores explained up to 40% and BDI alone explained 38% of the CAT variance. CAT scores are associated with clinical variables of severity of COPD. However, cognitive status and, in particular, the level of depression explain a larger percentage of the variance in the CAT scores than the usual COPD clinical severity variables.
Male homosexuality: nature or culture?
Jannini, Emmanuele A; Blanchard, Ray; Camperio-Ciani, Andrea; Bancroft, John
2010-10-01
Debate continues on whether or not male homosexuality (MH) is a result of biological or cultural factors. The debate persists despite the fact that these two sides have different abilities to create a scientific environment to support their cause. Biological theorists produced evidence, however, that these are not always robust. On the other hand, social theorists, without direct evidence confirming their positions, criticize, with good argument, methods and results of the other side. The aim of this Controversy is to understand the reasons of both perspectives. Two scientists (R.B. and A.C.C.) with expertise in the area of biology of MH were asked to contribute their opinions. The nurture position is discussed by a third expert in sexology (J.B.). Expert opinion supported by the critical review of the currently available literature. The role of the Controversy's editor (E.A.J.) is to highlight the strengths and weaknesses of both sides. The two experts of the biological issue answer with their data to the questions: “Is male homosexuality partly explainable by immunology?” and “How is male homosexuality a Darwinian paradox?”, respectively. Genetic and immunological factors, birth order, and fertility of relatives are largely discussed. Finally, the expert sustaining the idea that culture and experiences are important determining factors in sexual orientation used a psychosocial and holistic perspective to explain his position. The JSM's readers should recognize that there are several biological factors in MH. However, these findings do not seem to be able to explain all cases of homosexuality. Some others may be due to particular environmental factors. The issue is complicated and multifactorial, suggesting that further research should be undertaken to produce the final answer to the question raised in this Controversy section.
Zhu, Yi-feng; Dai, Mei-xia; Zhou, Xiao-hong; Lin, Xia; Mao, Shuo-qian; Yan, Xiao-jun
2015-08-01
Zooplankton samples were seasonally collected at 10 stations in thermal discharge seawaters near Guohua Power Plant in Xiangshan Bay. The abundance data from these samples were pooled and further combined with field environmental factors, then generalised dissimilarity modelling (GDM) was used to explore the effects of environmental factors on β diversity of zooplankton community. The results showed that altogether 95 species of zooplankton belonging to 14 taxa were found. In these taxa, small zooplankton with 62.6% of abundance was the main taxa, while copepods dominated in adult groups, which abundance accounted for 35.3%. According to Whittaker's definition and additive partition, a diversity accounted for 36.3% and β diversity 63.7%. Environmental factors explained 43.8% of β diversity, and geographical distance between sampling sites had no effect on β diversity. However, there were still 19.9% of β diversity remained to be explained. After GDM fitting, there were nine environmental variables affecting zooplankton β diversity and explaining 68.8% of β diversity. The variables contributing to β diversity from high to low were seasonal water temperature, dissolved oxygen, seawater temperature increment, conductivity, suspended particulate matter, salinity, transparency, water depth and redox potential, respectively. Seasonal water temperature, dissolved oxygen and seawater temperature increment were the most important factors for driving β diversity changes, and accounted for 23.9%, 13.7% and 9.7% of absolute contribution to the interpretable portion of the β diversity, respectively. When seasonal water temperature, dissolved oxygen and seawater temperature increment were below 25 °C, greater than 5 mg · L(-1) and over 1 °C, respectively, β diversity rapidly increased with the increasing variable gradients. Furthermore, other predictors had little effect on β diversity.
High intelligence prevents the negative impact of anxiety on working memory.
Chuderski, Adam
2015-01-01
Using a large sample and the confirmatory factor analysis, the study investigated the relationships between anxiety, working memory (WM) and (fluid) intelligence. The study showed that the negative impact of anxiety on WM functioning diminishes with increasing intelligence, and that anxiety can significantly affect WM only in people below average intelligence. This effect could not be fully explained by the sheer differences in WM capacity (WMC), suggesting the importance of higher-level cognition in coping with anxiety. Although intelligence moderated the impact of anxiety on WM, it was only weakly related to anxiety. In contrast to previous studies, anxiety explained the substantial amount of WMC variance (17.8%) in less intelligent participants, but none of the variance in more intelligent ones. These results can be explained in terms of either increased motivation of intelligent but anxious people to cope with a WM task, or their ability to compensate decrements in WM.
Hodge, Andrew; Firth, Sonja; Bermejo, Raoul; Zeck, Willibald; Jimenez-Soto, Eliana
2016-07-06
Despite achieving some success, wealth-related disparities in the utilisation of maternal and child health services persist in the Philippines. The aim of this study is to decompose the principal factors driving the wealth-based utilisation gap. Using national representative data from the 2013 Philippines Demographic and Health Survey, we examine the extent overall differences in the utilisation of maternal health services can be explained by observable factors. We apply nonlinear Blinder-Oaxaca-type decomposition methods to quantify the effect of differences in measurable characteristics on the wealth-based coverage gap in facility-based delivery. The mean coverage of facility-based deliveries was respectively 41.1 % and 74.6 % for poor and non-poor households. Between 67 and 69 % of the wealth-based coverage gap was explained by differences in observed characteristics. After controlling for factors characterising the socioeconomic status of the household (i.e. the mothers' and her partners' education and occupation), the birth order of the child was the major factor contributing to the disparity. Mothers' religion and the subjective distance to the health facility were also noteworthy. This study has found moderate wealth-based disparities in the utilisation of institutional delivery in the Philippines. The results confirm the importance of recent efforts made by the Philippine government to implement equitable, pro-poor focused health programs in the most deprived geographic areas of the country. The importance of addressing the social determinants of health, particularly education, as well as developing and implementing effective strategies to encourage institutional delivery for higher order births, should be prioritised.
The effects of sexual orientation on state legislators' behavior and priorities.
Herrick, Rebekah
2009-01-01
This article explores whether sexual orientation, surrogate representation, and political factors affect legislators' work on gay, lesbian, and bisexual (GLB) interests, and whether the latter explains away the influence of sexual orientation. A survey of openly GLB state legislators and their colleagues was conducted to measure legislators' campaign issues, legislative priorities, surrogate representation, and ambition. This information is supplemented with bill introduction and district data. The results indicate that legislators' sexual orientation strongly influences their work on GLB issues and although surrogate representation and electoral considerations also affect GLB work, they do not explain away the importance of sexual orientation. The implications of this for the relationship between descriptive and substantive representation are explored.
Padial, André A.; Ceschin, Fernanda; Declerck, Steven A. J.; De Meester, Luc; Bonecker, Cláudia C.; Lansac-Tôha, Fabio A.; Rodrigues, Liliana; Rodrigues, Luzia C.; Train, Sueli; Velho, Luiz F. M.; Bini, Luis M.
2014-01-01
Recently, community ecologists are focusing on the relative importance of local environmental factors and proxies to dispersal limitation to explain spatial variation in community structure. Albeit less explored, temporal processes may also be important in explaining species composition variation in metacommunities occupying dynamic systems. We aimed to evaluate the relative role of environmental, spatial and temporal variables on the metacommunity structure of different organism groups in the Upper Paraná River floodplain (Brazil). We used data on macrophytes, fish, benthic macroinvertebrates, zooplankton, periphyton, and phytoplankton collected in up to 36 habitats during a total of eight sampling campaigns over two years. According to variation partitioning results, the importance of predictors varied among biological groups. Spatial predictors were particularly important for organisms with comparatively lower dispersal ability, such as aquatic macrophytes and fish. On the other hand, environmental predictors were particularly important for organisms with high dispersal ability, such as microalgae, indicating the importance of species sorting processes in shaping the community structure of these organisms. The importance of watercourse distances increased when spatial variables were the main predictors of metacommunity structure. The contribution of temporal predictors was low. Our results emphasize the strength of a trait-based analysis and of better defining spatial variables. More importantly, they supported the view that “all-or- nothing” interpretations on the mechanisms structuring metacommunities are rather the exception than the rule. PMID:25340577
Oliveira, Eliana Faria; Martinez, Pablo Ariel; São-Pedro, Vinícius Avelar; Gehara, Marcelo; Burbrink, Frank Thomas; Mesquita, Daniel Oliveira; Garda, Adrian Antonio; Colli, Guarino Rinaldi; Costa, Gabriel Correa
2018-03-01
Spatial patterns of genetic variation can help understand how environmental factors either permit or restrict gene flow and create opportunities for regional adaptations. Organisms from harsh environments such as the Brazilian semiarid Caatinga biome may reveal how severe climate conditions may affect patterns of genetic variation. Herein we combine information from mitochondrial DNA with physical and environmental features to study the association between different aspects of the Caatinga landscape and spatial genetic variation in the whiptail lizard Ameivula ocellifera. We investigated which of the climatic, environmental, geographical and/or historical components best predict: (1) the spatial distribution of genetic diversity, and (2) the genetic differentiation among populations. We found that genetic variation in A. ocellifera has been influenced mainly by temperature variability, which modulates connectivity among populations. Past climate conditions were important for shaping current genetic diversity, suggesting a time lag in genetic responses. Population structure in A. ocellifera was best explained by both isolation by distance and isolation by resistance (main rivers). Our findings indicate that both physical and climatic features are important for explaining the observed patterns of genetic variation across the xeric Caatinga biome.
Manier, Mollie K; Arnold, Stevan J
2006-12-07
Identifying ecological factors associated with population genetic differentiation is important for understanding microevolutionary processes and guiding the management of threatened populations. We identified ecological correlates of several population genetic parameters for three interacting species (two garter snakes and an anuran) that occupy a common landscape. Using multiple regression analysis, we found that species interactions were more important in explaining variation in population genetic parameters than habitat and nearest-neighbour characteristics. Effective population size was best explained by census size, while migration was associated with differences in species abundance. In contrast, genetic distance was poorly explained by the ecological correlates that we tested, but geographical distance was prominent in models for all species. We found substantially different population dynamics for the prey species relative to the two predators, characterized by larger effective sizes, lower gene flow and a state of migration-drift equilibrium. We also identified an escarpment formed by a series of block faults that serves as a barrier to dispersal for the predators. Our results suggest that successful landscape-level management should incorporate genetic and ecological data for all relevant species, because even closely associated species can exhibit very different population genetic dynamics on the same landscape.
Ungar, Nadine; Wiskemann, Joachim; Sieverding, Monika
2016-01-01
Background: Physical activity (PA) can support cancer patients during medical treatment by reducing side-effects and increasing quality of life. However, PA levels mostly decline after diagnosis. Which factors can explain if patients are able to remain or even increase their PA level? Self-efficacy is an important cognitive factor that has been linked to cancer patients' PA across many studies. In contrast, affective factors such as PA enjoyment have rarely been examined. We compare the influence of self-efficacy and PA enjoyment on cancer patients' PA levels after completion of an exercise or stress-management intervention. Methods: Outpatient cancer patients [N = 72; 54% female; M = 56 years, SD = 12.34; most with breast or colon cancer (34%, 15%)] were enrolled in the MOTIVACTION study, a 4-week intervention (1 h counseling followed by weekly phone calls), with pre-test (T1), post-test (T2), and a 10-week follow-up (T3). Participants were randomized to either an exercise intervention (emphasizing self-regulatory strategies for behavior change) or to a stress management intervention (coping and relaxation techniques). Sixty-seven patients remained in the study and completed the SQUASH assessment of PA, a measure of maintenance self-efficacy (7 items, Cronbach's α = 0.88) and PA enjoyment (2 items, Cronbach's α = 0.89). Regression analyses were calculated with PA level (at T2 and T3) as dependent variable and relative weight analyses were conducted. The study was registered at clinicalTrials.gov (unique identifier:NCT01576107; URL: https://clinicaltrials.gov/ct2/show/NCT01576107?term=motivaction&rank=1). Results: Baseline self-efficacy and change in PA enjoyment significantly predicted cancer patients' PA level at T2 adjusting for baseline PA and type of intervention. Relative weight (RW) analysis revealed that PA enjoyment (baseline and change together) explained 34.3% of the dependent variable, self-efficacy (baseline and change) explained 38.4%. At follow-up, self-efficacy was still a significant predictor of PA (RW = 74.6%), whereas PA enjoyment was no longer a relevant factor (RW = 5.2%). Conclusion: The affective factor PA enjoyment was equally important as self-efficacy for predicting cancer patient' PA level directly after completion of the intervention. Reasons for the reduced relevance at follow-up and a broader range of affective factors should be analyzed in future studies on cancer patients' PA level. PMID:27445882
Antoniou, Evangelia E; Fowler, Tom; Reed, Keith; Southwood, Taunton R; McCleery, Joseph P; Zeegers, Maurice P
2014-10-14
To estimate the heritability of child behaviour problems and investigate the association between maternal pre-pregnancy overweight and child behaviour problems in a genetically sensitive design. Observational cross-sectional study. The Twins and Multiple Births Association Heritability Study (TAMBAHS) is an online UK-wide volunteer-based study investigating the development of twins from birth until 5 years of age. A total of 443 (16% of the initial registered members) mothers answered questions on pre-pregnancy weight and their twins' internalising and externalising problems using the Child Behavior Checklist and correcting for important covariates including gestational age, twins' birth weight, age and sex, mother's educational level and smoking (before, during and after pregnancy). The heritability of behaviour problems and their association with maternal pre-pregnancy weight. The genetic analysis suggested that genetic and common environmental factors account for most of the variation in externalising disorders (an ACE model was the most parsimonious with genetic factors (A) explaining 46% (95% CI 33% to 60%) of the variance, common environment (C) explaining 42% (95% CI 27% to 54%) and non-shared environmental factors (E) explaining 13% (95% CI 10% to 16%) of the variance. For internalising problems, a CE model was the most parsimonious model with the common environment explaining 51% (95% CI 44% to 58%) of the variance and non-shared environment explaining 49% (95% CI 42% to 56%) of the variance. Moreover, the regression analysis results suggested that children of overweight mothers showed a trend (OR=1.10, 95% CI 0.58% to 2.06) towards being more aggressive and exhibit externalising behaviours compared to children of normal weight mothers. Maternal pre-pregnancy weight may play a role in children's aggressive behaviour. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Maeland, J G; Havik, O E
1986-01-01
The relationship between return to work (RTW) within 6 months after a myocardial infarction (MI) and selected demographic factors, characteristics of prior work situation, pre-MI health status, and clinical severity of the MI has been studied in 249 patients below 67 years of age living in urban and rural areas of Western Norway. At the follow-up 8 out of 10 urban patients and 6 out of 10 rural patients were back at work. The RTW rate for the total sample was 73%. Age below 51 years, high educational and income level, working in tertiary industries, and in a job characterized by low physical activity and little psychosocial stress were all factors associated with a favourable work resumption. Multivariate analyses showed that socioeconomic or work-related factors could not fully explain the urban-rural differences in RTW. Stepwise discriminant analysis identified the following factors as important and independent predictors for RTW: Place of residence, age, education, perceived job stress, and clinical complications during hospitalization. Failure to return to work after a MI can be explained by a number of individual and social factors and only to a limited degree by the medical status of the patient. More knowledge is needed concerning the socio-cultural differences among both patients and attending physicians in attitudes towards work resumption after a MI.
Knight, Louise; Nakuti, Janet; Allen, Elizabeth; Gannett, Katherine R; Naker, Dipak; Devries, Karen M
2016-01-01
The nature and structure of the school environment has the potential to shape children's health and well being. Few studies have explored the importance of school-level factors in explaining a child's likelihood of experiencing violence from school staff, particularly in low-resource settings such as Uganda. To quantify to what extent a student's risk of violence is determined by school-level factors we fitted multilevel logistic regression models to investigate associations and present between-school variance partition coefficients. School structural factors, academic and supportive environment are explored. 53% of students reported physical violence from staff. Only 6% of variation in students' experience of violence was due to differences between schools and half the variation was explained by the school-level factors modelled. Schools with a higher proportion of girls are associated with increased odds of physical violence from staff. Students in schools with a high level of student perceptions of school connectedness have a 36% reduced odds of experiencing physical violence from staff, but no other school-level factor was significantly associated. Our findings suggest that physical violence by school staff is widespread across different types of schools in this setting, but interventions that improve students' school connectedness should be considered. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.
Kjerulff, Kristen H; Attanasio, Laura B; Edmonds, Joyce K; Kozhimannil, Katy B; Repke, John T
2017-09-01
Mode of delivery at first childbirth largely determines mode of delivery at subsequent births, so it is particularly important to understand risk factors for cesarean delivery at first childbirth. In this study, we investigated risk factors for cesarean delivery among nulliparous women, with focus on the association between labor induction and cesarean delivery. A prospective cohort study of 2851 nulliparous women with singleton pregnancies who attempted vaginal delivery at hospitals in Pennsylvania, 2009-2011, was conducted. We used nested logistic regression models and multiple mediational analyses to investigate the role of three groups of variables in explaining the association between labor induction and unplanned cesarean delivery-the confounders of maternal characteristics and indications for induction, and the mediating (intrapartum) factors-including cervical dilatation, labor augmentation, epidural analgesia, dysfunctional labor, dystocia, fetal intolerance of labor, and maternal request of cesarean during labor. More than a third of the women were induced (34.3%) and 24.8% underwent cesarean delivery. Induced women were more likely to deliver by cesarean (35.9%) than women in spontaneous labor (18.9%), unadjusted OR 2.35 (95% CI 1.97-2.79). The intrapartum factors significantly mediated the association between labor induction and cesarean delivery (explaining 76.7% of this association), particularly cervical dilatation <3 cm at hospital admission, fetal intolerance of labor, and dystocia. The indications for labor induction only explained 6.2%. Increased risk of cesarean delivery after labor induction among nulliparous women is attributable mainly to lower cervical dilatation at hospital admission and higher rates of labor complications. © 2017 Wiley Periodicals, Inc.
Predictors of childhood immunization completion in a rural population.
Gore, P; Madhavan, S; Curry, D; McClung, G; Castiglia, M; Rosenbluth, S A; Smego, R A
1999-04-01
Despite the availability of effective vaccines, immunization rates among two-year old children continue to be low in many areas of the United States including rural West Virginia. The goal of this study was to identify barriers to childhood immunization in rural West Virginia and determine factors that were important in the completion of the childhood immunization schedule. A telephone survey was used to collect data from a randomly selected sample of 316 mothers, of two-year olds, from 18 rural counties of West Virginia. Results indicated that two-thirds or 65% of the children in the study sample had completed their recommended immunizations by two years of age. Immunization barriers identified in this study include: living in health professional shortage areas, lack of health insurance, negative beliefs and attitudes regarding childhood immunizations, problems accessing the immunization clinic, and a perception of inadequate support from the immunization clinic. Results of the structural equation modeling, using LISREL-8, indicated that 20% of the variation in immunization completion (R2 = 0.197) was explained by attitude towards immunization and perceived support received from the immunization clinic. Furthermore, 42% of the variation in attitude towards immunization (R2 = 0.419) was explained by immunization-related beliefs, and 28% of the variation in immunization-related beliefs (the R2 = 0.277) was explained by general problems faced during immunization and perceived clinic support. The study concluded that positive immunization-related beliefs and attitudes, support from the immunization clinic, and ease of the immunization seeking process are important factors in the timely completion of the childhood immunization schedule.
The impact of preventive health behaviour and social factors on visits to the doctor.
Yom Din, Gregory; Zugman, Zinaida; Khashper, Alla
2014-01-01
The aim of this study is to examine the joint impact of preventive health behavior (PHB) and social and demographic factors on the utilization of primary and secondary medical care under a universal health care system, as measured by visits to the doctor, who were categorized as either a General Practitioner (GP) or Specialist Doctor (SD). An ordered probit model was utilized to analyze data obtained from the 2009 Israeli National Health Survey. The problem of endogeneity between PHB factors and visits to GP was approached using the two-stage residuals inclusion and instrumental variables method. We found a positive effect of PHB on visits to the doctor while the addition of the PHB factors to the independent variables resulted in important changes in explaining visits to GP (in values of the estimates, in their sign, and in their statistical significance), and only in slight changes for visits to SD. A 1% increase in PHB factors results in increasing the probability to visit General Practitioner in the last year in 0.6%. The following variables were identified as significant in explaining frequency of visits to the doctor: PHB, socio-economic status (pro-poor for visits to GP, pro-rich for visits to SD), location (for visits to SD), gender, age (age 60 or greater being a negative factor for visits to GP and a positive factor for visits to SD), chronic diseases, and marital status (being married was a negative factor for visits to GP and a positive factor for visits to SD). There is a need for allowing for endogeneity in examining the impact of PHB, social and demographic factors on visits to GP in a population under universal health insurance. For disadvantaged populations with low SES and those living in peripheral districts, the value of IndPrev is lower than for populations with high SES and living in the center of the country. Examining the impact of these factors, significant differences in the importance and sometimes even in the sign of their influence on visits to different categories of doctors - GP and SD, are found.
NASA Astrophysics Data System (ADS)
Wang, Lizhu; Robertson, Dale M.; Garrison, Paul J.
2007-02-01
We sampled 240 wadeable streams across Wisconsin for different forms of phosphorus and nitrogen, and assemblages of macroinvertebrates and fish to (1) examine how macroinvertebrate and fish measures correlated with the nutrients; (2) quantify relationships between key biological measures and nutrient forms to identify potential threshold levels of nutrients to support nutrient criteria development; and (3) evaluate the importance of nutrients in influencing biological assemblages relative to other physicochemical factors at different spatial scales. Twenty-three of the 35 fish and 18 of the 26 macroinvertebrate measures significantly correlated ( P < 0.05) with at least one nutrient measure. Percentages of carnivorous, intolerant, and omnivorous fishes, index of biotic integrity, and salmonid abundance were fish measures correlated with the most nutrient measures and had the highest correlation coefficients. Percentages of Ephemeroptera-Plecoptera-Trichoptera individuals and taxa, Hilsenhoff biotic index, and mean tolerance value were macroinvertebrate measures that most strongly correlated with the most nutrient measures. Selected biological measures showed clear trends toward degradation as concentrations of phosphorus and nitrogen increased, and some measures showed clear thresholds where biological measures changed drastically with small changes in nutrient concentrations. Our selected environmental factors explained 54% of the variation in the fish assemblages. Of this explained variance, 46% was attributed to catchment and instream habitat, 15% to nutrients, 3% to other water quality measures, and 36% to the interactions among all the environmental variables. Selected environmental factors explained 53% of the variation in macroinvertebrate assemblages. Of this explained variance, 42% was attributed to catchment and instream habitat, 22% to nutrients, 5% to other water quality measures, and 32% to the interactions among all the environmental variables.
Wang, L.; Robertson, Dale M.; Garrison, P.J.
2007-01-01
We sampled 240 wadeable streams across Wisconsin for different forms of phosphorus and nitrogen, and assemblages of macroinvertebrates and fish to (1) examine how macroinvertebrate and fish measures correlated with the nutrients; (2) quantify relationships between key biological measures and nutrient forms to identify potential threshold levels of nutrients to support nutrient criteria development; and (3) evaluate the importance of nutrients in influencing biological assemblages relative to other physicochemical factors at different spatial scales. Twenty-three of the 35 fish and 18 of the 26 macroinvertebrate measures significantly correlated (P < 0.05) with at least one nutrient measure. Percentages of carnivorous, intolerant, and omnivorous fishes, index of biotic integrity, and salmonid abundance were fish measures correlated with the most nutrient measures and had the highest correlation coefficients. Percentages of Ephemeroptera-Plecoptera-Trichoptera individuals and taxa, Hilsenhoff biotic index, and mean tolerance value were macroinvertebrate measures that most strongly correlated with the most nutrient measures. Selected biological measures showed clear trends toward degradation as concentrations of phosphorus and nitrogen increased, and some measures showed clear thresholds where biological measures changed drastically with small changes in nutrient concentrations. Our selected environmental factors explained 54% of the variation in the fish assemblages. Of this explained variance, 46% was attributed to catchment and instream habitat, 15% to nutrients, 3% to other water quality measures, and 36% to the interactions among all the environmental variables. Selected environmental factors explained 53% of the variation in macroinvertebrate assemblages. Of this explained variance, 42% was attributed to catchment and instream habitat, 22% to nutrients, 5% to other water quality measures, and 32% to the interactions among all the environmental variables. ?? 2006 Springer Science+Business Media, Inc.
Environmental factors explain socioeconomic prevalence differences in myopia in 6-year-old children.
Tideman, J Willem L; Polling, Jan Roelof; Hofman, Albert; Jaddoe, Vincent Wv; Mackenbach, Johan P; Klaver, Caroline Cw
2018-02-01
High myopia (≤-6 D) usually has its onset before 10 years of age and can lead to blinding complications later in life. We examined whether differences in myopia prevalences in socioeconomic risk groups could be explained by differences in lifestyle factors. A total of 5711 six-year-old children participating in the prospective population-based birth cohort study Generation R underwent a stepwise ophthalmic examination, which included visual acuity and objective cycloplegic refraction to identify children with myopia (≤-0.5D). Daily activities, ethnicity, factors representing family socioeconomic status and housing were ascertained by questionnaire. Risk assessments of myopia and mediation analyses were performed using logistic regression; attenuation of risks was calculated by bootstrapping. Prevalence of myopia was 2.4% (n=137). Myopic children spent more time indoors and less outdoors than non-myopic children (p<0.01), had lower vitamin D (p=0.01), had a higher body mass index and participated less in sports (p=0.03). Children of non-European descent (OR 2.60; 95% CI 1.84 to 3.68), low maternal education (OR 2.27; 95% CI 1.57 to 3.28) and low family income (OR 2.62; 95% CI 1.8 to 3.74) were more often myopic. Lifestyle factors explained the majority of the increased risk for ethnicity (82%; 95% CI 55 to 120), maternal education (69%; 95% CI 45 to 109) and family socioeconomic status (71%; 95% CI 46 to 104). This study found environmental factors to be strong risk factors for myopia already at the age of 6 years. The myopia prevalence differences in socioeconomic groups were greatly determined by differences in distribution of these environmental risk factors, highlighting the importance of lifestyle adjustments in young children developing myopia. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Chamaillé-Jammes, Simon; Charbonnel, Anaïs; Dray, Stéphane; Madzikanda, Hillary; Fritz, Hervé
2016-01-01
The spatial structuring of populations or communities is an important driver of their functioning and their influence on ecosystems. Identifying the (in)stability of the spatial structure of populations is a first step towards understanding the underlying causes of these structures. Here we studied the relative importance of spatial vs. interannual variability in explaining the patterns of abundance of a large herbivore community (8 species) at waterholes in Hwange National Park (Zimbabwe). We analyzed census data collected over 13 years using multivariate methods. Our results showed that variability in the census data was mostly explained by the spatial structure of the community, as some waterholes had consistently greater herbivore abundance than others. Some temporal variability probably linked to Park-scale migration dependent on annual rainfall was noticeable, however. Once this was accounted for, little temporal variability remained to be explained, suggesting that other factors affecting herbivore abundance over time had a negligible effect at the scale of the study. The extent of spatial and temporal variability in census data was also measured for each species. This study could help in projecting the consequences of surface water management, and more generally presents a methodological framework to simultaneously address the relative importance of spatial vs. temporal effects in driving the distribution of organisms across landscapes.
Chamaillé-Jammes, Simon; Charbonnel, Anaïs; Dray, Stéphane; Madzikanda, Hillary; Fritz, Hervé
2016-01-01
The spatial structuring of populations or communities is an important driver of their functioning and their influence on ecosystems. Identifying the (in)stability of the spatial structure of populations is a first step towards understanding the underlying causes of these structures. Here we studied the relative importance of spatial vs. interannual variability in explaining the patterns of abundance of a large herbivore community (8 species) at waterholes in Hwange National Park (Zimbabwe). We analyzed census data collected over 13 years using multivariate methods. Our results showed that variability in the census data was mostly explained by the spatial structure of the community, as some waterholes had consistently greater herbivore abundance than others. Some temporal variability probably linked to Park-scale migration dependent on annual rainfall was noticeable, however. Once this was accounted for, little temporal variability remained to be explained, suggesting that other factors affecting herbivore abundance over time had a negligible effect at the scale of the study. The extent of spatial and temporal variability in census data was also measured for each species. This study could help in projecting the consequences of surface water management, and more generally presents a methodological framework to simultaneously address the relative importance of spatial vs. temporal effects in driving the distribution of organisms across landscapes. PMID:27074044
Pollard, T M; Steptoe, A; Wardle, J
1998-04-01
The Food Choice Questionnaire (FCQ), which measures the reported importance to a given individual of nine factors underlying food choice, and a food frequency questionnaire, were administered to 241 participants, who were also required to classify their diet as either 'standard', 'low in red meat' or 'vegetarian'. Respondents describing their diet as low in red meat attributed greater importance to health, natural content, weight control and ethical concern in their food choice than did those who described their diets as standard, whereas vegetarians differed significantly from those with a standard diet only on the score for ethical concern. Differences between men and women and between students and non-students in the frequency of consumption of a number of foods were shown to be mediated by differences in the importance attached to FCQ factors. Thus the generally healthier diets of women compared to men appeared to be accounted for by the greater importance attributed by women to weight control, natural content and ethical concerns.
Malomane, Dorcus Kholofelo; Norris, David; Banga, Cuthbert B; Ngambi, Jones W
2014-02-01
Body weight and weight of body parts are of economic importance. It is difficult to directly predict body weight from highly correlated morphological traits through multiple regression. Factor analysis was carried out to examine the relationship between body weight and five linear body measurements (body length, body girth, wing length, shank thickness, and shank length) in South African Venda (VN), Naked neck (NN), and Potchefstroom koekoek (PK) indigenous chicken breeds, with a view to identify those factors that define body conformation. Multiple regression was subsequently performed to predict body weight, using orthogonal traits derived from the factor analysis. Measurements were obtained from 210 chickens, 22 weeks of age, 70 chickens per breed. High correlations were obtained between body weight and all body measurements except for wing length in PK. Two factors extracted after varimax rotation explained 91, 95, and 83% of total variation in VN, NN, and PK, respectively. Factor 1 explained 73, 90, and 64% in VN, NN, and PK, respectively, and was loaded on all body measurements except for wing length in VN and PK. In a multiple regression, these two factors accounted for 72% variation in body weight in VN, while only factor 1 accounted for 83 and 74% variation in body weight in NN and PK, respectively. The two factors could be used to define body size and conformation of these breeds. Factor 1 could predict body weight in all three breeds. Body measurements can be better selected jointly to improve body weight in these breeds.
2014-01-01
Background Development rates of Aedes aegypti are known to vary with respect to many abiotic and biotic factors including temperature, resource availability, and intraspecific competition. The relative importance of these factors and their interactions are not well established across populations. We performed meta-analysis on a dataset of development rate estimates from 49 studies. Results Meta-analytic results indicated that the environmental factor of temperature is sufficient to explain development rate variability in Ae. aegypti. While diet and density may greatly impact other developmental phenotypes, these results suggest that for development rate these factors should never be considered to the exclusion of temperature. The effect of temperature on development rate is not homogenous or constant. The sources of heterogeneity of the effect of temperature are difficult to analyze due to lack of consistent reporting of larval rearing methods. Conclusions Temperature is the most important ecological determinant of development rate in Ae. aegypti, but its effect is heterogeneous. Ignoring this heterogeneity is problematic for models of vector population and vector-borne disease transmission. PMID:24495345
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kolhoff, Arend J., E-mail: akolhoff@eia.nl; Runhaar, Hens A.C., E-mail: H.A.C.Runhaar@uu.nl; Forest and Nature Conservation Policy Group, Wageningen University and Research Centre, Wageningen
In this paper, we aim to better understand the factors that contribute to the substantive performance of EIA systems in low and middle income countries. Substantive performance is defined as the extent to which the EIA process contributes to the EIA objectives for the long term, namely environmental protection or, even more ambitious, sustainable development. We have therefore developed a conceptual model in which we focus on the key actors in the EIA system, the proponent and the EIA authority and their level of ownership as a key capacity to measure their performance, and we distinguish procedural performance and somemore » contextual factors. This conceptual model is then verified and refined for the EIA phase and the EIA follow-up phase (permitting, monitoring and enforcement) by means of 12 case studies from Ghana (four cases) and Georgia (eight cases), both lower–middle income countries. We observe that in most cases the level of substantive performance increases during the EIA phase but drops during the EIA follow-up phase, and as a result only five out of 12 operational cases are in compliance with permit conditions or national environmental standards. We conclude, firstly that ownership of the proponent is the most important factor explaining the level of substantive performance; the higher the proponent's level of ownership the higher the level of substantive performance. The influence of the EIA authority on substantive performance is limited. Secondly, the influence of procedural performance on substantive performance seems less important than expected in the EIA phase but more important during the EIA follow-up phase. In order to improve substantive performance we learned two lessons. Firstly, increasing the proponent's level of ownership seems obvious, but direct change is probably difficult. However, where international finance institutes are involved they can increase ownership. Despite the limited influence of the EIA authority, a proactive strategy of, for example, working together with international finance institutes has a slightly larger influence than a reactive strategy. - Highlights: • Ownership of the proponent is the most important factor explaining the level of substantive performance. • The influence of the EIA authority on substantive performance is limited. • The influence of procedural performance on substantive performance seems less important than expected in the EIA phase but more important during the EIA follow-up phase.« less
Fallahpour, Mandana; Tham, Kerstin; Joghataei, Mohammad Taghi; Jonsson, Hans
2011-04-01
To describe perceived participation and autonomy among a sample of persons with stroke in Iran and to identify different aspects of functioning and contextual factors predicting participation after stroke. A cross-sectional study. A total of 102 persons, between 27 and 75 years of age, diagnosed with first-ever stroke. Participants were assessed for different aspects of functioning, contextual factors and health conditions. Participation was assessed using the Persian version of the Impact on Participation and Autonomy questionnaire. This study demonstrated that the majority of the study population perceived their participation and autonomy to be good to fair in the different domains of their participation, but not with respect to the autonomy outdoors domain. In addition, physical function was found to be the most important variable predicting performance-based participation, whereas mood state was the most important variable predicting social-based participation. The results emphasize the importance of physical function, mood state and access to caregiving services as predictors of participation in everyday life after stroke. Whilst there are two dimensions of participation in this Persian sample of persons with stroke, the factors explaining participation seem to be the same across the cultures.
Social and legal determinants for the marketing of GM products in Poland.
Twardowski, Tomasz; Małyska, Aleksandra
2012-02-15
The development of biotechnology is influenced by many factors unique for a specific region. In Poland the lack of legislative solutions (to facilitate the promotion of the inventions) and the public resistance against certain sectors of biotechnology are significant factors limiting any further development. Although, science and technology are the front runners in any innovation, the significance of social and legal aspects is difficult to overestimate. In our opinion those factors are interconnected and crucial for marketing of innovative products, therefore, we indicate and explain the most important issues restraining the implementation of innovative biotechnology in the context of national specificity in Poland. Copyright © 2011 Elsevier B.V. All rights reserved.
Predicting research use in nursing organizations: a multilevel analysis.
Estabrooks, Carole A; Midodzi, William K; Cummings, Greta G; Wallin, Lars
2007-01-01
No empirical literature was found that explained how organizational context (operationalized as a composite of leadership, culture, and evaluation) influences research utilization. Similarly, no work was found on the interaction of individuals and contextual factors, or the relative importance or contribution of forces at different organizational levels to either such proposed interactions or, ultimately, to research utilization. To determine independent factors that predict research utilization among nurses, taking into account influences at individual nurse, specialty, and hospital levels. Cross-sectional survey data for 4,421 registered nurses in Alberta, Canada were used in a series of multilevel (three levels) modeling analyses to predict research utilization. A multilevel model was developed in MLwiN version 2.0 and used to: (a) estimate simultaneous effects of several predictors and (b) quantify the amount of explained variance in research utilization that could be apportioned to individual, specialty, and hospital levels. There was significant variation in research utilization (p <.05). Factors (remaining in the final model at statistically significant levels) found to predict more research utilization at the three levels of analysis were as follows. At the individual nurse level (Level 1): time spent on the Internet and lower levels of emotional exhaustion. At the specialty level (Level 2): facilitation, nurse-to-nurse collaboration, a higher context (i.e., of nursing culture, leadership, and evaluation), and perceived ability to control policy. At the hospital level (Level 3): only hospital size was significant in the final model. The total variance in research utilization was 1.04, and the intraclass correlations (the percent contribution by contextual factors) were 4% (variance = 0.04, p <.01) at the hospital level and 8% (variance = 0.09, p <.05) at the specialty level. The contribution attributable to individual factors alone was 87% (variance = 0.91, p <.01). Variation in research utilization was explained mainly by differences in individual characteristics, with specialty- and organizational-level factors contributing relatively little by comparison. Among hospital-level factors, hospital size was the only significant determinant of research utilization. Although organizational determinants explained less variance in the model, they were still statistically significant when analyzed alone. These findings suggest that investigations into mechanisms that influence research utilization must address influences at multiple levels of the organization. Such investigations will require careful attention to both methodological and interpretative challenges present when dealing with multiple units of analysis.
Partition of nonionic organic compounds in aquatic systems
Smith, James A.; Witkowski, Patrick J.; Chiou, Cary T.
1988-01-01
In aqueous systems, the distribution of many nonionic organic solutes in soil-sediment, aquatic organisms, and dissolved organic matter can be explained in terms of a partition model. The nonionic organic solute is distributed between water and different organic phases that behave as bulk solvents. Factors such as polarity, composition, and molecular size of the solute and organic phase determine the relative importance of partition to the environmental distribution of the solute. This chapter reviews these factors in the context of a partition model and also examines several environmental applications of the partition model for surface- and ground-water systems.
Private gain and public pain: financing American health care.
Siegel, Bruce; Mead, Holly; Burke, Robert
2008-01-01
Health care spending comprises about 16% of the total United States gross domestic product and continues to rise. This article examines patterns of health care spending and the factors underlying their proportional growth. We examine the "usual suspects" most frequently cited as drivers of health care costs and explain why these may not be as important as they seem. We suggest that the drive for technological advancement, coupled with the entrepreneurial nature of the health care industry, has produced inherently inequitable and unsustainable health care expenditure and growth patterns. Successful health reform will need to address these factors and their consequences.
Factors affecting the quality of life in childhood epilepsy in China.
Yong, L; Chengye, J; Jiong, Q
2006-03-01
To explore the level of, and factors affecting the quality of life (QOL) in childhood epilepsy in China. At the Peking University First Hospital, we consecutively identified 418 parents whose children were with known epilepsy to complete a questionnaire, which included children's demographic characteristics, clinical message of epilepsy, QOL, familial message, parental symptoms of anxiety/depression. Significant (p<0.05) affecting factors of children's quality of life included current educational degree, mental development, age at diagnosis, age at onset, seizure frequency, duration, AED number; parental significant (p<0.05) affecting factors included anxiety, depression and health. On regression analysis, parental anxiety was the most important factor in explaining lower QOL in childhood epilepsy. AEDs, familial economic state, paternal career, seizure frequency were also significant factors. Parental anxiety outweighed the physical factors in determining QOL in childhood epilepsy. Recognition of this will be helpful for professionals to treat disease and improve the QOL of childhood epilepsy.
Zacarias, Antonio Eugenio; Macassa, Gloria; Soares, Joaquim JF; Svanström, Leif; Antai, Diddy
2012-01-01
Background Little knowledge exists in Mozambique and sub-Saharan Africa about the mental health (symptoms of depression, anxiety, and somatization) of women victims and perpetrators of intimate partner violence (IPV) by type of abuse (psychological aggression, physical assault without/with injury, and sexual coercion). This study scrutinizes factors associated with mental health among women victims and perpetrators of IPV over the 12 months prior to the study. Methods and materials Mental health data were analyzed with bivariate and multiple regression methods for 1442 women aged 15–49 years who contacted Forensic Services at Maputo Central Hospital (Maputo City, Mozambique) for IPV victimization between April 1, 2007 and March 31, 2008. Results In bivariate analyses, victims and perpetrators of IPVs scored higher on symptoms of mental health than their unaffected counterparts. Multiple regressions revealed that controlling behaviors, mental health comorbidity, social support, smoking, childhood abuse, sleep difficulties, age, and lack of education were more important in explaining symptoms of mental health than demographics/socioeconomics or life-style factors. Victimization and perpetration across all types of IPV were not associated with symptoms of mental health. Conclusion In our sample, victimization and perpetration were not important factors in explaining mental ill health, contrary to previous findings. More research into the relationship between women’s IPV victimization and perpetration and mental health is warranted as well as the influence of controlling behaviors on mental health. PMID:23071419
Deng, Songqiang; Ke, Tan; Li, Longtai; Cai, Shenwen; Zhou, Yuyue; Liu, Yue; Guo, Limin; Chen, Lanzhou; Zhang, Dayi
2018-06-01
Rhizospheric microbes play important roles in plant growth and heavy metals (HMs) transformation, possessing great potential for the successful phytoremediation of environmental pollutants. In the present study, the rhizosphere of Elsholtzia haichowensis Sun was comprehensively studied to uncover the influence of environmental factors (EFs) on the whole microbial communities including bacteria, fungi and archaea, via quantitative polymerase chain reaction (qPCR) and high-throughput sequencing. By analyzing molecular ecological network and multivariate regression trees (MRT), we evaluated the distinct impacts of 37 EFs on soil microbial community. Of them, soil pH, HMs, soil texture and nitrogen were identified as the most influencing factors, and their roles varied across different domains. Soil pH was the main environmental variable on archaeal and bacterial community but not fungi, explaining 25.7%, 46.5% and 40.7% variation of bacterial taxonomic composition, archaeal taxonomic composition and a-diversity, respectively. HMs showed important roles in driving the whole microbial community and explained the major variation in different domains. Nitrogen (NH 4 -N, NO 3 -N, NO 2 -N and TN) explained 47.3% variation of microbial population composition and 15.9% of archaeal taxonomic composition, demonstrating its influence in structuring the rhizospheric microbiome, particularly archaeal and bacterial community. Soil texture accounted for 10.2% variation of population composition, 28.9% of fungal taxonomic composition, 19.2% of fungal a-diversity and 7.8% of archaeal a-diversity. Rhizosphere only showed strong impacts on fungi and bacteria, accounting for 14.7% and 4.9% variation of fungal taxonomic composition and bacterial a-diversity. Spatial distance had stronger influence on bacteria and archaea than fungi, but not as significant as other EFs. For the first time, our study provides a complete insight into key influential EFs on rhizospheric microbes and how their roles vary across microbial domains, giving a hand for understanding the construction of microbial communities in rhizosphere. Copyright © 2017 Elsevier Ltd. All rights reserved.
Key factors affecting urban runoff pollution under cold climatic conditions
NASA Astrophysics Data System (ADS)
Valtanen, Marjo; Sillanpää, Nora; Setälä, Heikki
2015-10-01
Urban runoff contains various pollutants and has the potential of deteriorating the quality of aquatic ecosystems. In this study our objective is to shed light on the factors that control the runoff water quality in urbanized catchments. The effects of runoff event characteristics, land use type and catchment imperviousness on event mass loads (EML) and event mean concentrations (EMC) were studied during warm and cold periods in three study catchments (6.1, 6.5 and 12.6 ha in size) in the city of Lahti, Finland. Runoff and rainfall were measured continuously for two years at each catchment. Runoff samples were taken for total nutrients (tot-P and tot-N), total suspended solids (TSS), heavy metals (Zn, Cr, Al, Co, Ni, Cu, Pb, Mn) and total organic carbon (TOC). Stepwise multiple linear regression analysis (SMLR) was used to identify general relationships between the following variables: event water quality, runoff event characteristics and catchment characteristics. In general, the studied variables explained 50-90% of the EMLs but only 30-60% of the EMCs, with runoff duration having an important role in most of the SMLR models. Mean runoff intensity or peak flow was also often included in the runoff quality models. Yet, the importance (being the first, second or third best) and role (negative or positive impact) of the explanatory variables varied between the cold and warm period. Land use type often explained cold period concentrations, but imperviousness alone explained EMCs weakly. As for EMLs, the influence of imperviousness and/or land use was season and pollutant dependent. The study suggests that pollutant loads can be - throughout the year - adequately predicted by runoff characteristics given that seasonal differences are taken into account. Although pollutant concentrations were sensitive to variation in seasonal and catchment conditions as well, the accurate estimation of EMCs would require a more complete set of explanatory factors than used in this study.
Psychological distress and work and home roles: a focus on socio-economic differences in distress.
Matthews, S; Power, C; Stansfeld, S A
2001-05-01
Home and work factors have been linked to psychological status, but less is known about their contribution to social inequalities in psychological status. We examine whether social inequalities in psychological distress can be explained by work-home factors and whether the impact of these potential explanatory factors is similar for men and women. Data are from the 1958 British birth cohort study. We sought to explain social class differences in psychological distress at age 33. Explanatory factors were classified as work-home roles: i.e. employment, marital status, domestic responsibility, children and elderly care; and work-home characteristics: i.e. job-strain, insecurity, unsocial working hours, youngest child's age, number of children and level of involvement in childcare. A social gradient in psychological distress was found: odds ratios for classes IV and V v. I and II were 2.65 (men) and 3.02 (women). Work factors had consistently stronger associations with psychological distress and with social class among men than women. Work factors had a greater impact on class differences in psychological distress in men. Associations for home roles and characteristics were less consistent and their combined effect on class differences in distress was negligible for both sexes. Explanations for the social gradient differ for men and women. Work may be more important for men than women, but the impact of home factors was not strong during the early adulthood of this cohort.
ERIC Educational Resources Information Center
Aslan, Berna
2015-01-01
Problem Statement: Teacher self-efficacy is important factor for school and student success. This study investigates the variables that explain teacher self-efficacy in Turkey and South Korea according to TALIS 2008 data. A detailed comparison was conducted and the state of the teaching profession in both countries is discussed. Purpose of the…
Our Appetite for Information: Invented Environment, Non-Transparent Mind, and Evolved Preferences
NASA Astrophysics Data System (ADS)
Uhl, Matthias
Evolution and its shaping of our minds are in part responsible for our interest in the media, especially its fictional content. This statement does not mean that everything in the media and fictional plots can be explained on a biological basis. The two other important ingredients are of course the socialization of the individual and the culture it takes place in. The three factors interact.
Krantz, G.; Garcia-Moreno, C.
2005-01-01
Violence against women is now well recognised as a public health problem and human rights violation of worldwide significance. It is an important risk factor for women's ill health, with far reaching consequences for both their physical and mental health. This glossary aims to describe various forms of interpersonal violence that are directed towards women and girls. Terms and basic concepts used in research and policy on this public health problem will be explained. PMID:16166351
Emerging technologies and corporate culture at Microsoft: a methodological note.
Klein, David; Schmeling, James; Blanck, Peter
2005-01-01
This article explores factors important in the study and examination of corporate culture and change. The particular focus is on the technological methods used to conduct a study of accessible technology and corporate culture at Microsoft Corporation. Reasons for particular approaches are explained. Advantages and challenges of emerging technologies that store and retrieve information in the study of corporate culture are reviewed. 2005 John Wiley & Sons, Ltd.
Cockpit Resource Management Proficiency as a Factor of Primary Flight Training
1992-07-01
Cockpit Resource Management ( CRM ). CRM attempts to explain and address the need and importance of "the communication process in the cockpit, and an...6 Definition of Terms Cockpit Resource Management ( CRM ) : The effective use and coordination of all skills and resources- hardware, software, liveware...E. & Williams K. R. (1987). The Application of CRM to Military Operations. In: Cockpit Resource Management Training-NASA Conference’Publication 2455
Does geography or ecology best explain 'cultural' variation among chimpanzee communities?
Kamilar, Jason M; Marshack, Joshua L
2012-02-01
Much attention has been paid to geographic variation in chimpanzee behavior, but few studies have applied quantitative techniques to explain this variation. Here, we apply methods typically utilized in macroecology to explain variation in the putative cultural traits of chimpanzees. We analyzed published data containing 39 behavioral traits from nine chimpanzee communities. We used a canonical correspondence analysis to examine the relative importance of environmental characteristics and geography, which may be a proxy for inter-community gene flow and/or social transmission, for explaining geographic variation in chimpanzee behavior. We found that geography, and longitude in particular, was the best predictor of behavioral variation. Chimpanzee communities in close longitudinal proximity to each other exhibit similar behavioral repertoires, independent of local ecological factors. No ecological variables were significantly related to behavioral variation. These results support the idea that inter-community dispersal patterns have played a major role in structuring behavioral variation. We cannot be certain whether behavioral variation has a genetic basis, is the result of innovation and diffusion, or a combination of the two. Copyright © 2011 Elsevier Ltd. All rights reserved.
Explaining Racial Disparities in Infant Health in Brazil
Nyarko, Kwame A.; Lopez-Camelo, Jorge; Castilla, Eduardo E.
2015-01-01
Objectives. We sought to quantify how socioeconomic, health care, demographic, and geographic effects explain racial disparities in low birth weight (LBW) and preterm birth (PTB) rates in Brazil. Methods. We employed a sample of 8949 infants born between 1995 and 2009 in 15 cities and 7 provinces in Brazil. We focused on disparities in LBW (< 2500 g) and PTB (< 37 gestational weeks) prevalence between infants of African ancestry alone or African mixed with other ancestries, and European ancestry alone. We used a decomposition model to quantify the contributions of conceptually relevant factors to these disparities. Results. The model explained 45% to 94% of LBW and 64% to 94% of PTB disparities between the African ancestry groups and European ancestry. Differences in prenatal care use and geographic location were the most important contributors, followed by socioeconomic differences. The model explained the majority of the disparities for mixed African ancestry and part of the disparity for African ancestry alone. Conclusions. Public policies to improve children’s health should target prenatal care and geographic location differences to reduce health disparities between infants of African and European ancestries in Brazil. PMID:26313046
Explaining Racial Disparities in Infant Health in Brazil
Nyarko, Kwame A.; Lopez-Camelo, Jorge; Castilla, Eduardo E.
2013-01-01
Objectives. We sought to quantify how socioeconomic, health care, demographic, and geographic effects explain racial disparities in low birth weight (LBW) and preterm birth (PTB) rates in Brazil. Methods. We employed a sample of 8949 infants born between 1995 and 2009 in 15 cities and 7 provinces in Brazil. We focused on disparities in LBW (< 2500 g) and PTB (< 37 gestational weeks) prevalence between infants of African ancestry alone or African mixed with other ancestries, and European ancestry alone. We used a decomposition model to quantify the contributions of conceptually relevant factors to these disparities. Results. The model explained 45% to 94% of LBW and 64% to 94% of PTB disparities between the African ancestry groups and European ancestry. Differences in prenatal care use and geographic location were the most important contributors, followed by socioeconomic differences. The model explained the majority of the disparities for mixed African ancestry and part of the disparity for African ancestry alone. Conclusions. Public policies to improve children’s health should target prenatal care and geographic location differences to reduce health disparities between infants of African and European ancestries in Brazil. PMID:23409894
The Role of Climate Covariability on Crop Yields in the Conterminous United States
Leng, Guoyong; Zhang, Xuesong; Huang, Maoyi; ...
2016-09-12
The covariability of temperature (T), precipitation (P) and radiation (R) is an important aspect in understanding the climate influence on crop yields. Here in this paper, we analyze county-level corn and soybean yields and observed climate for the period 1983–2012 to understand how growing-season (June, July and August) mean T, P and R influence crop yields jointly and in isolation across the CONterminous United States (CONUS). Results show that nationally averaged corn and soybean yields exhibit large interannual variability of 21% and 22%, of which 35% and 32% can be significantly explained by T and P, respectively. By including R,more » an additional of 5% in variability can be explained for both crops. Using partial regression analyses, we find that studies that ignore the covariability among T, P, and R can substantially overestimate the sensitivity of crop yields to a single climate factor at the county scale. Further analyses indicate large spatial variation in the relative contributions of different climate variables to the variability of historical corn and soybean yields. Finally, the structure of the dominant climate factors did not change substantially over 1983–2012, confirming the robustness of the findings, which have important implications for crop yield prediction and crop model validations.« less
Emerging Risk Biomarkers in Cardiovascular Diseases and Disorders
Upadhyay, Ravi Kant
2015-01-01
Present review article highlights various cardiovascular risk prediction biomarkers by incorporating both traditional risk factors to be used as diagnostic markers and recent technologically generated diagnostic and therapeutic markers. This paper explains traditional biomarkers such as lipid profile, glucose, and hormone level and physiological biomarkers based on measurement of levels of important biomolecules such as serum ferritin, triglyceride to HDLp (high density lipoproteins) ratio, lipophorin-cholesterol ratio, lipid-lipophorin ratio, LDL cholesterol level, HDLp and apolipoprotein levels, lipophorins and LTPs ratio, sphingolipids, Omega-3 Index, and ST2 level. In addition, immunohistochemical, oxidative stress, inflammatory, anatomical, imaging, genetic, and therapeutic biomarkers have been explained in detail with their investigational specifications. Many of these biomarkers, alone or in combination, can play important role in prediction of risks, its types, and status of morbidity. As emerging risks are found to be affiliated with minor and microlevel factors and its diagnosis at an earlier stage could find CVD, hence, there is an urgent need of new more authentic, appropriate, and reliable diagnostic and therapeutic markers to confirm disease well in time to start the clinical aid to the patients. Present review aims to discuss new emerging biomarkers that could facilitate more authentic and fast diagnosis of CVDs, HF (heart failures), and various lipid abnormalities and disorders in the future. PMID:25949827
Runemark, Anna; Sagonas, Kostas; Svensson, Erik I
2015-08-01
Although rapid evolution of body size on islands has long been known, the ecological mechanisms behind this island phenomenon remain poorly understood. Diet is an important selective pressure for morphological divergence. Here we investigate if selection for novel diets has contributed to the multiple independent cases of island gigantism in the Skyros wall lizard (Podarcis gaigeae) and if diet, predation, or both factors best explain island gigantism. We combined data on body size, shape, bite force, and realized and available diets to address this. Several lines of evidence suggest that diet has contributed to the island gigantism. The larger islet lizards have relatively wider heads and higher bite performance in relation to mainland lizards than would be expected from size differences alone. The proportions of consumed and available hard prey are higher on islets than mainland localities, and lizard body size is significantly correlated with the proportion of hard prey. Furthermore, the main axis of divergence in head shape is significantly correlated with dietary divergence. Finally, a model with only diet and one including diet and predation regime explain body size divergence equally well. Our results suggest that diet is an important ecological factor behind insular body size divergence, but could be consistent with an additional role for predation.
Fishing, fast growth and climate variability increase the risk of collapse
Pinsky, Malin L.; Byler, David
2015-01-01
Species around the world have suffered collapses, and a key question is why some populations are more vulnerable than others. Traditional conservation biology and evidence from terrestrial species suggest that slow-growing populations are most at risk, but interactions between climate variability and harvest dynamics may alter or even reverse this pattern. Here, we test this hypothesis globally. We use boosted regression trees to analyse the influences of harvesting, species traits and climate variability on the risk of collapse (decline below a fixed threshold) across 154 marine fish populations around the world. The most important factor explaining collapses was the magnitude of overfishing, while the duration of overfishing best explained long-term depletion. However, fast growth was the next most important risk factor. Fast-growing populations and those in variable environments were especially sensitive to overfishing, and the risk of collapse was more than tripled for fast-growing when compared with slow-growing species that experienced overfishing. We found little evidence that, in the absence of overfishing, climate variability or fast growth rates alone drove population collapse over the last six decades. Expanding efforts to rapidly adjust harvest pressure to account for climate-driven lows in productivity could help to avoid future collapses, particularly among fast-growing species. PMID:26246548
Fishing, fast growth and climate variability increase the risk of collapse.
Pinsky, Malin L; Byler, David
2015-08-22
Species around the world have suffered collapses, and a key question is why some populations are more vulnerable than others. Traditional conservation biology and evidence from terrestrial species suggest that slow-growing populations are most at risk, but interactions between climate variability and harvest dynamics may alter or even reverse this pattern. Here, we test this hypothesis globally. We use boosted regression trees to analyse the influences of harvesting, species traits and climate variability on the risk of collapse (decline below a fixed threshold) across 154 marine fish populations around the world. The most important factor explaining collapses was the magnitude of overfishing, while the duration of overfishing best explained long-term depletion. However, fast growth was the next most important risk factor. Fast-growing populations and those in variable environments were especially sensitive to overfishing, and the risk of collapse was more than tripled for fast-growing when compared with slow-growing species that experienced overfishing. We found little evidence that, in the absence of overfishing, climate variability or fast growth rates alone drove population collapse over the last six decades. Expanding efforts to rapidly adjust harvest pressure to account for climate-driven lows in productivity could help to avoid future collapses, particularly among fast-growing species. © 2015 The Author(s).
Part of the job: the role of physical work conditions in the nurse turnover process.
Vardaman, James M; Cornell, Paul T; Allen, David G; Gondo, Maria B; Muslin, Ivan S; Mobley, Robin N; Brock, Meagan E; Sigmon, Tracy L
2014-01-01
Retention of nursing staff remains an important issue for health care managers. Turnover research has focused primarily on motivational and social factors as keys to retention, whereas the role of the physical work conditions has received considerably less attention. However, work design theory suggests that physical work conditions may be an important factor in fostering retention among nursing staff. The aim of this study was to integrate work design theory with turnover process models to explore the influence of perceptions of physical work conditions on the development of turnover intentions among nursing staff. Drawing on two samples of registered nurses working in cancer units in metropolitan hospitals in the southeastern United States, this study explores the impact of perceptions of physical work conditions on turnover intentions using ordinary least squares regression. Hypotheses are tested in Study 1 and replicated in Study 2. A measure of perceptions of physical work conditions is also developed and validated using exploratory (Study 1) and confirmatory (Study 2) factor analyses. Perceptions of physical work conditions explain variance in turnover intentions above than that explained by motivational and social factors. Specifically, employee perceptions of noisy work conditions are found to significantly increase turnover intentions, whereas perceptions that work conditions facilitate tasks were found to significantly reduce turnover intentions. Perceptions of temperature and health hazard did not show significant effects. Results suggest that health care managers and scholars should re-examine the role of physical work conditions in the turnover process. Investments in upgrades that facilitate tasks may foster retention better than investments that simply improve employee comfort. Negative perceptions of work conditions may have no impact if they are considered a normal "part of the job," although negative perceptions of conditions that are viewed as under the organization's control may be important in creating a desire to leave.
Burd, Brenda J.; Macdonald, Tara A.; van Roodselaar, Albert
2012-01-01
Detailed knowledge of environmental conditions is required to understand faunal production in coastal seas with topographic and hydrographic complexity. We test the hypothesis that organic biomass and production of subtidal sediment invertebrates throughout the Strait of Georgia, west coast of Canada, can be predicted by depth, substrate type and organic flux modified to reflect lability and age of material. A basin-wide database of biological, geochemical and flux data was analysed using an empirical production/biomass (P/B) model to test this hypothesis. This analysis is unique in the spatial extent and detail of P/B and concurrent environmental measurements over a temperate coastal region. Modified organic flux was the most important predictor of organic biomass and production. Depth and substrate type were secondary modifiers. Between 69–74% of variability in biomass and production could be explained by the combined environmental factors. Organisms <1 mm were important contributors to biomass and production primarily in shallow, sandy sediments, where high P/B values were found despite low organic flux. Low biomass, production, and P/B values were found in the deep, northern basin and mainland fjords, which had silty sediments, low organic flux, low biomass of organisms <1 mm, and dominance by large, slow-growing macrofauna. In the highest organic flux and biomass areas near the Fraser River discharge, production did not increase beyond moderate flux levels. Although highly productive, this area had low P/B. Clearly, food input is insufficient to explain the complex patterns in faunal production revealed here. Additional environmental factors (depth, substrate type and unmeasured factors) are important modifiers of these patterns. Potential reasons for the above patterns are explored, along with a discussion of unmeasured factors possibly responsible for unexplained (30%) variance in biomass and production. We now have the tools for basin-wide first-order estimates of sediment invertebrate production. PMID:22792267
Risk and protective factors for suicidal ideation among Taiwanese adolescents.
Wang, Ruey-Hsia; Lai, Hsiao-Jung; Hsu, Hsiu-Yueh; Hsu, Min-Tao
2011-01-01
: Suicide is the ninth leading cause of death in adolescents aged 15-19 years in Taiwan. Suicidal ideation is an important predictor of committing suicide among adolescents. : The aim of this study was to examine the important risk factors, the protective factors, and the role of protective factors on the relationship of risk factors to suicidal ideation among Taiwanese adolescents aged 15-19 years. : By adopting a cross-sectional study, senior high school students (n = 577) aged 15-19 years in southern Taiwan were recruited for this study. An anonymous self-reported questionnaire was used to collect demographic characteristics, risk factors, protective factors, and suicidal ideation of the sample. Hierarchical logistic regression was used to identify the important risk and protective factors and the interaction between risk and protective factors on suicidal ideation. : Nearly 18% (n = 101) of the participants reported having suicidal ideation during the past 12 months. Gender (female; odds ratio [OR] = 4.23), life stress (OR = 1.03), depression (OR = 3.44), peer suicidal ideation (OR = 4.15), and bullying victimization (OR = 1.81) were important risk factors of suicidal ideation among the targeted sample. In addition, self-esteem (OR = 0.92) and emotional adaptation (OR = 0.88) were important protective factors of suicidal ideation. Self-esteem and emotional adaptation were not used to moderate the negative effects of life stress, depression, perceived peer suicidal ideation, and bullying victimization on suicidal ideation. The final model explained 40.6% of the total variance in suicidal ideation and correctly predicted 86.1% of participants with suicidal ideation. : Suicidal ideation prevention programs should be targeted to female adolescents. School-based efforts that provide adolescents with self-esteem enhancement, emotional regulation skills training, positive peer norms for life, coping skills for managing stress and depression, and antibullying programs might help reduce the suicidal ideation of adolescents.
NASA Astrophysics Data System (ADS)
Wyer, Mary
Contemporary research on gender and persistence in undergraduate education in science and engineering has routinely focused on why students leave their majors rather than asking why students stay. This study compared three common ways of measuring persistence-commitment to major, degree aspirations, and commitment to a science or engineering career-and emphasized factors that would encourage students to persist, including positive images of scientists and engineers, positive attitudes toward gender equity in science and engineering, and positive classroom experiences. A survey was administered in classrooms to a total of 285 female and male students enrolled in two required courses for majors. The results indicate that the different measures of persistence were sensitive to different influences but that students' gender did not interact with their images, attitudes, and experiences in predicted ways. The study concludes that an individual student's gender may be a more important factor in explaining why some female students leave their science and engineering majors than in explaining why others stay.
Mulder, Juul; Ter Bogt, Tom F M; Raaijmakers, Quinten A W; Nic Gabhainn, Saoirse; Monshouwer, Karin; Vollebergh, Wilma A M
2010-06-01
Both music preferences and the substance use behavior of peers are important elements in explaining adolescent substance use. The extent to which music preference and peer use overlap in explaining adolescent substance use remains to be determined. A nationally representative sample of 7324 Dutch school-going adolescents (aged 12-16) provided data on music preferences, substance use behaviors and perceived number of peers using substances. Factor analyses showed that preferences for eight music genres factored into four styles: Pop (chart music, Dutch pop), Adult (classical music, jazz), Urban (rap/hiphop, soul/R&B) and Hard (punk/hardcore, techno/hardhouse); substance use was indicated by smoking, drinking, and cannabis use. Structural equation modeling revealed that the relationship between music preference and substance use was either wholly or partially mediated by perceived peer use. Music can model substance use and fans of different types of music may select friends with use patterns that reinforce their own substance use inclinations.
A Successful Multifaceted Trial to Improve Hypertension Control in Primary Care: Why Did it Work?
Margolis, Karen L; Asche, Stephen E; Bergdall, Anna R; Dehmer, Steven P; Maciosek, Michael V; Nyboer, Rachel A; O'Connor, Patrick J; Pawloski, Pamala A; Sperl-Hillen, JoAnn M; Trower, Nicole K; Tucker, Ann D; Green, Beverly B
2015-11-01
It is important to understand which components of successful multifaceted interventions are responsible for study outcomes, since some components may be more important contributors to the intervention effect than others. We conducted a mediation analysis to determine which of seven factors had the greatest effect on change in systolic blood pressure (BP) after 6 months in a trial to improve hypertension control. The study was a preplanned secondary analysis of a cluster-randomized clinical trial. Eight clinics in an integrated health system were randomized to provide usual care to their patients (n = 222), and eight were randomized to provide a telemonitoring intervention (n = 228). Four hundred three of 450 trial participants completing the 6-month follow-up visit were included. Intervention group participants received home BP telemonitors and transmitted measurements to pharmacists, who adjusted medications and provided advice to improve adherence to medications and lifestyle modification via telephone visits. Path analytic models estimated indirect effects of the seven potential mediators of intervention effect (defined as the difference between the intervention and usual care groups in change in systolic BP from baseline to 6 months). The potential mediators were change in home BP monitor use, number of BP medication classes, adherence to BP medications, physical activity, salt intake, alcohol use, and weight. The difference in change in systolic BP was 11.3 mmHg. The multivariable mediation model explained 47 % (5.3 mmHg) of the intervention effect. Nearly all of this was mediated by two factors: an increase in medication treatment intensity (24 %) and increased home BP monitor use (19 %). The other five factors were not significant mediators, although medication adherence and salt intake improved more in the intervention group than in the usual care group. Most of the explained intervention effect was attributable to the combination of self-monitoring and medication intensification. High adherence at baseline and the relatively low intensity of resources directed toward lifestyle change may explain why these factors did not contribute to the improvement in BP.
Duneau, David; Luijckx, Pepijn; Ben-Ami, Frida; Laforsch, Christian; Ebert, Dieter
2011-02-22
Infection processes consist of a sequence of steps, each critical for the interaction between host and parasite. Studies of host-parasite interactions rarely take into account the fact that different steps might be influenced by different factors and might, therefore, make different contributions to shaping coevolution. We designed a new method using the Daphnia magna - Pasteuria ramosa system, one of the rare examples where coevolution has been documented, in order to resolve the steps of the infection and analyse the factors that influence each of them. Using the transparent Daphnia hosts and fluorescently-labelled spores of the bacterium P. ramosa, we identified a sequence of infection steps: encounter between parasite and host; activation of parasite dormant spores; attachment of spores to the host; and parasite proliferation inside the host. The chances of encounter had been shown to depend on host genotype and environment. We tested the role of genetic and environmental factors in the newly described activation and attachment steps. Hosts of different genotypes, gender and species were all able to activate endospores of all parasite clones tested in different environments; suggesting that the activation cue is phylogenetically conserved. We next established that parasite attachment occurs onto the host oesophagus independently of host species, gender and environmental conditions. In contrast to spore activation, attachment depended strongly on the combination of host and parasite genotypes. Our results show that different steps are influenced by different factors. Host-type-independent spore activation suggests that this step can be ruled out as a major factor in Daphnia-Pasteuria coevolution. On the other hand, we show that the attachment step is crucial for the pronounced genetic specificities of this system. We suggest that this one step can explain host population structure and could be a key force behind coevolutionary cycles. We discuss how different steps can explain different aspects of the coevolutionary dynamics of the system: the properties of the attachment step, explaining the rapid evolution of infectivity and the properties of later parasite proliferation explaining the evolution of virulence. Our study underlines the importance of resolving the infection process in order to better understand host-parasite interactions.
Beck, Audrey N.; Finch, Brian K.; Lin, Shih-Fan; Hummer, Robert A.; Masters, Ryan K.
2014-01-01
This paper uses data from the U.S. National Health Interview Surveys (N = 1,513,097) to describe and explain temporal patterns in black-white health disparities with models that simultaneously consider the unique effects of age, period, and cohort. First, we employ cross-classified random effects age–period–cohort (APC) models to document black-white disparities in self-rated health across temporal dimensions. Second, we use decomposition techniques to shed light on the extent to which socio-economic shifts in cohort composition explain the age and period adjusted racial health disparities across successive birth cohorts. Third, we examine the extent to which exogenous conditions at the time of birth help explain the racial disparities across successive cohorts. Results show that black-white disparities are wider among the pre-1935 cohorts for women, falling thereafter; disparities for men exhibit a similar pattern but exhibit narrowing among cohorts born earlier in the century. Differences in socioeconomic composition consistently contribute to racial health disparities across cohorts; notably, marital status differences by race emerge as an increasingly important explanatory factor in more recent cohorts for women whereas employment differences by race emerge as increasingly salient in more recent cohorts for men. Finally, our cohort characteristics models suggest that cohort economic conditions at the time of birth (percent large family, farm or Southern birth) help explain racial disparities in health for both men and women. PMID:24581075
Larsson, Anette; Palstam, Annie; Löfgren, Monika; Ernberg, Malin; Bjersing, Jan; Bileviciute-Ljungar, Indre; Gerdle, Björn; Kosek, Eva; Mannerkorpi, Kaisa
2017-11-21
Resistance exercise results in health benefits in fibromyalgia. The aim of this study was to determine the factors that mediate change in muscle strength in women with fibromyalgia as a result of resistance exercise. Sixty-seven women with fibromyalgia (age range 25-64 years) were included. Tests of muscle strength and questionnaires related to pain, fear avoidance and physical activity were carried out. Multivariable stepwise regression was used to analyse explanatory factors for change and predictors for final values of knee-extension force, elbow-flexion force and hand-grip force. Change in knee-extension force was explained by fear avoidance beliefs about physical activity at baseline, together with change in pain intensity, knee-extension force at baseline, age and body mass index (BMI) (R2=0.40, p = 0.013). Change in elbow-flexion force was explained by pain intensity at baseline, together with baseline fear avoidance beliefs about physical activity, BMI and elbow-flexion force at baseline (R2 = 0.32, p = 0.043). Change in hand-grip force was explained by hand-grip force at baseline, change in pain intensity and baseline fear avoidance (R2 = 0.37, p = 0.009). Final muscle strength was predicted by the same variables as change, except pain. Pain and fear avoidance are important factors to consider in rehabilitation using resistance exercise for women with fibromyalgia.
Narusyte, Jurgita; Ropponen, Annina; Alexanderson, Kristina; Svedberg, Pia
2016-02-01
Previous research indicates that liability to disability pension (DP) due to mental diagnoses is moderately influenced by genetic factors. This study investigates whether genetic contributions to the liability to DP due to mood and neurotic diagnoses overlap with the genetic influences on major depression (MD), generalized anxiety disorder (GAD), or chronic fatigue (CF). A prospective cohort study including 9,985 female twins born in Sweden 1933-1958. The presence of MD, GAD, and CF was assessed by computer-assisted telephone interviews conducted in 1998-2002. Data on DP due to mood and neurotic diagnoses were obtained from nationwide registers for the years 1998-2010. Common genetic and environmental influences on the phenotypes were estimated by applying structural equation modeling. The prevalence of MD/GAD was 30%, CF 8%, and DP due to mood and neurotic diagnoses 3% in 2010. Genetic effects on MD/GAD explained 31% of the total genetic variation in DP, whereas genetic contributions in common with CF were small and not significant. The majority of the total non-shared environmental variance in DP (85%) was explained by the factors that were unique to DP. Large proportions of genetic and non-shared environmental influences in DP due to mood and neurotic diagnoses were not explained by the contributions from MD/GAD or CF. The results suggest that the process leading to DP is complex and influenced by factors other than those related to the disorder underlying DP.
Large-scale distribution patterns of mangrove nematodes: A global meta-analysis.
Brustolin, Marco C; Nagelkerken, Ivan; Fonseca, Gustavo
2018-05-01
Mangroves harbor diverse invertebrate communities, suggesting that macroecological distribution patterns of habitat-forming foundation species drive the associated faunal distribution. Whether these are driven by mangrove biogeography is still ambiguous. For small-bodied taxa, local factors and landscape metrics might be as important as macroecology. We performed a meta-analysis to address the following questions: (1) can richness of mangrove trees explain macroecological patterns of nematode richness? and (2) do local landscape attributes have equal or higher importance than biogeography in structuring nematode richness? Mangrove areas of Caribbean-Southwest Atlantic, Western Indian, Central Indo-Pacific, and Southwest Pacific biogeographic regions. We used random-effects meta-analyses based on natural logarithm of the response ratio (lnRR) to assess the importance of macroecology (i.e., biogeographic regions, latitude, longitude), local factors (i.e., aboveground mangrove biomass and tree richness), and landscape metrics (forest area and shape) in structuring nematode richness from 34 mangroves sites around the world. Latitude, mangrove forest area, and forest shape index explained 19% of the heterogeneity across studies. Richness was higher at low latitudes, closer to the equator. At local scales, richness increased slightly with landscape complexity and decreased with forest shape index. Our results contrast with biogeographic diversity patterns of mangrove-associated taxa. Global-scale nematode diversity may have evolved independently of mangrove tree richness, and diversity of small-bodied metazoans is probably more closely driven by latitude and associated climates, rather than local, landscape, or global biogeographic patterns.
Zhao, Ruiying; Biswas, Asim; Zhou, Yin; Zhou, Yue; Shi, Zhou; Li, Hongyi
2018-06-23
Environmental factors have shown localized and scale-dependent controls over soil organic matter (SOM) distribution in the landscape. Previous studies have explored the relationships between SOM and individual controlling factors; however, few studies have indicated the combined control from multiple environmental factors. In this study, we compared the localized and scale-dependent univariate and multivariate controls of SOM along two long transects (northeast, NE transect and north, N transect) from China. Bivariate wavelet coherence (BWC) between SOM and individual factors and multiple wavelet coherence (MWC) between SOM and factor combinations were calculated. Average wavelet coherence (AWC) and percent area of significant coherence (PASC) were used to assess the relative dominance of individual and a combination of factors to explain SOM variations at different scales and locations. The results showed that (in BWC analysis) mean annual temperature (MAT) with the largest AWC (0.39) and PASC (16.23%) was the dominant factor in explaining SOM variations along the NE transect. The topographic wetness index (TWI) was the dominant factor (AWC = 0.39 and PASC = 20.80%) along the N transect. MWC identified the combination of Slope, net primary production (NPP) and mean annual precipitation (MAP) as the most important combination in explaining SOM variations along the NE transect with a significant increase in AWC and PASC at different scales and locations (e.g. AWC = 0.91 and PASC = 58.03% at all scales). The combination of TWI, NPP and normalized difference vegetation index (NDVI) was the most influential along the N transect (AWC = 0.83 and PASC = 32.68% at all scales). The results indicated that the combined controls of environmental factors on SOM variations at different scales and locations in a large area can be identified by MWC. This is promising for a better understanding of the multivariate controls in SOM variations at larger spatial scales and may improve the capability of digital soil mapping. Copyright © 2018 Elsevier B.V. All rights reserved.
Feletto, Eleonora; Wilson, Laura Kate; Roberts, Alison Sarah; Benrimoj, Shalom Isaac
2010-09-01
Community pharmacy is an industry undergoing a transformation, evolving from a traditional product supply orientation to a business capable of incorporating services. The theoretical framework of organizational flexibility is used to understand how pharmacies' capacity can be built to provide services and identify key areas needing improvement. To determine the needs of pharmacies that were important and the elements requiring improvement when implementing and delivering services. A mail survey of 2006 Australian community pharmacies was used to identify needs for service implementation. A 25-item scale was used to measure the level of importance (importance measure) of the items and the level of improvement (improvement measure) when implementing services. An exploratory factor analysis was conducted to assess the construct validity and reliability. Responses were received from a total of 395 community pharmacies, with 355 usable responses (17.7%). Factor analysis yielded 3 factors on the importance measure, explaining 42.6% of the variance: (1) planning and performance (item loading range 0.749-0.455; Cronbach's alpha 0.806), (2) people and processes (0.829-0.392; 0.713), and (3) service awareness and infrastructure (0.723-0.310; 0.705). For the improvement measure, 46.9% of the variance was explained by 3 factors: (1) planning, performance, and service awareness (0.827-0.447; 0.858), (2) infrastructure (0.900-0.637; 0.822), and (3) people and processes (0.903-0.311; 0.707). The analyses showed that there are gaps in the capacity of community pharmacy that could be addressed through business and management programs. The theoretical framework of organizational flexibility was useful in highlighting the key areas for stimulating change. To effectively implement services and sustain service delivery, more sophisticated planning and performance monitoring systems are required, supported by changes to infrastructure and staff mix. The critical area for policy makers is the speed at which programs can be restructured to include these issues to encourage the widespread implementation of services. Copyright 2010 Elsevier Inc. All rights reserved.
Wang, Ming-Te; Degol, Jessica; Ye, Feifei
2015-01-01
Although young women now obtain higher course grades in math than boys and are just as likely to be enrolled in advanced math courses in high school, females continue to be underrepresented in some Science, Technology, Engineering, and Mathematics (STEM) occupations. This study drew on expectancy-value theory to assess (1) which intellectual and motivational factors in high school predict gender differences in career choices and (2) whether students' motivational beliefs mediated the pathway of gender on STEM career via math achievement by using a national longitudinal sample in the United States. We found that math achievement in 12th grade mediated the association between gender and attainment of a STEM career by the early to mid-thirties. However, math achievement was not the only factor distinguishing gender differences in STEM occupations. Even though math achievement explained career differences between men and women, math task value partially explained the gender differences in STEM career attainment that were attributed to math achievement. The identification of potential factors of women's underrepresentation in STEM will enhance our ability to design intervention programs that are optimally tailored to female needs to impact STEM achievement and occupational choices.
Buzz Factor or Innovation Potential: What Explains Cryptocurrencies’ Returns?
Wang, Sha
2017-01-01
Cryptocurrencies have become increasingly popular since the introduction of bitcoin in 2009. In this paper, we identify factors associated with variations in cryptocurrencies’ market values. In the past, researchers argued that the “buzz” surrounding cryptocurrencies in online media explained their price variations. But this observation obfuscates the notion that cryptocurrencies, unlike fiat currencies, are technologies entailing a true innovation potential. By using, for the first time, a unique measure of innovation potential, we find that the latter is in fact the most important factor associated with increases in cryptocurrency returns. By contrast, we find that the buzz surrounding cryptocurrencies is negatively associated with returns after controlling for a variety of factors, such as supply growth and liquidity. Also interesting is our finding that a cryptocurrency’s association with fraudulent activity is not negatively associated with weekly returns—a result that further qualifies the media’s influence on cryptocurrencies. Finally, we find that an increase in supply is positively associated with weekly returns. Taken together, our findings show that cryptocurrencies do not behave like traditional currencies or commodities—unlike what most prior research has assumed—and depict an industry that is much more mature, and much less speculative, than has been implied by previous accounts. PMID:28085906
Wang, Ming-Te; Degol, Jessica; Ye, Feifei
2015-01-01
Although young women now obtain higher course grades in math than boys and are just as likely to be enrolled in advanced math courses in high school, females continue to be underrepresented in some Science, Technology, Engineering, and Mathematics (STEM) occupations. This study drew on expectancy-value theory to assess (1) which intellectual and motivational factors in high school predict gender differences in career choices and (2) whether students’ motivational beliefs mediated the pathway of gender on STEM career via math achievement by using a national longitudinal sample in the United States. We found that math achievement in 12th grade mediated the association between gender and attainment of a STEM career by the early to mid-thirties. However, math achievement was not the only factor distinguishing gender differences in STEM occupations. Even though math achievement explained career differences between men and women, math task value partially explained the gender differences in STEM career attainment that were attributed to math achievement. The identification of potential factors of women’s underrepresentation in STEM will enhance our ability to design intervention programs that are optimally tailored to female needs to impact STEM achievement and occupational choices. PMID:25741292
Gourgari, Evgenia; Spanakis, Elias; Dobs, Adrian Sandra
2016-01-01
Polycystic ovary syndrome (PCOS) is a syndrome associated with insulin resistance (IR), obesity, infertility, and increased cardiometabolic risk. This is a descriptive review of several mechanisms that can explain the IR among women with PCOS, other risk factors for the development of diabetes, and the screening methods used for the detection of glucose intolerance in women with PCOS. Few mechanisms can explain IR in women with PCOS such as obesity, insulin receptor signaling defects, and inhibition of insulin-mediated glucose uptake in adipocytes. Women with PCOS have additional risk factors for the development of glucose intolerance such as family history of diabetes, use of oral contraceptives, anovulation, and age. The Androgen Society in 2007 and the Endocrine Society in 2013 recommended using oral glucose tolerance test as a screening tool for abnormal glucose tolerance in all women with PCOS. The approach to detection of glucose intolerance among women with PCOS varies among health care providers. Large prospective studies are still needed for the development of guidelines with strong evidence. When assessing risk of future diabetes in women with PCOS, it is important to take into account the method used for screening as well as other risk factors that these women might have. PMID:27570464
Gourgari, Evgenia; Spanakis, Elias; Dobs, Adrian Sandra
2016-01-01
Polycystic ovary syndrome (PCOS) is a syndrome associated with insulin resistance (IR), obesity, infertility, and increased cardiometabolic risk. This is a descriptive review of several mechanisms that can explain the IR among women with PCOS, other risk factors for the development of diabetes, and the screening methods used for the detection of glucose intolerance in women with PCOS. Few mechanisms can explain IR in women with PCOS such as obesity, insulin receptor signaling defects, and inhibition of insulin-mediated glucose uptake in adipocytes. Women with PCOS have additional risk factors for the development of glucose intolerance such as family history of diabetes, use of oral contraceptives, anovulation, and age. The Androgen Society in 2007 and the Endocrine Society in 2013 recommended using oral glucose tolerance test as a screening tool for abnormal glucose tolerance in all women with PCOS. The approach to detection of glucose intolerance among women with PCOS varies among health care providers. Large prospective studies are still needed for the development of guidelines with strong evidence. When assessing risk of future diabetes in women with PCOS, it is important to take into account the method used for screening as well as other risk factors that these women might have.
Dodani, Sunita
2008-01-01
Background: Coronary artery disease (CAD) is the leading cause of mortality and morbidity in the United States (US), and South Asian immigrants (SAIs) have a higher risk of CAD compared to Caucasians. Traditional risk factors may not completely explain high risk, and some of the unknown risk factors need to be explored. This short review is mainly focused on the possible role of dysfunctional high-density lipoprotein (HDL) in causing CAD and presents an overview of available literature on dysfunctional HDL. Discussion: The conventional risk factors, insulin resistance parameters, and metabolic syndrome, although important in predicting CAD risk, may not sufficiently predict risk in SAIs. HDL has antioxidant, antiinflammatory, and antithrombotic properties that contribute to its function as an antiatherogenic agent. Recent Caucasian studies have shown HDL is not only ineffective as an antioxidant but, paradoxically, appears to be prooxidant, and has been found to be associated with CAD. Several causes have been hypothesized for HDL to become dysfunctional, including Apo lipoprotein A-I (Apo A-I) polymorphisms. New risk factors and markers like dysfunctional HDL and genetic polymorphisms may be associated with CAD. Conclusions: More research is required in SAIs to explore associations with CAD and to enhance early detection and prevention of CAD in this high risk group. PMID:19183743
Crystals for astronomical X-ray spectroscopy
NASA Technical Reports Server (NTRS)
Burek, A.
1976-01-01
Crystal spectrometric properties and the factors that affect their measurement are discussed. Theoretical and experimental results on KAP are summarized and theoretical results based on the dynamical theory of X-ray diffraction are given for the acid phthalates as well as for the commonly used planes of ADP, PET and EDDT. Anomalous dispersion is found to be important for understanding the details of crystal Bragg reflection properties at long X-ray wavelengths and some important effects are pointed out. The theory of anomalous dispersion is applied to explain the anomalous reflectivity exhibited by KAP at 23.3 A.
Geomagnetic activity: Dependence on solar wind parameters
NASA Technical Reports Server (NTRS)
Svalgaard, L.
1977-01-01
Current ideas about the interaction between the solar wind and the earth's magnetosphere are reviewed. The solar wind dynamic pressure as well as the influx of interplanetary magnetic field lines are both important for the generation of geomagnetic activity. The influence of the geometry of the situation as well as the variability of the interplanetary magnetic field are both found to be important factors. Semi-annual and universal time variations are discussed as well as the 22-year cycle in geomagnetic activity. All three are found to be explainable by the varying geometry of the interaction. Long term changes in geomagnetic activity are examined.
2014-01-01
Background The epidemiology of New Neonatal Porcine Diarrhoea Syndrome (NNPDS) was studied in four selected herds. A total of 941 new born piglets in 86 litters were evaluated for five consecutive days. NNPDS is a newly emerged syndrome, characterized by diarrhoea within the first week of life, which is un-responsive to antibiotics and not associated with known pathogens. The aetiology behind the syndrome is unknown, and specific risk factors predisposing piglets to develop NNPDS also remain to be determined. The study evaluated sow and piglet-level risk factors for developing NNPDS and described the epidemiologic characteristics within four herds previously diagnosed with the syndrome. NNPDS was defined as diarrhoea at any time-point during the second to fifth day of life. Results NNPDS was observed in a total of 60% (range: 39%-89%) of first parity piglets and 36% (range: 19-65%) of piglets born by mature sows. In total of 26% of piglets had liquid faeces on the day of birth. Approximately half of these piglets developed NNPDS. In the majority of cases (50-70% of cases within herds) symptoms started on the second or third day of life. Piglets in Herd 1 had12.8 times higher probability of developing NNPDS than piglets in Herd 4. First parity piglets had a 4.1 higher probability of developing NNPDS than piglets born by mature sows. Birth weight and faecal consistency on the day of birth were minor risk factors, each significant within one herd. Conclusions The most important factors associated with NNPDS were herd of origin and sow-parity. The reason for one of the herds experiencing a considerably more severe outbreak than the others was not explained by factors addressed in this study. The epidemiological pattern of diarrhoea varied a lot between herds; however, in all herds first parity piglets seemed predisposed. This association may be explained by an infectious background of the syndrome, but further studies are needed to explain this association. PMID:25012922
Eckhoff, Christian; Kvernmo, Siv
2014-06-18
Pain is common in otherwise healthy adolescents. In recent years widespread musculoskeletal pain, in contrast to single site pain, and associating factors has been emphasized. Musculoskeletal pain has not been examined in Arctic indigenous adolescents. The aim of this study was to explore the prevalence of widespread musculoskeletal pain and its association with psychosocial factors, with emphasis on gender- and ethnic differences (Sami vs. non-Sami), and the influence of pain related functional impairment. This is a cross-sectional study based on The Norwegian Arctic Adolescent Health Study; a school-based survey responded by 4,881 10th grade students (RR: 83%) in North Norway, in 2003-2005. 10% were indigenous Sami. Musculoskeletal pain was based on reported pain in the head, shoulder/neck, back and/or arm/knee/leg, measured by the number of pain sites. Linear multiple regression was used for the multivariable analyses. The prevalence of musculoskeletal pain was high, and significantly higher in females. In total, 22.4% reported 3-4 pain sites. We found a strong association between musculoskeletal pain sites and psychosocial problems, with a higher explained variance in those reporting pain related functional impairment and in females. There were no major differences in the prevalence of musculoskeletal pain in Sami and non-Sami, however the associating factors differed somewhat between the indigenous and non-indigenous group. The final multivariable model, for the total sample, explained 21.2% of the variance of musculoskeletal pain. Anxiety/depression symptoms was the dominant factor associated with musculoskeletal pain followed by negative life events and school-related stress. Anxiety/depression, negative life events, and school-related stress were the most important factors associated with musculoskeletal pain, especially in those reporting pain related functional impairment. The most important sociocultural aspect is the finding that the indigenous Sami are not worse off.
Herrmann, Wolfram J; Haarmann, Alexander; Bærheim, Anders
2015-01-01
In Germany, utilization of ambulatory health care is high compared to other countries. Classical models of health care utilization cannot sufficiently explain these differences. The aim of this study was to explore relevant factors which can explain the higher health care utilization in Germany. In this article, we focus on regulations regarding sickness certification as a potential factor. An explorative qualitative study design. We conducted episodic interviews with 20 patients in Germany and 20 patients in Norway and participant observation in four primary care practices each. Additionally, we conducted a context analysis of relevant health care system related factors which emerged during the study. Qualitative data analysis was done by thematic coding in the framework of grounded theory. The need for a sickness certificate was an important reason for encounter in Germany, especially regarding minor illnesses. Sickness certification is a societal topic. GPs play a double role regarding sickness certification, both as the patients' advocate and as an expert witness for social security services. In Norway, longer periods of self-administered sickness certification and more differentiated possibilities of sickness certification have been introduced successfully. Our results point to regulations regarding sickness certification as a relevant factor for higher health care utilization in Germany. In pilot studies, the effect of extended self-certification of sickness and part-time sickness certification should be further assessed. Copyright © 2015. Published by Elsevier GmbH.
Decomposing socioeconomic inequality in child vaccination: results from Ireland.
Doherty, Edel; Walsh, Brendan; O'Neill, Ciaran
2014-06-05
There is limited knowledge of the extent of or factors underlying inequalities in uptake of childhood vaccination in Ireland. This paper aims to measure and decompose socioeconomic inequalities in childhood vaccination in the Republic of Ireland. The analysis was performed using data from the first wave of the Growing Up in Ireland survey, a nationally representative survey of the carers of over 11,000 nine-month old babies collected in 2008 and 2009. Multivariate analysis was conducted to explore the child and parental factors, including socioeconomic factors that were associated with non-vaccination of children. A concentration index was calculated to measure inequality in childhood vaccination. Subsequent decomposition analysis identified key factors underpinning observed inequalities. Overall the results confirm a strong socioeconomic gradient in childhood vaccination in the Republic of Ireland. Concentration indices of vaccination (CI=-0.19) show a substantial pro-rich gradient. Results from the decomposition analysis suggest that a substantial proportion of the inequality is explained by household level variables such as socioeconomic status, household structure, income and entitlement to publicly funded care (29.9%, 24% 30.6% and 12.9% respectively). Substantial differences are also observed between children of Irish mothers and immigrant mothers from developing countries. Vaccination was less likely in lower than in higher income households. Access to publicly funded services was an important factor in explaining inequalities. Copyright © 2014 Elsevier Ltd. All rights reserved.
Exploring Individual Differences in Online Addictions: the Role of Identity and Attachment.
Monacis, Lucia; de Palo, Valeria; Griffiths, Mark D; Sinatra, Maria
2017-01-01
Research examining the development of online addictions has grown greatly over the last decade with many studies suggesting both risk factors and protective factors. In an attempt to integrate the theories of attachment and identity formation, the present study investigated the extent to which identity styles and attachment orientations account for three types of online addiction (i.e., internet addiction, online gaming addiction, and social media addiction). The sample comprised 712 Italian students (381 males and 331 females) recruited from schools and universities who completed an offline self-report questionnaire. The findings showed that addictions to the internet, online gaming, and social media were interrelated and were predicted by common underlying risk and protective factors. Among identity styles, 'informational' and 'diffuse-avoidant' styles were risk factors, whereas 'normative' style was a protective factor. Among attachment dimensions, the 'secure' attachment orientation negatively predicted the three online addictions, and a different pattern of causal relationships were observed between the styles underlying 'anxious' and 'avoidant' attachment orientations. Hierarchical multiple regressions demonstrated that identity styles explained between 21.2 and 30% of the variance in online addictions, whereas attachment styles incrementally explained between 9.2 and 14% of the variance in the scores on the three addiction scales. These findings highlight the important role played by identity formation in the development of online addictions.
Does personality affect health-related quality of life? A systematic review
Huang, I-Chan; Lee, Joy L.; Ketheeswaran, Pavinarmatha; Jones, Conor M.; Revicki, Dennis A.; Wu, Albert W.
2017-01-01
Background Health-related quality of life (HRQOL) is increasingly measured as an outcome for clinical and health services research. However, relatively little is known about how non-health factors affect HRQOL. Personality is a potentially important factor, yet evidence regarding the effects of personality on HRQOL measures is unclear. Methods This systematic review examined the relationships among aspects of personality and HRQOL. Eligible studies were identified from Medline and PsycINFO. The review included 76 English-language studies with HRQOL as a primary outcome and that assessed personality from the psychological perspective. Individuals with various health states, including ill (e.g., cancer, cardiovascular disorders), aging, and healthy, were included in this review study. Results Some personality characteristics were consistently related to psychosocial aspects more often than physical aspects of HRQOL. Personality characteristics, especially neuroticism, mastery, optimism, and sense of coherence were most likely to be associated with psychosocial HRQOL. Personality explained varying proportions of variance in different domains of HRQOL. The range of variance explained in psychosocial HRQOL was 0 to 45% and the range of explained variance in physical HRQOL was 0 to 39%. Conclusions Personality characteristics are related to HRQOL. Systematic collection and analysis of personality data alongside HRQOL measures may be helpful in medical research, clinical practice, and health policy evaluation. PMID:28355244
van Dongen, Josanne D M; Buck, Nicole M L; van Marle, Hjalmar J C
2016-03-30
It is still not clear what the unique contribution of particular psychopathological factors is in explaining aggression in schizophrenia. The current study examined whether persecutory ideations, psychopathy and substance use are associated with different measures of aggressive behavior. We expected that persecutory ideations are associated with reactive aggression, and psychopathic traits are more associated with proactive aggression of inpatients. 59 inpatients with schizophrenia were included. Persecutory ideations we assessed using the Persecutory Ideation Questionnaire (PIQ), psychopathic traits with the revised version of Psychopathic Personality Inventory (PPI-R) and substance use was assessed using the Comprehensive Assessment of Symptoms and History (CASH). In addition, aggression was measured with the Reactive and Proactive Aggression Questionnaire (RPQ), in an experimental task using the Point Subtraction Aggression Paradigm (PSAP) and on the ward using the Social Dysfunction and Aggression Scale (SDAS). Results showed that psychopathy explains most of the variance in self-reported proactive and reactive aggression. In contrast, persecutory ideations explain most of the variance in observed aggression on the ward. Results implicate that it is important to acknowledge comorbid factors in patients with schizophrenia for more precise risk assessment and appropriate treatment for aggressive patients with schizophrenia. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Moat, K A; Abelson, J
2011-12-01
During the 2001 election campaign, President Yoweri Museveni announced he was abolishing user fees for health services in Uganda. No analysis has been carried out to explain how he was able to initiate such an important policy decision without encountering any immediate barriers. To explain this outcome through in-depth policy analysis driven by the application of key analytical frameworks. An explanatory case study informed by analytical frameworks from the institutionalism literature was undertaken. Multiple data sources were used including: academic literature, key government documents, grey literature, and a variety of print media. According to the analytical frameworks employed, several formal institutional constraints existed that would have reduced the prospects for the abolition of user fees. However, prevalent informal institutions such as "Big Man" presidentialism and clientelism that were both 'competing' and 'complementary' can be used to explain the policy outcome. The analysis suggests that these factors trumped the impact of more formal institutional structures in the Ugandan context. Consideration should be given to the interactions between formal and informal institutions in the analysis of health policy processes in Uganda, as they provide a more nuanced understanding of how each set of factors influence policy outcomes.
Explaining feast or famine in randomized field trials. Medical science and criminology compared.
Shepherd, Jonathan P
2003-06-01
A feast of randomized controlled trials (RCTs) in medical science and comparative famine in criminology can be explained in terms of cultural and structural factors. Of central importance is the context in which the evaluation of interventions is done and the difference in status of situational research in the two disciplines. Evaluation of medical interventions has traditionally been led by practitioner (clinical) academics. This is not the case in criminal justice, where theory has had higher status than intervention research. Medical science has advanced in, or closely associated with, university teaching hospitals, but links between criminology and criminal justice services are far more tenuous. The late development of situational crime prevention seems extraordinary from a medical perspective, as does the absence of university police schools in the United Kingdom and elsewhere. These structural and cultural factors explain concentration of expectation, resource, and RCT productivity in medical science. The Campbell Collaboration and the Academy of Experimental Criminology are forces which are reducing this polarization of feast and famine in RCTs. But unless scientific criminology is embedded in university schools which are responsible for the education and training of law, probation, and police practitioners, convergence in terms of RCTs and implementation of findings in practice seems unlikely.
NASA Astrophysics Data System (ADS)
van der Kooij, Jeroen; Scott, Beth E.; Mackinson, Steven
2008-10-01
Spring distribution and abundance of lesser sandeels during the day were linked to zooplankton densities, seabed substrate and various hydrographic factors using small scale empirical data collected in two areas on the Dogger Bank in 2004, 2005 and 2006. The results of a two-step generalized additive model (GAM) suggested that suitable seabed substrate and temperature best explain sandeel distribution (presence/absence) and that sandeel abundance (given presence) was best described by a model that included bottom temperature, difference between surface and bottom temperature and surface salinity. The current study suggests that suitable seabed substrate explains sandeel distribution in the water column. Bottom temperature and surface salinity also played an important role in explaining distribution and abundance, and we speculate that sandeels favour hydrographically dynamic areas. Contrary to our hypothesis sandeels were not strongly associated with areas of high zooplankton density. We speculate that in early spring on the western Dogger Bank plankton is still patchily distributed and that sandeels only emerge from the seabed when feeding conditions near their night-time burrowing habitat are optimal. The results also suggested that when abundance is over a threshold level, the number of sandeel schools increased rather than the schools becoming bigger. This relationship between patchiness and abundance has implications for mortality rates and hence fisheries management.
3-D reservoir characterization of the House Creek oil field, Powder River Basin, Wyoming
Higley, Debra K.; Pantea, Michael P.; Slatt, Roger M.
1997-01-01
This CD-ROM is intended to serve a broad audience. An important purpose is to explain geologic and geochemical factors that control petroleum production from the House Creek Field. This information may serve as an analog for other marine-ridge sandstone reservoirs. The 3-D slide and movie images are tied to explanations and 2-D geologic and geochemical images to visualize geologic structures in three dimensions, explain the geologic significance of porosity/permeability distribution across the sandstone bodies, and tie this to petroleum production characteristics in the oil field. Movies, text, images including scanning electron photomicrographs (SEM), thin-section photomicrographs, and data files can be copied from the CD-ROM for use in external mapping, statistical, and other applications.
Consumer's Online Shopping Influence Factors and Decision-Making Model
NASA Astrophysics Data System (ADS)
Yan, Xiangbin; Dai, Shiliang
Previous research on online consumer behavior has mostly been confined to the perceived risk which is used to explain those barriers for purchasing online. However, perceived benefit is another important factor which influences consumers’ decision when shopping online. As a result, an integrated consumer online shopping decision-making model is developed which contains three elements—Consumer, Product, and Web Site. This model proposed relative factors which influence the consumers’ intention during the online shopping progress, and divided them into two different dimensions—mentally level and material level. We tested those factors with surveys, from both online volunteers and offline paper surveys with more than 200 samples. With the help of SEM, the experimental results show that the proposed model and method can be used to analyze consumer’s online shopping decision-making process effectively.
Franche, Renée-Louise; Murray, Eleanor; Ibrahim, Selahadin; Smith, Peter; Carnide, Nancy; Côté, Pierre; Gibson, Jane; Koehoorn, Mieke
2011-08-01
To evaluate the impact of worker and workplace factors and of their relationships on work absence duration. Structural equation modeling of 11,762 female, Canadian nurses from the 2005 National Survey of the Work and Health of Nurses. Worker and workplace factors were associated with prolonged work absence. Key proximal predictors were pain-related work interference, depression, pain severity, and respect and support at work. More distal predictors were multimorbidity, abuse at work, and organizational culture. Worker health and workplace factors are important in explaining work absence duration. Self-management for pain and mood, adapted to the work context, may be useful for nurses with chronic pain or depression. Policy makers and administrators should focus on creating respect and support at work, and improving organizational culture.
Dezmirean, Daniel S.
2018-01-01
Diabetes is a metabolic disorder with multifactorial and heterogeneous etiologies. Two types of diabetes are common among humans: type 1 diabetes that occurs when the immune system attacks and destroys insulin and type 2 diabetes, the most common form, that may be caused by several factors, the most important being lifestyle, but also may be determined by different genes. Honey was used in folk medicine for a long time, but the health benefits were explained in the last decades, when the scientific world was concerned in testing and thus explaining the benefits of honey. Different studies demonstrate the hypoglycemic effect of honey, but the mechanism of this effect remains unclear. This review presents the experimental studies completed in the recent years, which support honey as a novel antidiabetic agent that might be of potential significance for the management of diabetes and its complications and also highlights the potential impacts and future perspectives on the use of honey as an antidiabetic agent. PMID:29507651
Decomposition of the drivers of the U.S. hospital spending growth, 2001–2009
2014-01-01
Background United States health care spending rose rapidly in the 2000s, after a period of temporary slowdown in the 1990s. However, the description of the overall trend and the understanding of the underlying drivers of this trend are very limited. This study investigates how well historical hospital cost/revenue drivers explain the recent hospital spending trend in the 2000s, and how important each of these drivers is. Methods We used aggregated time series data to describe the trend in total hospital spending, price, and quantity between 2001 and 2009. We used the Oaxaca-Blinder method to investigate the relative importance of major hospital cost/spending drivers (derived from the literature) in explaining the change in hospital spending patterns between 2001 and 2007. We assembled data from Medicare Cost Reports, American Hospital Association annual surveys, Prospective Payment System (PPS) Impact Files, Medicare Provider Analysis and Review (MedPAR) Medicare claims data, InterStudy reports, National Health Expenditure data, and Area Resource Files. Results Aggregated time series trends show that high hospital spending between 2001 and 2009 appears to be driven by higher payment per unit of hospital output, not by increased utilization. Results using the Oaxaca-Blinder regression decomposition method indicate that changes in historically important spending drivers explain a limited 30% of unit-payment growth, but a higher 60% of utilization growth. Hospital staffing and labor-related costs, casemix, and demographics are the most important drivers of higher hospital revenue, utilization, and unit-payment. Technology is associated with lower utilization, higher unit payment, and limited increases in total revenue. Market competition, primarily because of increased managed care concentration, moderates total revenue growth by driving lower unit payment. Conclusions Much of the rapidly rising hospital spending growth in the 2000s in the United States is driven by factors not commonly known or well measured. Future studies need to explore new factors and dynamics that drive longer-term hospital spending growth in recent years, particularly through the channel of higher prices. PMID:24886580
Pereira, Ana Santos; Dâmaso-Rodrigues, Maria Luísa; Amorim, Ana; Daam, Michiel A; Cerejeira, Maria José
2018-06-16
Studies addressing the predicted effects of pesticides in combination with abiotic and biotic factors on aquatic biota in ditches associated with typical Mediterranean agroecosystems are scarce. The current study aimed to evaluate the predicted effects of pesticides along with environmental factors and biota interactions on macroinvertebrate, zooplankton and phytoplankton community compositions in ditches adjacent to Portuguese maize and tomato crop areas. Data was analysed with the variance partitioning procedure based on redundancy analysis (RDA). The total variance in biological community composition was divided into the variance explained by the multi-substance potentially affected fraction [(msPAF) arthropods and primary producers], environmental factors (water chemistry parameters), biotic interactions, shared variance, and unexplained variance. The total explained variance reached 39.4% and the largest proportion of this explained variance was attributed to msPAF (23.7%). When each group (phytoplankton, zooplankton and macroinvertebrates) was analysed separately, biota interactions and environmental factors explained the largest proportion of variance. Results of this study indicate that besides the presence of pesticide mixtures, environmental factors and biotic interactions also considerably influence field freshwater communities. Subsequently, to increase our understanding of the risk of pesticide mixtures on ecosystem communities in edge-of-field water bodies, variations in environmental and biological factors should also be considered.
Environmental Correlates of Abundances of Mosquito Species and Stages in Discarded Vehicle Tires
YEE, DONALD A.; KNEITEL, JAMIE M.; JULIANO, STEVEN A.
2012-01-01
Discarded vehicle tires are a common habitat for container mosquito larvae, although the environmental factors that may control their presence or abundance within a tire are largely unknown. We sampled discarded vehicle tires in six sites located within four counties of central Illinois during the spring and summer of 2006 to determine associations between a suite of environmental factors and community composition of container mosquitoes. Our goal was to find patterns of association between environmental factors and abundances of early and late instars. We hypothesized that environmental factors correlated with early instars would be indicative of oviposition cues, whereas environmental factors correlated with late instars would be those important for larval survival. We collected 13 species of mosquitoes, with six species (Culex restuans, Cx. pipiens, Aedes albopictus, Cx. salinarius, Ae. atropalpus, and Ae. triseriatus) accounting for ≈95% of all larvae. There were similar associations between congenerics and environmental factors, with Aedes associated with detritus type (fine detritus, leaves, seeds) and Culex associated with factors related to the surrounding habitat (human population density, canopy cover, tire size) or microorganisms (bacteria, protozoans). Although there was some consistency in factors that were important for early and late instar abundance, there were few significant associations between early and late instars for individual species. Lack of correspondence between factors that explain variation in early versus late instars, most notable for Culex, suggests a difference between environmental determinants of oviposition and survival within tires. Environmental factors associated with discarded tires are important for accurate predictions of mosquito occurrence at the generic level. PMID:20180308
Suicidal ideation in ethnic minority and majority adolescents in Utrecht, the Netherlands.
van Bergen, D D; Smit, J H; van Balkom, A J L M; van Ameijden, E; Saharso, S
2008-01-01
We investigated the prevalence and explored the vulnerability to suicidal ideation across several ethnic minority versus ethnic majority adolescents in the city of Utrecht in The Netherlands. Exploratory analyses were conducted on a dataset obtained from the Municipal Health Services in Utrecht. We examined whether ethnic minority adolescents are at risk for suicidal ideation because of a family background of migration, social-economic position and certain family factors, which influence psychological constellations. We found that levels of suicidal ideation among adolescents of Turkish background were significantly higher than in both majority and other minority adolescents, The Turkish adolescents at risk for suicidal ideation reported that they do not enjoy being at home with their families. Psychological factors, in particular lack of self-pride and the idea of not becoming successful in life, appeared to be important, as well as feelings of loneliness. Suicidal ideation was not found equally across all ethnic minority groups. A history of migration, ethnic minority status, or low socioeconomic status were not sufficient to explain the variation across ethnicities. Our results suggest that specific social-cultural factors, contextualized in the individual and located in the family environment, are relevant in explaining the disproportionate rates for Turkish adolescents in Utrecht.
Huttunen, K-L; Mykrä, H; Oksanen, J; Astorga, A; Paavola, R; Muotka, T
2017-05-03
One of the key challenges to understanding patterns of β diversity is to disentangle deterministic patterns from stochastic ones. Stochastic processes may mask the influence of deterministic factors on community dynamics, hindering identification of the mechanisms causing variation in community composition. We studied temporal β diversity (among-year dissimilarity) of macroinvertebrate communities in near-pristine boreal streams across 14 years. To assess whether the observed β diversity deviates from that expected by chance, and to identify processes (deterministic vs. stochastic) through which different explanatory factors affect community variability, we used a null model approach. We observed that at the majority of sites temporal β diversity was low indicating high community stability. When stochastic variation was unaccounted for, connectivity was the only variable explaining temporal β diversity, with weakly connected sites exhibiting higher community variability through time. After accounting for stochastic effects, connectivity lost importance, suggesting that it was related to temporal β diversity via random colonization processes. Instead, β diversity was best explained by in-stream vegetation, community variability decreasing with increasing bryophyte cover. These results highlight the potential of stochastic factors to dampen the influence of deterministic processes, affecting our ability to understand and predict changes in biological communities through time.
Hiscock, Rosemary; Dobbie, Fiona; Bauld, Linda
2015-01-01
Smokers from lower socioeconomic groups are less likely to be successful in stopping smoking than more affluent smokers, even after accessing cessation programmes. Data were analysed from 3057 clients of nine services. Routine monitoring data were expanded with CO validated smoking status at 52-week follow-up. Backwards logistic regression modelling was used to consider which factors were most important in explaining the relationship between SES and quitting. The odds ratio of stopping smoking among more affluent clients, compared with more disadvantaged clients, after taking into account design variables only, was 1.85 (95% CI 1.44 to 2.37) which declined to 1.44 (1.11 to 1.87) when all controls were included. The factors that explained more than 10% of the decline in the odds ratio were age, proportion of friends and family who smoked, nicotine dependence, and taking varenicline. A range of factors contribute to lower cessation rates for disadvantaged smokers. Some of these can be modified by improved smoking cessation service provision, but others require contributions from wider efforts to improve material, human, and social capital. PMID:26273602
A Model of Factors Contributing to STEM Learning and Career Orientation
NASA Astrophysics Data System (ADS)
Nugent, Gwen; Barker, Bradley; Welch, Greg; Grandgenett, Neal; Wu, ChaoRong; Nelson, Carl
2015-05-01
The purpose of this research was to develop and test a model of factors contributing to science, technology, engineering, and mathematics (STEM) learning and career orientation, examining the complex paths and relationships among social, motivational, and instructional factors underlying these outcomes for middle school youth. Social cognitive career theory provided the foundation for the research because of its emphasis on explaining mechanisms which influence both career orientations and academic performance. Key constructs investigated were youth STEM interest, self-efficacy, and career outcome expectancy (consequences of particular actions). The study also investigated the effects of prior knowledge, use of problem-solving learning strategies, and the support and influence of informal educators, family members, and peers. A structural equation model was developed, and structural equation modeling procedures were used to test proposed relationships between these constructs. Results showed that educators, peers, and family-influenced youth STEM interest, which in turn predicted their STEM self-efficacy and career outcome expectancy. STEM career orientation was fostered by youth-expected outcomes for such careers. Results suggest that students' pathways to STEM careers and learning can be largely explained by these constructs, and underscore the importance of youth STEM interest.
Familiarity breeds content: assessing bird species popularity with culturomics
Jepson, Paul R.; Malhado, Ana C. M.; Ladle, Richard J.
2016-01-01
Understanding public perceptions of biodiversity is essential to ensure continued support for conservation efforts. Despite this, insights remain scarce at broader spatial scales, mostly due to a lack of adequate methods for their assessment. The emergence of new technologies with global reach and high levels of participation provide exciting new opportunities to study the public visibility of biodiversity and the factors that drive it. Here, we use a measure of internet saliency to assess the national and international visibility of species within four taxa of Brazilian birds (toucans, hummingbirds, parrots and woodpeckers), and evaluate how much of this visibility can be explained by factors associated with familiarity, aesthetic appeal and conservation interest. Our results strongly indicate that familiarity (human population within the range of a species) is the most important factor driving internet saliency within Brazil, while aesthetic appeal (body size) best explains variation in international saliency. Endemism and conservation status of a species had small, but often negative, effects on either metric of internet saliency. While further studies are needed to evaluate the relationship between internet content and the cultural visibility of different species, our results strongly indicate that internet saliency can be considered as a broad proxy of cultural interest. PMID:26966663
Clostridium botulinum in cattle and dairy products.
Lindström, Miia; Myllykoski, Jan; Sivelä, Seppo; Korkeala, Hannu
2010-04-01
The use of plastic-wrapped and nonacidified silage as cattle feed has led to an increasing number of botulism outbreaks due to Clostridium botulinum Groups I-III in dairy cattle. The involvement of Groups I and II organisms in cattle botulism has raised concern of human botulism risk associated with the consumption of dairy products. Multiplication of C. botulinum in silage and in the gastrointestinal tract of cattle with botulism has been reported, thus contamination of the farm environment and raw milk, and further transmission through the dairy chain, are possible. The standard milk pasteurization treatment does not eliminate spores, and the intrinsic factors of many dairy products allow botulinal growth and toxin production. Although rare, several large botulism outbreaks due to both commercial and home-prepared dairy products have been reported. Factors explaining these outbreaks include most importantly temperature abuse, but also unsafe formulation, inadequate fermentation, insufficient thermal processing, post-process contamination, and lack of adequate quality control for adjunct ingredients were involved. The small number of outbreaks is probably explained by a low incidence of spores in milk, the presence of competitive bacteria in pasteurized milk and other dairy products, and growth-inhibitory combinations of intrinsic and extrinsic factors in cultured and processed dairy products.
Sterud, Tom
2014-07-01
This study aimed to examine gender differences in physician-certified sick leave and the extent to which these differences can be explained by work-related psychosocial and mechanical risk factors. Randomly drawn from the general population in Norway, the cohort comprised working men and women aged 18-69 years (N=12 255, response rate at baseline = 60.9%). Eligible respondents were interviewed in 2009 and registered with an active employee relationship of ≥ 100 actual working days in 2009 and 2010 (N=3688 men and 3070 women). The study measured 11 work-related psychosocial factors and 11 mechanical exposures, and outcomes of interest were physician-certified general sick leave (GSL) >0 days and long-term sick leave (LTSL) ≥ 40 working days during 2010. Women reported a significantly higher level of exposure to 9 of the 11 psychosocial factors evaluated. For mechanical factors, the reporting was mixed. After controlling for age, educational level, sick leave during 2009, housework, working hours and family status, a 1.7-fold risk for GSL and LTSL were found among women. In comparison with the initial model, adjusting for psychosocial factors reduced the excess risk by 21% and 27% for GSL and LTSL, respectively. The total effect of mechanical factors was negligible. Differences between occupations held by women and men explained an additional one-tenth of the excess risk for LTSL among women. Work-related psychosocial factors contributed significantly to a higher level of GSL and LTSL among women. The most important factors were demands for hiding emotions, emotional demands, and effort-payment imbalance.
What explains between-school differences in rates of sexual experience?
Henderson, Marion; Butcher, Isabella; Wight, Daniel; Williamson, Lisa; Raab, Gillian
2008-01-01
Background Schools have the potential to influence their pupils' behaviour through the school's social organisation and culture, as well as through the formal curriculum. This paper provides the first attempt to explain the differences between schools in rates of reported heterosexual sexual experience amongst 15 and 16 year olds. It first examined whether variations in rates of sexual experience remained after controlling for the known predictors of sexual activity. It then examined whether these residuals, or 'school effects', were attributable to processes within the school, or were more likely to reflect characteristics of the neighbourhood. Methods Longitudinal survey data from 4,926 pupils in 24 Scottish schools were linked to qualitative and quantitative data on school processes including quality of relationships (staff-pupil, etc), classroom discipline, organisation of Personal and Social Education, school appearance and pupil morale. Multi-level modelling was used to test a range of models and the resulting 'school effects' were then interpreted using the process data. Results Overall, 42% of girls and 33% of boys reported experience of sexual intercourse, with rates by school ranging from 23% to 61%. When individual socio-economic and socio-cultural factors were taken into account the school variation dropped sharply, though pupils' attitudes and aspirations had little effect. There was very little correlation between boys' and girls' rates of sexual experience by school, after controlling for known predictors of sexual activity. Girls were more influenced by individual socio-economic factors than boys. School-level socio-economic factors were predictive even after taking account of individual socio-cultural factors, suggesting that the wider socio-economic environment further influenced young people's sexual experience. Conclusion Importantly, school processes did not explain the variation between schools in sexual experience. Rather, the variation may have been due to neighbourhood culture. PMID:18261205
Gallina, Alessio; Garland, S Jayne; Wakeling, James M
2018-05-22
In this study, we investigated whether principal component analysis (PCA) and non-negative matrix factorization (NMF) perform similarly for the identification of regional activation within the human vastus medialis. EMG signals from 64 locations over the VM were collected from twelve participants while performing a low-force isometric knee extension. The envelope of the EMG signal of each channel was calculated by low-pass filtering (8 Hz) the monopolar EMG signal after rectification. The data matrix was factorized using PCA and NMF, and up to 5 factors were considered for each algorithm. Association between explained variance, spatial weights and temporal scores between the two algorithms were compared using Pearson correlation. For both PCA and NMF, a single factor explained approximately 70% of the variance of the signal, while two and three factors explained just over 85% or 90%. The variance explained by PCA and NMF was highly comparable (R > 0.99). Spatial weights and temporal scores extracted with non-negative reconstruction of PCA and NMF were highly associated (all p < 0.001, mean R > 0.97). Regional VM activation can be identified using high-density surface EMG and factorization algorithms. Regional activation explains up to 30% of the variance of the signal, as identified through both PCA and NMF. Copyright © 2018 Elsevier Ltd. All rights reserved.
Shi, Yu; Li, Yuntao; Xiang, Xingjia; Sun, Ruibo; Yang, Teng; He, Dan; Zhang, Kaoping; Ni, Yingying; Zhu, Yong-Guan; Adams, Jonathan M; Chu, Haiyan
2018-02-05
The relative importance of stochasticity versus determinism in soil bacterial communities is unclear, as are the possible influences that alter the balance between these. Here, we investigated the influence of spatial scale on the relative role of stochasticity and determinism in agricultural monocultures consisting only of wheat, thereby minimizing the influence of differences in plant species cover and in cultivation/disturbance regime, extending across a wide range of soils and climates of the North China Plain (NCP). We sampled 243 sites across 1092 km and sequenced the 16S rRNA bacterial gene using MiSeq. We hypothesized that determinism would play a relatively stronger role at the broadest scales, due to the strong influence of climate and soil differences in selecting many distinct OTUs of bacteria adapted to the different environments. In order to test the more general applicability of the hypothesis, we also compared with a natural ecosystem on the Tibetan Plateau. Our results revealed that the relative importance of stochasticity vs. determinism did vary with spatial scale, in the direction predicted. On the North China Plain, stochasticity played a dominant role from 150 to 900 km (separation between pairs of sites) and determinism dominated at more than 900 km (broad scale). On the Tibetan Plateau, determinism played a dominant role from 130 to 1200 km and stochasticity dominated at less than 130 km. Among the identifiable deterministic factors, soil pH showed the strongest influence on soil bacterial community structure and diversity across the North China Plain. Together, 23.9% of variation in soil microbial community composition could be explained, with environmental factors accounting for 19.7% and spatial parameters 4.1%. Our findings revealed that (1) stochastic processes are relatively more important on the North China Plain, while deterministic processes are more important on the Tibetan Plateau; (2) soil pH was the major factor in shaping soil bacterial community structure of the North China Plain; and (3) most variation in soil microbial community composition could not be explained with existing environmental and spatial factors. Further studies are needed to dissect the influence of stochastic factors (e.g., mutations or extinctions) on soil microbial community distribution, which might make it easier to predictably manipulate the microbial community to produce better yield and soil sustainability outcomes.
Baert, Isabel A C; Meeus, Mira; Mahmoudian, Armaghan; Luyten, Frank P; Nijs, Jo; Verschueren, Sabine M P
2017-09-01
The aim of this study was to examine the relationship of psychosocial factors, namely, pain catastrophizing, kinesiophobia, and maladaptive coping strategies, with muscle strength, pain, and physical performance in patients with knee osteoarthritis (OA)-related symptoms. A total of 109 women (64 with knee OA-related symptoms) with a mean age of 65.4 years (49-81 years) were recruited for this study. Psychosocial factors were quantified by the Pain Catastrophizing Scale, Tampa Scale for Kinesiophobia, and Pain Coping Inventory. Clinical features were assessed using isometric and isokinetic knee muscle strength measurements, visual analog scale, Western Ontario and McMaster Universities Osteoarthritis Index, and functional tests. Associations were examined using correlation and regression analysis. In knee OA patients, pain catastrophizing, kinesiophobia, and coping strategy explained a significant proportion of the variability in isometric knee extension and flexion strength (6.3%-9.2%), accounting for more overall variability than some demographic and medical status variables combined. Psychosocial factors were not significant independent predictors of isokinetic strength, knee pain, or physical performance. In understanding clinical features related to knee OA, such as muscle weakness, pain catastrophizing, kinesiophobia, and coping strategy might offer something additional beyond what might be explained by traditional factors, underscoring the importance of a biopsychosocial approach in knee OA management. Further research on individual patient characteristics that mediate the effects of psychosocial factors is, however, required in order to create opportunities for more targeted, personalized treatment for knee OA.
Spatial patterns of large natural fires in Sierra Nevada wilderness areas
Collins, B.M.; Kelly, M.; van Wagtendonk, J.W.; Stephens, S.L.
2007-01-01
The effects of fire on vegetation vary based on the properties and amount of existing biomass (or fuel) in a forest stand, weather conditions, and topography. Identifying controls over the spatial patterning of fire-induced vegetation change, or fire severity, is critical in understanding fire as a landscape scale process. We use gridded estimates of fire severity, derived from Landsat ETM+ imagery, to identify the biotic and abiotic factors contributing to the observed spatial patterns of fire severity in two large natural fires. Regression tree analysis indicates the importance of weather, topography, and vegetation variables in explaining fire severity patterns between the two fires. Relative humidity explained the highest proportion of total sum of squares throughout the Hoover fire (Yosemite National Park, 2001). The lowest fire severity corresponded with increased relative humidity. For the Williams fire (Sequoia/Kings Canyon National Parks, 2003) dominant vegetation type explains the highest proportion of sum of squares. Dominant vegetation was also important in determining fire severity throughout the Hoover fire. In both fires, forest stands that were dominated by lodgepole pine (Pinus contorta) burned at highest severity, while red fir (Abies magnifica) stands corresponded with the lowest fire severities. There was evidence in both fires that lower wind speed corresponded with higher fire severity, although the highest fire severity in the Williams fire occurred during increased wind speed. Additionally, in the vegetation types that were associated with lower severity, burn severity was lowest when the time since last fire was fewer than 11 and 17 years for the Williams and Hoover fires, respectively. Based on the factors and patterns identified, managers can anticipate the effects of management ignited and naturally ignited fires at the forest stand and the landscape levels. ?? 2007 Springer Science+Business Media, Inc.
Fellows' in intensive care medicine views on professionalism and how they learn it.
van Mook, Walther N K A; de Grave, Willem S; Gorter, Simone L; Muijtjens, Arno M M; Zwaveling, Jan Harm; Schuwirth, Lambert W; van der Vleuten, Cees P M
2010-02-01
The emphasis on the importance of professionalism in a recent CoBaTrICE-IT paper was impressive. However, insight into the elements of professionalism as perceived relevant for intensivists from the fellows' view, and how these are taught and learned, is limited. A nationwide study was performed in 2007-2008. All ICM fellows (n = 90) were sent a questionnaire containing the following questions regarding training in professionalism (7-point Likert scale (1 = very inadequate, 7 = very adequate)): which are the elements perceived to be important in intensivists'' daily practice (38 items, cat. I)? Which methods of learning and teaching are recognised (16 items, cat. II)? Which methods of teaching and learning are considered especially useful (16 items, cat. III)? Finally, the perceived quantity and quality of formal and informal learning methods, as well as the responsible organisational body was studied. Data were analysed using SPSS 15.0. Response was 75.5 % (n = 68), mean age 34 years. Regarding Elements, scores on virtually all items were high. The factor 'striving for excellence' explained half the variance. Two other aspects, 'Teamwork' and 'Dealing with ethical dilemmas', were identified. Regarding Methods, three dimensions, 'formal curriculum'', 'private and academic experiences' and 'role modelling', proved important. The factor 'formal curriculum' explained most of the variance. Regarding Usefulness the same factors, now mainly explained by the factor Private and academic experiences, emerged with variance. In both categories the items 'observations in daily practice' and 'watching television programmes like ER and House' were the highest- and lowest-scoring items (5.99 and 5.81, and 2.69 and 2.49, respectively). Mean scores regarding the quantity of formal and informal teaching were 4.06 and 4.58 (range 1.841 and 1.519). For the quality of teaching, the figures were 4.22 and 4.52 (range 1.659 and 1.560, respectively). 54 suggestions for improvement of teaching were documented. The need for some form of formal teaching of professionalism aspects as well as for feedback was most frequently mentioned (n = 19 and 16). The local training centres are considered and should remain pivotal for teaching professionalism issues (n = 17 and 28). Almost all elements of professionalism were considered relevant to intensivists' daily practice. Although formal teaching methods regarding professionalism aspects are easily recognised in daily practice, learning by personal experiences and informal ways quantitatively plays a more important, and more valued role. Qualitative comments, nevertheless, stress the need for providing and receiving (solicited and unsolicited) feedback, thereby requesting expansion of formal teaching methods. The local training centres (should continue to) play a major role in teaching professionalism, although an additional role for the (inter)national intensive care organisations remains.
Factors related to the decision of men and women to continue taking science courses in college
NASA Astrophysics Data System (ADS)
Deboer, George E.
The purpose of this study was to determine the importance of the transition between a student's initial collegiate science experience and the decision to continue in science, and whether the reasons students give to explain their success or failure in their first course are related to that decision. Attribution theory provided the framework for investigating these factors. The results showed that for unsuccessful students, the plan to continue in science was unrelated to gender, mathematical aptitude, performance in the first science course, or attributions to luck, effort, ability, or task difficulty. For successful students, the plan to continue in science was directly related to attributions to ability, and inversely related to task difficulty. The results demonstrate the importance of a sense of competence for students who continue in science.
Coleman, Albert M E
2013-11-01
To review physician's attitudes as well as the variables that may impact on physicians' attitude toward advance directives (ADs). Literature review of 17 published articles, covering the period 1989 to 2011. Physicians overall have a positive attitude toward patients' AD. However, other factors affect this "general positive attitude." These factors influence the attitude-behavior relationship of physicians, and hence their actual practice in relation to patients' AD. The findings from this review are of importance in explaining the differences in the attitude of physicians toward AD and their compliance. This raises the issue of consideration of other ethical paradigms/theories in the clinical context other than the framework of "principlism-"based autonomy, on which AD leans on. This is important in light of the pluralism of ethical theories.
Communicating with the public about risk
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wade, C R; Molony, S T; Durbin, M E
1992-01-01
Risk communication is a growing specialty field in communication that draws from well-established principles of sociology and psychology. It is a new way to communicate with potentially hostile audiences about sensitive environmental, safety, and health issues they face. This paper explains the most important principles of risk communication and discusses audience analyses, perceptions of risk (outrage factors), and risk comparisons. These principles are applied to a risk communication issue in Malhuevo, a fictitious Arizona community.
Associations between environmental factors and hospital admissions for sickle cell disease
Piel, Frédéric B.; Tewari, Sanjay; Brousse, Valentine; Analitis, Antonis; Font, Anna; Menzel, Stephan; Chakravorty, Subarna; Thein, Swee Lay; Inusa, Baba; Telfer, Paul; de Montalembert, Mariane; Fuller, Gary W.; Katsouyanni, Klea; Rees, David C.
2017-01-01
Sickle cell disease is an increasing global health burden. This inherited disease is characterized by a remarkable phenotypic heterogeneity, which can only partly be explained by genetic factors. Environmental factors are likely to play an important role but studies of their impact on disease severity are limited and their results are often inconsistent. This study investigated associations between a range of environmental factors and hospital admissions of young patients with sickle cell disease in London and in Paris between 2008 and 2012. Specific analyses were conducted for subgroups of patients with different genotypes and for the main reasons for admissions. Generalized additive models and distributed lag non-linear models were used to assess the magnitude of the associations and to calculate relative risks. Some environmental factors significantly influence the numbers of hospital admissions of children with sickle cell disease, although the associations identified are complicated. Our study suggests that meteorological factors are more likely to be associated with hospital admissions for sickle cell disease than air pollutants. It confirms previous reports of risks associated with wind speed (risk ratio: 1.06/standard deviation; 95% confidence interval: 1.00–1.12) and also with rainfall (1.06/standard deviation; 95% confidence interval: 1.01–1.12). Maximum atmospheric pressure was found to be a protective factor (0.93/standard deviation; 95% confidence interval: 0.88–0.99). Weak or no associations were found with temperature. Divergent associations were identified for different genotypes or reasons for admissions, which could partly explain the lack of consistency in earlier studies. Advice to patients with sickle cell disease usually includes avoiding a range of environmental conditions that are believed to trigger acute complications, including extreme temperatures and high altitudes. Scientific evidence to support such advice is limited and sometimes confusing. This study shows that environmental factors do explain some of the variations in rates of admission to hospital with acute symptoms in sickle cell disease, but the associations are complex, and likely to be specific to different environments and the individual’s exposure to them. Furthermore, this study highlights the need for prospective studies with large numbers of patients and standardized protocols across Europe. PMID:27909222
Associations between environmental factors and hospital admissions for sickle cell disease.
Piel, Frédéric B; Tewari, Sanjay; Brousse, Valentine; Analitis, Antonis; Font, Anna; Menzel, Stephan; Chakravorty, Subarna; Thein, Swee Lay; Inusa, Baba; Telfer, Paul; de Montalembert, Mariane; Fuller, Gary W; Katsouyanni, Klea; Rees, David C
2017-04-01
Sickle cell disease is an increasing global health burden. This inherited disease is characterized by a remarkable phenotypic heterogeneity, which can only partly be explained by genetic factors. Environmental factors are likely to play an important role but studies of their impact on disease severity are limited and their results are often inconsistent. This study investigated associations between a range of environmental factors and hospital admissions of young patients with sickle cell disease in London and in Paris between 2008 and 2012. Specific analyses were conducted for subgroups of patients with different genotypes and for the main reasons for admissions. Generalized additive models and distributed lag non-linear models were used to assess the magnitude of the associations and to calculate relative risks. Some environmental factors significantly influence the numbers of hospital admissions of children with sickle cell disease, although the associations identified are complicated. Our study suggests that meteorological factors are more likely to be associated with hospital admissions for sickle cell disease than air pollutants. It confirms previous reports of risks associated with wind speed (risk ratio: 1.06/standard deviation; 95% confidence interval: 1.00-1.12) and also with rainfall (1.06/standard deviation; 95% confidence interval: 1.01-1.12). Maximum atmospheric pressure was found to be a protective factor (0.93/standard deviation; 95% confidence interval: 0.88-0.99). Weak or no associations were found with temperature. Divergent associations were identified for different genotypes or reasons for admissions, which could partly explain the lack of consistency in earlier studies. Advice to patients with sickle cell disease usually includes avoiding a range of environmental conditions that are believed to trigger acute complications, including extreme temperatures and high altitudes. Scientific evidence to support such advice is limited and sometimes confusing. This study shows that environmental factors do explain some of the variations in rates of admission to hospital with acute symptoms in sickle cell disease, but the associations are complex, and likely to be specific to different environments and the individual's exposure to them. Furthermore, this study highlights the need for prospective studies with large numbers of patients and standardized protocols across Europe. Copyright© Ferrata Storti Foundation.
Contribution of Established Stroke Risk Factors to the Burden of Stroke in Young Adults.
Aigner, Annette; Grittner, Ulrike; Rolfs, Arndt; Norrving, Bo; Siegerink, Bob; Busch, Markus A
2017-07-01
As stroke in young adults is assumed to have different etiologies and risk factors than in older populations, the aim of this study was to examine the contribution of established potentially modifiable cardiovascular risk factors to the burden of stroke in young adults. A German nationwide case-control study based on patients enrolled in the SIFAP1 study (Stroke In Young Fabry Patients) 2007 to 2010 and controls from the population-based GEDA study (German Health Update) 2009 to 2010 was performed. Cases were 2125 consecutive patients aged 18 to 55 years with acute first-ever stroke from 26 clinical stroke centers; controls (age- and sex-matched, n=8500, without previous stroke) were from a nationwide community sample. Adjusted population-attributable risks of 8 risk factors (hypertension, hyperlipidemia, diabetes mellitus, coronary heart disease, smoking, heavy episodic alcohol consumption, low physical activity, and obesity) and their combinations for all stroke, ischemic stroke, and primary intracerebral hemorrhage were calculated. Low physical activity and hypertension were the most important risk factors, accounting for 59.7% (95% confidence interval, 56.3-63.2) and 27.1% (95% confidence interval, 23.6-30.6) of all strokes, respectively. All 8 risk factors combined explained 78.9% (95% confidence interval, 76.3-81.4) of all strokes. Population-attributable risks of all risk factors were similar for all ischemic stroke subtypes. Population-attributable risks of most risk factors were higher in older age groups and in men. Modifiable risk factors previously established in older populations also account for a large part of stroke in younger adults, with 4 risk factors explaining almost 80% of stroke risk. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00414583. © 2017 American Heart Association, Inc.
Adversity magnifies the importance of social information in decision-making.
Pérez-Escudero, Alfonso; de Polavieja, Gonzalo G
2017-11-01
Decision-making theories explain animal behaviour, including human behaviour, as a response to estimations about the environment. In the case of collective behaviour, they have given quantitative predictions of how animals follow the majority option. However, they have so far failed to explain that in some species and contexts social cohesion increases when conditions become more adverse (i.e. individuals choose the majority option with higher probability when the estimated quality of all available options decreases). We have found that this failure is due to modelling simplifications that aided analysis, like low levels of stochasticity or the assumption that only one choice is the correct one. We provide a more general but simple geometric framework to describe optimal or suboptimal decisions in collectives that gives insight into three different mechanisms behind this effect. The three mechanisms have in common that the private information acts as a gain factor to social information: a decrease in the privately estimated quality of all available options increases the impact of social information, even when social information itself remains unchanged. This increase in the importance of social information makes it more likely that agents will follow the majority option. We show that these results quantitatively explain collective behaviour in fish and experiments of social influence in humans. © 2017 The Authors.
Weight Misperceptions and Racial and Ethnic Disparities in Adolescent Female Body Mass Index
Krauss, Ramona C.; Powell, Lisa M.; Wada, Roy
2012-01-01
This paper investigated weight misperceptions as determinants of racial/ethnic disparities in body mass index (BMI) among adolescent females using data from the National Survey of Youth 1997. Compared to their white counterparts, higher proportions of black and Hispanic adolescent females underperceived their weight status; that is, they misperceived themselves to have lower weight status compared to their clinically defined weight status. Compared to their black counterparts, higher proportions of white and Hispanic adolescent females misperceived themselves to be heavier than their clinical weight status. Oaxaca-Blinder decomposition analysis showed that accounting for weight misperceptions, in addition to individual and contextual factors, increased the total explained portion of the black-white female BMI gap from 44.7% to 54.3% but only slightly increased the total explained portion of the Hispanic-white gap from 62.8% to 63.1%. Weight misperceptions explained 13.0% of the black-white female BMI gap and 3.3% of the Hispanic-white female BMI gap. The regression estimates showed that weight underperceptions were important determinants of adolescent female BMI, particularly among black and Hispanic adolescents. Education regarding identification and interpretation of weight status may play an important role to help reduce the incidence and racial disparity of female adolescent obesity. PMID:22701166
[THE ROLE OF ESTROGENS IN THE CARCINOGENESIS OF LUNG CANCER].
Uchikova, E; Uchikov, A; Dimitrakova, E; Uchikov, P
2016-01-01
Morbidity and mortality from lung cancer has dramatically increased in women as compared to men over the past few years. Historically, smoking has been considered the major risk factor for lung cancer regardless of gender. Several recent lines of evidence implicate gender differences in the observed differences in prevalence and histologic type which cannot be explained based on the carcinogenic action of nicotine. Several recent studies underscore the importance of reproductive and hormonal factors in the carcinogenesis of lung cancer Lung cancer morbidity and mortality in Bulgaria was 16.2/100000 women and 14.6/ 100000 women, resp. Lung cancer morbidity in Europe was 39/100000 women. Lung cancer is extremely sensitive to estrogens. The latter act directly or as effect modifiers for the relationship between smoking and lung cancer. Further research examining the relationship between serum estrogen levels and the estrogen receptor expression in normal and tumor lung tissue samples can help elucidate the importance of reproductive and hormonal (exogenous and endogenous) factors in the carcinogenesis of lung cancer.
NASA Astrophysics Data System (ADS)
Plakhotnik, Taras; Reichardt, Jens
2018-03-01
A theoretical framework is presented that permits investigations of the relation between inelastic backscattering from microparticles and bulk samples of Raman-active materials. It is based on the Lorentz reciprocity theorem and no fundamental restrictions concerning the microparticle shape apply. The approach provides a simple and intuitive explanation for the enhancement of the differential backscattering cross-section in particles in comparison to bulk. The enhancement factor for scattering of water droplets in the diameter range from 0 to 60 μm (vitally important for the a priori measurement of liquid water content of warm clouds with spectroscopic Raman lidars) is about a factor of 1.2-1.6 larger (depending on the size of the sphere) than an earlier study has shown. The numerical calculations are extended to 1000 μm and demonstrate that dispersion of the refractive index of water becomes an important factor for spheres larger than 100 μm. The physics of the oscillatory phenomena predicted by the simulations is explained.
Cardiovascular risk in rheumatoid arthritis: assessment, management and next steps
Zegkos, Thomas; Kitas, George; Dimitroulas, Theodoros
2016-01-01
Rheumatoid arthritis (RA) is associated with increased cardiovascular (CV) morbidity and mortality which cannot be fully explained by traditional CV risk factors; cumulative inflammatory burden and antirheumatic medication-related cardiotoxicity seem to be important contributors. Despite the acknowledgment and appreciation of CV disease burden in RA, optimal management of individuals with RA represents a challenging task which remains suboptimal. To address this need, the European League Against Rheumatism (EULAR) published recommendations suggesting the adaptation of traditional risk scores by using a multiplication factor of 1.5 if two of three specific criteria are fulfilled. Such guidance requires proper coordination of several medical specialties, including general practitioners, rheumatologists, cardiologists, exercise physiologists and psychologists to achieve a desirable result. Tight control of disease activity, management of traditional risk factors and lifestyle modification represent, amongst others, the most important steps in improving CV disease outcomes in RA patients. Rather than enumerating studies and guidelines, this review attempts to critically appraise current literature, highlighting future perspectives of CV risk management in RA. PMID:27247635
Barnes, J C; Boutwell, Brian B; Miller, J Mitchell; DeShay, Rashaan A; Beaver, Kevin M; White, Norman
2016-01-01
To examine whether differential exposure to pre- and perinatal risk factors explained differences in levels of self-regulation between children of different races (White, Black, Hispanic, Asian, and Other). Multiple regression models based on data from the Early Childhood Longitudinal Study, Birth Cohort (n ≈ 9,850) were used to analyze the impact of pre- and perinatal risk factors on the development of self-regulation at age 2 years. Racial differences in levels of self-regulation were observed. Racial differences were also observed for 9 of the 12 pre-/perinatal risk factors. Multiple regression analyses revealed that a portion of the racial differences in self-regulation was explained by differential exposure to several of the pre-/perinatal risk factors. Specifically, maternal age at childbirth, gestational timing, and the family's socioeconomic status were significantly related to the child's level of self-regulation. These factors accounted for a statistically significant portion of the racial differences observed in self-regulation. The findings indicate racial differences in self-regulation may be, at least partially, explained by racial differences in exposure to pre- and perinatal risk factors.
Health factors in the everyday life and work of public sector employees in Sweden.
Erlandsson, Lena-Karin; Carlsson, Gunilla; Horstmann, Vibeke; Gard, Gunvor; Holmström, Eva
2012-01-01
The aim was to explore aspects of everyday life in addition to established risk factors and their relationship to subjective health and well-being among public sector employees in Sweden. Gainful employment impact on employees' health and well-being, but work is only one part of everyday life and a broader perspective is essential in order to identify health-related factors. Data were obtained from employees at six Social Insurance Offices in Sweden, 250 women and 50 men. A questionnaire based on established instruments and questions specifically designed for this study was used. Relationships between five factors of everyday life, subjective health and well-being were investigated by means of multivariate logistic regression analysis. The final model revealed a limited importance of certain work-related factors. A general satisfaction with everyday activities, a stress-free environment and general control in addition to not having monotonous movements at work were found to be factors explaining 46.3% of subjective good health and well-being. A person's entire activity pattern, including work, is important, and strategies for promoting health should take into account the person's situation as a whole. The interplay between risk and health factors is not clear and further research is warranted.
Arbour-Nicitopoulos, Kelly P; Martin Ginis, Kathleen A; Wilson, Philip M
2010-05-01
Theory of Planned Behavior (TPB) constructs have been shown to be useful for explaining leisure-time physical activity (LTPA) in persons with spinal cord injury (SCI). However, other factors not captured by the TPB may also be important predictors of LTPA for this population. The purpose of this study is to examine the role of neighborhood perceptions within the context of the TPB for understanding LTPA in persons living with SCI. This is a cross-sectional analysis (n = 574) using structural equation modeling involving measures of the TPB constructs, perceived neighborhood esthetics and sidewalks, and LTPA. TPB constructs explained 57% of the variance in intentions and 12% of the variance in behavior. Inclusion of the neighborhood variables to the model resulted in an additional 1% of the variance explained in intentions, with esthetics exhibiting significant positive relationships with the TPB variables. Integrating perceived neighborhood esthetics into the TPB framework provides additional understanding of LTPA intentions in persons living with SCI.
Arora, Anita; Spatz, Erica; Herrin, Jeph; Riley, Carley; Roy, Brita; Kell, Kenneth; Coberley, Carter; Rula, Elizabeth; Krumholz, Harlan M.
2016-01-01
Geographic disparities in life expectancy are substantial and not fully explained by differences in race and socioeconomic status. To develop policies that address these inequalities, it is essential to identify other factors that account for this variation. In this study we investigated whether population well-being—a comprehensive measure of physical, mental, and social health—helps explain geographic variation in life expectancy. At the county level, we found that for every 1-standarddeviation (4.2-point) increase in the well-being score, life expectancy was 1.9 years higher for females and 2.6 years higher for males. Life expectancy and well-being remained positively associated, even after race, poverty, and education were controlled for. In addition, well-being partially mediated the established associations of race, poverty, and education with life expectancy. These findings highlight well-being as an important metric of a population’s health and longevity and as a promising focus for intervention. PMID:27834249
Political complexity predicts the spread of ethnolinguistic groups
Currie, Thomas E.; Mace, Ruth
2009-01-01
Human languages show a remarkable degree of variation in the area they cover. However, the factors governing the distribution of human cultural groups such as languages are not well understood. While previous studies have examined the role of a number of environmental variables the importance of cultural factors has not been systematically addressed. Here we use a geographical information system (GIS) to integrate information about languages with environmental, ecological, and ethnographic data to test a number of hypotheses that have been proposed to explain the global distribution of languages. We show that the degree of political complexity and type of subsistence strategy exhibited by societies are important predictors of the area covered by a language. Political complexity is also strongly associated with the latitudinal gradient in language area, whereas subsistence strategy is not. We argue that a process of cultural group selection favoring more complex societies may have been important in shaping the present-day global distribution of language diversity. PMID:19380740
THE EDUCATION-HEALTH GRADIENT.
Conti, Gabriella; Heckman, James; Urzua, Sergio
2010-05-01
In this paper, we determine the role played by early cognitive, noncognitive, and health endowments. We identify the causal effect of education on health and health-related behaviors. We develop an empirical model of schooling choice and post-schooling outcomes, where both schooling and the outcomes determined in part by schooling are influenced by measured early family environments and latent capabilities (cognitive, noncognitive and health). We show that family background characteristics, and cognitive, noncognitive, and health endowments developed by age 10, are important determinants of labor market and health disparities at age 30. Not properly accounting for personality traits overestimates the importance of cognitive ability in determining adult health. Selection on factors determined early in life explains more than half of the observed difference by education in poor health, depression, and obesity. Education has an important causal effect in explaining differences in many adult outcomes and healthy behaviors. We uncover significant gender differences. We go beyond the current literature which typically estimates mean effects to compute distributions of treatment effects. We show how the health returns to education can vary among individuals who are similar with respect to their observed characteristics, and how a mean effect can hide gains and losses for different individuals. Our research highlights the important role played by the early years in producing health.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prhavc, M.; Prakash, T.P.; Minasov, G.
Oligonucleotides with a novel, 2'-O-[2-[2-(N,N-dimethylamino)ethoxy]ethyl] (2'-O-DMAEOE) modification have been synthesized. This modification, a cationic analogue of the 2'-O-(2-methoxyethyl) (2'-O-MOE) modification, exhibits high binding affinity to target RNA (but not to DNA) and exceptional resistance to nuclease degradation. Analysis of the crystal structure of a self-complementary oligonucleotide containing a single 2'-O-DMAEOE modification explains the importance of charge factors and gauche effects on the observed antisense properties. 2'-O-DMAEOE modified oligonucleotides are ideal candidates for antisense drugs.
Basson, Mariëtta J; Rothmann, Sebastiaan
2018-04-01
Self-determination theory (SDT) provides a model to improve pharmacy students' well-being or functioning in their study context. According to SDT, students need a context that satisfies their needs for autonomy, relatedness and competence in order to function optimally. Contextual factors that could have an impact on a student's functioning are lecturers, family, peers and workload. To investigate whether there is a difference between the contributions family, lecturers, peers and workload make towards the satisfaction of pharmacy students' basic psychological needs within a university context. An electronic survey was administered amongst students registered with the North-West University's School of Pharmacy. Registered pharmacy students, 779, completed said electronic survey comprised of a questionnaire on demographics, BMPN (Balanced Measure of Psychological Needs) and self-developed ANPNS (Antecedents of Psychological Need-satisfaction Scale). Data derived from the afore-going was analysed with the aid of structural equation modelling (SEM). Structural equation modelling explained 46%, 25% and 30% respectively of the total group's variances in autonomy, competence and relatedness satisfaction, and 26% of the variance in psychological need frustration. Peers and family played a significant role in the satisfaction of students' need for autonomy, relatedness and competence, whilst workload seemingly hampered satisfaction with regards to relatedness and autonomy. Workload contributed towards frustration with regards to psychological need satisfaction. The role played by lecturers in satisfying pharmacy students' need for autonomy, relatedness and competence will also be highlighted. This study added to the body of knowledge regarding contextual factors and the impact those factors have on pharmacy students' need satisfaction by illustrating that not all factors (family, lecturers, peers and workload) can be considered equal. Lecturers ought to recognise the important role family and peers play in the emotional and mental wellbeing of students and utilise those factors in their teaching. The mechanism of basic psychological need satisfaction as described in Self-determination theory provide insight into pharmacy students' optimal functioning. Hence the influence of contextual factors, (lecturers, peers, family and workload) on the need satisfaction was investigated by means of a survey. The structural model explained 46%, 25% and 30% of the variances in autonomy, competence and relatedness satisfaction and 26% of the variance in psychological need frustration. Family and Peer support contributed the most to the variance explained of the variables. Lecturers should acknowledge this important role of family and peers and utilise this premise when they design learning encounters. Copyright © 2017 Elsevier Inc. All rights reserved.
Klassen, Anne F; Raina, Parminder; McIntosh, Cameron; Sung, Lillian; Klaassen, Robert J; O'Donnell, Maureen; Yanofsky, Rochelle; Dix, David
2011-09-01
Research with parents of children with cancer has identified factors related to their adjustment and coping, but it is not fully understood why some parents do well and others do not. Guided by a stress process model, we examined the interrelationships among a comprehensive set of factors to identify the most important determinants of health-related quality of life (HRQoL) in parents of children in active treatment for cancer. A cross-sectional survey of 411 parents (80% response rate) of children receiving cancer treatment in Canada was conducted between November 2004 and February 2007. The following constructs were measured: background and context factors, child characteristics, family-centered service delivery, caregiver strain, intrapsychic factors, coping/supportive factors and parental HRQoL. The model was evaluated using structural equation modeling. Analysis was stratified by time since diagnosis (i.e., <12 months and ≥12 months). For those within 12 months of their child's diagnosis, family-centred service provision, caregiver strain, and self-perception accounted for 58% of the variation in psychosocial health, whereas caregiver strain and social support explained 50% of the variation in physical health. For parents in the >12 month group, caregiving strain was the only factor with a direct relationship with parental psychosocial and physical health, accounting for 66% and 55% of the variance in these constructs, respectively. Our findings reinforce the need for health professionals to be particularly attuned to family caregivers in the early stages of treatment and identify potential areas for interventions to promote parental health. Copyright © 2010 UICC.
Do executive functions explain the covariance between internalizing and externalizing behaviors?
Hatoum, Alexander S; Rhee, Soo Hyun; Corley, Robin P; Hewitt, John K; Friedman, Naomi P
2017-11-16
This study examined whether executive functions (EFs) might be common features of internalizing and externalizing behavior problems across development. We examined relations between three EF latent variables (a common EF factor and factors specific to updating working memory and shifting sets), constructed from nine laboratory tasks administered at age 17, to latent growth intercept (capturing stability) and slope (capturing change) factors of teacher- and parent-reported internalizing and externalizing behaviors in 885 individual twins aged 7 to 16 years. We then estimated the proportion of intercept-intercept and slope-slope correlations predicted by EF as well as the association between EFs and a common psychopathology factor (P factor) estimated from all 9 years of internalizing and externalizing measures. Common EF was negatively associated with the intercepts of teacher-rated internalizing and externalizing behavior in males, and explained 32% of their covariance; in the P factor model, common EF was associated with the P factor in males. Shifting-specific was positively associated with the externalizing slope across sex. EFs did not explain covariation between parent-rated behaviors. These results suggest that EFs are associated with stable problem behavior variation, explain small proportions of covariance, and are a risk factor that that may depend on gender.
Shimizu, Ken; Nakaya, Naoki; Saito-Nakaya, Kumi; Akechi, Tatsuo; Ogawa, Asao; Fujisawa, Daisuke; Sone, Toshimasa; Yoshiuchi, Kazuhiro; Goto, Koichi; Iwasaki, Motoki; Tsugane, Shoichiro; Uchitomi, Yosuke
2015-05-01
Although various factors thought to be correlated with anxiety in cancer patients, relative importance of each factors were unknown. We tested our hypothesis that personality traits and coping styles explain anxiety in lung cancer patients to a greater extent than other factors. A total of 1334 consecutively recruited lung cancer patients were selected, and data on cancer-related variables, demographic characteristics, health behaviors, physical symptoms and psychological factors consisting of personality traits and coping styles were obtained. The participants were divided into groups with or without a significant anxiety using the Hospital Anxiety and Depression Scale-Anxiety, and a binary logistic regression analysis was used to identify factors correlated with significant anxiety using a multivariate model. Among the recruited patients, 440 (33.0%) had significant anxiety. The binary logistic regression analysis revealed a coefficient of determination (overall R(2)) of 39.0%, and the explanation for psychological factors was much higher (30.7%) than those for cancer-related variables (1.1%), demographic characteristics (2.1%), health behaviors (0.8%) and physical symptoms (4.3%). Four specific factors remained significant in a multivariate model. A neurotic personality trait, a coping style of helplessness/hopelessness, and a female sex were positively correlated with significant anxiety, while a coping style of fatalism was negatively correlated. Our hypothesis was supported, and anxiety was strongly linked with personality trait and coping style. As a clinical implication, the use of screening instruments to identify these factors and intervention for psychological crisis may be needed. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Carter, Megan Ann; Dubois, Lise; Tremblay, Mark S; Taljaard, Monica
2013-04-01
The objective of this paper was to determine the influence of place factors on weight gain in a contemporary cohort of children while also adjusting for early life and individual/family social factors. Participants from the Québec Longitudinal Study of Child Development comprised the sample for analysis (n = 1,580). A mixed-effects regression analysis was conducted to determine the longitudinal relationship between these place factors and standardized BMI, from age 4 to 10 years. The average relationship with time was found to be quadratic (rate of weight gain increased over time). Neighborhood material deprivation was found to be positively related to weight gain. Social deprivation, social disorder, and living in a medium density area were inversely related, while no association was found for social cohesion. Early life factors and genetic proxies appeared to be important in explaining weight gain in this sample. This study suggests that residential environments may play a role in childhood weight change; however, pathways are likely to be complex and interacting and perhaps not as important as early life factors and genetic proxies. Further work is required to clarify these relationships.
Climate and topography explain range sizes of terrestrial vertebrates
NASA Astrophysics Data System (ADS)
Li, Yiming; Li, Xianping; Sandel, Brody; Blank, David; Liu, Zetian; Liu, Xuan; Yan, Shaofei
2016-05-01
Identifying the factors that influence range sizes of species provides important insight into the distribution of biodiversity, and is crucial for predicting shifts in species ranges in response to climate change. Current climate (for example, climate variability and climate extremes), long-term climate change, evolutionary age, topographic heterogeneity, land area and species traits such as physiological thermal limits, dispersal ability, annual fecundity and body size have been shown to influence range size. Yet, few studies have examined the generality of each of these factors among different taxa, or have simultaneously evaluated the strength of relationships between range size and these factors at a global scale. We quantify contributions of these factors to range sizes of terrestrial vertebrates (mammals, birds and reptiles) at a global scale. We found that large-ranged species experience greater monthly extremes of maximum or minimum temperature within their ranges, or occur in areas with higher long-term climate velocity and lower topographic heterogeneity or lower precipitation seasonality. Flight ability, body mass and continent width are important only for particular taxa. Our results highlight the importance of climate and topographic context in driving range size variation. The results suggest that small-range species may be vulnerable to climate change and should be the focus of conservation efforts.
Martin-Fernandez, Laura; Ziyatdinov, Andrey; Carrasco, Marina; Millon, Juan Antonio; Martinez-Perez, Angel; Vilalta, Noelia; Brunel, Helena; Font, Montserrat; Hamsten, Anders; Souto, Juan Carlos; Soria, José Manuel
2016-01-01
Background Venous thromboembolism (VTE) is a common disease where known genetic risk factors explain only a small portion of the genetic variance. Then, the analysis of intermediate phenotypes, such as thrombin generation assay, can be used to identify novel genetic risk factors that contribute to VTE. Objectives To investigate the genetic basis of distinct quantitative phenotypes of thrombin generation and its relationship to the risk of VTE. Patients/Methods Lag time, thrombin peak and endogenous thrombin potential (ETP) were measured in the families of the Genetic Analysis of Idiopathic Thrombophilia 2 (GAIT-2) Project. This sample consisted of 935 individuals in 35 extended families selected through a proband with idiopathic thrombophilia. We performed also genome wide association studies (GWAS) with thrombin generation phenotypes. Results The results showed that 67% of the variation in the risk of VTE is attributable to genetic factors. The heritabilities of lag time, thrombin peak and ETP were 49%, 54% and 52%, respectively. More importantly, we demonstrated also the existence of positive genetic correlations between thrombin peak or ETP and the risk of VTE. Moreover, the major genetic determinant of thrombin generation was the F2 gene. However, other suggestive signals were observed. Conclusions The thrombin generation phenotypes are strongly genetically determined. The thrombin peak and ETP are significantly genetically correlated with the risk of VTE. In addition, F2 was identified as a major determinant of thrombin generation. We reported suggestive signals that might increase our knowledge to explain the variability of this important phenotype. Validation and functional studies are required to confirm GWAS results. PMID:26784699
NASA Astrophysics Data System (ADS)
Shi, Z. H.
2014-12-01
There are strong ties between land use and sediment yield in watersheds. Many studies have used multivariate regression techniques to explore the response of sediment yield to land-use compositions and spatial configurations in watersheds. However, one issue with the use of conventional statistical methods to address relationships between land-use compositions and spatial configurations and sediment yield is multicollinearity. This paper examines the combined effects of land-use compositions and land-use spatial configurations of the watershed on the specific sediment yield of the Upper Du River watershed (8,973 km2) in China using the Soil and Water Assessment Tool (SWAT) and partial least-squares regression (PLSR). The land-use compositions and spatial configurations of the watershed were calculated at the sub-watershed scale. The sediment yields from sub-watershed were evaluated using SWAT model. The first-order factors were identified by calculating the variable importance for the projection (VIP). The results revealed that the land-use compositions exerted the largest effects on the specific sediment yield and explained 61.2% of the variation in the specific sediment yield. Land-use spatial configurations were also found to have a large effect on the specific sediment yield and explained 21.7% of the observed variation in the specific sediment yield. The following are the dominant first-order factors of the specific sediment yield at the sub-watershed scale: the areal percentages of agriculture and forest, patch density, value of the Shannon's diversity index, contagion. The VIP values suggested that the Shannon's diversity index and contagion are important factors for sediment delivery.
Ethnic density of regions and psychiatric disorders among ethnic minority individuals.
Emerson, Scott Daniel; Minh, Anita; Guhn, Martin
2018-03-01
Ethnic minorities form an increasingly large proportion of Canada's population. Living in areas of greater ethnic density may help protect mental health among ethnic minorities through psychosocial pathways such as accessibility to culturally appropriate provision of mental health care, less discrimination and a greater sense of belonging. Mood and anxiety disorders are common psychiatric disorders. This study examined whether ethnic density of regions was related to mood and anxiety disorders among ethnic minorities in Canada. Responses by ethnic minority individuals to the 2011-2014 administrations of the Canadian Community Health Survey ( n = 33,201) were linked to health region ethnic density data. Multilevel logistic regression was employed to model the odds of having mood and/or anxiety disorders associated with increasing region-level ethnic density and to examine whether sense of community belonging helped explain variance in such associations. Analyses were adjusted for individual-level demographic factors as well as region-level socio-economic factors. Higher ethnic density related to lower odds of mood and/or anxiety disorders for Canadian-born (but not foreign-born) ethnic minorities. Sense of community belonging did not help explain such associations, but independently related to lower odds of mood and/or anxiety disorders. These findings remained after adjusting for regional population density and after excluding (rural/remote) regions of very low ethnic density. Ethnic density of regions in Canada may be an important protective factor against mental illness among Canadian-born ethnic minorities. It is important to better understand how, and for which specific ethno-cultural groups, ethnic density may influence mental health.
Perceived game realism: a test of three alternative models.
Ribbens, Wannes
2013-01-01
Perceived realism is considered a key concept in explaining the mental processing of media messages and the societal impact of media. Despite its importance, little is known about its conceptualization and dimensional structure, especially with regard to digital games. The aim of this study was to test a six-factor model of perceived game realism comprised of simulational realism, freedom of choice, perceptual pervasiveness, social realism, authenticity, and character involvement and to assess it against an alternative single- and five-factor model. Data were collected from 380 male digital game users who judged the realism of the first-person shooter Half-Life 2 based upon their previous experience with the game. Confirmatory factor analysis was applied to investigate which model fits the data best. The results support the six-factor model over the single- and five-factor solutions. The study contributes to our knowledge of perceived game realism by further developing its conceptualization and measurement.
[The participation of seniors in volunteer activities: a systematic review].
Godbout, Elisabeth; Filiatrault, Johanne; Plante, Michelle
2012-02-01
Volunteer work can be a very significant form of social participation for seniors. It can also provide seniors with important physical and psychological health benefits. This explains why occupational therapists and other health care professionals, as well as community workers who are concerned with healthy aging, appeal to seniors to volunteer in health promotion and community support However, the recruitment and ongoing involvement of seniors as volunteers is often challenging. A systematic review of the literature was undertaken to enlighten practitioners working in this domain. The objective was to identify factors that influence seniors' participation in volunteer work. Six bibliographic databases were searched using key words. A total of 27 relevant papers were retrieved and allowed an identification of a series of factors that could influence seniors' participation in volunteer work, namely personal factors, environmental factors, and occupational factors. This analysis leads to practical guidelines for facilitating the recruitment and maintenance of seniors' engagement in volunteer work.
Miftahussurur, Muhammad; Yamaoka, Yoshio
2015-01-01
Helicobacter pylori infection plays an important role in the pathogenesis of peptic ulcer disease (PUD). Several factors have been proposed as possible H. pylori virulence determinants; for example, bacterial adhesins and gastric inflammation factors are associated with an increased risk of PUD. However, differences in bacterial virulence factors alone cannot explain the opposite ends of the PUD disease spectrum, that is duodenal and gastric ulcers; presumably, both bacterial and host factors contribute to the differential response. Carriers of the high-producer alleles of the pro-inflammatory cytokines IL-1B, IL-6, IL-8, IL-10, and TNF-α who also carry low-producer allele of anti-inflammatory cytokines have severe gastric mucosal inflammation, whereas carriers of the alternative alleles have mild inflammation. Recent reports have suggested that the PSCA and CYP2C19 ultra-rapid metabolizer genotypes are also associated with PUD.
Gornish, Elise S; Miller, Thomas E
2015-01-01
Increasing rates of change in climate have been observed across the planet and have contributed to the ongoing range shifts observed for many species. Although ecologists are now using a variety of approaches to study how much and through what mechanisms increasing temperature and nutrient pollution may influence the invasions inherent in range shifts, accurate predictions are still lacking. In this study, we conducted a factorial experiment, simultaneously manipulating warming, nitrogen addition and introduction of Pityopsis aspera, to determine how range-shifting species affect a plant community. We quantified the resident community using ordination scores, then used structural equation modeling to examine hypotheses related to how plants respond to a network of experimental treatments and environmental variables. Variation in soil pH explained plant community response to nitrogen addition in the absence of invasion. However, in the presence of invasion, the direct effect of nitrogen on the community was negligible and soil moisture was important for explaining nitrogen effects. We did not find effects of warming on the native plant community in the absence of invasion. In the presence of invasion, however, warming had negative effects on functional richness directly and invasion and herbivory explained the overall positive effect of warming on the plant community. This work highlights the variation in the biotic and abiotic factors responsible for explaining independent and collective climate change effects over a short time scale. Future work should consider the complex and non-additive relationships among factors of climate change and invasion in order to capture more ecologically relevant features of our changing environment.
NASA Astrophysics Data System (ADS)
He, Jiaying; Wang, Kai; Xiong, Jinbo; Guo, Annan; Zhang, Demin; Fei, Yuejun; Ye, Xiansen
2017-04-01
Anthropogenic nutrient discharge poses widespread threats to coastal ecosystems and has increased environmental gradients from coast to sea. Bacterioplankton play crucial roles in coastal biogeochemical cycling, and a variety of factors affect bacterial community diversity and structure. We used 16S rRNA gene pyrosequencing to investigate the spatial variation in bacterial community composition (BCC) across five sites on a coast-offshore gradient in the East China Sea. Overall, bacterial alpha-diversity did not differ across sites, except that richness and phylogenetic diversity were lower in the offshore sites, and the highest alpha-diversity was found in the most landward site, with Chl-a being the main factor. BCCs generally clustered into coastal and offshore groups. Chl-a explained 12.3% of the variation in BCCs, more than that explained by either the physicochemical (5.7%) or spatial (8.5%) variables. Nutrients (particularly nitrate and phosphate), along with phytoplankton abundance, were more important than other physicochemical factors, co-explaining 20.0% of the variation in BCCs. Additionally, a series of discriminant families (primarily affiliated with Gammaproteobacteria and Alphaproteobacteria), whose relative abundances correlated with Chl-a, DIN, and phosphate concentrations, were identified, implying their potential to indicate phytoplankton blooms and nutrient enrichment in this marine ecosystem. This study provides insight into bacterioplankton response patterns along a coast-offshore gradient, with phytoplankton abundance increasing in the offshore sites. Time-series sampling across multiple transects should be performed to determine the seasonal and spatial patterns in bacterial diversity and community structure along this gradient.
NASA Astrophysics Data System (ADS)
He, Jiaying; Wang, Kai; Xiong, Jinbo; Guo, Annan; Zhang, Demin; Fei, Yuejun; Ye, Xiansen
2018-03-01
Anthropogenic nutrient discharge poses widespread threats to coastal ecosystems and has increased environmental gradients from coast to sea. Bacterioplankton play crucial roles in coastal biogeochemical cycling, and a variety of factors affect bacterial community diversity and structure. We used 16S rRNA gene pyrosequencing to investigate the spatial variation in bacterial community composition (BCC) across five sites on a coast-offshore gradient in the East China Sea. Overall, bacterial alpha-diversity did not differ across sites, except that richness and phylogenetic diversity were lower in the offshore sites, and the highest alpha-diversity was found in the most landward site, with Chl-a being the main factor. BCCs generally clustered into coastal and offshore groups. Chl-a explained 12.3% of the variation in BCCs, more than that explained by either the physicochemical (5.7%) or spatial (8.5%) variables. Nutrients (particularly nitrate and phosphate), along with phytoplankton abundance, were more important than other physicochemical factors, co-explaining 20.0% of the variation in BCCs. Additionally, a series of discriminant families (primarily affiliated with Gammaproteobacteria and Alphaproteobacteria), whose relative abundances correlated with Chl-a, DIN, and phosphate concentrations, were identified, implying their potential to indicate phytoplankton blooms and nutrient enrichment in this marine ecosystem. This study provides insight into bacterioplankton response patterns along a coast-offshore gradient, with phytoplankton abundance increasing in the offshore sites. Time-series sampling across multiple transects should be performed to determine the seasonal and spatial patterns in bacterial diversity and community structure along this gradient.
Luiz, Amom Mendes; Sawaya, Ricardo J.
2018-01-01
Ecological communities are complex entities that can be maintained and structured by niche-based processes such as environmental conditions, and spatial processes such as dispersal. Thus, diversity patterns may be shaped simultaneously at different spatial scales by very distinct processes. Herein we assess whether and how functional, taxonomic, and phylogenetic beta diversities of frog tadpoles are explained by environmental and/or spatial predictors. We implemented a distance–based redundancy analysis to explore variation in components of beta diversity explained by pure environmental and pure spatial predictors, as well as their interactions, at both fine and broad spatial scales. Our results indicated important but complex roles of spatial and environmental predictors in structuring phylogenetic, taxonomic and functional beta diversities. The pure fine-scales spatial fraction was more important in structuring all beta diversity components, especially to functional and taxonomical spatial turnover. Environmental variables such as canopy cover and vegetation structure were important predictors of all components, but especially to functional and taxonomic beta diversity. We emphasize that distinct factors related to environment and space are affecting distinct components of beta diversity in different ways. Although weaker, phylogenetic beta diversity, which is structured more on biogeographical scales, and thus can be represented by spatially structured processes, was more related to broad spatial processes than other components. However, selected fine-scale spatial predictors denoted negative autocorrelation, which may be revealing the existence of differences in unmeasured habitat variables among samples. Although overall important, local environmental-based processes explained better functional and taxonomic beta diversity, as these diversity components carry an important ecological value. We highlight the importance of assessing different components of diversity patterns at different scales by spatially explicit models in order to improve our understanding of community structure and help to unravel the complex nature of biodiversity. PMID:29672575
Wu, Sheng-Hui; Ozaki, Koken; Reed, Terry; Krasnow, Ruth E; Dai, Jun
2017-07-01
This study examined genetic and environmental influences on the lipid concentrations of 1028 male twins using the novel univariate non-normal structural equation modeling (nnSEM) ADCE and ACE models. In the best fitting nnSEM ADCE model that was also better than the nnSEM ACE model, additive genetic factors (A) explained 4%, dominant genetic factors (D) explained 17%, and common (C) and unique (E) environmental factors explained 47% and 33% of the total variance of high-density lipoprotein cholesterol (HDL-C). The percentage of variation explained for other lipids was 0% (A), 30% (D), 34% (C) and 37% (E) for low-density lipoprotein cholesterol (LDL-C); 30, 0, 31 and 39% for total cholesterol; and 0, 31, 12 and 57% for triglycerides. It was concluded that additive and dominant genetic factors simultaneously affected HDL-C concentrations but not other lipids. Common and unique environmental factors influenced concentrations of all lipids.
Gebreab, Samson Y; Davis, Sharon K; Symanzik, Jürgen; Mensah, George A; Gibbons, Gary H; Diez-Roux, Ana V
2015-01-01
Background Improving cardiovascular health (CVH) of all Americans by 2020 is a strategic goal of the American Heart Association. Understanding the sources of variation and identifying contextual factors associated with poor CVH may suggest important avenues for prevention. Methods and Results Cross-sectional data from the Behavioral Risk Factor Surveillance System for the year 2011 were linked to state-level coronary heart disease and stroke mortality data from the National Vital Statistics System and to state-level measures of median household income, income inequality, taxes on soda drinks and cigarettes, and food and physical activity environments from various administrative sources. Poor CVH was defined according to the American Heart Association definition using 7 self-reported CVH metrics (current smoking, physical inactivity, obesity, poor diet, hypertension, diabetes, and high cholesterol). Linked micromap plots and multilevel logistic models were used to examine state variation in poor CVH and to investigate the contributions of individual- and state-level factors to this variation. We found significant state-level variation in the prevalence of poor CVH (median odds ratio 1.32, P<0.001). Higher rates of poor CVH and cardiovascular disease mortality were clustered in the southern states. Minority and low socioeconomic groups were strongly associated with poor CVH and explained 51% of the state-level variation in poor CVH; state-level factors explained an additional 28%. State-level median household income (odds ratio 0.89; 95% CI 0.84–0.94), taxes on soda drinks (odds ratio 0.94; 95% CI 0.89–0.99), farmers markets (odds ratio 0.91; 95% CI 0.85–0.98), and convenience stores (odds ratio 1.09; 95% CI 1.01–1.17) were predictive of poor CVH even after accounting for individual-level factors. Conclusions There is significant state-level variation in poor CVH that is partly explained by individual- and state-level factors. Additional longitudinal research is warranted to examine the influence of state-level policies and food and physical activity environments on poor CVH. PMID:26019131
Arriaga, Maria E; Vajdic, Claire M; Canfell, Karen; MacInnis, Robert; Hull, Peter; Magliano, Dianna J; Banks, Emily; Giles, Graham G; Cumming, Robert G; Byles, Julie E; Taylor, Anne W; Shaw, Jonathan E; Price, Kay; Hirani, Vasant; Mitchell, Paul; Adelstein, Barbara-Ann; Laaksonen, Maarit A
2017-06-14
To estimate the Australian cancer burden attributable to lifestyle-related risk factors and their combinations using a novel population attributable fraction (PAF) method that accounts for competing risk of death, risk factor interdependence and statistical uncertainty. 365 173 adults from seven Australian cohort studies. We linked pooled harmonised individual participant cohort data with population-based cancer and death registries to estimate exposure-cancer and exposure-death associations. Current Australian exposure prevalence was estimated from representative external sources. To illustrate the utility of the new PAF method, we calculated fractions of cancers causally related to body fatness or both tobacco and alcohol consumption avoidable in the next 10 years by risk factor modifications, comparing them with fractions produced by traditional PAF methods. Over 10 years of follow-up, we observed 27 483 incident cancers and 22 078 deaths. Of cancers related to body fatness (n=9258), 13% (95% CI 11% to 16%) could be avoided if those currently overweight or obese had body mass index of 18.5-24.9 kg/m 2 . Of cancers causally related to both tobacco and alcohol (n=4283), current or former smoking explains 13% (11% to 16%) and consuming more than two alcoholic drinks per day explains 6% (5% to 8%). The two factors combined explain 16% (13% to 19%): 26% (21% to 30%) in men and 8% (4% to 11%) in women. Corresponding estimates using the traditional PAF method were 20%, 31% and 10%. Our PAF estimates translate to 74 000 avoidable body fatness-related cancers and 40 000 avoidable tobacco- and alcohol-related cancers in Australia over the next 10 years (2017-2026). Traditional PAF methods not accounting for competing risk of death and interdependence of risk factors may overestimate PAFs and avoidable cancers. We will rank the most important causal factors and their combinations for a spectrum of cancers and inform cancer control activities. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
DiLorio, Colleen; Dudley, William N; Soet, Johanna E; McCarty, Frances
2004-12-01
To examine sexual possibility situations (SPS) and protective practices associated with involvement in intimate sexual behaviors and the initiation of sexual intercourse among young adolescents and to determine if protective factors moderate the relationship between SPS and sexual behaviors. Data for these analyses were obtained from the baseline assessment for adolescents conducted as part of an HIV prevention study called "Keepin' it R.E.A.L.!" The study was conducted with a community-based organization (CBO) in an urban area serving a predominantly African-American population. In addition to items assessing SPS, intimate sexual behaviors, and initiation of sexual intercourse, adolescents provided information on the following protective factors: educational goals, self-concept, future time perspective, orientation to health, self-efficacy, outcome expectations, parenting, communication, values, and prosocial activities. Background personal information, including age and gender, was also collected. The analyses were conducted on data from 491 predominantly African-American adolescents, 61% of whom were boys. Variables were combined to form SPS and protective indices that were used in the first set of regression analyses. In a second set of analyses, the indices were unbundled and individual variables were entered into regression analyses. Both SPS and protective indices explained significant portions of variance in intimate sexual behaviors, and the SPS index explained a significant portion of variance in the initiation of sexual intercourse. The regression analysis using the unbundled SPS and protective factors revealed the following statistically significant predictors for intimate sexual behaviors: age, gender, time alone with groups of peers, time alone with a member of the opposite sex, behavior self-concept, popularity self-concept, self-efficacy for abstinence, outcome expectations for abstinence, parental control, personal values, and parental values. A similar regression analysis revealed that age, time alone with a member of the opposite sex, and personal values were significant predictors of initiation of sexual intercourse. These results provide evidence for the important role of protective factors in explaining early involvement in sexual behaviors and show that protective factors extend beyond personal characteristics to include both familial and peer factors.
Jenkins, Marion W; Cairncross, Sandy
2010-03-01
Latrine diffusion patterns across 502 villages in Benin, West Africa, were analysed to explore factors driving initial and increasing levels of household adoption in low-coverage rural areas of sub-Saharan Africa. Variables explaining adoption related to population density, size, infrastructure/services, non-agricultural occupations, road and urban proximity, and the nearby latrine adoption rate, capturing differences in the physical and social environment, lifestyles and latrine exposure involved in stimulating status/prestige and well-being reasons for latrine adoption. Contagion was most important in explaining adoption initiation. Cluster analysis revealed four distinct village typologies of demand for latrines which provide a framework for tailoring promotional interventions to better match the different sanitation demand characteristics of communities in scaling-up sanitation development and promotion programmes.
Quaternary coral reef refugia preserved fish diversity.
Pellissier, Loïc; Leprieur, Fabien; Parravicini, Valeriano; Cowman, Peter F; Kulbicki, Michel; Litsios, Glenn; Olsen, Steffen M; Wisz, Mary S; Bellwood, David R; Mouillot, David
2014-05-30
The most prominent pattern in global marine biogeography is the biodiversity peak in the Indo-Australian Archipelago. Yet the processes that underpin this pattern are still actively debated. By reconstructing global marine paleoenvironments over the past 3 million years on the basis of sediment cores, we assessed the extent to which Quaternary climate fluctuations can explain global variation in current reef fish richness. Comparing global historical coral reef habitat availability with the present-day distribution of 6316 reef fish species, we find that distance from stable coral reef habitats during historical periods of habitat loss explains 62% of the variation in fish richness, outweighing present-day environmental factors. Our results highlight the importance of habitat persistence during periods of climate change for preserving marine biodiversity. Copyright © 2014, American Association for the Advancement of Science.
Relative importance of local- and large-scale drivers of alpine soil microarthropod communities.
Mitchell, Ruth J; Urpeth, Hannah M; Britton, Andrea J; Black, Helaina; Taylor, Astrid R
2016-11-01
Nitrogen (N) deposition and climate are acknowledged drivers of change in biodiversity and ecosystem function at large scales. However, at a local scale, their impact on functions and community structure of organisms is filtered by drivers like habitat quality and food quality/availability. This study assesses the relative impact of large-scale factors, N deposition and climate (rainfall and temperature), versus local-scale factors of habitat quality and food quality/availability on soil fauna communities at 15 alpine moss-sedge heaths along an N deposition gradient in the UK. Habitat quality and food quality/availability were the primary drivers of microarthropod communities. No direct impacts of N deposition on the microarthropod community were observed, but induced changes in habitat quality (decline in moss cover and depth) and food quality (decreased vegetation C:N) associated with increased N deposition strongly suggest an indirect impact of N. Habitat quality and climate explained variation in the composition of the Oribatida, Mesostigmata, and Collembola communities, while only habitat quality significantly impacted the Prostigmata. Food quality and prey availability were important in explaining the composition of the oribatid and mesostigmatid mite communities, respectively. This study shows that, in alpine habitats, soil microarthropod community structure responds most strongly to local-scale variation in habitat quality and food availability rather than large-scale variation in climate and pollution. However, given the strong links between N deposition and the key habitat quality parameters, we conclude that N deposition indirectly drives changes in the soil microarthropod community, suggesting a mechanism by which large-scale drivers indirectly impacts these functionally important groups.
Roberto, M C; Santana, N N; Thomaz, S M
2009-06-01
Knowledge of abiotic limnological factors is important to monitor changes caused by humans, and to explain the structure and dynamics of populations and communities in a variety of inland water ecosystems. In this study, we used a long term data-set (eight years) collected in 10 habitats with different features (river channels, and connected and isolated lakes) to describe the spatial and temporal patterns of some of the principal limnological factors. In general, the degree of connectivity of the lakes, together with the rivers to which the lakes are connected, were important determinants of their limnological characteristics. These differences are expected, because rivers entering the floodplain come from different geological regions and are subject to different human impacts. At large spatial scales, these differences contribute to the increased habitat diversity of the floodplain and thus to its high biodiversity. With regard to temporal variation, Secchi-disk transparency increased, and total phosphorus decreased in the Paraná River main channel during the last 20 years. Although these changes are directly attributed to the several reservoir cascades located upstream, the closing of the Porto Primavera dam in 1998 enhanced this effect. The increase in water transparency explains biotic changes within the floodplain. The lower-phosphorus Paraná River water probably dilutes concentrations of this element in the floodplain waterbodies during major floods, with future consequences for their productivity.
The mass media are an important context for adolescents' sexual behavior.
L'Engle, Kelly Ladin; Brown, Jane D; Kenneavy, Kristin
2006-03-01
This study compared influences from the mass media (television, music, movies, magazines) on adolescents' sexual intentions and behaviors to other socialization contexts, including family, religion, school, and peers. A sample of 1011 Black and White adolescents from 14 middle schools in the Southeastern United States completed linked mail surveys about their media use and in-home Audio-CASI interviews about their sexual intentions and behaviors. Analysis of the sexual content in 264 media vehicles used by respondents was also conducted. Exposure to sexual content across media, and perceived support from the media for teen sexual behavior, were the main media influence measures. Media explained 13% of the variance in intentions to initiate sexual intercourse in the near future, and 8-10% of the variance in light and heavy sexual behaviors, which was comparable to other contexts. Media influences also demonstrated significant associations with intentions and behaviors after all other factors were considered. All contextual factors, including media, explained 54% of the variance in sexual intentions and 21-33% of the variance in sexual behaviors. Adolescents who are exposed to more sexual content in the media, and who perceive greater support from the media for teen sexual behavior, report greater intentions to engage in sexual intercourse and more sexual activity. Mass media are an important context for adolescents' sexual socialization, and media influences should be considered in research and interventions with early adolescents to reduce sexual activity.
Tsiknia, Myrto; Paranychianakis, Nikolaos V; Varouchakis, Emmanouil A; Moraetis, Daniel; Nikolaidis, Nikolaos P
2014-10-01
Data on soil microbial community distribution at large scales are limited despite the important information that could be drawn with regard to their function and the influence of environmental factors on nutrient cycling and ecosystem services. This study investigates the distribution of Archaea, Bacteria and Fungi as well as the dominant bacterial phyla (Acidobacteria, Actinobacteria, Bacteroidetes, Firmicutes), and classes of Proteobacteria (Alpha- and Betaproteobacteria) across the Koiliaris watershed by qPCR and associate them with environmental variables. Predictive maps of microorganisms distribution at watershed scale were generated by co-kriging, using the most significant predictors. Our findings showed that 31-79% of the spatial variation in microbial taxa abundance could be explained by the parameters measured, with total organic carbon and pH being identified as the most important. Moreover, strong correlations were set between microbial groups and their inclusion on variance explanation improved the prediction power of the models. The spatial autocorrelation of microbial groups ranged from 309 to 2.226 m, and geographic distance, by itself, could explain a high proportion of their variation. Our findings shed light on the factors shaping microbial communities at a high taxonomic level and provide evidence for ecological coherence and syntrophic interactions at the watershed scale. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.
Relationship Between Landcover Pattern and Surface Net Radiation in AN Coastal City
NASA Astrophysics Data System (ADS)
Zhao, X.; Liu, L.; Liu, X.; Zhao, Y.
2016-06-01
Taking Xiamen city as the study area this research first retrieved surface net radiation using meteorological data and Landsat 5 TM images of the four seasons in the year 2009. Meanwhile the 65 different landscape metrics of each analysis unit were acquired using landscape analysis method. Then the most effective landscape metrics affecting surface net radiation were determined by correlation analysis, partial correlation analysis, stepwise regression method, etc. At both class and landscape levels, this paper comprehensively analyzed the temporal and spatial variations of the surface net radiation as well as the effects of land cover pattern on it in Xiamen from a multi-seasonal perspective. The results showed that the spatial composition of land cover pattern shows significant influence on surface net radiation while the spatial allocation of land cover pattern does not. The proportions of bare land and forest land are effective and important factors which affect the changes of surface net radiation all the year round. Moreover, the proportion of forest land is more capable for explaining surface net radiation than the proportion of bare land. So the proportion of forest land is the most important and continuously effective factor which affects and explains the cross-seasonal differences of surface net radiation. This study is helpful in exploring the formation and evolution mechanism of urban heat island. It also gave theoretical hints and realistic guidance for urban planning and sustainable development.
Determinants of virtual water flows in the Mediterranean.
Fracasso, Andrea; Sartori, Martina; Schiavo, Stefano
2016-02-01
The aim of the paper is to investigate the main determinants of the bilateral virtual water (water used in the production of a commodity or service) flows associated with international trade in agricultural goods across the Mediterranean basin. We consider the bilateral gross flows of virtual water in the area and study what export-specific and import-specific factors are significantly associated with virtual water flows. We follow a sequential approach. Through a gravity model of trade, we obtain a "refined" version of the variable we aim to explain, one that is free of the amount of flows due to pair-specific factors affecting bilateral trade flows and that fully reflects the impact of country-specific determinants of virtual water trade. A number of country-specific potential explanatory variables, ranging from water endowments to trade barriers, from per capita GDP to irrigation prices, is presented and tested. To identify the variables that help to explain the bilateral flows of virtual water, we adopt a model selection procedure based on model averaging. Our findings confirm one of the main controversial results in the literature: larger water endowments do not necessarily lead to a larger 'export' of virtual water, as one could expect. We also find some evidence that higher water irrigation prices reduce (increase) virtual water 'exports' ('imports'). Copyright © 2015 Elsevier B.V. All rights reserved.
Conceptual Foundations of Systems Biology Explaining Complex Cardiac Diseases.
Louridas, George E; Lourida, Katerina G
2017-02-21
Systems biology is an important concept that connects molecular biology and genomics with computing science, mathematics and engineering. An endeavor is made in this paper to associate basic conceptual ideas of systems biology with clinical medicine. Complex cardiac diseases are clinical phenotypes generated by integration of genetic, molecular and environmental factors. Basic concepts of systems biology like network construction, modular thinking, biological constraints (downward biological direction) and emergence (upward biological direction) could be applied to clinical medicine. Especially, in the field of cardiology, these concepts can be used to explain complex clinical cardiac phenotypes like chronic heart failure and coronary artery disease. Cardiac diseases are biological complex entities which like other biological phenomena can be explained by a systems biology approach. The above powerful biological tools of systems biology can explain robustness growth and stability during disease process from modulation to phenotype. The purpose of the present review paper is to implement systems biology strategy and incorporate some conceptual issues raised by this approach into the clinical field of complex cardiac diseases. Cardiac disease process and progression can be addressed by the holistic realistic approach of systems biology in order to define in better terms earlier diagnosis and more effective therapy.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kolhoff, Arend J., E-mail: akolhoff@eia.nl; Driessen, Peter P.J., E-mail: p.driessen@uu.nl; Runhaar, Hens A.C., E-mail: h.a.c.runhaar@uu.nl
2013-01-15
Actors in the field of international development co-operation supporting the development of EIA legislation in developing countries often do not achieve the results envisaged. The performance of EIA in these countries often remains weak. One reason, we assume, is that often those actors support the establishment of overly ambitious EIA legislation that cannot achieve its objectives in the light of constraining contexts. To provide more effective support we need to better understand the enabling and constraining contextual factors that influence the development of EIA legislation and to which support actors should align itself. In this article a new analysis frameworkmore » for classifying, characterizing and explaining the development of EIA legislation is described, measured in terms of ambition levels. Ambitions are defined as intentions the EIA authorities aim to fulfill, expressed in formal EIA legislation. Three country cases, Yemen, Georgia and Ghana are used to illustrate the usefulness of our framework and as a first test to refine the framework. We have formulated the following five hypotheses that complement and refine our analysis framework. One, EIA legislation may develop multilinearly in terms of ambition levels. Two, ambitions in EIA legislation seem to be influenced to a great extent by the power and capacity of, on the one hand, the environmental authorities supporting EIA and, on the other hand, the sector authorities hindering the development of EIA. Three, the political system is the most important context factor influencing the rules of policy-making and the power of the different actors involved. Four, the importance of context factors on the development of ambitions is dependent on the phase of EIA system development. Five, some ambitions seem to be influenced by particular factors; for instance the ambitions for the object of study seem to be influenced by the level of environmental awareness of the sector ministries and parliament. The analysis framework may also assist actors involved in the development of EIA legislation in setting ambitions for EIA legislation that are feasible within the context in which it will be developed and implemented. Application of a country-specific EIA model would seem to be the preferred model to develop EIA legislation because by taking capacities of actors and context factors as a starting point, it offers more potential to well-performing EIA systems. - Highlights: Black-Right-Pointing-Pointer EIA systems develop from less to high ambitious and sometimes vice versa. Black-Right-Pointing-Pointer Ambitions in EIA legislation are determined by the capacity of environment- and sector authority. Black-Right-Pointing-Pointer The political system is the most important context factor explaining the ambitions of an EIA system. Black-Right-Pointing-Pointer An analysis framework developed to measure EIA system ambitions might help to setambitions.« less
Key factors in children's competence to consent to clinical research.
Hein, Irma M; Troost, Pieter W; Lindeboom, Robert; Benninga, Marc A; Zwaan, C Michel; van Goudoever, Johannes B; Lindauer, Ramón J L
2015-10-24
Although law is established on a strong presumption that persons younger than a certain age are not competent to consent, statutory age limits for asking children's consent to clinical research differ widely internationally. From a clinical perspective, competence is assumed to involve many factors including the developmental stage, the influence of parents and peers, and life experience. We examined potential determining factors for children's competence to consent to clinical research and to what extent they explain the variation in competence judgments. From January 1, 2012 through January 1, 2014, pediatric patients aged 6 to 18 years, eligible for clinical research studies were enrolled prospectively at various in- and outpatient pediatric departments. Children's competence to consent was assessed by MacArthur Competence Assessment Tool for Clinical Research. Potential determining child variables included age, gender, intelligence, disease experience, ethnicity and socio-economic status (SES). We used logistic regression analysis and change in explained variance in competence judgments to quantify the contribution of a child variable to the total explained variance. Contextual factors included risk and complexity of the decision to participate, parental competence judgment and the child's or parents decision to participate. Out of 209 eligible patients, 161 were included (mean age, 10.6 years, 47.2 % male). Age, SES, intelligence, ethnicity, complexity, parental competence judgment and trial participation were univariately associated with competence (P < 0.05). Total explained variance in competence judgments was 71.5 %. Only age and intelligence significantly and independently explained the variance in competence judgments, explaining 56.6 % and 12.7 % of the total variance respectively. SES, male gender, disease experience and ethnicity each explained less than 1 % of the variance in competence judgments. Contextual factors together explained an extra 2.8 % (P > 0.05). Age is the factor that explaines most of to the variance in children's competence to consent, followed by intelligence. Experience with disease did not affect competence in this study, nor did other variables. Development and use of a standardized instrument for assessing children's competence to consent in drug trials: Are legally established age limits valid?, NTR3918.
Local-scale drivers of tree survival in a temperate forest.
Wang, Xugao; Comita, Liza S; Hao, Zhanqing; Davies, Stuart J; Ye, Ji; Lin, Fei; Yuan, Zuoqiang
2012-01-01
Tree survival plays a central role in forest ecosystems. Although many factors such as tree size, abiotic and biotic neighborhoods have been proposed as being important in explaining patterns of tree survival, their contributions are still subject to debate. We used generalized linear mixed models to examine the relative importance of tree size, local abiotic conditions and the density and identity of neighbors on tree survival in an old-growth temperate forest in northeastern China at three levels (community, guild and species). Tree size and both abiotic and biotic neighborhood variables influenced tree survival under current forest conditions, but their relative importance varied dramatically within and among the community, guild and species levels. Of the variables tested, tree size was typically the most important predictor of tree survival, followed by biotic and then abiotic variables. The effect of tree size on survival varied from strongly positive for small trees (1-20 cm dbh) and medium trees (20-40 cm dbh), to slightly negative for large trees (>40 cm dbh). Among the biotic factors, we found strong evidence for negative density and frequency dependence in this temperate forest, as indicated by negative effects of both total basal area of neighbors and the frequency of conspecific neighbors. Among the abiotic factors tested, soil nutrients tended to be more important in affecting tree survival than topographic variables. Abiotic factors generally influenced survival for species with relatively high abundance, for individuals in smaller size classes and for shade-tolerant species. Our study demonstrates that the relative importance of variables driving patterns of tree survival differs greatly among size classes, species guilds and abundance classes in temperate forest, which can further understanding of forest dynamics and offer important insights into forest management.
Local-Scale Drivers of Tree Survival in a Temperate Forest
Wang, Xugao; Comita, Liza S.; Hao, Zhanqing; Davies, Stuart J.; Ye, Ji; Lin, Fei; Yuan, Zuoqiang
2012-01-01
Tree survival plays a central role in forest ecosystems. Although many factors such as tree size, abiotic and biotic neighborhoods have been proposed as being important in explaining patterns of tree survival, their contributions are still subject to debate. We used generalized linear mixed models to examine the relative importance of tree size, local abiotic conditions and the density and identity of neighbors on tree survival in an old-growth temperate forest in northeastern China at three levels (community, guild and species). Tree size and both abiotic and biotic neighborhood variables influenced tree survival under current forest conditions, but their relative importance varied dramatically within and among the community, guild and species levels. Of the variables tested, tree size was typically the most important predictor of tree survival, followed by biotic and then abiotic variables. The effect of tree size on survival varied from strongly positive for small trees (1–20 cm dbh) and medium trees (20–40 cm dbh), to slightly negative for large trees (>40 cm dbh). Among the biotic factors, we found strong evidence for negative density and frequency dependence in this temperate forest, as indicated by negative effects of both total basal area of neighbors and the frequency of conspecific neighbors. Among the abiotic factors tested, soil nutrients tended to be more important in affecting tree survival than topographic variables. Abiotic factors generally influenced survival for species with relatively high abundance, for individuals in smaller size classes and for shade-tolerant species. Our study demonstrates that the relative importance of variables driving patterns of tree survival differs greatly among size classes, species guilds and abundance classes in temperate forest, which can further understanding of forest dynamics and offer important insights into forest management. PMID:22347996
Cellular Restriction Factors of Feline Immunodeficiency Virus
Zielonka, Jörg; Münk, Carsten
2011-01-01
Lentiviruses are known for their narrow cell- and species-tropisms, which are determined by cellular proteins whose absence or presence either support viral replication (dependency factors, cofactors) or inhibit viral replication (restriction factors). Similar to Human immunodeficiency virus type 1 (HIV-1), the cat lentivirus Feline immunodeficiency virus (FIV) is sensitive to recently discovered cellular restriction factors from non-host species that are able to stop viruses from replicating. Of particular importance are the cellular proteins APOBEC3, TRIM5α and tetherin/BST-2. In general, lentiviruses counteract or escape their species’ own variant of the restriction factor, but are targeted by the orthologous proteins of distantly related species. Most of the knowledge regarding lentiviral restriction factors has been obtained in the HIV-1 system; however, much less is known about their effects on other lentiviruses. We describe here the molecular mechanisms that explain how FIV maintains its replication in feline cells, but is largely prevented from cross-species infections by cellular restriction factors. PMID:22069525
van Schilfgaarde, R; de Vos, P
1999-01-01
There are several approaches of immunoprotection of pancreatic islets for the purpose of successful allo- or xenotransplantation in the absence of immunosuppressive medication. Extravascular approaches are either macroencapsulation (large numbers of islets together in one device) or microencapsulation. The latter approach is to envelop each individual islet in a semipermeable immunoprotective capsule. Quite promising results have been achieved with polylysine-alginate microencapsulated islet grafts in rodents, but clinical application is still restricted to a very small number of cases. Relevant considerations regard the following aspects. The biocompatibility of the microcapsules is influenced by the chemical composition of the materials applied and by mechanical factors related to the production process. With purified instead of crude alginates, the percentage of capsules with fibrotic overgrowth is reduced to approximately ten percent, and the remaining overgrowth is mainly explained by mechanical factors, i.e. inadequate encapsulation of individual islets. Even with purified alginates, however, the duration of encapsulated graft function is limited to a period of six to twenty weeks. Obviously, other factors than bioincompatibility play a role, which factors have to be identified. The limited duration of graft survival cannot be explained by rejection since, in rats, survival times of encapsulated isografts are similar, if not identical, to those of encapsulated allografts. An important factor is probably insufficient nutrition as a consequence of insufficient blood supply of the encapsulated and thus isolated islet. This also influences the functional performance of encapsulated islet grafts. Although normoglycemia can be readily obtained in streptozotocin diabetic rat recipients, glucose tolerance remains severely impaired, as a consequence of an insufficient increase of insulin levels in response to intravenous or oral glucose challenge. Important factors are the characteristics of the capsules applied in view of optimal diffusion kinetics, and the fact that an encapsulated islet graft can only be implanted in the peritoneal cavity because of its volume. Further studies should focus on finding a practically applicable method to reduce the barrier between encapsulated islets and the bloodstream, in order to improve both the functional performance and the survival of encapsulated islet grafts.
Applied physiology of marathon running.
Sjödin, B; Svedenhag, J
1985-01-01
Performance in marathon running is influenced by a variety of factors, most of which are of a physiological nature. Accordingly, the marathon runner must rely to a large extent on a high aerobic capacity. But great variations in maximal oxygen uptake (VO2 max) have been observed among runners with a similar performance capacity, indicating complementary factors are of importance for performance. The oxygen cost of running or the running economy (expressed, e.g. as VO2 15 at 15 km/h) as well as the fractional utilisation of VO2 max at marathon race pace (%VO2 Ma X VO2 max-1) [where Ma = mean marathon velocity] are additional factors which are known to affect the performance capacity. Together VO2 max, VO2 15 and %VO2 Ma X VO2 max-1 can almost entirely explain the variation in marathon performance. To a similar degree, these variables have also been found to explain the variations in the 'anaerobic threshold'. This factor, which is closely related to the metabolic response to increasing exercise intensities, is the single variable that has the highest predictive power for marathon performance. But a major limiting factor to marathon performance is probably the choice of fuels for the exercising muscles, which factor is related to the %VO2 Ma X VO2 max-1. Present indications are that marathon runners, compared with normal individuals, have a higher turnover rate in fat metabolism at given high exercise intensities expressed both in absolute (m/sec) and relative (%VO2 max) terms. The selection of fat for oxidation by the muscles is important since the stores of the most efficient fuel, the carbohydrates, are limited. The large amount of endurance training done by marathon runners is probably responsible for similar metabolic adaptations, which contribute to a delayed onset of fatigue and raise the VO2 Ma X VO2max-1. There is probably an upper limit in training kilometrage above which there are no improvements in the fractional utilisation of VO2 max at the marathon race pace. The influence of training on VO2 max and, to some extent, on the running economy appears, however, to be limited by genetic factors.
NASA Astrophysics Data System (ADS)
Mor, Amit
Significant amounts of natural gas have been discovered in developing countries throughout the years during the course of oil exploration. The vast majority of these resources have not been utilized. Some developing countries may benefit from a carefully planned utilization of their indigenous resources, which can either be exported or used domestically to substitute imported or exportable fuels or feedstock. Governments, potential private sector investors, and financiers have been searching for strategies to promote natural gas schemes, some of which have been in the pipeline for more than two decades. The purpose of this thesis is to identify the crucial factors determining the success or failure of launching natural gas projects in the developing world. The methodology used to evaluate these questions included: (1) establishing a representative sample of natural gas projects in developing countries that were either implemented or failed to materialize during the 1980-1995 period, (2) utilizing a Probit limited dependent variable econometric model in which the explained variable is project success or failure, and (3) choosing representing indicators to reflect the assumed factors affecting project success. The study identified two conditions for project success: (1) the economic viability of the project and (2) securing financing for the investment. The factors that explain the ability or inability of the sponsors to secure financing were: (1) the volume of investment that represented the large capital costs of gas transportation, distribution, and storage, (2) the level of foreign exchange constraint in the host country, and (3) the level of development of the country. The conditions for private sector participation in natural gas projects in developing countries were identified in the study by a Probit model in which the explained variable was private sector participation. The results showed that a critical condition for private sector participation is the financial profitability of a project. Other factors that explained private sector participation and the ability of the private-sector sponsor to secure financing for a project were: (1) the political risk associated with the project, (2) the foreign exchange constraint associated with the project, and (3) whether the project was domestic or export-oriented.
de la Haye, Kayla; Green, Harold D.; Pollard, Michael S.; Kennedy, David P.; Tucker, Joan S.
2014-01-01
Adolescents often befriend peers who are similar to themselves on a range of demographic, behavioral, and social characteristics, including substance use. Similarities in lifetime history of marijuana use have even been found to predict adolescent friendships, and we examine whether this finding is explained by youth’s selection of friends who are similar on a range of more proximate, observable characteristics that are risk factors for marijuana use. Using two waves of individual and social network data from two high schools that participated in Add Health (N = 1,612; 52.7% male), we apply longitudinal models for social networks to test whether or not several observable risky attributes (psychological, behavioral, and social) predict adolescent friendship choices, and if these preferences explain friend’s similarities on lifetime marijuana use. Findings show that similarities on several risk factors predict friendship choices, however controlling for this, the preference to befriend peers with a similar history of marijuana use largely persists. The results highlight the range of social selection processes that lead to similarities in marijuana use among friends and larger peer groups, and that also give rise to friendship groups whose members share similar risk factors for substance use. Friends with high “collective risk” are likely to be important targets for preventing the onset and social diffusion of substance use in adolescents. PMID:25365913
A complete diet-based algorithm for predicting nonheme iron absorption in adults.
Armah, Seth M; Carriquiry, Alicia; Sullivan, Debra; Cook, James D; Reddy, Manju B
2013-07-01
Many algorithms have been developed in the past few decades to estimate nonheme iron absorption from the diet based on single meal absorption studies. Yet single meal studies exaggerate the effect of diet and other factors on absorption. Here, we propose a new algorithm based on complete diets for estimating nonheme iron absorption. We used data from 4 complete diet studies each with 12-14 participants for a total of 53 individuals (19 men and 34 women) aged 19-38 y. In each study, each participant was observed during three 1-wk periods during which they consumed different diets. The diets were typical, high, or low in meat, tea, calcium, or vitamin C. The total sample size was 159 (53 × 3) observations. We used multiple linear regression to quantify the effect of different factors on iron absorption. Serum ferritin was the most important factor in explaining differences in nonheme iron absorption, whereas the effect of dietary factors was small. When our algorithm was validated with single meal and complete diet data, the respective R(2) values were 0.57 (P < 0.001) and 0.84 (P < 0.0001). The results also suggest that between-person variations explain a large proportion of the differences in nonheme iron absorption. The algorithm based on complete diets we propose is useful for predicting nonheme iron absorption from the diets of different populations.
Home on the Range: Factors Explaining Partial Migration of African Buffalo in a Tropical Environment
Naidoo, Robin; Du Preez, Pierre; Stuart-Hill, Greg; Jago, Mark; Wegmann, Martin
2012-01-01
Partial migration (when only some individuals in a population undertake seasonal migrations) is common in many species and geographical contexts. Despite the development of modern statistical methods for analyzing partial migration, there have been no studies on what influences partial migration in tropical environments. We present research on factors affecting partial migration in African buffalo (Syncerus caffer) in northeastern Namibia. Our dataset is derived from 32 satellite tracking collars, spans 4 years and contains over 35,000 locations. We used remotely sensed data to quantify various factors that buffalo experience in the dry season when making decisions on whether and how far to migrate, including potential man-made and natural barriers, as well as spatial and temporal heterogeneity in environmental conditions. Using an information-theoretic, non-linear regression approach, our analyses showed that buffalo in this area can be divided into 4 migratory classes: migrants, non-migrants, dispersers, and a new class that we call “expanders”. Multimodel inference from least-squares regressions of wet season movements showed that environmental conditions (rainfall, fires, woodland cover, vegetation biomass), distance to the nearest barrier (river, fence, cultivated area) and social factors (age, size of herd at capture) were all important in explaining variation in migratory behaviour. The relative contributions of these variables to partial migration have not previously been assessed for ungulates in the tropics. Understanding the factors driving migratory decisions of wildlife will lead to better-informed conservation and land-use decisions in this area. PMID:22570722
Explaining the increase in coronary heart disease mortality in Syria between 1996 and 2006.
Rastam, Samer; Al Ali, Radwan; Maziak, Wasim; Mzayek, Fawaz; Fouad, Fouad M; O'Flaherty, Martin; Capewell, Simon
2012-09-09
Despite advances made in treating coronary heart disease (CHD), mortality due to CHD in Syria has been increasing for the past two decades. This study aims to assess CHD mortality trends in Syria between 1996 and 2006 and to investigate the main factors associated with them. The IMPACT model was used to analyze CHD mortality trends in Syria based on numbers of CHD patients, utilization of specific treatments, trends in major cardiovascular risk factors in apparently healthy persons and CHD patients. Data sources for the IMPACT model included official statistics, published and unpublished surveys, data from neighboring countries, expert opinions, and randomized trials and meta-analyses. Between 1996 and 2006, CHD mortality rate in Syria increased by 64%, which translates into 6370 excess CHD deaths in 2006 as compared to the number expected had the 1996 baseline rate held constant. Using the IMPACT model, it was estimated that increases in cardiovascular risk factors could explain approximately 5140 (81%) of the CHD deaths, while some 2145 deaths were prevented or postponed by medical and surgical treatments for CHD. Most of the recent increase in CHD mortality in Syria is attributable to increases in major cardiovascular risk factors. Treatments for CHD were able to prevent about a quarter of excess CHD deaths, despite suboptimal implementation. These findings stress the importance of population-based primary prevention strategies targeting major risk factors for CHD, as well as policies aimed at improving access and adherence to modern treatments of CHD.
Wu, Anna H; Pearce, Celeste L; Tseng, Chiu-Chen; Pike, Malcolm C
2015-07-01
Risk factors for invasive epithelial ovarian cancer (IEOC) among Hispanics and African Americans are understudied despite notable differences in incidence relative to non-Hispanic whites. We used multivariate logistic regression to examine parity, oral contraceptive use, tubal ligation, endometriosis, family history of ovarian cancer, and talc use and risk of IEOC among Hispanics (308 cases and 380 controls), African Americans (128 cases and 143 controls), and non-Hispanic whites (1,265 cases and 1,868 controls) using four case-control studies we conducted in Los Angeles County. We expressed each of these factors in the form of increasing risk and calculated population attributable risk percentage (PAR%) estimates for the six risk factors separately and jointly in the three groups. The risk associations with these six well-accepted factors were comparable in the three groups. The significant racial/ethnic differences in the prevalence of these factors and differences in their oophorectomy rates explained 31% of the lower incidence in African Americans compared with non-Hispanic whites, but only 13% of the lower incidence in Hispanics. The PAR%s ranged from 27.5% to 31.0% for no tubal ligation, 15.9% to 22.2% for not using oral contraceptives, and 12.2% to 15.1% for using talc in the three groups. All six risk factors are comparably important in the three groups. Differences in the prevalence of these factors and their oophorectomy rates explained approximately one third of the difference in incidence between African Americans and non-Hispanic whites. Devising strategies to lessen the burden of IEOC will be applicable to all three racial/ethnic groups. ©2015 American Association for Cancer Research.
Lannau, B; Van Geyt, C; Van Maele, G; Beele, H
2015-03-01
During the procurement of musculoskeletal grafts contamination may occur. As this might be detrimental for the acceptor, it is important to know which variables influence this occurrence and to alter procurement protocols accordingly. From 2004 to 2012 we gathered information on 6,428 allografts obtained from 291 donors. Using a multiple regression model we attempted to determine the factors that influence the contamination risk during procurement. We used the following variables: cause of death, type of hospital (i.e. university hospital vs. general hospital), previous blood vessel donation, previous organ donation, donor age, time between death and the start of the procurement, duration of the procurement, number of people attending the procurement and the number of procured grafts. The multiple regression model was only able to explain 5 % of the variability of the used outcome variable. None of the variables examined appear to have an important influence on the contamination risk.
Clinical cognition and diagnostic error: applications of a dual process model of reasoning.
Croskerry, Pat
2009-09-01
Both systemic and individual factors contribute to missed or delayed diagnoses. Among the multiple factors that impact clinical performance of the individual, the caliber of cognition is perhaps the most relevant and deserves our attention and understanding. In the last few decades, cognitive psychologists have gained substantial insights into the processes that underlie cognition, and a new, universal model of reasoning and decision making has emerged, Dual Process Theory. The theory has immediate application to medical decision making and provides an overall schema for understanding the variety of theoretical approaches that have been taken in the past. The model has important practical applications for decision making across the multiple domains of healthcare, and may be used as a template for teaching decision theory, as well as a platform for future research. Importantly, specific operating characteristics of the model explain how diagnostic failure occurs.
Factors Contributing to Mental and Physical Health Care in a Disaster-Prone Environment.
Osofsky, Howard J; Hansel, Tonya Cross; Osofsky, Joy D; Speier, Anthony
2015-01-01
Environment as a contextual factor plays an important role in southeastern Louisiana, as this area represents a major economic hub for the United States port, petroleum, and fishing industries. The location also exposes the population to both natural and technological disasters, including Hurricane Katrina and the Gulf oil spill. This study explored associations among hurricane loss, oil spill disruption, and environmental quality of life on mental and physical health on over 1,000 residents (N = 1,225) using structural equation modeling techniques. Results showed that oil spill distress was associated with increased symptoms of mental and physical health; Hurricane Katrina loss; and decreased environmental quality of life. Findings also indicate that mental health symptoms explain the association among oil spill distress and physical health symptoms-specifically, those that overlap with somatic complaints. These findings provide important support of the need for mental health assessment and service availability for disaster recovery.
NASA Astrophysics Data System (ADS)
Hasell, D. K.;
2018-02-01
The OLYMPUS collaboration has recently made a precise measurement of the positron-proton to electron-proton elastic scattering cross section ratio, R 2γ, over a wide range of the virtual photon polarization, 0.456 < ɛ < 0.978. This provides a direct measure of hard two-photon exchange in elastic lepton-proton scattering widely thought to explain the discrepancy observed between unpolarized and polarized measurements of the proton form factor ratio, {μ }p{G}Ep/{G}Mp. The OLYMPUS results are small, within 1% on unity, over the range of momentum transfers measured and significantly lower than theoretical calculations that can explain part of the observed discrepancy in terms of two-photon exchange at higher momentum transfers. However, the results are in reasonable agreement with predictions based on phenomenological fits to the available form factor data. The motivation for measuring R 2γ will be presented followed by a description of the OLYMPUS experiment. The importance of radiative corrections in the analysis will be shown also. Then we will present the OLYMPUS results and compare with results from two similar experiments and theoretical calculations.
Psychosocial correlates of HIV protection motivation among black adolescents in Venda, South Africa.
Boer, Henk; Mashamba, M Tshilidzi
2005-12-01
We assessed the usefulness of the theory of planned behavior (TPB) and protection motivation theory (PMT) to predict intended condom use among 201 adolescents from Venda, South Africa. Results indicated that both the TPB and the PMT could significantly predict intended condom use, although the level of explained variance was limited. Hierarchical regression analysis indicated that there was considerable overlap between the TPB and the PMT in predicting condom use intention. In the regression analysis that used both the TPB and the PMT variables subjective norms and response efficacy were positively related to intended condom use. The results indicated that both the TPB and the PMT were valuable in explaining intended condom use among African adolescents. The TPB made clear that the social environment is an important contextual factor, whereas the PMT made clear that response efficacy is positively related to condom use intention. The results of this study indicated that social cognition models have some value in the analysis of condom use intention of African adolescents, but the role of other factors like myths about condoms should be further examined.
NASA Astrophysics Data System (ADS)
Deng, Zhipeng; Liang, Fuyou
2016-10-01
An inflatable cuff wrapped around the upper arm is widely used in noninvasive blood pressure measurement. However, the mechanical interaction between cuff and arm tissues, a factor that potentially affects the accuracy of noninvasive blood pressure measurement, remains rarely addressed. In the present study, finite element (FE) models were constructed to quantify intra-arm stresses generated by cuff compression, aiming to provide some theoretical evidence for identifying factors of importance for blood pressure measurement or explaining clinical observations. Obtained results showed that the simulated tissue stresses were highly sensitive to the distribution of cuff pressure on the arm surface and the contact condition between muscle and bone. In contrast, the magnitude of cuff pressure and small variations in elastic properties of arm soft tissues had little influence on the efficiency of pressure transmission in arm tissues. In particular, it was found that a thickened subcutaneous fat layer in obese subjects significantly reduced the effective pressure transmitted to the brachial artery, which may explain why blood pressure overestimation occurs more frequently in obese subjects in noninvasive blood pressure measurement.
Leung, H; Kwan, P; Elger, C E
2006-08-01
Basic science studies of the human brain have supported the cortical representation of cardiovascular responses, including heart rate variability. Clinical observations of ictal bradyarrhythmia may be mechanistically explained by the influence of the central autonomic network, although the localization and lateralization issues need to be considered in the light of patterns of seizure spread, hand dominance, and presence of lesions. Ictal bradyarrhythmia also offers a mechanistic explanation of sudden unexpected death in epilepsy (SUDEP), though it may explain only some but not all cases of SUDEP. The missing links are (1) clinical evidence of common factors shared by patients with ictal bradyarrhythmia and patients who die from SUDEP, (2) evidence of arrhythmia as a risk factor for SUDEP from epidemiological studies, and, (3) determination of the importance of ictal bradyarrhythmia in SUDEP with respect to other proposed mechanisms including apnea and intrinsic cardiac abnormalities. There remains a need to review the seizure mechanisms in cases of SUDEP and to step up the amount of concurrent ECG/intracranial EEG analysis in both ictal bradyarrhythmia and SUDEP cases.
NASA Astrophysics Data System (ADS)
Purschke, Oliver; Dengler, Jürgen; Bruelheide, Helge; Chytrý, Milan; Jansen, Florian; Hennekens, Stephan; Jandt, Ute; Jiménez-Alfaro, Borja; Kattge, Jens; De Patta Pillar, Valério; Sandel, Brody; Winter, Marten
2015-04-01
The trait composition of plant communities is determined by abiotic, biotic and historical factors, but the importance of macro-climatic factors in explaining trait-environment relationships at the local scale remains unclear. Such knowledge is crucial for biogeographical and ecological theory but also relevant to devise management measures to mitigate the negative effects of climate change. To address these questions, an iDiv Working Group has established the first global vegetation-plot database (sPlot). sPlot currently contains ~700,000 plots from over 50 countries and all biomes, and is steadily growing. Approx. 70% of the most frequent species are represented by at least one trait in the global trait database TRY and gap-filled data will become available for the most common traits. We will give an overview about the structure and present content of sPlot in terms of spatial distribution, data properties and trait coverage. We will explain next steps and perspectives, present first cross-biome analyses of community-weighted mean traits and trait variability, and highlight some ecological questions that can be addressed with sPlot.
Volcanic calderas delineate biogeographic provinces among Yellowstone thermophiles.
Takacs-Vesbach, Cristina; Mitchell, Kendra; Jackson-Weaver, Olan; Reysenbach, Anna-Louise
2008-07-01
It has been suggested that the distribution of microorganisms should be cosmopolitan because of their enormous capacity for dispersal. However, recent studies have revealed that geographically isolated microbial populations do exist. Geographic distance as a barrier to dispersal is most often invoked to explain these distributions. Here we show that unique and diverse sequences of the bacterial genus Sulfurihydrogenibium exist in Yellowstone thermal springs, indicating that these sites are geographically isolated. Although there was no correlation with geographic distance or the associated geochemistry of the springs, there was a strong historical signal. We found that the Yellowstone calderas, remnants of prehistoric volcanic eruptions, delineate biogeographical provinces for the Sulfurihydrogenibium within Yellowstone (chi(2): 9.7, P = 0.002). The pattern of distribution that we have detected suggests that major geological events in the past 2 million years explain more of the variation in sequence diversity in this system than do contemporary factors such as habitat or geographic distance. These findings highlight the importance of historical legacies in determining contemporary microbial distributions and suggest that the same factors that determine the biogeography of macroorganisms are also evident among bacteria.
Benchmarking forensic mental health organizations.
Coombs, Tim; Taylor, Monica; Pirkis, Jane
2011-04-01
This paper describes the forensic mental health forums that were conducted as part of the National Mental Health Benchmarking Project (NMHBP). These forums encouraged participating organizations to compare their performance on a range of key performance indicators (KPIs) with that of their peers. Four forensic mental health organizations took part in the NMHBP. Representatives from these organizations attended eight benchmarking forums at which they documented their performance against previously agreed KPIs. They also undertook three special projects which explored some of the factors that might explain inter-organizational variation in performance. The inter-organizational range for many of the indicators was substantial. Observing this led participants to conduct the special projects to explore three factors which might help explain the variability - seclusion practices, delivery of community mental health services, and provision of court liaison services. The process of conducting the special projects gave participants insights into the practices and structures employed by their counterparts, and provided them with some important lessons for quality improvement. The forensic mental health benchmarking forums have demonstrated that benchmarking is feasible and likely to be useful in improving service performance and quality.
Rúa-Uribe, Guillermo L; Suárez-Acosta, Carolina; Chauca, José; Ventosilla, Palmira; Almanza, Rita
2013-09-01
Dengue fever is a major impact on public health vector-borne disease, and its transmission is influenced by entomological, sociocultural and economic factors. Additionally, climate variability plays an important role in the transmission dynamics. A large scientific consensus has indicated that the strong association between climatic variables and disease could be used to develop models to explain the incidence of the disease. To develop a model that provides a better understanding of dengue transmission dynamics in Medellin and predicts increases in the incidence of the disease. The incidence of dengue fever was used as dependent variable, and weekly climatic factors (maximum, mean and minimum temperature, relative humidity and precipitation) as independent variables. Expert Modeler was used to develop a model to better explain the behavior of the disease. Climatic variables with significant association to the dependent variable were selected through ARIMA models. The model explains 34% of observed variability. Precipitation was the climatic variable showing statistically significant association with the incidence of dengue fever, but with a 20 weeks delay. In Medellin, the transmission of dengue fever was influenced by climate variability, especially precipitation. The strong association dengue fever/precipitation allowed the construction of a model to help understand dengue transmission dynamics. This information will be useful to develop appropriate and timely strategies for dengue control.
The impact of socioeconomic factors on municipal solid waste generation in São Paulo, Brazil.
Vieira, Victor H Argentino de Morais; Matheus, Dácio R
2018-01-01
Social factors have not been sufficiently explored in municipal solid waste management studies. Latin America has produced even fewer studies with this approach; technical and economic investigations have prevailed. We explored the impacts of socioeconomic factors on municipal solid waste generation in Greater Sao Paulo, which includes 39 municipalities. We investigated the relations between municipal solid waste generation and social factors by Pearson's correlation coefficient. The Student's t-test (at p ← 0.01) proved significance, and further regression analysis was performed with significant factors. We considered 10 socioeconomic factors: population, rural population, density, life expectancy, education (secondary, high and undergraduate level), income per capita, inequality and human development. A later multicollinearity analysis resulted in the determination of inequality (r p = 0.625) and income per capita (r p = 0.607) as major drivers. The results showed the relevance of considering social aspects in municipal solid waste management and isolated inequality as an important factor in planning. Inequality must be used as a complementary factor to income, rather than being used exclusively. Inequality may explain differences of waste generation between areas with similar incomes because of consumption patterns. Therefore, unequal realities demand unequal measures to avoid exacerbation, for example, pay-as-you-throw policies instead of uniform fees. Unequal realities also highlight the importance of tiering policies beyond the waste sector, such as sustainable consumption.
Manderoos, Sirpa; Vaara, Mariitta; Karppi, Sirkka-Liisa; Aunola, Sirkka; Puukka, Pauli; Surakka, Jukka; Mälkiä, Esko
2018-04-26
The purpose of this cross-sectional study was to determine the relationships between agility, running speed, jumping height and length, body mass index, self-report pain in back and in lower extremities, personal factors as self-report health and fitness, and leisure time physical activity in physically inactive or active adult people. Altogether, 233 healthy subjects, 149 women (43.0 ± 7.3 years) and 84 men (44.0 ± 7.7 years), participated into study. Outcome measures were described in the International Classification of Functioning, Disability and Health domains. Multiple regression analysis showed that jumping length explained 24.6% and 15.3% of the variance associated with agility in women and men (adjusted R 2 = .246, p < .001; adjusted R 2 = .153, p = .001, respectively). Jumping length was the main determinant of agility among physically inactive or active women and men. The findings of this study strengthen opinion that the Agility Test for Adults demands also other physical and cognitive characteristics as measured now and their part explaining agility results may be relatively great. We suggest that perception and decision making explain for a great part in agility. It seems that body mass index does not play important role in agility, but physical inactivity can explain or increase the decline of agility. Also, various biological mechanisms in aging process can be linked to the deterioration of capacity of agility. Copyright © 2018 John Wiley & Sons, Ltd.
The most important "factor" in producing clubhead speed in golf.
Joyce, Christopher
2017-10-01
Substantial experiential research into x-factor, and to a lesser extent crunch-factor has been undertaken with the aim of increasing clubhead speed. However, a direct comparison of the golf swing kinematics associated with each 'factor' has not, and possible differences when using a driver compared to an iron. Fifteen low handicap male golfers who displayed a modern swing had their golf swing kinematic data measured when hitting their own driver and five-iron, using a 10-camera motion analysis system operating at 250Hz. Clubhead speed was collected using a validated launch monitor. No between-club differences in x-factor and crunch-factor existed. Correlation analyses revealed within-club segment (trunk and lower trunk) interaction was different for the driver, compared to the five-iron, and that a greater number of kinematic variables associated with x-factor, compared to crunch-factor were shown to be correlated with faster clubhead speeds. This was further explained in the five-iron regression model, where a significant amount of variance in clubhead speed was associated with increased lower trunk x-factor stretch, and reduced trunk lateral bending. Given that greens in regulation was shown to be the strongest correlated variable with PGA Tour earnings (1990-2004), the findings suggests a link to player performance for approach shots. These findings support other empiric research into the importance of x-factor as well as anecdotal evidence on how crunch-factor can negatively affect clubhead speed. Copyright © 2017 Elsevier B.V. All rights reserved.
Molecular insight in gastric cancer induction: an overview of cancer stemness genes.
Akhavan-Niaki, Haleh; Samadani, Ali Akbar
2014-04-01
Gastric cancer is one of the most outgoing human cancers in the world. Two main functional types were described: Intestinal adenocarcinoma and diffuse one. The most important purpose of this review is to analyze and investigate the main genetic factors involved in tumorogenesis of stomach and the molecular mechanism of their expression regulation alongside with the importance of cancer stem cells and their relationship with gastric cancer. It is evident that proper diagnosis of molecular case of cancer may lead to absolute treatment and at least reduction in the disease severity. However, stemness factors such as Sox2, Oct3/4, and Nanog were related with induced pluripotent stem cells, proposing a correlation between these stemness factors and cancer stem cells. Moreover, aberrant induction by Helicobacter pylori of the intestinal-specific homeobox transcription factors, CDX1 and CDX2, also plays an important role in this modification. There are some genes which are directly activated by CDX1 in gastric cancer and distinguished stemness-related reprogramming factors like SALL4 and KLF5. Correspondingly, we also aimed to present the main important epigenetic changes such as DNA methylation, histone modification, and chromatin modeling of stemness genes in disease development. Remarkably, a better understanding of molecular bases of cancer may lead to novel diagnostic, therapeutic, and preventive approaches by some genetic and epigenetic changes such as gene amplifications, gene silencing by DNA methylation, losses of imprinting, LOH, and mutations. Consequently, genome-wide searches of gene expression are widely important for surveying the proper mechanisms of cancer emergence and development. Conspicuously, this review explains an outline of the molecular mechanism and new approaches in gastric cancer.
Scheper, Jeroen; Reemer, Menno; van Kats, Ruud; Ozinga, Wim A; van der Linden, Giel T J; Schaminée, Joop H J; Siepel, Henk; Kleijn, David
2014-12-09
Evidence for declining populations of both wild and managed bees has raised concern about a potential global pollination crisis. Strategies to mitigate bee loss generally aim to enhance floral resources. However, we do not really know whether loss of preferred floral resources is the key driver of bee decline because accurate assessment of host plant preferences is difficult, particularly for species that have become rare. Here we examine whether population trends of wild bees in The Netherlands can be explained by trends in host plants, and how this relates to other factors such as climate change. We determined host plant preference of bee species using pollen loads on specimens in entomological collections that were collected before the onset of their decline, and used atlas data to quantify population trends of bee species and their host plants. We show that decline of preferred host plant species was one of two main factors associated with bee decline. Bee body size, the other main factor, was negatively related to population trend, which, because larger bee species have larger pollen requirements than smaller species, may also point toward food limitation as a key factor driving wild bee loss. Diet breadth and other potential factors such as length of flight period or climate change sensitivity were not important in explaining twentieth century bee population trends. These results highlight the species-specific nature of wild bee decline and indicate that mitigation strategies will only be effective if they target the specific host plants of declining species.
Johansson, Elin; Leijon, Ola; Falkstedt, Daniel; Farah, Ahmed; Hemmingsson, Tomas
2012-10-01
The association between level of education and disability pension (DP) is well known. Earlier studies have investigated the importance of early life factors and work characteristics but not in combination. The aim of this study was to investigate the association between level of education and DP among Swedish middle-aged working men and to what extent such an association can be explained by factors measured in late adolescence and work characteristics in adulthood. Information about IQ, health-related lifestyle factors, psychiatric and musculoskeletal diagnoses was obtained from the 1969 conscription cohort, consisting of 49,321 Swedish men. Data collected when subjects were 18-20 years of age were combined with national register-based information about level of education, job control and physical strain at work in adulthood, and information about DP between 1991 and 2002. There was a strong graded association between level of education and DP. Those with the lowest level of education had a four times greater probability of having DP as compared with those with the highest level. In multivariable analyses, factors measured in late adolescence, IQ in particular, attenuated the association more than work-related characteristics in adulthood. The authors found an association between level of education and DP among Swedish middle-aged working men. A large part of the association was explained by factors measured in late adolescence, IQ in particular, and somewhat less by work characteristics measured in adulthood. Level of education remained as a significant predictor of DP in middle age after full adjustment.
Scheper, Jeroen; Reemer, Menno; van Kats, Ruud; Ozinga, Wim A.; van der Linden, Giel T. J.; Schaminée, Joop H. J.; Siepel, Henk; Kleijn, David
2014-01-01
Evidence for declining populations of both wild and managed bees has raised concern about a potential global pollination crisis. Strategies to mitigate bee loss generally aim to enhance floral resources. However, we do not really know whether loss of preferred floral resources is the key driver of bee decline because accurate assessment of host plant preferences is difficult, particularly for species that have become rare. Here we examine whether population trends of wild bees in The Netherlands can be explained by trends in host plants, and how this relates to other factors such as climate change. We determined host plant preference of bee species using pollen loads on specimens in entomological collections that were collected before the onset of their decline, and used atlas data to quantify population trends of bee species and their host plants. We show that decline of preferred host plant species was one of two main factors associated with bee decline. Bee body size, the other main factor, was negatively related to population trend, which, because larger bee species have larger pollen requirements than smaller species, may also point toward food limitation as a key factor driving wild bee loss. Diet breadth and other potential factors such as length of flight period or climate change sensitivity were not important in explaining twentieth century bee population trends. These results highlight the species-specific nature of wild bee decline and indicate that mitigation strategies will only be effective if they target the specific host plants of declining species. PMID:25422416
Predicting the scope of practice of family physicians.
Wong, Eric; Stewart, Moira
2010-06-01
To identify factors that are associated with the scope of practice of FPs and GPs who have office-based practices. Secondary univariable and multivariable analyses of cross-sectional data from the 2001 National Family Physician Workforce Survey conducted by the College of Family Physicians of Canada. Canada. General community of FPs and GPs who spent most of their clinical time in office settings. Demographic characteristics and scope of practice score (SPS), which was the number of 12 selected medical services provided by office-based FPs and GPs. The multivariable model explained 35.1% of the variation in the SPS among participants. Geographic factors of provincial division and whether or not the population served was rural explained 30.5% of the variation in the SPS. Male physician sex, younger physician age, being in group practice, greater access to hospital beds, less access to specialists, main practice setting of an academic teaching unit, mixed method physician payment, additional structured postresidency training, and greater number of different types of allied health professionals in the main practice setting were also associated with higher SPSs. Geographic factors were the strongest determinants of scope of practice; physician-related factors, availability of health care resources to the main practice setting, and practice organization factors were weaker determinants. It is important to understand how and why geographic factors influence scope of practice, and whether a broad scope of practice independent of population needs benefits the population. This study supports primary care renewal efforts that use mixed payment systems, incorporate allied health care professionals into family and general practices, and foster group practices.
Fouchet, David; Leblanc, Guillaume; Sauvage, Frank; Guiserix, Micheline; Poulet, Hervé; Pontier, Dominique
2009-01-01
Background In natural cat populations, Feline Immunodeficiency Virus (FIV) is transmitted through bites between individuals. Factors such as the density of cats within the population or the sex-ratio can have potentially strong effects on the frequency of fight between individuals and hence appear as important population risk factors for FIV. Methodology/Principal Findings To study such population risk factors, we present data on FIV prevalence in 15 cat populations in northeastern France. We investigate five key social factors of cat populations; the density of cats, the sex-ratio, the number of males and the mean age of males and females within the population. We overcome the problem of dependence in the infective status data using sexually-structured dynamic stochastic models. Only the age of males and females had an effect (p = 0.043 and p = 0.02, respectively) on the male-to-female transmission rate. Due to multiple tests, it is even likely that these effects are, in reality, not significant. Finally we show that, in our study area, the data can be explained by a very simple model that does not invoke any risk factor. Conclusion Our conclusion is that, in host-parasite systems in general, fluctuations due to stochasticity in the transmission process are naturally very large and may alone explain a larger part of the variability in observed disease prevalence between populations than previously expected. Finally, we determined confidence intervals for the simple model parameters that can be used to further aid in management of the disease. PMID:19888418
2012-01-01
Background In spite of a detailed and nation-wide legislation frame, there exist large cantonal disparities in consumed quantities of health care services in Switzerland. In this study, the most important factors of influence causing these regional disparities are determined. The findings can also be productive for discussing the containment of health care consumption in other countries. Methods Based on the literature, relevant factors that cause geographic disparities of quantities and costs in western health care systems are identified. Using a selected set of these factors, individual panel econometric models are calculated to explain the variation of the utilization in each of the six largest health care service groups (general practitioners, specialist doctors, hospital inpatient, hospital outpatient, medication, and nursing homes) in Swiss mandatory health insurance (MHI). The main data source is 'Datenpool santésuisse', a database of Swiss health insurers. Results For all six health care service groups, significant factors influencing the utilization frequency over time and across cantons are found. A greater supply of service providers tends to have strong interrelations with per capita consumption of MHI services. On the demand side, older populations and higher population densities represent the clearest driving factors. Conclusions Strategies to contain consumption and costs in health care should include several elements. In the federalist Swiss system, the structure of regional health care supply seems to generate significant effects. However, the extent of driving factors on the demand side (e.g., social deprivation) or financing instruments (e.g., high deductibles) should also be considered. PMID:22413884
Rai, Dheeraj; Zitko, Pedro; Jones, Kelvyn; Lynch, John; Araya, Ricardo
2013-03-01
The prevalence and correlates of depression vary across countries. Contextual factors such as country-level income or income inequalities have been hypothesised to contribute to these differences. To investigate associations of depression with socioeconomic factors at the country level (income inequality, gross national income) and individual (education, employment, assets and spending) level, and to investigate their relative contribution in explaining the cross-national variation in the prevalence of depression. Multilevel study using interview data of 187 496 individuals from 53 countries participating in the World Health Organization World Health Surveys. Depression prevalence varied between 0.4 and 15.7% across countries. Individual-level factors were responsible for 86.5% of this variance but there was also reasonable variation at the country level (13.5%), which appeared to increase with decreasing economic development of countries. Gross national income or country-level income inequality had no association with depression. At the individual level, fewer material assets, lower education, female gender, economic inactivity and being divorced or widowed were associated with increased odds of depression. Greater household spending, unlike material assets, was associated with increasing odds of depression (adjusted analysis). The variance of depression prevalence attributable to country-level factors seemed to increase with decreasing economic development of countries. However, country-level income inequality or gross national income explained little of this variation, and individual-level factors appeared more important than contextual factors as determinants of depression. The divergent relationship of assets and spending with depression emphasise that different socioeconomic measures are not interchangeable in their associations with depression.
Suicidal and nonsuicidal adolescents: different factors contribute to self-esteem.
Grøholt, Berit; Ekeberg, Oivind; Wichstrøm, Lars; Haldorsen, Tor
2005-10-01
Some risk and protective factors differ in their importance to suicidal and nonsuicidal people. In this research we explore the cross-sectional differences between risk factors among suicidal adolescents and nonsuicidal adolescents by focusing on self-esteem. Sixty-five suicidal and 390 nonsuicidal adolescents were compared on Harter's Self-Perceived Profile for Adolescents, self-concept stability, seeking support, loneliness, and depression. Self-concept stability, loneliness, and peer support correlated differently with self-esteem. In multivariate regression analyses, variance in self-esteem was explained by depression and loneliness, and among nonsuicidal adolescents also by self-concept stability, support, and competencies. Loneliness and self-concept stability related differently to self-esteem in suicidal and nonsuicidal adolescents. When the aim is to enhance self-esteem, this difference may delineate suicidal subgroups that need special interventions.
Juaneda-Ayensa, Emma; Clavel San Emeterio, Mónica; González-Menorca, Carlos
2017-01-01
From an Organizational Behavior perspective, it is important to recognize the links generated between individuals and the organization that encourage a desire for permanence. After more than a half century of research, Organizational Commitment remains one of the open questions in the Psychology of Organizations. It is considered an essential factor for explaining individual behavior in the organization such as satisfaction, turnover intention, or loyalty. In this paper, we analyze different contributions regarding the nature of the bond between the individual and the organization. Taking into account the peculiarities of Non-profit Organizations, we present different interpretation for later validation, comparing results from the Confirmatory Factor Analysis of the four models obtained using exploratory factor analysis, both conducted on a sample of 235 members of Non-profit Organizations.
Reading among diverse DHH learners: what, how, and for whom?
Easterbrooks, Susan R; Lederberg, Amy R; Antia, Shirin; Schick, Brenda; Kushalnagar, Poorna; Webb, Mi-Young; Branum-Martin, Lee; Connor, Carol McDonald
2015-01-01
Students whO are deaf and hard of hearing (DHH) face challenges in learning to read. Much has been written about the relative importance of the different factors associated with success in reading, but these factors are disputed within the literature on DHH readers. The Center on Literacy and Deafness, funded by the Institute of Education Sciences, is engaged in a nationwide project to identify child-by-instruction interactions related to instructional factors that are malleable within the classroom context. In the present article, the authors describe the project, present the conceptual model on which it is based, explain the processes and procedures used to choose assessment tools, and discuss their theoretical view of how reading and instruction might differ based on an individual student's language and level of functional hearing.
Lum, Terry Y S; Yan, Elsie C W; Ho, Andy H Y; Shum, Michelle H Y; Wong, Gloria H Y; Lau, Mandy M Y; Wang, Junfang
2016-11-01
The experience and practice of filial piety have evolved in modern Chinese societies, and existing measures fail to capture these important changes. Based on a conceptual analysis on current literature, 42 items were initially compiled to form a Contemporary Filial Piety Scale (CFPS), and 1,080 individuals from a representative sample in Hong Kong were surveyed. Principal component analysis generated a 16-item three-factor model: Pragmatic Obligations (Factor 1; 10 items), Compassionate Reverence (Factor 2; 4 items), and Family Continuity (Factor 3; 2 items). Confirmatory factor analysis revealed strong factor loadings for Factors 1 and 2, while removing Factor 3 and conceptually duplicated items increased total variance explained from 58.02% to 60.09% and internal consistency from .84 to .88. A final 10-item two-factor structure model was adopted with a goodness of fit of 0.95. The CFPS-10 is a data-driven, simple, and efficient instrument with strong psychometric properties for assessing contemporary filial piety. © The Author(s) 2015.
2011-01-01
Background Infection processes consist of a sequence of steps, each critical for the interaction between host and parasite. Studies of host-parasite interactions rarely take into account the fact that different steps might be influenced by different factors and might, therefore, make different contributions to shaping coevolution. We designed a new method using the Daphnia magna - Pasteuria ramosa system, one of the rare examples where coevolution has been documented, in order to resolve the steps of the infection and analyse the factors that influence each of them. Results Using the transparent Daphnia hosts and fluorescently-labelled spores of the bacterium P. ramosa, we identified a sequence of infection steps: encounter between parasite and host; activation of parasite dormant spores; attachment of spores to the host; and parasite proliferation inside the host. The chances of encounter had been shown to depend on host genotype and environment. We tested the role of genetic and environmental factors in the newly described activation and attachment steps. Hosts of different genotypes, gender and species were all able to activate endospores of all parasite clones tested in different environments; suggesting that the activation cue is phylogenetically conserved. We next established that parasite attachment occurs onto the host oesophagus independently of host species, gender and environmental conditions. In contrast to spore activation, attachment depended strongly on the combination of host and parasite genotypes. Conclusions Our results show that different steps are influenced by different factors. Host-type-independent spore activation suggests that this step can be ruled out as a major factor in Daphnia-Pasteuria coevolution. On the other hand, we show that the attachment step is crucial for the pronounced genetic specificities of this system. We suggest that this one step can explain host population structure and could be a key force behind coevolutionary cycles. We discuss how different steps can explain different aspects of the coevolutionary dynamics of the system: the properties of the attachment step, explaining the rapid evolution of infectivity and the properties of later parasite proliferation explaining the evolution of virulence. Our study underlines the importance of resolving the infection process in order to better understand host-parasite interactions. PMID:21342515
Robertson, Ellen P; Fletcher, Robert J; Austin, James D
2017-07-01
The decision to disperse or remain philopatric between breeding seasons has important implications for both ecology and evolution, including the potential for carry-over effects, where an individual's previous history affects its current performance. Carry-over effects are increasingly documented although underlying mechanisms remain unclear. Here we test for potential carry-over effects and their mechanisms by uniting hypotheses for the causes and consequences of habitat selection and dispersal across space and time. We linked hypotheses regarding different types of factors and information (environmental conditions, personal and public information) predicted to impact reproductive success and dispersal for an endangered, wetland-dependent bird, the snail kite (Rostrhamus sociabilis plumbeus). To do so, we coupled structural equation modelling with 20 years of mark-recapture and nesting data across the breeding range of this species to isolate potential direct and indirect effects of these factors. We found that water depth at nest sites explained subsequent emigration rates via an indirect path through the use of personal, not public, information. Importantly, we found that these dispersers tended to initiate nests later the following breeding season. This pattern explained a phenological mismatch of nesting with hydrological conditions, whereby immigrants tended to nest later, late nesters tended to experience lower water depths, higher nest failure occurred at lower water depths and higher nest failure explained subsequent breeding dispersal. These results identified a novel potential mechanism for carry-over effects: a phenological mismatch with environmental conditions (water depth) that occurred potentially due to time costs of dispersal. Our results also highlighted a substantial benefit of philopatry - earlier initiation of reproduction - which allows philopatric individuals to better coincide with environmental conditions that are beneficial for successful reproduction. These results have implications for our mechanistic understanding and prediction of carryover effects, and emphasize that local conservation strategies, such as water management, can explain future demography at distant sites connected through dispersal. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.
Li, Siyue; Zhang, Quanfa
2011-06-15
Water samples were collected for determination of dissolved trace metals in 56 sampling sites throughout the upper Han River, China. Multivariate statistical analyses including correlation analysis, stepwise multiple linear regression models, and principal component and factor analysis (PCA/FA) were employed to examine the land use influences on trace metals, and a receptor model of factor analysis-multiple linear regression (FA-MLR) was used for source identification/apportionment of anthropogenic heavy metals in the surface water of the River. Our results revealed that land use was an important factor in water metals in the snow melt flow period and land use in the riparian zone was not a better predictor of metals than land use away from the river. Urbanization in a watershed and vegetation along river networks could better explain metals, and agriculture, regardless of its relative location, however slightly explained metal variables in the upper Han River. FA-MLR analysis identified five source types of metals, and mining, fossil fuel combustion, and vehicle exhaust were the dominant pollutions in the surface waters. The results demonstrated great impacts of human activities on metal concentrations in the subtropical river of China. Copyright © 2011 Elsevier B.V. All rights reserved.
Heterogeneity in cord blood DHA concentration: towards an explanation.
Muhlhausler, B S; Gibson, R A; Yelland, L N; Makrides, M
2014-10-01
This paper aimed to identify the dietary and non-dietary determinants of docosahexaenoic acid (DHA) levels in umbilical cord blood at delivery. DHA was measured in cord blood plasma phospholipids of 1571 participants from the DOMInO (DHA to Optimize Mother Infant Outcome) randomized controlled trial. Socioeconomic, lifestyle and clinical data relating to the mother and current pregnancy were obtained from all women and their relationships with cord blood DHA assessed. DHA concentrations in the cord plasma phospholipids at delivery covered a 3-4 fold range in both control and DHA groups. The total number of DHA-rich intervention supplement capsules consumed over the course of pregnancy and gestational age at delivery individually explained 21% and 16% respectively of the variation in DHA abundance in the cord blood plasma phospholipids at delivery, but no other clinical or life-style factors explored in this study could account for >2% of the variation. Indeed, more than 65% of the variation remained unaccounted for even when all factors were included in the analysis. These data suggest that factors other than maternal DHA intake have an important role in determining cord blood DHA concentrations at delivery, and may at least partially explain the variation in the response of infants to maternal DHA supplementation reported in published trials. Copyright © 2014 Elsevier Ltd. All rights reserved.
Sundara, Megha; Demuth, Katherine; Kuhl, Patricia K
2011-02-01
Two-year-olds produce third person singular -s more accurately on verbs in sentence-final position as compared with verbs in sentence-medial position. This study was designed to determine whether these sentence-position effects can be explained by perceptual factors. For this purpose, the authors compared 22- and 27-month-olds' perception and elicited production of third person singular -s in sentence-medial versus-final position. The authors assessed perception by measuring looking/listening times to a 1-screen display of a cartoon paired with a grammatical versus an ungrammatical sentence (e.g., She eats now vs. She eat now). Children at both ages demonstrated sensitivity to the presence/absence of this inflectional morpheme in sentence-final, but not sentence-medial, position. Children were also more accurate at producing third person singular -s sentence finally, and production accuracy was predicted by vocabulary measures as well as by performance on the perception task. These results indicate that children's more accurate production of third person singular -s in sentence-final position cannot be explained by articulatory factors alone but that perceptual factors play an important role in accounting for early patterns of production. The findings also indicate that perception and production of inflectional morphemes may be more closely related than previously thought.
Mehlum, Ingrid Sivesind; Kristensen, Petter; Kjuus, Helge; Wergeland, Ebba
2008-08-01
The aim of this study was to quantify socioeconomic inequalities in low-back pain, neck-shoulder pain, and arm pain in the general working population in Oslo and to examine the impact of job characteristics on these inequalities. All economically active 30-, 40-, and 45-year-old persons who attended the Oslo health study in 2000-2001 and answered questions on physical job demands, job autonomy, and musculoskeletal pain were included (N=7293). Occupational class was used as an indicator of socioeconomic status. The lower occupational classes were compared with higher grade professionals, and prevalences, prevalence ratios, prevalence differences, and population attributable fractions were calculated. There were marked, stepwise socioeconomic gradients for musculoskeletal pain, steeper for the men than for the women. The relative differences (prevalence ratios) were larger for low-back pain and arm pain than for neck-shoulder pain. The absolute differences (prevalence differences) were the largest for low-back pain. Physical job demands explained a substantial proportion of the absolute occupational class inequalities in low-back pain, while job autonomy was more important in explaining the inequalities in neck-shoulder pain and arm pain. The estimated population attributable fractions supported the impact of job characteristics at the working population level, especially for low-back pain. In this cross-sectional study, physical job demands and job autonomy explained a substantial proportion of occupational class inequalities in self-reported musculoskeletal pain in the working population in Oslo. This finding indicates that the workplace may be an important arena for preventive efforts to reduce socioeconomic inequalities in musculoskeletal pain.
NASA Astrophysics Data System (ADS)
Ahlgren, Joakim; Grimvall, Anders; Omstedt, Anders; Rolff, Carl; Wikner, Johan
2017-06-01
Hypoxia and oxygen deficient zones are expanding worldwide. To properly manage this deterioration of the marine environment, it is important to identify the causes of oxygen declines and the influence of anthropogenic activities. Here, we provide a study aiming to explain the declining oxygen levels in the deep waters of the Bothnian Sea over the past 20 years by investigating data from environmental monitoring programmes. The observed decline in oxygen concentrations in deep waters was found to be primarily a consequence of water temperature increase and partly caused by an increase in dissolved organic carbon (DOC) in the seawater (R2Adj. = 0.83) as well as inflow from the adjacent sea basin. As none of the tested eutrophication-related predictors were significant according to a stepwise multiple regression, a regional increase in nutrient inputs to the area is unlikely to explain a significant portion of the oxygen decline. Based on the findings of this study, preventing the development of anoxia in the deep water of the Bothnian Sea is dependent on the large-scale measures taken to reduce climate change. In addition, the reduction of the nutrient load to the Baltic Proper is required to counteract the development of hypoxic and phosphate-rich water in the Baltic Proper, which can form deep water in the Bothnian Sea. The relative importance of these sources to oxygen consumption is difficult to determine from the available data, but the results clearly demonstrate the importance of climate related factors such as temperature, DOC and inflow from adjacent basins for the oxygen status of the sea.
Gibbs, Bethany Barone; Brancati, Frederick L; Chen, Haiying; Coday, Mace; Jakicic, John M; Lewis, Cora E; Stewart, Kerry J; Clark, Jeanne M
2014-05-01
Because lifestyle-induced improvements in cardiovascular risk factors vary substantially across individuals with type 2 diabetes, we investigated the extent to which increases in fitness explain cardiovascular risk factor improvements independent of weight loss in a lifestyle intervention. We studied 1-year changes in Look AHEAD, a randomized trial comparing an intensive lifestyle intervention (ILI) to a diabetes support and education (DSE) control group in adults with type 2 diabetes. Assessments included weight, fitness, blood pressure (BP), glucose, HbA1c, and lipids. We evaluated the effects of changes in weight and fitness on changes in cardiovascular risk factors by study arm, using R (2) from multiple linear regression. Analyses included participants with fitness data at baseline and 1-year (n = 4408; 41% male, 36% non-white; mean age 58.7 ± 6.8 years). Weight change alone improved R (2) for explaining changes in risk factors up to 8.2% in ILI and 1.7% in DSE. Fitness change alone improved R (2) up to 3.9% in ILI and 0.8% in DSE. After adjusting for weight change, fitness was independently associated (p < 0.05) with improvements in R (2) for glucose (+0.7%), HbA1c (+1.1%), high-density lipoprotein (HDL) cholesterol (+0.4%), and triglycerides (+0.2%) in ILI and diastolic BP (+0.3%), glucose (+0.3%), HbA1c (+0.4%), and triglycerides (+0.1%) in DSE. Taken together, weight and fitness changes explained from 0.1-9.3% of the variability in cardiovascular risk factor changes. Increased fitness explained statistically significant but small improvements in several cardiovascular risk factors beyond weight loss. Further research identifying other factors that explain cardiovascular risk factor change is needed.
Lo, C C; Globetti, G
1995-01-01
The purpose of this study was to examine how selected internal and external control variables influence lifetime use, frequency of use, and cessation of use of marijuana. The internal control factor, comprising the variables 1) perceived risk of marijuana use and 2) attitudes toward prohibition of marijuana use, refers to a built-in personal tendency toward conventionality. The external control factor refers to social-environmental forces which discourage marijuana use. External control is indicated by factors including the number of extra-curricular activities in which an individual is involved; place of residence; the availability of marijuana; peer attitudes toward marijuana use; the number of an individual's friends who use marijuana; and the number of occasions on which an individual has observed others using marijuana. The study's results show that both internal and external control factors are significant predictors of the frequency of marijuana use. The external control factor, however, plays a more important role in explaining lifetime marijuana use and cessation of marijuana use.
And now, from the company that brought you the seven-eyed trout: Risk communication in action
DOE Office of Scientific and Technical Information (OSTI.GOV)
Durbin, M.E.; Klein, S.H.; Molony, S.T.
1992-01-01
Risk communication is a growing specialty field in communication that draws from well-established principles of sociology and psychology. It is a way to communicate with potentially hostile audiences about sensitive environmental, safety, and health issues they face. This paper explains the most important principles of risk communication and discusses audience analyses, perceptions of risk (outrage factors), and risk comparisons. These principles are applied to a risk communication issue in a fictitious community.
Considering theories of aggression in an emergency department context.
Ferns, Terry
2007-10-01
Internationally literature emphasises concern regarding the phenomenon of violence and aggression within the emergency field. This paper emphasises the important role education and training may play in reducing the risk of staff being exposed to violent or aggressive experiences. Furthermore, the paper emphasises, explores and discusses well recognised theories relating to aggression development. These theories can be used to explain both organisational strategies designed to minimise aggression in the emergency department and situational factors contributing to the development of aggressive interactions.
Menendez-Baceta, Gorka; Aceituno-Mata, Laura; Reyes-García, Victoria; Tardío, Javier; Salpeteur, Matthieu; Pardo-de-Santayana, Manuel
2015-02-23
Previous research suggests that the use of medicinal plants by a given group is mainly driven by biological variables such as the chemical composition or the ecological distribution of plants. However, other studies highlight the importance of cultural aspects such as the curative meaning given to a plant, beliefs, religion or the historical context. Such aspects could play an important role in the use, diffusion or even in the effectiveness of a plant remedy. Fieldwork consisted of 233 orally consented semi-structured interviews with 178 informants about medicinal uses of plants. Interviews were conducted in four historically and geographycally delimited regions of Alava and Biscay with similar environmental conditions but different sociolinguistic backgrounds: two regions were Basque- and two Spanish-speaking. Data were structured in use-reports. A Between Class Analysis was conducted to assess the intercultural and intracultural variability of medicinal plants knowledge. The results show the existence of four clearly different medicinal ethnofloras. While the four ethnofloras share remedies widely distributed through the territory, each of them also includes remedies that are only shared among closely related communities. The ecological availability and chemical composition of the plants may explain why there are widely used plant remedies. On the contrary, the distribution of the locally shared remedies matches up with the cultural heterogeneity of the territory, so cultural factors, such as, language, social networks or the meaning response of the plants seem to explain the use of many traditional plant remedies. In Addition, we also found that Basque speaking territories show higher knowledge levels than Spanish speaking territories. In this sense, the development and reinforcement of Basque identity by Basque nationalism seems to have contributed to maintain the traditional knowledge in the Basque speaking regions. Despite the fact that pharmacological effectiveness and ecological availability are usually considered as the main variables that shape the traditional use of medicinal plants, our results suggest that cultural factors can be at least as important as ecological and chemical factors. In fact, differences in language, in the cultural meaning of the plants, in the context related to cultural identities, and in social networks seem to play a fundamental role in the use and diffusion and maintenance or erosion of traditional knowledge about medicinal plants in the study area. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Mahesh, S; Leelambika, M; Jaheer, Md; Anithakumari, A M; Sathyanarayana, N
2016-03-01
Mucuna pruriens is a well-recognized agricultural and horticultural crop with important medicinal use. However, antinutritional factors in seed and adverse morphological characters have negatively affected its cultivation. To elucidate the genetic control of agronomic traits, an intraspecific genetic linkage map of Indian M. pruriens has been developed based on amplified fragment length polymorphism (AFLP) markers using 200 F₂ progenies derived from a cross between wild and cultivated genotypes. The resulting linkage map comprised 129 AFLP markers dispersed over 13 linkage groups spanning a total distance of 618.88 cM with an average marker interval of 4.79 cM. For the first time, three QTLs explaining about 6.05-14.77% of the corresponding total phenotypic variation for three quantitative (seed) traits and, eight QTLs explaining about 25.96% of the corresponding total phenotypic variation for three qualitative traits have been detected on four linkage groups. The map presented here will pave a way for mapping of genes/QTLs for the important agronomic and horticultural traits contrasting between the parents used in this study.
Identification and its vicissitudes.
Etchegoyen, R H
1985-01-01
This paper attempts to understand the vicissitudes of identification within the co-ordinates of narcissism and the object relation. Firstly the dialectic pair primary identification/secondary identification are studied, and primary narcissism is suggested as the hypothesis which best explains them. The complex identification processes in the primary scene are considered next and the importance of the introjection of the oedipal parents for the formation of the superego is underlined. The importance of the structuring function of the introjection and projection mechanisms becomes embodied in the concept of projective identification, which comes to question the postulate of primary narcissism. The theory of projective-introjective identification is an extremely powerful instrument for explaining phenomena, however it obliges one to accept that the first introjections are radically different from the others. They have nothing to do with mourning but rather with primitive mechanisms which question the subject/object polarity and, so this author believes, spring basically from envy. Lastly, it is maintained that envy and libido are factors of a dialectic from which the object relation and the earliest processes of identification, previous to the Oedipus complex, proceed at one and the same time.
Shaik, Sadiq S; Soltau, Thomas D; Chaturvedi, Gaurav; Totapally, Balagangadhar; Hagood, James S; Andrews, William W; Athar, Mohammad; Voitenok, Nikolai N; Killingsworth, Cheryl R; Patel, Rakesh P; Fallon, Michael B; Maheshwari, Akhil
2009-02-27
CXC chemokines with a glutamate-leucine-arginine (ELR) tripeptide motif (ELR(+) CXC chemokines) play an important role in leukocyte trafficking into the tissues. For reasons that are not well elucidated, circulating leukocytes are recruited into the tissues mainly in small vessels such as capillaries and venules. Because ELR(+) CXC chemokines are important mediators of endothelial-leukocyte interaction, we compared chemokine expression by microvascular and aortic endothelium to investigate whether differences in chemokine expression by various endothelial types could, at least partially, explain the microvascular localization of endothelial-leukocyte interaction. Both in vitro and in vivo models indicate that ELR(+) CXC chemokine expression is higher in microvascular endothelium than in aortic endothelial cells. These differences can be explained on the basis of the preferential activation of endothelial chemokine production by low intensity shear stress. Low shear activated endothelial ELR(+) CXC chemokine production via cell surface heparan sulfates, beta(3)-integrins, focal adhesion kinase, the mitogen-activated protein kinase p38beta, mitogen- and stress-associated protein kinase-1, and the transcription factor.
Individual-Area Relationship Best Explains Goose Species Density in Wetlands
Prins, Herbert H. T.; Cao, Lei; de Boer, Willem Fred
2015-01-01
Explaining and predicting animal distributions is one of the fundamental objectives in ecology and conservation biology. Animal habitat selection can be regulated by top-down and bottom-up processes, and is mediated by species interactions. Species varying in body size respond differently to top-down and bottom-up determinants, and hence understanding these allometric responses to those determinants is important for conservation. In this study, using two differently sized goose species wintering in the Yangtze floodplain, we tested the predictions derived from three different hypotheses (individual-area relationship, food resource and disturbance hypothesis) to explain the spatial and temporal variation in densities of two goose species. Using Generalized Linear Mixed Models with a Markov Chain Monte Carlo technique, we demonstrated that goose density was positive correlated with patch area size, suggesting that the individual area-relationship best predicts differences in goose densities. Moreover, the other predictions, related to food availability and disturbance, were not significant. Buffalo grazing probably facilitated greater white-fronted geese, as the number of buffalos was positively correlated to the density of this species. We concluded that patch area size is the most important factor determining the density of goose species in our study area. Patch area size is directly determined by water levels in the Yangtze floodplain, and hence modifying the hydrological regimes can enlarge the capacity of these wetlands for migratory birds. PMID:25996502
Numerical simulation model of hyperacute/acute stage white matter infarction.
Sakai, Koji; Yamada, Kei; Oouchi, Hiroyuki; Nishimura, Tsunehiko
2008-01-01
Although previous studies have revealed the mechanisms of changes in diffusivity (apparent diffusion coefficient [ADC]) in acute brain infarction, changes in diffusion anisotropy (fractional anisotropy [FA]) in white matter have not been examined. We hypothesized that membrane permeability as well as axonal swelling play important roles, and we therefore constructed a simulation model using random walk simulation to replicate the diffusion of water molecules. We implemented a numerical diffusion simulation model of normal and infarcted human brains using C++ language. We constructed this 2-pool model using simple tubes aligned in a single direction. Random walk simulation diffused water. Axon diameters and membrane permeability were then altered in step-wise fashion. To estimate the effects of axonal swelling, axon diameters were changed from 6 to 10 microm. Membrane permeability was altered from 0% to 40%. Finally, both elements were combined to explain increasing FA in the hyperacute stage of white matter infarction. The simulation demonstrated that simple water shift into the intracellular space reduces ADC and increases FA, but not to the extent expected from actual human cases (ADC approximately 50%; FA approximately +20%). Similarly, membrane permeability alone was insufficient to explain this phenomenon. However, a combination of both factors successfully replicated changes in diffusivity indices. Both axonal swelling and reduced membrane permeability appear important in explaining changes in ADC and FA based on eigenvalues in hyperacute-stage white matter infarction.
Petit, L.J.; Petit, D.R.; Petit, K.E.; Fleming, W.J.
1990-01-01
We studied foraging ecology of Prothonotary Warblers (Protonotaria citrea) over four breeding seasons to determine if this species exhibited sex-specific or temporal variation in foraging behavior. Significant differences between sexes during the prenestling period were found for foraging height and substrate height (foraging method, plant species/substrate, perch diameter, horizontal location from trunk, and prey location were not significantly different). During the nestling period, this divergence between sexes was evident for foraging height, substrate height, substrate / tree species, and prey location. Additionally, male warblers significantly altered their behavior for all seven foraging variables between the two periods, whereas females exhibited changes similar to those of males for five of the foraging variables. This parallel shift suggests a strong behavioral response by both sexes to proximate factors (such as vegetation structure, and prey abundance and distribution) that varied throughout the breeding season. Sex-specific foraging behavior during the prenestling period was best explained by differences in reproductive responsibilities rather than by the theory of intersexual competition for limited resources. During the nestling period, neither hypothesis by itself explained foraging divergences adequately. However, when integrated with the temporal responses of the warblers to changes in prey availability, reproductive responsibilities seemed to be of primary importance in explaining intersexual niche partitioning during the nestling period. We emphasize the importance of considering both intersexual and intraseasonal variation when quantifying a species' foraging ecology.
Comparing the role of fuel breaks across southern California national forests
Syphard, Alexandra D.; Keeley, Jon E.; Brennan, Teresa J.
2011-01-01
Fuel treatment of wildland vegetation is the primary approach advocated for mitigating fire risk at the wildland-urban interface (WUI), but little systematic research has been conducted to understand what role fuel treatments play in controlling large fires, which factors influence this role, or how the role of fuel treatments may vary over space and time. We assembled a spatial database of fuel breaks and fires from the last 30 years in four southern California national forests to better understand which factors are consistently important for fuel breaks in the control of large fires. We also explored which landscape features influence where fires and fuel breaks are most likely to intersect. The relative importance of significant factors explaining fuel break outcome and number of fire and fuel break intersections varied among the forests, which reflects high levels of regional landscape diversity. Nevertheless, several factors were consistently important across all the forests. In general, fuel breaks played an important role in controlling large fires only when they facilitated fire management, primarily by providing access for firefighting activities. Fire weather and fuel break maintenance were also consistently important. Models and maps predicting where fuel breaks and fires are most likely to intersect performed well in the regions where the models were developed, but these models did not extend well to other regions, reflecting how the environmental controls of fire regimes vary even within a single ecoregion. Nevertheless, similar mapping methods could be adopted in different landscapes to help with strategic location of fuel breaks. Strategic location of fuel breaks should also account for access points near communities, where fire protection is most important.
Kin Connection: Kin Involvement While Growing Up and Marriage in Adulthood
Raley, R. Kelly; Stokes, Charles E.
2010-01-01
Although previous research demonstrates the importance of the availability of marriageable men, earnings, and employment stability for racial differences in marriage, it also suggests that other factors likely contribute to this variation. This study investigates a new factor that might help to explain racial variation in marriage, the kinship group. To explore this possible connection, we examine the influence of parental kin involvement experienced during childhood and adolescence on marriage in adulthood using all three waves of the National Survey of Families and Households. While few of the measures of kin ties have significant effects on marriage, some measures were significantly related and the patterns of associations sometimes varied by race. PMID:21383868
EDUCATIONAL DIFFERENTIALS IN U.S. ADULT MORTALITY: AN EXAMINATION OF MEDIATING FACTORS
Rogers, Richard G.; Hummer, Robert A.; Everett, Bethany G.
2016-01-01
We use human capital theory to develop hypotheses regarding the extent to which the association between educational attainment and U.S. adult mortality is mediated by such economic and social resources as family income and social support; such health behaviors as inactivity, smoking, and excessive drinking; and such physiological measures as obesity, inflammation, and cardiovascular risk factors. We employ the NHANES Linked Mortality File, a large nationally representative prospective data set that includes an extensive number of factors thought to be important in mediating the education-mortality association. We find that educational differences in mortality for the total population and for specific causes of death are most prominently explained by family income and health behaviors. However, there are age-related differences in the effects of the mediating factors. Higher education enables individuals to effectively coalesce and leverage their diverse and substantial resources to reduce their mortality and increase their longevity. PMID:23347488
Factors Associated With American Indian and White Adolescent Drug Selling in Rural Communities
Eitle, David; Eitle, Tamela McNulty
2014-01-01
Relatively few studies have examined the correlates of adolescent drug selling in America, with most of these studies focusing on urban settings. The present study examines the risk and protective factors associated with drug selling among American Indian and white adolescents residing in a rural Northwestern state in the United States. Using survey data collected in 2010-2012, we conduct logistic regression analyses exploring the correlates of drug selling (n=568). Generally, we found support for prior explanations of drug selling, but identified some important race-specific differences. Specifically, we found that stress exposure was a risk factor for American Indians, but not whites. Conversely, academic achievement served as a protective factor for white adolescents but not American Indians. Our findings suggest that the race gap in rural drug selling can be explained by considering differences in social bonds, stress exposure, and exposure to substance using family and friends. PMID:26120365
The genetic epidemiology of personality disorders
Reichborn-Kjennerud, Ted
2010-01-01
Genetic epidemiologic studies indicate that all ten personality disorders (PDs) classified on the DSM-IV axis II are modestly to moderately heritable. Shared environmental and nonadditive genetic factors are of minor or no importance. No sex differences have been identified. Multivariate studies suggest that the extensive comorbidity between the PDs can be explained by three common genetic and environmental risk factors. The genetic factors do not reflect the DSM-IV cluster structure, but rather: i) broad vulnerability to PD pathology or negative emotionality; ii) high impulsivity/low agreeableness; and iii) introversion. Common genetic and environmental liability factors contribute to comorbidity between pairs or clusters of axis I and axis II disorders. Molecular genetic studies of PDs, mostly candidate gene association studies, indicate that genes linked to neurotransmitter pathways, especially in the serotonergic and dopaminergic systems, are involved. Future studies, using newer methods like genome-wide association, might take advantage of the use of endophenotypes. PMID:20373672
Thompson, Randall C; Allam, Adel H; Zink, Albert; Wann, L Samuel; Lombardi, Guido P; Cox, Samantha L; Frohlich, Bruno; Sutherland, M Linda; Sutherland, James D; Frohlich, Thomas C; King, Samantha I; Miyamoto, Michael I; Monge, Janet M; Valladolid, Clide M; El-Halim Nur El-Din, Abd; Narula, Jagat; Thompson, Adam M; Finch, Caleb E; Thomas, Gregory S
2014-06-01
Although atherosclerosis is widely thought to be a disease of modernity, computed tomographic evidence of atherosclerosis has been found in the bodies of a large number of mummies. This article reviews the findings of atherosclerotic calcifications in the remains of ancient people-humans who lived across a very wide span of human history and over most of the inhabited globe. These people had a wide range of diets and lifestyles and traditional modern risk factors do not thoroughly explain the presence and easy detectability of this disease. Nontraditional risk factors such as the inhalation of cooking fire smoke and chronic infection or inflammation might have been important atherogenic factors in ancient times. Study of the genetic and environmental risk factors for atherosclerosis in ancient people may offer insights into this common modern disease. Copyright © 2014 World Heart Federation (Geneva). Published by Elsevier B.V. All rights reserved.
Infectious and dietary risk factors of oral cancer.
Meurman, Jukka H
2010-06-01
In addition to the classic risk factors of oral cancer, namely alcohol and tobacco, other factors both infectious and environmental are thought to be associated with the development of oral malignancy. Infections in the oral cavity may be an important preventable cause of cancer. Poor oral hygiene, periodontal disease, chronic candidiasis, human papilloma virus (HPV) and herpesvirus infections link statistically with cancer but the mechanisms involved are largely unknown. Infections may trigger cell proliferation, inhibit apoptosis, interfere with cellular signaling mechanisms and up-regulate tumor promoters. In addition, several oral micro-organisms metabolize alcohol to carcinogenic acetaldehyde thus explaining the association between poor oral hygiene, alcohol consumption and carcinogenesis. With regards to dietary factors the Mediterranean-type fruit and vegetable rich diet has been shown to reduce the risk of oral cancer but the evidence is weak, the effect of individual food components and trace elements on carcinogenesis remains unclear at present. Copyright 2010 Elsevier Ltd. All rights reserved.
Bressan, Josefina; Hermsdorff, Helen H M; Zulet, María Angeles; Martínez, José Alfredo
2009-07-01
Healthy dietary pattern, characterized by the consumption of fruits, vegetables, white meats, skim dairy products, nuts and moderate intake of vegetable oils and alcohol, is an important factor for a lower risk of chronic disease such as obesity, metabolic syndrome and cardiovascular disease. This beneficial effect can be explained, at least partially, by its modulating role on biomarkers of insulin sensitivity and atherosclerosis as well as of inflammation and endothelial function. On the other hand, the intake of specific dietary factors, such as unsaturated fatty acids (oleic and alpha-linolenic) and micronutrients with antioxidant properties (vitamins A, E and C; selenium, zinc) has been discussed, due to its potential protector action due to chronic disease occurrence and its possible profits in hormonal, metabolic and inflammatory regulations that these dietetic factors can provide within a nutritional treatment to obesity and metabolic syndrome.