Molecular dynamics study of the conformational properties of cyclohexadecane

NASA Astrophysics Data System (ADS)

Zhang, Renshi; Mattice, Wayne L.

1993-06-01

Molecular dynamics has been used for the first time for the study of the conformational properties of cyclohexadecane, c-C16H32. By analyzing a long molecular dynamics trajectory (14.5 ns) at 450 K, equilibrium statistics such as the relative populations of different isomeric conformers and the probability ratios, p(gt)/p(tt), p(gg)/p(tt), and p(gg)/p(gtg), of different conformational segments, have been studied. The dynamic properties including the transition modes of gauche migration and gauche-pair creation, which have been reported before in n-alkanes, and the auto- and cross-correlations of the bond dihedral angles, have also been obtained. It was possible to make direct comparisons on some of the statistics with theory and experiment. Most of the results extracted from the molecular dynamics trajectory lie in between previously reported experimental and theoretical values. Many previously predicted conformers have been confirmed by our simulations. The results of the population probability of the most populated conformer seems to suggest that an earlier discrepancy between the theoretical works and an experimental work originates from insufficient samplings in earlier theoretical works, rather than from their inaccurate force field.

Collembola population levels 7 years after installation of the North Carolina long term soil productivity study

Treesearch

Robert J. Eaton

2006-01-01

Collembola are among the most abundant microarthropods in terrestrial ecosystems and have been shown to affect litter decomposition and nutrient release rates. Previous work 0-n the Croatan National Forest Long Term Soil Productivity (LTSP) study indicated organic matter removal and vegetation control treatments affected collembolan populations. The present study...

[Prevalence of the use of hypnotics and sedatives among the working population and associated work-related stress factors].

PubMed

Colell, Esther; Sánchez-Niubò, Albert; Domingo-Salvany, Antònia; Delclós, Jordi; Benavides, Fernando G

2014-01-01

To explore the prevalence of the use of hypnotics and sedatives in a sample of the Spanish working population and to examine its association with certain work-related stress factors. Using data from the 2007 Spanish Household Survey on Alcohol and Drugs (Encuesta Domiciliaria sobre Alcohol y Drogas en España [EDADES]), we analyzed the distribution of the use of hypnotics and sedatives in the previous month in the working population aged 16 to 64 years old (n=13,005). Associations with exposure to certain work-related stress factors (noxious working environment, precariousness, workload, and social support) were examined using logistic regression modelling. The prevalence of the use of hypnotics and sedatives among women in the previous month doubled that of men (6.5% and 3.3%, respectively), while use among the oldest age group was twice that of the youngest group in both sexes (10.2% in women and 5.5% in men older than 45 years), and was four times higher among those reporting poor health (18.9% in women and 11% in men). Concerning work-related stress, exposure to moderate (OR: 1.96; 95%CI: 1.31-2.92) and high (OR: 1.95; 95%CI: 1.14-3.34) levels of precariousness in men and moderate levels in women (OR: 1.43; 95%CI: 1.03-1.99) was associated with the use of hypnotics and sedatives. The prevalence of the use of hypnotics and sedatives was high in women and in workers older than 45 years. Further research is needed on the relationship between the use of hypnotics and sedatives and workers' health, and on the role that work-related stress factors play in this association. Copyright © 2014 SESPAS. Published by Elsevier Espana. All rights reserved.

Detecting population–environmental interactions with mismatched time series data

PubMed Central

Ferguson, Jake M.; Reichert, Brian E.; Fletcher, Robert J.; Jager, Henriëtte I.

2017-01-01

Time series analysis is an essential method for decomposing the influences of density and exogenous factors such as weather and climate on population regulation. However, there has been little work focused on understanding how well commonly collected data can reconstruct the effects of environmental factors on population dynamics. We show that, analogous to similar scale issues in spatial data analysis, coarsely sampled temporal data can fail to detect covariate effects when interactions occur on timescales that are fast relative to the survey period. We propose a method for modeling mismatched time series data that couples high-resolution environmental data to low-resolution abundance data. We illustrate our approach with simulations and by applying it to Florida’s southern Snail kite population. Our simulation results show that our method can reliably detect linear environmental effects and that detecting nonlinear effects requires high-resolution covariate data even when the population turnover rate is slow. In the Snail kite analysis, our approach performed among the best in a suite of previously used environmental covariates explaining Snail kite dynamics and was able to detect a potential phenological shift in the environmental dependence of Snail kites. Our work provides a statistical framework for reliably detecting population–environment interactions from coarsely surveyed time series. An important implication of this work is that the low predictability of animal population growth by weather variables found in previous studies may be due, in part, to how these data are utilized as covariates. PMID:28759123

Evaluation of the genetic distinctiveness of Greater Sage-grouse in the Bi-State Planning Area

USGS Publications Warehouse

Oyler-McCance, Sara J.; Casazza, Michael L.

2011-01-01

The purpose of this study was to further characterize a distinct population of Greater Sage-grouse: the population located along the border between Nevada and California (Bi-State Planning Area) and centered around the Mono Basin. This population was previously determined to be genetically distinct from other Greater Sage-grouse populations across their range. Previous genetic work focused on characterizing genetic variation across the species' range and thereby used a coarse sampling approach for species characterization. The goal of this study was to investigate this population further by obtaining samples from breeding locations within the population and analyzing those samples with the same mitochondrial and microsatellite loci used in previous studies. Blood samples were collected in six locations within the Bi-State Planning Area. Genetic data from subpopulations were then compared with each other and also with two populations outside of the Bi-State Planning Area. Particular attention was paid to subpopulation boundaries and internal dynamics by drawing comparisons among particular regions within the Bi-State Planning Area and regions proximal to it. All newly sampled subpopulations contained mitochondrial haplotypes and allele frequencies that were consistent with the genetically unique Bi-State (Mono Basin) Greater Sage-grouse described previously. This reinforces the fact that this group of Greater Sage-grouse is genetically unique and warrants special attention. Maintaining the genetic integrity of this population could protect the evolutionary potential of this population of Greater Sage-grouse. Additionally, the White Mountains subpopulation was found to be significantly distinct from all other Bi-State subpopulations.

Encouraging Survey Participation among Individuals Seeking HIV Prevention Services: Does a Community Identity Match Help or Hurt?

ERIC Educational Resources Information Center

Crowley, Jocelyn Elise; Roff, Brian H.; Lynch, Jeneve

2007-01-01

Understanding the behaviors and attitudes of at-risk populations is fundamental to controlling the spread of HIV, the virus that causes AIDS. The problem of nonresponse among these populations, however, plagues survey research designed to address these issues. Previous work undertaken to map out the dynamics of nonresponse--both noncontacts and…

What works best for whom? An exploratory, subgroup analysis in a randomized, controlled trial on the effectiveness of a workplace intervention in low back pain patients on return to work.

PubMed

Steenstra, Ivan A; Knol, Dirk L; Bongers, Paulien M; Anema, Johannes R; van Mechelen, Willem; de Vet, Henrica C W

2009-05-20

Exploratory subgroup analysis in a randomized controlled trial (RCT). To detect possible moderators in the effectiveness of a workplace intervention in a population of workers with sick leave due to sub acute nonspecific low back pain. In a recently published RCT, a workplace intervention was effective on return to work, compared to usual care. Examining the heterogeneity of effect sizes within the population in this RCT (n = 196) can lead to information on the effectiveness of the intervention in subgroups of patients. A subgroup analysis was performed by adding interaction terms to the statistical model. Before analysis the following possible moderators for treatment were identified: age, gender, pain, functional status, heavy work, and sick leave in the previous 12 months. Cox regression analyses were performed and survival curves were plotted. The interaction (P = 0.02) between age (dichotomized at the median value) and the workplace intervention indicates a modifying effect. The workplace intervention is more effective for workers > or =44 years (HR, 95% CI = 2.5, [1.6, 4.1] vs. 1.2 [0.8, 1.8] for workers <44 years old). The interaction between sick leave in the previous 12 months and the workplace intervention is significant (P = 0.02). The intervention is more effective for workers with previous sick leave (HR, 95% CI = 2.8 [1.7, 4.9] vs. 1.3 [0.8, 2.0]). A modifying effect of gender, heavy work, and pain score and functional status on the effectiveness of this intervention was not found. The findings from these exploratory analyses should be tested in future RCTs. This workplace intervention seems very suitable for return to work of older workers and workers with previous sick leave. Gender, perceived heavy work, and baseline scores in pain and functional status should not be a basis for assignment to this intervention.

Anxiety Profiles in Children with and without Developmental Coordination Disorder

ERIC Educational Resources Information Center

Pratt, Michelle L.; Hill, Elisabeth L.

2011-01-01

Previous work has highlighted that children diagnosed with DCD may be at risk of greater problems related to emotional wellbeing. However, to date much work has relied on population based samples, and anxiety has not been examined within a group of children given a clinical diagnosis of DCD. Additionally, the profile of individual differences has…

Immigrant workers in the United States: recent trends, vulnerable populations, and challenges for occupational health.

PubMed

McCauley, Linda A

2005-07-01

Immigrant workers are a rapidly growing segment of the U.S. work force, and these increasing numbers have resulted in a different ethnic mix in the work force than in previous decades. Immigrant workers are not a homogenous group, but are over-represented in low-paying occupations. Their diversity and vulnerability present distinct challenges for occupational health nurses. High-risk occupations in which a large proportion of immigrant workers are hired include agriculture, sweatshops, day laborers, and construction. Initiatives needed to improve the working conditions of this vulnerable population include improved surveillance and research, culturally competent care providers, improved health care access, advocacy, and changes in immigration and health policy.

Polymorphism at the ref(2)P locus in Drosophila melanogaster: preliminary experiments concerning the selection mechanisms involved in its maintenance.

PubMed

Fleuriet, A

1981-02-01

It has been shown previously that a polymorphism for two alleles of the ref(2)P locus is a regular feature of French natural populations of Drosophila melanogaster and that this is maintained in laboratory populations raised in cages. In this paper, an experimental population and egg-collection experiments are reported. Differential survival of the three genotypes would be the main factor leading to the equilibrium frequencies, working only in drastic conditions of larval competition.

Work organization, exposure to workplace hazards and sickness presenteeism in the European employed population.

PubMed

d'Errico, Angelo; Ardito, Chiara; Leombruni, Roberto

2016-01-01

Aim of the study was to identify work organization features and workplace hazards associated with sickness presenteeism (SP) among European workers. The study was conducted on data from the European Working Conditions Survey 2010 and included a study population of 30,279 employees. The relationship between work-related factors and SP was assessed through Poisson multivariate robust regression models, adjusting for significant (P < 0.05) individual and work-related characteristics. SP for at least 2 days in the previous year was reported by 35% of the workers. In fully adjusted model, several psychosocial (decision authority, skill discretion, reward, abuse; psychological, cognitive, and emotional demand), and organizational factors (shift work, working with clients, long work hours) were positively associated with SP, whereas job insecurity and exposure to physical factors (lifting or moving people, vibration) decreased SP risk. Our results support the importance of work-related factors, especially psychosocial exposures and organizational features, in determining workers' SP. © 2015 Wiley Periodicals, Inc.

An agent-based computational model for tuberculosis spreading on age-structured populations

NASA Astrophysics Data System (ADS)

Graciani Rodrigues, C. C.; Espíndola, Aquino L.; Penna, T. J. P.

2015-06-01

In this work we present an agent-based computational model to study the spreading of the tuberculosis (TB) disease on age-structured populations. The model proposed is a merge of two previous models: an agent-based computational model for the spreading of tuberculosis and a bit-string model for biological aging. The combination of TB with the population aging, reproduces the coexistence of health states, as seen in real populations. In addition, the universal exponential behavior of mortalities curves is still preserved. Finally, the population distribution as function of age shows the prevalence of TB mostly in elders, for high efficacy treatments.

Proportion of Dermatitis Attributed to Work Exposures in the Working Population, United States, 2011 Behavioral Risk Factor Surveillance System

PubMed Central

Ehrlich, Emily; Bunn, Terry; Kanotra, Sarojini; Fussman, Chris; Rosenman, Kenneth D.

2016-01-01

Background The US employer-based surveillance system for work-related health conditions underestimates the prevalence of work-related dermatitis. Objective The authors sought to utilize information from workers to improve the accuracy of prevalence estimates for work-related dermatitis. Methods Three state health departments included questions in the 2011 Behavioral Risk Factor Surveillance System survey designed to ascertain the prevalence of dermatitis in the working population, as well as healthcare experiences, personal perceptions of work-relatedness, and job changes associated with dermatitis. Results The percentage of working respondents who reported receiving a clinician’s opinion that their dermatitis was work-related was between 3.8% and 10.2%. When patients’ perceptions were considered, the work-related dermatitis prevalence estimate increased to between 12.9% and 17.6%. Conclusions Including patients’ perceptions of work-relatedness produced a larger prevalence estimate for work-related dermatitis than the previously published estimate of 5.6%, which included only those cases of dermatitis attributed to work by healthcare professionals. PMID:24619601

Evolution of cooperation in a finite homogeneous graph.

PubMed

Taylor, Peter D; Day, Troy; Wild, Geoff

2007-05-24

Recent theoretical studies of selection in finite structured populations have worked with one of two measures of selective advantage of an allele: fixation probability and inclusive fitness. Each approach has its own analytical strengths, but given certain assumptions they provide equivalent results. In most instances the structure of the population can be specified by a network of nodes connected by edges (that is, a graph), and much of the work here has focused on a continuous-time model of evolution, first described by ref. 11. Working in this context, we provide an inclusive fitness analysis to derive a surprisingly simple analytical condition for the selective advantage of a cooperative allele in any graph for which the structure satisfies a general symmetry condition ('bi-transitivity'). Our results hold for a broad class of population structures, including most of those analysed previously, as well as some for which a direct calculation of fixation probability has appeared intractable. Notably, under some forms of population regulation, the ability of a cooperative allele to invade is seen to be independent of the nature of population structure (and in particular of how game partnerships are specified) and is identical to that for an unstructured population. For other types of population regulation our results reveal that cooperation can invade if players choose partners along relatively 'high-weight' edges.

How Life History Can Sway the Fixation Probability of Mutants

PubMed Central

Li, Xiang-Yi; Kurokawa, Shun; Giaimo, Stefano; Traulsen, Arne

2016-01-01

In this work, we study the effects of demographic structure on evolutionary dynamics when selection acts on reproduction, survival, or both. In contrast to the previously discovered pattern that the fixation probability of a neutral mutant decreases while the population becomes younger, we show that a mutant with a constant selective advantage may have a maximum or a minimum of the fixation probability in populations with an intermediate fraction of young individuals. This highlights the importance of life history and demographic structure in studying evolutionary dynamics. We also illustrate the fundamental differences between selection on reproduction and selection on survival when age structure is present. In addition, we evaluate the relative importance of size and structure of the population in determining the fixation probability of the mutant. Our work lays the foundation for also studying density- and frequency-dependent effects in populations when demographic structures cannot be neglected. PMID:27129737

Polymorphism at the REF(2)P Locus in DROSOPHILA MELANOGASTER: Preliminary Experiments concerning the Selection Mechanisms Involved in Its Maintenance

PubMed Central

Fleuriet, Annie

1981-01-01

It has been shown previously that a polymorphism for two alleles of the ref(2)P locus is a regular feature of French natural populations of Drosophila melanogaster and that this is maintained in laboratory populations raised in cages. In this paper, an experimental population and egg-collection experiments are reported. Differential survival of the three genotypes would be the main factor leading to the equilibrium frequencies, working only in drastic conditions of larval competition. PMID:6791986

Genetic differences among Haplorchis taichui populations in Indochina revealed by mitochondrial COX1 sequences.

PubMed

Thaenkham, U; Phuphisut, O; Nuamtanong, S; Yoonuan, T; Sa-Nguankiat, S; Vonghachack, Y; Belizario, V Y; Dung, D T; Dekumyoy, P; Waikagul, J

2017-09-01

Haplorchis taichui is an intestinal heterophyid fluke that is pathogenic to humans. It is widely distributed in Asia, with a particularly high prevalence in Indochina. Previous work revealed that the lack of gene flow between three distinct populations of Vietnamese H. taichui can be attributed to their geographic isolation with no interconnected river basins. To test the hypothesis that interconnected river basins allow gene flow between otherwise isolated populations of H. taichui, as previously demonstrated for another trematode, Opisthorchis viverrini, we compared the genetic structures of seven populations of H. taichui from various localities in the lower Mekong Basin, in Thailand and Laos, with those in Vietnam, using the mitochondrial cytochrome c oxidase subunit 1 (COX1) gene. To determine the gene flow between these H. taichui populations, we calculated their phylogenetic relationships, genetic distances and haplotype diversity. Each population showed very low nucleotide diversity at this locus. However, high levels of genetic differentiation between the populations indicated very little gene flow. A phylogenetic analysis divided the populations into four clusters that correlated with the country of origin. The negligible gene flow between the Thai and Laos populations, despite sharing the Mekong Basin, caused us to reject our hypothesis. Our data suggest that the distribution of H. taichui populations was incidentally associated with national borders.

Genome-wide association study of ancestry-specific TB risk in the South African Coloured population

PubMed Central

Chimusa, Emile R.; Zaitlen, Noah; Daya, Michelle; Möller, Marlo; van Helden, Paul D.; Mulder, Nicola J.; Price, Alkes L.; Hoal, Eileen G.

2014-01-01

The worldwide burden of tuberculosis (TB) remains an enormous problem, and is particularly severe in the admixed South African Coloured (SAC) population residing in the Western Cape. Despite evidence from twin studies suggesting a strong genetic component to TB resistance, only a few loci have been identified to date. In this work, we conduct a genome-wide association study (GWAS), meta-analysis and trans-ethnic fine mapping to attempt the replication of previously identified TB susceptibility loci. Our GWAS results confirm the WT1 chr11 susceptibility locus (rs2057178: odds ratio = 0.62, P = 2.71e−06) previously identified by Thye et al., but fail to replicate previously identified polymorphisms in the TLR8 gene and locus 18q11.2. Our study demonstrates that the genetic contribution to TB risk varies between continental populations, and illustrates the value of including admixed populations in studies of TB risk and other complex phenotypes. Our evaluation of local ancestry based on the real and simulated data demonstrates that case-only admixture mapping is currently impractical in multi-way admixed populations, such as the SAC, due to spurious deviations in average local ancestry generated by current local ancestry inference methods. This study provides insights into identifying disease genes and ancestry-specific disease risk in multi-way admixed populations. PMID:24057671

Methods to recognize work-related cancer in workplaces, the general population, and by experts in the clinic, a Norwegian experience

PubMed Central

2011-01-01

Background In most countries, the numbers of work-related cancer identified are much lower than are the estimated total burden of cancer caused by exposure at work. Therefore, there is a great need to use all available practical as well as epidemiological methods for identification as well as to develop new methods of recognizing cases of work-related cancers. Methods Primarily based on practical experiences from Norway, methods to identify cases of possible work-related cancers in the general population and at workplaces as well as methods to recognize more specific cases after referral to specialized clinics are reviewed in this publication. Results Countries applying a number of the available methods to detect work-related cancer reach a reporting rate of 60 such cases per million, while other countries that do not employ such methods hardly identify any cases. As most subjects previously exposed to cancer causing agents and substances at work are gradually recruited out of work, methods should be versatile for identification of cases in the general population, as well as at work. Conclusions Even in countries using a number of the available methods for identification, only a limited fraction of the real number of work-related cancer are notified to the labour inspectorate. Clinicians should be familiar with the methods and do the best to identify work-related cancer to serve prevention. PMID:21899752

Asthma caused by occupational exposures is common – A systematic analysis of estimates of the population-attributable fraction

PubMed Central

Torén, Kjell; Blanc, Paul D

2009-01-01

Background The aim of this paper is to highlight emerging data on occupational attributable risk in asthma. Despite well documented outbreaks of disease and the recognition of numerous specific causal agents, occupational exposures previously had been relegated a fairly minor role relative to other causes of adult onset asthma. In recent years there has been a growing recognition of the potential importance of asthma induced by work-related exposures Methods We searched Pub Med from June 1999 through December 2007. We identified six longitudinal general population-based studies; three case-control studies and eight cross-sectional analyses from seven general population-based samples. For an integrated analysis we added ten estimates prior to 1999 included in a previous review. Results The longitudinal studies indicate that 16.3% of all adult-onset asthma is caused by occupational exposures. In an overall synthesis of all included studies the overall median PAR value was 17.6%. Conclusion Clinicians should consider the occupational history when evaluating patients in working age who have asthma. At a societal level, these findings underscore the need for further preventive action to reduce the occupational exposures to asthma-causing agents. PMID:19178702

Hiring appropriate providers for different populations: acute care nurse practitioners.

PubMed

Haut, Cathy; Madden, Maureen

2015-06-01

Acute care nurse practitioners, prepared as providers for a variety of populations of patients, continue to make substantial contributions to health care. Evidence indicates shorter stays, higher satisfaction among patients, increased work efficiency, and higher quality outcomes when acute care nurse practitioners are part of unit- or service-based provider teams. The Consensus Model for APRN Regulation: Licensure, Accreditation, Certification, and Education outlines detailed guidelines for matching nurse practitioners' education with certification and practice by using a population-focused algorithm. Despite national support for the model, nurse practitioners and employers continue to struggle with finding the right fit. Nurse practitioners often use their interest and previous nursing experience to apply for an available position, and hospitals may not understand preparation or regulations related to matching the appropriate provider to the work environment. Evidence and regulatory guidelines indicate appropriate providers for population-focused positions. This article presents history and recommendations for hiring acute care nurse practitioners as providers for different populations of patients. ©2015 American Association of Critical-Care Nurses.

Settling behavior of unpurified Cryptosporidium oocysts in laboratory settling columns.

PubMed

Young, Pamela L; Komisar, Simeon J

2005-04-15

The settling behavior of fresh and aged unpurified oocysts was examined in settling column suspensions with varied ionic strengths and concentrations of calcium and magnesium. Independent measurements of the size and density of unpurified oocysts were performed to determine a theoretical settling velocity for the test populations. Viability of the oocysts was assessed using a dye permeability assay. Latex microspheres were included to provide a standard by which to assess the settling conditions in the columns. Mean settling velocities for viable oocysts measured in this work were faster than predicted and faster than measured for purified oocysts in other work: 1.31 (+/-0.21) microm/s for viable oocysts from populations having a low percentage of viable oocysts and 1.05 (+/-0.20) microm/s for viable oocysts from populations with a high percentage of viable oocysts. Results were attributed to the higher than previously reported densities measured for oocysts in this study and the presence of fecal material, which allowed opportunity for particle agglomeration. Settling velocity of oocysts was significantly related to the viability of the population, particle concentration, ionic strength, and presence of calcium and magnesium in the suspending medium. Behavior of the latex microspheres was not entirely predictive of the behavior of the oocysts under the test conditions. Viable oocysts may have a greater probability of settling than previously assumed; however, nonviable, and especially nonintact, oocysts have the potential to be significantly transported in water. This work underscores the importance of assessing the viability of oocysts to predict their response to environmental and experimental conditions.

Thermal Timescale Mass Transfer In Binary Population Synthesis

NASA Astrophysics Data System (ADS)

Justham, S.; Kolb, U.

2004-07-01

Studies of binary evolution have, until recently, neglected thermal timescale mass transfer (TTMT). Recent work has suggested that this previously poorly studied area is crucial in the understanding of systems across the compact binary spectrum. We use the state-of-the-art binary population synthesis code BiSEPS (Willems and Kolb, 2002, MNRAS 337 1004-1016). However, the present treatment of TTMT is incomplete due to the nonlinear behaviour of stars in their departure from gravothermal `equilibrium'. Here we show work that should update the ultrafast stellar evolution algorithms within BiSEPS to make it the first pseudo-analytic code that can follow TTMT properly. We have generated fits to a set of over 300 Case B TTMT sequences with a range of intermediate-mass donors. These fits produce very good first approximations to both HR diagrams and mass-transfer rates (see figures 1 and 2), which we later hope to improve and extend. They are already a significant improvement over the previous fits.

Paid and unpaid work, and its relation to low back and neck/shoulder disorders among women.

PubMed

Josephson, Malin; Ahlberg, Gunnel; Härenstam, Annika; Svensson, Helena; Theorell, Töres; Wiktorin, Christina; Vingård, Eva

2003-01-01

The aim of the present study was to estimate the influence of total work hours, paid work in the labor market and unpaid work in the family domain, on care-seeking for low back and neck/shoulder disorders in the female population. The exposure assessments considered a typical working' day during the previous twelve months and were assessed by interviews and questionnaires; 704 cases and 984 referents were examined. The cases had sought professional care during the study period; the referents were randomly selected from the same source population. There was no increased relative risk for care-seeking for low back and neck/shoulder disorders for gainfully employed women compared to those not employed, or for full-time compared to part-time working women. At least 60 hours per week of paid work, or at least 40 hours per week of unpaid work, separately, indicated an increased relative risk for care-seeking. The present results did not strengthen the hypothesis that a high amount of hours of work is an independent risk factor for musculoskeletal disorders.

Burnout in the working population: relations to psychosocial work factors.

PubMed

Lindblom, Karin M; Linton, Steven J; Fedeli, Cecilia; Bryngelsson, Ing-Liss

2006-01-01

This study investigated levels of burnout in the general population irrespective of occupation and relations between burnout and psychosocial work factors. A cross-sectional survey featuring sleep problems, psychological distress, burnout (Maslach Burnout Inventory-General Survey), and psychosocial factors at work, was mailed to a random sample of 3,000 participants, aged 20-60. Response rate was 61%. A high level (18%), a low level (19%), and an intermediate group (63%) for burnout were constructed. The high level group was associated with those who were > 50 years old, women, those experiencing psychological distress, and those with a poor psychosocial work climate. The analyses on variables significant in previous analyses showed that the high level group was strongly related to high demands, low control, lack of social support, and disagreeing about values at the workplace even when accounting for age, gender, and psychological distress. We conclude that psychosocial work factors are important in association to burnout regardless of occupation.

Military duty: risk factor for preterm labor? A review.

PubMed

McNeary, A M; Lomenick, T S

2000-08-01

The female military population represents a high-risk group for preterm labor and other adverse pregnancy outcomes. As the number of women entering the armed forces continues to increase, concerns regarding the effects of military service on pregnancy must persist. Although active duty females have access to prenatal care and maintain consistent follow-up, previous research has noted a 5-fold increase in preterm labor compared with civilian working women. Hospitalization and loss of work attributable to pregnancy complications directly affect productivity and mission accomplishment; therefore, it is crucial to identify those at risk to institute measures that will prevent such occurrences and decrease time away from work. This article provides a review of the existing literature concerning preterm labor in military women, comparisons with the civilian population, and recommendations for future research.

Metapopulation models for historical inference.

PubMed

Wakeley, John

2004-04-01

The genealogical process for a sample from a metapopulation, in which local populations are connected by migration and can undergo extinction and subsequent recolonization, is shown to have a relatively simple structure in the limit as the number of populations in the metapopulation approaches infinity. The result, which is an approximation to the ancestral behaviour of samples from a metapopulation with a large number of populations, is the same as that previously described for other metapopulation models, namely that the genealogical process is closely related to Kingman's unstructured coalescent. The present work considers a more general class of models that includes two kinds of extinction and recolonization, and the possibility that gamete production precedes extinction. In addition, following other recent work, this result for a metapopulation divided into many populations is shown to hold both for finite population sizes and in the usual diffusion limit, which assumes that population sizes are large. Examples illustrate when the usual diffusion limit is appropriate and when it is not. Some shortcomings and extensions of the model are considered, and the relevance of such models to understanding human history is discussed.

Low-frequency Carbon Radio Recombination Lines. I. Calculations of Departure Coefficients

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

Salgado, F.; Morabito, L. K.; Oonk, J. B. R.

In the first paper of this series, we study the level population problem of recombining carbon ions. We focus our study on high quantum numbers, anticipating observations of carbon radio recombination lines to be carried out by the Low Frequency Array. We solve the level population equation including angular momentum levels with updated collision rates up to high principal quantum numbers. We derive departure coefficients by solving the level population equation in the hydrogenic approximation and including low-temperature dielectronic capture effects. Our results in the hydrogenic approximation agree well with those of previous works. When comparing our results including dielectronicmore » capture, we find differences that we ascribe to updates in the atomic physics (e.g., collision rates) and to the approximate solution method of the statistical equilibrium equations adopted in previous studies. A comparison with observations is discussed in an accompanying article, as radiative transfer effects need to be considered.« less

Risk factors for first trimester miscarriage--results from a UK-population-based case-control study.

PubMed

Maconochie, N; Doyle, P; Prior, S; Simmons, R

2007-02-01

The aim of this study was to examine the association between biological, behavioural and lifestyle risk factors and risk of miscarriage. Population-based case-control study. Case-control study nested within a population-based, two-stage postal survey of reproductive histories of women randomly sampled from the UK electoral register. Six hundred and three women aged 18-55 years whose most recent pregnancy had ended in first trimester miscarriage (<13 weeks of gestation; cases) and 6116 women aged 18-55 years whose most recent pregnancy had progressed beyond 12 weeks (controls). Women were questioned about socio-demographic, behavioural and other factors in their most recent pregnancy. First trimester miscarriage. After adjustment for confounding, the following were independently associated with increased risk: high maternal age; previous miscarriage, termination and infertility; assisted conception; low pre-pregnancy body mass index; regular or high alcohol consumption; feeling stressed (including trend with number of stressful or traumatic events); high paternal age and changing partner. Previous live birth, nausea, vitamin supplementation and eating fresh fruits and vegetables daily were associated with reduced risk, as were feeling well enough to fly or to have sex. After adjustment for nausea, we did not confirm an association with caffeine consumption, smoking or moderate or occasional alcohol consumption; nor did we find an association with educational level, socio-economic circumstances or working during pregnancy. The results confirm that advice to encourage a healthy diet, reduce stress and promote emotional wellbeing might help women in early pregnancy (or planning a pregnancy) reduce their risk of miscarriage. Findings of increased risk associated with previous termination, stress, change of partner and low pre-pregnancy weight are noteworthy, and we recommend further work to confirm these findings in other study populations.

The United States Army in the Phillippine Insurrection, 1899-1902

DTIC Science & Technology

1975-06-06

authoritative previous works on the period. The United. States ultimately suppressed the Philippine Insurrec- tion by using many of the broad internial defense...application of rules for se~arating the population from the revolutionary movement. _However, language and cultural limitations, as well as the threat rjf...Congress; and in organiztional histories and biographical materialsl as well a& in a nimber of scholarly and authoritative works on the 3panish-American Wr

Work-related suicide in Victoria, Australia: a broad perspective.

PubMed

Routley, Virginia Hazel; Ozanne-Smith, Joan E

2012-01-01

While unintentional work-related injury is increasingly recognised as important and preventable, population studies of the full range of work related suicides have received less attention. The objective of this study is to investigate the epidemiology of work-related suicide in Victoria, July 2000-December 2007. The study draws on a database of all work-related deaths reported to the Victorian Coroner, inclusive of broadly defined work-relatedness. Inclusion criteria for work-related suicide were at least one of: suicide means was work related, work stressors were identified in police reports to the Coroners or the Coroner's finding, the suicide method involved another person's work (e.g. rail suicide, heavy vehicle) or the suicide location was a workplace. Cases still open for investigation were excluded. Of 642 work-related suicides, 55% had an association with work stressors; 32% jumped or lay in front of a train or heavy vehicle; 7% involved a work location and 6% involved work agents. Work stressor cases identified included business difficulties, recent or previous work injury, unemployment/redundancy or conflict with supervisors/colleagues (including workplace bullying). Work-related suicide is a substantial problem, for which few detailed population wide studies are available. Further research is required to understand the contribution of work stressors and effective interventions.

Behaviour State Analysis in Rett Syndrome: Continuous Data Reliability Measurement

ERIC Educational Resources Information Center

Woodyatt, Gail; Marinac, Julie; Darnell, Ross; Sigafoos, Jeff; Halle, James

2004-01-01

Awareness of optimal behaviour states of children with profound intellectual disability has been reported in the literature as a potentially useful tool for planning intervention within this population. Some arguments have been raised, however, which question the reliability and validity of previously published work on behaviour state analysis.…

Suicide Awareness and Prevention Workshop for Social Workers and Paraprofessionals

ERIC Educational Resources Information Center

Levitt, Aaron J.; Lorenzo, Julie; Yu, Van; Wean, Caren; Miller-Solarino, Sophie

2011-01-01

Social workers and paraprofessionals serve psychiatric populations at high risk for suicide, but may receive little training related to suicidality. This study evaluated a suicide awareness and prevention training workshop for providers working with mentally ill homeless and previously homeless adults. Trainees attended a half day of training, and…

Region, landscape, and host plant effects on reproduction by a mobile, multivoltine arthropod herbivore

USDA-ARS?s Scientific Manuscript database

Community structure, species abundance, and biotic interactions of invertebrate species in farmlands are influenced by larger-scale processes at region and landscape levels. While previous work makes clear the importance of landscape factors for natural enemy populations, relatively less is known ab...

Thermodynamics and Human Population

ERIC Educational Resources Information Center

Cordry, Sean M.

2010-01-01

This paper discusses a Fermi-problem exercise through which I take students in several of my college courses. Students work in teams, determining the average daily Caloric needs per person. Then they use insolation values to determine the size of a collection area needed to absorb the previously determined daily energy requirements. Adjustments to…

Risk of injury after evening and night work - findings from the Danish Working Hour Database.

PubMed

Nielsen, Helena B; Larsen, Ann D; Dyreborg, Johnny; Hansen, Åse M; Pompeii, Lisa A; Conway, Sadie H; Hansen, Johnni; Kolstad, Henrik A; Nabe-Nielsen, Kirsten; Garde, Anne H

2018-05-08

Objectives Evening and night work have been associated with higher risk of injury than day work. However, previous findings may be affected by recall bias and unmeasured confounding from differences between day, evening and night workers. This study investigates whether evening and night work during the past week increases risk of injury when reducing recall bias and unmeasured confounding. Methods We linked daily working hours at the individual level of 69 200 employees (167 726 person years from 2008-2015), primarily working at hospitals to registry information on 11 834 injuries leading to emergency room visits or death. Analyses were conducted with Poisson regression models in the full population including permanent day, evening and night workers, and in two sub-populations of evening and night workers, with both day and evening or night work, respectively. Thus, the exchangeability between exposure and reference group was improved in the two sub-populations. Results Risk of injury was higher after a week with evening work [incidence rate ratio (IRR) 1.32, 95% confidence interval (CI) 1.26-1.37] and night work (IRR 1.33, 95% CI 1.25-1.41) compared with only day work. Similar, although attenuated, estimates were found for evening work among evening workers (IRR 1.18, 95% CI 1.12-1.25), and for night work among night workers (IRR 1.10, 95% CI 1.01-1.20). Conclusion There is an overall increased risk of injury after a week that has included evening or night work compared with only day work. Though attenuated, the higher risk remains after reducing unmeasured confounding.

Population, Migration, and Arctic Community Change

NASA Astrophysics Data System (ADS)

Hamilton, L.; Wirsing, J.

2017-12-01

North American Arctic communities commonly show decadal trends in population growth, driven by natural increase but variably offset by net migration with year-to-year volatility. Migration rates themselves can be a social indicator, integrating a range of push and pull factors. Population and population change of Arctic communities are basic scale properties affecting the resources needed to achieve sustainability, and the adaptations that may be required for climate change (such as relocation from flood-threatened locations). We examine interannual changes 1990-2016 in population and net migration of 43 Alaska Arctic communities, some facing serious threats of flooding. Our Alaska analysis updates previous work with additional years of data. We also extend this demographic analysis for the first time to 25 towns and villages of Nunavut, Canada.

World Population Stabilization Unlikely This Century

PubMed Central

Gerland, Patrick; Raftery, Adrian E.; Ševcíková, Hana; Li, Nan; Gu, Danan; Spoorenberg, Thomas; Alkema, Leontine; Fosdick, Bailey K.; Chunn, Jennifer; Lalic, Nevena; Bay, Guiomar; Buettner, Thomas; Heilig, Gerhard K.; Wilmoth, John

2014-01-01

The United Nations recently released population projections based on data until 2012 and a Bayesian probabilistic methodology. Analysis of these data reveals that, contrary to previous literature, world population is unlikely to stop growing this century. There is an 80% probability that world population, now 7.2 billion, will increase to between 9.6 and 12.3 billion in 2100. This uncertainty is much smaller than the range from the traditional UN high and low variants. Much of the increase is expected to happen in Africa, in part due to higher fertility and a recent slowdown in the pace of fertility decline. Also, the ratio of working age people to older people is likely to decline substantially in all countries, even those that currently have young populations. PMID:25301627

Possible ancestral structure in human populations.

PubMed

Plagnol, Vincent; Wall, Jeffrey D

2006-07-01

Determining the evolutionary relationships between fossil hominid groups such as Neanderthals and modern humans has been a question of enduring interest in human evolutionary genetics. Here we present a new method for addressing whether archaic human groups contributed to the modern gene pool (called ancient admixture), using the patterns of variation in contemporary human populations. Our method improves on previous work by explicitly accounting for recent population history before performing the analyses. Using sequence data from the Environmental Genome Project, we find strong evidence for ancient admixture in both a European and a West African population (p approximately 10(-7)), with contributions to the modern gene pool of at least 5%. While Neanderthals form an obvious archaic source population candidate in Europe, there is not yet a clear source population candidate in West Africa.

Effects of population density on corticosterone levels of prairie voles in the field

PubMed Central

Blondel, Dimitri V.; Wallace, Gerard N.; Calderone, Stefanie; Gorinshteyn, Marija; St. Mary, Colette M.; Phelps, Steven M.

2015-01-01

High population density is often associated with increased levels of stress-related hormones, such as corticosterone (CORT). Prairie voles (Microtus ochrogaster) are a socially monogamous species known for their large population density fluctuations in the wild. Although CORT influences the social behavior of prairie voles in the lab, the effect of population density on CORT has not previously been quantified in this species in the field. We validated a non-invasive hormone assay for measuring CORT metabolites in prairie vole feces. We then used semi-natural enclosures to experimentally manipulate population density, and measured density effects on male space use and fecal CORT levels. Our enclosures generated patterns of space use and social interaction that were consistent with previous prairie vole field studies. Contrary to the positive relationship between CORT and density typical of other taxa, we found that lower population densities (80 animals/ha) produced higher fecal CORT than high densities (240/ha). Combined with prior work in the lab and field, the data suggest that high prairie vole population densities indicate favorable environments, perhaps through reduced predation risk. Lastly, we found that field animals had lower fecal CORT levels than laboratory-living animals. The data emphasize the usefulness of prairie voles as models for integrating ecological, evolutionary and mechanistic questions in social behavior. PMID:26342968

Pitfalls, Potentials, and Ethics of Online Survey Research: LGBTQ and Other Marginalized and Hard-to-Access Youths.

PubMed

McInroy, Lauren B

2016-06-01

Online research methodologies may serve as an important mechanism for population-focused data collection in social work research. Online surveys have become increasingly prevalent in research inquiries with young people and have been acknowledged for their potential in investigating understudied and marginalized populations and subpopulations, permitting increased access to communities that tend to be less visible-and thus often less studied-in offline contexts. Lesbian, gay, bisexual, transgender, and queer (LGBTQ) young people are a socially stigmatized, yet digitally active, youth population whose participation in online surveys has been previously addressed in the literature. Many of the opportunities and challenges of online survey research identified with LGBTQ youths may be highly relevant to other populations of marginalized and hard-to-access young people, who are likely present in significant numbers in the online environment (for example, ethnoracialized youths and low-income youths). In this article, the utility of online survey methods with marginalized young people is discussed, and recommendations for social work research are provided.

Do work-related factors contribute to differences in doctor-certified sick leave? A prospective study comparing women in health and social occupations with women in the general working population.

PubMed

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.

Neck Pain, Preoperative Opioids, and Functionality After Cervical Fusion.

PubMed

Faour, Mhamad; Anderson, Joshua T; Haas, Arnold R; Percy, Rick; Woods, Stephen T; Ahn, Uri M; Ahn, Nicholas U

2017-01-01

The use of opioids among patients with workers' compensation claims is associated with tremendous costs, especially for patients who undergo spinal surgery. This study compared return-to-work rates after single-level cervical fusion for degenerative disk disease between patients who received opioids before surgery and patients who underwent fusion with no previous opioid use. All study subjects qualified for workers' compensation benefits for injuries sustained at work between 1993 and 2011. The study population included 281 subjects who underwent single-level cervical fusion for degenerative disk disease with International Classification of Diseases, Ninth Revision, and Current Procedural Terminology code algorithms. The opioid group included 77 subjects who received opioids preoperatively. The control group included 204 subjects who had surgery with no previous opioid use. The primary outcome was meeting return-to-work criteria within 3 years of follow-up after fusion. Secondary outcome measures after surgery, surgical details, and presurgical characteristics for each cohort also were collected. In 36.4% of the opioid group, return-to-work criteria were met compared with 56.4% of the control group. Patients who took opioids were less likely to meet return-to-work criteria compared with the control group (odds ratio, 0.44; 95% confidence interval, 0.26-0.76; P=.0028). Return-to-work rates within the first year after fusion were 24.7% for the opioid group and 45.6% for the control group (P=.0014). Patients who used opioids were absent from work for 255 more days compared with the control group (P=.0001). The use of opioids for management of diskogenic neck pain, with the possibility of surgical intervention, is a negative predictor of successful return to work after fusion in a workers' compensation population. [Orthopedics. 2017; 40(1):25-32.]. Copyright 2016, SLACK Incorporated.

The non-equilibrium allele frequency spectrum in a Poisson random field framework.

PubMed

Kaj, Ingemar; Mugal, Carina F

2016-10-01

In population genetic studies, the allele frequency spectrum (AFS) efficiently summarizes genome-wide polymorphism data and shapes a variety of allele frequency-based summary statistics. While existing theory typically features equilibrium conditions, emerging methodology requires an analytical understanding of the build-up of the allele frequencies over time. In this work, we use the framework of Poisson random fields to derive new representations of the non-equilibrium AFS for the case of a Wright-Fisher population model with selection. In our approach, the AFS is a scaling-limit of the expectation of a Poisson stochastic integral and the representation of the non-equilibrium AFS arises in terms of a fixation time probability distribution. The known duality between the Wright-Fisher diffusion process and a birth and death process generalizing Kingman's coalescent yields an additional representation. The results carry over to the setting of a random sample drawn from the population and provide the non-equilibrium behavior of sample statistics. Our findings are consistent with and extend a previous approach where the non-equilibrium AFS solves a partial differential forward equation with a non-traditional boundary condition. Moreover, we provide a bridge to previous coalescent-based work, and hence tie several frameworks together. Since frequency-based summary statistics are widely used in population genetics, for example, to identify candidate loci of adaptive evolution, to infer the demographic history of a population, or to improve our understanding of the underlying mechanics of speciation events, the presented results are potentially useful for a broad range of topics. Copyright © 2016 Elsevier Inc. All rights reserved.

Efficient reinforcement learning of a reservoir network model of parametric working memory achieved with a cluster population winner-take-all readout mechanism.

PubMed

Cheng, Zhenbo; Deng, Zhidong; Hu, Xiaolin; Zhang, Bo; Yang, Tianming

2015-12-01

The brain often has to make decisions based on information stored in working memory, but the neural circuitry underlying working memory is not fully understood. Many theoretical efforts have been focused on modeling the persistent delay period activity in the prefrontal areas that is believed to represent working memory. Recent experiments reveal that the delay period activity in the prefrontal cortex is neither static nor homogeneous as previously assumed. Models based on reservoir networks have been proposed to model such a dynamical activity pattern. The connections between neurons within a reservoir are random and do not require explicit tuning. Information storage does not depend on the stable states of the network. However, it is not clear how the encoded information can be retrieved for decision making with a biologically realistic algorithm. We therefore built a reservoir-based neural network to model the neuronal responses of the prefrontal cortex in a somatosensory delayed discrimination task. We first illustrate that the neurons in the reservoir exhibit a heterogeneous and dynamical delay period activity observed in previous experiments. Then we show that a cluster population circuit decodes the information from the reservoir with a winner-take-all mechanism and contributes to the decision making. Finally, we show that the model achieves a good performance rapidly by shaping only the readout with reinforcement learning. Our model reproduces important features of previous behavior and neurophysiology data. We illustrate for the first time how task-specific information stored in a reservoir network can be retrieved with a biologically plausible reinforcement learning training scheme. Copyright © 2015 the American Physiological Society.

Sickness benefit claims due to mental disorders in Brazil: associations in a population-based study.

PubMed

Barbosa-Branco, Anadergh; Bültmann, Ute; Steenstra, Ivan

2012-10-01

This study aims to determine the prevalence and duration of sickness benefit claims due to mental disorders and their association with economic activity, sex, age, work-relatedness and income replacement using a population-based study of sickness benefit claims (> 15 days) due to mental disorders in Brazil carried out in 2008. The prevalence of mental disorders was 45.1 claims per 10,000 workers. Prevalence and duration of sickness benefit claims due to mental disorder were higher and longer in workers aged over 40 years. Prevalence of claims was 73% higher in women but duration of sickness benefit claims was longer in men. Prevalence rates for claims differed widely according to economic activity, with sewage, residential care and programming and broadcasting activities showing the highest rates. Claims were deemed to be work-related in 8.5% of cases with mental disorder showing low work-relatedness in Brazil. A wide variation of prevalence and duration between age, economic activity and work-relatedness was observed, suggesting that working conditions are a more important factor in mental disorder work disability than previously assumed.

Social Work Education: Achieving Transformative Learning through a Cultural Competence Model for Transformative Education

ERIC Educational Resources Information Center

Blunt, Kesha

2007-01-01

Migration across national borders has resulted in demographic changes in the United States, causing the country to become more multi-ethnic. This presents considerable challenges for graduate level educators who need to be responsive to the unique academic needs of diverse populations by considering students' previous experiences, values, and…

Comparison of Estimates in the 1996 National Household Education Survey. Working Paper Series.

ERIC Educational Resources Information Center

Nolin, Mary Jo; Collins, Mary A.; Vaden-Kiernan, Nancy; Davies, Elizabeth

This report compares selected estimates from the 1996 National Household Education Survey (NHES:96) with estimates from previous NHES collections, the Current Population Survey (CPS), and other relevant data sources. The comparisons provide an indication of the reasonableness of selected NHES:96 estimates. Where discrepancies were found between…

College Men's Intimate Partner Violence Attitudes: Contributions of Adult Attachment and Gender Role Stress

ERIC Educational Resources Information Center

Mcdermott, Ryon C.; Lopez, Frederick G.

2013-01-01

Primary prevention of men's intimate partner violence (IPV) toward women in dating relationships is an important area of psychological inquiry and a significant concern for counselors working with college student populations. Previous research has identified that certain beliefs condoning or accepting physical, sexual, and psychological violence…

Synthesizing Information from Language Samples and Standardized Tests in School-Age Bilingual Assessment

ERIC Educational Resources Information Center

Ebert, Kerry Danahy; Pham, Giang

2017-01-01

Purpose: Although language samples and standardized tests are regularly used in assessment, few studies provide clinical guidance on how to synthesize information from these testing tools. This study extends previous work on the relations between tests and language samples to a new population--school-age bilingual speakers with primary language…

Local interactions lead to pathogen-driven change to host population dynamics.

PubMed

Boots, Michael; Childs, Dylan; Reuman, Daniel C; Mealor, Michael

2009-10-13

Individuals tend to interact more strongly with nearby individuals or within particular social groups. Recent theoretical advances have demonstrated that these within-population relationships can have fundamental implications for ecological and evolutionary dynamics. In particular, contact networks are crucial to the spread and evolution of disease. However, the theory remains largely untested experimentally. Here, we manipulate habitat viscosity and thereby the frequency of local interactions in an insect-pathogen model system in which the virus had previously been shown to have little effect on host population dynamics. At high viscosity, the pathogen caused the collapse of dominant and otherwise stable host generation cycles. Modeling shows that this collapse can be explained by an increase in the frequency of intracohort interactions relative to intercohort interactions, leading to more disease transmission. Our work emphasizes that spatial structure can subtly mediate intraspecific competition and the effects of natural enemies. A decrease in dispersal in a population may actually (sometimes rather counterintuitively) intensify the effects of parasites. Broadly, because anthropological and environmental change often cause changes in population mixing, our work highlights the potential for dramatic changes in the effects of parasites on host populations.

Effects of punishment in a mobile population playing the prisoner's dilemma game

NASA Astrophysics Data System (ADS)

Amor, Daniel R.; Fort, Joaquim

2011-12-01

We deal with a system of prisoner's dilemma players undergoing continuous motion in a two-dimensional plane. In contrast to previous work, we introduce altruistic punishment after the game. We find punishing only a few of the cooperator-defector interactions is enough to lead the system to a cooperative state in environments where otherwise defection would take over the population. This happens even with soft nonsocial punishment (where both cooperators and defectors punish other players, a behavior observed in many human populations). For high enough mobilities or temptations to defect, low rates of social punishment can no longer avoid the breakdown of cooperation.

Prevalence of impaired fasting glucose and type 1 and 2 diabetes mellitus in a large nationwide working population in Spain.

PubMed

Reviriego, Jesús; Vázquez, Luis Alberto; Goday, Albert; Cabrera, Martha; García-Margallo, María Teresa; Calvo, Eva

2016-04-01

To report the prevalence of impaired fasting glucose (IFG), undiagnosed and diagnosed diabetes, and their association to occupational categories in a representative sample of working population in Spain. A cross-sectional study of workers who attended routine medical check-ups from January 2007 to December 2007. A structured questionnaire was completed, and physical examinations and routine serum biochemical tests were performed. IFG was defined as fasting glucose levels ranging from 100 to 125 mg/dl with no diagnosis of T1DM or T2DM; T1DM was defined as previous diagnosis of T1DM; and T2DM as previous diagnosis of T2DM, treatment with oral antidiabetic drugs or insulin or fasting glucose levels ≥126 mg/dl, according to ADA criteria. Of the 371,997 participants (median age 35 [interquartile range 29-44] years), 72.4% were male. Raw prevalence rates (95% CI) of IFG, undiagnosed (UKDM), and previously known type 2 (KDM2) and type 1 (KDM1) diabetes were 10.4% (10.3-10.5%), 1.3% (1.2-1.3%), 1.1% (1.1-1.2%), and 0.3% (0.3-0.3%), respectively. With the exception of KDM1, prevalence of these conditions increased with age and was greater among manual/blue-collar workers (12.1%, 1.5%, 1.3% and 0.3%, respectively) as compared to non-manual/white-collar workers (7.3%, 0.8%, 0.8% and 0.3%, respectively). Age- and sex-adjusted prevalence rates of IFG, UKDM and KDM2 were 13.1%, 2.0% and 2.4%, respectively. In this sample of Spanish working population, impaired glycemic profiles were common. Prevalence rates of IFG and T2DM were high among blue-collar workers (except for T1DM). These data emphasize the need for earlier structured preventive schemes. Copyright © 2016 SEEN. Published by Elsevier España, S.L.U. All rights reserved.

Military milk: breastfeeding rates among Australian Defence Force women who return to military service following maternity leave.

PubMed

Stewart, Kelley

2015-02-01

The breastfeeding behaviors among Australian Defence Force women have not previously been examined. Studies have shown that breastfeeding prevalence and duration are affected by maternity leave entitlements and returning to work. This study aimed to benchmark breastfeeding initiation, prevalence, and duration among a cohort of Australian Defence Force women and to compare these findings against Australian population norms. A cross-sectional survey was conducted via email in 2008 for Australian Defence Force women who had taken maternity leave in the Australian financial year of 2006/2007. Analysis of breastfeeding indicators was undertaken. Ninety-eight percent of Australian Defence Force women in this cohort initiated breastfeeding and breastfed for a median duration of 8 months, returning to work when the mean age of the child was 8.4 months. Breastfeeding prevalence did not meet 2003 Australian National Health and Medical Research Council targets by 6 months postpartum but compared favorably to the Australian population norms. Sixty-six percent of the respondents returned to work full-time, with a median breastfeeding duration of 7 months. Women who returned to work part-time had a longer median duration of 10 months. Breastfeeding rates among this cohort of Australian Defence Force women compare favorably with the general Australian population until 9 months, coinciding with returning to work after a period of maternity leave. The results support recent Australian population studies on breastfeeding and employment. © The Author(s) 2014.

TOTALL: high cost of allergic rhinitis-a national Swedish population-based questionnaire study.

PubMed

Cardell, Lars-Olaf; Olsson, Petter; Andersson, Morgan; Welin, Karl-Olof; Svensson, Johanna; Tennvall, Gunnel Ragnarson; Hellgren, Johan

2016-02-04

Allergic rhinitis is a global illness with a well-recognised impact on quality of life and work performance. Comparatively little is known about the extent of its economic impact on society. The TOTALL study estimates the total cost of allergic rhinitis using a sample representing the entire Swedish population of working age. A questionnaire focused on allergic rhinitis was mailed out to a random population of Swedish residents, aged 18-65 years. Health-care contacts, medications, absenteeism (absence from work) and presenteeism (reduced working capacity at work) were assessed, and the direct and indirect costs of allergic rhinitis were calculated. Medication use was evaluated in relation to the ARIA guidelines. In all, 3,501 of 8,001 (44%) answered the questionnaire, and 855 (24%) of these reported allergic rhinitis. The mean annual direct and indirect costs because of allergic rhinitis were €210.3 and €750.8, respectively, resulting in a total cost of €961.1 per individual/year. Presenteeism represented 70% of the total cost. Antihistamines appear to be used in excess in relation to topical steroids, and the use of nasal decongestants was alarmingly high. The total cost of allergic rhinitis in Sweden, with a population of 9.5 million, was estimated at €1.3 billion annually. These unexpectedly high costs could be related to the high prevalence of disease, in combination with the previously often underestimated indirect costs. Improved adherence to guidelines might ease the economic burden on society.

Adaptation to larval crowding in Drosophila ananassae leads to the evolution of population stability.

PubMed

Dey, Snigdhadip; Bose, Joy; Joshi, Amitabh

2012-05-01

Density-dependent selection is expected to lead to population stability, especially if r and K tradeoff. Yet, there is no empirical evidence of adaptation to crowding leading to the evolution of stability. We show that populations of Drosophila ananassae selected for adaptation to larval crowding have higher K and lower r, and evolve greater stability than controls. We also show that increased population growth rates at high density can enhance stability, even in the absence of a decrease in r, by ensuring that the crowding adapted populations do not fall to very low sizes. We discuss our results in the context of traits known to have diverged between the selected and control populations, and compare our results with previous work on the evolution of stability in D. melanogaster. Overall, our results suggest that density-dependent selection may be an important factor promoting the evolution of relatively stable dynamics in natural populations.

Colic in a working horse population in Egypt: Prevalence and risk factors.

PubMed

Salem, S E; Scantlebury, C E; Ezzat, E; Abdelaal, A M; Archer, D C

2017-03-01

Colic is an important health problem in managed horse populations. Currently, there is limited information about colic prevalence and risk factors for colic in working horse populations. To determine the prevalence of, and risk factors for, colic in a working horse population in Egypt and to describe management practices in this working horse population. Cross-sectional survey. Owners of 350 working horses were interviewed. Data about their horses, management and colic episodes in the preceding 12 months were collected. Dental examination was conducted on 342 horses and blood samples (n = 100) were collected for immunodiagnosis of tapeworm (Anoplocephala perfoliata) infection. Multivariable logistic regression analysis was used to identify risk factors for a history of colic in the preceding 12 months. The 12-month prevalence of colic was 54.6%. Severe and moderate tapeworm infection intensity was identified in 3% and 26% of horses tested, respectively. Horses that had severe dental disease (odds ratio [OR] 6.8, 95% confidence interval [CI] 1.9-24.3, P<0.001), that displayed stereotypic behaviour (OR 2.0, 95% CI 1.15-3.5, P = 0.013), were fed ground corn during the 'dry season' (OR 1.65, 95% CI 1.03-2.6, P = 0.035) or that had received an anthelmintic in the previous 6 months (OR 2.1, 95% CI 1.3-3.3, P = 0.003) were more likely to have a history of colic in the preceding 12 months. Horses fed on rice bran during the 'green season' (OR 0.47, 95% CI 0.26-0.9, P = 0.015) and that displayed geophagia/coprophagia (OR 0.19, 95% CI 0.05-0.73, P = 0.001) were less likely to have a history of colic. Colic is common in this working horse population and this study has identified factors associated with altered likelihood of colic. The study provides important information that may be used to inform future prospective studies investigating colic in working horse populations and to assist development of preventive healthcare strategies. The Summary is available in Chinese - see Supporting information. © 2016 EVJ Ltd.

Analysis of mitochondrial DNA in Bolivian llama, alpaca and vicuna populations: a contribution to the phylogeny of the South American camelids.

PubMed

Barreta, J; Gutiérrez-Gil, B; Iñiguez, V; Saavedra, V; Chiri, R; Latorre, E; Arranz, J J

2013-04-01

The objectives of this work were to assess the mtDNA diversity of Bolivian South American camelid (SAC) populations and to shed light on the evolutionary relationships between the Bolivian camelids and other populations of SACs. We have analysed two different mtDNA regions: the complete coding region of the MT-CYB gene and 513 bp of the D-loop region. The populations sampled included Bolivian llamas, alpacas and vicunas, and Chilean guanacos. High levels of genetic diversity were observed in the studied populations. In general, MT-CYB was more variable than D-loop. On a species level, the vicunas showed the lowest genetic variability, followed by the guanacos, alpacas and llamas. Phylogenetic analyses performed by including additional available mtDNA sequences from the studied species confirmed the existence of the two monophyletic clades previously described by other authors for guanacos (G) and vicunas (V). Significant levels of mtDNA hybridization were found in the domestic species. Our sequence analyses revealed significant sequence divergence within clade G, and some of the Bolivian llamas grouped with the majority of the southern guanacos. This finding supports the existence of more than the one llama domestication centre in South America previously suggested on the basis of archaeozoological evidence. Additionally, analysis of D-loop sequences revealed two new matrilineal lineages that are distinct from the previously reported G and V clades. The results presented here represent the first report on the population structure and genetic variability of Bolivian camelids and may help to elucidate the complex and dynamic domestication process of SAC populations. © 2012 The Authors, Animal Genetics © 2012 Stichting International Foundation for Animal Genetics.

Mitochondrial DNA analysis shows a Near Eastern Neolithic origin for domestic cattle and no indication of domestication of European aurochs.

PubMed

Edwards, Ceiridwen J; Bollongino, Ruth; Scheu, Amelie; Chamberlain, Andrew; Tresset, Anne; Vigne, Jean-Denis; Baird, Jillian F; Larson, Greger; Ho, Simon Y W; Heupink, Tim H; Shapiro, Beth; Freeman, Abigail R; Thomas, Mark G; Arbogast, Rose-Marie; Arndt, Betty; Bartosiewicz, László; Benecke, Norbert; Budja, Mihael; Chaix, Louis; Choyke, Alice M; Coqueugniot, Eric; Döhle, Hans-Jürgen; Göldner, Holger; Hartz, Sönke; Helmer, Daniel; Herzig, Barabara; Hongo, Hitomi; Mashkour, Marjan; Ozdogan, Mehmet; Pucher, Erich; Roth, Georg; Schade-Lindig, Sabine; Schmölcke, Ulrich; Schulting, Rick J; Stephan, Elisabeth; Uerpmann, Hans-Peter; Vörös, István; Voytek, Barbara; Bradley, Daniel G; Burger, Joachim

2007-06-07

The extinct aurochs (Bos primigenius primigenius) was a large type of cattle that ranged over almost the whole Eurasian continent. The aurochs is the wild progenitor of modern cattle, but it is unclear whether European aurochs contributed to this process. To provide new insights into the demographic history of aurochs and domestic cattle, we have generated high-confidence mitochondrial DNA sequences from 59 archaeological skeletal finds, which were attributed to wild European cattle populations based on their chronological date and/or morphology. All pre-Neolithic aurochs belonged to the previously designated P haplogroup, indicating that this represents the Late Glacial Central European signature. We also report one new and highly divergent haplotype in a Neolithic aurochs sample from Germany, which points to greater variability during the Pleistocene. Furthermore, the Neolithic and Bronze Age samples that were classified with confidence as European aurochs using morphological criteria all carry P haplotype mitochondrial DNA, suggesting continuity of Late Glacial and Early Holocene aurochs populations in Europe. Bayesian analysis indicates that recent population growth gives a significantly better fit to our data than a constant-sized population, an observation consistent with a postglacial expansion scenario, possibly from a single European refugial population. Previous work has shown that most ancient and modern European domestic cattle carry haplotypes previously designated T. This, in combination with our new finding of a T haplotype in a very Early Neolithic site in Syria, lends persuasive support to a scenario whereby gracile Near Eastern domestic populations, carrying predominantly T haplotypes, replaced P haplotype-carrying robust autochthonous aurochs populations in Europe, from the Early Neolithic onward. During the period of coexistence, it appears that domestic cattle were kept separate from wild aurochs and introgression was extremely rare.

Doubling over ten years of central obesity in Hong Kong Chinese working men.

PubMed

Ko, Tin-choi Gary; Chan, Juliana; Chan, Amy; Wong, Patrick; Hui, Stanley; Chow, Ferrie; Tong, Spencer; Chan, Cecilia

2007-07-05

Obesity is now an epidemic in most parts of the world. In this cross sectional study, we report the most recent data on obesity in Hong Kong Chinese working population and compare the changes over 10 years. Between July 2000 and March 2002, 5882 adult subjects from the working class in Hong Kong were recruited (2716 men (46.2%) and 3166 women (53.8%)). They were randomly selected using computer generated codes according to the distribution of occupational groups. Results of this study were compared with the data collected from a prevalence survey for cardiovascular risk factors in a Hong Kong Chinese working population conducted in 1990 (1513 subjects, 910 men (60.1%) and 603 women (39.9%)). Standardized percentages of overweight, obesity, and central obesity, in Hong Kong Chinese working population were 59.7%, 35.0%, 26.7% in men and 32.0%, 21.7%, 26.7% in women. Compared to the data collected in 1990, the percentage of obesity increased by 5% in men and reduced by 6% in women. The percentage of central obesity doubled in men (from 12.2% to 26.7%) but remained stable in women. There is a doubling of the percentage of central obesity in Hong Kong Chinese working men over previous decade. Education and proper lifestyle modification program to tackle this social health issue are urgently indicated.

Disparities in Insurance Coverage, Health Services Use, and Access Following Implementation of the Affordable Care Act: A Comparison of Disabled and Nondisabled Working-Age Adults.

PubMed

Kennedy, Jae; Wood, Elizabeth Geneva; Frieden, Lex

2017-01-01

The objective of this study was to assess trends in health insurance coverage, health service utilization, and health care access among working-age adults with and without disabilities before and after full implementation of the Affordable Care Act (ACA), and to identify current disability-based disparities following full implementation of the ACA. The ACA was expected to have a disproportionate impact on working-age adults with disabilities, because of their high health care usage as well as their previously limited insurance options. However, most published research on this population does not systematically look at effects before and after full implementation of the ACA. As the US Congress considers new health policy reforms, current and accurate data on this vulnerable population are essential. Weighted estimates, trend analyses and analytic models were conducted using the 1998-2016 National Health Interview Surveys (NHIS) and the 2014 Medical Expenditure Panel Survey. Compared with working-age adults without disabilities, those with disabilities are less likely to work, more likely to earn below the federal poverty level, and more likely to use public insurance. Average health costs for this population are 3 to 7 times higher, and access problems are far more common. Repeal of key features of the ACA, like Medicaid expansion and marketplace subsidies, would likely diminish health care access for working-age adults with disabilities.

Genetic origin, admixture and population history of aurochs (Bos primigenius) and primitive European cattle

PubMed Central

Upadhyay, M R; Chen, W; Lenstra, J A; Goderie, C R J; MacHugh, D E; Park, S D E; Magee, D A; Matassino, D; Ciani, F; Megens, H-J; van Arendonk, J A M; Groenen, M A M; Marsan, P A; Balteanu, V; Dunner, S; Garcia, J F; Ginja, C; Kantanen, J

2017-01-01

The domestication of taurine cattle initiated ~10 000 years ago in the Near East from a wild aurochs (Bos primigenius) population followed by their dispersal through migration of agriculturalists to Europe. Although gene flow from wild aurochs still present at the time of this early dispersion is still debated, some of the extant primitive cattle populations are believed to possess the aurochs-like primitive features. In this study, we use genome-wide single nucleotide polymorphisms to assess relationship, admixture patterns and demographic history of an ancient aurochs sample and European cattle populations, several of which have primitive features and are suitable for extensive management. The principal component analysis, the model-based clustering and a distance-based network analysis support previous works suggesting different histories for north-western and southern European cattle. Population admixture analysis indicates a zebu gene flow in the Balkan and Italian Podolic cattle populations. Our analysis supports the previous report of gene flow between British and Irish primitive cattle populations and local aurochs. In addition, we show evidence of aurochs gene flow in the Iberian cattle populations indicating wide geographical distribution of the aurochs. Runs of homozygosity (ROH) reveal that demographic processes like genetic isolation and breed formation have contributed to genomic variations of European cattle populations. The ROH also indicate recent inbreeding in southern European cattle populations. We conclude that in addition to factors such as ancient human migrations, isolation by distance and cross-breeding, gene flow between domestic and wild-cattle populations also has shaped genomic composition of European cattle populations. PMID:27677498

Genetic origin, admixture and population history of aurochs (Bos primigenius) and primitive European cattle.

PubMed

Upadhyay, M R; Chen, W; Lenstra, J A; Goderie, C R J; MacHugh, D E; Park, S D E; Magee, D A; Matassino, D; Ciani, F; Megens, H-J; van Arendonk, J A M; Groenen, M A M

2017-02-01

The domestication of taurine cattle initiated ~10 000 years ago in the Near East from a wild aurochs (Bos primigenius) population followed by their dispersal through migration of agriculturalists to Europe. Although gene flow from wild aurochs still present at the time of this early dispersion is still debated, some of the extant primitive cattle populations are believed to possess the aurochs-like primitive features. In this study, we use genome-wide single nucleotide polymorphisms to assess relationship, admixture patterns and demographic history of an ancient aurochs sample and European cattle populations, several of which have primitive features and are suitable for extensive management. The principal component analysis, the model-based clustering and a distance-based network analysis support previous works suggesting different histories for north-western and southern European cattle. Population admixture analysis indicates a zebu gene flow in the Balkan and Italian Podolic cattle populations. Our analysis supports the previous report of gene flow between British and Irish primitive cattle populations and local aurochs. In addition, we show evidence of aurochs gene flow in the Iberian cattle populations indicating wide geographical distribution of the aurochs. Runs of homozygosity (ROH) reveal that demographic processes like genetic isolation and breed formation have contributed to genomic variations of European cattle populations. The ROH also indicate recent inbreeding in southern European cattle populations. We conclude that in addition to factors such as ancient human migrations, isolation by distance and cross-breeding, gene flow between domestic and wild-cattle populations also has shaped genomic composition of European cattle populations.

Rapid divergence and convergence of life-history in experimentally evolved Drosophila melanogaster.

PubMed

Burke, Molly K; Barter, Thomas T; Cabral, Larry G; Kezos, James N; Phillips, Mark A; Rutledge, Grant A; Phung, Kevin H; Chen, Richard H; Nguyen, Huy D; Mueller, Laurence D; Rose, Michael R

2016-09-01

Laboratory selection experiments are alluring in their simplicity, power, and ability to inform us about how evolution works. A longstanding challenge facing evolution experiments with metazoans is that significant generational turnover takes a long time. In this work, we present data from a unique system of experimentally evolved laboratory populations of Drosophila melanogaster that have experienced three distinct life-history selection regimes. The goal of our study was to determine how quickly populations of a certain selection regime diverge phenotypically from their ancestors, and how quickly they converge with independently derived populations that share a selection regime. Our results indicate that phenotypic divergence from an ancestral population occurs rapidly, within dozens of generations, regardless of that population's evolutionary history. Similarly, populations sharing a selection treatment converge on common phenotypes in this same time frame, regardless of selection pressures those populations may have experienced in the past. These patterns of convergence and divergence emerged much faster than expected, suggesting that intermediate evolutionary history has transient effects in this system. The results we draw from this system are applicable to other experimental evolution projects, and suggest that many relevant questions can be sufficiently tested on shorter timescales than previously thought. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

Association among Working Hours, Occupational Stress, and Presenteeism among Wage Workers: Results from the Second Korean Working Conditions Survey.

PubMed

Jeon, Sung-Hwan; Leem, Jong-Han; Park, Shin-Goo; Heo, Yong-Seok; Lee, Bum-Joon; Moon, So-Hyun; Jung, Dal-Young; Kim, Hwan-Cheol

2014-03-24

The purpose of the present study was to identify the association between presenteeism and long working hours, shiftwork, and occupational stress using representative national survey data on Korean workers. We analyzed data from the second Korean Working Conditions Survey (KWCS), which was conducted in 2010, in which a total of 6,220 wage workers were analyzed. The study population included the economically active population aged above 15 years, and living in the Republic of Korea. We used the chi-squared test and multivariate logistic regression to test the statistical association between presenteeism and working hours, shiftwork, and occupational stress. Approximately 19% of the workers experienced presenteeism during the previous 12 months. Women had higher rates of presenteeism than men. We found a statistically significant dose-response relationship between working hours and presenteeism. Shift workers had a slightly higher rate of presenteeism than non-shift workers, but the difference was not statistically significant. Occupational stress, such as high job demand, lack of rewards, and inadequate social support, had a significant association with presenteeism. The present study suggests that long working hours and occupational stress are significantly related to presenteeism.

Association among Working Hours, Occupational Stress, and Presenteeism among Wage Workers: Results from the Second Korean Working Conditions Survey

PubMed Central

2014-01-01

Objectives The purpose of the present study was to identify the association between presenteeism and long working hours, shiftwork, and occupational stress using representative national survey data on Korean workers. Methods We analyzed data from the second Korean Working Conditions Survey (KWCS), which was conducted in 2010, in which a total of 6,220 wage workers were analyzed. The study population included the economically active population aged above 15 years, and living in the Republic of Korea. We used the chi-squared test and multivariate logistic regression to test the statistical association between presenteeism and working hours, shiftwork, and occupational stress. Results Approximately 19% of the workers experienced presenteeism during the previous 12 months. Women had higher rates of presenteeism than men. We found a statistically significant dose–response relationship between working hours and presenteeism. Shift workers had a slightly higher rate of presenteeism than non-shift workers, but the difference was not statistically significant. Occupational stress, such as high job demand, lack of rewards, and inadequate social support, had a significant association with presenteeism. Conclusions The present study suggests that long working hours and occupational stress are significantly related to presenteeism. PMID:24661575

Explaining the social gradient in sickness absence: a study of a general working population in Sweden.

PubMed

Löve, Jesper; Hensing, Gunnel; Holmgren, Kristina; Torén, Kjell

2013-06-05

Some previous studies have proposed potential explanatory factors for the social gradient in sickness absence. Yet, this research area is still in its infancy and in order to comprise the full range of socioeconomic positions there is a need for studies conducted on random population samples. The main aim of the present study was to investigate if somatic and mental symptoms, mental wellbeing, job strain, and physical work environment could explain the association between low socioeconomic position and belonging to a sample of new cases of sick-listed employees. This study was conducted on one random working population sample (n = 2763) and one sample of newly sick-listed cases of employees (n = 3044), drawn from the same random general population in western Sweden. Explanatory factors were self-rated 'Somatic and mental symptoms', 'Mental well-being', 'job strain', and 'physical work conditions' (i.e. heavy lifting and awkward work postures). Multiple logistic regression analyses were used. Somatic and mental symptoms, mental well-being, and job strain, could not explain the association between socioeconomic position and sickness absence in both women and men. However, physical work conditions explained the total association in women and much of this association in men. In men the gradient between Non-skilled manual OR 1.76 (1.24;2.48) and Skilled manual OR 1.59 (1.10;2.20), both in relation to Higher non-manual, remained unexplained. The present study strengthens the scientific evidence that social differences in physical work conditions seem to comprise a key element of the social gradient in sickness absence, particularly in women. Future studies should try to identify further predictors for this gradient in men.

Effects of population density on corticosterone levels of prairie voles in the field.

PubMed

Blondel, Dimitri V; Wallace, Gerard N; Calderone, Stefanie; Gorinshteyn, Marija; St Mary, Colette M; Phelps, Steven M

2016-01-01

High population density is often associated with increased levels of stress-related hormones, such as corticosterone (CORT). Prairie voles (Microtus ochrogaster) are a socially monogamous species known for their large population density fluctuations in the wild. Although CORT influences the social behavior of prairie voles in the lab, the effect of population density on CORT has not previously been quantified in this species in the field. We validated a non-invasive hormone assay for measuring CORT metabolites in prairie vole feces. We then used semi-natural enclosures to experimentally manipulate population density, and measured density effects on male space use and fecal CORT levels. Our enclosures generated patterns of space use and social interaction that were consistent with previous prairie vole field studies. Contrary to the positive relationship between CORT and density typical of other taxa, we found that lower population densities (80 animals/ha) produced higher fecal CORT than higher densities (240/ha). Combined with prior work in the lab and field, the data suggest that high prairie vole population densities indicate favorable environments, perhaps through reduced predation risk. Lastly, we found that field animals had lower fecal CORT levels than laboratory-living animals. The data emphasize the usefulness of prairie voles as models for integrating ecological, evolutionary, and mechanistic questions in social behavior. Copyright © 2015 Elsevier Inc. All rights reserved.

Using Palm Technology in Participatory Simulations of Complex Systems: A New Take on Ubiquitous and Accessible Mobile Computing

ERIC Educational Resources Information Center

Klopfer, Eric; Yoon, Susan; Perry, Judy

2005-01-01

This paper reports on teachers' perceptions of the educational affordances of a handheld application called Participatory Simulations. It presents evidence from five cases representing each of the populations who work with these computational tools. Evidence across multiple data sources yield similar results to previous research evaluations of…

Field and laboratory approaches to understanding testicular oocytes and gonadal development in smallmouth bass in relation to exposure to EACs

EPA Science Inventory

In previous work we reported smallmouth bass populations in Northeastern Minnesota rivers and lakes with testicular oocyte (TOs) prevalence ranging from 7 to 59%, which is consistent with reports from other U.S. river systems. While it is often presumed that TOs are associated wi...

Sleep Quality and Alcohol Risk in College Students: Examining the Moderating Effects of Drinking Motives

ERIC Educational Resources Information Center

Kenney, Shannon R.; Paves, Andrew P.; Grimaldi, Elizabeth M.; LaBrie, Joseph W.

2014-01-01

Objective: Sleep problems and alcohol misuse are common issues experienced by college students that can have detrimental effects on overall health. Previous work indicates a strong relationship between poor sleep quality and alcohol risk in this population. This study explored the moderating effect of drinking motives in the relationship between…

Maternal Pre-Pregnancy Obesity and Risk for Inattention and Negative Emotionality in Children

ERIC Educational Resources Information Center

Rodriguez, Alina

2010-01-01

Objective: This study aimed to replicate and extend previous work showing an association between maternal pre-pregnancy adiposity and risk for attention deficit hyperactivity disorder (ADHD) symptoms in children. Methods: A Swedish population-based prospective pregnancy-offspring cohort was followed up when children were 5 years old (N = 1,714).…

Relations among Grade 4 Students' Perceptions of Autonomy, Engagement in Science, and Reading Motivation

ERIC Educational Resources Information Center

Taboada Barber, Ana; Buehl, Michelle M.

2013-01-01

The authors extend previous work on students' perceptions of teachers' autonomy-enhancing and autonomy-suppressing behaviors in relation to students' engagement to a more situated context (i.e., two Grade 4 science instructional conditions instead of school in general) and a linguistically diverse population (i.e., Hispanic students). They also…

Prevalence and associated factors of pinguecula in a rural population in Shanghai, Eastern China.

PubMed

Le, Qihua; Xiang, Jun; Cui, Xinhan; Zhou, Xiaodong; Xu, Jianjiang

2015-04-01

To determine the prevalence and associated factors of pinguecula in a rural Chinese population aged ≥ 50 years in Eastern China. This cross-sectional, population-based survey included an age-stratified random sample of 1108 residents living in Lvxiang Town of Jinshan District. Participants were requested to complete a comprehensive questionnaire to collect demographic data, history of systemic diseases and lifestyle details. The presence of pinguecula on slit lamp examination was recorded. The prevalence of pinguecula and its associated factors were investigated by logistic regression models. Among 1108 eligible subjects, 959 participated in the study, with an average age of 65.1 ± 9.2 years (range 50-89 years). The overall age-adjusted prevalence of pinguecula in this population was 75.57% (95% confidence interval 71.79-79.35%). Logistic regression analysis revealed that age (p = 0.002) and working outdoors (daily sunlight exposure ≥ 2 hours; p = 0.001) were independent risk factors for pinguecula. In addition, sex, education level, alcohol intake, smoking and decreased tear break-up time did not have associations with the development of pinguecula after adjusting for age and outdoor work occupations. The prevalence of pinguecula was 75.57% in this Chinese population aged ≥ 50 years from a coastal rural area of Shanghai, Eastern China, which was higher than the majority of previous findings. Age and working outdoors were independent risk factors for pinguecula.

Who wants to work with older people? Swedish student nurses' willingness to work in elderly care--a questionnaire study.

PubMed

Carlson, Elisabeth; Idvall, Ewa

2015-07-01

The aging population is a globally recognized challenge for the health care service. The growing number of older people will probably lead to increased demands for nurses working in elderly care. Clinical practice has been shown to have an impact on how student nurses perceive a particular field of nursing. To compare perceptions of the clinical learning environment in nursing homes among students considering a career in aged care or not, and to examine the difference in age, gender and previous working experience as health care assistants in elderly care between the two groups. This was a cross-sectional study using the Swedish version of the Clinical Learning Environment and Nurse Teacher evaluation scale. Consecutive sampling was performed over three semesters from September 2011 to December 2012. The survey was conducted with 183 student nurses. Mann-Whitney U-test was used to examine differences in relation to two groups namely student nurses who did or did not consider to work in elderly care. A chi-square test of independence was performed to examine the difference in age, gender and previous working experience between the two groups. The analysis leaned towards an overall positive evaluation of the clinical learning environment with more positive values for students considering a career. There were no significant differences between younger students (18-23) and older students (24-50) regarding willingness to work in elderly care or not. Neither was any significant difference displayed between students, based on gender nor for previous work experience. Age, gender and previous work experiences as health care assistants did not impact on students' willingness to work in elderly care. Future studies need to acknowledge the complexity of why student nurses choose a particular pathway in nursing by longitudinal studies following cohorts of students during the course of the nursing programme. Copyright © 2015 Elsevier Ltd. All rights reserved.

Projection specificity in heterogeneous locus coeruleus cell populations: implications for learning and memory

PubMed Central

Uematsu, Akira; Tan, Bao Zhen

2015-01-01

Noradrenergic neurons in the locus coeruleus (LC) play a critical role in many functions including learning and memory. This relatively small population of cells sends widespread projections throughout the brain including to a number of regions such as the amygdala which is involved in emotional associative learning and the medial prefrontal cortex which is important for facilitating flexibility when learning rules change. LC noradrenergic cells participate in both of these functions, but it is not clear how this small population of neurons modulates these partially distinct processes. Here we review anatomical, behavioral, and electrophysiological studies to assess how LC noradrenergic neurons regulate these different aspects of learning and memory. Previous work has demonstrated that subpopulations of LC noradrenergic cells innervate specific brain regions suggesting heterogeneity of function in LC neurons. Furthermore, noradrenaline in mPFC and amygdala has distinct effects on emotional learning and cognitive flexibility. Finally, neural recording data show that LC neurons respond during associative learning and when previously learned task contingencies change. Together, these studies suggest a working model in which distinct and potentially opposing subsets of LC neurons modulate particular learning functions through restricted efferent connectivity with amygdala or mPFC. This type of model may provide a general framework for understanding other neuromodulatory systems, which also exhibit cell type heterogeneity and projection specificity. PMID:26330494

Professions and Working Conditions Associated With Community-Acquired Pneumonia.

PubMed

Almirall, Jordi; Serra-Prat, Mateu; Bolíbar, Ignasi; Palomera, Elisabet; Roig, Jordi; Boixeda, Ramon; Bartolomé, Maria; de la Torre, Mari; Parra, Olga; Torres, Antoni

2015-12-01

Community-acquired pneumonia (CAP) is not considered a professional disease, and the effect of different occupations and working conditions on susceptibility to CAP is unknown. The aim of this study is to determine whether different jobs and certain working conditions are risk factors for CAP. Over a 1-year period, all radiologically confirmed cases of CAP (n=1,336) and age- and sex-matched controls (n=1,326) were enrolled in a population-based case-control study. A questionnaire on CAP risk factors, including work-related questions, was administered to all participants during an in-person interview. The bivariate analysis showed that office work is a protective factor against CAP, while building work, contact with dust and sudden changes of temperature in the workplace were risk factors for CAP. The occupational factor disappeared when the multivariate analysis was adjusted for working conditions. Contact with dust (previous month) and sudden changes of temperature (previous 3 months) were risk factors for CAP, irrespective of the number of years spent working in these conditions, suggesting reversibility. Some recent working conditions such as exposure to dust and sudden changes of temperature in the workplace are risk factors for CAP. Both factors are reversible and preventable. Copyright © 2014 SEPAR. Published by Elsevier Espana. All rights reserved.

Pitfalls, Potentials, and Ethics of Online Survey Research: LGBTQ and Other Marginalized and Hard-to-Access Youths

PubMed Central

McInroy, Lauren B.

2016-01-01

Online research methodologies may serve as an important mechanism for population-focused data collection in social work research. Online surveys have become increasingly prevalent in research inquiries with young people and have been acknowledged for their potential in investigating understudied and marginalized populations and subpopulations, permitting increased access to communities that tend to be less visible—and thus often less studied—in offline contexts. Lesbian, gay, bisexual, transgender, and queer (LGBTQ) young people are a socially stigmatized, yet digitally active, youth population whose participation in online surveys has been previously addressed in the literature. Many of the opportunities and challenges of online survey research identified with LGBTQ youths may be highly relevant to other populations of marginalized and hard-to-access young people, who are likely present in significant numbers in the online environment (for example, ethnoracialized youths and low-income youths). In this article, the utility of online survey methods with marginalized young people is discussed, and recommendations for social work research are provided. PMID:27257362

Integration of multiple determinants in the neuronal computation of economic values.

PubMed

Raghuraman, Anantha P; Padoa-Schioppa, Camillo

2014-08-27

Economic goods may vary on multiple dimensions (determinants). A central conjecture in decision neuroscience is that choices between goods are made by comparing subjective values computed through the integration of all relevant determinants. Previous work identified three groups of neurons in the orbitofrontal cortex (OFC) of monkeys engaged in economic choices: (1) offer value cells, which encode the value of individual offers; (2) chosen value cells, which encode the value of the chosen good; and (3) chosen juice cells, which encode the identity of the chosen good. In principle, these populations could be sufficient to generate a decision. Critically, previous work did not assess whether offer value cells (the putative input to the decision) indeed encode subjective values as opposed to physical properties of the goods, and/or whether offer value cells integrate multiple determinants. To address these issues, we recorded from the OFC while monkeys chose between risky outcomes. Confirming previous observations, three populations of neurons encoded the value of individual offers, the value of the chosen option, and the value-independent choice outcome. The activity of both offer value cells and chosen value cells encoded values defined by the integration of juice quantity and probability. Furthermore, both populations reflected the subjective risk attitude of the animals. We also found additional groups of neurons encoding the risk associated with a particular option, the risky nature of the chosen option, and whether the trial outcome was positive or negative. These results provide substantial support for the conjecture described above and for the involvement of OFC in good-based decisions. Copyright © 2014 the authors 0270-6474/14/3311583-21$15.00/0.

Reconstructing the Phylogenetic History of Long-Term Effective Population Size and Life-History Traits Using Patterns of Amino Acid Replacement in Mitochondrial Genomes of Mammals and Birds

PubMed Central

Nabholz, Benoit; Lartillot, Nicolas

2013-01-01

The nearly neutral theory, which proposes that most mutations are deleterious or close to neutral, predicts that the ratio of nonsynonymous over synonymous substitution rates (dN/dS), and potentially also the ratio of radical over conservative amino acid replacement rates (Kr/Kc), are negatively correlated with effective population size. Previous empirical tests, using life-history traits (LHT) such as body-size or generation-time as proxies for population size, have been consistent with these predictions. This suggests that large-scale phylogenetic reconstructions of dN/dS or Kr/Kc might reveal interesting macroevolutionary patterns in the variation in effective population size among lineages. In this work, we further develop an integrative probabilistic framework for phylogenetic covariance analysis introduced previously, so as to estimate the correlation patterns between dN/dS, Kr/Kc, and three LHT, in mitochondrial genomes of birds and mammals. Kr/Kc displays stronger and more stable correlations with LHT than does dN/dS, which we interpret as a greater robustness of Kr/Kc, compared with dN/dS, the latter being confounded by the high saturation of the synonymous substitution rate in mitochondrial genomes. The correlation of Kr/Kc with LHT was robust when controlling for the potentially confounding effects of nucleotide compositional variation between taxa. The positive correlation of the mitochondrial Kr/Kc with LHT is compatible with previous reports, and with a nearly neutral interpretation, although alternative explanations are also possible. The Kr/Kc model was finally used for reconstructing life-history evolution in birds and mammals. This analysis suggests a fairly large-bodied ancestor in both groups. In birds, life-history evolution seems to have occurred mainly through size reduction in Neoavian birds, whereas in placental mammals, body mass evolution shows disparate trends across subclades. Altogether, our work represents a further step toward a more comprehensive phylogenetic reconstruction of the evolution of life-history and of the population-genetics environment. PMID:23711670

True polyandry and pseudopolyandry: why does a monandrous fly remate?

PubMed

Fisher, David N; Doff, Rowan J; Price, Tom A R

2013-07-25

The rate of female remating can have important impacts on a species, from affecting conflict and cooperation within families, to population viability and gene flow. However, determining the level of polyandry in a species can be difficult, with information on the mating system of many species being based on a single experiment, or completely absent. Here we investigate the mating system of the fruit fly Drosophila subobscura. Reports from England, Spain and Canada suggest D. subobscura is entirely monandrous, with no females remating. However, work in Greece suggests that 23% of females remate. We examine the willingness of female D. subobscura to remate in the laboratory in a range of conditions, using flies from both Greece and England. We make a distinction between pseudopolyandry, where a female remates after an ineffective first mating that is incapable of fertilising her eggs, and true polyandry, where a female remates even though she has received suitable sperm from a previous mating. We find a low rate of true polyandry by females (4%), with no difference between populations. The rate of true polyandry is affected by temperature, but not starvation. Pseudopolyandry is three times as common as true polyandry, and most females showing pseudopolyandry mated at their first opportunity after their first failed mating. However, despite the lack of differences in polyandry between the populations, we do find differences in the way males respond to exposure to other males prior to mating. In line with previous work, English flies responded to one or more rivals by increasing their copulation duration, a response previously thought to be driven by sperm competition. Greek males only show increased copulation duration when exposed to four or more rival males. This suggests that the response to rivals in D. subobscura is not related to sperm competition, because sperm competition is rare, and there is no correlation of response to rivals and mating system across the populations. These results illustrate the difficulties in determining the mating system of a species, even one that is well known and an excellent laboratory species, with results being highly dependent on the conditions used to assay the behaviour, and the population used.

An historical perspective on "The world-wide distribution of allele frequencies at the human dopamine D4 receptor locus".

PubMed

Kidd, Kenneth K; Pakstis, Andrew J; Yun, Libing

2014-04-01

Human population genetics is a completely different science today compared to two decades ago, at least at the empiric level. Our paper [Chang (Hum Genet 98:91-101, 1996a)] demonstrated that three different alleles were common when one considered many populations although other low frequency alleles occurred. Because previous work had been largely done on European subjects, our findings involved 36 distinct populations and showed that East Asian populations had nearly lost the 7-repeat allele, and that Native American populations had the highest frequencies of that allele globally, was a significant early empiric demonstration of the potential magnitude of population variation at important genes. There are thousands of loci tested on many of the same populations and the gene frequency pattern seen for the DRD4 7-repeat allele is seen at other loci, arguing that this pattern commonly reflects the pattern of divergence of populations and accumulated random genetic drift.

Emotion, working memory, and cognitive control in patients with first-onset and previously untreated minor depressive disorders.

PubMed

Li, Mi; Lu, Shengfu; Wang, Gang; Feng, Lei; Fu, Bingbing; Zhong, Ning

2016-06-01

To explore working memory and the ability to process different emotional stimuli in patients with first-onset and untreated minor (mild or moderate) depression. Patients with first-onset and previously untreated minor depression, and healthy controls, were enrolled. Using a modified Sternberg working memory paradigm to investigate the combined effects of emotional stimuli with working memory, participants were exposed to experimental stimuli comprising pictures that represented positive, neutral and negative emotions. Working memory ability was measured using reaction time and accuracy, and emotion-processing ability was measured using pupil diameter. Out of 36 participants (18 patients with minor depression and 18 controls), there were no statistically significant between-group differences in response time and accuracy. Positive stimuli evoked changes in pupil diameter that were significantly smaller in patients with minor depression versus controls, but changes in pupil diameter evoked by negative stimuli were not significantly different between the two groups. Healthy subjects showed a stronger emotional response to positive emotional stimuli than patients with first onset and previously untreated minor depression, but there were no differences in response to negative emotions. There were no statistically significant between-group differences in terms of speed of cognitive response, but this may have been due to the relatively small samples sizes assessed. Studies with larger sample populations are required to further investigate these results. © The Author(s) 2016.

Nonlinear saturation of the Weibel instability

DOE PAGES

Cagas, P.; Hakim, A.; Scales, W.; ...

2017-11-21

The growth and saturation of magnetic fields due to the Weibel instability (WI) have important implications for laboratory and astrophysical plasmas, and this has drawn significant interest recently. Since the WI can generate a large magnetic field from no initial field, the maximum magnitudes achieved can have significant consequences for a number of applications. Hence, an understanding of the detailed dynamics driving the nonlinear saturation of the WI is important. This work considers the nonlinear saturation of the WI when counter-streaming populations of initially unmagnetized electrons are perturbed by a magnetic field oriented perpendicular to the direction of streaming. Previousmore » works have found magnetic trapping to be important and connected electron skin depth spatial scales to the nonlinear saturation of the WI. The results presented in this work are consistent with these findings for a high-temperature case. However, using a high-order continuum kinetic simulation tool, this work demonstrates that when the electron populations are colder, a significant electrostatic potential develops that works with the magnetic field to create potential wells. The electrostatic field develops due to transverse flows induced by the WI and in some cases is strengthened by a secondary instability. This field plays a key role in saturation of the WI for colder populations. In conclusion, the role of the electrostatic potential in Weibel instability saturation has not been studied in detail previously.« less

Nonlinear saturation of the Weibel instability

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

Cagas, P.; Hakim, A.; Scales, W.

The growth and saturation of magnetic fields due to the Weibel instability (WI) have important implications for laboratory and astrophysical plasmas, and this has drawn significant interest recently. Since the WI can generate a large magnetic field from no initial field, the maximum magnitudes achieved can have significant consequences for a number of applications. Hence, an understanding of the detailed dynamics driving the nonlinear saturation of the WI is important. This work considers the nonlinear saturation of the WI when counter-streaming populations of initially unmagnetized electrons are perturbed by a magnetic field oriented perpendicular to the direction of streaming. Previousmore » works have found magnetic trapping to be important and connected electron skin depth spatial scales to the nonlinear saturation of the WI. The results presented in this work are consistent with these findings for a high-temperature case. However, using a high-order continuum kinetic simulation tool, this work demonstrates that when the electron populations are colder, a significant electrostatic potential develops that works with the magnetic field to create potential wells. The electrostatic field develops due to transverse flows induced by the WI and in some cases is strengthened by a secondary instability. This field plays a key role in saturation of the WI for colder populations. In conclusion, the role of the electrostatic potential in Weibel instability saturation has not been studied in detail previously.« less

The danger within: the role of genetic, behavioural and ecological factors in population persistence of colour polymorphic species.

PubMed

Bolton, Peri E; Rollins, Lee A; Griffith, Simon C

2015-06-01

Polymorphic species have been the focus of important work in evolutionary biology. It has been suggested that colour polymorphic species have specific evolutionary and population dynamics that enable them to persist through environmental changes better than less variable species. We suggest that recent empirical and theoretical work indicates that polymorphic species may be more vulnerable to extinction than previously thought. This vulnerability arises because these species often have a number of correlated sexual, behavioural, life history and ecological traits, which can have a simple genetic underpinning. When exacerbated by environmental change, these alternate strategies can lead to conflict between morphs at the genomic and population levels, which can directly or indirectly affect population and evolutionary dynamics. In this perspective, we identify a number of ways in which the nature of the correlated traits, their underpinning genetic architecture, and the inevitable interactions between colour morphs can result in a reduction in population fitness. The principles illustrated here apply to all kinds of discrete polymorphism (e.g. behavioural syndromes), but we focus primarily on colour polymorphism because they are well studied. We urge further empirical investigation of the genetic architecture and interactions in polymorphic species to elucidate the impact on population fitness. © 2015 John Wiley & Sons Ltd.

Bayesian population analysis of a washin-washout physiologically based pharmacokinetic model for acetone

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

Moerk, Anna-Karin, E-mail: anna-karin.mork@ki.s; Jonsson, Fredrik; Pharsight, a Certara company, St. Louis, MO

2009-11-01

The aim of this study was to derive improved estimates of population variability and uncertainty of physiologically based pharmacokinetic (PBPK) model parameters, especially of those related to the washin-washout behavior of polar volatile substances. This was done by optimizing a previously published washin-washout PBPK model for acetone in a Bayesian framework using Markov chain Monte Carlo simulation. The sensitivity of the model parameters was investigated by creating four different prior sets, where the uncertainty surrounding the population variability of the physiological model parameters was given values corresponding to coefficients of variation of 1%, 25%, 50%, and 100%, respectively. The PBPKmore » model was calibrated to toxicokinetic data from 2 previous studies where 18 volunteers were exposed to 250-550 ppm of acetone at various levels of workload. The updated PBPK model provided a good description of the concentrations in arterial, venous, and exhaled air. The precision of most of the model parameter estimates was improved. New information was particularly gained on the population distribution of the parameters governing the washin-washout effect. The results presented herein provide a good starting point to estimate the target dose of acetone in the working and general populations for risk assessment purposes.« less

Bayesian modeling to assess populated areas impacted by radiation from Fukushima

NASA Astrophysics Data System (ADS)

Hultquist, C.; Cervone, G.

2017-12-01

Citizen-led movements producing spatio-temporal big data are increasingly important sources of information about populations that are impacted by natural disasters. Citizen science can be used to fill gaps in disaster monitoring data, in addition to inferring human exposure and vulnerability to extreme environmental impacts. As a response to the 2011 release of radiation from Fukushima, Japan, the Safecast project began collecting open radiation data which grew to be a global dataset of over 70 million measurements to date. This dataset is spatially distributed primarily where humans are located and demonstrates abnormal patterns of population movements as a result of the disaster. Previous work has demonstrated that Safecast is highly correlated in comparison to government radiation observations. However, there is still a scientific need to understand the geostatistical variability of Safecast data and to assess how reliable the data are over space and time. The Bayesian hierarchical approach can be used to model the spatial distribution of datasets and flexibly integrate new flows of data without losing previous information. This enables an understanding of uncertainty in the spatio-temporal data to inform decision makers on areas of high levels of radiation where populations are located. Citizen science data can be scientifically evaluated and used as a critical source of information about populations that are impacted by a disaster.

Annotated genetic linkage maps of Pinus pinaster Ait. from a Central Spain population using microsatellite and gene based markers.

PubMed

de Miguel, Marina; de Maria, Nuria; Guevara, M Angeles; Diaz, Luis; Sáez-Laguna, Enrique; Sánchez-Gómez, David; Chancerel, Emilie; Aranda, Ismael; Collada, Carmen; Plomion, Christophe; Cabezas, José-Antonio; Cervera, María-Teresa

2012-10-04

Pinus pinaster Ait. is a major resin producing species in Spain. Genetic linkage mapping can facilitate marker-assisted selection (MAS) through the identification of Quantitative Trait Loci and selection of allelic variants of interest in breeding populations. In this study, we report annotated genetic linkage maps for two individuals (C14 and C15) belonging to a breeding program aiming to increase resin production. We use different types of DNA markers, including last-generation molecular markers. We obtained 13 and 14 linkage groups for C14 and C15 maps, respectively. A total of 211 and 215 markers were positioned on each map and estimated genome length was between 1,870 and 2,166 cM respectively, which represents near 65% of genome coverage. Comparative mapping with previously developed genetic linkage maps for P. pinaster based on about 60 common markers enabled aligning linkage groups to this reference map. The comparison of our annotated linkage maps and linkage maps reporting QTL information revealed 11 annotated SNPs in candidate genes that co-localized with previously reported QTLs for wood properties and water use efficiency. This study provides genetic linkage maps from a Spanish population that shows high levels of genetic divergence with French populations from which segregating progenies have been previously mapped. These genetic maps will be of interest to construct a reliable consensus linkage map for the species. The importance of developing functional genetic linkage maps is highlighted, especially when working with breeding populations for its future application in MAS for traits of interest.

Annotated genetic linkage maps of Pinus pinaster Ait. from a Central Spain population using microsatellite and gene based markers

PubMed Central

2012-01-01

Background Pinus pinaster Ait. is a major resin producing species in Spain. Genetic linkage mapping can facilitate marker-assisted selection (MAS) through the identification of Quantitative Trait Loci and selection of allelic variants of interest in breeding populations. In this study, we report annotated genetic linkage maps for two individuals (C14 and C15) belonging to a breeding program aiming to increase resin production. We use different types of DNA markers, including last-generation molecular markers. Results We obtained 13 and 14 linkage groups for C14 and C15 maps, respectively. A total of 211 and 215 markers were positioned on each map and estimated genome length was between 1,870 and 2,166 cM respectively, which represents near 65% of genome coverage. Comparative mapping with previously developed genetic linkage maps for P. pinaster based on about 60 common markers enabled aligning linkage groups to this reference map. The comparison of our annotated linkage maps and linkage maps reporting QTL information revealed 11 annotated SNPs in candidate genes that co-localized with previously reported QTLs for wood properties and water use efficiency. Conclusions This study provides genetic linkage maps from a Spanish population that shows high levels of genetic divergence with French populations from which segregating progenies have been previously mapped. These genetic maps will be of interest to construct a reliable consensus linkage map for the species. The importance of developing functional genetic linkage maps is highlighted, especially when working with breeding populations for its future application in MAS for traits of interest. PMID:23036012

Improving cerebellar segmentation with statistical fusion

NASA Astrophysics Data System (ADS)

Plassard, Andrew J.; Yang, Zhen; Prince, Jerry L.; Claassen, Daniel O.; Landman, Bennett A.

2016-03-01

The cerebellum is a somatotopically organized central component of the central nervous system well known to be involved with motor coordination and increasingly recognized roles in cognition and planning. Recent work in multiatlas labeling has created methods that offer the potential for fully automated 3-D parcellation of the cerebellar lobules and vermis (which are organizationally equivalent to cortical gray matter areas). This work explores the trade offs of using different statistical fusion techniques and post hoc optimizations in two datasets with distinct imaging protocols. We offer a novel fusion technique by extending the ideas of the Selective and Iterative Method for Performance Level Estimation (SIMPLE) to a patch-based performance model. We demonstrate the effectiveness of our algorithm, Non- Local SIMPLE, for segmentation of a mixed population of healthy subjects and patients with severe cerebellar anatomy. Under the first imaging protocol, we show that Non-Local SIMPLE outperforms previous gold-standard segmentation techniques. In the second imaging protocol, we show that Non-Local SIMPLE outperforms previous gold standard techniques but is outperformed by a non-locally weighted vote with the deeper population of atlases available. This work advances the state of the art in open source cerebellar segmentation algorithms and offers the opportunity for routinely including cerebellar segmentation in magnetic resonance imaging studies that acquire whole brain T1-weighted volumes with approximately 1 mm isotropic resolution.

Older People and Poverty in Rural Britain: Material Hardships, Cultural Denials and Social Inclusions

ERIC Educational Resources Information Center

Milbourne, Paul; Doheny, Shane

2012-01-01

This paper explores the relations between older people, poverty and place in rural Britain. It develops previous work on rural poverty that has pointed both to the significance of older people within the rural poor population and to their denials of poverty. The paper also connects with recent discussions on the complexity of relations between…

Exploring the crowding-satisfaction relationship between day and overnight users in the lower Colorado River Basin, Texas

Treesearch

Yung-Ping Tseng; Gerard T. Kyle; C. Scott Shafer; Alan R. Graefe; Timothy A. Bradle

2009-01-01

As the boating population and number of boats in use have grown in the United States, boaters' perceptions of density at recreation sites and the associated impacts on their experience (e.g., satisfaction) are becoming increasingly important. This paper explores a recreational boating crowding-satisfaction model derived from previous work using safety and...

When study participants are vulnerable: getting and keeping the right team.

PubMed

Hill, Nikki L; Mogle, Jacqueline; Wion, Rachel; Kolanowski, Ann M; Fick, Donna; Behrens, Liza; Muhall, Paula; McDowell, Jane

2017-09-19

Research assistants (RAs) are critical members of all research teams. When a study involves vulnerable populations, it is particularly important to have the right team members. To describe the motivations, personal characteristics and team characteristics that promoted the job satisfaction of RAs who worked on two multi-year, randomised clinical trials involving older adults with dementia. A survey was conducted with 41 community members who worked as RAs for up to five years. Measures included demographics, work engagement, personality and characteristics of effective teams, as well as open-ended questions about respondents' experiences of the study. Quantitative analyses and coding of open-ended responses were used to summarise results. Almost all the RAs surveyed joined the team because of previous experiences of interacting with cognitively impaired older people. The RA respondents scored higher in 'dedication to work', 'extraversion', 'agreeableness' and 'conscientiousness' than average. An important aspect of their job satisfaction was team culture, including positive interpersonal interaction and the development of supportive team relationships. A positive work culture provides RAs with an opportunity to work with a study population that they are personally driven to help, and promotes motivation and satisfaction in team members. Results from this study can guide the recruitment, screening and retention of team members for studies that include vulnerable populations. ©2012 RCN Publishing Company Ltd. All rights reserved. Not to be copied, transmitted or recorded in any way, in whole or part, without prior permission of the publishers.

Disparities in Insurance Coverage, Health Services Use, and Access Following Implementation of the Affordable Care Act: A Comparison of Disabled and Nondisabled Working-Age Adults

PubMed Central

Kennedy, Jae; Wood, Elizabeth Geneva; Frieden, Lex

2017-01-01

The objective of this study was to assess trends in health insurance coverage, health service utilization, and health care access among working-age adults with and without disabilities before and after full implementation of the Affordable Care Act (ACA), and to identify current disability-based disparities following full implementation of the ACA. The ACA was expected to have a disproportionate impact on working-age adults with disabilities, because of their high health care usage as well as their previously limited insurance options. However, most published research on this population does not systematically look at effects before and after full implementation of the ACA. As the US Congress considers new health policy reforms, current and accurate data on this vulnerable population are essential. Weighted estimates, trend analyses and analytic models were conducted using the 1998-2016 National Health Interview Surveys (NHIS) and the 2014 Medical Expenditure Panel Survey. Compared with working-age adults without disabilities, those with disabilities are less likely to work, more likely to earn below the federal poverty level, and more likely to use public insurance. Average health costs for this population are 3 to 7 times higher, and access problems are far more common. Repeal of key features of the ACA, like Medicaid expansion and marketplace subsidies, would likely diminish health care access for working-age adults with disabilities. PMID:29166812

Registered nurses' perceptions of their professional work in nursing homes and home-based care: a focus group study.

PubMed

Carlson, Elisabeth; Rämgård, Margareta; Bolmsjö, Ingrid; Bengtsson, Mariette

2014-05-01

In Sweden, as well as in most industrialised countries, an increasing older population is expected to create a growing demand for health care staff. Previous studies have pointed to lack of proficient medical and nursing staff specialised in geriatric care, which poses serious threats to the care of a vulnerable population. At the same time, there are studies describing elderly care as a low-status career choice, attracting neither nurses nor student nurses. Judging from previous research it was deemed important to explore how nurses in elderly care perceive their work, thus possibly provide vital knowledge that can guide nurse educators and unit managers as a means to promote a career in elderly care. The aim of the present study was to illuminate how nurses, working in nursing homes and home-based care, perceived their professional work. This was a qualitative study using focus groups. 30 registered nurses in seven focus groups were interviewed. The participants worked in nursing homes and home-based care for the elderly in rural areas and in a larger city in southern Sweden. The interviews were analysed in line with the tradition of naturalistic inquiry. Our findings illustrate how nurses working in elderly care perceived their professional work as holistic and respectful nursing. Three categories of professional work emerged during analysis: (1) establishing long-term relationships, (2) nursing beyond technical skills, and (3) balancing independence and a sense of loneliness. The findings are important as they represent positive alternatives to the somewhat prevailing view on elderly care as depressing and undemanding. Nurse educators might use the key aspects as good examples, thus influencing student nurses' attitudes towards elderly care in a positive way. Elderly care agencies might find them helpful when recruiting and retaining nurses to a much needed area. Copyright © 2013 Elsevier Ltd. All rights reserved.

Genotoxic effect of exposure to metal(loid)s. A molecular epidemiology survey of populations living and working in Panasqueira mine area, Portugal.

PubMed

Coelho, Patrícia; García-Lestón, Julia; Costa, Solange; Costa, Carla; Silva, Susana; Dall'Armi, Valentina; Zoffoli, Roberto; Bonassi, Stefano; de Lima, João Pereira; Gaspar, Jorge Francisco; Pásaro, Eduardo; Laffon, Blanca; Teixeira, João Paulo

2013-10-01

Previous studies investigating the exposure to metal(loid)s of populations living in the Panasqueira mine area of central Portugal found a higher internal dose of elements such as arsenic, chromium, lead, manganese, molybdenum and zinc in exposed individuals. The aims of the present study were to evaluate the extent of genotoxic damage caused by environmental and occupational exposure in individuals previously tested for metal(loid) levels in different biological matrices, and the possible modulating role of genetic polymorphisms involved in metabolism and DNA repair. T-cell receptor mutation assay, comet assay, micronucleus (MN) test and chromosomal aberrations (CA) were performed in a group of 122 subjects working in the Panasqueira mine or living in the same region. The modifying effect of polymorphisms in GSTA2, GSTM1, GSTP1, GSTT1, XRCC1, APEX1, MPG, MUTYH, OGG1, PARP1, PARP4, ERCC1, ERCC4, and ERCC5 genes was investigated. Significant increases in the frequency of all biomarkers investigated were found in exposed groups, however those environmentally exposed were generally higher. Significant influences of polymorphisms were observed for GSTM1 deletion and OGG1 rs1052133 on CA frequencies, APEX1 rs1130409 on DNA damage, ERCC1 rs3212986 on DNA damage and CA frequency, and ERCC4 rs1800067 on MN and CA frequencies. Our results show that the metal(loid) contamination in the Panasqueira mine area induced genotoxic damage both in individuals working in the mine or living in the area. The observed effects are closely associated to the internal exposure dose, and are more evident in susceptible genotypes. The urgent intervention of authorities is required to protect exposed populations. © 2013.

Smoking and (Not) Voting: The Negative Relationship Between a Health-Risk Behavior and Political Participation in Colorado.

PubMed

Albright, Karen; Hood, Nancy; Ma, Ming; Levinson, Arnold H

2016-03-01

Considerable evidence suggests that cigarette smokers are an increasingly marginalized population, involved in fewer organizations and activities and with less interpersonal trust than their nonsmoking counterparts. However, only two previous studies, both among Swedish populations, have investigated smokers' attitudes toward political systems and institutions. The current, cross-sectional study examines smoking in relation to voting, a direct behavioral measure of civic and political engagement that at least partly reflects trust in formal political institutions. Secondary analyses were conducted of interview data from 11 626 respondents in the Colorado Tobacco Attitudes and Behaviors Survey. Data were collected via telephone between October 2005 and mid-April 2006 and included respondents' reported voting behavior in the 2004 national election; the participation rate was 89.7%. Balanced multiple logistic regression was used to examine associations between smoking and voting while controlling for other covariates known to be associated with both variables. In the final model, daily smokers were less than half as likely as nonsmokers to report having voted in the election. The results suggest possible consonance with previous work linking smoking with political mistrust. Possible causal mechanisms are discussed. This study is the first to link a health-risk behavior with electoral participation, and provides initial evidence that smoking is negatively associated with political participation. Future research should investigate how public health might enhance tobacco control efforts by taking nonvoting behavior into consideration, or creatively combining smoking cessation interventions with voter registration and other civic engagement work, particularly among socioeconomically disadvantaged populations. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Evolution of resistance and progression to disease during clonal expansion of cancer.

PubMed

Durrett, Richard; Moseley, Stephen

2010-02-01

Inspired by previous work of Iwasa et al. (2006) and Haeno et al. (2007), we consider an exponentially growing population of cancerous cells that will evolve resistance to treatment after one mutation or display a disease phenotype after two or more mutations. We prove results about the distribution of the first time when k mutations have accumulated in some cell, and about the growth of the number of type-k cells. We show that our results can be used to derive the previous results about a tumor grown to a fixed size. Copyright 2009 Elsevier Inc. All rights reserved.

Deducing the multi-trader population driving a financial market

NASA Astrophysics Data System (ADS)

Gupta, Nachi; Hauser, Raphael; Johnson, Neil

2005-12-01

We have previously laid out a basic framework for predicting financial movements and pockets of predictability by tracking the distribution of a multi-trader population playing on an artificial financial market model. This work explores extensions to this basic framework. We allow for more intelligent agents with a richer strategy set, and we no longer constrain the distribution over these agents to a probability space. We then introduce a fusion scheme which accounts for multiple runs of randomly chosen sets of possible agent types. We also discuss a mechanism for bias removal on the estimates.

Population turnover and adaptation in heterogeneous environments

NASA Astrophysics Data System (ADS)

Campos, Paulo R. A.; de Oliveira, Viviane M.

2012-02-01

We study adaptive dynamics in a structured population model of asexual individuals which takes into account environmental heterogeneity among the subpopulations. The key purpose of the present work is to address how population turnovers, i.e. extinction events followed by recolonization, affect the rate of fixation of advantageous mutations. This model is a generalization of our previous model to address the interplay between environmental correlation and evolutionary forces on the adaptive process. The incorporation of population turnovers into the model enables us to make a direct correspondence between the model and host-parasite dynamics (epidemiological models). Strikingly, contrary to the intuitive and usual deleterious effect associated to extinction events, it is observed that population turnovers can in fact speed up adaptation as heterogeneity rises. On the other side, in nearly homogeneous population turnovers have a neutral effect on fixation rates, but a detrimental outcome is also achieved when extinction events become very common. In resume, population turnover outcomes on fixation rates of advantageous mutations are strongly influenced by the selective correlation among the subpopulations (demes).

Improved population estimates through the use of auxiliary information

USGS Publications Warehouse

Johnson, D.H.; Ralph, C.J.; Scott, J.M.

1981-01-01

When estimating the size of a population of birds, the investigator may have, in addition to an estimator based on a statistical sample, information on one of several auxiliary variables, such as: (1) estimates of the population made on previous occasions, (2) measures of habitat variables associated with the size of the population, and (3) estimates of the population sizes of other species that correlate with the species of interest. Although many studies have described the relationships between each of these kinds of data and the population size to be estimated, very little work has been done to improve the estimator by incorporating such auxiliary information. A statistical methodology termed 'empirical Bayes' seems to be appropriate to these situations. The potential that empirical Bayes methodology has for improved estimation of the population size of the Mallard (Anas platyrhynchos) is explored. In the example considered, three empirical Bayes estimators were found to reduce the error by one-fourth to one-half of that of the usual estimator.

Effects of theatrical smokes and fogs on respiratory health in the entertainment industry.

PubMed

Varughese, Sunil; Teschke, Kay; Brauer, Michael; Chow, Yat; van Netten, Chris; Kennedy, Susan M

2005-05-01

Theatrical fogs (glycol or mineral oil aerosols) are widely used in the entertainment industry to create special effects and make lighting visible. We studied 101 employees at 19 sites using fogs and measured personal fog exposures, across work shift lung function, and acute and chronic symptoms. Results were also compared to an external control population, studied previously. Chronic work-related wheezing and chest tightness were significantly associated with increased cumulative exposure to fogs (mineral oil and glycols) over the previous 2 years. Acute cough and dry throat were associated with acute exposure to glycol-based fogs; increased acute upper airway symptoms were associated with increased fog aerosol overall. Lung function was significantly lower among those working closest to the fog source. Mineral oil- and glycol-based fogs are associated with acute and chronic adverse effects on respiratory health among employees. Reducing exposure, through controls, substitution, and elimination where possible, is likely to reduce these effects. (c) 2005 Wiley-Liss, Inc.

Associations of fatigue to work-related stress, mental and physical health in an employed community sample.

PubMed

Rose, D M; Seidler, A; Nübling, M; Latza, U; Brähler, E; Klein, E M; Wiltink, J; Michal, M; Nickels, S; Wild, P S; König, J; Claus, M; Letzel, S; Beutel, M E

2017-05-05

While work-related fatigue has become an issue of concern among European employees, the relationship between fatigue, depression and work-related stressors is far from clear. The purposes of this study were (1) to determine the associations of fatigue with work-related stressors, severe medical disease, health behavior and depression in the working population and (2) to determine the unique impact of work-related stressors on fatigue. We used cross-sectional data of N = 7,930 working participants enrolled in the Gutenberg Health Study (GHS) from 2007 to 2012 filled out the Personal Burnout Scale (PBS) of the Copenhagen Psychosocial Questionnaire (COPSOQ), the PHQ-9, and a list of work-related stressors. A total of 27.5% reported increased fatigue, esp. women, younger persons with a lower social status and income, smokers, severely medically ill, previously and currently depressed participants. Fatigue was consistently associated with severe medical disease, health behavior and depression, which need to be taken into account as potential confounders when analyzing its relationship to work-related strains. Depression was consistently associated with work-related stressors. However, after statistically partialling out depression, fatigue was still significantly associated with work-related stress. Fatigue as an indicator of allostatic load is consistently associated with work-related stressors such as work overload after controlling for depression. The brief Personal Burn-out Scale is suitable for assessing work-related fatigue in the general population.

Factors associated with agricultural work performed by adolescents from an immigrant farm worker population (MICASA study).

PubMed

Hennessy-Burt, T E; Stoecklin-Marois, M T; McCurdy, S A; Schenker, M B

2013-07-01

While studies have looked at the relationship of adolescent employment with health outcomes and risk behaviors, few have focused on children of hired farm workers. These children face unique challenges affecting their health and work environment. Exploring the frequency and nature of agricultural work characteristics among adolescent children of Hispanic hired farm workers is important for assessing the potential risks they face. MICASA is a population-based study of settled immigrant Hispanic farm working families in Mendota, California. We selected a cross-sectional random sample of adolescents (ages 11 to 18). Interviews assessed work history, place of birth, and acculturation. 38% of participants were female and 62% were male; 55% were born in the U.S., 38% in Mexico, and 7% in El Salvador; and 49% worked for pay during the last year. Among those who worked, farm work was most frequently reported (73.5%). Among those who had done farm work, the mean age at initiation was 14 years, and they worked a mean of 4.3 weeks during the previous year. Hoeing, picking, and packing/sorting were the most common tasks. In models adjusted for age and sex, low-acculturated adolescents were more likely than moderately acculturated to have worked in the past 12 months, to start work younger than age 14 years, and to do farm work. Farm work is common among adolescents in this Hispanic agricultural community and is strongly associated with foreign birth and low acculturation.

Common mental disorders and subsequent work disability: a population-based Health 2000 Study.

PubMed

Ahola, Kirsi; Virtanen, Marianna; Honkonen, Teija; Isometsä, Erkki; Aromaa, Arpo; Lönnqvist, Jouko

2011-11-01

Work disability due to common mental disorders has increased in Western countries during the past decade. The contribution of depressive, anxiety, and alcohol use disorders to all disability pensions at the population level is not known. Epidemiological health data from the Finnish Health 2000 Study, gathered in 2000-2001, was linked to the national register on disability pensions granted due to the ICD-10 diagnoses up to December 2007. Mental health at baseline was assessed using the Composite International Diagnostic Interview (CIDI). Sociodemographic, clinical, and work-related factors, health behaviors, and treatment setting were used as covariates in the logistic regression analyses among the 3164 participants aged 30-58 years. Anxiety, depressive, and comorbid common mental disorders predicted disability pension when adjusted for sex and age. In the fully adjusted multivariate model, comorbid common mental disorders, as well as physical illnesses, age over 45 years, short education, high job strain, and previous long-term sickness absence predicted disability pension. The study population included persons aged 30 or over. Sub groups according to mental disorders were quite small which may have diminished statistical power in some sub groups. Baseline predictors were measured only once and the length of exposure could not be determined. The systems regarding financial compensation to employees differ between countries. Comorbid mental disorders pose a high risk for disability pension. Other independent predictors of work disability include socio-demographic, clinical, work-related, and treatment factors, but not health behavior. More attention should be paid to work-related factors in order to prevent chronic work disability. Copyright © 2011 Elsevier B.V. All rights reserved.

Prospective motion correction with volumetric navigators (vNavs) reduces the bias and variance in brain morphometry induced by subject motion.

PubMed

Tisdall, M Dylan; Reuter, Martin; Qureshi, Abid; Buckner, Randy L; Fischl, Bruce; van der Kouwe, André J W

2016-02-15

Recent work has demonstrated that subject motion produces systematic biases in the metrics computed by widely used morphometry software packages, even when the motion is too small to produce noticeable image artifacts. In the common situation where the control population exhibits different behaviors in the scanner when compared to the experimental population, these systematic measurement biases may produce significant confounds for between-group analyses, leading to erroneous conclusions about group differences. While previous work has shown that prospective motion correction can improve perceived image quality, here we demonstrate that, in healthy subjects performing a variety of directed motions, the use of the volumetric navigator (vNav) prospective motion correction system significantly reduces the motion-induced bias and variance in morphometry. Copyright © 2015 Elsevier Inc. All rights reserved.

Joint association of multimorbidity and work ability with risk of long-term sickness absence: a prospective cohort study with register follow-up.

PubMed

Sundstrup, Emil; Jakobsen, Markus Due; Mortensen, Ole Steen; Andersen, Lars Louis

2017-03-01

Objectives The aim of this study was to determine the joint association of multimorbidity and work ability with the risk of long-term sickness absence (LTSA) in the general working population. Methods Cox regression analysis censoring for competing events (statutory retirement, early retirement, disability pension, immigration, or death) was performed to estimate the joint association of chronic diseases and work ability in relation to physical and mental demands of the job with the prospective risk for LTSA (defined as ≥6 consecutive weeks during 2-year follow-up) among 10 427 wage earners from the general working population (2010 Danish Work Environment Cohort Study). Control variables were age, gender, psychosocial work environment, smoking, leisure physical activity, body mass index, job group, and previous LTSA. Results Of the 10 427 respondents, 56.8% had experienced ≥1 chronic disease at baseline. The fully adjusted model showed an association between number of chronic diseases and risk of LTSA. This association was stronger among employees with poor work ability (either physical or mental). Compared to employees with no diseases and good physical work ability, the risk estimate for LTSA was 1.95 [95% confidence interval (95% CI) 1.50-2.52] for employees with ≥3 chronic diseases and good physical work ability, whereas it was 3.60 (95% CI 2.50-5.19) for those with ≥3 chronic diseases and poor physical work ability. Overall, the joint association of chronic disease and work ability with LTSA appears to be additive. Conclusions Poor work ability combined with ≥1 chronic diseases is associated with high risk of long-term sickness absence in the general working population. Initiatives to improve or maintain work ability should be highly prioritized to secure sustainable employability among workers with ≥1 chronic diseases.

Chronic pain, work performance and litigation.

PubMed

Blyth, Fiona M; March, Lyn M; Nicholas, Michael K; Cousins, Michael J

2003-05-01

The overall population impact of chronic pain on work performance has been underestimated as it has often been described in terms of work-related absence, excluding more subtle effects that chronic pain may have on the ability to work effectively. Additionally, most studies have focussed on occupational and/or patient cohorts and treatment seeking, rather than sampling from the general population. We undertook a population-based random digit dialling computer-assisted telephone survey with participants randomly selected within households in order to measure the impact of chronic pain on work performance. In addition, we measured the association between pain-related disability and litigation. The study took place in Northern Sydney Health Area, a geographically defined urban area of New South Wales, Australia, and included 484 adults aged 18 or over with chronic pain. The response rate was 73.4%. Working with pain was more common (on an average 83.8 days in 6 months) than lost work days due to pain (4.5 days) among chronic pain participants in full-time or part-time employment. When both lost work days and reduced-effectiveness work days were summed, an average of 16.4 lost work day equivalents occurred in a 6-month period, approximately three times the average number of lost work days. In multiple logistic regression modelling with pain-related disability as the dependent variable, past or present pain-related litigation had the strongest association (odds ratio (OR)=3.59, P=0.001). In conclusion, chronic pain had a larger impact on work performance than has previously been recognised, related to reduced performance while working with pain. A significant proportion were able to work effectively with pain, suggesting that complete relief of pain may not be an essential therapeutic target. Litigation (principally work-related) for chronic pain was strongly associated with higher levels of pain-related disability, even after taking into account other factors associated with poor functional outcomes.

Association between prematurity and the evolution of psychotic disorders in 22q11.2 deletion syndrome.

PubMed

Midbari Kufert, Yael; Nachmani, Ariela; Nativ, Einat; Weizman, Abraham; Gothelf, Doron

2016-12-01

In this study, we report the developmental, physical and psychiatric manifestations of 22q11.2 deletion syndrome (22q11.2DS) in a large Israeli cohort, and search for a possible association between preterm birth and the risk for psychotic disorders. The study population consisted of 128 individuals with 22q11.2DS (77 male, 51 female), aged 1-55 years (mean ± SD 12.9 ± 11.0). All subjects underwent a comprehensive medical evaluation. All subjects older than 5 years (n = 104) were also evaluated psychiatrically. Overall, we found rates of physical manifestations similar to those previously reported in the literature. Psychiatric disorders were very common among our study population, with psychotic disorders occurring in 16.3 % of the psychiatrically evaluated population. We found an association between the presence of psychotic disorders and preterm birth. Our results replicate and extend the findings of a previous work and suggest that the evolution of psychosis in 22q11.2DS is a neurodevelopmental process with early obstetric and medical precursors.

Work and excessive sleepiness among Brazilian evening high school students: effects on days off.

PubMed

Teixeira, Liliane; Lowden, Arne; Moreno, Claudia Roberta; Turte, Samantha; Nagai, Roberta; Latorre, Maria Do Rosário; Valente, Daniel; Fischer, Frida Marina

2010-01-01

Previous studies have revealed that students who work and study build up sleep deficits during the workweek, which can trigger a sleep rebound during days off. The objective of this study was to investigate the impact of working/non-working on sleepiness during days off among high school students. The study population, aged 14-21 years, attended evening classes in São Paulo, Brazil. For the study, the students completed questionnaires on living conditions, health, and work; wore actigraphs; and completed the Karolinska Sleepiness Scale (KSS). To predict sleepiness, a logistic regression analysis was performed. Excessive sleepiness was observed on the first day off among working students. Results suggest that working is a significant predictor for sleepiness and that two shifts of daily systematic activities, study and work, might lead to excessive daytime sleepiness on the first day off. Further, this observed excessive sleepiness may reflect the sleep debt accumulated during the workweek.

A modelling approach to vaccination and contraception programmes for rabies control in fox populations.

PubMed Central

Suppo, C; Naulin, J M; Langlais, M; Artois, M

2000-01-01

In a previous study, three of the authors designed a one-dimensional model to simulate the propagation of rabies within a growing fox population; the influence of various parameters on the epidemic model was studied, including oral-vaccination programmes. In this work, a two-dimensional model of a fox population having either an exponential or a logistic growth pattern was considered. Using numerical simulations, the efficiencies of two prophylactic methods (fox contraception and vaccination against rabies) were assessed, used either separately or jointly. It was concluded that far lower rates of administration are necessary to eradicate rabies, and that the undesirable side-effects of each programme disappear, when both are used together. PMID:11007334

Coherent population transfer in multilevel systems with magnetic sublevels. II. Algebraic analysis

NASA Astrophysics Data System (ADS)

Martin, J.; Shore, B. W.; Bergmann, K.

1995-07-01

We extend previous theoretical work on coherent population transfer by stimulated Raman adiabatic passage for states involving nonzero angular momentum. The pump and Stokes fields are either copropagating or counterpropagating with the corresponding linearly polarized electric-field vectors lying in a common plane with the magnetic-field direction. Zeeman splitting lifts the magnetic sublevel degeneracy. We present an algebraic analysis of dressed-state properties to explain the behavior noted in numerical studies. In particular, we discuss conditions which are likely to lead to a failure of complete population transfer. The applied strategy, based on simple methods of linear algebra, will also be successful for other types of discrete multilevel systems, provided the rotating-wave and adiabatic approximation are valid.

Long-term follow-up mortality study of petroleum refinery and chemical plant employees.

PubMed

Tsai, S P; Gilstrap, E L; Cowles, S R; Snyder, P J; Ross, C E

1996-01-01

A previous report presented the 1948-1983 mortality patterns of the Shell Deer Park Manufacturing Complex employees who were employed for at least 3 months from 1948 through 1972. The present study updates the earlier investigation by extending the vital status follow-up through 1989 and by expanding the cohort to include employees hired after 1972. As in the previous study, the overall mortality and cancer mortality for both refinery and chemical employees were quite favorable compared to residents in the local population. Among refinery workers, cancers for which a suspicion of work-relatedness was raised in the previous study, i.e. leukemia and cancers of the central nervous system and biliary passage/liver, no supportive evidence was found in this update. For both refinery and chemical plant employees, the mortality rate due to cancers of all lymphopoietic tissue increased with increasing duration of employment; this finding was also noted by the original study. This was also evident for lymphoreticulosarcoma in refinery employees and for leukemia in chemical plant employees. However, elevations of cancers of all lymphatic and hematopoietic tissue are primarily confined to employees who started work at the complex before 1946. By contrast, deaths from cancer of all lymphatic and hematopoietic tissue for employees hired after 1945 were 22% lower than the comparison population. Seven deaths with mesothelioma mentioned on the death certificates were identified, with 3.2 deaths expected, resulting in a statistically nonsignificant SMR of 219.

Public Education Finance Systems in the United States and Funding Policies for Populations with Special Educational Needs

ERIC Educational Resources Information Center

Verstegen, Deborah A.

2011-01-01

This research investigates state finance policies for public education using survey methodology. The purpose is to update previous work and the existing knowledge base in the field as well as to provide a compendium of finance and policy options that are used across the states to finance public elementary and secondary schools. Chief state school…

Fine mapping of a quantitative resistance gene for gray leaf spot of maize (Zea mays L.) derived from teosinte (Z. mays ssp. parviglumis)

USDA-ARS?s Scientific Manuscript database

In previous work, using near isogenic line (NIL) populations in which segments of the tesosinte (Zea mays ssp. parviglumis) genome had been introgressed into the background of the maize line B73, we had identified a QTL on chromosome 8, here called Qgls8, for gray leaf spot resistance. We identified...

Phylogenetic evaluation of Geomyces and allies reveals no close relatives of Pseudogymnoascus destructans, comb nov, in bat hibernacula of eastern North America

Treesearch

Andrew M. Minnis; Daniel L. Lindner

2013-01-01

White-nose syndrome (WNS) of bats, caused by the fungus previously known as Geomyces destructans, has decimated populations of insectivorous bats in eastern North America. Recent work on fungi associated with bat hibernacula uncovered a large number of species of Geomyces and allies, far exceeding the number of described species....

Pyramiding Sclerotinia head rot and stalk rot resistances into elite sunflower breeding lines with the aid of DNA markers

USDA-ARS?s Scientific Manuscript database

Work was conducted in 2008 to determine the stalk rot resistance of RILs from the RHA 280 x RHA 801 population, as well as to begin introgression of previously identified QTL for head rot resistance into elite sunflower germplasm lines. The stalk rot RILs and their testcrosses with cms HA 89 were t...

Profile of Home Care Aides, Nursing Home Aides, and Hospital Aides: Historical Changes and Data Recommendations

ERIC Educational Resources Information Center

Yamada, Yoshiko

2002-01-01

Purpose: To examine demographic characteristics and work conditions of home care aides, nursing home aides, and hospital aides in the late 1980s and late 1990s. Design and Methods: This study replicated a previous study which examined the Current Population Survey (CPS) March supplement from 1987 to 1989. The present study examined CPS data from…

A rare functional cardioprotective APOC3 variant has risen in frequency in distinct population isolates

PubMed Central

Tachmazidou, Ioanna; Dedoussis, George; Southam, Lorraine; Farmaki, Aliki-Eleni; Ritchie, Graham R. S.; Xifara, Dionysia K.; Matchan, Angela; Hatzikotoulas, Konstantinos; Rayner, Nigel W.; Chen, Yuan; Pollin, Toni I.; O’Connell, Jeffrey R.; Yerges-Armstrong, Laura M.; Kiagiadaki, Chrysoula; Panoutsopoulou, Kalliope; Schwartzentruber, Jeremy; Moutsianas, Loukas; Tsafantakis, Emmanouil; Tyler-Smith, Chris; McVean, Gil; Xue, Yali; Zeggini, Eleftheria

2013-01-01

Isolated populations can empower the identification of rare variation associated with complex traits through next generation association studies, but the generalizability of such findings remains unknown. Here we genotype 1,267 individuals from a Greek population isolate on the Illumina HumanExome Beadchip, in search of functional coding variants associated with lipids traits. We find genome-wide significant evidence for association between R19X, a functional variant in APOC3, with increased high-density lipoprotein and decreased triglycerides levels. Approximately 3.8% of individuals are heterozygous for this cardioprotective variant, which was previously thought to be private to the Amish founder population. R19X is rare (<0.05% frequency) in outbred European populations. The increased frequency of R19X enables discovery of this lipid traits signal at genome-wide significance in a small sample size. This work exemplifies the value of isolated populations in successfully detecting transferable rare variant associations of high medical relevance. PMID:24343240

A rare functional cardioprotective APOC3 variant has risen in frequency in distinct population isolates.

PubMed

Tachmazidou, Ioanna; Dedoussis, George; Southam, Lorraine; Farmaki, Aliki-Eleni; Ritchie, Graham R S; Xifara, Dionysia K; Matchan, Angela; Hatzikotoulas, Konstantinos; Rayner, Nigel W; Chen, Yuan; Pollin, Toni I; O'Connell, Jeffrey R; Yerges-Armstrong, Laura M; Kiagiadaki, Chrysoula; Panoutsopoulou, Kalliope; Schwartzentruber, Jeremy; Moutsianas, Loukas; Tsafantakis, Emmanouil; Tyler-Smith, Chris; McVean, Gil; Xue, Yali; Zeggini, Eleftheria

2013-01-01

Isolated populations can empower the identification of rare variation associated with complex traits through next generation association studies, but the generalizability of such findings remains unknown. Here we genotype 1,267 individuals from a Greek population isolate on the Illumina HumanExome Beadchip, in search of functional coding variants associated with lipids traits. We find genome-wide significant evidence for association between R19X, a functional variant in APOC3, with increased high-density lipoprotein and decreased triglycerides levels. Approximately 3.8% of individuals are heterozygous for this cardioprotective variant, which was previously thought to be private to the Amish founder population. R19X is rare (<0.05% frequency) in outbred European populations. The increased frequency of R19X enables discovery of this lipid traits signal at genome-wide significance in a small sample size. This work exemplifies the value of isolated populations in successfully detecting transferable rare variant associations of high medical relevance.

Decreased Photosystem II Core Phosphorylation in a Yellow-Green Mutant of Wheat Showing Monophasic Fluorescence Induction Curve.

PubMed Central

Giardi, M. T.; Kucera, T.; Briantais, J. M.; Hodges, M.

1995-01-01

In the present work we study the regulation of the distribution of the phosphorylated photosystem II (PSII) core populations present in grana regions of the thylakoids from several plant species. The heterogeneous nature of PSII core phosphorylation has previously been reported (M.T. Giardi, F. Rigoni, R. Barbato [1992] Plant Physiol 100: 1948-1954; M.T. Giardi [1993] Planta 190: 107-113). The pattern of four phosphorylated PSII core populations in the grana regions appears to be ubiquitous in higher plants. In the dark, at least two phosphorylated PSII core populations are always detected. A mutant of wheat (Triticum durum) that shows monophasic room-temperature photoreduction of the primary quinone electron acceptor of PSII as measured by chlorophyll fluorescence increase in the presence and absence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea and by fluorescence upon flash illumination in intact leaves also lacks the usual distribution of phosphorylated PSII core populations. In this mutant, the whole PSII core population pattern is changed, probably due to altered threonine kinase activity, which leads to the absence of light-induced phosphorylation of CP43 and D2 proteins. The results, correlated to previous experiments in vivo, support the idea that the functional heterogeneity observed by fluorescence is correlated in part to the PSII protein phosphorylation in the grana. PMID:12228652

Comparison of Campylobacter jejuni isolates from human, food, veterinary and environmental sources in Iceland using PFGE, MLST and fla-SVR sequencing.

PubMed

Magnússon, S H; Guðmundsdóttir, S; Reynisson, E; Rúnarsson, A R; Harðardóttir, H; Gunnarson, E; Georgsson, F; Reiersen, J; Marteinsson, V Th

2011-10-01

Campylobacter jejuni isolates from various sources in Iceland were genotyped with the aim of assessing the genetic diversity, population structure, source distribution and campylobacter transmission routes to humans. A collection of 584 Campylobacter isolates were collected from clinical cases, food, animals and environment in Iceland in 1999-2002, during a period of national Campylobacter epidemic in Iceland. All isolates were characterized by pulse field gel electrophoresis (PFGE), and selected subset of 52 isolates representing the diversity of the identified PFGE types was further genotyped using multilocus sequence typing (MLST) and fla-SVR sequencing to gain better insight into the population structure. The results show a substantial diversity within the Icelandic Campylobacter population. Majority of the human Campylobacter infections originated from domestic chicken and cattle isolates. MLST showed the isolates to be distributed among previously reported and common sequence type complexes in the MLST database. The genotyping of Campylobacter from various sources has not previously been reported from Iceland, and the results of the study gave a valuable insight into the population structure of Camp. jejuni in Iceland, source distribution and transmission routes to humans. The geographical isolation of Iceland in the north Atlantic provides new information on Campylobacter population dynamics on a global scale. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology No claim to Icelandic Government works.

Evaluation of questionnaire-based information on previous physical work loads. Stockholm MUSIC 1 Study Group. Musculoskeletal Intervention Center.

PubMed

Torgén, M; Winkel, J; Alfredsson, L; Kilbom, A

1999-06-01

The principal aim of the present study was to evaluate questionnaire-based information on past physical work loads (6-year recall). Effects of memory difficulties on reproducibility were evaluated for 82 subjects by comparing previously reported results on current work loads (test-retest procedure) with the same items recalled 6 years later. Validity was assessed by comparing self-reports in 1995, regarding work loads in 1989, with worksite measurements performed in 1989. Six-year reproducibility, calculated as weighted kappa coefficients (k(w)), varied between 0.36 and 0.86, with the highest values for proportion of the workday spent sitting and for perceived general exertion and the lowest values for trunk and neck flexion. The six-year reproducibility results were similar to previously reported test-retest results for these items; this finding indicates that memory difficulties was a minor problem. The validity of the questionnaire responses, expressed as rank correlations (r(s)) between the questionnaire responses and workplace measurements, varied between -0.16 and 0.78. The highest values were obtained for the items sitting and repetitive work, and the lowest and "unacceptable" values were for head rotation and neck flexion. Misclassification of exposure did not appear to be differential with regard to musculoskeletal symptom status, as judged by the calculated risk estimates. The validity of some of these self-administered questionnaire items appears sufficient for a crude assessment of physical work loads in the past in epidemiologic studies of the general population with predominantly low levels of exposure.

Long-term follow-up of disability pensioners having musculoskeletal disorders.

PubMed

Magnussen, Liv H; Strand, Liv I; Skouen, Jan S; Eriksen, Hege R

2009-11-10

Previously we have conducted a randomised controlled trial (RCT) to evaluate the effect of a brief cognitive behavioural program with a vocational approach aiming to return disability pensioners with back pain to work, as compared to no intervention. One year after the intervention, 10 participants (22%) who received the program and 5 (11%) in the control group reported to have entered a return to work process. The aims of this study were to evaluate long-term effects of the intervention, and compare this effect to 2 reference populations not participating in the original trial. Three groups of disability pensioners were investigated: 1) Disability pensioners having back pain (n = 89) previously participating in the RCT (randomized to either a brief cognitive behavioural intervention or to a control group), 2) 342 disability pensioners having back pain, but refusing to participate in the study and 3) 449 disability pensioners having other musculoskeletal disorders than back pain. Primary outcome was return to work, defined as a reduction in payment of disability pension. Only 2 of 89 (2.3%) participants from the RCT had reduced disability pension at 3-years follow-up, both from the control group. None of the participants that had been in a process of returning to work after 1 year had actually gained employment at 3-years follow-up. In the 2 groups not participating in the previous RCT, only 4 (1.2%) and 8 (1.6%) had returned to work after 3 years respectively. The number of pensioners who returned to work was negligible in all groups regardless of having participated in a cognitive behavioural intervention or not.

An emperor penguin population estimate: the first global, synoptic survey of a species from space.

PubMed

Fretwell, Peter T; Larue, Michelle A; Morin, Paul; Kooyman, Gerald L; Wienecke, Barbara; Ratcliffe, Norman; Fox, Adrian J; Fleming, Andrew H; Porter, Claire; Trathan, Phil N

2012-01-01

Our aim was to estimate the population of emperor penguins (Aptenodytes fosteri) using a single synoptic survey. We examined the whole continental coastline of Antarctica using a combination of medium resolution and Very High Resolution (VHR) satellite imagery to identify emperor penguin colony locations. Where colonies were identified, VHR imagery was obtained in the 2009 breeding season. The remotely-sensed images were then analysed using a supervised classification method to separate penguins from snow, shadow and guano. Actual counts of penguins from eleven ground truthing sites were used to convert these classified areas into numbers of penguins using a robust regression algorithm.We found four new colonies and confirmed the location of three previously suspected sites giving a total number of emperor penguin breeding colonies of 46. We estimated the breeding population of emperor penguins at each colony during 2009 and provide a population estimate of ~238,000 breeding pairs (compared with the last previously published count of 135,000-175,000 pairs). Based on published values of the relationship between breeders and non-breeders, this translates to a total population of ~595,000 adult birds.There is a growing consensus in the literature that global and regional emperor penguin populations will be affected by changing climate, a driver thought to be critical to their future survival. However, a complete understanding is severely limited by the lack of detailed knowledge about much of their ecology, and importantly a poor understanding of their total breeding population. To address the second of these issues, our work now provides a comprehensive estimate of the total breeding population that can be used in future population models and will provide a baseline for long-term research.

An Emperor Penguin Population Estimate: The First Global, Synoptic Survey of a Species from Space

PubMed Central

Fretwell, Peter T.; LaRue, Michelle A.; Morin, Paul; Kooyman, Gerald L.; Wienecke, Barbara; Ratcliffe, Norman; Fox, Adrian J.; Fleming, Andrew H.; Porter, Claire; Trathan, Phil N.

2012-01-01

Our aim was to estimate the population of emperor penguins (Aptenodytes fosteri) using a single synoptic survey. We examined the whole continental coastline of Antarctica using a combination of medium resolution and Very High Resolution (VHR) satellite imagery to identify emperor penguin colony locations. Where colonies were identified, VHR imagery was obtained in the 2009 breeding season. The remotely-sensed images were then analysed using a supervised classification method to separate penguins from snow, shadow and guano. Actual counts of penguins from eleven ground truthing sites were used to convert these classified areas into numbers of penguins using a robust regression algorithm. We found four new colonies and confirmed the location of three previously suspected sites giving a total number of emperor penguin breeding colonies of 46. We estimated the breeding population of emperor penguins at each colony during 2009 and provide a population estimate of ∼238,000 breeding pairs (compared with the last previously published count of 135,000–175,000 pairs). Based on published values of the relationship between breeders and non-breeders, this translates to a total population of ∼595,000 adult birds. There is a growing consensus in the literature that global and regional emperor penguin populations will be affected by changing climate, a driver thought to be critical to their future survival. However, a complete understanding is severely limited by the lack of detailed knowledge about much of their ecology, and importantly a poor understanding of their total breeding population. To address the second of these issues, our work now provides a comprehensive estimate of the total breeding population that can be used in future population models and will provide a baseline for long-term research. PMID:22514609

Decreasing population blood pressure is not mediated by changes in habitual physical activity. Results from 15 years of follow-up.

PubMed

Andersen, Ulla Overgaard; Jensen, Gorm

2007-01-01

Population blood pressure (PBP) is the average BP shared by all members of a population. In PBP research, the main focus is on the great majority of individuals who are healthy in respect to blood pressure. From previous studies, we know that PBP decreased 2 mmHg during 15 years of follow-up. This decrease leads to significant reductions in cardiovascular (CV) and cerebrovascular risk. The major aim of the present study was to evaluate the effect of habitual physical activity on PBP. Copenhagen City Heart Study is a longitudinal epidemiological study of CV risk in a random population sample. Three surveys were performed with 15 years of follow-up. BP was measured under standardized circumstances. A questionnaire concerning physical exercise was completed. Two scales were used, describing physical activity at work and during leisure-time, respectively. Most of the subjects belonged to the sedentary or low physical activity categories. The population did not change physical activity habits during the observation time. There was no significant difference in either systolic or diastolic BP between the categories. The previously observed reduction in PBP is not explained by a change in the population physical activity habits. This fact illustrates the difference between the high-risk strategy and the population strategy. In the first, the preventive strategy identifies hypertensive individuals and offers them antihypertensive medication and lifestyle modulation such as more and regular physical activity to improve blood pressure and lower individual CV and cerebrovascular risk. In contrast, the "population strategy" seeks to control the determinants of incidence in the population as a whole. This paper demonstrates that physical activity is not a determinant of PBP.

Multi-objective optimization in systematic conservation planning and the representation of genetic variability among populations.

PubMed

Schlottfeldt, S; Walter, M E M T; Carvalho, A C P L F; Soares, T N; Telles, M P C; Loyola, R D; Diniz-Filho, J A F

2015-06-18

Biodiversity crises have led scientists to develop strategies for achieving conservation goals. The underlying principle of these strategies lies in systematic conservation planning (SCP), in which there are at least 2 conflicting objectives, making it a good candidate for multi-objective optimization. Although SCP is typically applied at the species level (or hierarchically higher), it can be used at lower hierarchical levels, such as using alleles as basic units for analysis, for conservation genetics. Here, we propose a method of SCP using a multi-objective approach. We used non-dominated sorting genetic algorithm II in order to identify the smallest set of local populations of Dipteryx alata (baru) (a Brazilian Cerrado species) for conservation, representing the known genetic diversity and using allele frequency information associated with heterozygosity and Hardy-Weinberg equilibrium. We worked in 3 variations for the problem. First, we reproduced a previous experiment, but using a multi-objective approach. We found that the smallest set of populations needed to represent all alleles under study was 7, corroborating the results of the previous study, but with more distinct solutions. In the 2nd and 3rd variations, we performed simultaneous optimization of 4 and 5 objectives, respectively. We found similar but refined results for 7 populations, and a larger portfolio considering intra-specific diversity and persistence with populations ranging from 8-22. This is the first study to apply multi-objective algorithms to an SCP problem using alleles at the population level as basic units for analysis.

A century of transitions in New York City's measles dynamics.

PubMed

Hempel, Karsten; Earn, David J D

2015-05-06

Infectious diseases spreading in a human population occasionally exhibit sudden transitions in their qualitative dynamics. Previous work has successfully predicted such transitions in New York City's historical measles incidence using the seasonally forced susceptible-infectious-recovered (SIR) model. This work relied on a dataset spanning 45 years (1928-1973), which we have extended to 93 years (1891-1984). We identify additional dynamical transitions in the longer dataset and successfully explain them by analysing attractors and transients of the same mechanistic epidemiological model. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

[Neuroplasticity as a basis for early rehabilitation of stroke patients].

PubMed

Putilina, M V

2011-01-01

The review is devoted to the current state of the problem of early rehabilitation of stroke patients. The rate of primary disability in patients after stroke is 3.2 per 10000 population but only 20% of previously working patients return to work. Early rehabilitation is treatment actions during a period following stroke. Adequate treatment during this period may decrease the extent of brain damage and improve disease outcome. The complexity of rehabilitation consists in using several complementary pharmacological and non-pharmacological rehabilitation measures. Appearance of new techniques of rehabilitation treatment aimed at neuroplasticity stimulation increases treatment potential of rehabilitative technologies.

Reliability and validity of the Japanese version of the Work Limitations Questionnaire in employees of multiple private companies.

PubMed

Ida, Hiromasa; Nakagawa, Kazumi; Tanoue, Asuka; Nakamura, Kentarou; Okamura, Tatsuya

2017-01-31

Previous studies reported that presenteeism costs the enterprises more than absenteeism. It becomes more important for corporate management to evaluate the outcomes of health promotion initiatives for their employees using work performance scales in Japan. We previously developed a Japanese version of Work Limitations Questionnaire (WLQ-J), a presenteeism scale developed by Lerner D. et al., and conducted an internet survey to examine the reliability and validity of WLQ-J with 710 employees from an IT company and a medical institution as subjects and reported the study results (Ida et al, 2012). The objective of the present study is to examine the reliability and validity of WLQ-J with employees from more companies and industries than those included in the previous study. We analyzed for 4,440 employees from 14 companies and 9 industries as subjects, who were selected from a total of 4,712 employees who answered both WLQ-J and Brief Job Stress Questionnaire (BJSQ) on the internet or paper survey conducted from September 2014 to January 2015. The subjects' average age was 40.3±11.8 years (33.2±9.5 years in the previous study), with the percentage of males and females being 77.9% and 21.1%, respectively. The factor structure of WLQ-J accorded with that of the original version of WLQ. This supports the factorial validity of WLQ-J. In addition, sufficient internal consistency was recognized by Cronbach's alpha of the whole scale (0.87 for the present study and 0.97 for the previous study) and the subscales (0.77-0.94 for the present study and 0.88-0.95 for the previous study). The four subscale scores of WLQ-J were significantly correlated with the stress response of BJSQ with correlation coefficients of 0.28-0.64 for the present study and 0.39-0.60 for the previous study (p < 0.01 for both studies). Moreover, criterion-related validity of WLQ-J was also supported by the significant dose-response relationship between the subscale scores of WLQ-J and stress response of BJSQ (p < 0.01 for the previous study and p < 0.001 for the present study). The present study demonstrated the reliability and validity of WLQ-J in a population of employees from more companies and industries than those in the previous study, with its average age and percentage of males and females close to those of the whole Japanese industries. This suggests that WLQ-J is available as a stable scale for presenteeism in different populations in Japan.

Neutral theory, microbial practice: challenges in bacterial population genetics.

PubMed

Rocha, Eduardo P C

2018-04-19

Kimura's outstanding contributions to population genetics included many elegant theoretical results on the vagaries of alleles in populations. Once polymorphism data showed extensive variation in natural populations, these results led naturally to the Neutral Theory. In this article, I'll depart from some of these results to focus on four major open problems in microbial population genetics with direct implications to the study of molecular evolution: the lack of neutral polymorphism, the modeling of genetic exchanges, the population genetics of ill-defined populations, and the difficulty of untangling selection and demography in the light of the previous issues. Whilst studies in population genetics usually focus on single nucleotide polymorphism and allelic recombination, ignoring even small indels, a large fraction of genetic diversification in Bacteria results from horizontal gene transfer. Ignoring this fact defeats the purpose of population genetics: to characterize the genetic variation in populations and their adaptive effects. I'll argue that, following on Kimura's life work, one may need to develop new approaches to study microbes that reproduce asexually but are able to engage in gene exchanges with very distantly related organisms in a context where random sampling is often unachievable, populations are ill-defined, genetic linkage is strong, and random drift is rare.

Developing measures of food and nutrition security within an Australian context.

PubMed

Archer, Claire; Gallegos, Danielle; McKechnie, Rebecca

2017-10-01

To develop a measure of food and nutrition security for use among an Australian population that measures all pillars of food security and to establish its content validity. The study consisted of two phases. Phase 1 involved focus groups with experts working in the area of food security. Data were assessed using content analysis and results informed the development of a draft tool. Phase 2 consisted of a series of three online surveys using the Delphi technique. Findings from each survey were used to establish content validity and progressively modify the tool until consensus was reached for all items. Australia. Phase 1 focus groups involved twenty-five experts working in the field of food security, who were attending the Dietitians Association of Australia National Conference, 2013. Phase 2 included twenty-five experts working in food security, who were recruited via email. Findings from Phase 1 supported the need for an Australian-specific tool and highlighted the failure of current tools to measure across all pillars of food security. Participants encouraged the inclusion of items to measure barriers to food acquisition and the previous single item to enable comparisons with previous data. Phase 2 findings informed the selection and modification of items for inclusion in the final tool. The results led to the development of a draft tool to measure food and nutrition security, and supported its content validity. Further research is needed to validate the tool among the Australian population and to establish inter- and intra-rater reliability.

The Impact of an Aging Population in the Workplace.

PubMed

White, Mercedia Stevenson; Burns, Candace; Conlon, Helen Acree

2018-03-01

According to the Centers for Disease Control and Prevention, the number of people 65 years of age or older living in the United States is projected to double by 2030 to 72 million adults, representing 20% of the total U.S. Evidence suggests that older Americans are working longer and spending more time on the job than their peers did in previous years. The increased number of older adults working longer is observed not only in the Unites States but also worldwide. There are numerous ramifications associated with the changing demographics and the expanding prevalence of an aging population in the workforce. Dynamics that arise include stereotyping and discrimination, longevity and on-site expert knowledge, variances in workplace behavior, a multigenerational employee pool, chronic disease management, occupational safety, and the application of adaptive strategies to reduce injury occurrences. Occupational health nurses play a pivotal role in implementing best practices for an aging-friendly workplace.

Femoral Component Sizing in Oxford Unicompartmental Knee Replacement: Existing Guidelines Do Not Work for Indian Patients.

PubMed

Malhotra, Rajesh; Gaba, Sahil; Wahal, Naman; Kumar, Vijay; Srivastava, Deep N; Pandit, Hemant

2018-02-28

Oxford unicompartmental knee replacement (OUKR) has shown excellent long-term clinical outcomes as well as implant survival when used for correct indications with optimal surgical technique. Anteromedial osteoarthritis is highly prevalent in Indian patients, and OUKR is the ideal treatment option in such cases. Uncertainty prevails about the best method to determine femoral component size in OUKR. Preoperative templating has been shown to be inaccurate, while height- and gender-based guidelines based on European population might not apply to the Indian patients. Microplasty instrumentation introduced in 2012 introduced the sizing spoon, which has the dual function of femoral component sizing and determining the level of tibia cut. We aimed to check the accuracy of sizing spoon and also to determine whether the present guidelines are appropriate for use in the Indian patients. A total of 130 consecutive Oxford mobile bearing medial cemented UKR performed using the Microplasty instrumentation were included. The ideal femoral component size for each knee was recorded by looking for overhang and underhang in post-operative lateral knee radiograph. The accuracy of previous guidelines was determined by applying them to our study population. Previously published guidelines (which were based on Western population) proved to be accurate in only 37% of cases. Hence, based on the demographics of our study population, we formulated modified height- and gender-based guidelines, which would better suit the Indian population. Accuracy of modified guidelines was estimated to be 74%. The overall accuracy of sizing spoon (75%), when used as an intraoperative guide, was similar to that of modified guidelines. Existing guidelines for femoral component sizing do not work in Indian patients. Modified guidelines and use of intraoperative spoon should be used to choose the optimal implant size while performing OUKR in Indian patients. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

A Multi-color Optical Survey of the Orion Nebula Cluster. II. The H-R Diagram

NASA Astrophysics Data System (ADS)

Da Rio, N.; Robberto, M.; Soderblom, D. R.; Panagia, N.; Hillenbrand, L. A.; Palla, F.; Stassun, K. G.

2010-10-01

We present a new analysis of the stellar population of the Orion Nebula Cluster (ONC) based on multi-band optical photometry and spectroscopy. We study the color-color diagrams in BVI, plus a narrowband filter centered at 6200 Å, finding evidence that intrinsic color scales valid for main-sequence dwarfs are incompatible with the ONC in the M spectral-type range, while a better agreement is found employing intrinsic colors derived from synthetic photometry, constraining the surface gravity value as predicted by a pre-main-sequence isochrone. We refine these model colors even further, empirically, by comparison with a selected sample of ONC stars with no accretion and no extinction. We consider the stars with known spectral types from the literature, and extend this sample with the addition of 65 newly classified stars from slit spectroscopy and 182 M-type from narrowband photometry; in this way, we isolate a sample of about 1000 stars with known spectral type. We introduce a new method to self-consistently derive the stellar reddening and the optical excess due to accretion from the location of each star in the BVI color-color diagram. This enables us to accurately determine the extinction of the ONC members, together with an estimate of their accretion luminosities. We adopt a lower distance for the Orion Nebula than previously assumed, based on recent parallax measurements. With a careful choice of also the spectral-type-temperature transformation, we produce the new Hertzsprung-Russell diagram of the ONC population, more populated than previous works. With respect to previous works, we find higher luminosity for late-type stars and a slightly lower luminosity for early types. We determine the age distribution of the population, peaking from ~2 to ~3 Myr depending on the model. We study the distribution of the members in the mass-age plane and find that taking into account selection effects due to incompleteness, removes an apparent correlation between mass and age. We derive the initial mass function for low- and intermediate-mass members of the ONC, which turns out to be model dependent and shows a turnover at M <~ 0.2 M sun.

Incidence of carpal tunnel syndrome in the US military population.

PubMed

Wolf, Jennifer Moriatis; Mountcastle, Sally; Owens, Brett D

2009-09-01

Carpal tunnel syndrome (CTS) is a common disease. Its epidemiology has been evaluated previously, mostly in regional populations or in working groups, with an incidence between 1.5 and 3.5 per 1,000 person-years. We studied this diagnosis in the US military population, with the hypothesis that this young population would have a lower incidence of CTS than previously reported in general populations. The Defense Medical Epidemiology Database notes all medical encounters for all US military personnel and maintains the number of all personnel on active duty each year. We queried the database using the International Classification of Diseases, ninth revision, code 354.0 (CTS) and analyzed the personnel presenting for initial visits for the years 1998-2006. Multivariate Poisson analysis was performed, controlling for rank, gender, age, and race. The raw incidence of CTS in the US military was 3.98 per 1,000 person-years, in a population of 12,298,088 person-years. Females had a significantly higher incidence of CTS than males, with an adjusted incidence rate ratio of 3.29. CTS incidence increased by age, with the age group > or = 40 years having a significantly higher incidence. Additionally, military rank was found to be an independent risk factor for CTS, with rates higher in senior officer and enlisted groups. This suggests that occupational requirements have an effect on CTS within the military. We showed a comparable incidence of CTS between the US military and general population, with a significantly higher female cohort with a diagnosis of CTS. Increased age and advanced rank were risk factors for CTS.

Prevalence of Vitiligo and Associated Comorbidities in Korea

PubMed Central

Lee, Hemin; Lee, Mu-Hyoung; Lee, Dong Youn; Kang, Hee Young; Kim, Ki Ho; Choi, Gwang Seong; Shin, Jeonghyun; Lee, Hee Jung; Kim, Dong Hyun; Kim, Tae Heung; Lee, Ai-Young; Lee, Seung Chul; Lee, Sanghoon; Kim, Kyoung Wan; Hann, Seung-Kyung

2015-01-01

Purpose Vitiligo prevalence and its associated comorbidities rate have been reported variably among different populations. We aimed to determine the prevalence of vitiligo in Korea along with the baseline rate of comorbidities and compared the risks to the general population using hospital visit information of the total population in Korea. Materials and Methods We assessed demographic characteristics of vitiligo patients in Korean population from 2009 to 2011 in a nationwide data from Health Insurance Review Assessment Service. Patients who had at least one visit to Korea's primary, secondary, or tertiary referral hospitals with International Classification of Diseases, 10th Revision, Clinical Modification diagnosis code for vitiligo were identified. As a supplementary study, comorbidities associated with vitiligo were selected for further review to calculate relative risks compared to the general population. Results The annual prevalence of vitiligo determined by hospital-visiting rate in Korea was 0.12% to 0.13% over a three year period. In sync with other previous epidemiological studies, there was bimodal distribution among the age groups and no difference between genders. Also, vitiligo in Korean population was associated with various autoimmune/non-autoimmune diseases such as thyroiditis, atopic dermatitis, and psoriasis. Conclusion This study was by far the most comprehensive review on prevalence of vitiligo using a data of total population in Korea. The prevalence is within a range of those reported in previous literatures, and increased risk of comorbidities such as thyroid diseases and psoriasis in vitiligo might aid clinicians in the initial work up of vitiligo patients and concurrent follow ups. PMID:25837178

Prevalence of Autism in Children of Somali Origin Living in Stockholm: Brief Report of an At-Risk Population

ERIC Educational Resources Information Center

Barnevik-Olsson, Martina; Gillberg, Christopher; Fernell, Elisabeth

2010-01-01

This work was a follow-up study (birth years 1999-2003) of the prevalence of autism in children of Somali background living in the county of Stockholm, Sweden. In a previous study (birth years 1988-98), the prevalence of autism associated with learning disability was found to be three to four times higher among Somali children compared with other…

OSSOS. VIII. The Transition between Two Size Distribution Slopes in the Scattering Disk

NASA Astrophysics Data System (ADS)

Lawler, S. M.; Shankman, C.; Kavelaars, J. J.; Alexandersen, M.; Bannister, M. T.; Chen, Ying-Tung; Gladman, B.; Fraser, W. C.; Gwyn, S.; Kaib, N.; Petit, J.-M.; Volk, K.

2018-05-01

The scattering trans-Neptunian Objects (TNOs) can be measured to smaller sizes than any other distant small-body population. We use the largest sample yet obtained, 68 discoveries, primarily by the Outer Solar System Origins Survey (OSSOS), to constrain the slope of its luminosity distribution, with sensitivity to much fainter absolute H-magnitudes than previous work. Using the analysis technique in Shankman et al., we confirm that a single slope for the H-distribution is not an accurate representation of the scattering TNOs and Centaurs, and that a break in the distribution is required, in support of previous conclusions. A bright-end slope of α b = 0.9 transitioning to a faint-end slope α f of 0.4–0.5 with a differential number contrast c from 1 (a knee) to 10 (a divot) provides an acceptable match to our data. We find that break magnitudes H b of 7.7 and 8.3, values both previously suggested for dynamically hot Kuiper Belt populations, are equally non-rejectable for a range of α f and c in our statistical analysis. Our preferred divot H-distribution transitions to α f = 0.5 with a divot of contrast c = 3 at H b = 8.3, while our preferred knee H-distribution transitions to α f = 0.4 at H b = 7.7. The intrinsic population of scattering TNOs required to match the OSSOS detections is 3 × 106 for H r < 12, and 9 × 104 for H r < 8.66 (D ≳ 100 km), with Centaurs having an intrinsic population two orders of magnitude smaller.

Obesity and diabetes in vulnerable populations: reflection on proximal and distal causes.

PubMed

Candib, Lucy M

2007-01-01

Around the world obesity and diabetes are climbing to epidemic proportion, even in countries previously characterized by scarcity. Likewise, people from low-income and minority communities, as well as immigrants from the developing world, increasingly visit physicians in North America with obesity, metabolic syndrome, or diabetes. Explanations limited to lifestyle factors such as diet and exercise are inadequate to explain the universality of what can be called a syndemic, a complex and widespread phenomenon in population health produced by multiple reinforcing conditions. Underlying the problem are complex factors-genetic, physiological, psychological, familial, social, economic, and political-coalescing to overdetermine these conditions. These interacting factors include events occurring during fetal life, maternal physiology and life context, the thrifty genotype, the nutritional transition, health impact of urbanization and immigration, social attributions and cultural perceptions of increased weight, and changes in food costs and availability resulting from globalization. Better appreciation of the complexity of causation underlying the worldwide epidemic of obesity and diabetes can refocus the work of clinicians and researchers to work at multiple levels to address prevention and treatment for these conditions among vulnerable populations.

Color Survey of the Irregular Planetary Satellites

NASA Astrophysics Data System (ADS)

Graykowski, Ariel; Jewitt, David

2017-10-01

Irregular planetary satellites are characterized by their large orbital distance from their planet, their high eccentricity and their high inclination, all indicating that they were captured. However, the mechanism of capture and the source region of the satellites remain subjects of conjecture. This work presents the optical magnitudes and colors from a photometric survey of 42 irregular satellites with data obtained from the LRIS instrument on the 10-meter telescope at the Keck Observatory in Hawaii. Color is used as a proxy for composition. We compare the satellite populations of different planets and compare the satellites as a whole with other solar system small-body populations. For instance, if irregular satellites were captured from the Kuiper Belt, as is commonly proposed, then some might contain the ultrared material that is common in the trans-Neptunian and Centaur populations. Overall our data show that the irregular satellites lack ultrared matter. They are color-wise more similar to the comets, giant planet Trojans and other bodies of the middle solar system. Implications of our observations, and comparisons with previous color work, will be discussed.

Four-year incidence of sick leave because of neck and shoulder pain and its association with work and lifestyle.

PubMed

Alipour, Akbar; Ghaffari, Mostafa; Shariati, Batoul; Jensen, Irene; Vingard, Eva

2009-02-15

Four-year prospective cohort study. To find the incidence of sick leave because of neck and shoulder pain (NSP) in industrial workers, and its association with work and lifestyle risk factors. Longitudinal studies to investigate NSP incidence and risk factors are rare, and even fewer have been conducted in middle- and low-income countries. After inviting all full-time employees of an Iranian car manufacturing company with 18,031 employees to participate in a baseline study, they were followed for 4 years. New episodes of sick leave because of NSP have been calculated based on sickness absence registration between the years 2003 and 2007. The incidence was compared for participants and nonparticipants. The association between sick leave, physical, and psychosocial risk factors at work, and previous self-reported NSP, was calculated for the remaining population of baseline participants (12,184 employees) during a 4-year follow-up. During a 4-year follow-up of study subjects for the remaining participants of the baseline study, the incidence of sick leave was 0.8% (98 sick leave cases in 12,184 employees). For nonparticipants this incidence was 4.2% (130 cases in 3127 employees). In the final regression model for sick leave cases, the remaining factors for potential physical risk factors were repetitive work and sitting positions at work; for psychosocial factors unattractive work was the only significant remaining factor. The incidence of NSP based on sick leave is definitely very low compared with previous studies in high-income countries. This incidence varies between participants and nonparticipants. Risk factors for sick leave differ from risk factors for self-reported pain. A young population, job security, the insurance system, different health behaviors, and healthy worker bias, are all factors that may affect the results, and sick-leave as an outcome must be interpreted with more caution in middle- and low-income countries.

Population density controls on microbial pollution across the Ganga catchment.

PubMed

Milledge, D G; Gurjar, S K; Bunce, J T; Tare, V; Sinha, R; Carbonneau, P E

2018-01-01

For millions of people worldwide, sewage-polluted surface waters threaten water security, food security and human health. Yet the extent of the problem and its causes are poorly understood. Given rapid widespread global urbanisation, the impact of urban versus rural populations is particularly important but unknown. Exploiting previously unpublished archival data for the Ganga (Ganges) catchment, we find a strong non-linear relationship between upstream population density and microbial pollution, and predict that these river systems would fail faecal coliform standards for irrigation waters available to 79% of the catchment's 500 million inhabitants. Overall, this work shows that microbial pollution is conditioned by the continental-scale network structure of rivers, compounded by the location of cities whose growing populations contribute c. 100 times more microbial pollutants per capita than their rural counterparts. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Emergent long-range synchronization of oscillating ecological populations without external forcing described by Ising universality

PubMed Central

Noble, Andrew E.; Machta, Jonathan; Hastings, Alan

2015-01-01

Understanding the synchronization of oscillations across space is fundamentally important to many scientific disciplines. In ecology, long-range synchronization of oscillations in spatial populations may elevate extinction risk and signal an impending catastrophe. The prevailing assumption is that synchronization on distances longer than the dispersal scale can only be due to environmental correlation (the Moran effect). In contrast, we show how long-range synchronization can emerge over distances much longer than the length scales of either dispersal or environmental correlation. In particular, we demonstrate that the transition from incoherence to long-range synchronization of two-cycle oscillations in noisy spatial population models is described by the Ising universality class of statistical physics. This result shows, in contrast to all previous work, how the Ising critical transition can emerge directly from the dynamics of ecological populations. PMID:25851364

Thermodynamics and Human Population

NASA Astrophysics Data System (ADS)

Cordry, Sean M.

2010-09-01

This paper discusses a Fermi-problem exercise through which I take students in several of my college courses. Students work in teams, determining the average daily Caloric needs per person. Then they use insolation values to determine the size of a collection area needed to absorb the previously determined daily energy requirements. Adjustments to the size of the collection area are made based on energy absorption per biological trophic level, as well as the consideration that most diets are a mixture of plant- and animal-derived elements. Finally, using the total amount of farmland available on the planet, students calculate a maximum population value. Although the maximum population values derived herewith should not be considered authoritative, the exercise has three beneficial purposes: 1) a chance to talk about the modeling process and extrapolations, 2) an unexpected application of physics to social contexts, and 3) raising student awareness of population and energy issues.

A GHEP-ISFG collaborative study on the genetic variation of 38 autosomal indels for human identification in different continental populations.

PubMed

Pereira, R; Alves, C; Aler, M; Amorim, A; Arévalo, C; Betancor, E; Braganholi, D; Bravo, M L; Brito, P; Builes, J J; Burgos, G; Carvalho, E F; Castillo, A; Catanesi, C I; Cicarelli, R M B; Coufalova, P; Dario, P; D'Amato, M E; Davison, S; Ferragut, J; Fondevila, M; Furfuro, S; García, O; Gaviria, A; Gomes, I; González, E; Gonzalez-Liñan, A; Gross, T E; Hernández, A; Huang, Q; Jiménez, S; Jobim, L F; López-Parra, A M; Marino, M; Marques, S; Martínez-Cortés, G; Masciovecchio, V; Parra, D; Penacino, G; Pinheiro, M F; Porto, M J; Posada, Y; Restrepo, C; Ribeiro, T; Rubio, L; Sala, A; Santurtún, A; Solís, L S; Souto, L; Streitemberger, E; Torres, A; Vilela-Lamego, C; Yunis, J J; Yurrebaso, I; Gusmão, L

2018-01-01

A collaborative effort was carried out by the Spanish and Portuguese Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) to promote knowledge exchange between associate laboratories interested in the implementation of indel-based methodologies and build allele frequency databases of 38 indels for forensic applications. These databases include populations from different countries that are relevant for identification and kinship investigations undertaken by the participating laboratories. Before compiling population data, participants were asked to type the 38 indels in blind samples from annual GHEP-ISFG proficiency tests, using an amplification protocol previously described. Only laboratories that reported correct results contributed with population data to this study. A total of 5839 samples were genotyped from 45 different populations from Africa, America, East Asia, Europe and Middle East. Population differentiation analysis showed significant differences between most populations studied from Africa and America, as well as between two Asian populations from China and East Timor. Low F ST values were detected among most European populations. Overall diversities and parameters of forensic efficiency were high in populations from all continents. Copyright © 2017 Elsevier B.V. All rights reserved.

Experimental Evolution and Heart Function in Drosophila.

PubMed

Shahrestani, Parvin; Burke, Molly K; Birse, Ryan; Kezos, James N; Ocorr, Karen; Mueller, Laurence D; Rose, Michael R; Bodmer, Rolf

Drosophila melanogaster is a good model species for the study of heart function. However, most previous work on D. melanogaster heart function has focused on the effects of large-effect genetic variants. We compare heart function among 18 D. melanogaster populations that have been selected for altered development time, aging, or stress resistance. We find that populations with faster development and faster aging have increased heart dysfunction, measured as percentage heart failure after electrical pacing. Experimental evolution of different triglyceride levels, by contrast, has little effect on heart function. Evolved differences in heart function correlate with allele frequency changes at many loci of small effect. Genomic analysis of these populations produces a list of candidate loci that might affect cardiac function at the intersection of development, aging, and metabolic control mechanisms.

Inheritable copper tolerance in the chlorophyte macroalga Enteromorpha intestinalis

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

Lewis, S.; Williams, P.; Donkin, M.

1995-12-31

A study was carried out to determine if a population of Enteromorpha intestinalis, from a metal polluted site, exhibited copper tolerance. This work was in preparation for investigating stress protein patterns in copper tolerant and sensitive populations. The effects of copper on growth of E. intestinalis from three clean and one metal polluted site were compared. Growth was assessed by incubating thallus sections in a range of copper solutions and measuring increase in length. Offspring were cultured from clean and polluted sites and the effects of copper on their growth assessed, to determine if any tolerance was inheritable. Concentrations ofmore » the trace metals; copper, zinc and manganese in the populations were also determined. Over the range of copper concentrations tested (0--150 {micro}g/i), growth of the polluted site populations was not significantly affected (P > 0.05). However growth of the clean site populations was significantly depressed by exposure to 50 {micro}g/l. This pattern of response was also exhibited by the offspring. Trace metal concentrations in the clean site populations were very similar, however the polluted site population contained {sup {minus}}10 times the control site values of manganese and {approximately}35 times the values of zinc and copper. The results suggest that the polluted site population of E. intestinalis has developed a degree of copper tolerance which appears to have a genetic basis. This investigation is consistent with previous work into copper tolerance in ship-fouling populations of E. intestinalis var. compressa. A commercially available HSP70 antibody with a high degree of cross-reactivity to E. intestinalis has been identified and used to screen samples of the seaweed from the aforementioned populations.« less

The impact of natural transformation on adaptation in spatially structured bacterial populations.

PubMed

Moradigaravand, Danesh; Engelstädter, Jan

2014-06-20

Recent studies have demonstrated that natural transformation and the formation of highly structured populations in bacteria are interconnected. In spite of growing evidence about this connection, little is known about the dynamics of natural transformation in spatially structured bacterial populations. In this work, we model the interdependency between the dynamics of the bacterial gene pool and those of environmental DNA in space to dissect the effect of transformation on adaptation. Our model reveals that even with only a single locus under consideration, transformation with a free DNA fragment pool results in complex adaptation dynamics that do not emerge in previous models focusing only on the gene shuffling effect of transformation at multiple loci. We demonstrate how spatial restriction on population growth and DNA diffusion in the environment affect the impact of transformation on adaptation. We found that in structured bacterial populations intermediate DNA diffusion rates predominantly cause transformation to impede adaptation by spreading deleterious alleles in the population. Overall, our model highlights distinctive evolutionary consequences of bacterial transformation in spatially restricted compared to planktonic bacterial populations.

Atlantic salmon Salmo salar in the chalk streams of England are genetically unique.

PubMed

Ikediashi, C; Paris, J R; King, R A; Beaumont, W R C; Ibbotson, A; Stevens, J R

2018-03-01

Recent research has identified genetic groups of Atlantic salmon Salmo salar that show association with geological and environmental boundaries. This study focuses on one particular subgroup of the species inhabiting the chalk streams of southern England, U.K. These fish are genetically distinct from other British and European S. salar populations and have previously demonstrated markedly low admixture with populations in neighbouring regions. The genetic population structure of S. salar occupying five chalk streams was explored using 16 microsatellite loci. The analysis provides evidence of the genetic distinctiveness of chalk-stream S. salar in southern England, in comparison with populations from non-chalk regions elsewhere in western Europe. Little genetic differentiation exists between the chalk-stream populations and a pattern of isolation by distance was evident. Furthermore, evidence of temporal stability of S. salar populations across the five chalk streams was found. This work provides new insights into the temporal stability and lack of genetic population sub-structuring within a unique component of the species' range of S. salar. © 2018 The Fisheries Society of the British Isles.

Multiple introductions of the dengue vector, Aedes aegypti, into California

PubMed Central

Gloria-Soria, Andrea; Evans, Benjamin R.; Kramer, Vicki; Bolling, Bethany G.; Tabachnick, Walter J.; Powell, Jeffrey R.

2017-01-01

The yellow fever mosquito Aedes aegypti inhabits much of the tropical and subtropical world and is a primary vector of dengue, Zika, and chikungunya viruses. Breeding populations of A. aegypti were first reported in California (CA) in 2013. Initial genetic analyses using 12 microsatellites on collections from Northern CA in 2013 indicated the South Central US region as the likely source of the introduction. We expanded genetic analyses of CA A. aegypti by: (a) examining additional Northern CA samples and including samples from Southern CA, (b) including more southern US populations for comparison, and (c) genotyping a subset of samples at 15,698 SNPs. Major results are: (1) Northern and Southern CA populations are distinct. (2) Northern populations are more genetically diverse than Southern CA populations. (3) Northern and Southern CA groups were likely founded by two independent introductions which came from the South Central US and Southwest US/northern Mexico regions respectively. (4) Our genetic data suggest that the founding events giving rise to the Northern CA and Southern CA populations likely occurred before the populations were first recognized in 2013 and 2014, respectively. (5) A Northern CA population analyzed at multiple time-points (two years apart) is genetically stable, consistent with permanent in situ breeding. These results expand previous work on the origin of California A. aegypti with the novel finding that this species entered California on multiple occasions, likely some years before its initial detection. This work has implications for mosquito surveillance and vector control activities not only in California but also in other regions where the distribution of this invasive mosquito is expanding. PMID:28796789

Multiple introductions of the dengue vector, Aedes aegypti, into California.

PubMed

Pless, Evlyn; Gloria-Soria, Andrea; Evans, Benjamin R; Kramer, Vicki; Bolling, Bethany G; Tabachnick, Walter J; Powell, Jeffrey R

2017-08-01

The yellow fever mosquito Aedes aegypti inhabits much of the tropical and subtropical world and is a primary vector of dengue, Zika, and chikungunya viruses. Breeding populations of A. aegypti were first reported in California (CA) in 2013. Initial genetic analyses using 12 microsatellites on collections from Northern CA in 2013 indicated the South Central US region as the likely source of the introduction. We expanded genetic analyses of CA A. aegypti by: (a) examining additional Northern CA samples and including samples from Southern CA, (b) including more southern US populations for comparison, and (c) genotyping a subset of samples at 15,698 SNPs. Major results are: (1) Northern and Southern CA populations are distinct. (2) Northern populations are more genetically diverse than Southern CA populations. (3) Northern and Southern CA groups were likely founded by two independent introductions which came from the South Central US and Southwest US/northern Mexico regions respectively. (4) Our genetic data suggest that the founding events giving rise to the Northern CA and Southern CA populations likely occurred before the populations were first recognized in 2013 and 2014, respectively. (5) A Northern CA population analyzed at multiple time-points (two years apart) is genetically stable, consistent with permanent in situ breeding. These results expand previous work on the origin of California A. aegypti with the novel finding that this species entered California on multiple occasions, likely some years before its initial detection. This work has implications for mosquito surveillance and vector control activities not only in California but also in other regions where the distribution of this invasive mosquito is expanding.

Effects of heat stress on working populations when facing climate change.

PubMed

Lundgren, Karin; Kuklane, Kalev; Gao, Chuansi; Holmér, Ingvar

2013-01-01

It is accepted that the earth's climate is changing in an accelerating pace, with already documented implications for human health and the environment. This literature review provides an overview of existing research findings about the effects of heat stress on the working population in relation to climate change. In the light of climate change adaptation, the purpose of the literature review was to explore recent and previous research into the impacts of heat stress on humans in an occupational setting. Heat stress in the workplace has been researched extensively in the past however, in the contemporary context of climate change, information is lacking on its extent and implications. The main factors found to exacerbate heat stress in the current and future workplace are the urban 'heat island effect', physical work, individual differences, and the developing country context where technological fixes are often not applicable. There is also a lack of information on the effects on vulnerable groups such as elderly people and pregnant women. As increasing temperatures reduce work productivity, world economic productivity could be condensed, affecting developing countries in the tropical climate zone disproportionately. Future research is needed taking an interdisciplinary approach, including social, economic, environmental and technical aspects.

Differences in the association between psychosocial work conditions and physical work load in female- and male-dominated occupations. MUSIC-Norrtälje Study Group.

PubMed

Josephson, M; Pernold, G; Ahlberg-Hultén, G; Härenstam, A; Theorell, T; Vingård, E; Waldenström, M; Hjelm, E W

1999-01-01

This study investigated whether there is a relationship between high physical work load and adverse psychosocial work factors, and whether this relationship is different for women and men. Separate analyses for female registered nurses and assistant nurses were made because these are common occupations involving high physical and psychological demands. This study was part of the MUSIC-Norrtälje study, a population study with the overall aim of identifying risk factors for musculoskeletal disorders. The respondents, 1423 gainfully employed men and women, were randomly selected from the study population. The exposure assessments referred to a typical workday during the previous 12 months. Physical exposure was investigated by interview, psychosocial work factors by interview and questionnaire. For the women, but not the men, mainly routine work and a job strain situation, according to the model of Karasek and Theorell, increased the probability of having a high physical work load, assessed as a time-weighted average of energy expenditure in multiples of the resting metabolic rate. Results indicated that in female-dominated occupations, high physical work load might also imply adverse psychosocial conditions. A higher frequency of high physical work load and job strain was observed among assistant nurses compared with registered nurses. Covariance between physical and psychosocial demands makes it difficult to determine the relative influence of each in health problems. Results of the present study imply that this is a larger problem in studies of women than men.

Understanding the Implications of Neural Population Activity on Behavior

NASA Astrophysics Data System (ADS)

Briguglio, John

Learning how neural activity in the brain leads to the behavior we exhibit is one of the fundamental questions in Neuroscience. In this dissertation, several lines of work are presented to that use principles of neural coding to understand behavior. In one line of work, we formulate the efficient coding hypothesis in a non-traditional manner in order to test human perceptual sensitivity to complex visual textures. We find a striking agreement between how variable a particular texture signal is and how sensitive humans are to its presence. This reveals that the efficient coding hypothesis is still a guiding principle for neural organization beyond the sensory periphery, and that the nature of cortical constraints differs from the peripheral counterpart. In another line of work, we relate frequency discrimination acuity to neural responses from auditory cortex in mice. It has been previously observed that optogenetic manipulation of auditory cortex, in addition to changing neural responses, evokes changes in behavioral frequency discrimination. We are able to account for changes in frequency discrimination acuity on an individual basis by examining the Fisher information from the neural population with and without optogenetic manipulation. In the third line of work, we address the question of what a neural population should encode given that its inputs are responses from another group of neurons. Drawing inspiration from techniques in machine learning, we train Deep Belief Networks on fake retinal data and show the emergence of Garbor-like filters, reminiscent of responses in primary visual cortex. In the last line of work, we model the state of a cortical excitatory-inhibitory network during complex adaptive stimuli. Using a rate model with Wilson-Cowan dynamics, we demonstrate that simple non-linearities in the signal transferred from inhibitory to excitatory neurons can account for real neural recordings taken from auditory cortex. This work establishes and tests a variety of hypotheses that will be useful in helping to understand the relationship between neural activity and behavior as recorded neural populations continue to grow.

Prevalence of Self-Reported Work-Related Injuries and Their Association with Psychological Symptoms in General Working Population of Taiwan.

PubMed

Chung, Pei-Hua; Cheng, Yawen

2017-06-01

Objectives This study investigated the prevalence of self-reported work-related injuries across occupational groups and examined their association with the risk of psychological symptoms in general working population of Taiwan. Methods Data from a national survey conducted in 2013 of a representative sample of general working people of Taiwan was analyzed, consisting of 12,528 male and 8396 female workers aged 25~65 years. Information about work-related injuries including work-related disease occurred over the previous 12 months prior to the survey was obtained by a standardized questionnaire. The presence of psychological symptoms was assessed by the Brief Symptom Rating Scale (BSRS). Also obtained were participants' socio-demographic characteristics, working hours, job control, psychological job demands, physical job demands and job insecurity. Results Over a year, 14.91 % of male and 11.53 % of female working people had experienced work-related injuries. Workers with lower educational level, manual workers, the self-employed as well as employers of small enterprise were at higher risks for work-related injuries. Findings from multivariate logistic regression analyses with adjustment of gender, age, working hours and psychosocial work conditions showed that employees with experiences of work-related injuries over the past year were at a substantially higher risk for psychological symptoms (OR = 2.42) as compared to employees who had no experiences of work-related injuries. Conclusion A sizable proportion of workers are affected by work-related injuries and these workers are at higher risk for psychological symptoms. The psychosocial consequences of work-related injuries deserve further investigation and interventions.

Health-Related Quality of Life of Low-Socioeconomic-Status Populations in Urban China.

PubMed

Wu, Lei; Zhang, Huiping

2016-11-20

Previous researchers had not yet examined the association between socioeconomic status (SES) and health-related quality of life (HRQOL) in urban China. The present study attempts to assess HRQOL of lower-SES populations in urban China in comparison with middle- and high-SES populations, and then to examine the mediating role of sense of control between SES and HRQOL. A national representative sample of 1,856 participants responded to the HRQOL survey using the 12-item Short Form Health Survey (SF-12), conducted by the Chinese General Social Survey research team in 2010. The results showed that lower-SES populations reported lower HRQOL than middle- and high-SES populations. Sense of control could partially mediate the association between social class and HRQOL. These findings will generate significant policy and practice implications for identifying those at particular risk for lower HRQOL and, accordingly, suggesting ways to improve their HRQOL through specific social work interventions in urban China's context. © 2016 National Association of Social Workers.

High genetic diversity and absence of founder effects in a worldwide aquatic invader.

PubMed

Lejeusne, Christophe; Saunier, Alice; Petit, Nicolas; Béguer, Mélanie; Otani, Michio; Carlton, James T; Rico, Ciro; Green, Andy J

2014-07-24

The introduced oriental shrimp Palaemon macrodactylus has recently become widespread in temperate estuaries worldwide. However, this recent worldwide spread outside of its native range arises after a previous introduction to the US Pacific coast, where it was restricted for more than 30 years. Using a phylogeographic approach, the present work investigates the genetic history of the invasion of this decapod worldwide. Japan acted as the main native source area for worldwide introduced populations, but other native areas (likely South Korea and China) may act as source populations as well. The recently introduced European and NW Atlantic populations result from colonization from both Japan and an unknown area of the native range, although colonization from the NE Pacific could not be ruled out. Most introduced populations had higher haplotypic diversity than most native populations. P. macrodactylus has a strong potential to become one of the most widespread introduced species and may become the dominant estuarine shrimp in Europe. The ecological and economic consequences of this invasion remain to be thoroughly evaluated.

The Epidemiology of Delirium: Challenges and Opportunities for Population Studies

PubMed Central

Davis, Daniel H.J.; Kreisel, Stefan H.; Muniz Terrera, Graciela; Hall, Andrew J.; Morandi, Alessandro; Boustani, Malaz; Neufeld, Karin J.; Lee, Hochang Benjamin; MacLullich, Alasdair M.J.; Brayne, Carol

2013-01-01

Delirium is a serious and common acute neuropsychiatric syndrome that is associated with short- and long-term adverse health outcomes. However, relatively little delirium research has been conducted in unselected populations. Epidemiologic research in such populations has the potential to resolve several questions of clinical significance in delirium. Part 1 of this article explores the importance of population selection, case-ascertainment, attrition, and confounding. Part 2 examines a specific question in delirium epidemiology: What is the relationship between delirium and trajectories of cognitive decline? This section assesses previous work through two systematic reviews and proposes a design for investigating delirium in the context of longitudinal cohort studies. Such a design requires robust links between community and hospital settings. Practical considerations for case-ascertainment in the hospital, as well as the necessary quality control of these programs, are outlined. We argue that attention to these factors is important if delirium research is to benefit fully from a population perspective. PMID:23907068

The red supergiant population in the Perseus arm

NASA Astrophysics Data System (ADS)

Dorda, R.; Negueruela, I.; González-Fernández, C.

2018-04-01

We present a new catalogue of cool supergiants in a section of the Perseus arm, most of which had not been previously identified. To generate it, we have used a set of well-defined photometric criteria to select a large number of candidates (637) that were later observed at intermediate resolution in the infrared calcium triplet spectral range, using a long-slit spectrograph. To separate red supergiants from luminous red giants, we used a statistical method, developed in previous works and improved in the present paper. We present a method to assign probabilities of being a red supergiant to a given spectrum and use the properties of a population to generate clean samples, without contamination from lower luminosity stars. We compare our identification with a classification done using classical criteria and discuss their respective efficiencies and contaminations as identification methods. We confirm that our method is as efficient at finding supergiants as the best classical methods, but with a far lower contamination by red giants than any other method. The result is a catalogue with 197 cool supergiants, 191 of which did not appear in previous lists of red supergiants. This is the largest coherent catalogue of cool supergiants in the Galaxy.

Perceived health and work-environment related problems and associated subjective production loss in an academic population.

PubMed

Lohela-Karlsson, Malin; Nybergh, Lotta; Jensen, Irene

2018-02-14

The aim was to investigate the prevalence of health problems and work environment problems and how these are associated with subjective production loss among women and men at an academic workplace. An additional aim was to investigate whether there were differences between women and men according to age group, years at current workplace, academic rank or managerial position. A questionnaire was sent in 2011 to all employees at a Swedish university (n = 5144). Only researchers and teachers were included in the study (n = 3207). Spearman correlations were performed to investigate differences in health and work environment problems. Employees who reported having experienced work environment or health problems in the previous seven days (n = 1475) were included in the analyses in order to investigate differences in subjective production loss. This was done using Student's t-test, One-way Anova and generalized linear models. The response rate was 63% (n = 2022). A total of 819 academic staff (40% of the population) reported experiencing either health problems, work environment problems or both during the previous seven days. The prevalence of health problems only or a combination of work environment and health problems was higher among women than men (p-value ˂0.05). This was especially the case for younger women, those in lower academic positions and those who had worked for fewer years at their current workplace. No difference was found for work environment problems. The majority of the employees who reported problems said that these problems affected their ability to perform at work (84-99%). The average production loss varied between 31 and 42% depending on the type of problem. Production loss due to health-related and work-environment related problems was highest among junior researchers and managers. No significant difference between men and women was found in the level of production loss. Subjective production loss in academia can be associated with health and work- environment problems. These losses appear similar for women and men even though younger female academics, women in lower academic ranks and those with fewer years of employment in their current workplace report a higher prevalence of health problems and combined work-environment and health problems than men.

Early predictors of occupational back reinjury: results from a prospective study of workers in Washington State.

PubMed

Keeney, Benjamin J; Turner, Judith A; Fulton-Kehoe, Deborah; Wickizer, Thomas M; Chan, Kwun Chuen Gary; Franklin, Gary M

2013-01-15

Prospective population-based cohort study. To identify early predictors of self-reported occupational back reinjury within 1 year after work-related back injury. Back injuries are the costliest and most prevalent disabling occupational injuries in the United States. A substantial proportion of workers with back injuries have reinjuries after returning to work, yet there are few studies of risk factors for occupational back reinjuries. We aimed to identify the incidence and early (in the claim) predictors of self-reported back reinjury by approximately 1 year after the index injury among Washington State workers with new work disability claims for back injuries. The Washington Workers' Compensation Disability Risk Identification Study Cohort provided a large, population-based sample with information on variables in 7 domains: sociodemographic, employment-related, pain and function, clinical status, health care, health behavior, and psychological. We conducted telephone interviews with workers 3 weeks and 1 year after submission of a time-loss claim for the injury. We first identified predictors (P < 0.10) of self-reported reinjury within 1 year in bivariate analyses. Those variables were then included in a multivariate logistic regression model predicting occupational back reinjury. A total of 290 (25.8%) of 1123 (70.0% response rate) workers who completed the 1-year follow-up interview and had returned to work reported having reinjured their back at work. Baseline variables significantly associated with reinjury (P < 0.05) in the multivariate model included male sex, constant whole-body vibration at work, previous similar injury, 4 or more previous claims of any type, possessing health insurance, and high fear-avoidance scores. Baseline obesity was associated with reduced odds of reinjury. No other employment-related or psychological variables were significant. One-fourth of the workers who received work disability compensation for a back injury self-reported reinjury after returning to work. Baseline variables in multiple domains predicted occupational back reinjury. Increased knowledge of early risk factors for reinjury may help to lead to interventions, such as efforts to reduce fear avoidance and graded activity to promote recovery, effective in lowering the risk of reinjury.

Evaluation of Stress and a Stress-Reduction Program Among Radiologic Technologists.

PubMed

Reingold, Lynn

2015-01-01

To investigate stress levels and causes of stress among radiologic technologists and determine whether an intervention could reduce stress in a selected radiologic technologist population. Demographic characteristics and data on preintervention stress sources and levels were collected through Internet-based questionnaires. A 6-week, self-administered, mindfulness-based stress-reduction program was conducted as a pilot intervention with 42 radiologic technologists from the Veterans Administration Medical Center. Data also were collected postintervention. Identified sources of stress were compared with findings from previous studies. Some radiologic technologists experienced improvement in their perceptions of stress after the intervention. Sources of stress for radiologic technologists were similar to those shown in earlier research, including inconsistent management, poor management communication, conflicting demands, long work hours, excessive workloads, lack of work breaks, and time pressures. The mindfulness-based stress-reduction program is an example of an inexpensive method that could improve personal well-being, reduce work errors, improve relationships in the workplace, and increase job satisfaction. More research is needed to determine the best type of intervention for stress reduction in a larger radiologic technologist population.

SSR characterization of Oryza glumaepatula populations from the Brazilian Amazon and Cerrado biomes.

PubMed

Abreu, Aluana Gonçalves; Rosa, Thalita Marra; Borba, Tereza Cristina de Oliveira; Vianello, Rosana Pereira; Rangel, Paulo Hideo Nakano; Brondani, Claudio

2015-08-01

The level and distribution of the genetic variability in 18 natural populations of Oryza glumaepatula that were collected from two Brazilian states were estimated using a set of 23 highly informative SSR markers. Samples comprising 78 and 117 individuals from populations of the states of Tocantins and Roraima, respectively, were evaluated in order to integrate and support previous studies that were carried out with populations of O. glumaepatula from Brazil. A total of 189 alleles were identified with an average of 8.22 alleles per locus. The 11 populations from Roraima presented, in combination, a higher genetic diversity (HE = 0.245) compared with that of the seven populations from Tocantins (HE = 0.212). All of the populations showed high and significant inbreeding values (mean f = 0.59); however, the mean was higher in Tocantins populations, indicating a higher gene flow in Roraima populations. The overall coefficient of genetic differentiation (FST) among the populations was high and significant (0.59) and was higher in Tocantins due to the isolation of each population, in contrast to Roraima, where gene flow occurred more frequently. The SSR panel used in this work resulted to be informative (polymorphism information content = 0.201) for assessing genetic structure in O. glumaepatula populations.

An fMRI investigation of cerebellar function during verbal working memory in methadone maintenance patients.

PubMed

Marvel, Cherie L; Faulkner, Monica L; Strain, Eric C; Mintzer, Miriam Z; Desmond, John E

2012-03-01

Working memory is impaired in opioid-dependent individuals, yet the neural underpinnings of working memory in this population are largely unknown. Previous studies in healthy adults have demonstrated that working memory is supported by a network of brain regions that includes a cerebro-cerebellar circuit. The cerebellum, in particular, may be important for inner speech mechanisms that assist verbal working memory. This study used functional magnetic resonance imaging to examine brain activity associated with working memory in five opioid-dependent, methadone-maintained patients and five matched, healthy controls. An item recognition task was administered in two conditions: (1) a low working memory load "match" condition in which participants determined whether target letters presented at the beginning of the trial matched a probe item, and (2) a high working memory load "manipulation" condition in which participants counted two alphabetical letters forward of each of the targets and determined whether either of these new items matched a probe item. Response times and accuracy scores were not significantly different between the groups. FMRI analyses indicated that, in association with higher working memory load ("manipulation" condition), the patient group exhibited hyperactivity in the superior and inferior cerebellum and amygdala relative to that of controls. At a more liberal statistical threshold, patients exhibited hypoactivity in the left prefrontal and medial frontal/pre-SMA regions. These results indicate that verbal working memory in opioid-dependent individuals involves a disrupted cerebro-cerebellar circuit and shed light on the neuroanatomical basis of working memory impairments in this population.

An fMRI Investigation of Cerebellar Function During Verbal Working Memory in Methadone Maintenance Patients

PubMed Central

Marvel, Cherie L.; Faulkner, Monica L.; Strain, Eric C.; Mintzer, Miriam Z.; Desmond, John E.

2011-01-01

Working memory is impaired in opioid-dependent individuals, yet the neural underpinnings of working memory in this population are largely unknown. Previous studies in healthy adults have demonstrated that working memory is supported by a network of brain regions that includes a cerebro-cerebellar circuit. The cerebellum, in particular, may be important for inner speech mechanisms that assist verbal working memory. This study used functional magnetic resonance imaging (fMRI) to examine brain activity associated with working memory in 5 opioid-dependent, methadone-maintained patients and 5 matched, healthy controls. An item recognition task was administered in two conditions: 1) a low working memory load “match” condition in which participants determined whether target letters presented at the beginning of the trial matched a probe item, and 2) a high working memory load “manipulation” condition in which participants counted two alphabetical letters forward of each of the targets and determined whether either of these new items matched a probe item. Response times and accuracy scores were not significantly different between the groups. FMRI analyses indicated that, in association with higher working memory load (“manipulation” condition), the patient group exhibited hyperactivity in the superior and inferior cerebellum and amygdala relative to that of controls. At a more liberal statistical threshold, patients exhibited hypoactivity in the left prefrontal and medial frontal/pre-SMA regions. These results indicate that verbal working memory in opioid-dependent individuals involves a disrupted cerebro-cerebellar circuit, and shed light on the neuroanatomical basis of working memory impairments in this population. PMID:21892700

Return to Work After Acute Myocardial Infarction: Comparison Between Young Women and Men.

PubMed

Dreyer, Rachel P; Xu, Xiao; Zhang, Weiwei; Du, Xue; Strait, Kelly M; Bierlein, Maggie; Bucholz, Emily M; Geda, Mary; Fox, James; D'Onofrio, Gail; Lichtman, Judith H; Bueno, Héctor; Spertus, John A; Krumholz, Harlan M

2016-02-01

Return to work after acute myocardial infarction (AMI) is an important outcome and is particularly relevant to young patients. Women may be at a greater risk for not returning to work given evidence of their worse recovery after AMI than similarly aged men. However, sex differences in return to work after AMI has not been studied extensively in a young population (≤ 55 years). We analyzed data from 1680 patients with AMI aged 18 to 55 years (57% women) participating in the Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients (VIRGO) study who were working full time (≥ 35 hours) before the event. Data were obtained by medical record abstraction and patient interviews. We conducted multivariable regression analyses to examine sex differences in return to work at 12 months after AMI, and the association of patient characteristics with return to work. When compared with young men, young women were less likely to return to work (89% versus 85%; 85% versus 89%, P=0.02); however, this sex difference was not significant after adjusting for patient sociodemographic characteristics, psychosocial factors, and health measures. Being married, engaging in a professional or clerical type of work, having more favorable physical health, and having no previous coronary disease or hypertension were significantly associated with a higher likelihood of return to work at 12 months. Among a young population, women are less likely to return to work after AMI than men. This disadvantage is explained by differences in demographic, occupational, and health characteristics. © 2016 American Heart Association, Inc.

Balanced Cortical Microcircuitry for Spatial Working Memory Based on Corrective Feedback Control

PubMed Central

2014-01-01

A hallmark of working memory is the ability to maintain graded representations of both the spatial location and amplitude of a memorized stimulus. Previous work has identified a neural correlate of spatial working memory in the persistent maintenance of spatially specific patterns of neural activity. How such activity is maintained by neocortical circuits remains unknown. Traditional models of working memory maintain analog representations of either the spatial location or the amplitude of a stimulus, but not both. Furthermore, although most previous models require local excitation and lateral inhibition to maintain spatially localized persistent activity stably, the substrate for lateral inhibitory feedback pathways is unclear. Here, we suggest an alternative model for spatial working memory that is capable of maintaining analog representations of both the spatial location and amplitude of a stimulus, and that does not rely on long-range feedback inhibition. The model consists of a functionally columnar network of recurrently connected excitatory and inhibitory neural populations. When excitation and inhibition are balanced in strength but offset in time, drifts in activity trigger spatially specific negative feedback that corrects memory decay. The resulting networks can temporally integrate inputs at any spatial location, are robust against many commonly considered perturbations in network parameters, and, when implemented in a spiking model, generate irregular neural firing characteristic of that observed experimentally during persistent activity. This work suggests balanced excitatory–inhibitory memory circuits implementing corrective negative feedback as a substrate for spatial working memory. PMID:24828633

Inferring population structure and demographic history using Y-STR data from worldwide populations.

PubMed

Xu, Hongyang; Wang, Chuan-Chao; Shrestha, Rukesh; Wang, Ling-Xiang; Zhang, Manfei; He, Yungang; Kidd, Judith R; Kidd, Kenneth K; Jin, Li; Li, Hui

2015-02-01

The Y chromosome is one of the best genetic materials to explore the evolutionary history of human populations. Global analyses of Y chromosomal short tandem repeats (STRs) data can reveal very interesting world population structures and histories. However, previous Y-STR works tended to focus on small geographical ranges or only included limited sample sizes. In this study, we have investigated population structure and demographic history using 17 Y chromosomal STRs data of 979 males from 44 worldwide populations. The largest genetic distances have been observed between pairs of African and non-African populations. American populations with the lowest genetic diversities also showed large genetic distances and coancestry coefficients with other populations, whereas Eurasian populations displayed close genetic affinities. African populations tend to have the oldest time to the most recent common ancestors (TMRCAs), the largest effective population sizes and the earliest expansion times, whereas the American, Siberian, Melanesian, and isolated Atayal populations have the most recent TMRCAs and expansion times, and the smallest effective population sizes. This clear geographic pattern is well consistent with serial founder model for the origin of populations outside Africa. The Y-STR dataset presented here provides the most detailed view of worldwide population structure and human male demographic history, and additionally will be of great benefit to future forensic applications and population genetic studies.

The relationship between work stress and work ability among power supply workers in Guangdong, China: a cross-sectional study.

PubMed

Li, Hualiang; Liu, Zhiting; Liu, Runzhong; Li, Li; Lin, Aihua

2016-02-06

Faced with the challenge of population aging, a prolonged working life is increasingly important in today's society. Maintaining work ability of employees is one of the effective ways to cope with the challenges to sustainability of the workforce presented by population aging. Researchers have shown ongoing interest in exploring the determinants of restricted work ability. The aim of this study was to evaluate the effects of work stress on work ability among power supply workers in Guangdong, China. A cross-sectional study was conducted among power supply workers during August 2014 to September 2014. A total of 805 subjects were enrolled in the study. Work stress was assessed by the Job Content Questionnaire and the Effort Reward Imbalance Questionnaire. Work ability was assessed by the Work Ability Index (WAI). The structural equation model was applied to test the relationship between different work stress components and work ability simultaneously using the Job Demands-Resources model as a framework. Job resources (measured by job control, reward and social support) were positively and directly associated with work ability (β = 0.70, P < 0.001). The association between job demands and work ability was also statistically significant (β = -0.09, P = 0.030). In addition, the findings also supported previous studies in that job demands were correlated with job resources (β = -0.26, P < 0.001). Our findings suggest that decision makers and health care providers should consider increasing job resources available to power supply workers. Consideration of organizational changes related to the design of the job task also would be useful to improve the employees' work ability.

Development and validation of a web-based questionnaire for surveying the health and working conditions of high-performance marine craft populations

PubMed Central

de Alwis, Manudul Pahansen; Lo Martire, Riccardo; Äng, Björn O; Garme, Karl

2016-01-01

Background High-performance marine craft crews are susceptible to various adverse health conditions caused by multiple interactive factors. However, there are limited epidemiological data available for assessment of working conditions at sea. Although questionnaire surveys are widely used for identifying exposures, outcomes and associated risks with high accuracy levels, until now, no validated epidemiological tool exists for surveying occupational health and performance in these populations. Aim To develop and validate a web-based questionnaire for epidemiological assessment of occupational and individual risk exposure pertinent to the musculoskeletal health conditions and performance in high-performance marine craft populations. Method A questionnaire for investigating the association between work-related exposure, performance and health was initially developed by a consensus panel under four subdomains, viz. demography, lifestyle, work exposure and health and systematically validated by expert raters for content relevance and simplicity in three consecutive stages, each iteratively followed by a consensus panel revision. The item content validity index (I-CVI) was determined as the proportion of experts giving a rating of 3 or 4. The scale content validity index (S-CVI/Ave) was computed by averaging the I-CVIs for the assessment of the questionnaire as a tool. Finally, the questionnaire was pilot tested. Results The S-CVI/Ave increased from 0.89 to 0.96 for relevance and from 0.76 to 0.94 for simplicity, resulting in 36 items in the final questionnaire. The pilot test confirmed the feasibility of the questionnaire. Conclusions The present study shows that the web-based questionnaire fulfils previously published validity acceptance criteria and is therefore considered valid and feasible for the empirical surveying of epidemiological aspects among high-performance marine craft crews and similar populations. PMID:27324717

Correcting for compensating mechanisms related to productivity costs in economic evaluations of health care programmes.

PubMed

Jacob-Tacken, Karin H M; Koopmanschap, Marc A; Meerding, Willem Jan; Severens, Johan L

2005-05-01

In the economic evaluation of health care programmes, productivity costs are often estimated using patients' wages for the period of absence. However, the use of such methods for short periods of absence is controversial. A previous study found that short-term absence is often compensated for during normal working hours and therefore does not lead to productivity losses. As such, the application of any approach almost certainly overestimates productivity costs. In this study, we examined the productivity costs for five different patient populations and one employee population, using the classical method and by identifying when extra effort was needed. In general, the results showed that productivity costs based on identifying extra effort were 25-30% of the classical estimates. For absences of just one day, productivity costs were relevant in only 17-19% of cases. For absences of two weeks or longer, productivity costs were relevant in 35-39% of cases. Measurement of the compensating mechanisms seemed to be valid, since there is considerable agreement between the opinion of supervisors and their employees about whether compensation covers productivity costs. There was much less agreement between supervisors and their employees on specific compensating mechanisms, however. The measurement of compensating mechanisms also seemed to be valid, because--as expected--different compensating mechanisms were reported for different occupations. In our study populations, compensating mechanisms appeared to differ with occupational characteristics, like part-time work, managerial work and shift work. Copyright 2004 John Wiley & Sons, Ltd

Direct foreign investment: a migration push-factor?

PubMed

Sassen-koob, S

1984-01-01

Policymakers and analysts now recognize that US military activities abroad contribute to the creation of refugee flows into the US. Previously, immigration into the US was viewed as a result of inept and failed domestic policies in the countries of origin. Results show that recent immigrants to the US come from countries with neither the poorest nor the largest population growth rate in the less developed world. However, the sending countries received US direct foreign investment (DFI) in the 1970s, particularly labor intensive investment in export manufacturing. Significant levels and concentrations of DFI promote emigration through: 1) the incorporation of new segments of the population into wage labor and the associated disruption of traditional work structures, 2) the feminization of the new industrial work force and its impact on the work opportunities of men, and 3) the consolidation of objective and ideological links with the highly industrialized countries where most foreign capital originates. The data suggest an examination of the causes of emigration on a much more specific level than that of underdevelopment, poverty, and population growth. These facts carry immediate policy implications for US immigration organizations: 1) if US firms in export processing zones recruited workers from the pool of unemployed--mostly prime-age males--rather than expanding the labor supply by recruiting young women, thereby disrupting unwaged work structures, and 2) if these firms would desist from having high turnover rates among workers, then the migration impact of this type of development would be minimized.

Prevalence of upper limb disorders among female librarians.

PubMed

Pandy, R

2013-09-01

Work as a librarian involves exposure to potential risk factors for developing upper limb disorders. The prevalence of upper limb symptoms has, however, not previously been assessed in this occupational group. To estimate the 7-day and annual prevalence of self-reported neck and upper limb symptoms in librarians and to examine associations with specific tasks and ergonomic risk factors. A cross-sectional study using components of the standardized Nordic questionnaire. The study population consisted of librarians employed by a large local authority, and data collection was by means of a self-administered questionnaire. from studies on keyboard workers and on the general population were used as comparators. The 7-day prevalence of self-reported neck and upper limb pain in female librarians was 42% (95% confidence interval (CI) 33.7-50.5) and the annual prevalence was 65% (95% CI 56.6-72.8). The prevalence of reported wrist and hand pain increased with increased working involving a wide thumb-index span (P < 0.05) with a significant linear trend in prevalence with increasing exposure (P < 0.01). There was a strong association between reporting hand and/or wrist pain and awareness of work-related upper limb disorder (P < 0.05). The annual prevalence of self-reported upper limb symptoms among female librarians was high, but there was insufficient evidence to confirm whether the prevalence was higher than in the general population or among keyboard workers. Working with a wide thumb-index span was associated with reporting upper limb symptoms.

Time for children: trends in the employment patterns of parents, 1967-2009.

PubMed

Fox, Liana; Han, Wen-Jui; Ruhm, Christopher; Waldfogel, Jane

2013-02-01

Using data from the 1967-2009 years of the March Current Population Surveys (CPS), we examine two important resources for children's well-being: time and money. We document trends in parental employment, from the perspective of children, and show what underlies these trends. We find that increases in family work hours mainly reflect movements into jobs by parents-particularly mothers, who in prior decades would have remained at home. This increase in market work has raised incomes for children in the typical two-parent family but not for those in lone-parent households. Time use data from 1975 and 2003-2008 reveal that working parents spend less time engaged in primary childcare than their counterparts without jobs but more than employed peers in previous cohorts. Analysis of 2004 work schedule data suggests that non-daytime work provides an alternative method of coordinating employment schedules for some dual-earner families.

Evaluating Teachers' Preparedness to Work With Students Who Are Deaf and Hard of Hearing With Disabilities.

PubMed

Guardino, Caroline

2015-01-01

A national survey was conducted to determine the needs of teachers and service providers working with students who are deaf and hard of hearing with disabilities (DWD). Quantitative and qualitative questions were asked regarding knowledge of, training with, and strategies used with students who are DWD. Responses from 264 professionals working with this population are reported. Results are reviewed and tied to previous research before and after the 2008 revalidation of the Council on Education of the Deaf standards for teachers of the deaf. Final recommendations are made for (a) virtual learning opportunities, (b) hands-on field experiences and course work in teacher preparation programs, and (c) empirically based research. By understanding the needs of professionals who are currently working with students who are DWD, researchers can help improve teacher preparation programs as well as improve the educational systems currently in place for these learners.

Investigating a population of infrared-bright gamma-ray burst host galaxies

NASA Astrophysics Data System (ADS)

Chrimes, Ashley A.; Stanway, Elizabeth R.; Levan, Andrew J.; Davies, Luke J. M.; Angus, Charlotte R.; Greis, Stephanie M. L.

2018-07-01

We identify and explore the properties of an infrared-bright gamma-ray burst (GRB) host population. Candidate hosts are selected by coincidence with sources in WISE, with matching to random coordinates and a false alarm probability analysis showing that the contamination fraction is ˜0.5. This methodology has already identified the host galaxy of GRB 080517. We combine survey photometry from Pan-STARRS, SDSS, APASS, 2MASS, GALEX, and WISE with our own WHT/ACAM and VLT/X-shooter observations to classify the candidates and identify interlopers. Galaxy SED fitting is performed using MAGPHYS, in addition to stellar template fitting, yielding 13 possible IR-bright hosts. A further seven candidates are identified from the previously published work. We report a candidate host for GRB 061002, previously unidentified as such. The remainder of the galaxies have already been noted as potential hosts. Comparing the IR-bright population properties including redshift z, stellar mass M⋆, star formation rate SFR, and V-band attenuation AV to GRB host catalogues in the literature, we find that the infrared-bright population is biased towards low z, high M⋆, and high AV. This naturally arises from their initial selection - local and dusty galaxies are more likely to have the required IR flux to be detected in WISE. We conclude that while IR-bright GRB hosts are not a physically distinct class, they are useful for constraining existing GRB host populations, particularly for long GRBs.

Socioeconomic factors associated with drug consumption in prison population in Mexico.

PubMed

Nevárez-Sida, Armando; Constantino-Casas, Patricia; Castro-Ríos, Angélica

2012-01-13

Consumption of illegal drugs is a public health problem in Mexico, and the prison population is a vulnerable group with higher rates of prevalence than in the general population. The objective of this study was to determine the main socioeconomic variables associated with drug consumption in the prison population. Utilizing data from the Second Incarcerated Population Survey carried out by the Centre of Research and Teaching of Economics (CIDE) in Mexico, a logistic model in two stages was developed. The first stage analyzed the determinants of habitual drug consumption by prisoners (prior to admittance into prisons), while the second stage of the model addressed drug consumption within prisons. Prevalence of drug consumption previous to incarceration was 28.5%, although once people were imprisoned this figure dropped to 7.4%. The characteristics that most heavily influenced against the possibility of habitual drug consumption prior to admittance to prison were: preparatory school or higher, being employed and having children; while the variables associated negatively were: male gender, childhood home shared with adults who consumed illegal drugs; abandoning childhood home; and having previous prison sentences. Once in prison, the negative conditions in there are associated with drug consumption. Work and study during incarceration, in addition to being instruments for rehabilitation, seem to exert an important positive association against drug consumption. However, this correlation seems to be minimized in the face of negative conditions of the penal institution; thus, public policies are necessary to improve the prisoner's environment.

Socioeconomic factors associated with drug consumption in prison population in Mexico

PubMed Central

2012-01-01

Background Consumption of illegal drugs is a public health problem in Mexico, and the prison population is a vulnerable group with higher rates of prevalence than in the general population. The objective of this study was to determine the main socioeconomic variables associated with drug consumption in the prison population. Methods Utilizing data from the Second Incarcerated Population Survey carried out by the Centre of Research and Teaching of Economics (CIDE) in Mexico, a logistic model in two stages was developed. The first stage analyzed the determinants of habitual drug consumption by prisoners (prior to admittance into prisons), while the second stage of the model addressed drug consumption within prisons. Results Prevalence of drug consumption previous to incarceration was 28.5%, although once people were imprisoned this figure dropped to 7.4%. The characteristics that most heavily influenced against the possibility of habitual drug consumption prior to admittance to prison were: preparatory school or higher, being employed and having children; while the variables associated negatively were: male gender, childhood home shared with adults who consumed illegal drugs; abandoning childhood home; and having previous prison sentences. Once in prison, the negative conditions in there are associated with drug consumption. Conclusions Work and study during incarceration, in addition to being instruments for rehabilitation, seem to exert an important positive association against drug consumption. However, this correlation seems to be minimized in the face of negative conditions of the penal institution; thus, public policies are necessary to improve the prisoner's environment. PMID:22244315

Investigating a population of infrared-bright gamma-ray burst host galaxies

NASA Astrophysics Data System (ADS)

Chrimes, Ashley A.; Stanway, Elizabeth R.; Levan, Andrew J.; Davies, Luke J. M.; Angus, Charlotte R.; Greis, Stephanie M. L.

2018-04-01

We identify and explore the properties of an infrared-bright gamma-ray burst (GRB) host population. Candidate hosts are selected by coincidence with sources in WISE, with matching to random coordinates and a false alarm probability analysis showing that the contamination fraction is ˜ 0.5. This methodology has already identified the host galaxy of GRB 080517. We combine survey photometry from Pan-STARRS, SDSS, APASS, 2MASS, GALEX and WISE with our own WHT/ACAM and VLT/X-shooter observations to classify the candidates and identify interlopers. Galaxy SED fitting is performed using MAGPHYS, in addition to stellar template fitting, yielding 13 possible IR-bright hosts. A further 7 candidates are identified from previously published work. We report a candidate host for GRB 061002, previously unidentified as such. The remainder of the galaxies have already been noted as potential hosts. Comparing the IR-bright population properties including redshift z, stellar mass M⋆, star formation rate SFR and V-band attenuation AV to GRB host catalogues in the literature, we find that the infrared-bright population is biased toward low z, high M⋆ and high AV. This naturally arises from their initial selection - local and dusty galaxies are more likely to have the required IR flux to be detected in WISE. We conclude that while IR-bright GRB hosts are not a physically distinct class, they are useful for constraining existing GRB host populations, particularly for long GRBs.

Antagonistic interactions are sufficient to explain self-assemblage of bacterial communities in a homogeneous environment: a computational modeling approach

PubMed Central

Zapién-Campos, Román; Olmedo-Álvarez, Gabriela; Santillán, Moisés

2015-01-01

Most of the studies in Ecology have been devoted to analyzing the effects the environment has on individuals, populations, and communities, thus neglecting the effects of biotic interactions on the system dynamics. In the present work we study the structure of bacterial communities in the oligotrophic shallow water system of Churince, Cuatro Cienegas, Mexico. Since the physicochemical conditions of this water system are homogeneous and quite stable in time, it is an excellent candidate to study how biotic factors influence the structure of bacterial communities. In a previous study, the binary antagonistic interactions of 78 bacterial strains, isolated from Churince, were experimentally determined. We employ these data to develop a computer algorithm to simulate growth experiments in a cellular grid representing the pond. Remarkably, in our model, the dynamics of all the simulated bacterial populations is determined solely by antagonistic interactions. Our results indicate that all bacterial strains (even those that are antagonized by many other bacteria) survive in the long term, and that the underlying mechanism is the formation of bacterial community patches. Patches corresponding to less antagonistic and highly susceptible strains are consistently isolated from the highly-antagonistic bacterial colonies by patches of neutral strains. These results concur with the observed features of the bacterial community structure previously reported. Finally, we study how our findings depend on factors like initial population size, differential population growth rates, homogeneous population death rates, and enhanced bacterial diffusion. PMID:26052318

Short-range phenotypic divergence among genetically distinct parapatric populations of an Australian funnel-web spider.

PubMed

Wong, Mark K L; Woodman, James D; Rowell, David M

2017-07-01

Speciation involves divergence at genetic and phenotypic levels. Where substantial genetic differentiation exists among populations, examining variation in multiple phenotypic characters may elucidate the mechanisms by which divergence and speciation unfold. Previous work on the Australian funnel-web spider Atrax sutherlandi Gray (2010; Records of the Australian Museum 62 , 285-392; Mygalomorphae: Hexathelidae: Atracinae) has revealed a marked genetic structure along a 110-kilometer transect, with six genetically distinct, parapatric populations attributable to past glacial cycles. In the present study, we explore variation in three classes of phenotypic characters (metabolic rate, water loss, and morphological traits) within the context of this phylogeographic structuring. Variation in metabolic and water loss rates shows no detectable association with genetic structure; the little variation observed in these rates may be due to the spiders' behavioral adaptations (i.e., burrowing), which buffer the effects of climatic gradients across the landscape. However, of 17 morphological traits measured, 10 show significant variation among genetic populations, in a disjunct manner that is clearly not latitudinal. Moreover, patterns of variation observed for morphological traits serving different organismic functions (e.g., prey capture, burrowing, and locomotion) are dissimilar. In contrast, a previous study of an ecologically similar sympatric spider with little genetic structure indicated a strong latitudinal response in 10 traits over the same range. The congruence of morphological variation with deep phylogeographic structure in Tallaganda's A. sutherlandi populations, as well as the inconsistent patterns of variation across separate functional traits, suggest that the spiders are likely in early stages of speciation, with parapatric populations independently responding to local selective forces.

[Polymorphism of CD209 and TLR3 genes in populations of North Eurasia].

PubMed

Barkhash, A V; Babenko, V N; Voevoda, M I; Romaschenko, A G

2016-06-01

The DC-SIGN (dendritic cell-specific intercellular adhesion molecule (ICAM)-3-grabbing non-integrin) and TLR3 (toll-like receptor 3) proteins are key effectors of the innate immunity and particularly play an important role in the organism’s antiviral defense as pattern-recognition receptors. Previously, we demonstrated that certain genotypes and alleles of single nucleotide polymorphisms (SNPs) rs2287886 (G/A) in the promoter region of the CD209 gene (encoding DC-SIGN) and rs3775291 (G/A, Leu412Phe) in the exon 4 of the TLR3 gene are associated with human predisposition to tick-borne encephalitis in the Russian population. In the present work, the distribution of genotype and allele frequencies for these SNPs was studied in seven populations of North Eurasia, including Caucasians (Russians and Germans (from Altai region)), Central Asian Mongoloids (Altaians, Khakass, Tuvinians, and Shorians), and Arctic Mongoloids (Chukchi). It was found that the CD209 gene rs2287886 SNP A/A genotype and A allele, as well as the TLR3 gene rs3775291 SNP G/G genotype and G allele (the frequencies of which in our previous studies were increased in tick-borne encephalitis patients as compared with the population control (Russian citizens of Novosibirsk)), are preserved with a high frequency in Central Asian Mongoloids (who for a long time regularly came in contact with tick-borne encephalitis virus in places of their habitation). We suggested that predisposition to tick-borne encephalitis in Central Asian Mongoloid populations can be predetermined by a different set of genes and their polymorphisms than in the Russian population.

Development and validation of a new population-based simulation model of osteoarthritis in New Zealand.

PubMed

Wilson, R; Abbott, J H

2018-04-01

To describe the construction and preliminary validation of a new population-based microsimulation model developed to analyse the health and economic burden and cost-effectiveness of treatments for knee osteoarthritis (OA) in New Zealand (NZ). We developed the New Zealand Management of Osteoarthritis (NZ-MOA) model, a discrete-time state-transition microsimulation model of the natural history of radiographic knee OA. In this article, we report on the model structure, derivation of input data, validation of baseline model parameters against external data sources, and validation of model outputs by comparison of the predicted population health loss with previous estimates. The NZ-MOA model simulates both the structural progression of radiographic knee OA and the stochastic development of multiple disease symptoms. Input parameters were sourced from NZ population-based data where possible, and from international sources where NZ-specific data were not available. The predicted distributions of structural OA severity and health utility detriments associated with OA were externally validated against other sources of evidence, and uncertainty resulting from key input parameters was quantified. The resulting lifetime and current population health-loss burden was consistent with estimates of previous studies. The new NZ-MOA model provides reliable estimates of the health loss associated with knee OA in the NZ population. The model structure is suitable for analysis of the effects of a range of potential treatments, and will be used in future work to evaluate the cost-effectiveness of recommended interventions within the NZ healthcare system. Copyright © 2018 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Does Environmental Knowledge Inhibit Hominin Dispersal?

PubMed

Wren, Colin D; Costopoulos, Andre

2015-07-01

We investigated the relationship between the dispersal potential of a hominin population, its local-scale foraging strategies, and the characteristics of the resource environment using an agent-based modeling approach. In previous work we demonstrated that natural selection can favor a relatively low capacity for assessing and predicting the quality of the resource environment, especially when the distribution of resources is highly clustered. That work also suggested that the more knowledge foraging populations had about their environment, the less likely they were to abandon the landscape they know and disperse into novel territory. The present study gives agents new individual and social strategies for learning about their environment. For both individual and social learning, natural selection favors decreased levels of environmental knowledge, particularly in low-heterogeneity environments. Social acquisition of detailed environmental knowledge results in crowding of agents, which reduces available reproductive space and relative fitness. Agents with less environmental knowledge move away from resource clusters and into areas with more space available for reproduction. These results suggest that, rather than being a requirement for successful dispersal, environmental knowledge strengthens the ties to particular locations and significantly reduces the dispersal potential as a result. The evolved level of environmental knowledge in a population depends on the characteristics of the resource environment and affects the dispersal capacity of the population.

The influence of previous low back trouble, general health, and working conditions on future sick-listing because of low back trouble. A 15-year follow-up study of risk indicators for self-reported sick-listing caused by low back trouble.

PubMed

Müller, C F; Monrad, T; Biering-Sørensen, F; Darre, E; Deis, A; Kryger, P

1999-08-01

A 15-year follow-up study. To find risk indicators for self-reported sick-listing because of low back trouble and to evaluate which variables were the most important indicators of work incapacity resulting from low back trouble during the follow-up period of 15 years. The initial data were obtained from a health survey conducted in a general population from the Municipality of Glostrup, Denmark. The follow-up data included information from the Central Person Register, the Early Retirement Pension Register, and a postal questionnaire regarding self-reported sick-listing because of low back trouble. An epidemiologic study, in which logistic regression analyses were used for evaluation of the data. The model used consisted of the variable in question, age, gender, and previous experience of low back trouble, along with interactions. It was found that 22 of 37 variables were risk indicators for later self-reported sick-listing because of low back trouble during the preceding year or the 7 years before the date of follow-up evaluation. In analyzing the most significant variables simultaneously, it was found that information from the initial investigation about sick-listing in general during the previous 10 years, sciatic pain, use of analgesics for low back trouble, previous sick-listing because of low back trouble, and occupation were the most important risk indicators for self-reported work incapacity resulting from low back trouble during the follow-up period of 15 years. Findings showed that the strongest prognostic indicators of later sick-listing because of low back trouble involve information from the person about previous sick-listing behavior in general and previous experience of low back trouble episodes, especially if these had been accompanied by sciatic pain, use of analgesics, or previous low back trouble sick-listing.

The light pollution as a surrogate for urban population of the US cities

NASA Astrophysics Data System (ADS)

Operti, Felipe G.; Oliveira, Erneson A.; Carmona, Humberto A.; Machado, Javam C.; Andrade, José S.

2018-02-01

We show that the definition of the city boundaries can have a dramatic influence on the scaling behavior of the night-time light (NTL) as a function of population (POP) in the US. Precisely, our results show that the arbitrary geopolitical definition based on the Metropolitan/Consolidated Metropolitan Statistical Areas (MSA/CMSA) leads to a sublinear power-law growth of NTL with POP. On the other hand, when cities are defined according to a more natural agglomeration criteria, namely, the City Clustering Algorithm (CCA), an isometric relation emerges between NTL and population. This discrepancy is compatible with results from previous works showing that the scaling behaviors of various urban indicators with population can be substantially different for distinct definitions of city boundaries. Moreover, considering the CCA definition as more adequate than the MSA/CMSA one because the former does not violate the expected extensivity between land population and area of their generated clusters, we conclude that, without loss of generality, the CCA measures of light pollution and population could be interchangeably utilized in future studies.

India's demographic snapshot, 1991.

PubMed

Bose, A

1991-12-01

Having presented the provisional results of the 1991 Census of India in tabular form, the author discusses the policy implication of the data. During the 1981-91 decade, India witnesses a 160.99 net increase in population, which brought the country's total population to an estimated 844.32 million. The annual growth rated during the decade was 2.1%. The author explains that these alarming population figures reflect the failure of the government's population program. The author warns that unless the Planning Commission develops new strategies, the upcoming 5-year plans. The author explains that the failure of family planning is due primarily to the low literacy rate -- especially the female literacy rate is 29% (and 25% among rural women). The author also discusses the problems of urbanization and the work force. During the past decade, cities grew at a somewhat slower rate than in previous decades, meaning that the absorptive capacity of the cities has gone down. Nonetheless, the urban population grew by 58 million during 10-year period. The urban infrastructure is virtually collapsing, with 30-50% of the urban population living in slums. The data also reveals the structural stagnation of the economy. The agricultural sector, which accounts for about 2/3 of the work force, registered only slight decreases during the decade, signifying a marginal shift from agriculture to nonagricultural activity. Furthermore, population growth has aggravated the unemployment problem. Finally, the author addresses the issue of the sex ratio (females/1000 males), which declined from 934 in 1981 to 929 in 1991, which indicates a continued prejudice against women.

Plasma discharge and time-dependence of its effect to bacteria.

PubMed

Justan, I; Cernohorska, L; Dvorak, Z; Slavicek, P

2014-07-01

Several types of plasma discharge have been proven to have a capacity for sterilization. Our goal is to introduce new nonthermal plasma pencil. We used it to sterilize different microbial populations with differing ages. We used a plasma discharge of the following characteristics: radio frequency barrier discharger at atmospheric pressure with a working frequency of 13.56 MHz, and the working gas used was argon. We performed 110 tests with the following microbial populations: Pseudomonas aeruginosa, Staphylococcus aureus, Proteus species, and Klebsiella pneumoniae. All populations were inoculated on the previous day and also on the day of our experiment. We made our evaluations the following day and also after 5 days, with all our microbial populations. Eradication of microbial populations is dependent on the plasma discharge exposure time in all cases. With regard to freshly inoculated microbes, we were able to sterilize agar with intensive exposure lasting for 10 s of colonies Pseudomonas, Proteus, and Klebsiella. The most resistant microbe seems to be S. aureus, which survives 5 s of coherent exposure in half of the cases. Using the lightest plasma discharge exposure, we achieved a maximum of 10(4)-10(5) CFU/mL (colony-forming unit - CFU). Regarding older microbial populations inoculated the day before the experiment, we can only decrease population growth to 10(5) CFU/mL approximately, but never completely sterilize. The plasma discharge with our characteristics could be used for the sterilization of the aforementioned superficially growing microbes, but does not sufficiently affect deeper layers and thus seems to be a limitation for eradication of the already erupted colonies.

Exploring karyotype diversity of Argentinian Guaraní maize landraces: Relationship among South American maize

PubMed Central

Poggio, Lidia

2018-01-01

In Argentina there are two different centers of maize diversity, the Northeastern (NEA) and the Northwestern (NWA) regions of the country. In NEA, morphological studies identified 15 landraces cultivated by the Guaraní communities in Misiones Province. In the present study we analyzed the karyotype diversity of 20 populations of Guaraní maize landraces through classical and molecular cytogenetic analyses. Our results demonstrate significant intra and inter-populational variation in the percentage, number, size, chromosome position and frequencies of the heterochromatic blocks, which are called knobs. Knob sequence analysis (180-bp and TR-1) did not show significant differences among Guaraní populations. B chromosomes were not detected, and abnormal 10 (AB10) chromosomes were found with low frequency (0.1≥f ≤0.40) in six populations. Our results allowed karyotypic characterization of each analyzed population, defining for the first time the chromosomal constitution of maize germplasm from NEA. The multivariate analysis (PCoA and UPGMA) of karyotype parameters allowed the distinction between two populations groups: the Popcorn and the Floury maize populations. These results are in agreement with previously published microsatellite and morphological/phenological studies. Finally, we compared our karyotype results with those previously reported for NWA and Central Region of South America maize. Our data suggest that there are important differences between maize from NEA and NWA at the karyotype level, supporting the hypothesis that there are two pathways of input of South America maize. Our results also confirm the existence of two centers of diversification of Argentinian native maize, NWA and NEA. This work contributes new knowledge about maize diversity, which is relevant for future plans to improve commercial maize, and for conservation of agrobiodiversity. PMID:29879173

Exploring karyotype diversity of Argentinian Guaraní maize landraces: Relationship among South American maize.

PubMed

Realini, María Florencia; Poggio, Lidia; Cámara Hernández, Julián; González, Graciela Esther

2018-01-01

In Argentina there are two different centers of maize diversity, the Northeastern (NEA) and the Northwestern (NWA) regions of the country. In NEA, morphological studies identified 15 landraces cultivated by the Guaraní communities in Misiones Province. In the present study we analyzed the karyotype diversity of 20 populations of Guaraní maize landraces through classical and molecular cytogenetic analyses. Our results demonstrate significant intra and inter-populational variation in the percentage, number, size, chromosome position and frequencies of the heterochromatic blocks, which are called knobs. Knob sequence analysis (180-bp and TR-1) did not show significant differences among Guaraní populations. B chromosomes were not detected, and abnormal 10 (AB10) chromosomes were found with low frequency (0.1≥f ≤0.40) in six populations. Our results allowed karyotypic characterization of each analyzed population, defining for the first time the chromosomal constitution of maize germplasm from NEA. The multivariate analysis (PCoA and UPGMA) of karyotype parameters allowed the distinction between two populations groups: the Popcorn and the Floury maize populations. These results are in agreement with previously published microsatellite and morphological/phenological studies. Finally, we compared our karyotype results with those previously reported for NWA and Central Region of South America maize. Our data suggest that there are important differences between maize from NEA and NWA at the karyotype level, supporting the hypothesis that there are two pathways of input of South America maize. Our results also confirm the existence of two centers of diversification of Argentinian native maize, NWA and NEA. This work contributes new knowledge about maize diversity, which is relevant for future plans to improve commercial maize, and for conservation of agrobiodiversity.

Similar Genetic Architecture with Shared and Unique Quantitative Trait Loci for Bacterial Cold Water Disease Resistance in Two Rainbow Trout Breeding Populations

PubMed Central

Vallejo, Roger L.; Liu, Sixin; Gao, Guangtu; Fragomeni, Breno O.; Hernandez, Alvaro G.; Leeds, Timothy D.; Parsons, James E.; Martin, Kyle E.; Evenhuis, Jason P.; Welch, Timothy J.; Wiens, Gregory D.; Palti, Yniv

2017-01-01

Bacterial cold water disease (BCWD) causes significant mortality and economic losses in salmonid aquaculture. In previous studies, we identified moderate-large effect quantitative trait loci (QTL) for BCWD resistance in rainbow trout (Oncorhynchus mykiss). However, the recent availability of a 57 K SNP array and a reference genome assembly have enabled us to conduct genome-wide association studies (GWAS) that overcome several experimental limitations from our previous work. In the current study, we conducted GWAS for BCWD resistance in two rainbow trout breeding populations using two genotyping platforms, the 57 K Affymetrix SNP array and restriction-associated DNA (RAD) sequencing. Overall, we identified 14 moderate-large effect QTL that explained up to 60.8% of the genetic variance in one of the two populations and 27.7% in the other. Four of these QTL were found in both populations explaining a substantial proportion of the variance, although major differences were also detected between the two populations. Our results confirm that BCWD resistance is controlled by the oligogenic inheritance of few moderate-large effect loci and a large-unknown number of loci each having a small effect on BCWD resistance. We detected differences in QTL number and genome location between two GWAS models (weighted single-step GBLUP and Bayes B), which highlights the utility of using different models to uncover QTL. The RAD-SNPs detected a greater number of QTL than the 57 K SNP array in one population, suggesting that the RAD-SNPs may uncover polymorphisms that are more unique and informative for the specific population in which they were discovered. PMID:29109734

Similar Genetic Architecture with Shared and Unique Quantitative Trait Loci for Bacterial Cold Water Disease Resistance in Two Rainbow Trout Breeding Populations.

PubMed

Vallejo, Roger L; Liu, Sixin; Gao, Guangtu; Fragomeni, Breno O; Hernandez, Alvaro G; Leeds, Timothy D; Parsons, James E; Martin, Kyle E; Evenhuis, Jason P; Welch, Timothy J; Wiens, Gregory D; Palti, Yniv

2017-01-01

Bacterial cold water disease (BCWD) causes significant mortality and economic losses in salmonid aquaculture. In previous studies, we identified moderate-large effect quantitative trait loci (QTL) for BCWD resistance in rainbow trout ( Oncorhynchus mykiss ). However, the recent availability of a 57 K SNP array and a reference genome assembly have enabled us to conduct genome-wide association studies (GWAS) that overcome several experimental limitations from our previous work. In the current study, we conducted GWAS for BCWD resistance in two rainbow trout breeding populations using two genotyping platforms, the 57 K Affymetrix SNP array and restriction-associated DNA (RAD) sequencing. Overall, we identified 14 moderate-large effect QTL that explained up to 60.8% of the genetic variance in one of the two populations and 27.7% in the other. Four of these QTL were found in both populations explaining a substantial proportion of the variance, although major differences were also detected between the two populations. Our results confirm that BCWD resistance is controlled by the oligogenic inheritance of few moderate-large effect loci and a large-unknown number of loci each having a small effect on BCWD resistance. We detected differences in QTL number and genome location between two GWAS models (weighted single-step GBLUP and Bayes B), which highlights the utility of using different models to uncover QTL. The RAD-SNPs detected a greater number of QTL than the 57 K SNP array in one population, suggesting that the RAD-SNPs may uncover polymorphisms that are more unique and informative for the specific population in which they were discovered.

A Variable-Instar Climate-Driven Individual Beetle-Based Phenology Model for the Invasive Asian Longhorned Beetle (Coleoptera: Cerambycidae).

PubMed

Trotter, R Talbot; Keena, Melody A

2016-12-01

Efforts to manage and eradicate invasive species can benefit from an improved understanding of the physiology, biology, and behavior of the target species, and ongoing efforts to eradicate the Asian longhorned beetle (Anoplophora glabripennis Motschulsky) highlight the roles this information may play. Here, we present a climate-driven phenology model for A. glabripennis that provides simulated life-tables for populations of individual beetles under variable climatic conditions that takes into account the variable number of instars beetles may undergo as larvae. Phenology parameters in the model are based on a synthesis of published data and studies of A. glabripennis, and the model output was evaluated using a laboratory-reared population maintained under varying temperatures mimicking those typical of Central Park in New York City. The model was stable under variations in population size, simulation length, and the Julian dates used to initiate individual beetles within the population. Comparison of model results with previously published field-based phenology studies in native and invasive populations indicates both this new phenology model, and the previously published heating-degree-day model show good agreement in the prediction of the beginning of the flight season for adults. However, the phenology model described here avoids underpredicting the cumulative emergence of adults through the season, in addition to providing tables of life stages and estimations of voltinism for local populations. This information can play a key role in evaluating risk by predicting the potential for population growth, and may facilitate the optimization of management and eradication efforts. Published by Oxford University Press on behalf of Entomological Society of America 2016. This work is written by US Government employees and is in the public domain in the US.

Variant Discovery and Fine Mapping of Genetic Loci Associated with Blood Pressure Traits in Hispanics and African Americans.

PubMed

Franceschini, Nora; Carty, Cara L; Lu, Yingchang; Tao, Ran; Sung, Yun Ju; Manichaikul, Ani; Haessler, Jeff; Fornage, Myriam; Schwander, Karen; Zubair, Niha; Bien, Stephanie; Hindorff, Lucia A; Guo, Xiuqing; Bielinski, Suzette J; Ehret, Georg; Kaufman, Joel D; Rich, Stephen S; Carlson, Christopher S; Bottinger, Erwin P; North, Kari E; Rao, D C; Chakravarti, Aravinda; Barrett, Paula Q; Loos, Ruth J F; Buyske, Steven; Kooperberg, Charles

2016-01-01

Despite the substantial burden of hypertension in US minority populations, few genetic studies of blood pressure have been conducted in Hispanics and African Americans, and it is unclear whether many of the established loci identified in European-descent populations contribute to blood pressure variation in non-European descent populations. Using the Metabochip array, we sought to characterize the genetic architecture of previously identified blood pressure loci, and identify novel cardiometabolic variants related to systolic and diastolic blood pressure in a multi-ethnic US population including Hispanics (n = 19,706) and African Americans (n = 18,744). Several known blood pressure loci replicated in African Americans and Hispanics. Fourteen variants in three loci (KCNK3, FGF5, ATXN2-SH2B3) were significantly associated with blood pressure in Hispanics. The most significant diastolic blood pressure variant identified in our analysis, rs2586886/KCNK3 (P = 5.2 x 10-9), also replicated in independent Hispanic and European-descent samples. African American and trans-ethnic meta-analysis data identified novel variants in the FGF5, ULK4 and HOXA-EVX1 loci, which have not been previously associated with blood pressure traits. Our identification and independent replication of variants in KCNK3, a gene implicated in primary hyperaldosteronism, as well as a variant in HOTTIP (HOXA-EVX1) suggest that further work to clarify the roles of these genes may be warranted. Overall, our findings suggest that loci identified in European descent populations also contribute to blood pressure variation in diverse populations including Hispanics and African Americans-populations that are understudied for hypertension genetic risk factors.

Consumptive and nonconsumptive effects of cannibalism in fluctuating age-structured populations.

PubMed

Wissinger, Scott A; Whiteman, Howard H; Denoël, Mathieu; Mumford, Miranda L; Aubee, Catherine B

2010-02-01

Theory and empirical studies suggest that cannibalism in age-structured populations can regulate recruitment depending on the intensity of intraspecific competition between cannibals and victims and the nature of the cannibalism window, i.e., which size classes interact as cannibals and victims. Here we report on a series of experiments that quantify that window for age-structured populations of salamander larvae and paedomorphic adults. We determined body size limits on cannibalism in microcosms and then the consumptive and nonconsumptive (injuries, foraging and activity, diet, growth) effects on victims in mesocosms with seminatural levels of habitat complexity and alternative prey. We found that cannibalism by the largest size classes (paedomorphs and > or = age 3+ yr larvae) occurs mainly on young-of-the-year (YOY) victims. Surviving YOY and other small larvae had increased injuries, reduced activity levels, and reduced growth rates in the presence of cannibals. Data on YOY survival in an experiment in which we manipulated the density of paedomorphs combined with historical data on the number of cannibals in natural populations indicate that dominant cohorts of paedomorphs can cause observed recruitment failures. Dietary data indicate that ontogenetic shifts in diet should preclude strong intraspecific competition between YOY and cannibals in this species. Thus our results are consistent with previous empirical and theoretical work that suggests that recruitment regulation by cannibalism is most likely when YOY are vulnerable to cannibalism but have low dietary overlap with cannibals. Understanding the role of cannibalism in regulating recruitment in salamander populations is timely, given the widespread occurrences of amphibian decline. Previous studies have focused on extrinsic (including anthropogenic) factors that affect amphibian population dynamics, whereas the data presented here combined with long-term field observations suggest the potential for intrinsically driven population cycles.

CYTOPLASMIC DNA SYNTHESIS IN AMOEBA PROTEUS

PubMed Central

Rabinovitch, M.; Plaut, W.

1962-01-01

Nucleic acid-containing particles in the cytoplasm of Amoeba proteus (cf. reference 1) were counted after acridine orange staining. The number of particles per ameba was found to be correlated with cell age and size. Fresh daughters had a mean particle number of 5400, whereas predivision amebae contained around 11,000 particles. Amebae from two other strains contained similar particles. The particles were found to be clustered in fasted cells and redispersed after feeding. A marked increase in the particle population was noted in anucleate fragments. These results, together with those previously presented, suggest that the particles multiply intracellularly. Their nature and their relationship to previous work on nucleic acid labeling in Amoeba are discussed. PMID:13972869

Dominant resistance to Bt cotton and minor cross-resistance to Bt toxin Cry2Ab in cotton bollworm from China

PubMed Central

Jin, Lin; Wei, Yiyun; Zhang, Lei; Yang, Yihua; Tabashnik, Bruce E; Wu, Yidong

2013-01-01

Evolution of resistance by insect pests threatens the long-term benefits of transgenic crops that produce insecticidal proteins from Bacillus thuringiensis (Bt). Previous work has detected increases in the frequency of resistance to Bt toxin Cry1Ac in populations of cotton bollworm, Helicoverpa armigera, from northern China where Bt cotton producing Cry1Ac has been grown extensively for more than a decade. Confirming that trend, we report evidence from 2011 showing that the percentage of individuals resistant to a diagnostic concentration of Cry1Ac was significantly higher in two populations from different provinces of northern China (1.4% and 2.3%) compared with previously tested susceptible field populations (0%). We isolated two resistant strains: one from each of the two field-selected populations. Relative to a susceptible strain, the two strains had 460- and 1200-fold resistance to Cry1Ac, respectively. Both strains had dominant resistance to a diagnostic concentration of Cry1Ac in diet and to Bt cotton leaves containing Cry1Ac. Both strains had low, but significant cross-resistance to Cry2Ab (4.2- and 5.9-fold), which is used widely as the second toxin in two-toxin Bt cotton. Compared with resistance in other strains of H. armigera, the resistance in the two strains characterized here may be especially difficult to suppress. PMID:24478804

Economic activities and occupations at high risk for workplace bullying: results from a large-scale cross-sectional survey in the general working population in France.

PubMed

Niedhammer, Isabelle; David, Simone; Degioanni, Stéphanie

2007-02-01

To evaluate the prevalence of workplace bullying in the general working population in France, and explore this prevalence across economic activities and occupations. The studied population consisted of a sample of 3,132 men and 4,562 women of the general working population in the southeast of France. A self-administered anonymous questionnaire included the 45-item inventory of workplace bullying elaborated by Leymann, frequency and duration of bullying, and self-report of being exposed to bullying. Cases of bullying were defined using both Leymann's definition (exposure to at least one form of bullying within the previous 12 months, weekly or more, and for at least 6 months) and self-report of bullying. The 12 month prevalence of workplace bullying was 9% for men and 11% for women. The point prevalence was 7.5% on the day of the survey for men and women, and varied from 3 to 18% according to economic activities and occupations among men. High-risk groups for bullying included activities of services for men, and various categories of associate professionals, and of low levels of white and blue collar workers for men, and government associate professionals for women. This first study on workplace bullying in France showed that around 10% of the population studied, and more women than men, had been exposed to bullying within the last 12 months. This study also found that some economic activities and occupations would be at elevated risk for bullying, pointing out the need to better understand and prevent bullying in these high-risk groups.

Stress in police officers: a study of the origins, prevalence and severity of stress-related symptoms within a county police force.

PubMed

Collins, P A; Gibbs, A C C

2003-06-01

High levels of stress-related illness are causing concern across industry. Against a background of impending legislative moves to try to improve this situation, there is a need to identify key work-related stressors. Police work tends to be regarded as inherently stressful because of the personal risk of exposure to confrontation and violence and the day-to-day involvement in a variety of traumatic incidents. As a result, high levels of stress-related symptoms might be expected in this population. To examine the sources of stress-related symptoms within police officers and measure the prevalence of significant associated mental ill-health. A cross-sectional questionnaire survey of a population of 1206 police officers was performed to assess levels of strain associated with a series of potential home and work related stressors. Participants were then split into low and high scoring groups on the basis of a General Health Questionnaire (GHQ) threshold score in order to identify those stressors most associated with mental ill-health effects. Occupational stressors ranking most highly within the population were not specific to policing, but to organizational issues such as the demands of work impinging upon home life, lack of consultation and communication, lack of control over workload, inadequate support and excess workload in general. The high scoring group constituted 41% of the population and differed significantly from those with low scores in perception of all stressors, ranking both personal and occupational stressors more highly, and from personality constraints appeared significantly more 'stress-prone'. A significant association between gender and mental ill-health was found, with females more likely to score more highly on the GHQ than males. This study confirms previous findings of organizational culture and workload as the key issues in officer stress. Given that the degree of symptomatology appears to be worsening, management action is required. Further research is indicated within the police population into a possible increased susceptibility in female officers.

Modelling of atorvastatin pharmacokinetics and the identification of the effect of a BCRP polymorphism in the Japanese population.

PubMed

Tsamandouras, Nikolaos; Guo, Yingying; Wendling, Thierry; Hall, Stephen; Galetin, Aleksandra; Aarons, Leon

2017-01-01

Ethnicity plays a modulating role in atorvastatin pharmacokinetics (PK), with Asian patients reported to have higher exposure compared with Caucasians. Therefore, it is difficult to safely extrapolate atorvastatin PK data and models across ethnic groups. This work aims to develop a population PK model for atorvastatin and its pharmacologically active metabolites specifically for the Japanese population. Subsequently, it aimed to identify genetic polymorphisms affecting atorvastatin PK in this population. Atorvastatin acid (ATA) and ortho-hydroxy-atorvastatin acid (o-OH-ATA) plasma concentrations, clinical/demographic characteristics and genotypes for 18 (3, 3, 1, 1, 7, 2 and 1 in the ABCB1, ABCG2, CYP3A4, CYP3A5, SLCO1B1, SLCO2B1 and PPARA genes, respectively) genetic polymorphisms were collected from 27 Japanese individuals (taking 10 mg atorvastatin once daily) and analysed using a population PK modelling approach. The population PK model developed (one-compartment for ATA linked through metabolite formation to an additional compartment describing the disposition of o-OH-ATA) accurately described the observed data and the associated population variability. Our analysis suggested that patients carrying one variant allele for the rs2622604 polymorphism (ABCG2) show a 55% (95% confidence interval: 16-131%) increase in atorvastatin oral bioavailability relative to the value in individuals without the variant allele. The current work reports the identification in the Japanese population of a BCRP polymorphism, not previously associated with the PK of any statin, that markedly increases ATA and o-OH-ATA exposure. The model developed may be of clinical importance to guide dosing recommendations tailored specifically for the Japanese.

The well-being of community-dwelling near-centenarians and centenarians in Hong Kong: a qualitative study.

PubMed

Wong, Wai-Ching Paul; Lau, Hi-Po Bobo; Kwok, Chun-Fong Noel; Leung, Yee-Man Angela; Chan, Man-Yee Grace; Chan, Wai-Man; Cheung, Siu-Lan Karen

2014-05-13

Hong Kong has one of the highest life expectancy rankings in the world. The number of centenarians and near-centenarians has been increasing locally and internationally. The relative growth of this population is a topic of immense importance for population and health policy makers. Living long and living well are two overlapping but distinct research topics. We previously conducted a quantitative study on 153 near-centenarians and centenarians to explore a wide range of biopsychosocial correlates of health and "living long". This paper reports a follow-up qualitative study examining the potential correlates of "living well" among near-centenarians and centenarians in Hong Kong. Six cognitively, physically, and psychologically sound community-dwelling elders were purposively recruited from a previous quantitative study. Semi-structured interviews were conducted. Four major themes related to living long and well emerged from the responses of the participants: (a) Positive relations with others, (b) Positive events and happiness, (c) Hope for the future, and (d) Positive life attitude. Specifically, we found that having good interpersonal relationships, possessing a collection of positive life events, and maintaining salutary attitudes towards life are considered as important to psychological well-being by long-lived adults in Hong Kong. Most participants perceived their working life as most important to their life history and retired at very old ages. These findings also shed light on the relationships between health, work, and old age.

Update on imbalanced distribution of endodontists: 1995-2006.

PubMed

Waldman, H Barry; Bruder, George A

2009-05-01

Past studies on the number of endodontists in the United States indicated an imbalanced distribution of private practice endodontic practitioners in most regions, states, counties, and zip code areas of the country. The availability of more recent studies by the American Dental Association (ADA) provides an opportunity to follow up on these previous studies. The 2006 and past ADA surveys on the Distribution of Dentists in the United States, Advanced Dental Education, and Dental Practice were used to evaluate the number of graduates from advanced education programs in endodontics, the changing number and distribution of endodontists, full-time and part-time work patterns, and the income of private practicing endodontists. A gradual increase in the number of graduates from advanced education programs in endodontics is reflected in a continuing increase in the overall number of private practicing endodontists, but with ongoing differences in endodontists-to-population ratios at the regional and state levels. The findings follow previous study results confirming the increasing numbers of endodontists and continuing differences in the endodontists-to-population ratios at both the regional and state levels. Concerns about the distribution of endodontists in the future need to be considered in terms of evolving dental disease patterns, changing demands for services, evolving third-party mechanisms, and the increased number of female practitioners (with fewer reported working hours than their male counterparts).

Experimental strategy for translational studies of organophosphorus pesticide neurotoxicity based on real-world occupational exposures to chlorpyrifos.

PubMed

Lein, Pamela J; Bonner, Matthew R; Farahat, Fayssal M; Olson, James R; Rohlman, Diane S; Fenske, Richard A; Lattal, K Matthew; Lasarev, Michael R; Galvin, Kit; Farahat, Taghreed M; Anger, W Kent

2012-08-01

Translational research is needed to understand and predict the neurotoxic consequences associated with repeated occupational exposures to organophosphorus pesticides (OPs). In this report, we describe a research strategy for identifying biomarkers of OP neurotoxicity, and we characterize pesticide application workers in Egypt's Menoufia Governorate who serve as our anchor human population for developing a parallel animal model with similar exposures and behavioral deficits and for examining the influence of human polymorphisms in cytochrome P450 (CYP) and paraoxonase 1 (PON1) enzymes on OP metabolism and toxicity. This population has previously been shown to have high occupational exposures and to exhibit a broad range of neurobehavioral deficits. In addition to observational studies of work practices in the field, questionnaires on demographics, lifestyle and work practices were administered to 146 Egyptian pesticide application workers applying pesticides to the cotton crop. Survey results indicated that the application workforce uses standard operating procedures and standardized equipment provided by Egypt's Ministry of Agriculture, which provides a workforce with a stable work history. We also found that few workers report using personal protective equipment (PPE), which likely contributes to the relatively high exposures reported in these application workers. In summary, this population provides a unique opportunity for identifying biomarkers of OP-induced neurotoxicity associated with occupational exposure. Copyright © 2012 Elsevier Inc. All rights reserved.

Experimental strategy for translational studies of organophosphorus pesticide neurotoxicity based on real-world occupational exposures to chlorpyrifos

PubMed Central

Lein, Pamela J.; Bonner, Matthew R.; Farahat, Fayssal M.; Olson, James R.; Rohlman, Diane S.; Fenske, Richard A.; Lattal, K. Matthew; Lasarev, Michael R.; Galvin, Kit; Farahat, Taghreed M.; Anger, W. Kent

2012-01-01

Translational research is needed to understand and predict the neurotoxic consequences associated with repeated occupational exposures to organophosphorus pesticides (OPs). In this report, we describe a research strategy for identifying biomarkers of OP neurotoxicity, and we characterize pesticide application workers in Egypt’s Menoufia Governorate who serve as our anchor human population for developing a parallel animal model with similar exposures and behavioral deficits and for examining the influence of human polymorphisms in cytochrome P450 (CYP) and paraoxonase 1 (PON1) enzymes on OP metabolism and toxicity. This population has previously been shown to have high occupational exposures and to exhibit a broad range of neurobehavioral deficits. In addition to observational studies of work practices in the field, questionnaires on demographics, lifestyle and work practices were administered to 146 Egyptian pesticide application workers applying pesticides to the cotton crop. Survey results indicated that the application workforce uses standard operating procedures and standardized equipment provided by Egypt’s Ministry of Agriculture, which provides a workforce with a stable work history. We also found that few workers report using personal protective equipment (PPE), which likely contributes to the relatively high exposures reported in these application workers. In summary, this population provides a unique opportunity for identifying biomarkers of OP-induced neurotoxicity associated with occupational exposure. PMID:22240005

Defining the Diverse Cell Populations Contributing to Lignification in Arabidopsis Stems.

PubMed

Smith, Rebecca A; Schuetz, Mathias; Karlen, Steven D; Bird, David; Tokunaga, Naohito; Sato, Yasushi; Mansfield, Shawn D; Ralph, John; Samuels, A Lacey

2017-06-01

Many land plants evolved tall and sturdy growth habits due to specialized cells with thick lignified cell walls: tracheary elements that function in water transport and fibers that function in structural support. The objective of this study was to define how and when diverse cell populations contribute lignin precursors, monolignols, to secondary cell walls during lignification of the Arabidopsis ( Arabidopsis thaliana ) inflorescence stem. Previous work demonstrated that, when lignin biosynthesis is suppressed in fiber and tracheary element cells with thickened walls, fibers become lignin-depleted while vascular bundles still lignify, suggesting that nonlignifying neighboring xylem cells are contributing to lignification. In this work, we dissect the contributions of different cell types, specifically xylary parenchyma and fiber cells, to lignification of the stem using cell-type-specific promoters to either knock down an essential monolignol biosynthetic gene or to introduce novel monolignol conjugates. Analysis of either reductions in lignin in knockdown lines, or the addition of novel monolignol conjugates, directly identifies the xylary parenchyma and fiber cell populations that contribute to the stem lignification and the developmental timing at which each contribution is most important. © 2017 American Society of Plant Biologists. All Rights Reserved.

We need more empirical investigations and model validation for a better understanding of crime. Comment on "Statistical physics of crime: A review" by M.R. D'Orsogna and M. Perc

NASA Astrophysics Data System (ADS)

Ribeiro, Haroldo V.

2015-03-01

Since the seminal works of Wilson and Kelling [1] in 1982, the "broken windows theory" seems to have been widely accepted among the criminologists and, in fact, empirical findings actually point out that criminals tend to return to previously visited locations. Crime has always been part of the urban society's agenda and has also attracted the attention of scholars from social sciences ever since. Furthermore, over the past six decades the world has experienced a quick and notorious urbanization process: by the eighties the urban population was about 40% of total population, and today more than half (54%) of the world population is urban [2]. The urbanization has brought us many benefits such as better working opportunities and health care, but has also created several problems such as pollution and a considerable rise in the criminal activities. In this context of urban problems, crime deserves a special attention because there is a huge necessity of empirical and mathematical (modeling) investigations which, apart from the natural academic interest, may find direct implications for the organization of our society by improving political decisions and resource allocation.

Atlas warping for brain morphometry

NASA Astrophysics Data System (ADS)

Machado, Alexei M. C.; Gee, James C.

1998-06-01

In this work, we describe an automated approach to morphometry based on spatial normalizations of the data, and demonstrate its application to the analysis of gender differences in the human corpus callosum. The purpose is to describe a population by a reduced and representative set of variables, from which a prior model can be constructed. Our approach is rooted in the assumption that individual anatomies can be considered as quantitative variations on a common underlying qualitative plane. We can therefore imagine that a given individual's anatomy is a warped version of some referential anatomy, also known as an atlas. The spatial warps which transform a labeled atlas into anatomic alignment with a population yield immediate knowledge about organ size and shape in the group. Furthermore, variation within the set of spatial warps is directly related to the anatomic variation among the subjects. Specifically, the shape statistics--mean and variance of the mappings--for the population can be calculated in a special basis, and an eigendecomposition of the variance performed to identify the most significant modes of shape variation. The results obtained with the corpus callosum study confirm the existence of substantial anatomical differences between males and females, as reported in previous experimental work.

[The Brazilian economy in the 80's and its impact on the living conditions of the population].

PubMed

Ometto, A M; Furtuoso, M C; da Silva, M V

1995-10-01

In the 80's the Brazilian economy underwent one of the most severe crises of its history, resulting in the stagnation of the gross national product and inflation rates such as never previously reported. Despite this unfavorable scenario social indicators have presented a positive evolution. This work shows that although the Brazilian family has adopted the over-use of the family work force as a strategy for facing this crisis on the work market, the evolution of both income and poverty in that period were poor. The increase of expenses and the transformation of the forms of implementation of public policy in the health and nutrition areas are shown to be decisive factors in the performance of social indicators.

Novel 384-well population patch clamp electrophysiology assays for Ca2+-activated K+ channels.

PubMed

John, Victoria H; Dale, Tim J; Hollands, Emma C; Chen, Mao Xiang; Partington, Leanne; Downie, David L; Meadows, Helen J; Trezise, Derek J

2007-02-01

Planar array electrophysiology techniques were applied to assays for modulators of recombinant hIK and hSK3 Ca2+-activated K+ channels. In CHO-hIK-expressing cells, under asymmetric K+ gradients, small-molecule channel activators evoked time- and voltage-independent currents characteristic of those previously described by classical patch clamp electrophysiology methods. In single-hole (cell) experiments, the large cell-to-cell heterogeneity in channel expression rendered it difficult to generate activator concentration-response curves. However, in population patch clamp mode, in which signals are averaged from up to 64 cells, well-to-well variation was substantially reduced such that concentration-response curves could be easily constructed. The absolute EC50 values and rank order of potency for a range of activators, including 1-EBIO and DC-EBIO, corresponded well with conventional patch clamp data. Activator responses of hIK and hSK3 channels could be fully and specifically blocked by the selective inhibitors TRAM-34 and apamin, with IC50 values of 0.31 microM and 3 nM, respectively. To demonstrate assay precision and robustness, a test set of 704 compounds was screened in a 384-well format of the hIK assay. All plates had Z' values greater than 0.6, and the statistical cutoff for activity was 8%. Eleven hits (1.6%) were identified from this set, in addition to the randomly spiked wells with known activators. Overall, our findings demonstrate that population patch clamp is a powerful and enabling method for screening Ca2+-activated K+ channels and provides significant advantages over single-cell electrophysiology (IonWorks(HT)) and other previously published approaches. Moreover, this work demonstrates for the 1st time the utility of population patch clamp for ion channel activator assays and for non-voltage-gated ion channels.

Habit Discontinuity, Self-Activation, and the Diminishing Influence of Context Change: Evidence from the UK Understanding Society Survey.

PubMed

Thomas, Gregory Owen; Poortinga, Wouter; Sautkina, Elena

2016-01-01

Repeated behaviours in stable contexts can become automatic habits. Habits are resistant to information-based techniques to change behaviour, but are contextually cued, so a change in behaviour context (e.g., location) weakens habit strength and can facilitate greater consideration of the behaviour. This idea was demonstrated in previous work, whereby people with strong environmental attitudes have lower car use, but only after recently moving home. We examine the habit discontinuity hypothesis by analysing the Understanding Society dataset with 18,053 individuals representative of the UK population, measuring time since moving home, travel mode to work, and strength of environmental attitudes. Results support previous findings where car use is significantly lower among those with stronger environmental views (but only after recently moving home), and in addition, demonstrate a trend where this effects decays as the time since moving home increases. We discuss results in light of moving into a new home being a potential 'window of opportunity' to promote pro-environmental behaviours.

Habit Discontinuity, Self-Activation, and the Diminishing Influence of Context Change: Evidence from the UK Understanding Society Survey

PubMed Central

Thomas, Gregory Owen; Poortinga, Wouter; Sautkina, Elena

2016-01-01

Repeated behaviours in stable contexts can become automatic habits. Habits are resistant to information-based techniques to change behaviour, but are contextually cued, so a change in behaviour context (e.g., location) weakens habit strength and can facilitate greater consideration of the behaviour. This idea was demonstrated in previous work, whereby people with strong environmental attitudes have lower car use, but only after recently moving home. We examine the habit discontinuity hypothesis by analysing the Understanding Society dataset with 18,053 individuals representative of the UK population, measuring time since moving home, travel mode to work, and strength of environmental attitudes. Results support previous findings where car use is significantly lower among those with stronger environmental views (but only after recently moving home), and in addition, demonstrate a trend where this effects decays as the time since moving home increases. We discuss results in light of moving into a new home being a potential ‘window of opportunity’ to promote pro-environmental behaviours. PMID:27120333

Forecasting the impact of transport improvements on commuting and residential choice

NASA Astrophysics Data System (ADS)

Elhorst, J. Paul; Oosterhaven, Jan

2006-03-01

This paper develops a probabilistic, competing-destinations, assignment model that predicts changes in the spatial pattern of the working population as a result of transport improvements. The choice of residence is explained by a new non-parametric model, which represents an alternative to the popular multinominal logit model. Travel times between zones are approximated by a normal distribution function with different mean and variance for each pair of zones, whereas previous models only use average travel times. The model’s forecast error of the spatial distribution of the Dutch working population is 7% when tested on 1998 base-year data. To incorporate endogenous changes in its causal variables, an almost ideal demand system is estimated to explain the choice of transport mode, and a new economic geography inter-industry model (RAEM) is estimated to explain the spatial distribution of employment. In the application, the model is used to forecast the impact of six mutually exclusive Dutch core-periphery railway proposals in the projection year 2020.

Cumulative exposure to shift work and sickness absence: associations in a five-year historic cohort.

PubMed

van Drongelen, Alwin; Boot, Cécile R L; Hlobil, Hynek; van der Beek, Allard J; Smid, Tjabe

2017-01-11

Exposure to shift work has been associated with negative health consequences, although the association between shift work and sickness absence remains unclear. The aim of this study is to investigate associations between cumulative exposure to shift work and sickness absence among ground staff employees of an airline company. This study used data from the MORE (Monitoring Occupational Health Risks in Employees) cohort, which is a 5-year historic cohort. The population of the present study consisted of 7562 ground staff employees. For each employee, work schedules and sickness absence days between 2005 and 2009 were obtained from company records. For the exposure to different shift schedule types and to the cumulative number of night shifts, the association with long-term sickness absence (>7 consecutive sickness absence days) and the number of sickness absence episodes during 2009, was calculated using logistic and Poisson regression analyses. Socio-demographic variables, work-related variables, job classification variables, and previous sickness absence days were regarded as confounders. After adjusting for previous sickness absence and job classification variables, only the group of employees that switched into working in a three-shift schedule, showed a significantly increased risk for long-term sickness absence (OR = 1.31, 95%CI 1.02-1.69). Night shift exposure was not significantly associated with long-term sickness absence. Exposure to shift work was negatively associated with more sickness absence episodes. Employees who were exposed to more than 46 night shifts also showed a lower risk for more sickness absence episodes. Subgroup analyses showed that single employees and employees without children had an increased risk for long-term sickness absence when exposed to a three-shift schedule, and when they had changed between shift schedule types. Cumulative exposure to shift work proved to be negatively associated with more sickness absence episodes, and was not associated with more long-term sickness absence, although selection bias could not be ruled out. Future research should explore the influence of household composition, and take into account both previous sickness absence and psychosocial and physical work factors to obtain a better estimation of the association between shift work and sickness absence.

Are there health effects of harassment in the workplace? A gender-sensitive study of the relationships between work and neck pain.

PubMed

Stock, Susan R; Tissot, France

2012-01-01

The aim of this study was to identify workplace physical and psychosocial risk factors for neck pain among male and female workers and, in particular, to study the relationship between neck pain and intimidation and sexual harassment in the workplace in a representative sample of the Quebec working population. The study sample included 5405 men and 3987 women. In multiple logistic regression analyses, when taking into account individual and other workplace factors, neck pain was significantly associated with intimidation at work among both male (odds ratio (OR) 1.4 (1.01-1.8)) and female workers (OR 1.3 (1.01-1.8)). Among female workers, neck pain was alsosignificantly associated with unwanted sexual attention (OR 1.6 (1.1-2.4)). If confirmed in prospective studies, these results suggest that interventions to prevent harassment in the workplace may help reduce musculoskeletal disorders in the workplace and that workplace programmes to reduce harassment in the workplace should include prevention of sexual harassment. While taking into account relevant personal factors and previously identified workplace physical and psychosocial risk factors, this gender-based study identifies new work exposures associated with neck pain that have not previously been studied, including unwanted sexual attention, intimidation and difficult or tense situations with the public.

Distribution and determinants of maximal physical work capacity of Korean male metal workers.

PubMed

Kang, D; Woo, J H; Shin, Y C

2007-12-01

The distribution of maximal physical work capacity (MPWC) can be used to establish an upper limit for energy expenditure during work (EEwork). If physically demanding work has wearing effects, there will be a negative relationship between MPWC and workload. This study was conducted to investigate the distribution of MPWC among Korean metal workers and to examine the relationship between workload and MPWC. MPWC was estimated with a bicycle ergometer using a submaximal test. Energy expenditure was estimated by measuring heart rates during work. The study subjects were 507 male employees from several metal industries in Korea. They had a lower absolute VO2max than the Caucasian populations described in previous studies. The older workers had a lower physical capacity and a greater overload at work. A negative relationship was found between MPWC and workload across all age groups. Upper limits for EEwork for all age groups and for older age groups are recommended based on the 5th percentile value of MPWC.

Input dependent cell assembly dynamics in a model of the striatal medium spiny neuron network.

PubMed

Ponzi, Adam; Wickens, Jeff

2012-01-01

The striatal medium spiny neuron (MSN) network is sparsely connected with fairly weak GABAergic collaterals receiving an excitatory glutamatergic cortical projection. Peri-stimulus time histograms (PSTH) of MSN population response investigated in various experimental studies display strong firing rate modulations distributed throughout behavioral task epochs. In previous work we have shown by numerical simulation that sparse random networks of inhibitory spiking neurons with characteristics appropriate for UP state MSNs form cell assemblies which fire together coherently in sequences on long behaviorally relevant timescales when the network receives a fixed pattern of constant input excitation. Here we first extend that model to the case where cortical excitation is composed of many independent noisy Poisson processes and demonstrate that cell assembly dynamics is still observed when the input is sufficiently weak. However if cortical excitation strength is increased more regularly firing and completely quiescent cells are found, which depend on the cortical stimulation. Subsequently we further extend previous work to consider what happens when the excitatory input varies as it would when the animal is engaged in behavior. We investigate how sudden switches in excitation interact with network generated patterned activity. We show that sequences of cell assembly activations can be locked to the excitatory input sequence and outline the range of parameters where this behavior is shown. Model cell population PSTH display both stimulus and temporal specificity, with large population firing rate modulations locked to elapsed time from task events. Thus the random network can generate a large diversity of temporally evolving stimulus dependent responses even though the input is fixed between switches. We suggest the MSN network is well suited to the generation of such slow coherent task dependent response which could be utilized by the animal in behavior.

Input Dependent Cell Assembly Dynamics in a Model of the Striatal Medium Spiny Neuron Network

PubMed Central

Ponzi, Adam; Wickens, Jeff

2012-01-01

The striatal medium spiny neuron (MSN) network is sparsely connected with fairly weak GABAergic collaterals receiving an excitatory glutamatergic cortical projection. Peri-stimulus time histograms (PSTH) of MSN population response investigated in various experimental studies display strong firing rate modulations distributed throughout behavioral task epochs. In previous work we have shown by numerical simulation that sparse random networks of inhibitory spiking neurons with characteristics appropriate for UP state MSNs form cell assemblies which fire together coherently in sequences on long behaviorally relevant timescales when the network receives a fixed pattern of constant input excitation. Here we first extend that model to the case where cortical excitation is composed of many independent noisy Poisson processes and demonstrate that cell assembly dynamics is still observed when the input is sufficiently weak. However if cortical excitation strength is increased more regularly firing and completely quiescent cells are found, which depend on the cortical stimulation. Subsequently we further extend previous work to consider what happens when the excitatory input varies as it would when the animal is engaged in behavior. We investigate how sudden switches in excitation interact with network generated patterned activity. We show that sequences of cell assembly activations can be locked to the excitatory input sequence and outline the range of parameters where this behavior is shown. Model cell population PSTH display both stimulus and temporal specificity, with large population firing rate modulations locked to elapsed time from task events. Thus the random network can generate a large diversity of temporally evolving stimulus dependent responses even though the input is fixed between switches. We suggest the MSN network is well suited to the generation of such slow coherent task dependent response which could be utilized by the animal in behavior. PMID:22438838

Genotyping by sequencing resolves shallow population structure to inform conservation of Chinook salmon (Oncorhynchus tshawytscha)

PubMed Central

Larson, Wesley A; Seeb, Lisa W; Everett, Meredith V; Waples, Ryan K; Templin, William D; Seeb, James E

2014-01-01

Recent advances in population genomics have made it possible to detect previously unidentified structure, obtain more accurate estimates of demographic parameters, and explore adaptive divergence, potentially revolutionizing the way genetic data are used to manage wild populations. Here, we identified 10 944 single-nucleotide polymorphisms using restriction-site-associated DNA (RAD) sequencing to explore population structure, demography, and adaptive divergence in five populations of Chinook salmon (Oncorhynchus tshawytscha) from western Alaska. Patterns of population structure were similar to those of past studies, but our ability to assign individuals back to their region of origin was greatly improved (>90% accuracy for all populations). We also calculated effective size with and without removing physically linked loci identified from a linkage map, a novel method for nonmodel organisms. Estimates of effective size were generally above 1000 and were biased downward when physically linked loci were not removed. Outlier tests based on genetic differentiation identified 733 loci and three genomic regions under putative selection. These markers and genomic regions are excellent candidates for future research and can be used to create high-resolution panels for genetic monitoring and population assignment. This work demonstrates the utility of genomic data to inform conservation in highly exploited species with shallow population structure. PMID:24665338

Estimating and modeling the cure fraction in population-based cancer survival analysis.

PubMed

Lambert, Paul C; Thompson, John R; Weston, Claire L; Dickman, Paul W

2007-07-01

In population-based cancer studies, cure is said to occur when the mortality (hazard) rate in the diseased group of individuals returns to the same level as that expected in the general population. The cure fraction (the proportion of patients cured of disease) is of interest to patients and is a useful measure to monitor trends in survival of curable disease. There are 2 main types of cure fraction model, the mixture cure fraction model and the non-mixture cure fraction model, with most previous work concentrating on the mixture cure fraction model. In this paper, we extend the parametric non-mixture cure fraction model to incorporate background mortality, thus providing estimates of the cure fraction in population-based cancer studies. We compare the estimates of relative survival and the cure fraction between the 2 types of model and also investigate the importance of modeling the ancillary parameters in the selected parametric distribution for both types of model.

Global asymptotic stability of plant-seed bank models.

PubMed

Eager, Eric Alan; Rebarber, Richard; Tenhumberg, Brigitte

2014-07-01

Many plant populations have persistent seed banks, which consist of viable seeds that remain dormant in the soil for many years. Seed banks are important for plant population dynamics because they buffer against environmental perturbations and reduce the probability of extinction. Viability of the seeds in the seed bank can depend on the seed's age, hence it is important to keep track of the age distribution of seeds in the seed bank. In this paper we construct a general density-dependent plant-seed bank model where the seed bank is age-structured. We consider density dependence in both seedling establishment and seed production, since previous work has highlighted that overcrowding can suppress both of these processes. Under certain assumptions on the density dependence, we prove that there is a globally stable equilibrium population vector which is independent of the initial state. We derive an analytical formula for the equilibrium population using methods from feedback control theory. We apply these results to a model for the plant species Cirsium palustre and its seed bank.

Balanced cortical microcircuitry for spatial working memory based on corrective feedback control.

PubMed

Lim, Sukbin; Goldman, Mark S

2014-05-14

A hallmark of working memory is the ability to maintain graded representations of both the spatial location and amplitude of a memorized stimulus. Previous work has identified a neural correlate of spatial working memory in the persistent maintenance of spatially specific patterns of neural activity. How such activity is maintained by neocortical circuits remains unknown. Traditional models of working memory maintain analog representations of either the spatial location or the amplitude of a stimulus, but not both. Furthermore, although most previous models require local excitation and lateral inhibition to maintain spatially localized persistent activity stably, the substrate for lateral inhibitory feedback pathways is unclear. Here, we suggest an alternative model for spatial working memory that is capable of maintaining analog representations of both the spatial location and amplitude of a stimulus, and that does not rely on long-range feedback inhibition. The model consists of a functionally columnar network of recurrently connected excitatory and inhibitory neural populations. When excitation and inhibition are balanced in strength but offset in time, drifts in activity trigger spatially specific negative feedback that corrects memory decay. The resulting networks can temporally integrate inputs at any spatial location, are robust against many commonly considered perturbations in network parameters, and, when implemented in a spiking model, generate irregular neural firing characteristic of that observed experimentally during persistent activity. This work suggests balanced excitatory-inhibitory memory circuits implementing corrective negative feedback as a substrate for spatial working memory. Copyright © 2014 the authors 0270-6474/14/346790-17$15.00/0.

Nigerian Immigrant Population in Spain Is Little Sensitized to Living-Related Kidney Donation.

PubMed

Ríos, A; Carrillo, J; López-Navas, A I; Ayala, M A; Garrido, G; Sebastián, M J; Martínez-Alarcón, L; Ramis, G; Hernández, A M; Ramírez, P; Parrilla, P

2018-03-01

The Nigerian population is an emerging group in Spain and in Europe, but their sensitization toward living kidney donation has not been studied. The aim of this work was to analyze the attitude toward related renal donation while alive among the population born in Nigeria resident in Spain. A population older than 15 years born in Nigeria and resident in Spain, stratified by age and sex, was studied with the use of the attitude questionnaire about living kidney donation, "PCID-DVR-Ríos." People were randomly selected based on stratification. African immigration support associations advised on the location of potential respondents. Completion of the questionnaire was anonymous and self-administered. Verbal consent was requested to assist in the study. Statistical methods included Student t test, χ 2 , Fisher exact test, and logistic regression analysis. A total of 179 respondents were included in the study: 70% (n = 125) were in favor of living-related kidney donation, and 30% (n = 54) remained against or undecided. This attitude was associated with different psychosocial factors: marital status (P = .001), having offspring (P = .029), risk assessment of live donation (P < .001), partner's opinion about donation (P < .001), previous relationship with donation and/or transplantation (P < .001), religion (P < .001), and fear of mutilation after donation (P < .001). In the multivariate analysis, the previous relationship with donation and/or transplantation (odds ratio, 8.064) persisted as the main related factor. The Nigerian immigrant population in Spain has a less favorable attitude toward living kidney donation than the native western European and Spanish population. Copyright © 2017 Elsevier Inc. All rights reserved.

Estimating finite-population reproductive numbers in heterogeneous populations.

PubMed

Keegan, Lindsay T; Dushoff, Jonathan

2016-05-21

The basic reproductive number, R0, is one of the most important epidemiological quantities. R0 provides a threshold for elimination and determines when a disease can spread or when a disease will die out. Classically, R0 is calculated assuming an infinite population of identical hosts. Previous work has shown that heterogeneity in the host mixing rate increases R0 in an infinite population. However, it has been suggested that in a finite population, heterogeneity in the mixing rate may actually decrease the finite-population reproductive numbers. Here, we outline a framework for discussing different types of heterogeneity in disease parameters, and how these affect disease spread and control. We calculate "finite-population reproductive numbers" with different types of heterogeneity, and show that in a finite population, heterogeneity has complicated effects on the reproductive number. We find that simple heterogeneity decreases the finite-population reproductive number, whereas heterogeneity in the intrinsic mixing rate (which affects both infectiousness and susceptibility) increases the finite-population reproductive number when R0 is small relative to the size of the population and decreases the finite-population reproductive number when R0 is large relative to the size of the population. Although heterogeneity has complicated effects on the finite-population reproductive numbers, its implications for control are straightforward: when R0 is large relative to the size of the population, heterogeneity decreases the finite-population reproductive numbers, making disease control or elimination easier than predicted by R0. Copyright © 2016 Elsevier Ltd. All rights reserved.

Genetic evidence for adaptation-driven incipient speciation of Drosophila melanogaster along a microclimatic contrast in “Evolution Canyon,” Israel

PubMed Central

Michalak, Pawel; Minkov, Irina; Helin, Amanda; Lerman, Daniel N.; Bettencourt, Brian R.; Feder, Martin E.; Korol, Abraham B.; Nevo, Eviatar

2001-01-01

Substantial genetic differentiation, as great as among species, exists between populations of Drosophila melanogaster inhabiting opposite slopes of a small canyon. Previous work has shown that prezygotic sexual isolation and numerous differences in stress-related phenotypes have evolved between D. melanogaster populations in “Evolution Canyon,” Israel, in which slopes 100–400 m apart differ dramatically in aridity, solar radiation, and associated vegetation. Because the canyon's width is well within flies' dispersal capabilities, we examined genetic changes associated with local adaptation and incipient speciation in the absence of geographical isolation. Here we report remarkable genetic differentiation of microsatellites and divergence in the regulatory region of hsp70Ba which encodes the major inducible heat shock protein of Drosophila, in the two populations. Additionally, an analysis of microsatellites suggests a limited exchange of migrants and lack of recent population bottlenecks. We hypothesize that adaptation to the contrasting microclimates overwhelms gene flow and is responsible for the genetic and phenotypic divergence between the populations. PMID:11687637

Risky behavior and its effect on survival: snowshoe hare behavior under varying moonlight conditions

USGS Publications Warehouse

Gigliotti, Laura C.; Diefenbach, Duane R.

2018-01-01

Predation and predation risk can exert strong influences on the behavior of prey species. However, risk avoidance behaviors may vary among populations of the same species. We studied a population of snowshoe hares (Lepus americanus) near the southern edge of their range, in Pennsylvania. This population occupies different habitat types, experiences different environmental conditions, and are exposed to different predator species and densities than northern hare populations; therefore, they might exhibit differences in risk avoidance behaviors. We analyzed hare survival, movement rates, and habitat use under different levels of predation risk, as indexed by moonlight. Similar to previous work, we found snowshoe hare survival decreased with increased moon illumination during the winter, but we found differences in behavioral responses to increased predation risk. We found that snowshoe hares did not reduce movement rates during high‐risk nights, but instead found that hares selected areas with denser canopy cover, compared to low‐risk nights. We suggest that behavioral plasticity in response to predation risk allows populations of the same species to respond to localized conditions.

Inferring Demographic History Using Two-Locus Statistics.

PubMed

Ragsdale, Aaron P; Gutenkunst, Ryan N

2017-06-01

Population demographic history may be learned from contemporary genetic variation data. Methods based on aggregating the statistics of many single loci into an allele frequency spectrum (AFS) have proven powerful, but such methods ignore potentially informative patterns of linkage disequilibrium (LD) between neighboring loci. To leverage such patterns, we developed a composite-likelihood framework for inferring demographic history from aggregated statistics of pairs of loci. Using this framework, we show that two-locus statistics are more sensitive to demographic history than single-locus statistics such as the AFS. In particular, two-locus statistics escape the notorious confounding of depth and duration of a bottleneck, and they provide a means to estimate effective population size based on the recombination rather than mutation rate. We applied our approach to a Zambian population of Drosophila melanogaster Notably, using both single- and two-locus statistics, we inferred a substantially lower ancestral effective population size than previous works and did not infer a bottleneck history. Together, our results demonstrate the broad potential for two-locus statistics to enable powerful population genetic inference. Copyright © 2017 by the Genetics Society of America.

The cultural implications of growth: Modeling nonlinear interaction of trait selection and population dynamics

NASA Astrophysics Data System (ADS)

Antoci, Angelo; Galeotti, Marcello; Russu, Paolo; Luigi Sacco, Pier

2018-05-01

In this paper, we study a nonlinear model of the interaction between trait selection and population dynamics, building on previous work of Ghirlanda et al. [Theor. Popul. Biol. 77, 181-188 (2010)] and Antoci et al. [Commun. Nonlinear Sci. Numer. Simul. 58, 92-106 (2018)]. We establish some basic properties of the model dynamics and present some simulations of the fine-grained structure of alternative dynamic regimes for chosen combinations of parameters. The role of the parameters that govern the reinforcement/corruption of maladaptive vs. adaptive traits is of special importance in determining the model's dynamic evolution. The main implication of this result is the need to pay special attention to the structural forces that may favor the emergence and consolidation of maladaptive traits in contemporary socio-economies, as it is the case, for example, for the stimulation of dysfunctional consumption habits and lifestyles in the pursuit of short-term profits.

The cultural implications of growth: Modeling nonlinear interaction of trait selection and population dynamics.

PubMed

Antoci, Angelo; Galeotti, Marcello; Russu, Paolo; Luigi Sacco, Pier

2018-05-01

In this paper, we study a nonlinear model of the interaction between trait selection and population dynamics, building on previous work of Ghirlanda et al. [Theor. Popul. Biol. 77, 181-188 (2010)] and Antoci et al. [Commun. Nonlinear Sci. Numer. Simul. 58, 92-106 (2018)]. We establish some basic properties of the model dynamics and present some simulations of the fine-grained structure of alternative dynamic regimes for chosen combinations of parameters. The role of the parameters that govern the reinforcement/corruption of maladaptive vs. adaptive traits is of special importance in determining the model's dynamic evolution. The main implication of this result is the need to pay special attention to the structural forces that may favor the emergence and consolidation of maladaptive traits in contemporary socio-economies, as it is the case, for example, for the stimulation of dysfunctional consumption habits and lifestyles in the pursuit of short-term profits.

Presidential Address National Academy of Neuropsychology Conference Boston 2017.

PubMed

Meyers, John E

2018-05-05

This presidential address attempts to predict the future directions of neuropsychology. Predicting the future is always a difficult thing. By examining population trends such as aging and demographics, a clearer picture becomes visible. The population is getting older and more ethnically diverse. Also, examination of the spending trends in health care indicates that neuropsychology needs to be able to adapt to working with larger population-based patient care as well as individual patient care. Shifts in the demographics of neuropsychology, in that the profession previously was 70% male dominate and now is >70% female dominant are also discussed. Trends in NAN's speaker and leader demographics are examined as well as the need to stay current in the trends and latest neuropsychological research lest we become dinosaurs in the next 5-10 years. Recommendations for new neuropsychologists and post-doctoral fellows are also presented.

Deadly heat waves projected in the densely populated agricultural regions of South Asia.

PubMed

Im, Eun-Soon; Pal, Jeremy S; Eltahir, Elfatih A B

2017-08-01

The risk associated with any climate change impact reflects intensity of natural hazard and level of human vulnerability. Previous work has shown that a wet-bulb temperature of 35°C can be considered an upper limit on human survivability. On the basis of an ensemble of high-resolution climate change simulations, we project that extremes of wet-bulb temperature in South Asia are likely to approach and, in a few locations, exceed this critical threshold by the late 21st century under the business-as-usual scenario of future greenhouse gas emissions. The most intense hazard from extreme future heat waves is concentrated around densely populated agricultural regions of the Ganges and Indus river basins. Climate change, without mitigation, presents a serious and unique risk in South Asia, a region inhabited by about one-fifth of the global human population, due to an unprecedented combination of severe natural hazard and acute vulnerability.

Health shocks adversely impact participation in the labour force in a working age population: a longitudinal analysis.

PubMed

Carter, Kristie N; Gunasekara, Fiona Imlach; Blakely, Tony; Richardson, Ken

2013-06-01

It is well understood that health affects labour force participation (LFP). However, much of the published research has been on older (retiring age) populations and using subjective health measures. This paper aims to assess the impact of an objective measure of 'health shock' (cancer registration or hospitalisation) on LFP in a working age population using longitudinal panel study data and fixed effect regression analyses. Seven waves of data from 2002-09 from the longitudinal Survey of Family, Income and Employment (SoFIE) were used, including working aged individuals who consented to have their survey information linked to health records (n=6,780). Fixed effect conditional logistic regression was used to model the impact of health shocks (hospitalisation or cancer registration) in the previous year on labour force participation at date of annual interview. Models were stratified by gender, age group (25-39 years, 40-54 years) and gender by age group. A health shock was associated with a significantly increased risk of subsequent non-participation in the labour force (odds ratio 1.54, 95%CI 1.30-1.82). Although interactions of age, sex and age by sex with health shock were not statistically significant, the association was largest in younger men and women. Using an objective measure of health, we have shown that a health shock adversely affects subsequent labour force participation. There are a number of policy and practice implications relating to support for working age people who have hospitalisations. © 2013 The Authors. ANZJPH © 2013 Public Health Association of Australia.

[Prevalence of cardiovascular risk factors in the Spanish working population].

PubMed

Sánchez-Chaparro, Miguel A; Román-García, Javier; Calvo-Bonacho, Eva; Gómez-Larios, Tomás; Fernández-Meseguer, Ana; Sáinz-Gutiérrez, Juan C; Cabrera-Sierra, Martha; García-García, Angel; Rueda-Vicente, Juan; Gálvez-Moraleda, Adolfo; González-Quintela, Arturo

2006-05-01

The routine medical check-up provides a good opportunity for screening workers early for cardiovascular risk factors. The aim of the present study was to investigate the prevalence of cardiovascular risk factors in the Spanish working population. The study included 216 914 working people (mean age 36.4 years, range 16-74 years, 73.1% male) undergoing routine medical check-up, which involved a structured questionnaire, physical examination, and standard serum biochemical analysis. Cardiovascular disease had been diagnosed previously in 0.7% of workers, hypertension in 6.2%, diabetes in 1.2%, and dyslipidemia in 8.9%. Routine check-up showed that 49.3% (51.3% of males and 43.8% of females) were smokers, 22.1% (27.0% of males and 8.8% of females) had high blood pressure (< or =140/90 mm Hg), 15.5% (18.3% of males and 13.3% of females) were obese (body mass index > or =30), 6.2% (7.8% of males and 1.9% of females) were hyperglycemic (blood glucose >110 mg/dL), and 64.2% had dyslipidemia (total cholesterol > or =200 mg/dL, LDL cholesterol > or =160 mg/dL, triglycerides > or =200 mg/dL, or HDL cholesterol < 40 mg/dL in males or < 50 mg/dL in females). When compared with workers in the service sector and after adjustment for potential confounders, workers in manufacturing, and particularly those in construction, had higher prevalences of both high blood pressure and smoking. The prevalence of cardiovascular risk factors in the Spanish working population is high, particularly in males and in certain types of employment.

Early return to work following open carpal tunnel decompression in lamb freezing workers.

PubMed

Wyatt, M C; Veale, G A

2008-08-01

Carpal tunnel syndrome is common at the largest lamb processing plant in the world, especially in new lamb boners. The purpose of this study was to establish the incidence and whether expeditious return to work following open carpal tunnel decompression was possible. Two hundred patients with a neurophysiologically confirmed diagnosis underwent surgery between 2002 and 2006. One hundred and eighty-seven patients were assessed retrospectively and 13 prospectively. The incidence in new lamb boners was 10% in their first season. On average, workers commenced rehabilitation at 11 days post-operatively and full duties at 29 days post-operatively with minimal further time off taken. Ninety percent returned to their previous role. By 8 weeks in the prospective group visual analogue pain scores had improved from 8.75 to 2.0 (P<0.01) and Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) scores had improved from 140 points to 68 (P<0.01). Grip/pinch testing, static two-point discrimination scores and complication rates were comparable with previous studies. This study provides good evidence that coordinated, early rehabilitation and return to work is effective in a high-demand population.

New low back pain in nurses: work activities, work stress and sedentary lifestyle.

PubMed

Yip, Vera Yin Bing

2004-05-01

Low back pain is common among nurses. Previous studies have shown that the risk of low back pain increases rapidly with greater amounts of physical work and psychological stress, but is inversely related to leisure activities. However, these previous studies were predominantly retrospective in design and not many took account of three factors simultaneously. This 12-month prospective study examined the relationships between work activities, work stress, sedentary lifestyle and new low back pain. A total of 144 nurses from six Hong Kong district hospitals completed a face-to-face baseline interview, which was followed-up by a telephone interview. The main study measures were demographic characteristics, work activities, work stress, physical leisure activities and the nature of new low back pain during the 12-month follow-up period. Level of work stress, quality of relationships at work, level of enjoyment experienced at work, and work satisfaction were self-reported. Fifty-six (38.9%) nurses reported experiencing new low back pain. Sedentary leisure time activity was not associated with new low back pain. Being comparatively new on a ward (adjusted relative risk 2.90), working in bending postures (adjusted relative risk 2.76) and poor work relationships with colleagues (adjusted relative risk 2.52) were independent predictors of new low back pain. The findings of this study suggest that low back pain is a common problem in the population of nurses in Hong Kong. Being comparatively new on a ward, bending frequently during work and having poor work relationships with colleagues are independent predictors of new low back pain. Training for high-risk work activities and ergonomic assessment of awkward work postures are essential. Moreover, relaxation and team-building workshops for nurses, especially those who are less experienced in the type of work on their current ward, are recommended.

Cytoplasmic DNA synthesis in Amoeba proteus. II. On the behavior and possible nature of the DNA-containing elements.

PubMed

RABINOVITCH, M; PLAUT, W

1962-12-01

Nucleic acid-containing particles in the cytoplasm of Amoeba proteus (cf. reference 1) were counted after acridine orange staining. The number of particles per ameba was found to be correlated with cell age and size. Fresh daughters had a mean particle number of 5400, whereas predivision amebae contained around 11,000 particles. Amebae from two other strains contained similar particles. The particles were found to be clustered in fasted cells and redispersed after feeding. A marked increase in the particle population was noted in anucleate fragments. These results, together with those previously presented, suggest that the particles multiply intracellularly. Their nature and their relationship to previous work on nucleic acid labeling in Amoeba are discussed.

Epidemics on adaptive networks with geometric constraints

NASA Astrophysics Data System (ADS)

Shaw, Leah; Schwartz, Ira

2008-03-01

When a population is faced with an epidemic outbreak, individuals may modify their social behavior to avoid exposure to the disease. Recent work has considered models in which the contact network is rewired dynamically so that susceptibles avoid contact with infectives. We consider extensions in which the rewiring is subject to constraints that preserve key properties of the social network structure. Constraining to a fixed degree distribution destroys previously observed bistable behavior. The most effective rewiring strategy is found to depend on the spreading rate.

Isolation, Identification and Characterization of Yeasts from Fermented Goat Milk of the Yaghnob Valley in Tajikistan

PubMed Central

Qvirist, Linnea A.; De Filippo, Carlotta; Strati, Francesco; Stefanini, Irene; Sordo, Maddalena; Andlid, Thomas; Felis, Giovanna E.; Mattarelli, Paola; Cavalieri, Duccio

2016-01-01

The geographically isolated region of the Yaghnob Valley, Tajikistan, has allowed its inhabitants to maintain a unique culture and lifestyle. Their fermented goat milk constitutes one of the staple foods for the Yaghnob population, and is produced by backslopping, i.e., using the previous fermentation batch to inoculate the new one. This study addresses the yeast composition of the fermented milk, assessing genotypic, and phenotypic properties. The 52 isolates included in this study revealed small species diversity, belonging to Kluyveromyces marxianus, Pichia fermentans, Saccharomyces cerevisiae, and one Kazachstania unispora. The K. marxianus strains showed two different genotypes, one of which never described previously. The two genetically different groups also differed significantly in several phenotypic characteristics, such as tolerance toward high temperatures, low pH, and presence of acid. Microsatellite analysis of the S. cerevisiae strains from this study, compared to 350 previously described strains, attributed the Yaghnobi S. cerevisiae to two different ancestry origins, both distinct from the wine and beer strains, and similar to strains isolated from human and insects feces, suggesting a peculiar origin of these strains, and the existence of a gut reservoir for S. cerevisiae. Our work constitutes a foundation for strain selection for future applications as starter cultures in food fermentations. This work is the first ever on yeast diversity from fermented milk of the previously unexplored area of the Yaghnob Valley. PMID:27857705

Relationship between long working hours and depression in two working populations: a structural equation model approach.

PubMed

Amagasa, Takashi; Nakayama, Takeo

2012-07-01

To test the hypothesis that relationship reported between long working hours and depression was inconsistent in previous studies because job demand was treated as a confounder. Structural equation modeling was used to construct five models, using work-related factors and depressive mood scale obtained from 218 clerical workers, to test for goodness of fit and was externally validated with data obtained from 1160 sales workers. Multiple logistic regression analysis was also performed. The model that showed that long working hours increased depression risk when job demand was regarded as an intermediate variable was the best fitted model (goodness-of-fit index/root-mean-square error of approximation: 0.981 to 0.996/0.042 to 0.044). The odds ratio for depression risk with work that was high demand and 60 hours or more per week was estimated at 2 to 4 versus work that was low demand and less than 60 hours per week. Long working hours increased depression risk, with job demand being an intermediate variable.

Increasing neonicotinoid use and the declining butterfly fauna of lowland California

USGS Publications Warehouse

Forister, Matthew L.; Cousens, Bruce; Harrison, Joshua G.; Anderson, Kayce; Thorne, James H.; Waetjen, Dave; Nice, Chris C.; De Parsia, Matthew; Hladik, Michelle; Meese, Robert; van Vliet, Heidi; Shapiro, Arthur M.

2016-01-01

The butterfly fauna of lowland Northern California has exhibited a marked decline in recent years that previous studies have attributed in part to altered climatic conditions and changes in land use. Here, we ask if a shift in insecticide use towards neonicotinoids is associated with butterfly declines at four sites in the region that have been monitored for four decades. A negative association between butterfly populations and increasing neonicotinoid application is detectable while controlling for land use and other factors, and appears to be more severe for smaller-bodied species. These results suggest that neonicotinoids could influence non-target insect populations occurring in proximity to application locations, and highlights the need for mechanistic work to complement long-term observational data.

The prevalence of silicosis in Orange Free State gold miners.

PubMed

Cowie, R L; van Schalkwyk, M G

1987-01-01

The prevalence of silicosis in the migrant laborer in the South African, Orange Free State gold mines has not previously been estimated. Two methods were used to estimate the prevalence of silicosis in this population. The two techniques are described. The difference between the two estimates illustrates the difficulty of epidemiologic studies in this type of working population. It is noted that the highest estimate of 138 cases per 10,000 workers is certainly less than the true prevalence of the disorder. The use of routine miniature (100-mm) chest radiographs for the detection of silicosis was validated through comparison with normal size (125-kV radiographs and through analysis of the consistency of reading of second miniature films from the same subjects.

Beyond Population and Environment: Household Life Cycle Demography and Land Use Allocation among Small Farm Colonists in the Amazon

NASA Technical Reports Server (NTRS)

Perz, Stephen G.; Walker, Robert T.; Caldas, Marcellus M.

2006-01-01

Most research featuring demographic factors in environmental change has focused on processes operating at the level of national or global populations. This paper focuses on household-level demographic life cycles among colonists in the Amazon, and evaluates the impacts on land use allocation. The analysis goes beyond prior research by including a broader suite of demographic variables, and by simultaneously assessing their impacts on multiple land uses with different economic and ecological implications. We estimate a system of structural equations that accounts for endogeneity among land uses, and the findings indicate stronger demographic effects than previous work. These findings bear implications for modeling land use, and the place of demography in environmental research.

PCB residues in the adipose tissue of the population of Barcelona (Spain)

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

Gomez-Catalan, J.; Sabroso, M.; To-Figueras, J.

1991-10-01

Polychlorinated biphenyls (PCBs) are a class of aryl halides widely distributed in the environment. Although production has virtually ceased, and most industrial applications (capacitors, transformers, hydraulic fluids, lubricants, etc) are severely restricted, they are one of the most ubiquitous and persistent environmental pollutants. Several toxic effects caused by PCBs have been described including: liver enlargement, hepatomegalocytosis, acne, lymphoid atrophy, immunosuppression, tumor promotion, porphyria. This work continues the authors' previous reports about organochlorine residues in human tissues of some Spanish populations, that showed high levels of some residues, specially of hexachlorobenzene (HCB). PCBs pattern and concentration in the adipose tissue ofmore » the inhabitants of an urban and industrial area (Barcelona) were determined.« less

Genomic copy number variations in three Southeast Asian populations.

PubMed

Ku, Chee-Seng; Pawitan, Yudi; Sim, Xueling; Ong, Rick T H; Seielstad, Mark; Lee, Edmund J D; Teo, Yik-Ying; Chia, Kee-Seng; Salim, Agus

2010-07-01

Research on the role of copy number variations (CNVs) in the genetic risk of diseases in Asian populations has been hampered by a relative lack of reference CNV maps for Asian populations outside the East Asians. In this article, we report the population characteristics of CNVs in Chinese, Malay, and Asian Indian populations in Singapore. Using the Illumina Human 1M Beadchip array, we identify 1,174 CNV loci in these populations that corroborated with findings when the same samples were typed on the Affymetrix 6.0 platform. We identify 441 novel loci not previously reported in the Database of Genomic Variations (DGV). We observe a considerable number of loci that span all three populations and were previously unreported, as well as population-specific loci that are quite common in the respective populations. From this we observe the distribution of CNVs in the Asian Indian population to be considerably different from the Chinese and Malay populations. About half of the deletion loci and three-quarters of duplication loci overlap UCSC genes. Tens of loci show population differentiation and overlap with genes previously known to be associated with genetic risk of diseases. One of these loci is the CYP2A6 deletion, previously linked to reduced susceptibility to lung cancer. (c) 2010 Wiley-Liss, Inc.

Segregating polymorphisms of FOXP2 are associated with measures of inner speech, speech fluency and strength of handedness in a healthy population.

PubMed

Crespi, Bernard; Read, Silven; Hurd, Peter

2017-10-01

We genotyped a healthy population for three haplotype-tagging FOXP2 SNPs, and tested for associations of these SNPs with strength of handedness and questionnaire-based metrics of inner speech characteristics (ISP) and speech fluency (FLU), as derived from the Schizotypal Personality Questionnaire-BR. Levels of mixed-handedness were positively correlated with ISP and FLU, supporting prior work on these two domains. Genotype for rs7799109, a SNP previously linked with lateralization of left frontal regions underlying language, was associated with degree of mixed handedness and with scores for ISP and FLU phenotypes. Genotype of rs1456031, which has previously been linked with auditory hallucinations, was also associated with ISP phenotypes. These results provide evidence that FOXP2 SNPs influence aspects of human inner speech and fluency that are related to lateralized phenotypes, and suggest that the evolution of human language, as mediated by the adaptive evolution of FOXP2, involved features of inner speech. Copyright © 2017 Elsevier Inc. All rights reserved.

Cohabitation among older adults: a national portrait.

PubMed

Brown, Susan L; Lee, Gary R; Bulanda, Jennifer Roebuck

2006-03-01

Older adults are increasingly likely to experience cohabitation, or living together unmarried in an intimate, heterosexual union. In order to begin building a conceptual framework, we provide a descriptive portrait of older adult cohabitors, emphasizing how they compare to older remarrieds and unpartnereds. We used data from both Census 2000 and the 1998 Health and Retirement Study ( HRS; Health and Retirement Study, 1998) to estimate the size and composition of the cohabiting population aged 51 and older. Also, using HRS data, we estimated multinomial logistic regression models to identify the correlates associated with cohabitation and remarriage (vs being unpartnered) among women and men who were previously married. More than 1 million older adults, composing 4% of the unmarried population, currently cohabit. About 90% of these individuals were previously married. We identify significant differences among cohabitors, remarrieds, and unpartnereds across several dimensions, including sociodemographic characteristics, economic resources, physical health, and social relationships. Cohabitors appear to be more disadvantaged than remarrieds, and this is especially evident for women. Older cohabitors differ from individuals of other marital statuses, and therefore future work on marital status should explicitly incorporate cohabitation.

Alcohol dependence and criminal behavior: preliminary results of an association study of environmental and genetic factors in an Italian male population.

PubMed

Terranova, Claudio; Tucci, Marianna; Sartore, Daniela; Cavarzeran, Fabiano; Barzon, Luisa; Palù, Giorgio; Ferrara, Santo D

2012-09-01

The aim of this study is to propose an innovative approach evaluating the connection between alcohol use disorders and criminal behavior. The research, structured as a case-control study, was based on the analysis of environmental (social variables) and genetic factors (single nucleotide polymorphisms of glutamic acid decarboxylase) in a population (N = 173) of Italian alcohol-dependent men. Group 1 (N = 47, convicted subjects) was compared with Group 2 (N = 126, no previous criminal conduct). Grade repetition, work problems, and drug problems were statistically associated with criminal behavior. Having daily family meals together and having children were inversely related to convictions. The genotype distribution of the two groups was similar. The association between environmental factors and antisocial behavior confirms previous findings in the literature. The lack of genetic association does not exclude the role of the gamma-aminobutyric acid (GABA) system in determining antisocial behavior; further studies with larger samples are needed, together with investigation of other components of the GABA pathway. © 2012 American Academy of Forensic Sciences.

Modeling of diffusive plasmas in local thermodynamic equilibrium with integral constraints: application to mercury-free high pressure discharge lamp mixtures

NASA Astrophysics Data System (ADS)

Janssen, J. F. J.; Suijker, J. L. G.; Peerenboom, K. S. C.; van Dijk, J.

2017-03-01

The mercury free lamp model previously discussed in Gnybida et al (2014 J. Phys. D: Appl. Phys. 47 125201) did not account for self-consistent diffusion and only included two molecular transitions. In this paper we apply, for the first time, a self-consistent diffusion algorithm that features (1) species/mass conservation up to machine accuracy and (2) an arbitrary mix of integral (total mass) and local (cold spot) constraints on the composition. Another advantage of this model is that the total pressure of the gas is calculated self consistently. Therefore, the usage of a predetermined pressure is no longer required. Additionally, the number of association processes has been increased from 2 to 6. The population as a function of interatomic separation determines the spectrum of the emitted continuum radiation. Previously, this population was calculated using the limit of low densities. In this work an expression is used that removes this limitation. The result of these improvements is that the agreement between the simulated and measured spectra has improved considerably.

Referrals to the Glasgow sheriff court liaison scheme since the introduction of referral criteria.

PubMed

Orr, Eilidh M; Baker, Melanie; Ramsay, Louise

2007-10-01

This study is an audit of a court liaison scheme operating in Glasgow sheriff court. It represents a follow-on of previous work after the introduction of referral criteria to delineate more closely the appropriate population to be seen. Results were compared with the previous audit. The total number of referrals decreased by 66%, however, the proportion with a psychotic illness increased to 33%. A high referral rate of prisoners with addictions continued, although the service was not primarily designed for them. Fewer patients with no psychiatric diagnosis were referred to the scheme. Outcomes were, however, similar with approximately the same admission rate to hospital. The introduction of criteria appears to have reduced the numbers of inappropriate referrals without excluding the population with serious mental disorder. The introduction of referral criteria seems to have been beneficial to the scheme. The scheme has since changed again and so there may be benefit for a further audit to monitor the continuing appropriateness of referrals. The provision of specific interventions targeting prisoners with addictions is also supported by this audit.

Early Predictors of Occupational Back Re-Injury: Results from a Prospective Study of Workers in Washington State

PubMed Central

Keeney, Benjamin J.; Turner, Judith A.; Fulton-Kehoe, Deborah; Wickizer, Thomas M.; Chan, Kwun Chuen Gary; Franklin, Gary M.

2014-01-01

Study Design Prospective population-based cohort study Objective To identify early predictors of self-reported occupational back re-injury within 1 year after work-related back injury Summary of Background Data Back injuries are the costliest and most prevalent disabling occupational injuries in the United States. A substantial proportion of workers with back injuries have re-injuries after returning to work, yet there are few studies of risk factors for occupational back re-injuries. Methods We aimed to identify the incidence and early (in the claim) predictors of self-reported back re-injury by approximately 1 year after the index injury among Washington State workers with new work disability claims for back injuries. The Washington Workers’ Compensation Disability Risk Identification Study Cohort (D-RISC) provided a large, population-based sample with information on variables in seven domains: sociodemographic, employment-related, pain and function, clinical status, health care, health behavior, and psychological. We conducted telephone interviews with workers 3 weeks and 1 year after submission of a time-loss claim for the injury. We first identified predictors (p-values < 0.10) of self-reported re-injury within 1 year in bivariate analyses. Those variables were then included in a multivariate logistic regression model predicting occupational back re-injury. Results 290 (25.8%) of 1,123 (70.0% response rate) workers who completed the one-year follow-up interview and had returned to work reported having re-injured their back at work. Baseline variables significantly associated with re-injury (p-value < 0.05) in the multivariate model included male gender, constant whole body vibration at work, a history of previous similar injury, 4 or more previous claims of any type, possessing health insurance, and high fear-avoidance scores. Baseline obesity was associated with reduced odds of re-injury. No other employment-related or psychological variables were significant. Conclusion One-fourth of workers who received work disability compensation for a back injury self-reported re-injury after returning to work. Baseline variables in multiple domains predicted occupational back re-injury. Increased knowledge of early risk factors for re-injury may help lead to interventions, such as efforts to reduce fear-avoidance and graded activity to promote recovery, effective in lowering the risk of re-injury. PMID:22772568

Variation in the local population dynamics of the short-lived Opuntia macrorhiza (Cactaceae).

PubMed

Haridas, C V; Keeler, Kathleen H; Tenhumberg, Brigitte

2015-03-01

Spatiotemporal variation in demographic rates can have profound effects for population persistence, especially for dispersal-limited species living in fragmented landscapes. Long-term studies of plants in such habitats help with understanding the impacts of fragmentation on population persistence but such studies are rare. In this work, we reanalyzed demographic data from seven years of the short-lived cactus Opuntia macrorhiza var. macrorhiza at five plots in Boulder, Colorado. Previous work combining data from all years and all plots predicted a stable population (deterministic log lamda approximately 0). This approach assumed that all five plots were part of a single population. Since the plots were located in a suburban-agricultural interface separated by highways, grazing lands, and other barriers, and O. macrorhiza is likely dispersal limited, we analyzed the dynamics of each plot separately using stochastic matrix models assuming each plot represented a separate population. We found that the stochastic population growth rate log lamdaS varied widely between populations (log lamdaS = 0.1497, 0.0774, -0.0230, -0.2576, -0.4989). The three populations with the highest growth rates were located close together in space, while the two most isolated populations had the lowest growth rates suggesting that dispersal between populations is critical for the population viability of O. macrorhiza. With one exception, both our prospective (stochastic elasticity) and retrospective (stochastic life table response experiments) analysis suggested that means of stasis and growth, especially of smaller plants, were most important for population growth rate. This is surprising because recruitment is typically the most important vital rate in a short-lived species such as O. macrorhiza. We found that elasticity to the variance was mostly negligible, suggesting that O. macrorhiza populations are buffered against large temporal variation. Finally, single-year elasticities to means of transitions to the smallest stage (mostly due to reproduction) and growth differed considerably from their long-term elasticities. It is important to be aware of this difference when using models to predict the effect of manipulating plant vital rates within the time frame of typical plant demographic studies.

Analysis of bacterial genomes from an evolution experiment with horizontal gene transfer shows that recombination can sometimes overwhelm selection

PubMed Central

2018-01-01

Few experimental studies have examined the role that sexual recombination plays in bacterial evolution, including the effects of horizontal gene transfer on genome structure. To address this limitation, we analyzed genomes from an experiment in which Escherichia coli K-12 Hfr (high frequency recombination) donors were periodically introduced into 12 evolving populations of E. coli B and allowed to conjugate repeatedly over the course of 1000 generations. Previous analyses of the evolved strains from this experiment showed that recombination did not accelerate adaptation, despite increasing genetic variation relative to asexual controls. However, the resolution in that previous work was limited to only a few genetic markers. We sought to clarify and understand these puzzling results by sequencing complete genomes from each population. The effects of recombination were highly variable: one lineage was mostly derived from the donors, while another acquired almost no donor DNA. In most lineages, some regions showed repeated introgression and others almost none. Regions with high introgression tended to be near the donors’ origin of transfer sites. To determine whether introgressed alleles imposed a genetic load, we extended the experiment for 200 generations without recombination and sequenced whole-population samples. Beneficial alleles in the recipient populations were occasionally driven extinct by maladaptive donor-derived alleles. On balance, our analyses indicate that the plasmid-mediated recombination was sufficiently frequent to drive donor alleles to fixation without providing much, if any, selective advantage. PMID:29385126

Construct validity of the Work Productivity and Activity Impairment questionnaire across informal caregivers of chronically ill older patients.

PubMed

Giovannetti, Erin R; Wolff, Jennifer L; Frick, Kevin D; Boult, Chad

2009-09-01

To assess the validity of the Work Productivity and Activity Impairment questionnaire as adapted for caregiving (WPAI:CG) to measure productivity loss (hours missed from work, impairment while at work, and impairment in regular activities) due to unpaid caregiving for medically complex older adults. The WPAI:CG was administered along with the Caregiver Strain Index (CSI) and Center for Epidemiologic Studies Depression Scale (CESD) to a caregiving population (N = 308) enrolled with their older, medically complex care-recipient in a cluster-randomized controlled study. Correlation coefficients were calculated between each productivity variable derived from the WPAI:CG and CSI/CESD scores. Nonparametric tests for trend across ordered groups were carried out to examine the relationship between each productivity variable and the intensity of the caregiving. Significant positive correlations were found between work productivity loss and caregiving-related strain (r = 0.45) and depression (r = 0.30). Measures of productivity loss were also highly associated with caregiving intensity (P < 0.05) and care-recipient medical care use (P < 0.05). The average employed caregiver reported 1.5 hours absence from work in the previous week and 18.5% reduced productivity while at work due to caregiving. Employed and nonemployed caregivers reported 27.2% reduced productivity in regular activities in the previous week. The results indicate high convergent validity of the WPAI:CG questionnaire. This measure could facilitate research on the cost-effectiveness of caregiver-workplace interventions and provide employers and policy experts with a more accurate and comprehensive estimate of caregiving-related costs incurred by employers and society.

Breast cancer screening among shift workers: a nationwide population-based survey in Korea.

PubMed

Son, Heesook; Kang, Youngmi

2017-04-01

We aimed to examine the association between shift work types and participation in breast cancer screening (BCS) programs by comparing rates of participation for BCS among regular daytime workers and alternative shift workers using data from a nationally representative, population-based survey conducted in Korea. In addition, the results were analyzed according to sociodemographic factors, including occupation, education, income, private health insurance, age, and number of working hours a week. This secondary cross-sectional analysis used data from the 2012 Korean National Health and Nutritional Examination Survey. The target population included women aged ≥ 40 years who responded as to whether they had undergone BCS in the previous year. Accordingly, we analyzed survey data for a total of 1,193 women and used a multivariate logistic regression analysis to evaluate the differences in factors affecting BCS between regular daytime and alternative shift workers. A logistic regression analysis was performed considering private health insurance as a significant sociodemographic factor for BCS among regular daytime shift workers. In contrast, none of the tested variables could significantly predict adherence to BCS among alternative shift workers. The results of this study suggest the need for the development of comprehensive workplace breast cancer prevention programs by considering shift work types. More attention should be given to female workers with low education levels, those who are uninsured, and young workers to improve the participation rate for BCS at the workplace.

The nearly neutral and selection theories of molecular evolution under the fisher geometrical framework: substitution rate, population size, and complexity.

PubMed

Razeto-Barry, Pablo; Díaz, Javier; Vásquez, Rodrigo A

2012-06-01

The general theories of molecular evolution depend on relatively arbitrary assumptions about the relative distribution and rate of advantageous, deleterious, neutral, and nearly neutral mutations. The Fisher geometrical model (FGM) has been used to make distributions of mutations biologically interpretable. We explored an FGM-based molecular model to represent molecular evolutionary processes typically studied by nearly neutral and selection models, but in which distributions and relative rates of mutations with different selection coefficients are a consequence of biologically interpretable parameters, such as the average size of the phenotypic effect of mutations and the number of traits (complexity) of organisms. A variant of the FGM-based model that we called the static regime (SR) represents evolution as a nearly neutral process in which substitution rates are determined by a dynamic substitution process in which the population's phenotype remains around a suboptimum equilibrium fitness produced by a balance between slightly deleterious and slightly advantageous compensatory substitutions. As in previous nearly neutral models, the SR predicts a negative relationship between molecular evolutionary rate and population size; however, SR does not have the unrealistic properties of previous nearly neutral models such as the narrow window of selection strengths in which they work. In addition, the SR suggests that compensatory mutations cannot explain the high rate of fixations driven by positive selection currently found in DNA sequences, contrary to what has been previously suggested. We also developed a generalization of SR in which the optimum phenotype can change stochastically due to environmental or physiological shifts, which we called the variable regime (VR). VR models evolution as an interplay between adaptive processes and nearly neutral steady-state processes. When strong environmental fluctuations are incorporated, the process becomes a selection model in which evolutionary rate does not depend on population size, but is critically dependent on the complexity of organisms and mutation size. For SR as well as VR we found that key parameters of molecular evolution are linked by biological factors, and we showed that they cannot be fixed independently by arbitrary criteria, as has usually been assumed in previous molecular evolutionary models.

The well-being of community-dwelling near-centenarians and centenarians in Hong Kong a qualitative study

PubMed Central

2014-01-01

Background Hong Kong has one of the highest life expectancy rankings in the world. The number of centenarians and near-centenarians has been increasing locally and internationally. The relative growth of this population is a topic of immense importance for population and health policy makers. Living long and living well are two overlapping but distinct research topics. We previously conducted a quantitative study on 153 near-centenarians and centenarians to explore a wide range of biopsychosocial correlates of health and “living long”. This paper reports a follow-up qualitative study examining the potential correlates of “living well” among near-centenarians and centenarians in Hong Kong. Methods Six cognitively, physically, and psychologically sound community-dwelling elders were purposively recruited from a previous quantitative study. Semi-structured interviews were conducted. Results Four major themes related to living long and well emerged from the responses of the participants: (a) Positive relations with others, (b) Positive events and happiness, (c) Hope for the future, and (d) Positive life attitude. Specifically, we found that having good interpersonal relationships, possessing a collection of positive life events, and maintaining salutary attitudes towards life are considered as important to psychological well-being by long-lived adults in Hong Kong. Most participants perceived their working life as most important to their life history and retired at very old ages. Conclusions These findings also shed light on the relationships between health, work, and old age. PMID:24886462

Working conditions in call-centers, the impact on employee health: a transversal study. Part II.

PubMed

Charbotel, Barbara; Croidieu, Sophie; Vohito, Michel; Guerin, Anne-Céline; Renaud, Liliane; Jaussaud, Joelle; Bourboul, Christian; Imbard, Isabelle; Ardiet, Dominique; Bergeret, Alain

2009-05-01

The present study sought to assess the impact of telephone call center employees' working conditions on health by identifying at-risk employment situations. A transversal study was performed in companies followed by 47 occupational physicians taking part (working conditions have been previously described). A self-administered medical questionnaire was used to collect data on absence due to sick leave, hearing and visual problems, musculoskeletal disorders, psychotropic drug use, etc. An analog-scale self-assessment of health status and a general health questionnaire (GHQ-12) were used. Personal or familial events that might underlie health problems and affect GHQ-12 results were quantified and taken into account in a logistic regression. A total of 2,130 call-handlers were included. Workers who had availed sick leave during the previous 12 months were 60%. The most frequent musculoskeletal complaints over the previous 12-month period concerned the cervical region (59%). During the same period, 77.3% of subjects experienced visual fatigue, 50% reported auditory fatigue signs and 47% vocal disturbance or fatigue. According to the Likert scale, 39.4% of workers had showed psychological distress. Almost 24% of the workers had used psychoactive medication during the previous 12 months. A significant association was found between psychological distress and the frequency of musculoskeletal disorders. Psychological distress and musculoskeletal disorders were significantly greater in workers with Job Strain and Iso Strain. After taking non-occupational factors into account, some occupational factors were found to increase the risk of psychological distress (Likert >12): imposed full-time schedule, being unable to simultaneously meet both quality and quantity requirements, situations of tension with clients, negative comments from superiors, and lack of recognition from superiors. This survey of over 2,000 call center employees highlighted the high frequency of psychological distress in this population and the health impact of working conditions.

Development and validation of a web-based questionnaire for surveying the health and working conditions of high-performance marine craft populations.

PubMed

de Alwis, Manudul Pahansen; Lo Martire, Riccardo; Äng, Björn O; Garme, Karl

2016-06-20

High-performance marine craft crews are susceptible to various adverse health conditions caused by multiple interactive factors. However, there are limited epidemiological data available for assessment of working conditions at sea. Although questionnaire surveys are widely used for identifying exposures, outcomes and associated risks with high accuracy levels, until now, no validated epidemiological tool exists for surveying occupational health and performance in these populations. To develop and validate a web-based questionnaire for epidemiological assessment of occupational and individual risk exposure pertinent to the musculoskeletal health conditions and performance in high-performance marine craft populations. A questionnaire for investigating the association between work-related exposure, performance and health was initially developed by a consensus panel under four subdomains, viz. demography, lifestyle, work exposure and health and systematically validated by expert raters for content relevance and simplicity in three consecutive stages, each iteratively followed by a consensus panel revision. The item content validity index (I-CVI) was determined as the proportion of experts giving a rating of 3 or 4. The scale content validity index (S-CVI/Ave) was computed by averaging the I-CVIs for the assessment of the questionnaire as a tool. Finally, the questionnaire was pilot tested. The S-CVI/Ave increased from 0.89 to 0.96 for relevance and from 0.76 to 0.94 for simplicity, resulting in 36 items in the final questionnaire. The pilot test confirmed the feasibility of the questionnaire. The present study shows that the web-based questionnaire fulfils previously published validity acceptance criteria and is therefore considered valid and feasible for the empirical surveying of epidemiological aspects among high-performance marine craft crews and similar populations. 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/

Novel synthetic Medea selfish genetic elements drive population replacement in Drosophila; a theoretical exploration of Medea-dependent population suppression.

PubMed

Akbari, Omar S; Chen, Chun-Hong; Marshall, John M; Huang, Haixia; Antoshechkin, Igor; Hay, Bruce A

2014-12-19

Insects act as vectors for diseases of plants, animals, and humans. Replacement of wild insect populations with genetically modified individuals unable to transmit disease provides a potentially self-perpetuating method of disease prevention. Population replacement requires a gene drive mechanism in order to spread linked genes mediating disease refractoriness through wild populations. We previously reported the creation of synthetic Medea selfish genetic elements able to drive population replacement in Drosophila. These elements use microRNA-mediated silencing of myd88, a maternally expressed gene required for embryonic dorso-ventral pattern formation, coupled with early zygotic expression of a rescuing transgene, to bring about gene drive. Medea elements that work through additional mechanisms are needed in order to be able to carry out cycles of population replacement and/or remove existing transgenes from the population, using second-generation elements that spread while driving first-generation elements out of the population. Here we report the synthesis and population genetic behavior of two new synthetic Medea elements that drive population replacement through manipulation of signaling pathways involved in cellular blastoderm formation or Notch signaling, demonstrating that in Drosophila Medea elements can be generated through manipulation of diverse signaling pathways. We also describe the mRNA and small RNA changes in ovaries and early embryos associated from Medea-bearing females. Finally, we use modeling to illustrate how Medea elements carrying genes that result in diapause-dependent female lethality could be used to bring about population suppression.

Fixation probabilities of evolutionary coordination games on two coupled populations

NASA Astrophysics Data System (ADS)

Zhang, Liye; Ying, Limin; Zhou, Jie; Guan, Shuguang; Zou, Yong

2016-09-01

Evolutionary forces resulted from competitions between different populations are common, which change the evolutionary behavior of a single population. In an isolated population of coordination games of two strategies (e.g., s1 and s2), the previous studies focused on determining the fixation probability that the system is occupied by only one strategy (s1) and their expectation times, given an initial mixture of two strategies. In this work, we propose a model of two interdependent populations, disclosing the effects of the interaction strength on fixation probabilities. In the well-mixing limit, a detailed linear stability analysis is performed, which allows us to find and to classify the different equilibria, yielding a clear picture of the bifurcation patterns in phase space. We demonstrate that the interactions between populations crucially alter the dynamic behavior. More specifically, if the coupling strength is larger than some threshold value, the critical initial density of one strategy (s1) that corresponds to fixation is significantly delayed. Instead, the two populations evolve to the opposite state of all (s2) strategy, which are in favor of the red queen hypothesis. We delineate the extinction time of strategy (s1) explicitly, which is an exponential form. These results are validated by systematic numerical simulations.

Predicting recovery criteria for threatened and endangered plant species on the basis of past abundances and biological traits.

PubMed

Neel, Maile C; Che-Castaldo, Judy P

2013-04-01

Recovery plans for species listed under the U.S. Endangered Species Act are required to specify measurable criteria that can be used to determine when the species can be delisted. For the 642 listed endangered and threatened plant species that have recovery plans, we applied recursive partitioning methods to test whether the number of individuals or populations required for delisting can be predicted on the basis of distributional and biological traits, previous abundance at multiple time steps, or a combination of traits and previous abundances. We also tested listing status (threatened or endangered) and the year the recovery plan was written as predictors of recovery criteria. We analyzed separately recovery criteria that were stated as number of populations and as number of individuals (population-based and individual-based criteria, respectively). Previous abundances alone were relatively good predictors of population-based recovery criteria. Fewer populations, but a greater proportion of historically known populations, were required to delist species that had few populations at listing compared with species that had more populations at listing. Previous abundances were also good predictors of individual-based delisting criteria when models included both abundances and traits. The physiographic division in which the species occur was also a good predictor of individual-based criteria. Our results suggest managers are relying on previous abundances and patterns of decline as guidelines for setting recovery criteria. This may be justifiable in that previous abundances inform managers of the effects of both intrinsic traits and extrinsic threats that interact and determine extinction risk. © 2013 Society for Conservation Biology.

Postmating-prezygotic isolation is not an important source of selection for reinforcement within and between species in Drosophila pseudoobscura and D. persimilis.

PubMed

Lorch, Patrick D; Servedio, Maria R

2005-05-01

Most work on adaptive speciation to date has focused on the role of low hybrid fitness as the force driving reinforcement (the evolution of premating isolation after secondary contact that reduces the likelihood of matings between populations). However, recent theoretical work has shown that postmating, prezygotic incompatibilities may also be important in driving premating isolation. We quantified premating, postmating-prezygotic, and early postzygotic fitness effects in crosses among three populations: Drosophila persimilis, D. pseudoobscura USA (sympatric to D. persimilis), and D. pseudoobscura Bogotá (allopatric to D. persimilis). Interspecific matings were more likely to fail when they involved the sympatric populations than when they involved the allopatric populations, consistent with reinforcement. We also found that failure rate in sympatric mating trials depended on whether D. persimilis females were paired with D. pseudoobscura males or the reverse. This asymmetry most likely indicates differences in discrimination against heterospecific males by females. By measuring egg laying rate, fertilization success and hatching success, we also compared components of postmating-prezygotic and early postzygotic isolation. Postmating-prezygotic fitness costs were small and not distinguishable between hetero- and conspecific crosses. Early postzygotic fitness effects due to hatching success differences were also small in between-population crosses. There was, however, a postzygotic fitness effect that may have resulted from an X-linked allele found in one of the two strains of D. pseudoobscura USA. We conclude that the postmating-prezygotic fitness costs we measured probably did not drive premating isolation in these species. Premating isolation is most likely driven in sympatric populations by previously known hybrid male sterility.

Frailty, prefrailty and employment outcomes in Health and Employment After Fifty (HEAF) Study.

PubMed

Palmer, Keith T; D'Angelo, Stefania; Harris, E Clare; Linaker, Cathy; Gale, Catharine R; Evandrou, Maria; Syddall, Holly; van Staa, Tjeerd; Cooper, Cyrus; Aihie Sayer, Avan; Coggon, David; Walker-Bone, Karen

2017-07-01

Demographic changes are requiring people to work longer. No previous studies, however, have focused on whether the 'frailty' phenotype (which predicts adverse events in the elderly) is associated with employment difficulties. To provide information, we assessed associations in the Health and Employment After Fifty Study, a population-based cohort of 50-65-year olds. Subjects, who were recruited from 24 English general practices, completed a baseline questionnaire on 'prefrailty' and 'frailty' (adapted Fried criteria) and several work outcomes, including health-related job loss (HRJL), prolonged sickness absence (>20 days vs less, past 12 months), having to cut down substantially at work and difficulty coping with work's demands. Associations were assessed using logistic regression and population attributable fractions (PAFs) were calculated. In all, 3.9% of 8095 respondents were classed as 'frail' and 31.6% as 'prefrail'. Three-quarters of the former were not in work, while 60% had left their last job on health grounds (OR for HRJL vs non-frail subjects, 30.0 (95% CI 23.0 to 39.2)). Among those in work, ORs for prolonged sickness absence, cutting down substantially at work and struggling with work's physical demands ranged from 10.7 to 17.2. The PAF for HRJL when any frailty marker was present was 51.8% and that for prolonged sickness absence was 32.5%. Associations were strongest with slow reported walking speed. Several associations were stronger in manual workers than in managers. Fried frailty symptoms are not uncommon in mid-life and are strongly linked with economically important adverse employment outcomes. Frailty could represent an important target for prevention. 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/.

Making innovations accessible to the poor through implementation research.

PubMed

Squire, S B; Ramsay, A R C; van den Hof, S; Millington, K A; Langley, I; Bello, G; Kritski, A; Detjen, A; Thomson, R; Cobelens, F; Mann, G H

2011-07-01

Within countries, poorer populations have greater health needs and less access to good medical care than better-off populations. This is particularly true for tuberculosis (TB), the archetypal disease of poverty. Innovations also tend to become available to better-off populations well before they become available to those who need them the most. In a new era of innovations for TB diagnosis and treatment, it is increasingly important not only to be sure that these innovations can work in terms of accuracy and efficacy, but also that they will work, especially for the poor. We argue that after an innovation or a group of innovations has been endorsed, based on demonstrated accuracy and/or efficacy, introduction into routine practice should proceed through implementation by research. Cluster-randomised pragmatic trials are suited to this approach, and permit the prospective collection of evidence needed for full impact assessment according to a previously published framework. The novel approach of linking transmission modelling with operational modelling provides a methodology for expanding and enhancing the range of evidence, and can be used alongside evidence from pragmatic implementation trials. This evidence from routine practice should then be used to ensure that innovations in TB control are used for positive action for all, and particularly the poor.

A Framework to Address Challenges in Communicating the Developmental Origins of Health and Disease

PubMed Central

Winett, Liana; Wallack, Lawrence; Richardson, Dawn; Boone-Heinonen, Janne; Messer, Lynne

2017-01-01

Findings from the field of Developmental Origins of Health and Disease (DOHaD) suggest that some of the most pressing public health problems facing communities today may begin much earlier than previously understood. In particular, this body of work provides evidence that social, physical, chemical, environmental, and behavioral influences in early life play a significant role in establishing vulnerabilities for chronic disease later in life. Further, because this work points to the importance of adverse environmental exposures that cluster in population groups, it suggests that existing opportunities to intervene at a population level may need to refocus their efforts “upstream” to sufficiently combat the fundamental causes of disease. To translate these findings into improved public health, however, the distance between scientific discovery and population application will need to be bridged by conversations across a breadth of disciplines and social roles. And importantly, those involved will likely begin without a shared vocabulary or conceptual starting point. The purpose of this paper is to support and inform the translation of DOHaD findings from the bench to population-level health promotion and disease prevention, by: 1) Discussing the unique communication challenges inherent to translation of DOHaD for broad audiences, 2) Introducing the First-hit/Second-hit Framework with an epidemiologic planning matrix as a model for conceptualizing and structuring communication around DOHaD, and 3) Discussing the ways in which patterns of communicating DOHaD findings can expand the range of solutions considered, and encourage discussion of population-level solutions in relation to one another, rather than in isolation. PMID:27449924

A Framework to Address Challenges in Communicating the Developmental Origins of Health and Disease.

PubMed

Winett, Liana; Wallack, Lawrence; Richardson, Dawn; Boone-Heinonen, Janne; Messer, Lynne

2016-09-01

Findings from the field of Developmental Origins of Health and Disease (DOHaD) suggest that some of the most pressing public health problems facing communities today may begin much earlier than previously understood. In particular, this body of work provides evidence that social, physical, chemical, environmental, and behavioral influences in early life play a significant role in establishing vulnerabilities for chronic disease later in life. Further, because this work points to the importance of adverse environmental exposures that cluster in population groups, it suggests that existing opportunities to intervene at a population level may need to refocus their efforts "upstream" to sufficiently combat the fundamental causes of disease. To translate these findings into improved public health, however, the distance between scientific discovery and population application will need to be bridged by conversations across a breadth of disciplines and social roles. And importantly, those involved will likely begin without a shared vocabulary or conceptual starting point. The purpose of this paper is to support and inform the translation of DOHaD findings from the bench to population-level health promotion and disease prevention, by: (1) discussing the unique communication challenges inherent to translation of DOHaD for broad audiences, (2) introducing the First-hit/Second-hit Framework with an epidemiologic planning matrix as a model for conceptualizing and structuring communication around DOHaD, and (3) discussing the ways in which patterns of communicating DOHaD findings can expand the range of solutions considered and encourage discussion of population-level solutions in relation to one another, rather than in isolation.

TESTING STELLAR POPULATION SYNTHESIS MODELS WITH SLOAN DIGITAL SKY SURVEY COLORS OF M31's GLOBULAR CLUSTERS

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

Peacock, Mark B.; Zepf, Stephen E.; Maccarone, Thomas J.

2011-08-10

Accurate stellar population synthesis models are vital in understanding the properties and formation histories of galaxies. In order to calibrate and test the reliability of these models, they are often compared with observations of star clusters. However, relatively little work has compared these models in the ugriz filters, despite the recent widespread use of this filter set. In this paper, we compare the integrated colors of globular clusters in the Sloan Digital Sky Survey (SDSS) with those predicted from commonly used simple stellar population (SSP) models. The colors are based on SDSS observations of M31's clusters and provide the largestmore » population of star clusters with accurate photometry available from the survey. As such, it is a unique sample with which to compare SSP models with SDSS observations. From this work, we identify a significant offset between the SSP models and the clusters' g - r colors, with the models predicting colors which are too red by g - r {approx} 0.1. This finding is consistent with previous observations of luminous red galaxies in the SDSS, which show a similar discrepancy. The identification of this offset in globular clusters suggests that it is very unlikely to be due to a minority population of young stars. The recently updated SSP model of Maraston and Stroembaeck better represents the observed g - r colors. This model is based on the empirical MILES stellar library, rather than theoretical libraries, suggesting an explanation for the g - r discrepancy.« less

Incremental Learning With Selective Memory (ILSM): Towards Fast Prostate Localization for Image Guided Radiotherapy

PubMed Central

Gao, Yaozong; Zhan, Yiqiang

2015-01-01

Image-guided radiotherapy (IGRT) requires fast and accurate localization of the prostate in 3-D treatment-guided radiotherapy, which is challenging due to low tissue contrast and large anatomical variation across patients. On the other hand, the IGRT workflow involves collecting a series of computed tomography (CT) images from the same patient under treatment. These images contain valuable patient-specific information yet are often neglected by previous works. In this paper, we propose a novel learning framework, namely incremental learning with selective memory (ILSM), to effectively learn the patient-specific appearance characteristics from these patient-specific images. Specifically, starting with a population-based discriminative appearance model, ILSM aims to “personalize” the model to fit patient-specific appearance characteristics. The model is personalized with two steps: backward pruning that discards obsolete population-based knowledge and forward learning that incorporates patient-specific characteristics. By effectively combining the patient-specific characteristics with the general population statistics, the incrementally learned appearance model can localize the prostate of a specific patient much more accurately. This work has three contributions: 1) the proposed incremental learning framework can capture patient-specific characteristics more effectively, compared to traditional learning schemes, such as pure patient-specific learning, population-based learning, and mixture learning with patient-specific and population data; 2) this learning framework does not have any parametric model assumption, hence, allowing the adoption of any discriminative classifier; and 3) using ILSM, we can localize the prostate in treatment CTs accurately (DSC ∼0.89) and fast (∼4 s), which satisfies the real-world clinical requirements of IGRT. PMID:24495983

Identification of four novel variants that influence central corneal thickness in multi-ethnic Asian populations.

PubMed

Cornes, Belinda K; Khor, Chiea Chuen; Nongpiur, Monisha E; Xu, Liang; Tay, Wan-Ting; Zheng, Yingfeng; Lavanya, Raghavan; Li, Yang; Wu, Renyi; Sim, Xueling; Wang, Ya-Xing; Chen, Peng; Teo, Yik Ying; Chia, Kee-Seng; Seielstad, Mark; Liu, Jianjun; Hibberd, Martin L; Cheng, Ching-Yu; Saw, Seang-Mei; Tai, E-Shyong; Jonas, Jost B; Vithana, Eranga N; Wong, Tien Y; Aung, Tin

2012-01-15

Central corneal thickness (CCT) is a highly heritable trait. Genes that significantly influence CCT can be candidate genes for common disorders in which CCT has been implicated, such as primary open-angle glaucoma (POAG) and keratoconus. Because the genetic factors controlling CCT in different Asian populations are unclear, we have built on previous work conducted on Singaporean Indians and Malays and extended our hypothesis to individuals of Chinese descent. We have followed up on all suggestive signals of association with CCT (P < 10(-4)) from the previously reported meta-analysis comprising Indians and Malays in a sample of Chinese individuals (n= 2681). In the combined sample (n= 7711), strong evidence of association was observed at four novel loci: IBTK on chromosome 6q14.1; CHSY1 on chromosome 15q26.3; and intergenic regions on chromosomes 7q11.2 and 9p23 (8.01 × 10(-11) < λ(GC) corrected P(meta) < 8.72 × 10(-8)). These four new loci explain an additional 4.3% of the total CCT variance across the sample cohorts over and above that of previously identified loci. We also extend on a previous finding at a fifth locus (AKAP13) where a new single-nucleotide polymorphism (rs1821481, P(meta) = 9.99 × 10(-9)) was found to be significantly more informative compared with the previously reported rs6496932 (P(meta) = 3.64 × 10(-5)). Performing association analysis in Asians may lead to the discovery of ethnic-specific genes that control CCT, offering further mechanistic insights into the regulation of CCT. In addition, it may also provide several candidate genes for interrogation for POAG, keratoconus and possible racial/ethnic variations. © The Author 2011. Published by Oxford University Press. All rights reserved.

Alternative Constraint Handling Technique for Four-Bar Linkage Path Generation

NASA Astrophysics Data System (ADS)

Sleesongsom, S.; Bureerat, S.

2018-03-01

This paper proposes an extension of a new concept for path generation from our previous work by adding a new constraint handling technique. The propose technique was initially designed for problems without prescribed timing by avoiding the timing constraint, while remain constraints are solving with a new constraint handling technique. The technique is one kind of penalty technique. The comparative study is optimisation of path generation problems are solved using self-adaptive population size teaching-learning based optimization (SAP-TLBO) and original TLBO. In this study, two traditional path generation test problem are used to test the proposed technique. The results show that the new technique can be applied with the path generation problem without prescribed timing and gives better results than the previous technique. Furthermore, SAP-TLBO outperforms the original one.

The ASAS-SN Bright Supernova Catalog – II. 2015

DOE PAGES

Holoien, T. W. -S.; Brown, J. S.; Stanek, K. Z.; ...

2017-01-16

Here, this paper presents information for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) during 2015, its second full year of operations. The same information is presented for bright (mV ≤ 17), spectroscopically confirmed supernovae discovered by other sources in 2015. As with the first ASAS-SN bright supernova catalogue, we also present redshifts and near-ultraviolet through infrared magnitudes for all supernova host galaxies in both samples. Combined with our previous catalogue, this work comprises a complete catalogue of 455 supernovae from multiple professional and amateur sources, allowing for population studies that were previously impossible. This is themore » second of a series of yearly papers on bright supernovae and their hosts from the ASAS-SN team.« less

The ASAS-SN Bright Supernova Catalog – II. 2015

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

Holoien, T. W. -S.; Brown, J. S.; Stanek, K. Z.

Here, this paper presents information for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) during 2015, its second full year of operations. The same information is presented for bright (mV ≤ 17), spectroscopically confirmed supernovae discovered by other sources in 2015. As with the first ASAS-SN bright supernova catalogue, we also present redshifts and near-ultraviolet through infrared magnitudes for all supernova host galaxies in both samples. Combined with our previous catalogue, this work comprises a complete catalogue of 455 supernovae from multiple professional and amateur sources, allowing for population studies that were previously impossible. This is themore » second of a series of yearly papers on bright supernovae and their hosts from the ASAS-SN team.« less

A Population-based survey of the prevalence of HIV, syphilis, hepatitis B and hepatitis C infections and associated risk factors among young women in Vitória, Brazil

PubMed Central

Miranda, Angelica Espinosa; Figueiredo, Nínive Camilo; Schmidt, Renylena; Page-Shafer, Kimberly

2017-01-01

Objective To estimate the prevalence of HIV, hepatitis B (HBV) and C (HCV) and syphilis infections and associated risk exposures in a population-based sample of young women in Vitória, Brazil. Methods From March to December 2006, a cross-sectional sample of women aged 18 to 29 years was recruited into a single stage, population-based study. Serological markers of HIV, HBV, HCV, and syphilis infections and associated risk exposures were assessed. Results Of 1,200 eligible women, 1,029 (85.8%) enrolled. Median age was 23 (interquartile range [IQR] 20, 26) years; 32.2% had ≤ 8 years of education. The survey weighted prevalence estimates were: HIV, 0.6% (95% CI), 0.1%, 1.1%); anti-HBc, 4.2% (3.0%, 5.4%); HBsAg, 0.9% (0.4%, 1.6%); anti-HCV, 0.6% (0.1%, 1.1%) and syphilis 1.2% (0.5%, 1.9%). Overall, 6.1% had at least one positive serological marker for any of the tested infection. A majority (87.9%) was sexually active, of whom 12.1% reported a previously diagnosed sexually transmitted infection (STI) and 1.4% a history of commercial sex work. Variables independently associated with any positive serological test included: older age (≥25 vs. <25 years), low monthly income (≤ 4× vs. >4× minimum wage), previously diagnosed STI, ≥ 1 sexual partner, and any illicit drug use. Conclusions These are the first population-based estimates of the prevalence of exposure to these infectious diseases and related risks in young women, a population for whom there is a scarcity of data in Brazil. PMID:18401700

Galaxy And Mass Assembly (GAMA): galaxy environments and star formation rate variations

NASA Astrophysics Data System (ADS)

Wijesinghe, D. B.; Hopkins, A. M.; Brough, S.; Taylor, E. N.; Norberg, P.; Bauer, A.; Brown, M. J. I.; Cameron, E.; Conselice, C. J.; Croom, S.; Driver, S.; Grootes, M. W.; Jones, D. H.; Kelvin, L.; Loveday, J.; Pimbblet, K. A.; Popescu, C. C.; Prescott, M.; Sharp, R.; Baldry, I.; Sadler, E. M.; Liske, J.; Robotham, A. S. G.; Bamford, S.; Bland-Hawthorn, J.; Gunawardhana, M.; Meyer, M.; Parkinson, H.; Drinkwater, M. J.; Peacock, J.; Tuffs, R.

2012-07-01

We present a detailed investigation into the effects of galaxy environment on their star formation rates (SFRs) using galaxies observed in the Galaxy And Mass Assembly (GAMA) survey. We use three independent volume-limited samples of galaxies within z < 0.2 and Mr < -17.8. We investigate the known SFR-density relationship and explore in detail the dependence of SFR on stellar mass and density. We show that the SFR-density trend is only visible when we include the passive galaxy population along with the star-forming population. This SFR-density relation is absent when we consider only the star-forming population of galaxies, consistent with previous work. While there is a strong dependence of the EWHα on density we find, as in previous studies, that these trends are largely due to the passive galaxy population and this relationship is absent when considering a 'star-forming' sample of galaxies. We find that stellar mass has the strongest influence on SFR and EWHα with the environment having no significant effect on the star formation properties of the star-forming population. We also show that the SFR-density relationship is absent for both early- and late-type star-forming galaxies. We conclude that the stellar mass has the largest impact on the current SFR of a galaxy, and any environmental effect is not detectable. The observation that the trends with density are due to the changing morphology fraction with density implies that the time-scales must be very short for any quenching of the SFR in infalling galaxies. Alternatively, galaxies may in fact undergo predominantly in situ evolution where the infall and quenching of galaxies from the field into dense environments is not the dominant evolutionary mode.

U-Pb detrital zircon dates and provenance data from the Beaufort Group (Karoo Supergroup) reflect sedimentary recycling and air-fall tuff deposition in the Permo-Triassic Karoo foreland basin

NASA Astrophysics Data System (ADS)

Viglietti, Pia A.; Frei, Dirk; Rubidge, Bruce S.; Smith, Roger M. H.

2018-07-01

Detrital zircon U-Pb age dating was used for provenance determination and maximum age of deposition for the Upper Permian (upper Teekloof and Balfour formations) and Lower Triassic (Katberg Formation) lithostratigraphic subdivisions of the Beaufort Group of South Africa's Karoo Basin. Ten samples were analysed using laser ablation - single collector - magnetic sectorfield - inductively coupled plasma - mass spectrometry (LA-SF-ICP-MS). The results reveal a dominant Late Carboniferous-Late Permian population (250 ± 5 Ma - 339 ± 5 Ma), a secondary Cambrian-Neoproterozoic (489 ± 5 Ma to 878 ± 24 Ma) population, a minor Mesoproterozoic (908 ± 24 Ma to 1308 ± 23) population, and minor occurrences of Devonian, Ordovician, Proterozoic and Archean zircon grains. Multiple lines of evidence (e.g. roundness and fragmentary nature of zircons, palaeo-current directions, and previous work), suggest the older zircon populations are related to sedimentary recycling in the Gondwanide Orogeny. The youngest and dominant population contain elongate euhedral grains interpreted to be directly derived from their protolith. Since zircons form in felsic igneous rocks, and no igneous rocks of Late Permian age occur in the Karoo Basin, these findings suggest significant input of volcanic material by ash falls. These results support sedimentological and palaeontological data for a Lopingian (Late Permian) age for the upper Beaufort Group, but contradict previous workers who retrieved Early Triassic dates from zircons in ashes for the Beaufort and Ecca Groups. Pb-loss not revealed by resolvable discordance on the concordia diagram, and metamictization of natural zircons are not factored into the conclusions of earlier workers.

Tautomerism in cytosine and uracil: an experimental and theoretical core level spectroscopic study.

PubMed

Feyer, Vitaliy; Plekan, Oksana; Richter, Robert; Coreno, Marcello; Vall-llosera, Gemma; Prince, Kevin C; Trofimov, Alexander B; Zaytseva, Irina L; Moskovskaya, Tatyana E; Gromov, Evgeniy V; Schirmer, Jochen

2009-05-14

The O, N, and C 1s core level photoemission spectra of the nucleobases cytosine and uracil have been measured in the vapor phase, and the results have been interpreted via theoretical calculations. Our calculations accurately predict the relative binding energies of the core level features observed in the experimental photoemission results and provide a full assignment. In agreement with previous work, a single tautomer of uracil is populated at 405 K, giving rise to relatively simple spectra. At 450 K, three tautomers of cytosine, one of which may consist of two rotamers, are identified, and their populations are determined. This resolves inconsistencies between recent laser studies of this molecule in which the rare imino-oxo tautomer was not observed and older microwave spectra in which it was reported.

Increasing neonicotinoid use and the declining butterfly fauna of lowland California.

PubMed

Forister, Matthew L; Cousens, Bruce; Harrison, Joshua G; Anderson, Kayce; Thorne, James H; Waetjen, Dave; Nice, Chris C; De Parsia, Matthew; Hladik, Michelle L; Meese, Robert; van Vliet, Heidi; Shapiro, Arthur M

2016-08-01

The butterfly fauna of lowland Northern California has exhibited a marked decline in recent years that previous studies have attributed in part to altered climatic conditions and changes in land use. Here, we ask if a shift in insecticide use towards neonicotinoids is associated with butterfly declines at four sites in the region that have been monitored for four decades. A negative association between butterfly populations and increasing neonicotinoid application is detectable while controlling for land use and other factors, and appears to be more severe for smaller-bodied species. These results suggest that neonicotinoids could influence non-target insect populations occurring in proximity to application locations, and highlights the need for mechanistic work to complement long-term observational data. © 2016 The Author(s).

The prevalence of headache in a population of health care workers and the effects on productivity costs.

PubMed

Cristofolini, A; Dalla Serra, P; Scherillo, G; Orrico, D; Micciolo, R

2008-01-01

Headache is reported as one of the most frequent causes of lost work time and reduced work efficiency. The aim of this study was to determine the impact of headache and its consequences as regards absence from work among health care workers and reduced work efficiency. The prevalence of headache and its effects on ability in daily activities and work productivity were studied and assessed on occasion of the periodic health examination of 3,620 health care workers of the Provincial Health Care Trust, Trento, by means of the MIDAS disability scale and parameters derived from criteria established by the International Headache Society. In the previous three months 27.1% had suffered from at least one episode of headache. The prevalence of migraine was 9.9%, with a significantly higher percentage among women (12.9%). The total administrative costs estimated per working year were about Euro 136,836 for migraine and about Euro 44,614 for tension-type headache (TTH). The prevalence and features of migraine and TTH were studied. Data regarding the prevalence of migraine were similar to the results reported in other studies. The vast majority of the individuals reported no absenteeism over the previous three months. The study confirmed that we should continue to manage the presumed job-related trigger factors in the best possible manner, counselling should be made available to health care workers during the periodic health examinations or upon request, and if needed, the patient should be sent to a neurology specialist for a free examination and appropriate pharmacological treatment.

Work-related burnout, job satisfaction, intent to leave, and nurse-assessed quality of care among travel nurses.

PubMed

Faller, Marcia S; Gates, Michael G; Georges, Jane M; Connelly, Cynthia D

2011-02-01

This research study examines work-related burnout, job satisfaction, nurse-assessed quality of care, and intent to leave in travel nurses, a population that has not been studied previously. Travel nurses are frequently used to supplement nursing staff in acute care hospitals, especially in times of shortage--understanding their satisfaction with the job may further illuminate the problem of nurse job dissatisfaction in general. Ordinary least-squares regression analyses were used to examine the influence of nurse and workplace characteristics on work-related burnout, job satisfaction, intent to leave, and perceived quality of care. Quality of care and job satisfaction were significantly influenced by whether a hospital held Magnet designation. As the number of patients cared for increases, there was a significant increase in work-related burnout. Work-related burnout was also significantly lower for nurses working in California. The results of this study suggest that different workplace characteristics influence the perceptions of quality of care provided at a hospital facility and the degree to which a nurse is either burned out or satisfied with his/her job.

Genetic demographic networks: Mathematical model and applications.

PubMed

Kimmel, Marek; Wojdyła, Tomasz

2016-10-01

Recent improvement in the quality of genetic data obtained from extinct human populations and their ancestors encourages searching for answers to basic questions regarding human population history. The most common and successful are model-based approaches, in which genetic data are compared to the data obtained from the assumed demography model. Using such approach, it is possible to either validate or adjust assumed demography. Model fit to data can be obtained based on reverse-time coalescent simulations or forward-time simulations. In this paper we introduce a computational method based on mathematical equation that allows obtaining joint distributions of pairs of individuals under a specified demography model, each of them characterized by a genetic variant at a chosen locus. The two individuals are randomly sampled from either the same or two different populations. The model assumes three types of demographic events (split, merge and migration). Populations evolve according to the time-continuous Moran model with drift and Markov-process mutation. This latter process is described by the Lyapunov-type equation introduced by O'Brien and generalized in our previous works. Application of this equation constitutes an original contribution. In the result section of the paper we present sample applications of our model to both simulated and literature-based demographies. Among other we include a study of the Slavs-Balts-Finns genetic relationship, in which we model split and migrations between the Balts and Slavs. We also include another example that involves the migration rates between farmers and hunters-gatherers, based on modern and ancient DNA samples. This latter process was previously studied using coalescent simulations. Our results are in general agreement with the previous method, which provides validation of our approach. Although our model is not an alternative to simulation methods in the practical sense, it provides an algorithm to compute pairwise distributions of alleles, in the case of haploid non-recombining loci such as mitochondrial and Y-chromosome loci in humans. Copyright © 2016 Elsevier Inc. All rights reserved.

Causes and Correlates of Calf Mortality in Captive Asian Elephants (Elephas maximus)

PubMed Central

Mar, Khyne U.; Lahdenperä, Mirkka; Lummaa, Virpi

2012-01-01

Juvenile mortality is a key factor influencing population growth rate in density-independent, predation-free, well-managed captive populations. Currently at least a quarter of all Asian elephants live in captivity, but both the wild and captive populations are unsustainable with the present fertility and calf mortality rates. Despite the need for detailed data on calf mortality to manage effectively populations and to minimize the need for capture from the wild, very little is known of the causes and correlates of calf mortality in Asian elephants. Here we use the world's largest multigenerational demographic dataset on a semi-captive population of Asian elephants compiled from timber camps in Myanmar to investigate the survival of calves (n = 1020) to age five born to captive-born mothers (n = 391) between 1960 and 1999. Mortality risk varied significantly across different ages and was higher for males at any age. Maternal reproductive history was associated with large differences in both stillbirth and liveborn mortality risk: first-time mothers had a higher risk of calf loss as did mothers producing another calf soon (<3.7 years) after a previous birth, and when giving birth at older age. Stillbirth (4%) and pre-weaning mortality (25.6%) were considerably lower than those reported for zoo elephants and used in published population viability analyses. A large proportion of deaths were caused by accidents and lack of maternal milk/calf weakness which both might be partly preventable by supplementary feeding of mothers and calves and work reduction of high-risk mothers. Our results on Myanmar timber elephants with an extensive keeping system provide an important comparison to compromised survivorship reported in zoo elephants. They have implications for improving captive working elephant management systems in range countries and for refining population viability analyses with realistic parameter values in order to predict future population size of the Asian elephant. PMID:22396757

Causes and correlates of calf mortality in captive Asian elephants (Elephas maximus).

PubMed

Mar, Khyne U; Lahdenperä, Mirkka; Lummaa, Virpi

2012-01-01

Juvenile mortality is a key factor influencing population growth rate in density-independent, predation-free, well-managed captive populations. Currently at least a quarter of all Asian elephants live in captivity, but both the wild and captive populations are unsustainable with the present fertility and calf mortality rates. Despite the need for detailed data on calf mortality to manage effectively populations and to minimize the need for capture from the wild, very little is known of the causes and correlates of calf mortality in Asian elephants. Here we use the world's largest multigenerational demographic dataset on a semi-captive population of Asian elephants compiled from timber camps in Myanmar to investigate the survival of calves (n = 1020) to age five born to captive-born mothers (n = 391) between 1960 and 1999. Mortality risk varied significantly across different ages and was higher for males at any age. Maternal reproductive history was associated with large differences in both stillbirth and liveborn mortality risk: first-time mothers had a higher risk of calf loss as did mothers producing another calf soon (<3.7 years) after a previous birth, and when giving birth at older age. Stillbirth (4%) and pre-weaning mortality (25.6%) were considerably lower than those reported for zoo elephants and used in published population viability analyses. A large proportion of deaths were caused by accidents and lack of maternal milk/calf weakness which both might be partly preventable by supplementary feeding of mothers and calves and work reduction of high-risk mothers. Our results on Myanmar timber elephants with an extensive keeping system provide an important comparison to compromised survivorship reported in zoo elephants. They have implications for improving captive working elephant management systems in range countries and for refining population viability analyses with realistic parameter values in order to predict future population size of the Asian elephant.

Specificity and timescales of cortical adaptation as inferences about natural movie statistics.

PubMed

Snow, Michoel; Coen-Cagli, Ruben; Schwartz, Odelia

2016-10-01

Adaptation is a phenomenological umbrella term under which a variety of temporal contextual effects are grouped. Previous models have shown that some aspects of visual adaptation reflect optimal processing of dynamic visual inputs, suggesting that adaptation should be tuned to the properties of natural visual inputs. However, the link between natural dynamic inputs and adaptation is poorly understood. Here, we extend a previously developed Bayesian modeling framework for spatial contextual effects to the temporal domain. The model learns temporal statistical regularities of natural movies and links these statistics to adaptation in primary visual cortex via divisive normalization, a ubiquitous neural computation. In particular, the model divisively normalizes the present visual input by the past visual inputs only to the degree that these are inferred to be statistically dependent. We show that this flexible form of normalization reproduces classical findings on how brief adaptation affects neuronal selectivity. Furthermore, prior knowledge acquired by the Bayesian model from natural movies can be modified by prolonged exposure to novel visual stimuli. We show that this updating can explain classical results on contrast adaptation. We also simulate the recent finding that adaptation maintains population homeostasis, namely, a balanced level of activity across a population of neurons with different orientation preferences. Consistent with previous disparate observations, our work further clarifies the influence of stimulus-specific and neuronal-specific normalization signals in adaptation.

Specificity and timescales of cortical adaptation as inferences about natural movie statistics

PubMed Central

Snow, Michoel; Coen-Cagli, Ruben; Schwartz, Odelia

2016-01-01

Adaptation is a phenomenological umbrella term under which a variety of temporal contextual effects are grouped. Previous models have shown that some aspects of visual adaptation reflect optimal processing of dynamic visual inputs, suggesting that adaptation should be tuned to the properties of natural visual inputs. However, the link between natural dynamic inputs and adaptation is poorly understood. Here, we extend a previously developed Bayesian modeling framework for spatial contextual effects to the temporal domain. The model learns temporal statistical regularities of natural movies and links these statistics to adaptation in primary visual cortex via divisive normalization, a ubiquitous neural computation. In particular, the model divisively normalizes the present visual input by the past visual inputs only to the degree that these are inferred to be statistically dependent. We show that this flexible form of normalization reproduces classical findings on how brief adaptation affects neuronal selectivity. Furthermore, prior knowledge acquired by the Bayesian model from natural movies can be modified by prolonged exposure to novel visual stimuli. We show that this updating can explain classical results on contrast adaptation. We also simulate the recent finding that adaptation maintains population homeostasis, namely, a balanced level of activity across a population of neurons with different orientation preferences. Consistent with previous disparate observations, our work further clarifies the influence of stimulus-specific and neuronal-specific normalization signals in adaptation. PMID:27699416

Workplace gender composition and psychological distress: the importance of the psychosocial work environment.

PubMed

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.

Workplace gender composition and psychological distress: the importance of the psychosocial work environment

PubMed Central

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

Lower Lateral Cartilages: An Anatomic and Morphological Study in Noses of Black Southern Africans.

PubMed

McIntosh, Cameron N D; van Wyk, F Carl; Joubert, Gina; Seedat, Riaz Y

2017-03-01

The anatomy of the nose of different ethnic groups has been widely researched in order to facilitate a better understanding of the individual nose as a foundation for improving surgical outcomes. The only anatomical research of the lower lateral cartilages (LLCs) available to the surgeon working with an African patient is to extrapolate data from studies already published on African Americans. The aim of this descriptive cadaveric study was to assess the normal anatomy of the LLCs in noses of Black South Africans and compare this to data from studies on noses from Caucasian, Asian, Korean, and African-American populations. Ninety lower lateral cartilages of 45 cadavers of Black South Africans who did not have previous surgery or trauma to the nose were dissected. The morphological shapes and 12 standard anatomical measurements were recorded. The results were analyzed and compared to data in the literature from studies on lower lateral cartilages of Caucasian, Asian, Korean, and African-American populations. A statistically significant difference was found in terms of overall cartilage dimensions, distance from nasal rim, and morphological shapes, compared to all previously studied groups, including the African-American population. There were significant differences in cartilage dimensions between males and females. This translates to clinically significant data that is useful during reconstructive and aesthetic nasal surgery on patients with a Southern African background. This study sets norms for alar cartilages in Black Southern Africans.

Statistical aspects of evolution under natural selection, with implications for the advantage of sexual reproduction.

PubMed

Crouch, Daniel J M

2017-10-27

The prevalence of sexual reproduction remains mysterious, as it poses clear evolutionary drawbacks compared to reproducing asexually. Several possible explanations exist, with one of the most likely being that finite population size causes linkage disequilibria to randomly generate and impede the progress of natural selection, and that these are eroded by recombination via sexual reproduction. Previous investigations have either analysed this phenomenon in detail for small numbers of loci, or performed population simulations for many loci. Here we present a quantitative genetic model for fitness, based on the Price Equation, in order to examine the theoretical consequences of randomly generated linkage disequilibria when there are many loci. In addition, most previous work has been concerned with the long-term consequences of deleterious linkage disequilibria for population fitness. The expected change in mean fitness between consecutive generations, a measure of short-term evolutionary success, is shown under random environmental influences to be related to the autocovariance in mean fitness between the generations, capturing the effects of stochastic forces such as genetic drift. Interaction between genetic drift and natural selection, due to randomly generated linkage disequilibria, is demonstrated to be one possible source of mean fitness autocovariance. This suggests a possible role for sexual reproduction in reducing the negative effects of genetic drift, thereby improving the short-term efficacy of natural selection. Copyright © 2017 Elsevier Ltd. All rights reserved.

Do plants adjust their sex allocation and secondary sexual morphology in response to their neighbours?

PubMed Central

Vilas, Julia Sánchez; Pannell, John R.

2012-01-01

Background and aims Changes in the sex allocation (i.e. in pollen versus seed production) of hermaphroditic plants often occur in response to the environment. In some homosporous ferns, gametophytes choose their gender in response to chemical cues sent by neighbours, such that spores develop as male gametophytes if they perceive a female or hermaphrodite nearby. Here it is considered whether a similar process might occur in the androdioecious angiosperm species Mercurialis annua, in which males co-occur with hermaphrodites; previous work on a Spanish population of M. annua found that individuals were more likely to develop as males at high density. Methods Using a novel approach to treat plants with leachate from pots containing males or hermaphrodites of M. annua, the hypothesis that individuals assess their mating opportunities, and adjust their sex expression accordingly, was tested through an exchange of chemical cues through the soil. Key Results For the population under study, from Morocco, no evidence was found for soil-signal-dependent sex expression: neither sex ratios nor sex allocation differed among experimental treatments. Conclusions The results imply either that the Moroccan population under study behaves differently from that previously studied in Spain (pointing to potential geographical variation in plasticity for sex expression), or that our method failed to capture the signals used by M. annua for adjustment of sex expression. PMID:22899829

Dynamic feature analysis of vector-based images for neuropsychological testing

NASA Astrophysics Data System (ADS)

Smith, Stephen L.; Cervantes, Basilio R.

1998-07-01

The dynamic properties of human motor activities, such as those observed in the course of drawing simple geometric shapes, are considerably more complex and often more informative than the goal to be achieved; in this case a static line drawing. This paper demonstrates how these dynamic properties may be used to provide a means of assessing a patient's visuo-spatial ability -- an important component of neuropsychological testing. The work described here provides a quantitative assessment of visuo-spatial ability, whilst preserving the conventional test environment. Results will be presented for a clinical population of long-term haemodialysis patients and test population comprises three groups of children (1) 7-8 years, (2) 9-10 years and (3) 11-12 years, all of which have no known neurological dysfunction. Ten new dynamic measurements extracted from patient responses in conjunction with one static feature deduced from earlier work describe a patient's visuo-spatial ability in a quantitative manner with sensitivity not previously attainable. The dynamic feature measurements in isolation provide a unique means of tracking a patient's approach to motor activities and could prove useful in monitoring a child' visuo-motor development.

Steady-State ALPS for Real-Valued Problems

NASA Technical Reports Server (NTRS)

Hornby, Gregory S.

2009-01-01

The two objectives of this paper are to describe a steady-state version of the Age-Layered Population Structure (ALPS) Evolutionary Algorithm (EA) and to compare it against other GAs on real-valued problems. Motivation for this work comes from our previous success in demonstrating that a generational version of ALPS greatly improves search performance on a Genetic Programming problem. In making steady-state ALPS some modifications were made to the method for calculating age and the method for moving individuals up layers. To demonstrate that ALPS works well on real-valued problems we compare it against CMA-ES and Differential Evolution (DE) on five challenging, real-valued functions and on one real-world problem. While CMA-ES and DE outperform ALPS on the two unimodal test functions, ALPS is much better on the three multimodal test problems and on the real-world problem. Further examination shows that, unlike the other GAs, ALPS maintains a genotypically diverse population throughout the entire search process. These findings strongly suggest that the ALPS paradigm is better able to avoid premature convergence then the other GAs.

Suicide by occupation: systematic review and meta-analysis.

PubMed

Milner, Allison; Spittal, Matthew J; Pirkis, Jane; LaMontagne, Anthony D

2013-12-01

Previous research has shown that those employed in certain occupations, such as doctors and farmers, have an elevated risk of suicide, yet little research has sought to synthesise these findings across working-age populations. To summarise published research in this area through systematic review and meta-analysis. Random effects meta-analyses were used to calculate a pooled risk of suicide across occupational skill-level groups. Thirty-four studies were included in the meta-analysis. Elementary professions (e.g. labourers and cleaners) were at elevated risk compared with the working-age population (rate ratio (RR) = 1.84, 95% CI 1.46-2.33), followed by machine operators and deck crew (RR = 1.78, 95% CI 1.22-2.60) and agricultural workers (RR = 1.64, 95% CI 1.19-2.28). Results suggested a stepwise gradient in risk, with the lowest skilled occupations being at greater risk of suicide than the highest skill-level group. This is the first comprehensive meta-analytical review of suicide and occupation. There is a need for future studies to investigate explanations for the observed skill-level differences, particularly in people employed in lower skill-level groups.

Adaptation of human skin color in various populations.

PubMed

Deng, Lian; Xu, Shuhua

2018-01-01

Skin color is a well-recognized adaptive trait and has been studied extensively in humans. Understanding the genetic basis of adaptation of skin color in various populations has many implications in human evolution and medicine. Impressive progress has been made recently to identify genes associated with skin color variation in a wide range of geographical and temporal populations. In this review, we discuss what is currently known about the genetics of skin color variation. We enumerated several cases of skin color adaptation in global modern humans and archaic hominins, and illustrated why, when, and how skin color adaptation occurred in different populations. Finally, we provided a summary of the candidate loci associated with pigmentation, which could be a valuable reference for further evolutionary and medical studies. Previous studies generally indicated a complex genetic mechanism underlying the skin color variation, expanding our understanding of the role of population demographic history and natural selection in shaping genetic and phenotypic diversity in humans. Future work is needed to dissect the genetic architecture of skin color adaptation in numerous ethnic minority groups around the world, which remains relatively obscure compared with that of major continental groups, and to unravel the exact genetic basis of skin color adaptation.

[Approximation to the dynamics of meningococcal meningitis through dynamic systems and time series].

PubMed

Canals, M

1996-02-01

Meningococcal meningitis is subjected to epidemiological surveillance due to its severity and the occasional presentation of epidemic outbreaks. This work analyses previous disease models, generate new ones and analyses monthly cases using ARIMA time series models. The results show that disease dynamics for closed populations is epidemic and the epidemic size is related to the proportion of carriers and the transmissiveness of the agent. In open populations, disease dynamics depends on the admission rate of susceptible and the relative admission of infected individuals. Our model considers a logistic populational growth and carrier admission proportional to populational size, generating an endemic dynamics. Considering a non-instantaneous system response, a greater realism is obtained establishing that the endemic situation may present a dynamics highly sensitive to initial conditions, depending on the transmissiveness and proportion of susceptible individuals in the population. Time series model showed an adequate predictive capacity in terms no longer than 10 months. The lack of long term predictability was attributed to local changes in the proportion of carriers or on transmissiveness that lead to chaotic dynamics over a seasonal pattern. Predictions for 1995 and 1996 were obtained.

Characterization of a rare Unverricht-Lundborg disease mutation.

PubMed

Duarte, Ana Joana; Ribeiro, Diogo; Chaves, João; Amaral, Olga

2015-09-01

Cystatin B (CSTB) gene mutations cause Unverricht-Lundborg disease (ULD), a rare form of myoclonic epilepsy. The previous identification of a Portuguese patient, homozygous for a unique splicing defect (c.66G > A; p.Q22Q), provided awareness regarding the existence of variant forms of ULD. In this work we aimed at the characterization of this mutation at the population level and at the cellular level. The cellular fractionation studies here carried out showed mislocalization of the protein and add to the knowledge on this disease.

Distinguishing Error from Chaos in Ecological Time Series

NASA Astrophysics Data System (ADS)

Sugihara, George; Grenfell, Bryan; May, Robert M.

1990-11-01

Over the years, there has been much discussion about the relative importance of environmental and biological factors in regulating natural populations. Often it is thought that environmental factors are associated with stochastic fluctuations in population density, and biological ones with deterministic regulation. We revisit these ideas in the light of recent work on chaos and nonlinear systems. We show that completely deterministic regulatory factors can lead to apparently random fluctuations in population density, and we then develop a new method (that can be applied to limited data sets) to make practical distinctions between apparently noisy dynamics produced by low-dimensional chaos and population variation that in fact derives from random (high-dimensional)noise, such as environmental stochasticity or sampling error. To show its practical use, the method is first applied to models where the dynamics are known. We then apply the method to several sets of real data, including newly analysed data on the incidence of measles in the United Kingdom. Here the additional problems of secular trends and spatial effects are explored. In particular, we find that on a city-by-city scale measles exhibits low-dimensional chaos (as has previously been found for measles in New York City), whereas on a larger, country-wide scale the dynamics appear as a noisy two-year cycle. In addition to shedding light on the basic dynamics of some nonlinear biological systems, this work dramatizes how the scale on which data is collected and analysed can affect the conclusions drawn.

The differing magnitude distributions of the two Jupiter Trojan color populations

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

Wong, Ian; Brown, Michael E.; Emery, Joshua P., E-mail: iwong@caltech.edu

The Jupiter Trojans are a significant population of minor bodies in the middle solar system that have garnered substantial interest in recent years. Several spectroscopic studies of these objects have revealed notable bimodalities with respect to near-infrared spectra, infrared albedo, and color, which suggest the existence of two distinct groups among the Trojan population. In this paper, we analyze the magnitude distributions of these two groups, which we refer to as the red and less red color populations. By compiling spectral and photometric data from several previous works, we show that the observed bimodalities are self-consistent and categorize 221 ofmore » the 842 Trojans with absolute magnitudes in the range H<12.3 into the two color populations. We demonstrate that the magnitude distributions of the two color populations are distinct to a high confidence level (>95%) and fit them individually to a broken power law, with special attention given to evaluating and correcting for incompleteness in the Trojan catalog as well as incompleteness in our categorization of objects. A comparison of the best-fit curves shows that the faint-end power-law slopes are markedly different for the two color populations, which indicates that the red and less red Trojans likely formed in different locations. We propose a few hypotheses for the origin and evolution of the Trojan population based on the analyzed data.« less

The riddle of Tasmanian languages

PubMed Central

Bowern, Claire

2012-01-01

Recent work which combines methods from linguistics and evolutionary biology has been fruitful in discovering the history of major language families because of similarities in evolutionary processes. Such work opens up new possibilities for language research on previously unsolvable problems, especially in areas where information from other sources may be lacking. I use phylogenetic methods to investigate Tasmanian languages. Existing materials are so fragmentary that scholars have been unable to discover how many languages are represented in the sources. Using a clustering algorithm which identifies admixture, source materials representing more than one language are identified. Using the Neighbor-Net algorithm, 12 languages are identified in five clusters. Bayesian phylogenetic methods reveal that the families are not demonstrably related; an important result, given the importance of Tasmanian Aborigines for information about how societies have responded to population collapse in prehistory. This work provides insight into the societies of prehistoric Tasmania and illustrates a new utility of phylogenetics in reconstructing linguistic history. PMID:23015621

An R package for simulating growth and organic wastage in aquaculture farms in response to environmental conditions and husbandry practices

PubMed Central

Baldan, Damiano; Porporato, Erika Maria Diletta; Pastres, Roberto

2018-01-01

A new R software package, RAC, is presented. RAC allows to simulate the rearing cycle of 4 species, finfish and shellfish, highly important in terms of production in the Mediterranean Sea. The package works both at the scale of the individual and of the farmed population. Mathematical models included in RAC were all validated in previous works, and account for growth and metabolism, based on input data characterizing the forcing functions—water temperature, and food quality/quantity. The package provides a demo dataset of forcings for each species, as well as a typical set of husbandry parameters for Mediterranean conditions. The present work illustrates RAC main features, and its current capabilities/limitations. Three test cases are presented as a proof of concept of RAC applicability, and to demonstrate its potential for integrating different open products nowadays provided by remote sensing and operational oceanography. PMID:29723208

Determinants for return to work among sickness certified patients in general practice.

PubMed

von Celsing, Anna-Sophia; Svärdsudd, Kurt; Eriksson, Hans-G; Björkegren, Karin; Eriksson, Margaretha; Wallman, Thorne

2012-12-14

Long-term sickness absence is one of the main risk factors for permanent exit out of the labour market. Early identification of the condition is essential to facilitate return to work. The aim of this study was to analyse possible determinants of return to work and their relative impact. All 943 subjects aged 18 to 63 years, sickness certified at a Primary Health Care Centre in Sweden from 1 January until 31 August 2004, were followed up for three years. Baseline information on sex, age, sick leave diagnosis, employment status, extent of sick leave, and sickness absence during the year before baseline was obtained, as was information on all compensated days of sick leave, disability pension and death during follow-up. Slightly more than half the subjects were women, mean age was 39 years. Half of the study population returned to work within 14 days after baseline, and after three years only 15 subjects were still on sick leave. In multivariate proportional hazards regression analysis the extent of previous sick leave, age, being on part-time sick leave, and having a psychiatric, musculoskeletal, cardiovascular, nervous disease, digestive system, or injury or poisoning diagnosis decreased the return to work rate, while being employed increased it. Marital status, sex, being born in Sweden, citizenship, and annual salary had no influence. In logistic regression analyses across follow-up time these variables altogether explained 88-90% of return to work variation. Return to work was positively or negatively associated by a number of variables easily accessible in the GP's office. Track record data in the form of previous sick leave was the most influential variable.

Construct Validity of the Work Productivity and Activity Impairment Questionnaire across Informal Caregivers of Chronically Ill Older Patients

PubMed Central

Giovannetti, Erin R.; Wolff, Jennifer L.; Frick, Kevin D.; Boult, Chad

2011-01-01

Objectives To assess the validity of the Work Productivity and Activity Impairment questionnaire as adapted for caregiving (WPAI:CG) to measure productivity loss (hours missed from work, impairment while at work, and impairment in regular activities) due to unpaid caregiving for medically complex older adults. Methods The WPAI:CG was administered along with the Caregiver Strain Index (CSI) and Center for Epidemiologic Studies Depression Scale (CESD) to a caregiving population (N = 308) enrolled with their older, medically complex care-recipient in a cluster-randomized controlled study. Correlation coefficients were calculated between each productivity variable derived from the WPAI:CG and CSI/CESD scores. Nonparametric tests for trend across ordered groups were carried out to examine the relationship between each productivity variable and the intensity of the caregiving. Results Significant positive correlations were found between work productivity loss and caregiving-related strain (r = 0.45) and depression (r = 0.30). Measures of productivity loss were also highly associated with caregiving intensity (P < 0.05) and care-recipient medical care use (P < 0.05). The average employed caregiver reported 1.5 hours absence from work in the previous week and 18.5% reduced productivity while at work due to caregiving. Employed and nonemployed caregivers reported 27.2% reduced productivity in regular activities in the previous week. Conclusion The results indicate high convergent validity of the WPAI:CG questionnaire. This measure could facilitate research on the cost-effectiveness of caregiver-workplace interventions and provide employers and policy experts with a more accurate and comprehensive estimate of caregiving-related costs incurred by employers and society. PMID:19402853

Response to artificial drying until drought-induced death in different elevation populations of a high-mountain plant.

PubMed

García-Fernández, Alfredo; Iriondo, Jose M; Bartels, Dorothea; Escudero, Adrián

2013-01-01

Climate change is imposing warmer and more arid conditions on high-mountain Mediterranean pastures. The severity of these conditions is more intense in lower elevation populations and may be critical for their survival. In this context, we asked whether local adaptation plays an important role in the response of these populations to climate change, and if so, what mechanisms are involved. Previous works, involving reciprocal sowings suggested the existence of local adaptation in lower elevation populations of Silene ciliata, a perennial representative of high-mountain Mediterranean pastures. To determine if this local advantage is due to better adaptation to more intense water stress conditions, an experiment was conducted in which S. ciliata plants from three populations located at different elevations (Low, Intermediate and High) were subjected to severe artificial water stress. Results showed that plants from the Low population had greater tolerance to water stress than plants from the High population in the earliest stages of water shortage. Furthermore, responses of proteins to specific antibodies related to drought were evaluated. Two representative late-embryogenesis abundant (LEA) proteins known to play a role in water stress tolerance were expressed throughout the drought treatment in plants from the three populations, with some pattern differences among individuals within populations. This study detected slight evidence of local adaptation to water stress in populations from different elevations. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

Environmental Variables Explain Genetic Structure in a Beetle-Associated Nematode

PubMed Central

McGaughran, Angela; Morgan, Katy; Sommer, Ralf J.

2014-01-01

The distribution of a species is a complex expression of its ecological and evolutionary history and integrating population genetic, environmental, and ecological data can provide new insights into the effects of the environment on the population structure of species. Previous work demonstrated strong patterns of genetic differentiation in natural populations of the hermaphroditic nematode Pristionchus pacificus in its La Réunion Island habitat, but gave no clear understanding of the role of the environment in structuring this variation. Here, we present what is to our knowledge the first study to statistically evaluate the role of the environment in shaping the structure and distribution of nematode populations. We test the hypothesis that genetic structure in P. pacificus is influenced by environmental variables, by combining population genetic analyses of microsatellite data from 18 populations and 370 strains, with multivariate statistics on environmental data, and species distribution modelling. We assess and quantify the relative importance of environmental factors (geographic distance, altitude, temperature, precipitation, and beetle host) on genetic variation among populations. Despite the fact that geographic populations of P. pacificus comprise vast genetic diversity sourced from multiple ancestral lineages, we find strong evidence for local associations between environment and genetic variation. Further, we show that significantly more genetic variation in P. pacificus populations is explained by environmental variation than by geographic distances. This supports a strong role for environmental heterogeneity vs. genetic drift in the divergence of populations, which we suggest may be influenced by adaptive forces. PMID:24498073

Effect of Advanced HIV Infection on the Respiratory Microbiome.

PubMed

Twigg, Homer L; Knox, Kenneth S; Zhou, Jin; Crothers, Kristina A; Nelson, David E; Toh, Evelyn; Day, Richard B; Lin, Huaiying; Gao, Xiang; Dong, Qunfeng; Mi, Deming; Katz, Barry P; Sodergren, Erica; Weinstock, George M

2016-07-15

Previous work found the lung microbiome in healthy subjects infected with HIV was similar to that in uninfected subjects. We hypothesized the lung microbiome from subjects infected with HIV with more advanced disease would differ from that of an uninfected control population. To measure the lung microbiome in an HIV-infected population with advanced disease. 16s RNA gene sequencing was performed on acellular bronchoalveolar lavage (BAL) fluid from 30 subjects infected with HIV with advanced disease (baseline mean CD4 count, 262 cells/mm(3)) before and up to 3 years after starting highly active antiretroviral therapy (HAART) and compared with 22 uninfected control subjects. The lung microbiome in subjects infected with HIV with advanced disease demonstrated decreased alpha diversity (richness and diversity) and greater beta diversity compared with uninfected BAL. Differences improved with HAART, but still persisted up to 3 years after starting therapy. Population dispersion in the group infected with HIV was significantly greater than in the uninfected cohort and declined after treatment. There were differences in the relative abundance of some bacteria between the two groups at baseline and after 1 year of therapy. After 1 year on HAART, HIV BAL contained an increased abundance of Prevotella and Veillonella, bacteria previously associated with lung inflammation. The lung microbiome in subjects infected with HIV with advanced disease is altered compared with an uninfected population both in diversity and bacterial composition. Differences remain up to 3 years after starting HAART. We speculate an altered lung microbiome in HIV infection may contribute to chronic inflammation and lung complications seen in the HAART era.

IN-SYNC. IV. The Young Stellar Population in the Orion A Molecular Cloud

NASA Astrophysics Data System (ADS)

Da Rio, Nicola; Tan, Jonathan C.; Covey, Kevin R.; Cottaar, Michiel; Foster, Jonathan B.; Cullen, Nicholas C.; Tobin, John J.; Kim, Jinyoung S.; Meyer, Michael R.; Nidever, David L.; Stassun, Keivan G.; Chojnowski, S. Drew; Flaherty, Kevin M.; Majewski, Steve; Skrutskie, Michael F.; Zasowski, Gail; Pan, Kaike

2016-02-01

We present the results of the Sloan Digital Sky Survey APOGEE INfrared Spectroscopy of Young Nebulous Clusters program (IN-SYNC) survey of the Orion A molecular cloud. This survey obtained high-resolution near-infrared spectroscopy of about 2700 young pre-main-sequence stars on a ˜ 6^\\circ field of view. We have measured accurate stellar parameters ({T}{{eff}}, {log}g, v{sin}I) and extinctions and placed the sources in the Hertzsprung-Russel diagram (HRD). We have also extracted radial velocities for the kinematic characterization of the population. We compare our measurements with literature results to assess the performance and accuracy of the survey. Source extinction shows evidence for dust grains that are larger than those in the diffuse interstellar medium: we estimate an average RV = 5.5 in the region. Importantly, we find a clear correlation between HRD inferred ages and spectroscopic surface-gravity-inferred ages and between extinction and disk presence; this strongly suggests a real spread of ages larger than a few Myr. Focusing on the young population around NGC 1980/ι Ori, which has previously been suggested to be a separate, foreground, older cluster, we confirm its older (˜5 Myr) age and low AV, but considering that its radial velocity distribution is indistinguishable from Orion A’s population, we suggest that NGC 1980 is part of Orion A’s star formation activity. Based on their stellar parameters and kinematic properties, we identify 383 new candidate members of Orion A, most of which are diskless sources in areas of the region poorly studied by previous works.

It can work: Open employment for people with experience of mental illness.

PubMed

Peterson, Debbie; Gordon, Sarah; Neale, Jenny

2017-01-01

Previous research has tended to focus on the barriers to employment for people with mental illness and the extra support they may need. This research contributes to the knowledge base pertaining to this population by looking at successful employment relationships in New Zealand. To describe factors enabling and/or sustaining the open employment of people with experience of mental illness. Fifteen pairs of employers and employees were interviewed individually but consecutively (using a semi-structured interview schedule) about their perceptions of the critical factors that enabled and sustained the employee's employment. Employee participants were recruited by advertisement, with employers approached through their employees. Transcripts were analysed using a thematic analysis. Themes raised in the interviews included the meaning of work, disclosure of mental illness, the benefits of working, special arrangements or accommodations, the work environment and key things employers and employees do to sustain successful employment. Four critical success factors were identified relating to disclosure, the employment relationship, freedom from discrimination and workplace flexibility.

Deep sequencing analysis of viral infection and evolution allows rapid and detailed characterization of viral mutant spectrum.

PubMed

Isakov, Ofer; Bordería, Antonio V; Golan, David; Hamenahem, Amir; Celniker, Gershon; Yoffe, Liron; Blanc, Hervé; Vignuzzi, Marco; Shomron, Noam

2015-07-01

The study of RNA virus populations is a challenging task. Each population of RNA virus is composed of a collection of different, yet related genomes often referred to as mutant spectra or quasispecies. Virologists using deep sequencing technologies face major obstacles when studying virus population dynamics, both experimentally and in natural settings due to the relatively high error rates of these technologies and the lack of high performance pipelines. In order to overcome these hurdles we developed a computational pipeline, termed ViVan (Viral Variance Analysis). ViVan is a complete pipeline facilitating the identification, characterization and comparison of sequence variance in deep sequenced virus populations. Applying ViVan on deep sequenced data obtained from samples that were previously characterized by more classical approaches, we uncovered novel and potentially crucial aspects of virus populations. With our experimental work, we illustrate how ViVan can be used for studies ranging from the more practical, detection of resistant mutations and effects of antiviral treatments, to the more theoretical temporal characterization of the population in evolutionary studies. Freely available on the web at http://www.vivanbioinfo.org : nshomron@post.tau.ac.il Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press.

Microsatellite analysis of genetic divergence among populations of giant Galápagos tortoises.

PubMed

Ciofi, Claudio; Milinkovitch, Michel C; Gibbs, James P; Caccone, Adalgisa; Powell, Jeffrey R

2002-11-01

Giant Galápagos tortoises represent an interesting model for the study of patterns of genetic divergence and adaptive differentiation related to island colonization events. Recent mitochondrial DNA work elucidated the evolutionary history of the species and helped to clarify aspects of nomenclature. We used 10 microsatellite loci to assess levels of genetic divergence among and within island populations. In particular, we described the genetic structure of tortoises on the island of Isabela, where discrimination of different taxa is still subject of debate. Individual island populations were all genetically distinct. The island of Santa Cruz harboured two distinct populations. On Isabela, populations of Volcan Wolf, Darwin and Alcedo were significantly different from each other. On the other hand, Volcan Wolf showed allelic similarity with the island of Santiago. On Southern Isabela, lower genetic divergence was found between Northeast Sierra Negra and Volcan Alcedo, while patterns of gene flow were recorded among tortoises of Cerro Azul and Southeast Sierra Negra. These tortoises have endured heavy exploitation during the last three centuries and recently attracted much concern due to the current number of stochastic and deterministic threats to extant populations. Our study complements previous investigation based on mtDNA diversity and provides further information that may help devising tortoise management plans.

Psychosocial work environment factors and weight change: a prospective study among Danish health care workers.

PubMed

Gram Quist, Helle; Christensen, Ulla; Christensen, Karl Bang; Aust, Birgit; Borg, Vilhelm; Bjorner, Jakob B

2013-01-17

Lifestyle variables may serve as important intermediate factors between psychosocial work environment and health outcomes. Previous studies, focussing on work stress models have shown mixed and weak results in relation to weight change. This study aims to investigate psychosocial factors outside the classical work stress models as potential predictors of change in body mass index (BMI) in a population of health care workers. A cohort study, with three years follow-up, was conducted among Danish health care workers (3982 women and 152 men). Logistic regression analyses examined change in BMI (more than +/- 2 kg/m(2)) as predicted by baseline psychosocial work factors (work pace, workload, quality of leadership, influence at work, meaning of work, predictability, commitment, role clarity, and role conflicts) and five covariates (age, cohabitation, physical work demands, type of work position and seniority). Among women, high role conflicts predicted weight gain, while high role clarity predicted both weight gain and weight loss. Living alone also predicted weight gain among women, while older age decreased the odds of weight gain. High leadership quality predicted weight loss among men. Associations were generally weak, with the exception of quality of leadership, age, and cohabitation. This study of a single occupational group suggested a few new risk factors for weight change outside the traditional work stress models.

Deadly heat waves projected in the densely populated agricultural regions of South Asia

PubMed Central

Im, Eun-Soon; Pal, Jeremy S.; Eltahir, Elfatih A. B.

2017-01-01

The risk associated with any climate change impact reflects intensity of natural hazard and level of human vulnerability. Previous work has shown that a wet-bulb temperature of 35°C can be considered an upper limit on human survivability. On the basis of an ensemble of high-resolution climate change simulations, we project that extremes of wet-bulb temperature in South Asia are likely to approach and, in a few locations, exceed this critical threshold by the late 21st century under the business-as-usual scenario of future greenhouse gas emissions. The most intense hazard from extreme future heat waves is concentrated around densely populated agricultural regions of the Ganges and Indus river basins. Climate change, without mitigation, presents a serious and unique risk in South Asia, a region inhabited by about one-fifth of the global human population, due to an unprecedented combination of severe natural hazard and acute vulnerability. PMID:28782036

Reactive strategies in indirect reciprocity.

PubMed

Ohtsuki, Hisashi

2004-04-07

Evolution of reactive strategy of indirect reciprocity is discussed, where individuals interact with others through the one-shot Prisoner's Dilemma game, changing their partners in every round. We investigate all of the reactive strategies that are stochastic, including deterministic ones as special cases. First we study adaptive dynamics of reactive strategies by assuming monomorphic population. Results are very similar to the corresponding evolutionary dynamics of direct reciprocity. The discriminating strategy, which prescribes cooperation only with those who cooperated in the previous round, cannot be an outcome of the evolution. Next we examine the case where the population includes a diversity of strategies. We find that only the mean 'discriminatoriness' in the population is the parameter that affects the evolutionary dynamics. The discriminating strategy works as a promoter of cooperation there. However, it is again not the end point of the evolution. This is because retaliatory defection, which was prescribed by the discriminating strategy, is regarded as another defection toward the society. These results caution that we have to reconsider the role of retaliatory defection much more carefully.

Using a Cultural and RDoC Framework to Conceptualize Anxiety in Asian Americans

PubMed Central

Liu, Huiting; Lieberman, Lynne; Stevens, Elizabeth; Auerbach, Randy P.; Shankman, Stewart A.

2016-01-01

Asian Americans are one of the fastest growing minority group in the United States; however, mental health within this population segment, particularly anxiety disorders, remains significantly understudied. Both the heterogeneity within the Asian American population, along with the multidimensional nature of anxiety, contribute to difficulties in understanding anxiety in this population. The present paper will review two sources of heterogeneity within anxiety in Asian Americans: (1) cultural variables and (2) mechanisms or components of anxiety. Specifically, we will examine four cultural variables most commonly found in research related to anxiety in Asian Americans: acculturation, affect valuation, loss of face, and individualism-collectivism. We will also discuss ways to parse anxiety through a Research Domain Criteria (RDoC) framework, specifically focusing on sensitivity to acute and potential threat, constructs within the Negative Valence System. We also present previously unpublished preliminary data to illustrate one way of examining ethnic differences in anxiety using an RDoC framework. Finally, this paper offers recommendations for future work in this area. PMID:27659553

Using a cultural and RDoC framework to conceptualize anxiety in Asian Americans.

PubMed

Liu, Huiting; Lieberman, Lynne; Stevens, Elizabeth S; Auerbach, Randy P; Shankman, Stewart A

2017-05-01

Asian Americans are one of the fastest growing minority groups in the United States; however, mental health within this population segment, particularly anxiety disorders, remains significantly understudied. Both the heterogeneity within the Asian American population and the multidimensional nature of anxiety contribute to difficulties in understanding anxiety in this population. The present paper reviewed two sources of heterogeneity within anxiety in Asian Americans: (1) cultural variables and (2) mechanisms or components of anxiety. Specifically, we examined four cultural variables most commonly found in research related to anxiety in Asian Americans: acculturation, loss of face, affect valuation, and individualism-collectivism. We also discussed ways to parse anxiety through a Research Domain Criteria (RDoC) framework, specifically focusing on sensitivity to acute and potential threat, constructs within the Negative Valence System. Previously unpublished preliminary data were presented to illustrate one way of examining ethnic differences in anxiety using an RDoC framework. Finally, this paper offered recommendations for future work in this area. Copyright © 2016 Elsevier Ltd. All rights reserved.

Computing by robust transience: How the fronto-parietal network performs sequential category-based decisions

PubMed Central

Chaisangmongkon, Warasinee; Swaminathan, Sruthi K.; Freedman, David J.; Wang, Xiao-Jing

2017-01-01

Summary Decision making involves dynamic interplay between internal judgements and external perception, which has been investigated in delayed match-to-category (DMC) experiments. Our analysis of neural recordings shows that, during DMC tasks, LIP and PFC neurons demonstrate mixed, time-varying, and heterogeneous selectivity, but previous theoretical work has not established the link between these neural characteristics and population-level computations. We trained a recurrent network model to perform DMC tasks and found that the model can remarkably reproduce key features of neuronal selectivity at the single-neuron and population levels. Analysis of the trained networks elucidates that robust transient trajectories of the neural population are the key driver of sequential categorical decisions. The directions of trajectories are governed by network self-organized connectivity, defining a ‘neural landscape’, consisting of a task-tailored arrangement of slow states and dynamical tunnels. With this model, we can identify functionally-relevant circuit motifs and generalize the framework to solve other categorization tasks. PMID:28334612

Particle Acceleration in a Statistically Modeled Solar Active-Region Corona

NASA Astrophysics Data System (ADS)

Toutounzi, A.; Vlahos, L.; Isliker, H.; Dimitropoulou, M.; Anastasiadis, A.; Georgoulis, M.

2013-09-01

Elaborating a statistical approach to describe the spatiotemporally intermittent electric field structures formed inside a flaring solar active region, we investigate the efficiency of such structures in accelerating charged particles (electrons). The large-scale magnetic configuration in the solar atmosphere responds to the strong turbulent flows that convey perturbations across the active region by initiating avalanche-type processes. The resulting unstable structures correspond to small-scale dissipation regions hosting strong electric fields. Previous research on particle acceleration in strongly turbulent plasmas provides a general framework for addressing such a problem. This framework combines various electromagnetic field configurations obtained by magnetohydrodynamical (MHD) or cellular automata (CA) simulations, or by employing a statistical description of the field's strength and configuration with test particle simulations. Our objective is to complement previous work done on the subject. As in previous efforts, a set of three probability distribution functions describes our ad-hoc electromagnetic field configurations. In addition, we work on data-driven 3D magnetic field extrapolations. A collisional relativistic test-particle simulation traces each particle's guiding center within these configurations. We also find that an interplay between different electron populations (thermal/non-thermal, ambient/injected) in our simulations may also address, via a re-acceleration mechanism, the so called `number problem'. Using the simulated particle-energy distributions at different heights of the cylinder we test our results against observations, in the framework of the collisional thick target model (CTTM) of solar hard X-ray (HXR) emission. The above work is supported by the Hellenic National Space Weather Research Network (HNSWRN) via the THALIS Programme.

Multiple Genetic Associations with Irish Wolfhound Dilated Cardiomyopathy.

PubMed

Simpson, Siobhan; Dunning, Mark D; Brownlie, Serena; Patel, Janika; Godden, Megan; Cobb, Malcolm; Mongan, Nigel P; Rutland, Catrin S

2016-01-01

Cardiac disease is a leading cause of morbidity and mortality in dogs and humans, with dilated cardiomyopathy being a large contributor to this. The Irish Wolfhound (IWH) is one of the most commonly affected breeds and one of the few breeds with genetic loci associated with the disease. Mutations in more than 50 genes are associated with human dilated cardiomyopathy (DCM), yet very few are also associated with canine DCM. Furthermore, none of the identified canine loci explain many cases of the disease and previous work has indicated that genotypes at multiple loci may act together to influence disease development. In this study, loci previously associated with DCM in IWH were tested for associations in a new cohort both individually and in combination. We have identified loci significantly associated with the disease individually, but no genotypes individually or in pairs conferred a significantly greater risk of developing DCM than the population risk. However combining three loci together did result in the identification of a genotype which conferred a greater risk of disease than the overall population risk. This study suggests multiple rather than individual genetic factors, cooperating to influence DCM risk in IWH.

Multiple Genetic Associations with Irish Wolfhound Dilated Cardiomyopathy

PubMed Central

Dunning, Mark D.; Brownlie, Serena

2016-01-01

Cardiac disease is a leading cause of morbidity and mortality in dogs and humans, with dilated cardiomyopathy being a large contributor to this. The Irish Wolfhound (IWH) is one of the most commonly affected breeds and one of the few breeds with genetic loci associated with the disease. Mutations in more than 50 genes are associated with human dilated cardiomyopathy (DCM), yet very few are also associated with canine DCM. Furthermore, none of the identified canine loci explain many cases of the disease and previous work has indicated that genotypes at multiple loci may act together to influence disease development. In this study, loci previously associated with DCM in IWH were tested for associations in a new cohort both individually and in combination. We have identified loci significantly associated with the disease individually, but no genotypes individually or in pairs conferred a significantly greater risk of developing DCM than the population risk. However combining three loci together did result in the identification of a genotype which conferred a greater risk of disease than the overall population risk. This study suggests multiple rather than individual genetic factors, cooperating to influence DCM risk in IWH. PMID:28070514

Estimation of tiger densities in India using photographic captures and recaptures

USGS Publications Warehouse

Karanth, U.; Nichols, J.D.

1998-01-01

Previously applied methods for estimating tiger (Panthera tigris) abundance using total counts based on tracks have proved unreliable. In this paper we use a field method proposed by Karanth (1995), combining camera-trap photography to identify individual tigers based on stripe patterns, with capture-recapture estimators. We developed a sampling design for camera-trapping and used the approach to estimate tiger population size and density in four representative tiger habitats in different parts of India. The field method worked well and provided data suitable for analysis using closed capture-recapture models. The results suggest the potential for applying this methodology for estimating abundances, survival rates and other population parameters in tigers and other low density, secretive animal species with distinctive coat patterns or other external markings. Estimated probabilities of photo-capturing tigers present in the study sites ranged from 0.75 - 1.00. The estimated mean tiger densities ranged from 4.1 (SE hat= 1.31) to 11.7 (SE hat= 1.93) tigers/100 km2. The results support the previous suggestions of Karanth and Sunquist (1995) that densities of tigers and other large felids may be primarily determined by prey community structure at a given site.

Novel Synthetic Medea selfish genetic elements drive population replacement in Drosophila, and a theoretical exploration of Medea-dependent population suppression

PubMed Central

Akbari, Omar S.; Chen, Chun-Hong; Marshall, John M.; Huang, Haixia; Antoshechkin, Igor; Hay, Bruce A.

2013-01-01

Insects act as vectors for diseases of plants, animals and humans. Replacement of wild insect populations with genetically modified individuals unable to transmit disease provides a potentially self-perpetuating method of disease prevention. Population replacement requires a gene drive mechanism in order to spread linked genes mediating disease refractoriness through wild populations. We previously reported the creation of synthetic Medea selfish genetic elements able to drive population replacement in Drosophila. These elements use microRNA-mediated silencing of myd88, a maternally expressed gene required for embryonic dorso-ventral pattern formation, coupled with early zygotic expression of a rescuing transgene, to bring about gene drive. Medea elements that work through additional mechanisms are needed in order to be able to carry out cycles of population replacement and/or remove existing transgenes from the population, using second-generation elements that spread while driving first-generation elements out of the population. Here we report the synthesis and population genetic behavior of two new synthetic Medea elements that drive population replacement through manipulation of signaling pathways involved in cellular blastoderm formation or Notch signaling, demonstrating that in Drosophila Medea elements can be generated through manipulation of diverse signaling pathways. We also describe the mRNA and small RNA changes in ovaries and early embryos associated from Medea-bearing females. Finally, we use modeling to illustrate how Medea elements carrying genes that result in diapause-dependent female lethality could be used to bring about population suppression. PMID:23654248

Anthropogenic Sulphur Dioxide Load over China as Observed from Different Satellite Sensors

NASA Technical Reports Server (NTRS)

Koukouli, M. E.; Balis, D. S.; Johannes Van Der A, Ronald; Theys, N.; Hedelt, P.; Richter, A.; Krotkov, N.; Li, Can; Taylor, M.

2016-01-01

China, with its rapid economic growth and immense exporting power, has been the focus of many studies during this previous decade quantifying its increasing emissions contribution to the Earth's atmosphere. With a population slowly shifting towards enlarged power and purchasing needs, the ceaseless inauguration of new power plants, smelters, refineries and industrial parks leads infallibly to increases in sulphur dioxide, SO2, emissions. The recent capability of next generation algorithms as well as new space-borne instruments to detect anthropogenic SO2 loads has enabled a fast advancement in this field. In the following work, algorithms providing total SO2 columns over China based on SCIAMACHY/Envisat, OMI/Aura and GOME2/MetopA observations are presented. The need for post-processing and gridding of the SO2 fields is further revealed in this work, following the path of previous publications. Further, it is demonstrated that the usage of appropriate statistical tools permits studying parts of the datasets typically excluded, such as the winter months loads. Focusing on actual point sources, such as megacities and known power plant locations, instead of entire provinces, monthly mean time series have been examined in detail. The sharp decline in SO2 emissions in more than 90% - 95% of the locations studied confirms the recent implementation of government desulphurisation legislation; however, locations with increases, even for the previous five years, are also identified. These belong to provinces with emerging economies which are in haste to install power plants and are possibly viewed leniently by the authorities, in favour of growth. The SO2 load seasonality has also been examined in detail with a novel mathematical tool, with 70% of the point sources having a statistically significant annual cycle with highs in winter and lows in summer, following the heating requirements of the Chinese population.

Anthropogenic sulphur dioxide load over China as observed from different satellite sensors

NASA Astrophysics Data System (ADS)

Koukouli, M. E.; Balis, D. S.; van der A, Ronald Johannes; Theys, N.; Hedelt, P.; Richter, A.; Krotkov, N.; Li, C.; Taylor, M.

2016-11-01

China, with its rapid economic growth and immense exporting power, has been the focus of many studies during this previous decade quantifying its increasing emissions contribution to the Earth's atmosphere. With a population slowly shifting towards enlarged power and purchasing needs, the ceaseless inauguration of new power plants, smelters, refineries and industrial parks leads infallibly to increases in sulphur dioxide, SO2, emissions. The recent capability of next generation algorithms as well as new space-borne instruments to detect anthropogenic SO2 loads has enabled a fast advancement in this field. In the following work, algorithms providing total SO2 columns over China based on SCIAMACHY/Envisat, OMI/Aura and GOME2/MetopA observations are presented. The need for post-processing and gridding of the SO2 fields is further revealed in this work, following the path of previous publications. Further, it is demonstrated that the usage of appropriate statistical tools permits studying parts of the datasets typically excluded, such as the winter months loads. Focusing on actual point sources, such as megacities and known power plant locations, instead of entire provinces, monthly mean time series have been examined in detail. The sharp decline in SO2 emissions in more than 90%-95% of the locations studied confirms the recent implementation of government desulphurisation legislation; however, locations with increases, even for the previous five years, are also identified. These belong to provinces with emerging economies which are in haste to install power plants and are possibly viewed leniently by the authorities, in favour of growth. The SO2 load seasonality has also been examined in detail with a novel mathematical tool, with 70% of the point sources having a statistically significant annual cycle with highs in winter and lows in summer, following the heating requirements of the Chinese population.

Nightmares: Risk Factors Among the Finnish General Adult Population

PubMed Central

Sandman, Nils; Valli, Katja; Kronholm, Erkki; Revonsuo, Antti; Laatikainen, Tiina; Paunio, Tiina

2015-01-01

Study Objectives: To identify risk factors for experiencing nightmares among the Finnish general adult population. The study aimed to both test whether previously reported correlates of frequent nightmares could be reproduced in a large population sample and to explore previously unreported associations. Design: Two independent cross-sectional population surveys of the National FINRISK Study. Setting: Age- and sex-stratified random samples of the Finnish population in 2007 and 2012. Participants: A total of 13,922 participants (6,515 men and 7,407 women) aged 25–74 y. Interventions: N/A. Measurements and results: Nightmare frequency as well as several items related to socioeconomic status, sleep, mental well-being, life satisfaction, alcohol use, medication, and physical well-being were recorded with a questionnaire. In multinomial logistic regression analysis, a depression-related negative attitude toward the self (odds ratio [OR] 1.32 per 1-point increase), insomnia (OR 6.90), and exhaustion and fatigue (OR 6.86) were the strongest risk factors for experiencing frequent nightmares (P < 0.001 for all). Sex, age, a self-reported impaired ability to work, low life satisfaction, the use of antidepressants or hypnotics, and frequent heavy use of alcohol were also strongly associated with frequent nightmares (P < 0.001 for all). Conclusions: Symptoms of depression and insomnia were the strongest predictors of frequent nightmares in this dataset. Additionally, a wide variety of factors related to psychological and physical well-being were associated with nightmare frequency with modest effect sizes. Hence, nightmare frequency appears to have a strong connection with sleep and mood problems, but is also associated with a variety of measures of psychological and physical well-being. Citation: Sandman N, Valli K, Kronholm E, Revonsuo A, Laatikainen T, Paunio T. Nightmares: risk factors among the finnish general adult population. SLEEP 2015;38(4):507–514. PMID:25325474

Confounding environmental colour and distribution shape leads to underestimation of population extinction risk.

PubMed

Fowler, Mike S; Ruokolainen, Lasse

2013-01-01

The colour of environmental variability influences the size of population fluctuations when filtered through density dependent dynamics, driving extinction risk through dynamical resonance. Slow fluctuations (low frequencies) dominate in red environments, rapid fluctuations (high frequencies) in blue environments and white environments are purely random (no frequencies dominate). Two methods are commonly employed to generate the coloured spatial and/or temporal stochastic (environmental) series used in combination with population (dynamical feedback) models: autoregressive [AR(1)] and sinusoidal (1/f) models. We show that changing environmental colour from white to red with 1/f models, and from white to red or blue with AR(1) models, generates coloured environmental series that are not normally distributed at finite time-scales, potentially confounding comparison with normally distributed white noise models. Increasing variability of sample Skewness and Kurtosis and decreasing mean Kurtosis of these series alter the frequency distribution shape of the realised values of the coloured stochastic processes. These changes in distribution shape alter patterns in the probability of single and series of extreme conditions. We show that the reduced extinction risk for undercompensating (slow growing) populations in red environments previously predicted with traditional 1/f methods is an artefact of changes in the distribution shapes of the environmental series. This is demonstrated by comparison with coloured series controlled to be normally distributed using spectral mimicry. Changes in the distribution shape that arise using traditional methods lead to underestimation of extinction risk in normally distributed, red 1/f environments. AR(1) methods also underestimate extinction risks in traditionally generated red environments. This work synthesises previous results and provides further insight into the processes driving extinction risk in model populations. We must let the characteristics of known natural environmental covariates (e.g., colour and distribution shape) guide us in our choice of how to best model the impact of coloured environmental variation on population dynamics.

Standardized assessment of psychosocial factors and their influence on medically confirmed health outcomes in workers: a systematic review.

PubMed

Rosário, Susel; Fonseca, João A; Nienhaus, Albert; da Costa, José Torres

2016-01-01

Previous studies of psychosocial work factors have indicated their importance for workers' health. However, to what extent health problems can be attributed to the nature of the work environment or other psychosocial factors is not clear. No previous systematic review has used inclusion criteria based on specific medical evaluation of work-related health outcomes and the use of validated instruments for the assessment of the psychosocial (work) environment. The aim of this systematic review is to summarize the evidence assessing the relationship between the psychosocial work environment and workers' health based on studies that used standardized and validated instruments to assess the psychosocial work environment and that focused on medically confirmed health outcomes. A systematic review of the literature was carried out by searching the databases PubMed, B-ON, Science Direct, Psycarticles, Psychology and Behavioral Sciences Collection and the search engine (Google Scholar) using appropriate words for studies published from 2004 to 2014. This review follows the recommendations of the Statement for Reporting Systematic Reviews (PRISMA). Studies were included in the review if data on psychosocial validated assessment method(s) for the study population and specific medical evaluation of health-related work outcome(s) were presented. In total, the search strategy yielded 10,623 references, of which 10 studies (seven prospective cohort and three cross-sectional) met the inclusion criteria. Most studies (7/10) observed an adverse effect of poor psychosocial work factors on workers' health: 3 on sickness absence, 4 on cardiovascular diseases. The other 3 studies reported detrimental effects on sleep and on disease-associated biomarkers. A more consistent effect was observed in studies of higher methodological quality that used a prospective design jointly with the use of validated instruments for the assessment of the psychosocial (work) environment and clinical evaluation. More prospective studies are needed to assess the evidence of work-related psychosocial factors on workers´ health.

A simulation analysis to characterize the dynamics of vaccinating behaviour on contact networks.

PubMed

Perisic, Ana; Bauch, Chris T

2009-05-28

Human behavior influences infectious disease transmission, and numerous "prevalence-behavior" models have analyzed this interplay. These previous analyses assumed homogeneously mixing populations without spatial or social structure. However, spatial and social heterogeneity are known to significantly impact transmission dynamics and are particularly relevant for certain diseases. Previous work has demonstrated that social contact structure can change the individual incentive to vaccinate, thus enabling eradication of a disease under a voluntary vaccination policy when the corresponding homogeneous mixing model predicts that eradication is impossible due to free rider effects. Here, we extend this work and characterize the range of possible behavior-prevalence dynamics on a network. We simulate transmission of a vaccine-preventable infection through a random, static contact network. Individuals choose whether or not to vaccinate on any given day according to perceived risks of vaccination and infection. We find three possible outcomes for behavior-prevalence dynamics on this type of network: small final number vaccinated and final epidemic size (due to rapid control through voluntary ring vaccination); large final number vaccinated and significant final epidemic size (due to imperfect voluntary ring vaccination), and little or no vaccination and large final epidemic size (corresponding to little or no voluntary ring vaccination). We also show that the social contact structure enables eradication under a broad range of assumptions, except when vaccine risk is sufficiently high, the disease risk is sufficiently low, or individuals vaccinate too late for the vaccine to be effective. For populations where infection can spread only through social contact network, relatively small differences in parameter values relating to perceived risk or vaccination behavior at the individual level can translate into large differences in population-level outcomes such as final size and final number vaccinated. The qualitative outcome of rational, self interested behaviour under a voluntary vaccination policy can vary substantially depending on interactions between social contact structure, perceived vaccine and disease risks, and the way that individual vaccination decision-making is modelled.

Associations between comorbid anxiety, diabetes control, and overall medical burden in a population with serious mental illness and diabetes

PubMed Central

Bajor, Laura A.; Gunzler, Douglas; Einstadter, Douglas; Thomas, Charles; McCormick, Dick; Perzynski, Adam T.; Kanuch, Stephanie; Cassidy, Kristin; Dawson, Neal V.; Sajatovic, Martha

2015-01-01

Objective While previous work has demonstrated elevation of both comorbid anxiety disorders and diabetes mellitus type II (DM2) in individuals with Serious Mental Illness (SMI), little is known regarding the impact of comorbid anxiety on DM2 outcomes in SMI populations. We analyzed baseline data from a population of SMI patients with DM2 to study relationships between comorbid anxiety, glucose control as measured by HbA1c score, and overall illness burden. Methods Using baseline data from an ongoing prospective treatment study involving 157 individuals with SMI and DM2 we compared individuals with and without a comorbid anxiety disorder and compared HbA1c levels between these groups to assess the relationship between anxiety and management of DM2. We conducted a similar analysis using cumulative number of anxiety diagnoses as a proxy for anxiety load. Finally, we searched for associations between anxiety and overall medical illness burden as measured by Charlson score. Results Anxiety disorders were seen in 33.1 % (N= 52) of individuals with SMI and DM2 and were associated with increased severity of depressive symptoms and decreased function. HbA1c levels were not significantly different in those with or without anxiety and having multiple anxiety disorders was not associated with differences in DM2 control. However, depressive symptoms were significantly associated with higher HbA1c levels. Neither comorbid anxiety nor anxiety load were significantly associated with overall medical burden. Conclusion One in 3 people with SMI and DM2 have anxiety. Depressive symptoms were significantly associated with Hb1Ac levels while anxiety symptoms had no relation to HbA1c; this is consistent with previously published work. More studies are needed to better understand the relationship between depression, anxiety and health management in people with SMI and DM2. PMID:26060262

Evaluation of an early warning system for glacial lake outburst flood (GLOF) events in Huaraz, Peru

NASA Astrophysics Data System (ADS)

McKinney, D. C.; Somos-Valenzuela, M. A.

2014-12-01

People in Cordillera Blanca range in Peru have a long history dealing with natural disasters associated to high mountains; particularly Glacier Lakes Outburst Flood (GLOF). Examples in the Cordillera Blanca vary from a GLOF that occurred in 1941 that killed more than 5000 people in the city of Huaraz to recent events from Lake Artison Baja in 2012 and Lake 513 on 2010, which were not devastating thanks to safety systems previously installed in those lakes. However, glaciers continue melting leaving new lakes or changing the characteristics of lakes that were previously controlled making safety systems obsolete that worked successfully in the past protecting communities downstream. Lake Palcacocha has evolved from being safe after the installation of a safety system in 1970 to an imminent source of GLOF risk due to the expansion that has occurred during the last 40 years increasing from a volume of 500,000 to 17 million m3. In response to this risk the community in Huaraz is planning an Early Warning System (EWS) that will allow the population to mobilize to a safe area in case a GLOF occurs. In this work we present an adaptation of the LifeSIM model to calculate the benefits from such an EWS using 2007 census data and a FLO-2D flood simulation model. The outputs are the number of people in Huaraz that could lose their life due to a GLOF. Our results indicate that without an EWS around 19,773 people could lose their life; whereas, if an EWS is installed the number of victims reduces to 7344. Finally, if mobilization of the affected population is improved the value reduces to 2865. The results show the importance of the EWS as well as informing and training the population to how to react if a GLOF occurs.

A simulation analysis to characterize the dynamics of vaccinating behaviour on contact networks

PubMed Central

2009-01-01

Background Human behavior influences infectious disease transmission, and numerous "prevalence-behavior" models have analyzed this interplay. These previous analyses assumed homogeneously mixing populations without spatial or social structure. However, spatial and social heterogeneity are known to significantly impact transmission dynamics and are particularly relevant for certain diseases. Previous work has demonstrated that social contact structure can change the individual incentive to vaccinate, thus enabling eradication of a disease under a voluntary vaccination policy when the corresponding homogeneous mixing model predicts that eradication is impossible due to free rider effects. Here, we extend this work and characterize the range of possible behavior-prevalence dynamics on a network. Methods We simulate transmission of a vaccine-prevetable infection through a random, static contact network. Individuals choose whether or not to vaccinate on any given day according to perceived risks of vaccination and infection. Results We find three possible outcomes for behavior-prevalence dynamics on this type of network: small final number vaccinated and final epidemic size (due to rapid control through voluntary ring vaccination); large final number vaccinated and significant final epidemic size (due to imperfect voluntary ring vaccination), and little or no vaccination and large final epidemic size (corresponding to little or no voluntary ring vaccination). We also show that the social contact structure enables eradication under a broad range of assumptions, except when vaccine risk is sufficiently high, the disease risk is sufficiently low, or individuals vaccinate too late for the vaccine to be effective. Conclusion For populations where infection can spread only through social contact network, relatively small differences in parameter values relating to perceived risk or vaccination behavior at the individual level can translate into large differences in population-level outcomes such as final size and final number vaccinated. The qualitative outcome of rational, self interested behaviour under a voluntary vaccination policy can vary substantially depending on interactions between social contact structure, perceived vaccine and disease risks, and the way that individual vaccination decision-making is modelled. PMID:19476616

Work disability and depressive disorders: impact on the European population.

PubMed

Veronese, Antonio; Ayuso-Mateos, José Luis; Cabello, Maria; Chatterji, Somnath; Nuevo, Roberto

2012-02-01

Our aim was to study the impact of depressive disorders on work disability to discover the determinants of depression for work disability in the European countries. The sample was composed of 31,126 individuals from 29 countries included in the 2002 World Health Survey of the World Health Organization. National representative samples of countries from all regions of Europe and with different levels of economic development and health coverage were selected. Estimates of people not working because of ill health did not differ among European countries in relation to levels of economic development or health coverage. Significant determinants of people with diagnosis of depression not working because of ill health (reference category) versus working were age (odds ratio = 0.97), female sex (odds ratio = 1.71), education (odds ratio = 1.11), marital status (being unmarried indicating less probability), lowest income level, and comorbidity with angina pectoris (odds ratio = 0.51). Moreover, according to previous studies, we found some determinants (comorbidity with other diseases, young age, and unemployment) impacting on health status. Depression is a substantial cause of work disability and it is a complex phenomenon that involves many variables. Investigation into this relationship should improve, focusing on the role of determinants.

Investigation of the relationship between convenient visits and doctors' fatigue using burnout and work engagement scales.

PubMed

Matsumoto, Yuuki; Hoshiko, Michiko; Morimatsu, Yoshitaka; Mori, Mihoko; Kushino, Nanae; Ishitake, Tatsuya

2015-01-01

Fatigue caused by high workload is often responsible for the high attrition among doctors, and has contributed to a disruption in community medicine. In order to address this problem, institutional mechanisms at the hospital level are required. Previous studies have shown that systemic measures at the hospital level and a change in the mindset of patients can help manage the problem. "Convenient visits" refer to emergency visits for non-emergency problems. It is an avoidable cause of high workload on doctors. Convenient visits also refer to emergency consultation for non-emergency symptoms. As this is a new phenomenon, its relationship with doctors' fatigue needs further research. We investigated the relationship between convenient visits and doctors' fatigue using burnout and work engagement scales. We selected 44 hospitals, with >200 beds each, in provincial cities of prefectures with a doctor-population ratio lower than the national average. These cities were considered likely to manifest the phenomenon of 24-hour society and include overworked doctors. Ordinance-designated cities were excluded from this study owing to wide population variability. Three doctors from each hospital were randomly selected from among physicians, surgeons, and pediatricians. We distributed questionnaires (a questionnaire concerning convenient visits, Maslach Burnout Inventory-Human Services Survey, and Utrecht Work Engagement Scale) to 132 doctors. Forty-two doctors responded to the survey. The median proportion of convenient visits among emergency visits was 50%. Sixty percent of the doctors surveyed were annoyed by convenient visits. Other doctors indicated good collaboration between the hospitals and communities or that they were not currently annoyed by convenient visits, although they had been annoyed previously. The emotional exhaustion in doctors, who worked in hospitals that did not restrict convenient visits, was significantly higher than in those who worked in hospitals that restricted these visits. A significant risk of serious burnout was found via crude and multiple logistic regression analysis (adjusted for age and gender, or adjusted for age, gender, clinical department, frequency of work shifts, and sleep duration during work shifts). Doctors working in hospitals that do not protect them against convenient visits are more prone to burnout. Although the number of convenient visitors is increasing, many hospitals lack systemic measures to manage them. This contributes to doctors' burnout. We suggest that hospitals control convenient visits for preventing doctors' burnout. Collaboration between hospitals and communities is required to help alleviate this problem.

A Lead User Approach to Universal Design - Involving Older Adults in the Design Process.

PubMed

Raviselvam, Sujithra; Wood, Kristin L; Hölttä-Otto, Katja; Tam, Victoria; Nagarajan, Kamya

2016-01-01

The concept of Universal Design has received increasing appreciation over the past two decades. Yet, there are very few existing designs that cater to the needs of extraordinary users who experience some form of physical challenge. Previous work has shown promising results on involving users with physical challenges as lead users - users who have the potential to identify needs that could be latent among the general population. It has also been shown that older adults can act as such lead users. They can help design universal product ideas that satisfy both older adults and the general population. In this paper we build on this and examine if involving older adults in the design phase can result in universal products, products preferred by both older adults and the general population over a current option. Eighty-nine older adult participants and thirty-four general population participants took part in the study. Products were redesigned and prototyped based on the needs of older adults and tested among both populations. Results show that, although older adults and the general population did share certain needs and demands, the majority of older adults had needs and demands that were different from those of the general population. However, even though the needs differed between the populations, on average 89% of the general population participants preferred products designed based on design needs expressed by older adults over the current option. This provides further evidence supporting the use of older adults in designing products for all.

The PILI@Work Program: a translation of the diabetes prevention program to Native Hawaiian-serving worksites in Hawai'i.

PubMed

Townsend, Claire K M; Miyamoto, Robin E S; Antonio, Mapuana; Zhang, Guangxing; Paloma, Diane; Basques, DeAnna; Braun, Kathryn L; Kaholokula, Joseph Keawe'aimoku

2016-06-01

A previously translated Diabetes Prevention Program Lifestyle Intervention (DPP-LI) was adapted for delivery as a worksite-based intervention, called PILI@Work, to address obesity disparities in Native Hawaiians/Pacific Islanders. This study examined the effectiveness of PILI@Work and factors associated with weight loss at post-intervention. Overweight/obese employees of 15 Native Hawaiian-serving organizations received the 3-month component of PILI@Work. Assessments included weight, systolic/diastolic blood pressure, physical activity and functioning, fat intake, locus of weight control, social support, and self-efficacy. Weight, systolic/diastolic blood pressure, physical functioning, physical activity frequency, fat intake, family support, and eating self-efficacy improved from pre- to post-intervention. Regression analysis indicated that worksite type, decreased diastolic blood pressure, increased physical activity, and more internalized locus of weight control were significantly associated with 3-month weight loss. PILI@Work initiated weight loss in Native Hawaiians/Pacific Islanders. DPP-LI translated to worksite settings and tailored for specific populations can be effective for addressing obesity.

Enterprise size and return to work after stroke.

PubMed

Hannerz, Harald; Ferm, Linnea; Poulsen, Otto M; Pedersen, Betina Holbæk; Andersen, Lars L

2012-12-01

It has been hypothesised that return to work rates among sick-listed workers increases with enterprise size. The aim of the present study was to estimate the effect of enterprise size on the odds of returning to work among previously employed stroke patients in Denmark, 2000-2006. We used a prospective design with a 2 year follow-up period. The study population consisted of 13,178 stroke patients divided into four enterprise sizes categories, according to the place of their employment prior to the stroke: micro (1-9 employees), small (10-49 employees), medium (50-249 employees) and large (>250 employees). The analysis was based on nationwide data on enterprise size from Statistics Denmark merged with data from the Danish occupational hospitalisation register. We found a statistically significant association (p = 0.034); each increase in enterprise size category was followed by an increase in the estimated odds of returning to work. The chances of returning to work after stroke increases as the size of enterprise increases. Preventive efforts and research aimed at finding ways of mitigating the effect are warranted.

Registry-based analysis of participator representativeness: a source of concern for sickness absence research?

PubMed

Knapstad, Marit; Löve, Jesper; Holmgren, Kristina; Hensing, Gunnel; Øverland, Simon

2016-10-21

Selective participation can bias results in epidemiological surveys. The importance of health status is often suggested as a possible explanation for non-participation but few empirical studies exist. In a population-based study, explicitly focused on sickness absence, health and work, we examined whether a history of high levels of sickness absence was associated with non-participation. The study is based on data from official sickness absence registers from participants, non-participants and the total target population of the baseline survey of the Health Assets Project (HAP). HAP is a population-based cohort study in the Västra Götaland region in South Western Sweden. HAP included a random population cohort (n=7984) and 2 cohorts with recent sickness absence (employees (n=6140) and non-employees (n=990)), extracted from the same overall general working-age population. We examined differences in participation rates between cohorts (2008), and differences in previous sickness absence (2001-2008) between participants (individual-level data) and non-participants or the target population (group-level data) within cohorts. Participants had statistically significant less registered sickness absence in the past than non-participants and the target population for some, but not all, of the years analysed. Yet these differences were not of substantial size. Other factors than sickness absence were more important in explaining differences in participation, whereby participants were more likely to be women, older, born in Nordic countries, married and have higher incomes than non-participants. Although specifically addressing sickness absence, having such experience did not add any substantial layer to selective participation in the present survey. Detailed measures are needed to gain a better understanding for health selection in health-related surveys such as those addressing sickness absence, for instance in order to discriminate between selection due to ability or motivation for participation. 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/.

To breathe or fight? Siamese fighting fish differ when facing a real opponent or mirror image.

PubMed

Arnott, Gareth; Beattie, Emma; Elwood, Robert W

2016-08-01

Displays are a feature of animal contest behaviour and have been interpreted as a means of gathering information on opponent fighting ability, as well as signalling aggressive motivation. In fish, contest displays often include frontal and lateral elements, which in the latter involves contestants showing their flanks to an opponent. Previous work in a range of fish species has demonstrated population-level lateralization of these displays, preferentially showing one side to their opponent. Mirrors are commonly used in place of a real opponent to study aggression in fish, yet they may disrupt the normal pattern of display behaviour. Here, using Siamese fighting fish, Betta splendens, we compare the aggressive behaviour of males to a mirror image and real opponent behind a transparent barrier. As this species is a facultative air-breather, we also quantify surface breathing, providing insights into underlying fight motivation. Consistent with previous work, we found evidence of population-level lateralization, with a bias to present the left side and use the left eye when facing a real opponent. Contrary to expectations, there were no differences in the aggressive displays to a mirror and real opponent, with positive correlations between the behaviour in the two scenarios. However, there were important differences in surface breathing, which was more frequent and of longer duration in the mirror treatment. The reasons for these differences are discussed in relation to the repertoire of contest behaviour and motivation when facing a real opponent. Copyright © 2016 Elsevier B.V. All rights reserved.

Work-Related Injury and Management Strategies Among Certified Athletic Trainers.

PubMed

Kucera, Kristen L; Lipscomb, Hester J; Roos, Karen G; Dement, John M; Hootman, Jennifer M

2018-06-13

  Health care workers have high rates of musculoskeletal injuries, but many of these injuries go unreported to workers' compensation and national surveillance systems. Little is known regarding the work-related injuries of certified athletic trainers (ATs).   To determine the 12-month incidence and prevalence of work-related injuries and describe injury-reporting and -management strategies.   Cross-sectional study.   Population-based online survey.   Of the 29 051 ATs currently certified by the Board of Certification, Inc, who "opted in" to research studies, we randomly selected 10 000. Of these, 1826 (18.3%) ATs currently working in the clinical setting were eligible and participated in the baseline survey.   An online survey was e-mailed in May of 2012. We assessed self-reported work-related injuries in the previous 12 months and management strategies including medical care, work limitations or modifications, and time off work. Statistics (frequencies and percentages) were calculated to describe injury rates per 200 000 work hours, injury prevalence, injury characteristics, and injury-reporting and -management strategies.   A total of 247 ATs reported 419 work-related injuries during the previous 12 months, for an incidence rate of 21.6 per 200 000 hours (95% confidence interval [CI] = 19.6, 23.7) and injury prevalence of 13.5% (95% CI = 12.0%, 15.1%). The low back (26%), hand/fingers (9%), and knee (9%) were frequently affected body sites. Injuries were most often caused by bodily motion/overexertion/repetition (52%), contact with objects/equipment/persons (24%), or slips/trips/falls (15%). More than half of injured ATs (55.5%) sought medical care; 25% missed work, and most (77%) did not file a workers' compensation claim for their injury. Half of injured ATs were limited at work (n = 125), and 89% modified or changed their athletic training work as a result of the injury.   More than half of AT work-related injuries required medical care or work limitations and were not reported for workers' compensation. Understanding how ATs care for and manage their work-related injuries is important given that few take time off work.

Use of non-alpine anthropogenic habitats by American pikas (Ochotona princeps) in western Oregon, USA

USGS Publications Warehouse

Manning, Tom; Hagar, Joan C.

2011-01-01

The American pika (Ochotona princeps Richardson) has long been characterized in field guides and popular literature as an obligate inhabitant of alpine talus and as having relatively low dispersal capability. However, recent work reveals pikas to have broader habitat associations than previously reported. Over a large portion of the western slope of the Cascade Range in Oregon, pikas inhabit relatively low-elevation sites far from alpine areas and frequently occur in rocky man-made habitats such as roadcuts or rock quarries. We present observations of pikas in these previously overlooked habitats and discuss implications for (1) the proposed listing of the American pika as an endangered or threatened species; (2) furthering our understanding of pika population dynamics, habitat associations, and dispersal capabilites; and (3) management of federal, state, and private forest lands.

Child Safety Reference Frameworks: a Policy Tool for Child Injury Prevention at the Sub-national Level.

PubMed

Scholtes, Beatrice; Schröder-Bäck, Peter; Mackay, Morag; Vincenten, Joanne; Brand, Helmut

2017-06-01

The aim of this paper is to present the Child Safety Reference Frameworks (CSRF), a policy advice tool that places evidence-based child safety interventions, applicable at the sub-national level, into a framework resembling the Haddon Matrix. The CSRF is based on work done in previous EU funded projects, which we have adapted to the field of child safety. The CSRF were populated following a literature review. Four CSRF were developed for four domains of child safety: road, water and home safety, and intentional injury prevention. The CSRF can be used as a reference, assessment and comparative tool by child safety practitioners and policy makers working at the sub-national level. Copyright© by the National Institute of Public Health, Prague 2017

Cell separation by immunoaffinity partitioning with polyethylene glycol-modified Protein A in aqueous polymer two-phase systems

NASA Technical Reports Server (NTRS)

Karr, Laurel J.; Van Alstine, James M.; Snyder, Robert S.; Shafer, Steven G.; Harris, J. Milton

1988-01-01

Previous work has shown that polyethylene glycol (PEG)-bound antibodies can be used as affinity ligands in PEG-dextran two-phase systems to provide selective partitioning of cells to the PEG-rich phase. In the present work it is shown that immunoaffinity partitioning can be simplified by use of PEG-modified Protein A which complexes with unmodified antibody and cells and shifts their partitioning into the PEG-rich phase, thus eliminating the need to prepare a PEG-modified antibody for each cell type. In addition, the paper provides a more rigorous test of the original technique with PEG-bound antibodies by showing that it is effective at shifting the partitioning of either cell type of a mixture of two cell populations.

Pregnant Employee Protection Program in a Large Chemical Company.

PubMed

Frey, Gunild; Schuster, Michael; Oberlinner, Christoph; Queier-Wahrendorf, Annette; Lang, Stefan; Yong, Mei

2015-09-01

To assess whether a structured employee protection program for pregnant workers at a chemical company has an impact on pregnancy outcomes. Reported pregnancies (n = 1402) between 2003 and 2010 and their outcomes were documented using questionnaires at the time of pregnancy report, end of pregnancy, and 1 year later. Potential maternal exposures were assessed using job histories, workplace inspections, and questionnaires. Participation was 86% overall and was consistently high across subgroups.Pregnancy losses (10.9%), pregnancy complications, and preterm births (8.1%) were in agreement with rates in the general population and were independent of type of work and maternal exposure category. Pregnancy complication rates in this chemical company are not statistically elevated than that in the general population, as suggested in a previous study. The protection program may play a role in preventing complications that may have occurred.

Needed: Global Collaboration for Comparative Research on Cities and Health

PubMed Central

Gusmano, Michael K.; Rodwin, Victor G.

2016-01-01

Over half of the world’s population lives in cities and United Nations (UN) demographers project an increase of 2.5 billion more urban dwellers by 2050. Yet there is too little systematic comparative research on the practice of urban health policy and management (HPAM), particularly in the megacities of middle-income and developing nations. We make a case for creating a global database on cities, population health and healthcare systems. The expenses involved in data collection would be difficult to justify without some review of previous work, some agreement on indicators worth measuring, conceptual and methodological considerations to guide the construction of the global database, and a set of research questions and hypotheses to test. We, therefore, address these issues in a manner that we hope will stimulate further discussion and collaboration. PMID:27694667

Fertility, Human Capital, and Economic Growth over the Demographic Transition

PubMed Central

Mason, Andrew

2009-01-01

Do low fertility and population aging lead to economic decline if couples have fewer children, but invest more in each child? By addressing this question, this article extends previous work in which the authors show that population aging leads to an increased demand for wealth that can, under some conditions, lead to increased capital per worker and higher per capita consumption. This article is based on an overlapping generations (OLG) model which highlights the quantity–quality tradeoff and the links between human capital investment and economic growth. It incorporates new national level estimates of human capital investment produced by the National Transfer Accounts project. Simulation analysis is employed to show that, even in the absence of the capital dilution effect, low fertility leads to higher per capita consumption through human capital accumulation, given plausible model parameters. PMID:20495605

Needed: Global Collaboration for Comparative Research on Cities and Health.

PubMed

Gusmano, Michael K; Rodwin, Victor G

2016-04-16

Over half of the world's population lives in cities and United Nations (UN) demographers project an increase of 2.5 billion more urban dwellers by 2050. Yet there is too little systematic comparative research on the practice of urban health policy and management (HPAM), particularly in the megacities of middle-income and developing nations. We make a case for creating a global database on cities, population health and healthcare systems. The expenses involved in data collection would be difficult to justify without some review of previous work, some agreement on indicators worth measuring, conceptual and methodological considerations to guide the construction of the global database, and a set of research questions and hypotheses to test. We, therefore, address these issues in a manner that we hope will stimulate further discussion and collaboration. © 2016 by Kerman University of Medical Sciences.

Socio-demographic and work-related risk factors for medium- and long-term sickness absence among Italian workers.

PubMed

d'Errico, Angelo; Costa, Giuseppe

2012-10-01

Few studies investigated determinants of sickness absence in representative samples of the general population, none of which in Italy. Aim of this study was to assess influence and relative importance of socio-demographic and work-related characteristics on medium- and long-term sickness absence in a random sample of Italian workers. Approximately 60,000 workers participating in a national survey in 2007 were interviewed regarding sickness absence during the whole previous week, and on socio-demographics, employment characteristics and exposure to a set of physical and psychosocial hazards in the workplace. The association between sickness absence and potential determinants was estimated by multivariable logistic regression models stratified by gender. From the final multivariate models, in both genders sickness absence was statistically significantly associated with tenure employment, working in larger firms, exposure to risk of injury and to bullying or discrimination and, among employees, with shift work. In males, sickness absence was also associated with lower education, employment in the public administration and with exposure to noise or vibration, whereas among women also with manual work and ergonomic factors. In both genders, the attributable fraction for employment-related characteristics was higher than that for socio-demographic ones. The association with tenure or salaried jobs, and with employment in larger firms or in the public sector suggests that, besides illness, job security is the most important determinant of sickness absence, consistently with the results of previous studies. However, our results indicate that a reduction in exposure to workplace hazards may contribute to reduce absenteeism.

Acoustic neuroma: potential risk factors and audiometric surveillance in the aluminium industry

PubMed Central

Taiwo, Oyebode; Galusha, Deron; Tessier-Sherman, Baylah; Kirsche, Sharon; Cantley, Linda; Slade, Martin D; Cullen, Mark R; Donoghue, A Michael

2014-01-01

Objectives To look for an association between acoustic neuroma (AN) and participation in a hearing conservation programme (HCP) and also for an association between AN and possible occupational risk factors in the aluminium industry. Methods We conducted a case–control analysis of a population of US aluminium production workers in 8 smelters and 43 other plants. Using insurance claims data, 97 cases of AN were identified between 1996 and 2009. Each was matched with four controls. Covariates included participation in a HCP, working in an aluminium smelter, working in an electrical job and hearing loss. Results In the bivariate analyses, covariates associated with AN were participation in the HCP (OR=1.72; 95% CI 1.09 to 2.69) and smelter work (OR=1.88; 95% CI 1.06 to 3.36). Electrical work was not significant (OR=1.60; 95% CI 0.65 to 3.94). Owing to high participation in the HCP in smelters, multivariate subanalyses were required. In the multivariate analyses, participation in the HCP was the only statistically significant risk factor for AN. In the multivariate analysis restricted to employees not working in a smelter, the OR was 1.81 (95% CI 1.04 to 3.17). Hearing loss, an indirect measure of in-ear noise dose, was not predictive of AN. Conclusions Our results suggest the incidental detection of previously undiagnosed tumours in workers who participated in the company-sponsored HCP. The increased medical surveillance among this population of workers most likely introduced detection bias, leading to the identification of AN cases that would have otherwise remained undetected. PMID:25015928

Supramodal parametric working memory processing in humans.

PubMed

Spitzer, Bernhard; Blankenburg, Felix

2012-03-07

Previous studies of delayed-match-to-sample (DMTS) frequency discrimination in animals and humans have succeeded in delineating the neural signature of frequency processing in somatosensory working memory (WM). During retention of vibrotactile frequencies, stimulus-dependent single-cell and population activity in prefrontal cortex was found to reflect the task-relevant memory content, whereas increases in occipital alpha activity signaled the disengagement of areas not relevant for the tactile task. Here, we recorded EEG from human participants to determine the extent to which these mechanisms can be generalized to frequency retention in the visual and auditory domains. Subjects performed analogous variants of a DMTS frequency discrimination task, with the frequency information presented either visually, auditorily, or by vibrotactile stimulation. Examining oscillatory EEG activity during frequency retention, we found characteristic topographical distributions of alpha power over visual, auditory, and somatosensory cortices, indicating systematic patterns of inhibition and engagement of early sensory areas, depending on stimulus modality. The task-relevant frequency information, in contrast, was found to be represented in right prefrontal cortex, independent of presentation mode. In each of the three modality conditions, parametric modulations of prefrontal upper beta activity (20-30 Hz) emerged, in a very similar manner as recently found in vibrotactile tasks. Together, the findings corroborate a view of parametric WM as supramodal internal scaling of abstract quantity information and suggest strong relevance of previous evidence from vibrotactile work for a more general framework of quantity processing in human working memory.

The impact of adjusted work conditions and disease-modifying drugs on work ability in multiple sclerosis.

PubMed

Wickström, Anne; Fagerström, Maria; Wickström, Lucas; Granåsen, Gabriel; Dahle, Charlotte; Vrethem, Magnus; Sundström, Peter

2017-07-01

Multiple sclerosis (MS) is a neurological disorder that causes significantly reduced ability to work, and the Expanded Disability Status Scale (EDSS) is one of the main predictors for reduced work ability. To investigate how work requirements, flexible work conditions and disease-modifying drugs (DMDs) influence the work ability in relation to different EDSS grades in two MS populations. Work ability was studied in two MS populations: one in the southern and one in the northern part of Sweden, both demographically similar. In the latter population, more active work-promoting interventions have been practised and second-generation DMDs have been widely used from the onset of disease for several years. The proportion of MS patients who participated in the workforce or studied was significantly higher in the northern compared with the southern population ( p < 0.001). The employees in the northern population had significantly lower requirements, greater adapted work conditions and were able to work more hours per week. Higher EDSS was associated with lower reduction in number of worked hours per week in the northern population ( p = 0.042). Our data indicated that treatment strategy and adjusted work conditions have impact on work ability in MS.

Psychosocial and organizational risk factors for doctor-certified sick leave: a prospective study of female health and social workers in Norway.

PubMed

Aagestad, Cecilie; Tyssen, Reidar; Johannessen, Håkon A; Gravseth, Hans Magne; Tynes, Tore; Sterud, Tom

2014-09-29

Doctor-certified sick leave differs substantially across sectors, and among health and social workers, in particular, there is an increased risk. Previous studies have shown that work environmental factors contribute to sick leave. Hence, the identification of specific organizational and psychosocial risk factors for long- term sick leave, taking into account potential confounding related to mechanical risk factors such as lifting and awkward body postures, will be of importance in the work of prevention. A randomly drawn population sample of Norwegian residents was interviewed about working conditions in 2009 (n = 12,255; response rate 60.9%). Female health and social care workers (n = 925) were followed in a national registry for subsequent sickness absence during 2010. The outcome of interest was doctor-certified sick leave of 21 days or more (long-term sick leave). Eleven work-related psychosocial and organizational factors were evaluated. In total, 186 persons (20.1%) were classified with subsequent long-term sick leave. After thoroughly adjusting for competing explanatory variables, the most consistent predictors for long-term sick leave were violence and threats of violence (OR = 1.67; 95% CI 1.14-2.45). The estimated population attributable risk for violence and threats of violence was 13%. The present study among female health and social care workers revealed a substantial relationship between self-reported violence and threats of violence and subsequent long- term sick leave.

Snakebite and Its Socio-Economic Impact on the Rural Population of Tamil Nadu, India

PubMed Central

Vaiyapuri, Sakthivel; Vaiyapuri, Rajendran; Ashokan, Rajesh; Ramasamy, Karthikeyan; Nattamaisundar, Kameshwaran; Jeyaraj, Anburaj; Chandran, Viswanathan; Gajjeraman, Prabu; Baksh, M. Fazil; Gibbins, Jonathan M.; Hutchinson, E. Gail

2013-01-01

Background Snakebite represents a significant health issue worldwide, affecting several million people each year with as many as 95,000 deaths. India is considered to be the country most affected, but much remains unknown about snakebite incidence in this country, its socio-economic impact and how snakebite management could be improved. Methods/Principal Findings We conducted a study within rural villages in Tamil Nadu, India, which combines a household survey (28,494 people) of snakebite incidence with a more detailed survey of victims in order to understand the health and socio-economic effects of the bite, the treatments obtained and their views about future improvements. Our survey suggests that snakebite incidence is higher than previously reported. 3.9% of those surveyed had suffered from snakebite and the number of deaths corresponds to 0.45% of the population. The socio-economic impact of this is very considerable in terms of the treatment costs and the long-term effects on the health and ability of survivors to work. To reduce this, the victims recommended improvements to the accessibility and affordability of antivenom treatment. Conclusions Snakebite has a considerable and disproportionate impact on rural populations, particularly in South Asia. This study provides an incentive for researchers and the public to work together to reduce the incidence and improve the outcomes for snake bite victims and their families. PMID:24278244

The relationship between out-of-home care and the quality of infant-mother attachment in an economically disadvantaged population.

PubMed

Vaughn, B E; Gove, F L; Egeland, B

1980-12-01

The effects of routine daily separations occasioned by out-of-home care on the formation and maintenance of infant-mother attachment relationships were examined in a population of economically disadvantaged mothers. 3 groups were constituted on the basis of the time in the infant's life when out-of-home care began: (1) before 12 months; (2) between 12 and 18 months; (3) home-care controls. The infant-mother pairs were observed in the Ainsworth strange situation at both 12 and 18 months, and were classified as secure, anxious-avoidant, or anxious-resistant. Because previous research has implicated the psychological accessibility of the mother to the infant in the development of anxious-avoidant attachments during the first year of life, the hypothesis that physical inaccessibility due to out-of-home care would also be associated with anxious-avoidant attachments was tested. The data support this hypothesis. At 12 months 47% of the infants whose mothers had returned to work/school were classified in the anxious-avoidant group, while the other 2 groups did not differ significantly in the proportions of infants assigned to the 3 attachment classifications. At 18 months, differences among the 3 work status groups also showed a large portion of anxious-avoidant infants (41%) in this early working group. However, infants whose out-of-home care began after 12 months did not show an increase in the proportion of anxious attachments. Additional analyses of variables related to mother's return to work indicated that single mothers were more likely to return to work/school, that mothers who worked reported higher levels of life stress than mothers who stayed home with the infants, and that, by 18 months, both anxious-avoidant and anxious-resistant attachments were also associated with non-intact families.

Sports- and Work-Related Outcomes After Shoulder Hemiarthroplasty.

PubMed

Garcia, Grant H; Mahony, Gregory T; Fabricant, Peter D; Wu, Hao-Hua; Dines, David M; Warren, Russell F; Craig, Edward V; Gulotta, Lawrence V

2016-02-01

With an active aging population, more patients expect to return to previous activities and work after surgery. To determine the rate and timing to return of sports and employment after shoulder hemiarthroplasty. Case series; Level of evidence, 4. This was a retrospective review of consecutive patients who underwent shoulder hemiarthroplasty from 2007 to 2013. Follow-up consisted of a patient-reported questionnaire regarding physical fitness, sporting activities, and work status. From 105 patients screened, 79 were available for follow-up. The average follow-up time was 63.1 months, and the average age at follow-up was 69 years. Scores on the visual analog scale for pain improved from 6.2 to 2.1 (P < .001) postoperatively, and those on the American Shoulder and Elbow Surgeons (ASES) shoulder assessment improved from 34.6 to 71.3 (P < .001). Patients older than 65 years had significantly lower absolute postoperative ASES scores (P = .041) but experienced similar improvement from their preoperative baseline (P = .158) compared with patients younger than 65 years. There were 58 patients who played sports preoperatively, and 67.2% of these restarted at least 1 of their previous sports postoperatively. The average time to return to full sports was 6.5 months for those who returned. Direct rates of return were as follows: fitness sports (69%), swimming (65%), running (64%), cycling (63%), and doubles tennis (57%). Younger age was associated with highest demand level achieved (P = .023). Forty-nine patients worked preoperatively, with 69.4% returning to previous employment after surgery; the average time to return to work was 1.4 months. In comparative analysis, patients who did not return to work had a higher mean body mass index (32 ± 7 vs 27 ± 5 kg/m(2); P < .008). In this hemiarthroplasty cohort, there was a 67.2% rate of return to 1 or more sports at an average of 6.5 months postoperatively. Patients older than 65 years experienced similar improvements in ASES scores compared with patients younger than 65 years, although absolute scores were lower on average. Those who returned to higher demand sports were younger on average. Of patients working preoperatively, 69.4% returned to their previous employment at an average of 1.4 months. Patients who did not return to employment had significantly higher body mass index on average. These findings will help surgeons manage expectations of shoulder hemiarthroplasty candidates preoperatively. © 2015 The Author(s).

Methodological choices affect cancer incidence rates: a cohort study.

PubMed

Brooke, Hannah L; Talbäck, Mats; Feychting, Maria; Ljung, Rickard

2017-01-19

Incidence rates are fundamental to epidemiology, but their magnitude and interpretation depend on methodological choices. We aimed to examine the extent to which the definition of the study population affects cancer incidence rates. All primary cancer diagnoses in Sweden between 1958 and 2010 were identified from the national Cancer Register. Age-standardized and age-specific incidence rates of 29 cancer subtypes between 2000 and 2010 were calculated using four definitions of the study population: persons resident in Sweden 1) based on general population statistics; 2) with no previous subtype-specific cancer diagnosis; 3) with no previous cancer diagnosis except non-melanoma skin cancer; and 4) with no previous cancer diagnosis of any type. We calculated absolute and relative differences between methods. Age-standardized incidence rates calculated using general population statistics ranged from 6% lower (prostate cancer, incidence rate difference: -13.5/100,000 person-years) to 8% higher (breast cancer in women, incidence rate difference: 10.5/100,000 person-years) than incidence rates based on individuals with no previous subtype-specific cancer diagnosis. Age-standardized incidence rates in persons with no previous cancer of any type were up to 10% lower (bladder cancer in women) than rates in those with no previous subtype-specific cancer diagnosis; however, absolute differences were <5/100,000 person-years for all cancer subtypes. For some cancer subtypes incidence rates vary depending on the definition of the study population. For these subtypes, standardized incidence ratios calculated using general population statistics could be misleading. Moreover, etiological arguments should be used to inform methodological choices during study design.

Genetic, Ecological and Morphological Divergence between Populations of the Endangered Mexican Sheartail Hummingbird (Doricha eliza)

PubMed Central

Licona-Vera, Yuyini; Ornelas, Juan Francisco

2014-01-01

The Mexican Sheartail (Doricha eliza), an endangered hummingbird, is endemic to Mexico where two populations have a disjunct distribution. One population is distributed along the northern tip of the Yucatan Peninsula whereas the other is mostly restricted to central Veracruz. Despite their disjunct distribution, previous work has failed to detect morphological or behavioral differences between these populations. Here we use variation in morphology, mtDNA and nuDNA sequences to determine the degree of morphological and molecular divergence between populations, their divergence time, and historical demography. We use species distribution modeling and niche divergence tests to infer the relative roles of vicariance and dispersal in driving divergence in the genus. Our Bayesian and maximum likelihood phylogenetic analyses revealed that Doricha eliza populations form a monophyletic clade and support their sister relationship with D. enicura. We found marked genetic differentiation, with reciprocal monophyly of haplotypes and highly restricted gene flow, supporting a history of isolation over the last 120,000 years. Genetic divergence between populations is consistent with the lack of overlap in environmental space and slight morphological differences between males. Our findings indicate that the divergence of the Veracruz and Yucatan populations is best explained by a combination of a short period of isolation exacerbated by subsequent divergence in climate conditions, and that rather than vicariance, the two isolated ranges of D. eliza are the product of recent colonization and divergence in isolation. PMID:24992589

The peopling of Greenland: further insights from the analysis of genetic diversity using autosomal and X-chromosomal markers

PubMed Central

Pereira, Vania; Tomas, Carmen; Sanchez, Juan J; Syndercombe-Court, Denise; Amorim, António; Gusmão, Leonor; Prata, Maria João; Morling, Niels

2015-01-01

The peopling of Greenland has a complex history shaped by population migrations, isolation and genetic drift. The Greenlanders present a genetic heritage with components of European and Inuit groups; previous studies using uniparentally inherited markers in Greenlanders have reported evidence of a sex-biased, admixed genetic background. This work further explores the genetics of the Greenlanders by analysing autosomal and X-chromosomal data to obtain deeper insights into the factors that shaped the genetic diversity in Greenlanders. Fourteen Greenlandic subsamples from multiple geographical settlements were compared to assess the level of genetic substructure in the Greenlandic population. The results showed low levels of genetic diversity in all sets of the genetic markers studied, together with an increased number of X-chromosomal loci in linkage disequilibrium in relation to the Danish population. In the broader context of worldwide populations, Greenlanders are remarkably different from most populations, but they are genetically closer to some Inuit groups from Alaska. Admixture analyses identified an Inuit component in the Greenlandic population of approximately 80%. The sub-populations of Ammassalik and Nanortalik are the least diverse, presenting the lowest levels of European admixture. Isolation-by-distance analyses showed that only 16% of the genetic substructure of Greenlanders is most likely to be explained by geographic barriers. We suggest that genetic drift and a differentiated settlement history around the island explain most of the genetic substructure of the population in Greenland. PMID:24801759

The peopling of Greenland: further insights from the analysis of genetic diversity using autosomal and X-chromosomal markers.

PubMed

Pereira, Vania; Tomas, Carmen; Sanchez, Juan J; Syndercombe-Court, Denise; Amorim, António; Gusmão, Leonor; Prata, Maria João; Morling, Niels

2015-02-01

The peopling of Greenland has a complex history shaped by population migrations, isolation and genetic drift. The Greenlanders present a genetic heritage with components of European and Inuit groups; previous studies using uniparentally inherited markers in Greenlanders have reported evidence of a sex-biased, admixed genetic background. This work further explores the genetics of the Greenlanders by analysing autosomal and X-chromosomal data to obtain deeper insights into the factors that shaped the genetic diversity in Greenlanders. Fourteen Greenlandic subsamples from multiple geographical settlements were compared to assess the level of genetic substructure in the Greenlandic population. The results showed low levels of genetic diversity in all sets of the genetic markers studied, together with an increased number of X-chromosomal loci in linkage disequilibrium in relation to the Danish population. In the broader context of worldwide populations, Greenlanders are remarkably different from most populations, but they are genetically closer to some Inuit groups from Alaska. Admixture analyses identified an Inuit component in the Greenlandic population of approximately 80%. The sub-populations of Ammassalik and Nanortalik are the least diverse, presenting the lowest levels of European admixture. Isolation-by-distance analyses showed that only 16% of the genetic substructure of Greenlanders is most likely to be explained by geographic barriers. We suggest that genetic drift and a differentiated settlement history around the island explain most of the genetic substructure of the population in Greenland.

Fluorine Variations in the Globular Cluster NGC 6656 (M22): Implications for Internal Enrichment Timescales

NASA Astrophysics Data System (ADS)

D'Orazi, Valentina; Lucatello, Sara; Lugaro, Maria; Gratton, Raffaele G.; Angelou, George; Bragaglia, Angela; Carretta, Eugenio; Alves-Brito, Alan; Ivans, Inese I.; Masseron, Thomas; Mucciarelli, Alessio

2013-01-01

Observed chemical (anti)correlations in proton-capture elements among globular cluster stars are presently recognized as the signature of self-enrichment from now extinct, previous generations of stars. This defines the multiple population scenario. Since fluorine is also affected by proton captures, determining its abundance in globular clusters provides new and complementary clues regarding the nature of these previous generations and supplies strong observational constraints to the chemical enrichment timescales. In this paper, we present our results on near-infrared CRIRES spectroscopic observations of six cool giant stars in NGC 6656 (M22): the main objective is to derive the F content and its internal variation in this peculiar cluster, which exhibits significant changes in both light- and heavy-element abundances. Across our sample, we detected F variations beyond the measurement uncertainties and found that the F abundances are positively correlated with O and anticorrelated with Na, as expected according to the multiple population framework. Furthermore, our observations reveal an increase in the F content between the two different sub-groups, s-process rich and s-process poor, hosted within M22. The comparison with theoretical models suggests that asymptotic giant stars with masses between 4 and 5 M ⊙ are responsible for the observed chemical pattern, confirming evidence from previous works: the difference in age between the two sub-components in M22 must be not larger than a few hundred Myr. Based on observations taken with ESO telescopes under program 087.0319(A).

Genomics and introgression: discovery and mapping of thousands of species-diagnostic SNPs using RAD sequencing

USGS Publications Warehouse

Hand, Brian K.; Hether, Tyler D; Kovach, Ryan P.; Muhlfeld, Clint C.; Amish, Stephen J.; Boyer, Matthew C.; O’Rourke, Sean M.; Miller, Michael R.; Lowe, Winsor H.; Hohenlohe, Paul A.; Luikart, Gordon

2015-01-01

Invasive hybridization and introgression pose a serious threat to the persistence of many native species. Understanding the effects of hybridization on native populations (e.g., fitness consequences) requires numerous species-diagnostic loci distributed genome-wide. Here we used RAD sequencing to discover thousands of single-nucleotide polymorphisms (SNPs) that are diagnostic between rainbow trout (RBT, Oncorhynchus mykiss), the world’s most widely introduced fish, and native westslope cutthroat trout (WCT, O. clarkii lewisi) in the northern Rocky Mountains, USA. We advanced previous work that identified 4,914 species-diagnostic loci by using longer sequence reads (100 bp vs. 60 bp) and a larger set of individuals (n = 84). We sequenced RAD libraries for individuals from diverse sampling sources, including native populations of WCT and hatchery broodstocks of WCT and RBT. We also took advantage of a newly released reference genome assembly for RBT to align our RAD loci. In total, we discovered 16,788 putatively diagnostic SNPs, 10,267 of which we mapped to anchored chromosome locations on the RBT genome. A small portion of previously discovered putative diagnostic loci (325 of 4,914) were no longer diagnostic (i.e., fixed between species) based on our wider survey of non-hybridized RBT and WCT individuals. Our study suggests that RAD loci mapped to a draft genome assembly could provide the marker density required to identify genes and chromosomal regions influencing selection in admixed populations of conservation concern and evolutionary interest.

The measurement and analysis of leaf spectral reflectance of two stands of loblolly pine populations

NASA Technical Reports Server (NTRS)

Paul, Anthony D.

1993-01-01

My research was conducted under the mentorship of Dr. Jeff Luvall. I worked at Marshall from June 1 through August 6, 1993. My proposal is titled 'The Measurement and Analysis of Leaf Spectral Reflectance of Two Stands of Loblolly Pine Populations.' The populations for this study were chosen from a larger population of 31 families managed by the International Forest Seed Company, Odenville, Alabama. The technology for mobile ground base spectral detecting is new and therefore the majority of time, June 2 through July 9, was spent on learning the techniques of the Spectrometer 2 spectroradiometer used in the gathering of spectra information. The activities included in the learning process were as follows: calibration of the equipment, programming the associated computer for data management, operation of the spectral devices, and input and output of data. From July 12 through August 3 the time was spent on learning the 'STATGRAP' computer software. This software will be used in the analysis of the data retrieved by the Spectrometer 2 spectroradiometer. Dr. Greg Carter, at Stennis, a colleague of Dr. Luvall, has been conducting similar work with different instruments and procedures and has agreed to host us for a training session on data gathering and analysis. This visit, which has previously planned for July 9, 1993, but had to be postponed because of schedule conflicts, is now confirmed for August 18-22, 1993. This trip to Stennis will provide the knowledge for conducting the field operations in my study, i.e., gathering of data and file conversions.

Distinct alterations in value-based decision-making and cognitive control in suicide attempters: toward a dual neurocognitive model.

PubMed

Richard-Devantoy, Stéphane; Olié, Emilie; Guillaume, Sébastien; Bechara, Antoine; Courtet, Philippe; Jollant, Fabrice

2013-12-01

The literature suggests that many suicide attempters show impairment in both decision-making and cognitive control. However, it is not clear if these deficits are linked to each other, and if they may be related to more basic alterations in attention. This is a relevant question in the perspective of future interventions targeting cognitive deficits to prevent suicidal acts. Two different populations of patients with histories of suicide attempts were assessed (N=142 and 119). The Iowa Gambling Task (IGT) was used to measure decision-making in both populations. We used a D2 cancellation task and a verbal working memory task in population 1; the Stroop test, the N-Back task, the Trail Making Test, and the Hayling Sentence Completion test in population 2. Regarding decision-making, we only found a small negative correlation between the Hayling test error score (r=-0.24; p=0.01), and the net score from the second half of the IGT. In contrast, working memory, cognitive flexibility and cognitive inhibition measures were largely inter-correlated. Most patients were medicated. Only patients with mood disorders. These results add to previous findings suggesting that the neurocognitive vulnerability to suicidal behavior may rely on impairments in two distinct anatomical systems, one processing value-based decision-making (associated with ventral prefrontal cortex, among others) and one underlying cognitive control (associated with more dorsal prefrontal regions). This distinction may result in tailored-made cognitive interventions. Copyright © 2013 Elsevier B.V. All rights reserved.

[Prevalence of dermatomycoses in professional football players : A study based on data of German Bundesliga fitness check-ups (2013-2015) compared to data of the general population].

PubMed

Buder, V; Augustin, M; Schäfer, I; Welsch, G; Catala-Lehnen, P; Herberger, K

2018-05-01

The prevention, early diagnosis and treatment of onychomycosis is of great importance for professional athletes to avoid physical limitations by complications. So far, there is only little data on the prevalence of dermatomycosis in professional athletes. The aim of the study was to detect the prevalence of dermatomycosis in professional football players compared to the general population. The prospective, non-interventional, controlled study on the prevalence of dermatomycosis in professional football players was carried out on football players of a German Bundesliga team compared with a previously studied, equivalently aged German working population. A questionnaire survey, a dermatological check-up and a microbiological detection of pathogens in cases of suspicion were performed. Data of 84 football players (n = 45 in 2013; n = 39 in 2015) were compared to data of n = 8186 male employees between 17 and 35 years of age. In the group of athletes, there were findings of 60.7% onychomycosis, 36.9% of tinea pedis and 17.8% of pityriasis versicolor. In the group of the age-equivalent general German working population the findings were: onychomycosis 3.3%, tinea pedis 3.2%, pityriasis versicolor 1.4%. Our study shows a clearly higher risk for fungal diseases of the skin especially on the feet of professional football players. The results show a necessity for elucidation within prevention and the establishment of an appropriate therapy of dermatomycosis for professional football players.

Poliomyelitis: long-time consequences for social life.

PubMed

Farbu, E; Gilhus, N E

1997-12-01

In a study of 102 consecutive patients hospitalized for previous poliomyelitis, we found that 70 patients had continued education after elementary school and 18 were academics. This is a higher proportion than in the general Norwegian population. All 14 patients with paraparesis had continued education after elementary school, while as many as 12 of 18 patients with a university degree had widespread pareses in the acute phase. Of the patients 46 worked or had worked full-time up to 60 years of age. Only 29 patients were receiving a disabled pension. Another 9 patients had neither been employed nor received any pension, all housewives. Nine of 14 patients with paraparesis were working full-time, only 2 received disabled pension. Among the 35 patients with persisting widespread pareses, 11 were still in full-time work and 7 were working part-time. The employment rate among the patients in this study was nearly identical to the age-correlated general employment rate in Norway. Our conclusion is that polio patients are doing well in society; they have taken education, are working, and are generally self-supported. The degree of pareses does not seem to have been the most determining factor for their educational and professional activity.

The emotional costs of caring incurred by men and women in the British labour market.

PubMed

Barron, David Nicholas; West, Elizabeth

2007-11-01

This study investigates whether men and women in caring occupations experience more negative job-related feelings at the end of the day compared to the rest of the working population. The data are from Wave Nine of the British Household Panel Survey (1999) where respondents were asked whether, at the end of the working day, they tended to keep worrying or have trouble unwinding, and the extent to which work left them feeling exhausted or "used up." Their responses to these questions were used to develop ordinal dependent variables. Control variables in the models include: number of children, age, hours worked per week, managerial responsibilities and job satisfaction, all of which have been shown in previous research to be significantly related to "job burnout." The results are that those in caring occupations are more likely to feel worried, tense, drained and exhausted at the end of the working day. Women in particular appear to pay a high emotional cost for working in caring occupations. Men do not emerge unscathed, but report significantly lower levels of worry and exhaustion at the end of the day than do women.

Habitat Association and Seasonality in a Mosaic and Bimodal Hybrid Zone between Chorthippus brunneus and C. jacobsi (Orthoptera: Acrididae)

PubMed Central

Tatsuta, Haruki; Butlin, Roger K.

2012-01-01

Understanding why some hybrid zones are bimodal and others unimodal can aid in identifying barriers to gene exchange following secondary contact. The hybrid zone between the grasshoppers Chorthippus brunneus and C. jacobsi contains a mix of allopatric parental populations and inter-mingled bimodal and unimodal sympatric populations, and provides an ideal system to examine the roles of local selection and gene flow between populations in maintaining bimodality. However, it is first necessary to confirm, over a larger spatial scale, previously identified associations between population composition and season and habitat. Here we use cline-fitting of one morphological and one song trait along two valley transects, and intervening mountains, to confirm previously identified habitat associations (mountain versus valley) and seasonal changes in population composition. As expected from previous findings of studies on a smaller spatial scale, C. jacobsi dominated mountain habitats and mixed populations dominated valleys, and C. brunneus became more prevalent in August. Controlling for habitat and incorporating into the analysis seasonal changes in cline parameters and the standard errors of parental trait values revealed wider clines than previous studies (best estimates of 6.4 to 24.5 km in our study versus 2.8 to 4.7 km in previous studies) and increased percentage of trait variance explained (52.7% and 61.5% for transects 1 and 2 respectively, versus 17.6%). Revealing such strong and consistent patterns within a complex hybrid zone will allow more focused examination of the causes of variation in bimodality in mixed populations, in particular the roles of local selection versus habitat heterogeneity and gene flow between differentiated populations. PMID:22675485

Satisfaction with a 2-day communication skills course culturally tailored for medical specialists in Qatar.

PubMed

Bylund, Carma L; Alyafei, Khalid; Afana, Abdelhamid; Al-Romaihi, Sheyma; Yassin, Mohammed; Elnashar, Maha; Al-Arab, Banan; Al-Khal, Abdullatif

2017-01-01

Health-care communication skills training may be particularly needed in the Arabian Gulf countries because of the variety of cultures within the physician and patient populations. This study describes the implementation and results of a communication skills training program for physicians in Qatar that assessed previous training, and effect of previous training on participants' course evaluations. We conducted a 2-day communication skills training course covering seven culturally adapted modules. Educational strategies included large and small group work with the standardized patient, demonstration videos, and lectures. At the end, participants completed a course evaluation survey. Data analysis performed with SPSS; frequencies and percentages were calculated, and Chi-square test applied to evaluate statistical significance. A total of 410 physicians in Qatar have participated in the course over a period of 2 years. Evaluation ratings of the course were high. Participants rated the module on Breaking Bad News as the most useful, and the small group role-play as the most helpful course component. One-third of participants had previously participated in experiential communication skills training. There was no association between previous experience and evaluation of the course. Physicians in Qatar positively evaluated a 2-day communication skills course, though the majority of participants did not have any previous exposure to experiential communication skills training.

Some features of Australian exhibitionists compared with pedophiles.

PubMed

Myers, R G; Berah, E F

1983-12-01

In an attempt to extend the findings of previous research and to investigate the hypothesis of a link between exhibitionism and pedophilia, samples of Australian offenders undergoing presentence psychiatric assessment were compared on a number of variables. The data suggested that the exhibitionists and pedophiles in the sample represented different populations: the exhibitionists were younger, tended to come from more stable and harmonious families, and had superior school and work records. The common assumption of disinhibition as a feature of exhibitionism was questioned on the basis of the finding that almost no exhibitionists were intoxicated at the time of their offense.

National Convention on Family Life Education.

PubMed

1973-12-01

This secretarial report gives brief comments on some discussion of topics at the National Convention on Family Life Education. Discussion included: 1) legalized prostitution as a means to reduce venereal disease; 2) family life education promotion by government and civic groups; 3) more authority for the Population Council; 4) more liberal abortion legislation than previously; 5) statutory notification of veneral disease by medical practitioners; 6) compensatory measures for working women with young children, and 7) the need for modernization of legislation pertaining to child health, adoption, paternity, the Persons Act, infant life preservation, drugs, age of consent, and the age of minority.

Rivastigmine in moderately severe-to-severe Alzheimer’s disease: Severe Impairment Battery factor analysis

PubMed Central

2013-01-01

Introduction The Severe Impairment Battery (SIB) is validated for assessing cognition in patients with severe dementia. The current analysis aimed to further investigate the cognitive efficacy of rivastigmine capsules, as assessed by SIB factor scores, in patients with moderately severe-to-severe Alzheimer’s disease (AD). Methods This was a retrospective analysis of a 26-week, multicenter, randomized, double-blind, placebo-controlled study of oral rivastigmine conducted in Spain. Previously reported outcome measures included the full SIB. Current analyses examined calculated scores and effect sizes for the change from baseline at Week 26 on: newly defined SIB subscales (derived by a factor analysis of the 40 SIB items, using the PROC FACTOR function (SAS)); previously defined memory, language and praxis subscales (derived by previous analysis of the nine SIB domains); and the individual SIB items. Treatment differences were assessed. Results SIB data were provided by 104 rivastigmine-treated patients and 106 patients receiving placebo (Intent-To-Treat Last Observation Carried Forward population). Significantly less decline was observed on the previously defined memory and language subscales, and the newly defined working memory/memory subscale in rivastigmine-treated patients (all P < 0.05 versus placebo). Calculation of effect sizes demonstrated numerically greater efficacy of rivastigmine versus placebo on each of the subscales, and a broad range of SIB items; greatest effect sizes were observed on SIB items assessing the current month (effect size = 0.30) and digit span series (effect size = 0.33). Conclusions These data suggest the observed efficacy of rivastigmine in moderately severe-to-severe AD is likely a cumulative effect across a range of tasks. Rivastigmine demonstrates broad cognitive efficacy in this patient population. PMID:24351447

Point process models for localization and interdependence of punctate cellular structures.

PubMed

Li, Ying; Majarian, Timothy D; Naik, Armaghan W; Johnson, Gregory R; Murphy, Robert F

2016-07-01

Accurate representations of cellular organization for multiple eukaryotic cell types are required for creating predictive models of dynamic cellular function. To this end, we have previously developed the CellOrganizer platform, an open source system for generative modeling of cellular components from microscopy images. CellOrganizer models capture the inherent heterogeneity in the spatial distribution, size, and quantity of different components among a cell population. Furthermore, CellOrganizer can generate quantitatively realistic synthetic images that reflect the underlying cell population. A current focus of the project is to model the complex, interdependent nature of organelle localization. We built upon previous work on developing multiple non-parametric models of organelles or structures that show punctate patterns. The previous models described the relationships between the subcellular localization of puncta and the positions of cell and nuclear membranes and microtubules. We extend these models to consider the relationship to the endoplasmic reticulum (ER), and to consider the relationship between the positions of different puncta of the same type. Our results do not suggest that the punctate patterns we examined are dependent on ER position or inter- and intra-class proximity. With these results, we built classifiers to update previous assignments of proteins to one of 11 patterns in three distinct cell lines. Our generative models demonstrate the ability to construct statistically accurate representations of puncta localization from simple cellular markers in distinct cell types, capturing the complex phenomena of cellular structure interaction with little human input. This protocol represents a novel approach to vesicular protein annotation, a field that is often neglected in high-throughput microscopy. These results suggest that spatial point process models provide useful insight with respect to the spatial dependence between cellular structures. © 2016 International Society for Advancement of Cytometry. © 2016 International Society for Advancement of Cytometry.

Emulating Native Periosteum Cell Population and Subsequent Paracrine Factor Production To Promote Tissue Engineered Periosteum-Mediated Allograft Healing

PubMed Central

Hoffman, Michael D.

2015-01-01

Emulating autograft healing within the context of decellularized bone allografts has immediate clinical applications in the treatment of critical-sized bone defects. The periosteum, a thin, osteogenic tissue that surrounds bone, houses a heterogeneous population of stem cells and osteoprogenitors. There is evidence that periosteum-cell derived paracrine factors, specifically vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP2), orchestrate autograft healing through host cell recruitment and subsequent tissue elaboration. In previous work, we demonstrated that the use of poly(ethylene glycol) (PEG) hydrogels as a tissue engineered (T.E.) periosteum to localize mesenchymal stem cells (MSCs) to the surface of decellularized bone enhances allograft healing and integration. Herein, we utilize a mixed population of 50:50 MSCs and osteoprogenitor cells to better mimic native periosteum cell population and paracrine factor production to further promote allograft healing. This mixed cell population was localized to the surface of decellularized allografts within degradable hydrogels and shown to expedite allograft healing. Specifically, bone callus formation and biomechanical graft-host integration are increased as compared to unmodified allografts. These results demonstrate the dual importance of periosteum-mediated paracrine factors orchestrating host cell recruitment as well as new bone formation while developing clinically translatable strategies for allograft healing and integration. PMID:25818449

Repeatability and degree of territorial aggression differs among urban and rural great tits (Parus major).

PubMed

Hardman, Samuel I; Dalesman, Sarah

2018-03-22

Animals in urban habitats face many novel selection pressures such as increased human population densities and human disturbance. This is predicted to favour bolder and more aggressive individuals together with greater flexibility in behaviour. Previous work has focussed primarily on studying these traits in captive birds and has shown increased aggression and reduced consistency between traits (behavioural syndromes) in birds from urban populations. However, personality (consistency within a behavioural trait) has not been well studied in the wild. Here we tested whether urban free-living male great tits show greater territorial aggression than rural counterparts. We also tested predictions that both behavioural syndromes and personality would show lower consistency in urban populations. We found that urban populations were more aggressive than rural populations and urban birds appeared to show lower levels of individual behavioural repeatability (personality) as predicted. However, we found no effect of urbanisation on behavioural syndromes (correlations between multiple behavioural traits). Our results indicate that urban environments may favour individuals which exhibit increased territorial aggression and greater within-trait flexibility which may be essential to success in holding urban territories. Determining how urban environments impact key fitness traits will be important in predicting how animals cope with ongoing urbanisation.

Quorum Sensing in Populations of Spatially Extended Chaotic Oscillators Coupled Indirectly via a Heterogeneous Environment

NASA Astrophysics Data System (ADS)

Li, Bing-Wei; Cao, Xiao-Zhi; Fu, Chenbo

2017-12-01

Many biological and chemical systems could be modeled by a population of oscillators coupled indirectly via a dynamical environment. Essentially, the environment by which the individual element communicates with each other is heterogeneous. Nevertheless, most of previous works considered the homogeneous case only. Here we investigated the dynamical behaviors in a population of spatially distributed chaotic oscillators immersed in a heterogeneous environment. Various dynamical synchronization states (such as oscillation death, phase synchronization, and complete synchronized oscillation) as well as their transitions were explored. In particular, we uncovered a non-traditional quorum sensing transition: increasing the population density leaded to a transition from oscillation death to synchronized oscillation at first, but further increasing the density resulted in degeneration from complete synchronization to phase synchronization or even from phase synchronization to desynchronization. The underlying mechanism of this finding was attributed to the dual roles played by the population density. What's more, by treating the environment as another component of the oscillator, the full system was then effectively equivalent to a locally coupled system. This fact allowed us to utilize the master stability functions approach to predict the occurrence of complete synchronization oscillation, which agreed with that from the direct numerical integration of the system. The potential candidates for the experimental realization of our model were also discussed.

Physician assistants as servant leaders: meeting the needs of the underserved.

PubMed

Huckabee, Michael J; Wheeler, Daniel W

2011-01-01

The purpose of this study was to determine if the level of servant leader characteristics in clinically practicing physician assistants (PAs) in underserved populations differed from PAs serving in other locales. Five subscales of servant leadership: altruistic calling, emotional healing, wisdom, persuasive mapping, and organizational stewardship, were measured in a quantitative study of clinically practicing PAs using a self-rating survey and a similar survey by others rating the PA. Of 777 PAs invited, 321 completed the survey. On a scale of 1 to 5, mean PA self-ratings ranged from 3.52 (persuasive mapping) to 4.05 (wisdom). Other raters' scores paired with the self-rated PA scores were comparable in all subscales except wisdom, which was rated higher by the other raters (4.32 by other raters, 4.01 by PAs, P= .002). There was no significant difference in the measures of servant leadership reported by PAs serving the underserved compared to PAs serving in other populations. Servant leader subscales were higher for PAs compared to previous studies of other health care or community leader populations. The results found that the PA population studied had a prominent level of servant leadership characteristics that did not differ between those working with underserved and nonunderserved populations.

Population continuity vs. discontinuity revisited: dental affinities among late Paleolithic through Christian-era Nubians.

PubMed

Irish, Joel D

2005-11-01

The present study revisits a subject that has been a source of long-standing bioarchaeological contention, namely, estimation of Nubian population origins and affinities. Using the Arizona State University dental anthropology system, frequencies of 36 crown, root, and intraoral osseous discrete traits in 12 late Pleistocene through early historic Nubian samples were recorded and analyzed. Specifically, intersample phenetic affinities, and an indication of which traits are most important in driving this variation, were determined through the application of correspondence analysis and the mean measure of divergence distance statistic. The results support previous work by the author and others indicating that population discontinuity, in the form of replacement or significant gene flow into an existing gene pool, occurred sometime after the Pleistocene. This analysis now suggests that the break occurred before the Final Neolithic. Samples from the latter through Christian periods exhibit relative homogeneity, which implies overall post-Pleistocene diachronic and regional population continuity. Yet there are several perceptible trends among these latter samples that: 1) are consistent with documented Nubian population history, 2) enable the testing of several existing peopling hypotheses, and 3) allow the formulation of new hypotheses, including a suggestion of two post-Pleistocene subgroups predicated on an age-based sample dichotomy. Copyright 2005 Wiley-Liss, Inc

Hydroxyl Radical Fluorescence and Quantum Yield Following Lyman-α Photoexcitation of Water Vapor in a Room Temperature Cell and Cooled in a Supersonic Expansion.

PubMed

Young, Justin W; Booth, Ryan S; Vogelhuber, Kristen M; Stearns, Jaime A; Annesley, Christopher J

2018-06-28

Photoexcitation of water by Lyman-α (121.6 nm) induces a dissociation reaction that produces OH(A 2 Σ + ) + H. Despite this reaction being part of numerous studies, a combined understanding of the product and fluorescence yields is still lacking. Here, the rotational and vibrational distributions of OH(A) are determined from dispersed fluorescence following photoexcitation of both room-temperature and jet-cooled water vapor, for the first time in the same experiment. This work compares new data of state-resolved fluorescence with literature molecular branching ratios and brings previous studies into agreement through careful consideration of OH(A) fluorescent and predissociation lifetimes and confirms a fluorescent quantum yield of 8%. Comparison of the room-temperature and jet-cooled OH(A) populations indicate the temperature of H 2 O prior to excitation has subtle effects on the OH(A) population distribution, such as altering the rotational distribution in the ν' = 0 population and affecting the population in the ν' = 1 state. These results indicate jet-cooled water vapor may have a 1% higher fluorescence quantum yield compared to room-temperature water vapor.

Aspiration dynamics in structured population acts as if in a well-mixed one.

PubMed

Du, Jinming; Wu, Bin; Wang, Long

2015-01-26

Understanding the evolution of human interactive behaviors is important. Recent experimental results suggest that human cooperation in spatial structured population is not enhanced as predicted in previous works, when payoff-dependent imitation updating rules are used. This constraint opens up an avenue to shed light on how humans update their strategies in real life. Studies via simulations show that, instead of comparison rules, self-evaluation driven updating rules may explain why spatial structure does not alter the evolutionary outcome. Though inspiring, there is a lack of theoretical result to show the existence of such evolutionary updating rule. Here we study the aspiration dynamics, and show that it does not alter the evolutionary outcome in various population structures. Under weak selection, by analytical approximation, we find that the favored strategy in regular graphs is invariant. Further, we show that this is because the criterion under which a strategy is favored is the same as that of a well-mixed population. By simulation, we show that this holds for random networks. Although how humans update their strategies is an open question to be studied, our results provide a theoretical foundation of the updating rules that may capture the real human updating rules.

Chemical analysis of essential oils from different parts of Ferula communis L. growing in central Italy.

PubMed

Maggi, Filippo; Papa, Fabrizio; Dall'Acqua, Stefano; Nicoletti, Marcello

2016-01-01

Ferula communis is a showy herbaceous plant typical of the Mediterranean area where it is used as a traditional medicine. The plant is a source of bioactive compounds such as daucane sesquiterpenes and prenylated coumarins. In Italy, most of phytochemical studies focused on Sardinian populations where poisonous and nonpoisonous chemotypes were found, while investigations on peninsular populations are scarce. In this work, we report the chemical characterisation of the essential oils obtained from different parts of F. communis growing in central Italy. The chemical profiles of the plant parts, as detected by GC-FID and GC-MS, were different from each other and from those reported in insular populations. Notably, α-pinene (10.5%), γ-terpinene (7.6%) and hedycariol (8.4%) were the major volatile constituents in flowers; α-pinene (55.9%), β-pinene (16.8%) and myrcene (5.9%) in fruits; β-eudesmol (12.1%), α-eudesmol (12.1%) and hedycariol (10.3%) in leaves; (E)-β-farnesene (9.5%), β-cubebene (8.2%) and (E)-caryophyllene (7.2%) in roots. The volatile profiles detected did not allow to classify the investigated central Italy population into the poisonous and nonpoisonous chemotypes previously described in Sardinia.

Temporal dynamics and impact of event interactions in cyber-social populations

NASA Astrophysics Data System (ADS)

Zhang, Yi-Qing; Li, Xiang

2013-03-01

The advance of information technologies provides powerful measures to digitize social interactions and facilitate quantitative investigations. To explore large-scale indoor interactions of a social population, we analyze 18 715 users' Wi-Fi access logs recorded in a Chinese university campus during 3 months, and define event interaction (EI) to characterize the concurrent interactions of multiple users inferred by their geographic coincidences—co-locating in the same small region at the same time. We propose three rules to construct a transmission graph, which depicts the topological and temporal features of event interactions. The vertex dynamics of transmission graph tells that the active durations of EIs fall into the truncated power-law distributions, which is independent on the number of involved individuals. The edge dynamics of transmission graph reports that the transmission durations present a truncated power-law pattern independent on the daily and weekly periodicities. Besides, in the aggregated transmission graph, low-degree vertices previously neglected in the aggregated static networks may participate in the large-degree EIs, which is verified by three data sets covering different sizes of social populations with various rendezvouses. This work highlights the temporal significance of event interactions in cyber-social populations.

'We are faced everywhere with a growing population': demographic change and the British state, 1955-64.

PubMed

O' Hara, Glen

2004-01-01

The early 1960s was a period of relative expansion for the welfare state, and the return to the use of planning techniques in macroeconomic policy. This has hitherto been explained by reference to a number of general causes. These have included party political electoral necessity, the need to gain popular support for the cold war by spreading the benefits of liberal capitalism, the power of welfare professionals, the growing realization that the post-war welfare state was not working as well as previously thought, and generational changes in politics and the civil service. Whilst not denying the importance of all these factors, this essay seeks to make clear the importance of another vital element in this story: the implications for the welfare state and the managed economy of the rise in the birth rate, and the perceived' population explosion', of the late 1950s and early 1960s. Statistical estimates are presented here that show just how large the implied expansion of the welfare state, and just how serious the pressure of a growing dependent population, would have been had the population predictions of the early 1930s proved to be accurate.

Bronchitis in men employed in the coke industry

PubMed Central

Walker, D. D.; Archibald, R. M.; Attfield, M. D.

1971-01-01

Walker, D. D., Archibald, R. M., and Attfield, M. D. (1971).Brit. J. industr. Med.,28, 358-363. Bronchitis in men employed in the coke industry. An epidemiological survey to determine the prevalence of bronchitis in men employed at two of the National Coal Board's coking plants is described. Eight hundred and eighty-one men (91%) of the total working population were examined. A strong association was found between bronchitis prevalence and cigarette smoking (P < 0·001). In addition, men who smoked and who were exposed to high temperatures, dust, and fumes in the environment of the coke-ovens had more bronchitis than men who worked elsewhere in the cokeworks (P < 0·02). Both the presence of bronchitis and employment in the environment of the coke-ovens had significant and independent effects on ventilatory capacity. The combination of cigarette smoking and previous employment in a dusty industry also had a significant effect on ventilatory capacity. The investigation suggests that cigarette smoking, and the combination of smoking and pollution from the coke-ovens and previous occupation, appear to be important factors in the aetiology of bronchitis and reduced ventilatory capacity in men employed in the coke manufacturing industry. PMID:5124835

Occupational stress and strain in the Royal Navy 2007.

PubMed

Bridger, R S; Brasher, K; Dew, A; Kilminster, S

2008-12-01

Previous surveys of psychological strain in the Naval Service (NS) have shown higher than expected levels of strain when compared to the general population. To repeat the survey last carried out in 2004 and to obtain further information on the nature of the occupational stressors associated with strain. General Health Questionnaire-12 strain rates and job/life stressors were measured using a Work and Well-Being Questionnaire. Models of strain were developed for male and female personnel in the Royal Navy (RN) and males in the Royal Marines (RM). The response rate was 57%. The psychological strain rate was 31.5% overall. Personnel suffering from strain tended to be 'overcommitted' to work, had low levels of commitment to the NS and had suffered stressful life events (SLEs) in the previous 12 months. Strain rates declined with age and rank in males, but not in females. Strain was significantly positively correlated with levels of overcommitment, effort-reward imbalance (ERI), role conflict, work-family conflict, organizational commitment and exposure to SLEs. Models of strain in the males and females in the RN and in the RM accounted for between 37 and 44% of the variance in strain. The survey provides evidence for both the demand control and ERI models-components of these models contribute independently to strain. High levels of commitment to the organization were associated with lower strain and exposure to SLEs to higher strain.

Settlement scaling and increasing returns in an ancient society

PubMed Central

Ortman, Scott G.; Cabaniss, Andrew H. F.; Sturm, Jennie O.; Bettencourt, Luís M. A.

2015-01-01

A key property of modern cities is increasing returns to scale—the finding that many socioeconomic outputs increase more rapidly than their population size. Recent theoretical work proposes that this phenomenon is the result of general network effects typical of human social networks embedded in space and, thus, is not necessarily limited to modern settlements. We examine the extent to which increasing returns are apparent in archaeological settlement data from the pre-Hispanic Basin of Mexico. We review previous work on the quantitative relationship between population size and average settled area in this society and then present a general analysis of their patterns of monument construction and house sizes. Estimated scaling parameter values and residual statistics support the hypothesis that increasing returns to scale characterized various forms of socioeconomic production available in the archaeological record and are found to be consistent with key expectations from settlement scaling theory. As a consequence, these results provide evidence that the essential processes that lead to increasing returns in contemporary cities may have characterized human settlements throughout history, and demonstrate that increasing returns do not require modern forms of political or economic organization. PMID:26601129

Barriers to Physical Activity in a Mass Transit Population: A Qualitative Study.

PubMed

Das, Bhibha M; Petruzzello, Steven J

2016-01-01

The physical inactivity epidemic continues be one of the greatest public health challenges in contemporary society in the United States. The transportation industry is at greater risk of physical inactivity, compared with individuals in other sectors of the workforce. The aim of this study was to use the Nominal Group Technique, a focus group technique, to examine mass transit employees' perceptions of the barriers to physical activity at their worksite. Three focus groups (n = 31) were conducted to examine mass transit employees' perceptions of barriers to physical activity at the worksite. Salient barriers included (1) changing work schedules, (2) poor weather conditions, and (3) lack of scheduled and timely breaks. Findings were consistent with previous research demonstrating shift work, poor weather, and lack of breaks can negatively impact mass transit employees' ability to be physically active. Although physical activity barriers for this population have been consistent for the last 20 years, public health practice and policy have not changed to address these barriers. Future studies should include conducing focus groups stratified by job classification (eg, operators, maintenance, and clerical) along with implementing and evaluating worksite-based physical activity interventions and policy changes.

Venusian arachnoids revisited

NASA Astrophysics Data System (ADS)

Kostama, V.-P.; Tormanen, T.

The Venusian volcano-tectonic structures have been subject to many classification and characterisation schemes. Several structure-types have been identified (e.g. coronae, novae, arachnoids, calderas, and corona-novae). Of these groups, the relationship of arachnoids and coronae has been complicated, and is a subject to much debate. Some previous works and studies have fused these two categories together, and even promoted the view of non-existence of arachnoids at times. However, based on the recognisable differences in morphology and other characteristics (e.g. size, topography, volcanism), they should be treated as a separate class of structures. In our first global study of the volcano-tectonic features, we found 96 arachnoids [1, 2]. During the reanalysis of the features as a by-product of another study, the arachnoid population was re-evalueted, and more importantly, the identification criteria was rechecked. The revised population increases the arachnoid number to 130 features. The work also produced many examples of features that can be considered as transitional forms between different morphological groups. [1] Kostama, V.-P., M. Aittola, LPSC XXXII, Abstract#1185, 2001a. [2] Kostama, V.-P., M. Aittola, The Catalogue of Venusian Arachnoids, Coronae and Novae, http://cc.oulu.fi/tati/JR/Venus/volcanotectonics/catalogue.html, 2001b.

Executive Functioning in Pediatric Chronic Pain: Do Deficits Exist?

PubMed

Weiss, Karen E; Harbeck-Weber, Cynthia; Zaccariello, Michael J; Kimondo, Jacqueline N; Harrison, Tracy E; Bruce, Barbara K

2018-01-01

Despite ample research documenting deficits in executive functioning for adults with chronic pain, the literature on pediatric patients with chronic pain is limited and provides mixed results. The current study sought to further investigate the nature of executive dysfunction in this population and also examine the relationships between pain intensity, duration, and catastrophizing with sustained attention, working memory, and self- and parent-report of executive functioning. Pediatric pain clinic and rehabilitation program. Forty adolescents with chronic pain and their parents participated in this study. Participants completed neuropsychological measures and standardized self-report questionnaires during a 45- to 60-minute testing session. Fifty percent of this sample of adolescents with chronic pain demonstrated significant difficulties on at least one measure, with nine participants indicating difficulties on multiple measures. Pain significantly increased during the testing session. Pain variables of intensity, duration, and catastrophizing are related to sustained attention and working memory. This study adds support to previous findings suggesting subclinical struggles with executive functioning for adolescents with chronic pain. One-half of the sample indicated difficulties in either sustained attention and/or working memory. Future studies that would more thoroughly examine more complex executive functioning skills in this population would be helpful to further guide multidisciplinary treatment of these patients, particularly regarding whether or not school accommodations are warranted. © 2017 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

A nonparametric method to generate synthetic populations to adjust for complex sampling design features.

PubMed

Dong, Qi; Elliott, Michael R; Raghunathan, Trivellore E

2014-06-01

Outside of the survey sampling literature, samples are often assumed to be generated by a simple random sampling process that produces independent and identically distributed (IID) samples. Many statistical methods are developed largely in this IID world. Application of these methods to data from complex sample surveys without making allowance for the survey design features can lead to erroneous inferences. Hence, much time and effort have been devoted to develop the statistical methods to analyze complex survey data and account for the sample design. This issue is particularly important when generating synthetic populations using finite population Bayesian inference, as is often done in missing data or disclosure risk settings, or when combining data from multiple surveys. By extending previous work in finite population Bayesian bootstrap literature, we propose a method to generate synthetic populations from a posterior predictive distribution in a fashion inverts the complex sampling design features and generates simple random samples from a superpopulation point of view, making adjustment on the complex data so that they can be analyzed as simple random samples. We consider a simulation study with a stratified, clustered unequal-probability of selection sample design, and use the proposed nonparametric method to generate synthetic populations for the 2006 National Health Interview Survey (NHIS), and the Medical Expenditure Panel Survey (MEPS), which are stratified, clustered unequal-probability of selection sample designs.

A nonparametric method to generate synthetic populations to adjust for complex sampling design features

PubMed Central

Dong, Qi; Elliott, Michael R.; Raghunathan, Trivellore E.

2017-01-01

Outside of the survey sampling literature, samples are often assumed to be generated by a simple random sampling process that produces independent and identically distributed (IID) samples. Many statistical methods are developed largely in this IID world. Application of these methods to data from complex sample surveys without making allowance for the survey design features can lead to erroneous inferences. Hence, much time and effort have been devoted to develop the statistical methods to analyze complex survey data and account for the sample design. This issue is particularly important when generating synthetic populations using finite population Bayesian inference, as is often done in missing data or disclosure risk settings, or when combining data from multiple surveys. By extending previous work in finite population Bayesian bootstrap literature, we propose a method to generate synthetic populations from a posterior predictive distribution in a fashion inverts the complex sampling design features and generates simple random samples from a superpopulation point of view, making adjustment on the complex data so that they can be analyzed as simple random samples. We consider a simulation study with a stratified, clustered unequal-probability of selection sample design, and use the proposed nonparametric method to generate synthetic populations for the 2006 National Health Interview Survey (NHIS), and the Medical Expenditure Panel Survey (MEPS), which are stratified, clustered unequal-probability of selection sample designs. PMID:29200608

SimBA: simulation algorithm to fit extant-population distributions.

PubMed

Parida, Laxmi; Haiminen, Niina

2015-03-14

Simulation of populations with specified characteristics such as allele frequencies, linkage disequilibrium etc., is an integral component of many studies, including in-silico breeding optimization. Since the accuracy and sensitivity of population simulation is critical to the quality of the output of the applications that use them, accurate algorithms are required to provide a strong foundation to the methods in these studies. In this paper we present SimBA (Simulation using Best-fit Algorithm) a non-generative approach, based on a combination of stochastic techniques and discrete methods. We optimize a hill climbing algorithm and extend the framework to include multiple subpopulation structures. Additionally, we show that SimBA is very sensitive to the input specifications, i.e., very similar but distinct input characteristics result in distinct outputs with high fidelity to the specified distributions. This property of the simulation is not explicitly modeled or studied by previous methods. We show that SimBA outperforms the existing population simulation methods, both in terms of accuracy as well as time-efficiency. Not only does it construct populations that meet the input specifications more stringently than other published methods, SimBA is also easy to use. It does not require explicit parameter adaptations or calibrations. Also, it can work with input specified as distributions, without an exemplar matrix or population as required by some methods. SimBA is available at http://researcher.ibm.com/project/5669 .

Assessing the Relationship of Ancient and Modern Populations

PubMed Central

Schraiber, Joshua G.

2018-01-01

Genetic material sequenced from ancient samples is revolutionizing our understanding of the recent evolutionary past. However, ancient DNA is often degraded, resulting in low coverage, error-prone sequencing. Several solutions exist to this problem, ranging from simple approach, such as selecting a read at random for each site, to more complicated approaches involving genotype likelihoods. In this work, we present a novel method for assessing the relationship of an ancient sample with a modern population, while accounting for sequencing error and postmortem damage by analyzing raw reads from multiple ancient individuals simultaneously. We show that, when analyzing SNP data, it is better to sequence more ancient samples to low coverage: two samples sequenced to 0.5× coverage provide better resolution than a single sample sequenced to 2× coverage. We also examined the power to detect whether an ancient sample is directly ancestral to a modern population, finding that, with even a few high coverage individuals, even ancient samples that are very slightly diverged from the modern population can be detected with ease. When we applied our approach to European samples, we found that no ancient samples represent direct ancestors of modern Europeans. We also found that, as shown previously, the most ancient Europeans appear to have had the smallest effective population sizes, indicating a role for agriculture in modern population growth. PMID:29167200

Improving detection of dementia in Asian patients with low education: combining the Mini-Mental State Examination and the Informant Questionnaire on Cognitive Decline in the Elderly.

PubMed

Narasimhalu, Kaavya; Lee, June; Auchus, Alexander P; Chen, Christopher P L H

2008-01-01

Previous work combining the Mini-Mental State Examination (MMSE) and Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) has been conducted in western populations. We ascertained, in an Asian population, (1) the best method of combining the tests, (2) the effects of educational level, and (3) the effect of different dementia etiologies. Data from 576 patients were analyzed (407 nondemented controls, 87 Alzheimer's disease and 82 vascular dementia patients). Sensitivity, specificity and AUC values were obtained using three methods, the 'And' rule, the 'Or' rule, and the 'weighted sum' method. The 'weighted sum' rule had statistically superior AUC and specificity results, while the 'Or' rule had the best sensitivity results. The IQCODE outperformed the MMSE in all analyses. Patients with no education benefited more from combined tests. There was no difference between Alzheimer's disease and vascular dementia populations in the predictive value of any of the combined methods. We recommend that the IQCODE be used to supplement the MMSE whenever available and that the 'weighted sum' method be used to combine the MMSE and the IQCODE, particularly in populations with low education. As the study population selected may not be representative of the general population, further studies are required before generalization to nonclinical samples. (c) 2007 S. Karger AG, Basel.

Distinctive role of income in the all-cause mortality among working age migrants and the settled population in Finland: A follow-up study from 2001 to 2014.

PubMed

Patel, Kishan; Kouvonen, Anne; Koskinen, Aki; Kokkinen, Lauri; Donnelly, Michael; O'Reilly, Dermot; Vaananen, Ari

2018-03-01

Although income level may play a significant part in mortality among migrants, previous research has not focused on the relationship between income, migration and mortality risk. The aim of this register study was to compare all-cause mortality by income level between different migrant groups and the majority settled population of Finland. A random sample was drawn of 1,058,391 working age people (age range 18-64 years; 50.4% men) living in Finland in 2000 and linked to mortality data from 2001 to 2014. The data were obtained from Statistics Finland. Cox proportional hazards models were used to investigate the association between region of origin and all-cause mortality in low- and high-income groups. The risk for all-cause mortality was significantly lower among migrants than among the settled majority population (hazards ratio (HR) 0.57; 95% confidence interval (CI) 0.53-0.62). After adjustment for age, sex, marital status, employment status and personal income, the risk of mortality was significantly reduced for low-income migrants compared with the settled majority population with a low income level (HR 0.46; 95% CI 0.42-0.50) and for high-income migrants compared with the high-income settled majority (HR 0.81; 95% CI 0.69-0.95). Results comparing individual high-income migrant groups and the settled population were not significant. Low-income migrants from Africa, the Middle East and Asia had the lowest mortality risk of any migrant group studied (HR 0.32; 95% CI 0.27-0.39). Particularly low-income migrants seem to display a survival advantage compared with the corresponding income group in the settled majority population. Downward social mobility, differences in health-related lifestyles and the healthy migrant effect may explain this phenomenon.

Social contact networks and disease eradicability under voluntary vaccination.

PubMed

Perisic, Ana; Bauch, Chris T

2009-02-01

Certain theories suggest that it should be difficult or impossible to eradicate a vaccine-preventable disease under voluntary vaccination: Herd immunity implies that the individual incentive to vaccinate disappears at high coverage levels. Historically, there have been examples of declining coverage for vaccines, such as MMR vaccine and whole-cell pertussis vaccine, that are consistent with this theory. On the other hand, smallpox was globally eradicated by 1980 despite voluntary vaccination policies in many jurisdictions. Previous modeling studies of the interplay between disease dynamics and individual vaccinating behavior have assumed that infection is transmitted in a homogeneously mixing population. By comparison, here we simulate transmission of a vaccine-preventable SEIR infection through a random, static contact network. Individuals choose whether to vaccinate based on infection risks from neighbors, and based on vaccine risks. When neighborhood size is small, rational vaccinating behavior results in rapid containment of the infection through voluntary ring vaccination. As neighborhood size increases (while the average force of infection is held constant), a threshold is reached beyond which the infection can break through partially vaccinated rings, percolating through the whole population and resulting in considerable epidemic final sizes and a large number vaccinated. The former outcome represents convergence between individually and socially optimal outcomes, whereas the latter represents their divergence, as observed in most models of individual vaccinating behavior that assume homogeneous mixing. Similar effects are observed in an extended model using smallpox-specific natural history and transmissibility assumptions. This work illustrates the significant qualitative differences between behavior-infection dynamics in discrete contact-structured populations versus continuous unstructured populations. This work also shows how disease eradicability in populations where voluntary vaccination is the primary control mechanism may depend partly on whether the disease is transmissible only to a few close social contacts or to a larger subset of the population.

[Acute lumbago due to the manual lifting of patients in wards: prevalence and incidence data].

PubMed

Colombini, D; Cianci, E; Panciera, D; Martinelli, M; Venturi, E; Giammartini, P; Ricci, M G; Menoni, O; Battevi, N

1999-01-01

The aim of the study was to measure the occurrence (prevalence and incidence) of episodes of acute low back pain (definite effect) in a wide sample of health workers assisting disabled patients. A questionnaire was used for the study both of true acute low back pain and of episodes of ingravescent low back pain controlled pharmacologically at the onset. The questionnaire identified overall acute and pharmacologically controlled episodes occurring in the previous 12 months, both in the course of work and over the whole life of the subject. Appropriately trained operators administered the questionnaire to 551 subjects; 481 valid answer cards were obtained from 372 females and 109 males working in medical, orthopaedic and geriatric departments. 75.4% of the sample had high exposure index levels for patient lifting. The prevalence of true acute low back pain was 9% in males and 11% in females referred to the previous 12 months. Taking acute true and pharmacologically controlled low back pain together the prevalences rose to 13.8% for males and 26.9% in females. Data from the reference populations showed that acute low back pain did not exceed 3% on average in the previous year. Since work seniority in the hospital wards was known, the incidences were calculated, giving 7.9% in females and 5.29% in males for acute low back pain, and 19% in females and 3.49% in males for pharmacologically controlled low back pain. Considering the number of episodes in 100 workers/year, acute low back pain alone reached prevalences of 13-14%. This therefore appears to confirm the positive ratio between episodes of low back pain and duties involving assistance to disabled patients.

Morbidity ranking of U.S. workers employed in 206 occupations: the National Health Interview Survey (NHIS) 1986-1994.

PubMed

Lee, David J; Fleming, Lora E; Gómez-Marín, Orlando; LeBlanc, William G; Arheart, Kristopher L; Caban, Alberto J; Christ, Sharon L; Chung-Bridges, Katherine; Pitman, Terry

2006-02-01

The objective of this study was to rank U.S. occupations by worker morbidity. From 1986 through 1994, morbidity information was collected on over 410,000 U.S. workers who participated in the National Health Interview Survey, an annual household survey representative of the U.S. civilian noninstitutionalized population. A multivariate adjusted logistic regression morbidity summary score was created for each worker group based on seven indicators: days of restricted activity, bedrest, and missed work in the previous 2 weeks; doctor visits and hospitalizations in the previous 12 months; reported health conditions; and health status. Worker groups reporting the greatest morbidity included social workers, inspectors, postal clerks, psychologists, and grinding machine operators; worker groups reporting the least morbidity included dentists, pilots, physicians, pharmacists, and dietitians. These findings aid in the identification of worker groups that require increased attention for morbidity research and prevention.

Incidence of Chronic and Other Knee Pain in Relation to Occupational Risk Factors in a Large Working Population.

PubMed

Herquelot, Eléonore; Bodin, Julie; Petit, Audrey; Ha, Catherine; Leclerc, Annette; Goldberg, Marcel; Zins, Marie; Roquelaure, Yves; Descatha, Alexis

2015-07-01

The aim of this study was to estimate the incidence of chronic and other knee pain (KP) in relation to occupational and personal risk factors among workers representative of a general working population. Of 3710 workers in a French region included in a surveillance network for musculoskeletal disorders (2002-2005), 2332 completed a follow-up questionnaire in 2007-2009 (Cosali cohort). The questionnaires included questions on musculoskeletal symptoms, and personal and occupational exposure. Incident cases of KP in 2007-2009 (i.e. with KP at follow-up but not at baseline) were dichotomized into chronic KP (>30 days in the previous year) and other KP. Associations between incident KP and personal and occupational factors at baseline were studied separately according to sex using multinomial logistic regression. Of the 1616 respondents without KP at baseline, 122 (7.5%) reported chronic KP and 243 (15.0%) reported other KP. The incidence rate of chronic KP was estimated at 19.6 per 1000 worker-years (95% CI: 16.3-23.5). After adjustment for age and body mass index, significant associations were found between incident chronic KP and handling loads >4kg [odds ratio (OR) 2.1 (1.2-3.6) for men, OR 2.3 (1.1-5.0) for women] and kneeling >2h a day for men [OR 1.8 (1.0-3.0)]. This study highlights the high frequency of chronic KP in the working population and the role of occupational factors in its incidence, in particular those kneeling and handling loads. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Low Control and High Demands at Work as Risk Factors for Suicide: An Australian National Population-Level Case-Control Study.

PubMed

Milner, Allison; Spittal, Matthew J; Pirkis, Jane; Chastang, Jean-François; Niedhammer, Isabelle; LaMontagne, Anthony D

2017-04-01

Previous research suggests that psychosocial job stressors may be plausible risk factors for suicide. This study assessed the relationship between psychosocial job stressors and suicide mortality across the Australian population. We developed a job exposure matrix to objectively measure job stressors across the working population. Suicide data came from a nationwide coronial register. Living controls were selected from a nationally representative cohort study. Incidence density sampling was used to ensure that controls were sampled at the time of death of each case. The period of observation for both cases and controls was 2001 to 2012. We used multilevel logistic regression to assess the odds of suicide in relation to 2 psychosocial job stressors (job control and job demands), after matching for age, sex, and year of death/survey and adjusting for socioeconomic status. Across 9,010 cases and 14,007 matched controls, our results suggest that low job control (odds ratio [OR], 1.35; 95% confidence interval [CI], 1.26-1.44; p < .001) and high job demands (OR, 1.36; 95% CI, 1.26-1.46; p < .001) were associated with increased odds of male suicide after adjusting for socioeconomic status. High demands were associated with lower odds of female suicide (OR, 0.81; 95% CI, 0.72-0.92; p = .002). It seems that adverse experiences at work are a risk factor for male suicide while not being associated with an elevated risk among females. Future studies on job stressors and suicide are needed, both to further understand the biobehavioral mechanisms explaining the link between job stress and suicide, and to inform targeted prevention initiatives.

Molecular phylogeography and cryptic speciation in the mosses, Mielichhoferia elongata and M. mielichhoferiana (Bryaceae).

PubMed

Shaw, A J

2000-05-01

Nucleotide sequence variation in the ITS1-5.8S-ITS2 region of nuclear ribosomal DNA (nrDNA) from 70 populations of Mielichhoferia elongata and M. mielichhoferiana, plus two outgroup species, was analysed using maximum parsimony and maximum likelihood methods. High levels of nucleotide substitution and numerous insertion-deletion events were detected within and between the two species. M. elongata is monophyletic with regard to nrDNA variation, but M. mielichhoferiana is paraphyletic. (M. elongata is nested within it.) A clade within M. mielichhoferiana provides evidence of vicariance, with North American and Scandinavian sister groups of populations. Two major clades are resolved in M. elongata by sequence data that are completely congruent with previous isozyme work. One clade includes populations from both North America and Europe whereas the other is strictly North American. These two clades, resolved by multiple independent loci, clearly represent cryptic species within the morphologically uniform M. elongata. Certain geographical areas, most notably southwestern Colorado in Ouray and San Juan Counties, harbour diverse populations of M. elongata with distinct phylogenetic and phylogeographical histories. Morphologically indistinguishable but phylogenetically distant populations were detected a few metres apart at one site. In contrast, all populations collected over hundreds of kilometres in California belong to a single clade. Arctic North American populations belong to a clade that includes disjunct populations in Alaska, northern Ellesmere Island, and the northeastern USA, but not subarctic Swedish populations, which are more closely related to plants from the Rocky Mountains. Morphological uniformity belies complex infraspecific phylogenetic patterns within M. elongata and M. mielichhoferiana.

Comparison of Intrinsic Rate of Different House Fly Densities in a Simulated Condition: A Prediction for House Fly Population and Control Threshold.

PubMed

Ong, Song-Quan; Ahmad, Hamdan; Jaal, Zairi; Rus, Adanan; Fadzlah, Fadhlina Hazwani Mohd

2017-01-01

Determining the control threshold for a pest is common prior to initiating a pest control program; however, previous studies related to the house fly control threshold for a poultry farm are insufficient for determining such a threshold. This study aimed to predict the population changes of house fly population by comparing the intrinsic rate of increase (r m ) for different house fly densities in a simulated system. This study first defined the knee points of a known population growth curve as a control threshold by comparing the r m of five densities of house flies in a simulated condition. Later, to understand the interactions between the larval and adult populations, the correlation between larval and adult capacity rate (r c ) was studied. The r m values of 300- and 500-fly densities were significantly higher compared with the r m values at densities of 50 and 100 flies. This result indicated their representative indices as candidates for a control threshold. The r c of larval and adult populations were negatively correlated with densities of fewer than 300 flies; this implicated adult populations with fewer than 300 flies as declining while the larval population was growing; therefore, control approaches should focus on the immature stages. The results in the present study suggest a control threshold for house fly populations. Future works should focus on calibrating the threshold indices in field conditions. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Rovibrational optical pumping of a molecular beam

NASA Astrophysics Data System (ADS)

Cournol, A.; Pillet, P.; Lignier, H.; Comparat, D.

2018-03-01

The preparation of molecules in well-defined internal states is essential for various studies in fundamental physics and physical chemistry. It is thus of particular interest to find methods that increase the brightness of molecular beams. Here, we report on rotational and vibrational pumpings of a supersonic beam of barium monofluoride molecules. With respect to previous works, the time scale of optical vibrational pumping has been greatly reduced by enhancing the spectral power density in the vicinity of the appropriate molecular transitions. We demonstrate a complete transfer of the rovibrational populations lying in v″=1 -3 into the vibrational ground-state v″=0 . Rotational pumping, which requires efficient vibrational pumping, has been also demonstrated. According to a Maxwell-Boltzmann description, the rotational temperature of our sample has been reduced by a factor of ˜8 . In this fashion, the population of the lowest rotational levels increased by more than one order of magnitude.

A sequential coalescent algorithm for chromosomal inversions

PubMed Central

Peischl, S; Koch, E; Guerrero, R F; Kirkpatrick, M

2013-01-01

Chromosomal inversions are common in natural populations and are believed to be involved in many important evolutionary phenomena, including speciation, the evolution of sex chromosomes and local adaptation. While recent advances in sequencing and genotyping methods are leading to rapidly increasing amounts of genome-wide sequence data that reveal interesting patterns of genetic variation within inverted regions, efficient simulation methods to study these patterns are largely missing. In this work, we extend the sequential Markovian coalescent, an approximation to the coalescent with recombination, to include the effects of polymorphic inversions on patterns of recombination. Results show that our algorithm is fast, memory-efficient and accurate, making it feasible to simulate large inversions in large populations for the first time. The SMC algorithm enables studies of patterns of genetic variation (for example, linkage disequilibria) and tests of hypotheses (using simulation-based approaches) that were previously intractable. PMID:23632894

Stability diagram for the forced Kuramoto model.

PubMed

Childs, Lauren M; Strogatz, Steven H

2008-12-01

We analyze the periodically forced Kuramoto model. This system consists of an infinite population of phase oscillators with random intrinsic frequencies, global sinusoidal coupling, and external sinusoidal forcing. It represents an idealization of many phenomena in physics, chemistry, and biology in which mutual synchronization competes with forced synchronization. In other words, the oscillators in the population try to synchronize with one another while also trying to lock onto an external drive. Previous work on the forced Kuramoto model uncovered two main types of attractors, called forced entrainment and mutual entrainment, but the details of the bifurcations between them were unclear. Here we present a complete bifurcation analysis of the model for a special case in which the infinite-dimensional dynamics collapse to a two-dimensional system. Exact results are obtained for the locations of Hopf, saddle-node, and Takens-Bogdanov bifurcations. The resulting stability diagram bears a striking resemblance to that for the weakly nonlinear forced van der Pol oscillator.

Children who murder: a review.

PubMed

Shumaker, D M; Prinz, R J

2000-06-01

Despite considerable research on juvenile homicide, pre-adolescent homicide offenders have received less attention. This paper reviews the existing literature on preteen murderers in order to characterize the current state of research knowledge about this population, and draws on some of the work on adolescent homicide as well. The analysis of this literature considers historical context, methodological issues, previous attempts to classify youthful homicide offenders, and predictors of preteen homicidal behavior. While there is a high degree of heterogeneity within this population, several developmental similarities emerged across cases that were associated with the perpetration of homicide by preteens. A high percentage of preteen homicide offenders come from homes characterized by physical abuse, domestic violence, poor or absent parenting, and overall instability. Gun availability may have been a facilitating factor. Support for different etiologies of preteen versus adolescent homicide is weak. Recommendations for future research directions are offered.

The Effects of Hemodynamic Shear Stress on Stemness of Acute Myelogenous Leukemia (AML)

NASA Astrophysics Data System (ADS)

Raddatz, Andrew; Triantafillu, Ursula; Kim, Yonghyun (John)

2015-11-01

Cancer stem cells (CSCs) have recently been identified as the root cause of tumors generated from cancer cell populations. This is because these CSCs are drug-resistant and have the ability to self-renew and differentiate. Current methods of culturing CSCs require much time and money, so cancer cell culture protocols, which maximize yield of CSCs are needed. It was hypothesized that the quantity of Acute myelogenous leukemia stem cells (LSCs) would increase after applying shear stress to the leukemia cells based on previous studies with breast cancer in bioreactors. The shear stress was applied by pumping the cells through narrow tubing to mimic the in vivo bloodstream environment. In support of the hypothesis, shear stress was found to increase the amount of LSCs in a given leukemia population. This work was supported by NSF REU Site Award 1358991.

Identification of a primordial asteroid family constrains the original planetesimal population.

PubMed

Delbo', Marco; Walsh, Kevin; Bolin, Bryce; Avdellidou, Chrysa; Morbidelli, Alessandro

2017-09-08

A quarter of known asteroids is associated with more than 100 distinct asteroid families, meaning that these asteroids originate as impact fragments from the family parent bodies. The determination of which asteroids of the remaining population are members of undiscovered families, or accreted as planetesimals from the protoplanetary disk, would constrain a critical phase of planetary formation by unveiling the unknown planetesimal size distribution. We discovered a 4-billion-year-old asteroid family extending across the entire inner part of the main belt whose members include most of the dark asteroids previously unlinked to families. This allows us to identify some original planetesimals, which are all larger than 35 kilometers, supporting the view of asteroids being born big. Their number matches the known distinct meteorite parent bodies. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Two strains of male-killing Wolbachia in a ladybird, Coccinella undecimpunctata, from a hot climate.

PubMed

Elnagdy, Sherif; Messing, Susan; Majerus, Michael E N

2013-01-01

Ladybirds are a hot-spot for the invasion of male-killing bacteria. These maternally inherited endosymbionts cause the death of male host embryos, to the benefit of female sibling hosts and the bacteria that they contain. Previous studies have shown that high temperatures can eradicate male-killers from ladybirds, leaving the host free from infection. Here we report the discovery of two maternally inherited sex ratio distorters in populations of a coccinellid, Coccinella undecimpunctata, from a hot lowland region of the Middle East. DNA sequence analysis indicates that the male killing is the result of infection by Wolbachia, that the trait is tetracycline sensitive, and that two distinct strains of Wolbachia co-occur within one beetle population. We discuss the implications of these findings for theories of male-killing and suggest avenues for future field-work on this system.

Two Strains of Male-Killing Wolbachia in a Ladybird, Coccinella undecimpunctata, from a Hot Climate

PubMed Central

Elnagdy, Sherif; Messing, Susan

2013-01-01

Ladybirds are a hot-spot for the invasion of male-killing bacteria. These maternally inherited endosymbionts cause the death of male host embryos, to the benefit of female sibling hosts and the bacteria that they contain. Previous studies have shown that high temperatures can eradicate male-killers from ladybirds, leaving the host free from infection. Here we report the discovery of two maternally inherited sex ratio distorters in populations of a coccinellid, Coccinella undecimpunctata, from a hot lowland region of the Middle East. DNA sequence analysis indicates that the male killing is the result of infection by Wolbachia, that the trait is tetracycline sensitive, and that two distinct strains of Wolbachia co-occur within one beetle population. We discuss the implications of these findings for theories of male-killing and suggest avenues for future field-work on this system. PMID:23349831

Genome-Wide Association Study Reveals a New QTL for Salinity Tolerance in Barley (Hordeum vulgare L.)

PubMed Central

Fan, Yun; Zhou, Gaofeng; Shabala, Sergey; Chen, Zhong-Hua; Cai, Shengguan; Li, Chengdao; Zhou, Meixue

2016-01-01

Salinity stress is one of the most severe abiotic stresses that affect agricultural production. Genome wide association study (GWAS) has been widely used to detect genetic variations in extensive natural accessions with more recombination and higher resolution. In this study, 206 barley accessions collected worldwide were genotyped with 408 Diversity Arrays Technology (DArT) markers and evaluated for salinity stress tolerance using salinity tolerance score – a reliable trait developed in our previous work. GWAS for salinity tolerance had been conducted through a general linkage model and a mixed linkage model based on population structure and kinship. A total of 24 significant marker-trait associations were identified. A QTL on 4H with the nearest marker of bPb-9668 was consistently detected in all different methods. This QTL has not been reported before and is worth to be further confirmed with bi-parental populations. PMID:27446173

Whole parasite blood stage malaria vaccines: a convergence of evidence.

PubMed

McCarthy, James S; Good, Michael F

2010-01-01

There is a growing realization of the limitations of recombinant protein-based malaria vaccines. This, coupled with a better understanding of the protective immunity to malaria, both in animal models and in naturally exposed human populations and experimentally infected volunteers, as well as the increased capacity to manipulate parasites provides new impetus to evaluate whole blood stage parasite approaches to malaria vaccine development. In this review previous studies in rodents and primates of whole killed and attenuated blood stage vaccines, and recent work on the effect of genetically attenuated parasites on immunity in rodent models of blood stage immunity are discussed. The relationship between these findings and what is now known about protective immunity in human populations, specifically against the blood stages of the parasite lifecycle is discussed and recent findings from human experimental infection are be reviewed. Finally, the prospect for and impediments to the development whole blood stage parasites are reviewed.

Fine mapping of a quantitative resistance gene for gray leaf spot of maize (Zea mays L.) derived from teosinte (Z. mays ssp. parviglumis).

PubMed

Zhang, Xinye; Yang, Qin; Rucker, Elizabeth; Thomason, Wade; Balint-Kurti, Peter

2017-06-01

In this study we mapped the QTL Qgls8 for gray leaf spot (GLS) resistance in maize to a ~130 kb region on chromosome 8 including five predicted genes. In previous work, using near isogenic line (NIL) populations in which segments of the teosinte (Zea mays ssp. parviglumis) genome had been introgressed into the background of the maize line B73, we had identified a QTL on chromosome 8, here called Qgls8, for gray leaf spot (GLS) resistance. We identified alternate teosinte alleles at this QTL, one conferring increased GLS resistance and one increased susceptibility relative to the B73 allele. Using segregating populations derived from NIL parents carrying these contrasting alleles, we were able to delimit the QTL region to a ~130 kb (based on the B73 genome) which encompassed five predicted genes.

Personnel's health surveillance at work: effect of age, body mass index, and shift work on mental workload and work ability index.

PubMed

Safari, Shahram; Akbari, Jafar; Kazemi, Meghdad; Mououdi, Mohammad Amin; Mahaki, Behzad

2013-01-01

Two great changes in developed countries are taking place: populations are ageing and becoming increasingly overweight. Combination of these factors with shift work is a risk factor for work ability and mental workload that are dynamic processes which change greatly throughout an individual's work life. The aim of this study was to investigate mental workload and work ability in textile workers and to identify factors which affect work ability and mental workload. This cross-sectional study was carried out among 194 male workers in textile industry. Employees based on their job group and work conditions have been divided into 6 categories. They completed work ability index and mental workload questionnaires during three work shifts. Body mass index (BMI) and demographic details were recorded. All of the participants rated their work ability as moderate with high mental workload. The mean WAI and mental workload in age group were significant. The mean BMI was 25.5 kg/m(2) (standard deviation 4.1) and the mean age was 40.22 years. There was a statistically significant correlation between work ability index and shift work. Unlike the previous study, a decrease point in WAI started in early age that may be due to life-style work and another psychological factor; on the other hand, NASA-TLX revealed high score in six subscales that can be another reason for low WAI.

Personnel's Health Surveillance at Work: Effect of Age, Body Mass Index, and Shift Work on Mental Workload and Work Ability Index

PubMed Central

Safari, Shahram; Akbari, Jafar; Kazemi, Meghdad; Mououdi, Mohammad Amin; Mahaki, Behzad

2013-01-01

Introduction. Two great changes in developed countries are taking place: populations are ageing and becoming increasingly overweight. Combination of these factors with shift work is a risk factor for work ability and mental workload that are dynamic processes which change greatly throughout an individual's work life. The aim of this study was to investigate mental workload and work ability in textile workers and to identify factors which affect work ability and mental workload. Methods. This cross-sectional study was carried out among 194 male workers in textile industry. Employees based on their job group and work conditions have been divided into 6 categories. They completed work ability index and mental workload questionnaires during three work shifts. Body mass index (BMI) and demographic details were recorded. Results. All of the participants rated their work ability as moderate with high mental workload. The mean WAI and mental workload in age group were significant. The mean BMI was 25.5 kg/m2 (standard deviation 4.1) and the mean age was 40.22 years. There was a statistically significant correlation between work ability index and shift work. Conclusions. Unlike the previous study, a decrease point in WAI started in early age that may be due to life-style work and another psychological factor; on the other hand, NASA-TLX revealed high score in six subscales that can be another reason for low WAI. PMID:23956756

Melasma in Latina patients: cross-cultural adaptation and validation of a quality-of-life questionnaire in Spanish language.

PubMed

Dominguez, Arturo R; Balkrishnan, Rajesh; Ellzey, Allison R; Pandya, Amit G

2006-07-01

Melasma has been shown to have a significant emotional and psychologic effect on affected patients. Although this pigmentary disorder is thought to be more prevalent among Latinos, the effect of melasma on quality of life (QOL) in this population is unknown. The goals of this study were to translate and culturally adapt the previously validated Melasma QOL (MELASQOL) scale into Spanish language, to confirm the new scale's reliability and validity, and to administer the scale to characterize melasma's effect on the health-related QOL of Spanish language-speaking Latino patients. Cross-cultural adaptation of the original questionnaire was performed using previously established guidelines. After pretesting the questionnaire in a group of 30 patients, it was tested in a group of 112 patients recruited from a community outpatient clinic. A Spanish-language health-related QOL assessment battery was also administered for validation purposes. The degree of melasma was determined on clinical examination by the investigator using the Melasma Area and Severity Index. Cross-cultural adaptation of the questionnaire was successful in producing a working and understandable Spanish-language version of the MELASQOL. The Spanish-language MELASQOL scale was internally reliable and demonstrated construct and content validity. The Spanish-language MELASQOL scores of patients with little to no formal education were significantly higher than those with at least a seventh-grade education. Scores were proportional to the length of time a patient had lived with melasma and were higher in patients who had previously sought treatment. Spanish-language MELASQOL score and Melasma Area and Severity Index were shown to be moderately correlated, but no differences were seen according to patient age, marital status, employment, or coexisting medical or psychiatric conditions. Limitations are a lack of data regarding socioeconomic status and limitation to Mexican and Central American female patients. We have developed a semantically equivalent translation of MELASQOL in the Spanish language and have begun to characterize the effects of melasma on the QOL in a population that has not been previously studied. Further studies in larger populations of Spanish language-speaking patients from various geographic and socioeconomic groups are warranted.

The Nearly Neutral and Selection Theories of Molecular Evolution Under the Fisher Geometrical Framework: Substitution Rate, Population Size, and Complexity

PubMed Central

Razeto-Barry, Pablo; Díaz, Javier; Vásquez, Rodrigo A.

2012-01-01

The general theories of molecular evolution depend on relatively arbitrary assumptions about the relative distribution and rate of advantageous, deleterious, neutral, and nearly neutral mutations. The Fisher geometrical model (FGM) has been used to make distributions of mutations biologically interpretable. We explored an FGM-based molecular model to represent molecular evolutionary processes typically studied by nearly neutral and selection models, but in which distributions and relative rates of mutations with different selection coefficients are a consequence of biologically interpretable parameters, such as the average size of the phenotypic effect of mutations and the number of traits (complexity) of organisms. A variant of the FGM-based model that we called the static regime (SR) represents evolution as a nearly neutral process in which substitution rates are determined by a dynamic substitution process in which the population’s phenotype remains around a suboptimum equilibrium fitness produced by a balance between slightly deleterious and slightly advantageous compensatory substitutions. As in previous nearly neutral models, the SR predicts a negative relationship between molecular evolutionary rate and population size; however, SR does not have the unrealistic properties of previous nearly neutral models such as the narrow window of selection strengths in which they work. In addition, the SR suggests that compensatory mutations cannot explain the high rate of fixations driven by positive selection currently found in DNA sequences, contrary to what has been previously suggested. We also developed a generalization of SR in which the optimum phenotype can change stochastically due to environmental or physiological shifts, which we called the variable regime (VR). VR models evolution as an interplay between adaptive processes and nearly neutral steady-state processes. When strong environmental fluctuations are incorporated, the process becomes a selection model in which evolutionary rate does not depend on population size, but is critically dependent on the complexity of organisms and mutation size. For SR as well as VR we found that key parameters of molecular evolution are linked by biological factors, and we showed that they cannot be fixed independently by arbitrary criteria, as has usually been assumed in previous molecular evolutionary models. PMID:22426879

Enhanced Co-Worker Social Support in Isolated Work Groups and Its Mitigating Role on the Work-Family Conflict-Depression Loss Spiral.

PubMed

McTernan, Wesley P; Dollard, Maureen F; Tuckey, Michelle R; Vandenberg, Robert J

2016-03-29

This paper examines a loss spiral model (i.e., reciprocal relationships) between work-family conflict and depression, moderated by co-worker support. We expected that the moderation effect due to co-worker support would be evident among those working in isolation (i.e., mining workers) due to a greater level of intragroup attraction and saliency attributable to the proximity effects. We used a two wave panel study and data from a random population sample of Australian employees (n = 2793, [n = 112 mining, n = 2681 non-mining]). Using structural equation modelling we tested the reciprocal three way interaction effects. In line with our theory, co-worker support buffered the reciprocal relationship between WFC and depression, showing a protective effect in both pathways. These moderation effects were found in the mining industry only suggesting a proximity component moderates the social support buffer hypothesis (i.e., a three way interaction effect). The present paper integrates previous theoretical perspectives of stress and support, and provides insight into the changing dynamics of workplace relationships.

Enhanced Co-Worker Social Support in Isolated Work Groups and Its Mitigating Role on the Work-Family Conflict-Depression Loss Spiral

PubMed Central

McTernan, Wesley P.; Dollard, Maureen F.; Tuckey, Michelle R.; Vandenberg, Robert J.

2016-01-01

This paper examines a loss spiral model (i.e., reciprocal relationships) between work-family conflict and depression, moderated by co-worker support. We expected that the moderation effect due to co-worker support would be evident among those working in isolation (i.e., mining workers) due to a greater level of intragroup attraction and saliency attributable to the proximity effects. We used a two wave panel study and data from a random population sample of Australian employees (n = 2793, [n = 112 mining, n = 2681 non-mining]). Using structural equation modelling we tested the reciprocal three way interaction effects. In line with our theory, co-worker support buffered the reciprocal relationship between WFC and depression, showing a protective effect in both pathways. These moderation effects were found in the mining industry only suggesting a proximity component moderates the social support buffer hypothesis (i.e., a three way interaction effect). The present paper integrates previous theoretical perspectives of stress and support, and provides insight into the changing dynamics of workplace relationships. PMID:27043592

Small instrument to volcanic seismic signals

NASA Astrophysics Data System (ADS)

Carreras, Normandino; Gomariz, Spartacus; Manuel, Antoni

2014-05-01

Currently, the presence of volcanoes represents a threat to their local populations, and for this reason, scientific communities invest resources to monitor seismic activity of an area, and to obtain information to identify risk situations. To perform such monitoring, it can use different general purpose acquisition systems commercially available, but these devices do not meet to the specifications of reduced dimensions, low weight, low power consumption and low cost. These features allow the system works in autonomous mode for a long period of time, and it makes easy to be carried and to be installed. In the line of designing a volcanic acquisition system with the previously mentioned specifications, exists the Volcanology Department of CSIC, developers of a system with some of these specifications. The objective of this work is to improve the energy consumption requirements of the previous system, providing three channels of data acquisition and with the possibility to transmit data acquisition via radio frequency to a base station, allowing operation it in remote mode. The developed acquisition system consists of three very low-power acquisition modules of Texas Instruments (ADS1246), and this is designed to capture information of the three coordinate axes. A microprocessor also of Texas Instruments (MSP430F5438) is used to work in low-power, due to it is ready to run this consumption and also takes advantage the power save mode in certain moments when system is not working. This system is configurable by serial port, and it has a SD memory to storage data. Contrast to the previous system, it has a RF communication module incorporated specially to work in remote mode of Lynx (YLX-TRM8053-025-05), and boasts also with a GPS module which keeps the time reference synchronized with module of SANAV (GM-1315LA). Thanks to this last selection of components, it is designed a small system about 106 x 106 mm. Assuming that the power supply system is working during all the time, except GPS (it works the 1.4% of time) and the RF communications (it works the 20% of time), it has been able to obtain experimental consumption data of prototype developed. That is the reason why the final power supply of system with one channel active is of 110,5mW when using the communication module. If it calculates the power supply without communication, this consumes about 71mW. The new system needs to work at 3.3V, and the calculations have made in base of that. In contrast, the previous system needs 12V, and does not use RF communications. In order to compare those two versions, is used the power supply as reference, up to 696mW in this previous system. Finally it can be concluded that the implemented electronic design has up to three channels to acquire seismic data, it has the ability to transmit these data by radio frequency to a base station, and power consumption is lower than the initial prototype. The experimental results allow providing an operating time of a year, with weight of 4,84 Kg if the equipment used li-ion batteries.

Inferring individual-level processes from population-level patterns in cultural evolution.

PubMed

Kandler, Anne; Wilder, Bryan; Fortunato, Laura

2017-09-01

Our species is characterized by a great degree of cultural variation, both within and between populations. Understanding how group-level patterns of culture emerge from individual-level behaviour is a long-standing question in the biological and social sciences. We develop a simulation model capturing demographic and cultural dynamics relevant to human cultural evolution, focusing on the interface between population-level patterns and individual-level processes. The model tracks the distribution of variants of cultural traits across individuals in a population over time, conditioned on different pathways for the transmission of information between individuals. From these data, we obtain theoretical expectations for a range of statistics commonly used to capture population-level characteristics (e.g. the degree of cultural diversity). Consistent with previous theoretical work, our results show that the patterns observed at the level of groups are rooted in the interplay between the transmission pathways and the age structure of the population. We also explore whether, and under what conditions, the different pathways can be distinguished based on their group-level signatures, in an effort to establish theoretical limits to inference. Our results show that the temporal dynamic of cultural change over time retains a stronger signature than the cultural composition of the population at a specific point in time. Overall, the results suggest a shift in focus from identifying the one individual-level process that likely produced the observed data to excluding those that likely did not. We conclude by discussing the implications for empirical studies of human cultural evolution.

Differential proteomic responses of selectively bred and wild-type Sydney rock oyster populations exposed to elevated CO2.

PubMed

Thompson, E L; O'Connor, W; Parker, L; Ross, P; Raftos, D A

2015-03-01

Previous work suggests that larvae from Sydney rock oysters that have been selectively bred for fast growth and disease resistance are more resilient to the impacts of ocean acidification than nonselected, wild-type oysters. In this study, we used proteomics to investigate the molecular differences between oyster populations in adult Sydney rock oysters and to identify whether these form the basis for observations seen in larvae. Adult oysters from a selective breeding line (B2) and nonselected wild types (WT) were exposed for 4 weeks to elevated pCO2 (856 μatm) before their proteomes were compared to those of oysters held under ambient conditions (375 μatm pCO2 ). Exposure to elevated pCO2 resulted in substantial changes in the proteomes of oysters from both the selectively bred and wild-type populations. When biological functions were assigned, these differential proteins fell into five broad, potentially interrelated categories of subcellular functions, in both oyster populations. These functional categories were energy production, cellular stress responses, the cytoskeleton, protein synthesis and cell signalling. In the wild-type population, proteins were predominantly upregulated. However, unexpectedly, these cellular systems were downregulated in the selectively bred oyster population, indicating cellular dysfunction. We argue that this reflects a trade-off, whereby an adaptive capacity for enhanced mitochondrial energy production in the selectively bred population may help to protect larvae from the effects of elevated CO2 , whilst being deleterious to adult oysters. © 2015 John Wiley & Sons Ltd.

Sexual revictimization among Iraq and Afghanistan war era veterans.

PubMed

Schry, Amie R; Beckham, Jean C; The Va Mid-Atlantic Mirecc Workgroup; Calhoun, Patrick S

2016-06-30

Research in both civilian and military populations has demonstrated that females who experience childhood sexual abuse (CSA) are more likely to experience sexual assault in adulthood than females who did not experience CSA. Among veteran samples, however, little research has examined previous sexual assault as a risk factor of military sexual assault and post-military sexual assault, and very little research has examined revictimization in male veterans. The purpose of this study was to examine risk of sexual revictimization in a sample of veterans who served during the wars in Iraq and Afghanistan. A sample of 3106 veterans (80.4% male) completed a measure of lifetime exposure to traumatic events, including sexual abuse and sexual assault. Logistic regression analyses were used to examine previous sexual abuse/assault as predictors of later sexual assault; analyses were conducted separately for males and females. In general, previous sexual abuse/assault was associated with later sexual assault in both male and female veterans. These findings have important assessment and treatment implications for clinicians working with veterans. Published by Elsevier Ireland Ltd.

Genetic Structure of Pacific Trout at the Extreme Southern End of Their Native Range

PubMed Central

Abadía-Cardoso, Alicia; Garza, John Carlos; Mayden, Richard L.; García de León, Francisco Javier

2015-01-01

Salmonid fishes are cold water piscivores with a native distribution spanning nearly the entire temperate and subarctic northern hemisphere. Trout in the genus Oncorhynchus are the most widespread salmonid fishes and are among the most important fish species in the world, due to their extensive use in aquaculture and valuable fisheries. Trout that inhabit northwestern Mexico are the southernmost native salmonid populations in the world, and the least studied in North America. They are unfortunately also facing threats to their continued existence. Previous work has described one endemic species, the Mexican golden trout (O. chrysogaster), and one endemic subspecies, Nelson’s trout (O. mykiss nelsoni), in Mexico, but previous work indicated that there is vastly more biodiversity in this group than formally described. Here we conducted a comprehensive genetic analysis of this important group of fishes using novel genetic markers and techniques to elucidate the biodiversity of trout inhabiting northwestern Mexico, examine genetic population structure of Mexican trout and their relationships to other species of Pacific trout, and measure introgression from non-native hatchery rainbow trout. We confirmed substantial genetic diversity and extremely strong genetic differentiation present in the Mexican trout complex, not only between basins but also between some locations within basins, with at least four species-level taxa present. We also revealed significant divergence between Mexican trout and other trout species and found that introgression from non-native rainbow trout is present but limited, and that the genetic integrity of native trout is still maintained in most locations. This information will help to guide effective conservation strategies for this important group of fishes. PMID:26509445

Sick leave during pregnancy: a longitudinal study of rates and risk factors in a Norwegian population.

PubMed

Dørheim, S K; Bjorvatn, B; Eberhard-Gran, M

2013-04-01

To describe the prevalence of, reasons given for, and factors associated with sick leave during pregnancy. Longitudinal, population-based descriptive study. Akershus University Hospital, Norway. All women scheduled to give birth at the hospital (November 2008 to April 2010). Consenting women were handed a questionnaire at the routine ultrasound check at 17 weeks of gestation. Women returning this questionnaire received a second questionnaire at 32 weeks of gestation. Multiple logistic regression analyses were performed to examine associations with somatic, psychiatric and social factors. Rates and duration of sick leave. By 32 weeks of gestation, 63.2% of the 2918 women included were on sick leave, and 75.3% had been on sick leave at some point during their pregnancy. Pelvic girdle pain and fatigue/sleep problems were the main reasons given for sick leave. Being on sick leave in all trimesters was strongly associated with hyperemesis, exercising less than weekly, chronic pain before or during pregnancy, infertility treatment (all P < 0.001); younger maternal age, conflicts in the workplace (both P < 0.01); multiparity, previous depression, insomnia and lower education (all P < 0.05). Sick leave was associated with elective caesarean section and higher infant birthweight (P < 0.01). Adjustment of the work situation was associated with 1 week shorter duration of sick leave. Most women receive sick leave during pregnancy, but sick leave might not be caused by pregnancy alone. Previous medical and psychiatric history, work conditions and socio-economic factors need to be addressed to understand sick leave during pregnancy. © 2012 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2012 RCOG.

HST/ACS Observations of RR Lyrae Stars in Six Ultra-Deep Fields of M31

NASA Technical Reports Server (NTRS)

Jeffery, E. J.; Smith, E.; Brown, T. M.; Sweigart, A. V.; Kalirai, J. S.; Ferguson, H. C.; Guhathakurta, P.; Renzini, A.; Rich, R. M.

2010-01-01

We present HST/ACS observations of RR Lyrae variable stars in six ultra deep fields of the Andromeda galaxy (M31), including parts of the halo, disk, and giant stellar stream. Past work on the RR Lyrae stars in M31 has focused on various aspects of the stellar populations that make up the galaxy s halo, including their distances and metallicities. This study builds upon this previous work by increasing the spatial coverage (something that has been lacking in previous studies) and by searching for these variable stars in constituents of the galaxy not yet explored. Besides the 55 RR Lyrae stars we found in our initial field located 11kpc from the galactic nucleus, we find additional RR Lyrae stars in four of the remaining five ultra deep fields as follows: 21 in the disk, 24 in the giant stellar stream, 3 in the halo field 21kpc from the galactic nucleus, and 5 in one of the halo fields at 35kpc. No RR Lyrae were found in the second halo field at 35kpc. The RR Lyrae populations of these fields appear to mostly be of Oosterhoff I type, although the 11kpc field appears to be intermediate or mixed. We will discuss the properties of these stars including period and reddening distributions. We calculate metallicities and distances for the stars in each of these fields using different methods and compare the results, to an extent that has not yet been done. We compare these methods not just on RR Lyrae in our M31 fields, but also on a data set of Milky Way field RR Lyrae stars.

Physiological differences between female limited, alternative life history strategies: The Alba phenotype in the butterfly Colias croceus.

PubMed

Woronik, Alyssa; Stefanescu, Constanti; Käkelä, Reijo; Wheat, Christopher W; Lehmann, Philipp

Across a wide range of taxa, individuals within populations exhibit alternative life history strategies (ALHS) where their phenotypes dramatically differ due to divergent investments in growth, reproduction and survivorship, with the resulting trade-offs directly impacting Darwinian fitness. Though the maintenance of ALHS within populations is fairly well understood, little is known regarding the physiological mechanisms that underlie ALHS and how environmental conditions can affect the evolution and expression of these phenotypes. One such ALHS, known as Alba, exists within females of many species in the butterfly genus Colias. Previous works in New World species not only found that female morphs differ in their wing color due to a reallocation of resources away from the synthesis of wing pigments to other areas of development, but also that temperature played an important role in these trade-offs. Here we build on previous work conducted in New World species by measuring life history traits and conducting lipidomics on individuals reared at hot and cold temperatures in the Old World species Colias croceus. Results suggest that the fitness of Alba and orange morphs likely varies with rearing temperature, where Alba females have higher fitness in cold conditions and orange in warm. Additionally shared traits between Old and New World species suggest the Alba mechanism is likely conserved across the genus. Finally, in the cold treatment we observe an intermediate yellow morph that may have decreased fitness due to slower larval development. This cost may manifest as disruptive selection in the field, thereby favoring the maintenance of the two discrete morphs. Taken together these results add insights into the evolution of, and the selection on, the Alba ALHS. Copyright © 2018 Elsevier Ltd. All rights reserved.

First Results of Modeling Radiation Belt Electron Dynamics with the SAMI3 Plasmasphere Model

NASA Astrophysics Data System (ADS)

Komar, C. M.; Glocer, A.; Huba, J.; Fok, M. C. H.; Kang, S. B.; Buzulukova, N.

2017-12-01

The radiation belts were one of the first discoveries of the Space Age some sixty years ago and radiation belt models have been improving since the discovery of the radiation belts. The plasmasphere is one region that has been critically important to determining the dynamics of radiation belt populations. This region of space plays a critical role in describing the distribution of chorus and magnetospheric hiss waves throughout the inner magnetosphere. Both of these waves have been shown to interact with energetic electrons in the radiation belts and can result in the energization or loss of radiation belt electrons. However, radiation belt models have been historically limited in describing the distribution of cold plasmaspheric plasma and have relied on empirically determined plasmasphere models. Some plasmasphere models use an azimuthally symmetric distribution of the plasmasphere which can fail to capture important plasmaspheric dynamics such as the development of plasmaspheric drainage plumes. Previous work have coupled the kinetic bounce-averaged Comprehensive Inner Magnetosphere-Ionosphere (CIMI) model used to model ring current and radiation belt populations with the Block-adaptive Tree Solar wind Roe-type Upwind Scheme (BATSRUS) global magnetohydrodynamic model to self-consistently obtain the magnetospheric magnetic field and ionospheric potential. The present work will utilize this previous coupling and will additionally couple the SAMI3 plasmasphere model to better represent the dynamics on the plasmasphere and its role in determining the distribution of waves throughout the inner magnetosphere. First results on the relevance of chorus, hiss, and ultralow frequency waves on radiation belt electron dynamics will be discussed in context of the June 1st, 2013 storm-time dropout event.

School-to-work program participation and the post-high school employment of young adults with disabilities

PubMed Central

Shandra, Carrie L.; Hogan, Dennis P.

2014-01-01

Previous research on the education-to-employment transition for students with disabilities has suggested that participation in school-to-work programs is positively associated with post-high school success. This article utilizes data from the National Longitudinal Survey of Youth 1997 (NLSY97) to extend these findings in several ways. First, we assess the efficacy of specific types of school-based and work-based initiatives, including job shadowing, mentoring, cooperative education, school-sponsored enterprise, technical preparation, internships, and career major. Next, we extend the usual focus on the employment outcomes of work status and financial compensation to consider job-specific information on the receipt of fringe benefits. Overall, results from longitudinal multivariate analyses suggest that transition initiatives are effective in facilitating vocational success for this population; however, different aspects of school-to-work programs are beneficial for different aspects of employment. School-based programs are positively associated with stable employment and full-time work while work-based programs most consistently increase the likelihood that youth with disabilities will be employed in jobs that provide fringe benefits. Analyses also indicate that – once individuals with disabilities are stably employed – they can be employed in “good” jobs that provide employee benefits. PMID:25309111

Evaluation of MOSFET-type glucose sensor using platinum electrode with glucose oxidase

NASA Astrophysics Data System (ADS)

Ooe, Katsutoshi; Hamamoto, Yasutaro; Hirano, Yoshiaki

2005-02-01

As the population ages, health management will be one of the important issues. The development of a safe medical machine based on MEMS technologies for the human body will be the primary research project in the future. We have developed the glucose sensor, as one of the medical based devices, for use in the Health Monitoring System (HMS). HMS is the device that continuously monitors human health conditions. For example, blood is the monitoring target of HMS. The glucose sensor specifically detects the glucose levels of the blood and monitors the glucose concentration as the blood sugar level. This glucose sensor has a "separated Au electrode", which immobilizes GOx. In our previous work, GOx was immobilized onto Au electrode by the SAMs (Self-Assembled Monolayer) method, and the sensor, using this working electrode, detected the glucose concentration of an aqueous glucose solution. In this report, we used a Pt electrode, which immobilized GOx, as a working electrode. Au electrode, which was used previously, was dissolved by the application of current in the presence of chloride ions. Based on the above-mentioned fact, a new working electrode, which immobilized GOx, was produced using Pt, which did not possess such characteristics. These Pt working electrodes were produced using the covalent binding method and the cross-link method, and both the electrodes displayed a good sensing property. In addition, the electrode using glutaraldehyde (GA) and bovine serum albumin (BSA) as crosslinking agents was produced, and it displayed better characteristics as compared with those displayed by the electrode that used only GA. Based on the above-mentioned techniques, the improvement in performance of the sensor was confirmed.

Wilms Tumor NCAM-Expressing Cancer Stem Cells as Potential Therapeutic Target for Polymeric Nanomedicine.

PubMed

Markovsky, Ela; Vax, Einav; Ben-Shushan, Dikla; Eldar-Boock, Anat; Shukrun, Rachel; Yeini, Eilam; Barshack, Iris; Caspi, Revital; Harari-Steinberg, Orit; Pode-Shakked, Naomi; Dekel, Benjamin; Satchi-Fainaro, Ronit

2017-11-01

Cancer stem cells (CSC) form a specific population within the tumor that has been shown to have self-renewal and differentiation properties, increased ability to migrate and form metastases, and increased resistance to chemotherapy. Consequently, even a small number of cells remaining after therapy can repopulate the tumor and cause recurrence of the disease. CSCs in Wilms tumor, a pediatric renal cancer, were previously shown to be characterized by neural cell adhesion molecule (NCAM) expression. Therefore, NCAM provides a specific biomarker through which the CSC population in this tumor can be targeted. We have recently developed an NCAM-targeted nanosized conjugate of paclitaxel bound to a biodegradable polyglutamic acid polymer. In this work, we examined the ability of the conjugate to inhibit Wilms tumor by targeting the NCAM-expressing CSCs. Results show that the conjugate selectively depleted the CSC population of the tumors and effectively inhibited tumor growth without causing toxicity. We propose that the NCAM-targeted conjugate could be an effective therapeutic for Wilms tumor. Mol Cancer Ther; 16(11); 2462-72. ©2017 AACR . ©2017 American Association for Cancer Research.

Linking extreme interannual changes in prey availability to foraging behaviour and breeding investment in a marine predator, the macaroni penguin.

PubMed

Horswill, Cat; Trathan, Philip N; Ratcliffe, Norman

2017-01-01

Understanding the mechanisms that link prey availability to predator behaviour and population change is central to projecting how a species may respond to future environmental pressures. We documented the behavioural responses and breeding investment of macaroni penguins Eudyptes chrysolophus across five breeding seasons where local prey density changed by five-fold; from very low to highly abundant. When prey availability was low, foraging trips were significantly longer and extended overnight. Birds also foraged farther from the colony, potentially in order to reach more distant foraging grounds and allow for increased search times. These extended foraging trips were also linked to a marked decrease in fledgling weights, most likely associated with reduced rates of provisioning. Furthermore, by comparing our results with previous work on this population, it appears that lowered first-year survival rates associated, at least partially, with fledging masses were also evident for this cohort. This study integrates a unique set of prey density, predator behaviour and predator breeding investment data to highlight a possible behavioural mechanism linking perturbations in prey availability to population demography.

Population Accessibility to Radiotherapy Services in New South Wales Region of Australia: a methodological contribution

NASA Astrophysics Data System (ADS)

Shukla, Nagesh; Wickramasuriya, Rohan; Miller, Andrew; Perez, Pascal

2015-05-01

This paper proposes an integrated modelling process to assess the population accessibility to radiotherapy treatment services in future based on future cancer incidence and road network-based accessibility. Previous research efforts assessed travel distance/time barriers affecting access to cancer treatment services, as well as epidemiological studies that showed that cancer incidence rates vary with population demography. It is established that travel distances to treatment centres and demographic profiles of the accessible regions greatly influence the demand for cancer radiotherapy (RT) services. However, an integrated service planning approach that combines spatially-explicit cancer incidence projections, and the RT services accessibility based on patient road network have never been attempted. This research work presents this novel methodology for the accessibility assessment of RT services and demonstrates its viability by modelling New South Wales (NSW) cancer incidence rates for different age-sex groups based on observed cancer incidence trends; estimating the road network-based access to current NSW treatment centres; and, projecting the demand for RT services in New South Wales, Australia from year 2011 to 2026.

Effects of axions on Population III stars

NASA Astrophysics Data System (ADS)

Choplin, Arthur; Coc, Alain; Meynet, Georges; Olive, Keith A.; Uzan, Jean-Philippe; Vangioni, Elisabeth

2017-09-01

Aims: Following the renewed interest in axions as a dark matter component, we revisit the effects of energy loss by axion emission on the evolution of the first generation of stars. These stars with zero metallicity are assumed to be massive, more compact, and hotter than subsequent generations. It is hence important to extend previous studies, which were restricted to solar metallicity stars. Methods: Our analysis first compares the evolution of solar metallicity 8, 10, and 12 M⊙ stars to previous work. We then calculate the evolution of 8 zero-metallicity stars with and without axion losses and with masses ranging from 20 to 150 M⊙. Results: For the solar metallicity models, we confirm the disappearance of the blue-loop phase for a value of the axion-photon coupling of gaγ = 10-10 GeV-1. We show that for gaγ = 10-10 GeV-1, the evolution of Population III stars is not much affected by axion losses, except within the range of masses 80-130 M⊙. Such stars show significant differences in both their tracks within the Tc-ρc diagram and their central composition (in particular 20Ne and 24Mg). We discuss the origin of these modifications from the stellar physics point of view, and also their potential observational signatures.

Cortical circuitry implementing graphical models.

PubMed

Litvak, Shai; Ullman, Shimon

2009-11-01

In this letter, we develop and simulate a large-scale network of spiking neurons that approximates the inference computations performed by graphical models. Unlike previous related schemes, which used sum and product operations in either the log or linear domains, the current model uses an inference scheme based on the sum and maximization operations in the log domain. Simulations show that using these operations, a large-scale circuit, which combines populations of spiking neurons as basic building blocks, is capable of finding close approximations to the full mathematical computations performed by graphical models within a few hundred milliseconds. The circuit is general in the sense that it can be wired for any graph structure, it supports multistate variables, and it uses standard leaky integrate-and-fire neuronal units. Following previous work, which proposed relations between graphical models and the large-scale cortical anatomy, we focus on the cortical microcircuitry and propose how anatomical and physiological aspects of the local circuitry may map onto elements of the graphical model implementation. We discuss in particular the roles of three major types of inhibitory neurons (small fast-spiking basket cells, large layer 2/3 basket cells, and double-bouquet neurons), subpopulations of strongly interconnected neurons with their unique connectivity patterns in different cortical layers, and the possible role of minicolumns in the realization of the population-based maximum operation.

Prevalence and incidence of Entamoeba histolytica infection in South Africa and Egypt.

PubMed

Stauffer, William; Abd-Alla, Mohamed; Ravdin, Jonathan I

2006-02-01

There are little data on the true prevalence and incidence of Entamoeba histolytica infection in Africa. This is due to the inability, historically, to differentiate Entamoeba histolytica from the more common, but non-pathogenic, Entamoeba dispar. In addition, newer studies have demonstrated that the previous gold standard, culture with zymodeme analysis, is insensitive in detecting the presence of infection, especially when compared to PCR. Recent published articles as well as data from the authors' previous work are reviewed and summarized to elucidate what is known about prevalence and incidence of Entamoeba histolytica in Africa. The majority of data on asymptomatic infection are published from South Africa, Egypt and Cote d'Ivoire. Egypt has high rates of asymptomatic infection detected in the stool (>21%), whereas South Africa and Cote d'Ivoire rates range between 0 and 2%. Seroprevalence estimates the rate of recent infection, because anti-amebic antibodies generally persist for <5 years. Seropositivity rates (IgG, IgA) range from approximately 10 to 20%, indicating recent infection in this proportion of the population. Entamoeba histolytica infects a significant proportion of many populations of Africa; however, little data are currently available to indicate true prevalence and incidence. Further studies are needed to determine the burden of infection and disease in Africa.

Marker-Based Estimates Reveal Significant Non-additive Effects in Clonally Propagated Cassava (Manihot esculenta): Implications for the Prediction of Total Genetic Value and the Selection of Varieties.

PubMed

Wolfe, Marnin D; Kulakow, Peter; Rabbi, Ismail Y; Jannink, Jean-Luc

2016-08-31

In clonally propagated crops, non-additive genetic effects can be effectively exploited by the identification of superior genetic individuals as varieties. Cassava (Manihot esculenta Crantz) is a clonally propagated staple food crop that feeds hundreds of millions. We quantified the amount and nature of non-additive genetic variation for three key traits in a breeding population of cassava from sub-Saharan Africa using additive and non-additive genome-wide marker-based relationship matrices. We then assessed the accuracy of genomic prediction for total (additive plus non-additive) genetic value. We confirmed previous findings based on diallel populations, that non-additive genetic variation is significant for key cassava traits. Specifically, we found that dominance is particularly important for root yield and epistasis contributes strongly to variation in CMD resistance. Further, we showed that total genetic value predicted observed phenotypes more accurately than additive only models for root yield but not for dry matter content, which is mostly additive or for CMD resistance, which has high narrow-sense heritability. We address the implication of these results for cassava breeding and put our work in the context of previous results in cassava, and other plant and animal species. Copyright © 2016 Author et al.

Violence Against Women in Selected Areas of the United States.

PubMed

Montgomery, Brooke E E; Rompalo, Anne; Hughes, James; Wang, Jing; Haley, Danielle; Soto-Torres, Lydia; Chege, Wairimu; Justman, Jessica; Kuo, Irene; Golin, Carol; Frew, Paula; Mannheimer, Sharon; Hodder, Sally

2015-10-01

We determined the prevalence of recent emotional, physical, and sexual violence against women and their associations with HIV-related risk factors in women living in the United States. We performed an assessment of women ages 18 to 44 years with a history of unprotected sex and 1 or more personal or partner HIV risk factors in the past 6 months from 2009 to 2010. We used multivariable logistic regression to examine the association of experiencing violence. Among 2099 women, the prevalence of emotional abuse, physical violence, and sexual violence in the previous 6 months was 31%, 19%, and 7%, respectively. Nonmarried status, food insecurity, childhood abuse, depression symptomology, and posttraumatic stress disorder were significantly associated with multiple types of violence. All types of violence were associated with at least 3 different partner or personal HIV risk behaviors, including unprotected anal sex, previous sexually transmitted infection diagnosis, sex work, or partner substance abuse. Our data suggested that personal and partner HIV risk behaviors, mental illness, and specific forms of violence frequently co-occurred in the lives of impoverished women. We shed light on factors purported to contribute to a syndemic in this population. HIV prevention programs in similar populations should address these co-occurring issues in a comprehensive manner.

Violence Against Women in Selected Areas of the United States

PubMed Central

Rompalo, Anne; Hughes, James; Wang, Jing; Haley, Danielle; Soto-Torres, Lydia; Chege, Wairimu; Justman, Jessica; Kuo, Irene; Golin, Carol; Frew, Paula; Mannheimer, Sharon; Hodder, Sally

2015-01-01

Objectives. We determined the prevalence of recent emotional, physical, and sexual violence against women and their associations with HIV-related risk factors in women living in the United States. Methods. We performed an assessment of women ages 18 to 44 years with a history of unprotected sex and 1 or more personal or partner HIV risk factors in the past 6 months from 2009 to 2010. We used multivariable logistic regression to examine the association of experiencing violence. Results. Among 2099 women, the prevalence of emotional abuse, physical violence, and sexual violence in the previous 6 months was 31%, 19%, and 7%, respectively. Nonmarried status, food insecurity, childhood abuse, depression symptomology, and posttraumatic stress disorder were significantly associated with multiple types of violence. All types of violence were associated with at least 3 different partner or personal HIV risk behaviors, including unprotected anal sex, previous sexually transmitted infection diagnosis, sex work, or partner substance abuse. Conclusions. Our data suggested that personal and partner HIV risk behaviors, mental illness, and specific forms of violence frequently co-occurred in the lives of impoverished women. We shed light on factors purported to contribute to a syndemic in this population. HIV prevention programs in similar populations should address these co-occurring issues in a comprehensive manner. PMID:25790408

Efficient probabilistic inference in generic neural networks trained with non-probabilistic feedback.

PubMed

Orhan, A Emin; Ma, Wei Ji

2017-07-26

Animals perform near-optimal probabilistic inference in a wide range of psychophysical tasks. Probabilistic inference requires trial-to-trial representation of the uncertainties associated with task variables and subsequent use of this representation. Previous work has implemented such computations using neural networks with hand-crafted and task-dependent operations. We show that generic neural networks trained with a simple error-based learning rule perform near-optimal probabilistic inference in nine common psychophysical tasks. In a probabilistic categorization task, error-based learning in a generic network simultaneously explains a monkey's learning curve and the evolution of qualitative aspects of its choice behavior. In all tasks, the number of neurons required for a given level of performance grows sublinearly with the input population size, a substantial improvement on previous implementations of probabilistic inference. The trained networks develop a novel sparsity-based probabilistic population code. Our results suggest that probabilistic inference emerges naturally in generic neural networks trained with error-based learning rules.Behavioural tasks often require probability distributions to be inferred about task specific variables. Here, the authors demonstrate that generic neural networks can be trained using a simple error-based learning rule to perform such probabilistic computations efficiently without any need for task specific operations.

Epidemiological tracking and population assignment of the non-clonal bacterium, Burkholderia pseudomallei.

PubMed

Dale, Julia; Price, Erin P; Hornstra, Heidie; Busch, Joseph D; Mayo, Mark; Godoy, Daniel; Wuthiekanun, Vanaporn; Baker, Anthony; Foster, Jeffrey T; Wagner, David M; Tuanyok, Apichai; Warner, Jeffrey; Spratt, Brian G; Peacock, Sharon J; Currie, Bart J; Keim, Paul; Pearson, Talima

2011-12-01

Rapid assignment of bacterial pathogens into predefined populations is an important first step for epidemiological tracking. For clonal species, a single allele can theoretically define a population. For non-clonal species such as Burkholderia pseudomallei, however, shared allelic states between distantly related isolates make it more difficult to identify population defining characteristics. Two distinct B. pseudomallei populations have been previously identified using multilocus sequence typing (MLST). These populations correlate with the major foci of endemicity (Australia and Southeast Asia). Here, we use multiple Bayesian approaches to evaluate the compositional robustness of these populations, and provide assignment results for MLST sequence types (STs). Our goal was to provide a reference for assigning STs to an established population without the need for further computational analyses. We also provide allele frequency results for each population to enable estimation of population assignment even when novel STs are discovered. The ability for humans and potentially contaminated goods to move rapidly across the globe complicates the task of identifying the source of an infection or outbreak. Population genetic dynamics of B. pseudomallei are particularly complicated relative to other bacterial pathogens, but the work here provides the ability for broad scale population assignment. As there is currently no independent empirical measure of successful population assignment, we provide comprehensive analytical details of our comparisons to enable the reader to evaluate the robustness of population designations and assignments as they pertain to individual research questions. Finer scale subdivision and verification of current population compositions will likely be possible with genotyping data that more comprehensively samples the genome. The approach used here may be valuable for other non-clonal pathogens that lack simple group-defining genetic characteristics and provides a rapid reference for epidemiologists wishing to track the origin of infection without the need to compile population data and learn population assignment algorithms.

Acoustic neuroma: potential risk factors and audiometric surveillance in the aluminium industry.

PubMed

Taiwo, Oyebode; Galusha, Deron; Tessier-Sherman, Baylah; Kirsche, Sharon; Cantley, Linda; Slade, Martin D; Cullen, Mark R; Donoghue, A Michael

2014-09-01

To look for an association between acoustic neuroma (AN) and participation in a hearing conservation programme (HCP) and also for an association between AN and possible occupational risk factors in the aluminium industry. We conducted a case-control analysis of a population of US aluminium production workers in 8 smelters and 43 other plants. Using insurance claims data, 97 cases of AN were identified between 1996 and 2009. Each was matched with four controls. Covariates included participation in a HCP, working in an aluminium smelter, working in an electrical job and hearing loss. In the bivariate analyses, covariates associated with AN were participation in the HCP (OR=1.72; 95% CI 1.09 to 2.69) and smelter work (OR=1.88; 95% CI 1.06 to 3.36). Electrical work was not significant (OR=1.60; 95% CI 0.65 to 3.94). Owing to high participation in the HCP in smelters, multivariate subanalyses were required. In the multivariate analyses, participation in the HCP was the only statistically significant risk factor for AN. In the multivariate analysis restricted to employees not working in a smelter, the OR was 1.81 (95% CI 1.04 to 3.17). Hearing loss, an indirect measure of in-ear noise dose, was not predictive of AN. Our results suggest the incidental detection of previously undiagnosed tumours in workers who participated in the company-sponsored HCP. The increased medical surveillance among this population of workers most likely introduced detection bias, leading to the identification of AN cases that would have otherwise remained undetected. 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.

Genetic composition and connectivity of the Antillean manatee (Trichechus manatus manatus) in Panama

USGS Publications Warehouse

Díaz-Ferguson, Edgardo; Hunter, Margaret; Guzmán, Héctor M.

2017-01-01

Genetic diversity and haplotype composition of the West Indian manatee (Trichechus manatus) population from the San San Pond Sak wetland in Bocas del Toro, Panama was studied using a segment of mitochondrial DNA (D’loop). No genetic information has been published to date for Panamanian populations. Due to the secretive behavior and small population size of the species in the area, DNA extraction was conducted from opportunistically collected fecal (N=20), carcass tissue (N=4) and bone (N=4) samples. However, after DNA processing only 10 samples provided good quality DNA for sequencing (3 fecal, 4 tissue and 3 bone samples). We found three haplotypes in total; two of these haplotypes are reported for the first time, J02 (N=3) and J03 (N=4), and one J01 was previously published (N=3). Genetic diversity showed similar values to previous studies conducted in other Caribbean regions with moderate values of nucleotide diversity (π= 0.00152) and haplotipic diversity (Hd= 0.57). Connectivity assessment was based on sequence similarity, genetic distance and genetic differentiation between San San population and other manatee populations previously studied. The J01 haplotype found in the Panamanian population is shared with populations in the Caribbean mainland and the Gulf of Mexico showing a reduced differentiation corroborated with Fst value between HSSPS and this region of 0.0094. In contrast, comparisons between our sequences and populations in the Eastern Caribbean (South American populations) and North Western Caribbean showed fewer similarities (Fst =0.049 and 0.058, respectively). These results corroborate previous phylogeographic patterns already established for manatee populations and situate Panamanian populations into the Belize and Mexico cluster. In addition, these findings will be a baseline for future studies and comparisons with manatees in other areas of Panama and Central America. These results should be considered to inform management decisions regarding conservation of genetic diversity, future controlled introductions, connectivity and effective population size of the West Indian manatee along the Central American corridor.

Productivity Losses Associated with Head and Neck Cancer Using the Human Capital and Friction Cost Approaches.

PubMed

Pearce, Alison M; Hanly, Paul; Timmons, Aileen; Walsh, Paul M; O'Neill, Ciaran; O'Sullivan, Eleanor; Gooberman-Hill, Rachael; Thomas, Audrey Alforque; Gallagher, Pamela; Sharp, Linda

2015-08-01

Previous studies suggest that productivity losses associated with head and neck cancer (HNC) are higher than in other cancers. These studies have only assessed a single aspect of productivity loss, such as temporary absenteeism or premature mortality, and have only used the Human Capital Approach (HCA). The Friction Cost Approach (FCA) is increasingly recommended, although has not previously been used to assess lost production from HNC. The aim of this study was to estimate the lost productivity associated with HNC due to different types of absenteeism and premature mortality, using both the HCA and FCA. Survey data on employment status were collected from 251 HNC survivors in Ireland and combined with population-level survival estimates and national wage data. The cost of temporary and permanent time off work, reduced working hours and premature mortality using both the HCA and FCA were calculated. Estimated total productivity losses per employed person of working age were EUR253,800 using HCA and EUR6800 using FCA. The main driver of HCA costs was premature mortality (38% of total) while for FCA it was temporary time off (73% of total). The productivity losses associated with head and neck cancer are substantial, and return to work assistance could form an important part of rehabilitation. Use of both the HCA and FCA approaches allowed different drivers of productivity losses to be identified, due to the different assumptions of the two methods. For future estimates of productivity losses, the use of both approaches may be pragmatic.

Beta decay of the fission product 125Sb and a new complete evaluation of absolute gamma ray transition intensities

NASA Astrophysics Data System (ADS)

Rajput, M. U.; Ali, N.; Hussain, S.; Mujahid, S. A.; MacMahon, D.

2012-04-01

The radionuclide 125Sb is a long-lived fission product, which decays to 125Te by negative beta emission with a half-life of 1008 day. The beta decay is followed by the emission of several gamma radiations, ranging from low to medium energy, that can suitably be used for high-resolution detector calibrations, decay heat calculations and in many other applications. In this work, the beta decay of 125Sb has been studied in detail. The complete published experimental data of relative gamma ray intensities in the beta decay of the radionuclide 125Sb has been compiled. The consistency analysis was performed and discrepancies found at several gamma ray energies. Evaluation of the discrepant data was carried out using Normalized Residual and RAJEVAL methods. The decay scheme balance was carried out using beta branching ratios, internal conversion coefficients, populating and depopulating gamma transitions to 125Te levels. The work has resulted in the consistent conversion factor equal to 29.59(13) %, and determined a new evaluated set of the absolute gamma ray emission probabilities. The work has also shown 22.99% of the delayed intensity fraction as outgoing from the 58 d isomeric 144 keV energy level and 77.01% of the prompt intensity fraction reaching to the ground state from the other excited states. The results are discussed and compared with previous evaluations. The present work includes additional experimental data sets which were not included in the previous evaluations. A new set of recommended relative and absolute gamma ray emission probabilities is presented.

Surveillance of work-related asthma in new york state.

PubMed

Tice, Cori J; Cummings, Karen R; Gelberg, Kitty H

2010-04-01

The objective of this paper is to determine the percent of adults with asthma attributable to work and describe characteristics of the work-related asthma population in New York State. Sociodemographic and control characteristics of those with and without work-related asthma are compared. Data from three population-based surveys and one case-based surveillance system were analyzed. Work-relatedness of asthma was determined by self-report for the population-based surveys and by physician report for the case-based system. Self-reported sociodemographic and control characteristics were analyzed for the population-based surveys by work-relatedness. The percent of work-relatedness among adults with current asthma in New York State ranged from 10.6% to 44.5%. Significantly more adults with work-related asthma had poorly controlled asthma than those without work-related asthma. More adults with work-related asthma also tended to be employed in the manufacturing, educational services, and public administration industries than the general population. The most frequently reported exposure was dust. Adults with work-related asthma have decreased control and adverse socioeconomic impacts compared to those with asthma that is not work-related. Increased recognition and physician reporting is necessary to further prevent the impact of work-related exposures.

Passive smoking and its impact on employers and employees in Hong Kong.

PubMed

McGhee, S M; Hedley, A J; Ho, L M

2002-12-01

To estimate the prevalence of passive smoking at work in the whole workforce in Hong Kong (population 6.8 million), the characteristics of the passive smokers, any extra use of health care among passive smokers, and who pays for that health care. A random sample of 14,325 households was contacted by telephone; 6,186 responding adults who worked full time were asked about their employment, their most recent use of health care and the cost of that care, their medical benefits, and their exposure to secondhand smoke in the workplace. After weighting the sample for sex, age, household size, and income, 4,739 subjects were included in the analysis. Of 1,961 full time workers who did not smoke, 47.5% were exposed to secondhand smoke in the workplace compared with only 26% exposed at home. Exposure at work was associated with being younger, male, married, less educated, and having a lower income. Those exposed at work were 37% more likely to report having visited a doctor for a respiratory illness in the previous 14 days. Employers were paying 28% of the cost of these visits, the government paid 8%, and the individuals paid 63%. If extrapolated to the 3 million workers in the Hong Kong population, employers would pay just over US$9 million per year, while the affected workers would pay around US$20 million. As well as the costs of active smoking, the cost of extra health care utilisation associated with passive smoking is an additional cost being paid by those employers who have not established smoke free workplaces and by their employees.

Match probabilities in a finite, subdivided population

PubMed Central

Malaspinas, Anna-Sapfo; Slatkin, Montgomery; Song, Yun S.

2011-01-01

We generalize a recently introduced graphical framework to compute the probability that haplotypes or genotypes of two individuals drawn from a finite, subdivided population match. As in the previous work, we assume an infinite-alleles model. We focus on the case of a population divided into two subpopulations, but the underlying framework can be applied to a general model of population subdivision. We examine the effect of population subdivision on the match probabilities and the accuracy of the product rule which approximates multi-locus match probabilities as a product of one-locus match probabilities. We quantify the deviation from predictions of the product rule by R, the ratio of the multi-locus match probability to the product of the one-locus match probabilities.We carry out the computation for two loci and find that ignoring subdivision can lead to underestimation of the match probabilities if the population under consideration actually has subdivision structure and the individuals originate from the same subpopulation. On the other hand, under a given model of population subdivision, we find that the ratio R for two loci is only slightly greater than 1 for a large range of symmetric and asymmetric migration rates. Keeping in mind that the infinite-alleles model is not the appropriate mutation model for STR loci, we conclude that, for two loci and biologically reasonable parameter values, population subdivision may lead to results that disfavor innocent suspects because of an increase in identity-by-descent in finite populations. On the other hand, for the same range of parameters, population subdivision does not lead to a substantial increase in linkage disequilibrium between loci. Those results are consistent with established practice. PMID:21266180

Embodied conversational agents for multimodal automated social skills training in people with autism spectrum disorders.

PubMed

Tanaka, Hiroki; Negoro, Hideki; Iwasaka, Hidemi; Nakamura, Satoshi

2017-01-01

Social skills training, performed by human trainers, is a well-established method for obtaining appropriate skills in social interaction. Previous work automated the process of social skills training by developing a dialogue system that teaches social communication skills through interaction with a computer avatar. Even though previous work that simulated social skills training only considered acoustic and linguistic information, human social skills trainers take into account visual and other non-verbal features. In this paper, we create and evaluate a social skills training system that closes this gap by considering the audiovisual features of the smiling ratio and the head pose (yaw and pitch). In addition, the previous system was only tested with graduate students; in this paper, we applied our system to children or young adults with autism spectrum disorders. For our experimental evaluation, we recruited 18 members from the general population and 10 people with autism spectrum disorders and gave them our proposed multimodal system to use. An experienced human social skills trainer rated the social skills of the users. We evaluated the system's effectiveness by comparing pre- and post-training scores and identified significant improvement in their social skills using our proposed multimodal system. Computer-based social skills training is useful for people who experience social difficulties. Such a system can be used by teachers, therapists, and social skills trainers for rehabilitation and the supplemental use of human-based training anywhere and anytime.

Embodied conversational agents for multimodal automated social skills training in people with autism spectrum disorders

PubMed Central

Negoro, Hideki; Iwasaka, Hidemi; Nakamura, Satoshi

2017-01-01

Social skills training, performed by human trainers, is a well-established method for obtaining appropriate skills in social interaction. Previous work automated the process of social skills training by developing a dialogue system that teaches social communication skills through interaction with a computer avatar. Even though previous work that simulated social skills training only considered acoustic and linguistic information, human social skills trainers take into account visual and other non-verbal features. In this paper, we create and evaluate a social skills training system that closes this gap by considering the audiovisual features of the smiling ratio and the head pose (yaw and pitch). In addition, the previous system was only tested with graduate students; in this paper, we applied our system to children or young adults with autism spectrum disorders. For our experimental evaluation, we recruited 18 members from the general population and 10 people with autism spectrum disorders and gave them our proposed multimodal system to use. An experienced human social skills trainer rated the social skills of the users. We evaluated the system’s effectiveness by comparing pre- and post-training scores and identified significant improvement in their social skills using our proposed multimodal system. Computer-based social skills training is useful for people who experience social difficulties. Such a system can be used by teachers, therapists, and social skills trainers for rehabilitation and the supplemental use of human-based training anywhere and anytime. PMID:28796781

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

Morrill, J.S.; Benesch, W.M.

Previous model results have shown that the N{sub 2} triplet vibrational level populations in the aurora are strongly affected by cascade and quenching by atomic and molecular oxygen. As the aurora penetrates to lower altitudes (less than 100 km) the role of quenching by atomic oxygen becomes less important and processes involving N{sub 2} collisions begin to play a more prominent part. The authors are developing a model which will yield steady state vibrational level populations for both the singlet and triplet valence states of N{sub 2}. The model currently provides results for the seven low-lying N{sub 2} triplet statesmore » (A {sup 3}{Sigma}{sub u}{sup +}, B {sup 3}{Pi}{sub g}, W {sup 3}{Delta}{sub u}, B{prime}{sup 3}{Sigma}{sub u}, C{sup 3}{Pi}{sub u}, D{sup 3}{Sigma}{sub u}{sup +}, and E{sup 3}{Sigma}{sub g}{sup +}). These states are responsible for auroral emissions from the UV (Vegard-Kaplan (VK), second positive (2PG)) through the visible to the infrared (first positive (1PG), infrared afterglow (IRA), Wu-Benesch (WB)). The authors have included two additional collisional processes in the current model which were not treated previously. These are the intersystem collisional transfer of excitation (ICT) between the B state and the A, W, and B{prime} states and vibrational redistribution within the A state vibrational manifold, both due to collisions with ground state N{sub 2}. The present work compares the current model results with those of a previous model as well as ground, airborne, and rocket observations. The comparison between N{sub 2}(A) (VK) and N{sub 2}(B) (1PG) vibrational level populations predicted by this model and a number of auroral observations indicate that the current model achieves a significant improvement in the fit between calculation and observation. 81 refs., 12 figs., 2 tabs.« less

Mineralogies and source regions of near-Earth asteroids

NASA Astrophysics Data System (ADS)

Dunn, Tasha L.; Burbine, Thomas H.; Bottke, William F.; Clark, John P.

2013-01-01

Near-Earth Asteroids (NEAs) offer insight into a size range of objects that are not easily observed in the main asteroid belt. Previous studies on the diversity of the NEA population have relied primarily on modeling and statistical analysis to determine asteroid compositions. Olivine and pyroxene, the dominant minerals in most asteroids, have characteristic absorption features in the visible and near-infrared (VISNIR) wavelengths that can be used to determine their compositions and abundances. However, formulas previously used for deriving compositions do not work very well for ordinary chondrite assemblages. Because two-thirds of NEAs have ordinary chondrite-like spectral parameters, it is essential to determine accurate mineralogies. Here we determine the band area ratios and Band I centers of 72 NEAs with visible and near-infrared spectra and use new calibrations to derive the mineralogies 47 of these NEAs with ordinary chondrite-like spectral parameters. Our results indicate that the majority of NEAs have LL-chondrite mineralogies. This is consistent with results from previous studies but continues to be in conflict with the population of recovered ordinary chondrites, of which H chondrites are the most abundant. To look for potential correlations between asteroid size, composition, and source region, we use a dynamical model to determine the most probable source region of each NEA. Model results indicate that NEAs with LL chondrite mineralogies appear to be preferentially derived from the ν6 secular resonance. This supports the hypothesis that the Flora family, which lies near the ν6 resonance, is the source of the LL chondrites. With the exception of basaltic achondrites, NEAs with non-chondrite spectral parameters are slightly less likely to be derived from the ν6 resonance than NEAs with chondrite-like mineralogies. The population of NEAs with H, L, and LL chondrite mineralogies does not appear to be influenced by size, which would suggest that ordinary chondrites are not preferentially sourced from meter-sized objects due to Yarkovsky effect.

Aridity weakens population-level effects of multiple species interactions on Hibiscus meyeri.

PubMed

Louthan, Allison M; Pringle, Robert M; Goheen, Jacob R; Palmer, Todd M; Morris, William F; Doak, Daniel F

2018-01-16

Predicting how species' abundances and ranges will shift in response to climate change requires a mechanistic understanding of how multiple factors interact to limit population growth. Both abiotic stress and species interactions can limit populations and potentially set range boundaries, but we have a poor understanding of when and where each is most critical. A commonly cited hypothesis, first proposed by Darwin, posits that abiotic factors (e.g., temperature, precipitation) are stronger determinants of range boundaries in apparently abiotically stressful areas ("stress" indicates abiotic factors that reduce population growth), including desert, polar, or high-elevation environments, whereas species interactions (e.g., herbivory, competition) play a stronger role in apparently less stressful environments. We tested a core tenet of this hypothesis-that population growth rate is more strongly affected by species interactions in less stressful areas-using experimental manipulations of species interactions affecting a common herbaceous plant, Hibiscus meyeri (Malvaceae), across an aridity gradient in a semiarid African savanna. Population growth was more strongly affected by four distinct species interactions (competition with herbaceous and shrubby neighbors, herbivory, and pollination) in less stressful mesic areas than in more stressful arid sites. However, contrary to common assumptions, this effect did not arise because of greater density or diversity of interacting species in less stressful areas, but rather because aridity reduced sensitivity of population growth to these interactions. Our work supports classic predictions about the relative strength of factors regulating population growth across stress gradients, but suggests that this pattern results from a previously unappreciated mechanism that may apply to many species worldwide.

Alcohol use and its consequences in South India: views from a marginalised tribal population.

PubMed

Mohindra, K S; Narayana, D; Anushreedha, S S; Haddad, Slim

2011-08-01

Alcohol consumption in India is disproportionately higher among poorer and socially marginalised groups, notably Scheduled Tribes (STs). We lack an understanding of STs own views with regard to alcohol, which is important for implementing appropriate interventions. This study was undertaken with the Paniyas (a previously enslaved ST) in a rural community in Kerala, South India. The study, nested in a participatory poverty and health assessment (PPHA). PPHA aims to enable marginalized groups to define, describe, analyze, and express their own perceptions through a combination of qualitative methods and participatory approaches (e.g. participatory mapping and ranking exercises). We worked with 5 Paniya colonies between January and June 2008. Alcohol is viewed as a problem among the Paniyas who reported that consumption is increasing, notably among younger men. Alcohol is easily available in licensed shops and is produced illicitly in some colonies. There is evidence that local employers are using alcohol to attract Paniyas for work. Male alcohol consumption is associated with a range of social and economic consequences that are rooted in historical oppression and social discrimination. Future research should examine the views of alcohol use among a variety of marginalised groups in developing countries and the different policy options available for these populations. In addition, there is a need for studies that untangle the potential linkages between both historical and current exploitation of marginalized populations and alcohol use. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Lead and mercury levels in an environmentally exposed population in the Central Brazil.

PubMed

Jesus, Leda Diva Freitas de; Moreira, Maria de Fátima Ramos; Azevedo, Sayonara Vieira de; Borges, Renato Marçullo; Gomes, Regina Aderne de Almeida; Bergamini, Fernanda Pereira Baptista; Teixeira, Liliane Reis

2018-03-01

The objective was to assess the level of exposure to lead and mercury in a population in the Pantanal region in Mato Grosso State, Brazil. Blood lead (PbB) (n = 119) and urinary mercury (HgU) (n = 109) in local residents were measured by atomic absorption spectrometry. Comparison of means and correlations between variables used analysis of variance (ANOVA) and linear regression, respectively, with 95% confidence intervals. Mean PbB was 2.82 ± 1.53µg dL-1. The comparison of PbB stratified by collection site (p ≤ 0.01), work activity (p ≤ 0.01), and consumption of locally produced cow's milk (p ≤ 0.05) showed statistically significant differences. There were also positive associations between PbB and collection site (p ≤ 0.01), participants' profession (p ≤ 0.05), local milk (p ≤ 0.01), and source of drinking water (p ≤ 0.01). Mean HgU was 1.41 ± 0.98µg L-1. The levels only showed significant differences for participants' profession (p ≤ 0.01), and positive associations emerged between HgU and work activity (p ≤ 0.01) and body mass index (p ≤ 0.01). The samples showed low lead and mercury levels, similar to those found in other environmentally exposed populations. Despite these low concentrations, current knowledge on the toxicity of these metals shows that health effects can already be felt at levels that were previously considered safe, thus characterizing a health hazard.

Fibromyalgia: epidemiology and risk factors, a population-based case-control study in Lebanon.

PubMed

Moukaddem, Afaf; Chaaya, Monique; Slim, Zeinab F N; Jaffa, Miran; Sibai, Abla Mehio; Uthman, Imad

2017-02-01

To investigate the epidemiology of fibromyalgia (FM) and assess its risk factors. Using data from the 2009 Community Oriented Program for Control of Rheumatic Diseases (COPCORD) study conducted in Lebanon, a population-based case control study was performed. The sample included 34 FM patients, frequency matched with 136 controls free from any musculoskeletal complaints and randomly sampled from the population. The controls were frequency matched with cases by age and gender. The 34 female FM cases were prevalent cases which existed for a long period of time and all those who consulted a doctor were previously misdiagnosed. Family history of joint problems (OR = 4.93, 95% CI: 1.56-15.58) and working status (OR = 2.69, 95% CI: 1.04-6.93) were significant risk factors for FM, after adjusting for body mass index, distress level, smoking status and residence location. This was the first study to address the epidemiology of FM in Lebanon and the region. The chronic nature of FM that is characterized by frequent bouts of intense disabling pain and symptoms constitutes a significant health and economic burden. Clustering of cases in coastal areas was partially explained by other factors such as body mass index, distress level, smoking and work status. The high burden of FM found in our study calls for further investigation of potential risk factors of this condition. © 2015 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

Holding up the oral health safety net: the role of National Health Service Corps alumni dentists in North Carolina.

PubMed

Bhatavadekar, Neel B; Rozier, R Gary; Konrad, Thomas R

2011-06-01

  Access to oral health care among low income populations is a growing problem. The National Health Service Corps (NHSC) might increase the supply of dentists motivated to provide services for this population.   To determine if North Carolina dentists who began a service obligation with the NHSC in 1990-1999 continued to provide care for underserved populations and if they differ from non-NHSC alumni primary care dentists who started practice in the state during that same period.   All 19 NHSC alumni and 50 comparison dentists were surveyed by mail. NHSC alumni also responded to selected items in a telephone follow-up interview. The two groups were compared using difference of means tests and multivariate contingency tables.   National Health Service Corps alumni were more likely to be African-American (38%vs. 10%), work in safety net practices (84%vs. 23%), and see more publicly insured patients (60%vs. 19%) than comparison dentists. Yet their job satisfaction was comparable to non-NHSC alumni dentists. Analyses suggested that current practice in safety net settings is affected by dentists' race, altruistic motivations and previous NHSC participation. CONCLUSION AND POLICY IMPLICATION:  Targeted recruitment of African-American dentists and others wanting to work in underserved communities could amplify the effectiveness of the financial incentive of NHSC loan repayment and induce dentists to remain in 'safety net' settings. © 2011 FDI World Dental Federation.

General Relativistic Precession in Small Solar System Bodies

NASA Astrophysics Data System (ADS)

Sekhar, Aswin; Werner, Stephanie; Hoffmann, Volker; Asher, David; Vaubaillon, Jeremie; Hajdukova, Maria; Li, Gongjie

2016-10-01

Introduction: One of the greatest successes of the Einstein's General Theory of Relativity (GR) was the correct prediction of the precession of perihelion of Mercury. The closed form expression to compute this precession tells us that substantial GR precession would occur only if the bodies have a combination of both moderately small perihelion distance and semi-major axis. Minimum Orbit Intersection Distance (MOID) is a quantity which helps us to understand the closest proximity of two orbits in space. Hence evaluating MOID is crucial to understand close encounters and collision scenarios better. In this work, we look at the possible scenarios where a small GR precession in argument of pericentre (ω) can create substantial changes in MOID for small bodies ranging from meteoroids to comets and asteroids.Analytical Approach and Numerical Integrations: Previous works have looked into neat analytical techniques to understand different collision scenarios and we use those standard expressions to compute MOID analytically. We find the nature of this mathematical function is such that a relatively small GR precession can lead to drastic changes in MOID values depending on the initial value of ω. Numerical integrations were done with package MERCURY incorporating the GR code to test the same effects. Numerical approach showed the same interesting relationship (as shown by analytical theory) between values of ω and the peaks/dips in MOID values. Previous works have shown that GR precession suppresses Kozai oscillations and this aspect was verified using our integrations. There is an overall agreement between both analytical and numerical methods.Summary and Discussion: We find that GR precession could play an important role in the calculations pertaining to MOID and close encounter scenarios in the case of certain small solar system bodies (depending on their initial orbital elements). Previous works have looked into impact probabilities and collision scenarios on planets from different small body populations. This work aims to find certain sub-sets of orbits where GR could play an interesting role. Certain parallels are drawn between the cases of asteroids, comets and small perihelion distance meteoroid streams.

Work ability of Chinese migrant workers: the influence of migration characteristics.

PubMed

Han, Lu; Shi, Leiyu; Lu, Liming; Ling, Li

2014-04-13

Migrant workers have become a vital labor supply to China's economy. Their migration process and work conditions may influence their health and work ability. The work ability of migrant workers in China and the influence of the migration process on work ability have not been explored extensively in previous studies. The objective of this study is to evaluate the association of migration characteristics and work-related factors with work ability among migrant workers in the Pearl River Delta. In this cross-sectional survey, the study population consisted of 907 migrant workers from ten factories in the Pearl River Delta who were exposed to organic solvents during work. The primary dependent variable of the study was work ability, measured by the Work Ability Index (WAI). The independent variables were individual characteristics, migration characteristics, and work-related factors. Logistic regression models were used to determine the influence of different factors on work ability and three dimensions of WAI. The result shows that among migration characteristics, social support was significantly associated with all three dimensions of the work ability index. Permanent migration intention and longer length of migration were negatively associated with the mental resource dimension of WAI. WAI was also influenced by individual and work-related factors. The findings of this study suggest that expanding migrants' social networks and social support systems in their work place or living community, (i.e. expanding the functions of labor unions) would be an effective way to improve migrant workers' work ability. Improving of migrant workers' physical and psychosocial related work environments would also increase their work ability.

Assessing the Sensitivity of Different Life Stages for Sexual Disruption in Roach (Rutilus rutilus) Exposed to Effluents from Wastewater Treatment Works

PubMed Central

Liney, Katherine E.; Jobling, Susan; Shears, Jan A.; Simpson, Peter; Tyler, Charles R.

2005-01-01

Surveys of U.K. rivers have shown a high incidence of sexual disruption in populations of wild roach (Rutilus rutilus) living downstream from wastewater treatment works (WwTW), and the degree of intersex (gonads containing both male and female structural characteristics) has been correlated with the concentration of effluent in those rivers. In this study, we investigated feminized responses to two estrogenic WwTWs in roach exposed for periods during life stages of germ cell division (early life and the postspawning period). Roach were exposed as embryos from fertilization up to 300 days posthatch (dph; to include the period of gonadal sex differentiation) or as postspawning adult males, and including fish that had received previous estrogen exposure, for either 60 or 120 days when the annual event of germ cell proliferation occurs. Both effluents induced vitellogenin synthesis in both life stages studied, and the magnitude of the vitellogenic responses paralleled the effluent content of steroid estrogens. Feminization of the reproductive ducts occurred in male fish in a concentration-dependent manner when the exposure occurred during early life, but we found no effects on the reproductive ducts in adult males. Depuration studies (maintenance of fish in clean water after exposure to WwTW effluent) confirmed that the feminization of the reproductive duct was permanent. We found no evidence of ovotestis development in fish that had no previous estrogen exposure for any of the treatments. In wild adult roach that had previously received exposure to estrogen and were intersex, the degree of intersex increased during the study period, but this was not related to the immediate effluent exposure, suggesting a previously determined programming of ovotestis formation. PMID:16203238

Co-occurring substance-related and behavioral addiction problems: A person-centered, lay epidemiology approach.

PubMed

Konkolÿ Thege, Barna; Hodgins, David C; Wild, T Cameron

2016-12-01

Background and aims The aims of this study were (a) to describe the prevalence of single versus multiple addiction problems in a large representative sample and (b) to identify distinct subgroups of people experiencing substance-related and behavioral addiction problems. Methods A random sample of 6,000 respondents from Alberta, Canada, completed survey items assessing self-attributed problems experienced in the past year with four substances (alcohol, tobacco, marijuana, and cocaine) and six behaviors (gambling, eating, shopping, sex, video gaming, and work). Hierarchical cluster analyses were used to classify patterns of co-occurring addiction problems on an analytic subsample of 2,728 respondents (1,696 women and 1032 men; M age  = 45.1 years, SD age  = 13.5 years) who reported problems with one or more of the addictive behaviors in the previous year. Results In the total sample, 49.2% of the respondents reported zero, 29.8% reported one, 13.1% reported two, and 7.9% reported three or more addiction problems in the previous year. Cluster-analytic results suggested a 7-group solution. Members of most clusters were characterized by multiple addiction problems; the average number of past year addictive behaviors in cluster members ranged between 1 (Cluster II: excessive eating only) and 2.5 (Cluster VII: excessive video game playing with the frequent co-occurrence of smoking, excessive eating and work). Discussion and conclusions Our findings replicate previous results indicating that about half of the adult population struggles with at least one excessive behavior in a given year; however, our analyses revealed a higher number of co-occurring addiction clusters than typically found in previous studies.

Co-occurring substance-related and behavioral addiction problems: A person-centered, lay epidemiology approach

PubMed Central

Konkolÿ Thege, Barna; Hodgins, David C.; Wild, T. Cameron

2016-01-01

Background and aims The aims of this study were (a) to describe the prevalence of single versus multiple addiction problems in a large representative sample and (b) to identify distinct subgroups of people experiencing substance-related and behavioral addiction problems. Methods A random sample of 6,000 respondents from Alberta, Canada, completed survey items assessing self-attributed problems experienced in the past year with four substances (alcohol, tobacco, marijuana, and cocaine) and six behaviors (gambling, eating, shopping, sex, video gaming, and work). Hierarchical cluster analyses were used to classify patterns of co-occurring addiction problems on an analytic subsample of 2,728 respondents (1,696 women and 1032 men; Mage = 45.1 years, SDage = 13.5 years) who reported problems with one or more of the addictive behaviors in the previous year. Results In the total sample, 49.2% of the respondents reported zero, 29.8% reported one, 13.1% reported two, and 7.9% reported three or more addiction problems in the previous year. Cluster-analytic results suggested a 7-group solution. Members of most clusters were characterized by multiple addiction problems; the average number of past year addictive behaviors in cluster members ranged between 1 (Cluster II: excessive eating only) and 2.5 (Cluster VII: excessive video game playing with the frequent co-occurrence of smoking, excessive eating and work). Discussion and conclusions Our findings replicate previous results indicating that about half of the adult population struggles with at least one excessive behavior in a given year; however, our analyses revealed a higher number of co-occurring addiction clusters than typically found in previous studies. PMID:27829288

RX J0848.6+4453: The evolution of galaxy sizes and stellar populations in A z = 1.27 cluster

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

Jørgensen, Inger; Chiboucas, Kristin; Schiavon, Ricardo P.

2014-12-01

RX J0848.6+4453 (Lynx W) at redshift 1.27 is part of the Lynx Supercluster of galaxies. We present an analysis of the stellar populations and star formation history for a sample of 24 members of the cluster. Our study is based on deep optical spectroscopy obtained with Gemini North combined with imaging data from Hubble Space Telescope. Focusing on the 13 bulge-dominated galaxies for which we can determine central velocity dispersions, we find that these show a smaller evolution with redshift of sizes and velocity dispersions than reported for field galaxies and galaxies in poorer clusters. Our data show that themore » galaxies in RX J0848.6+4453 populate the fundamental plane (FP) similar to that found for lower-redshift clusters. The zero-point offset for the FP is smaller than expected if the cluster's galaxies are to evolve passively through the location of the FP we established in our previous work for z = 0.8-0.9 cluster galaxies and then to the present-day FP. The FP zero point for RX J0848.6+4453 corresponds to an epoch of last star formation at z{sub form}=1.95{sub −0.15}{sup +0.22}. Further, we find that the spectra of the galaxies in RX J0848.6+4453 are dominated by young stellar populations at all galaxy masses and in many cases show emission indicating low-level ongoing star formation. The average age of the young stellar populations as estimated from the strength of the high-order Balmer line Hζ is consistent with a major star formation episode 1-2 Gyr prior, which in turn agrees with z {sub form} = 1.95. These galaxies dominated by young stellar populations are distributed throughout the cluster. We speculate that low-level star formation has not yet been fully quenched in the center of this cluster, possibly because the cluster is significantly poorer than other clusters previously studied at similar redshifts, which appear to have very little ongoing star formation in their centers. The mixture in RX J0848.6+4453 of passive galaxies with young stellar populations and massive galaxies still experiencing some star formation appears similar to the galaxy populations recently identified in two z ≈ 2 clusters.« less

Dynamics of a recovering Arctic bird population: the importance of climate, density dependence, and site quality

USGS Publications Warehouse

Bruggeman, Jason E.; Swem, Ted; Andersen, David E.; Kennedy, Patricia L.; Nigro, Debora A.

2015-01-01

Intrinsic and extrinsic factors affect vital rates and population-level processes, and understanding these factors is paramount to devising successful management plans for wildlife species. For example, birds time migration in response, in part, to local and broadscale climate fluctuations to initiate breeding upon arrival to nesting territories, and prolonged inclement weather early in the breeding season can inhibit egg-laying and reduce productivity. Also, density-dependent regulation occurs in raptor populations, as territory size is related to resource availability. Arctic Peregrine Falcons (Falco peregrinus tundrius; hereafter Arctic peregrine) have a limited and northern breeding distribution, including the Colville River Special Area (CRSA) in the National Petroleum Reserve–Alaska, USA. We quantified influences of climate, topography, nest productivity, prey habitat, density dependence, and interspecific competition affecting Arctic peregrines in the CRSA by applying the Dail-Madsen model to estimate abundance and vital rates of adults on nesting cliffs from 1981 through 2002. Arctic peregrine abundance increased throughout the 1980s, which spanned the population's recovery from DDT-induced reproductive failure, until exhibiting a stationary trend in the 1990s. Apparent survival rate (i.e., emigration; death) was negatively correlated with the number of adult Arctic peregrines on the cliff the previous year, suggesting effects of density-dependent population regulation. Apparent survival and arrival rates (i.e., immigration; recruitment) were higher during years with earlier snowmelt and milder winters, and apparent survival was positively correlated with nesting season maximum daily temperature. Arrival rate was positively correlated with average Arctic peregrine productivity along a cliff segment from the previous year and initial abundance was positively correlated with cliff height. Higher cliffs with documented higher productivity (presumably indicative of higher-quality habitat), are a priority for continued protection from potential nearby development and disturbance to minimize population-level impacts. Climate change may affect Arctic peregrines in multiple ways, including through access to more snow-free nest sites and a lengthened breeding season that may increase likelihood of nest success. Our work provides insight into factors affecting a population during and after recovery, and demonstrates how the Dail-Madsen model can be used for any unmarked population with multiple years of abundance data collected through repeated surveys.

Impact of increasing tobacco taxes on working-age adults: short-term health gain, health equity and cost savings.

PubMed

Cleghorn, Christine L; Blakely, Tony; Kvizhinadze, Giorgi; van der Deen, Frederieke S; Nghiem, Nhung; Cobiac, Linda J; Wilson, Nick

2017-11-16

The health gains and cost savings from tobacco tax increase peak many decades into the future. Policy-makers may take a shorter-term perspective and be particularly interested in the health of working-age adults (given their role in economic productivity). Therefore, we estimated the impact of tobacco taxes in this population within a 10-year horizon. As per previous modelling work, we used a multistate life table model with 16 tobacco-related diseases in parallel, parameterised with rich national data by sex, age and ethnicity. The intervention modelled was 10% annual increases in tobacco tax from 2011 to 2020 in the New Zealand population (n=4.4 million in 2011). The perspective was that of the health system, and the discount rate used was 3%. For this 10-year time horizon, the total health gain from the tobacco tax in discounted quality-adjusted life years (QALYs) in the 20-65 year age group (age at QALY accrual) was 180 QALYs or 1.6% of the lifetime QALYs gained in this age group (11 300 QALYs). Nevertheless, for this short time horizon: (1) cost savings in this group amounted to NZ$10.6 million (equivalent to US$7.1 million; 95% uncertainty interval: NZ$6.0 million to NZ$17.7 million); and (2) around two-thirds of the QALY gains for all ages occurred in the 20-65 year age group. Focusing on just the preretirement and postretirement ages, the QALY gains in each of the 60-64 and 65-69 year olds were 11.5% and 10.6%, respectively, of the 268 total QALYs gained for all age groups in 2011-2020. The majority of the health benefit over a 10-year horizon from increasing tobacco taxes is accrued in the working-age population (20-65 years). There remains a need for more work on the associated productivity benefits of such health gains. © 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.

Prevalence of oro-dental pathology in a working horse population in Egypt and its relation to equine health.

PubMed

Salem, S E; Townsend, N B; Refaai, W; Gomaa, M; Archer, D C

2017-01-01

Oro-dental disease can have a significant impact on equine welfare. To determine the prevalence of oro-dental disease and to identify risk factors for oro-dental disorders and poor body condition scores (BCS) in a working horse population in Egypt. Cross-sectional survey. Oro-dental examination was performed on 450 working horses in 2 Egyptian provinces. Horse and management historical data were collected and horses were assigned to no/mild, moderate and severe dental disease categories based on findings on examination. Multivariable logistic regression and generalised additive models were used to identify risk factors for oral mucosal injuries and very poor/poor BCS, and to explore the relationship between age and different oro-dental disorders. Oro-dental disease was common, with 45.3% and 8.4% of horses considered to have moderate and severe oro-dental disease, respectively. None of these horses had previously undergone any form of proper dental examination and treatment by trained personnel. Oral mucosal injuries (64.2%) and sharp enamel points (79.8%) were most common. Oral mucosal injuries were significantly associated with increasing age (odds ratio (OR) 1.1, 95% confidence interval (CI) 1.01-1.1, P = 0.03), focal dental overgrowths (OR 2.4, 95% CI 1.4-4.0, P = 0.002) and sharp enamel points (OR 6.3, 95% CI 3.5-11.0, P<0.001). Very poor and poor BCS were significantly associated with severe dental disease (OR 2.6, 95% CI 1.2-5.8, P = 0.02), horses aged 16-30 years (OR 3.5, 95% CI 1.7-7.0, P = 0.001), height (OR 0.9, 95% CI 0.9-0.97, P = 0.001) and packed cell volume (OR 0.9, 95% CI 0.85-0.95, P<0.001). There is a need for education of working horse-owners in Egypt about the importance of oro-dental disease and for greater availability of veterinarians with suitable training and equipment to perform dental prophylaxis and treatment. Even simple dental prophylaxis could have a significant impact on the health and welfare of this population of working horses. © 2015 EVJ Ltd.

Genetic and morphological contrasts between wild and anthropogenic populations of Agave parryi var. huachucensis in south-eastern Arizona.

PubMed

Parker, Kathleen C; Trapnell, Dorset W; Hamrick, J L; Hodgson, Wendy C

2014-05-01

At least seven species of Agave, including A. parryi, were cultivated prehistorically in Arizona, serving as important sources of food and fibre. Many relict populations from ancient cultivation remain in the modern landscape, offering a unique opportunity to study pre-Columbian plant manipulation practices. This study examined genetic and morphological variation in six A. p. var. huachucensis populations of unknown origin to compare them with previous work on A. parryi populations of known origin, to infer their cultivation history and to determine whether artificial selection is evident in populations potentially managed by early agriculturalists. Six A. p. var. huachucensis and 17 A. parryi populations were sampled, and morphometric, allozyme and microsatellite data were used to compare morphology and genetic structure in purportedly anthropogenic and wild populations, as well as in the two taxa. Analysis of molecular variance and Bayesian clustering were performed to partition variation associated with taxonomic identity and hypothesized evolutionary history, to highlight patterns of similarity among populations and to identify potential wild sources for the planting stock. A p. var. huachucensis and A. parryi populations differed significantly both morphologically and genetically. Like A. parryi, wild A. p. var. huachucensis populations were more genetically diverse than the inferred anthropogenic populations, with greater expected heterozygosity, percentage of polymorphic loci and number of alleles. Inferred anthropogenic populations exhibited many traits indicative of past active cultivation: greater morphological uniformity, fixed heterozygosity for several loci (non-existent in wild populations), fewer multilocus genotypes and strong differentiation among populations. Where archaeological information is lacking, the genetic signature of many Agave populations in Arizona can be used to infer their evolutionary history and to identify potentially fruitful sites for archaeological investigation of ancient settlements and cultivation practices. The same approach can clearly be adopted for other species in similar situations.

Genetic and morphological contrasts between wild and anthropogenic populations of Agave parryi var. huachucensis in south-eastern Arizona

PubMed Central

Parker, Kathleen C.; Trapnell, Dorset W.; Hamrick, J. L.; Hodgson, Wendy C.

2014-01-01

Background and Aims At least seven species of Agave, including A. parryi, were cultivated prehistorically in Arizona, serving as important sources of food and fibre. Many relict populations from ancient cultivation remain in the modern landscape, offering a unique opportunity to study pre-Columbian plant manipulation practices. This study examined genetic and morphological variation in six A. p. var. huachucensis populations of unknown origin to compare them with previous work on A. parryi populations of known origin, to infer their cultivation history and to determine whether artificial selection is evident in populations potentially managed by early agriculturalists. Methods Six A. p. var. huachucensis and 17 A. parryi populations were sampled, and morphometric, allozyme and microsatellite data were used to compare morphology and genetic structure in purportedly anthropogenic and wild populations, as well as in the two taxa. Analysis of molecular variance and Bayesian clustering were performed to partition variation associated with taxonomic identity and hypothesized evolutionary history, to highlight patterns of similarity among populations and to identify potential wild sources for the planting stock. Key Results A p. var. huachucensis and A. parryi populations differed significantly both morphologically and genetically. Like A. parryi, wild A. p. var. huachucensis populations were more genetically diverse than the inferred anthropogenic populations, with greater expected heterozygosity, percentage of polymorphic loci and number of alleles. Inferred anthropogenic populations exhibited many traits indicative of past active cultivation: greater morphological uniformity, fixed heterozygosity for several loci (non-existent in wild populations), fewer multilocus genotypes and strong differentiation among populations. Conclusions Where archaeological information is lacking, the genetic signature of many Agave populations in Arizona can be used to infer their evolutionary history and to identify potentially fruitful sites for archaeological investigation of ancient settlements and cultivation practices. The same approach can clearly be adopted for other species in similar situations. PMID:24638822

Genetic analysis of the Hungarian draft horse population using partial mitochondrial DNA D-loop sequencing.

PubMed

Csizmár, Nikolett; Mihók, Sándor; Jávor, András; Kusza, Szilvia

2018-01-01

The Hungarian draft is a horse breed with a recent mixed ancestry created in the 1920s by crossing local mares with draught horses imported from France and Belgium. The interest in its conservation and characterization has increased over the last few years. The aim of this work is to contribute to the characterization of the endangered Hungarian heavy draft horse populations in order to obtain useful information to implement conservation strategies for these genetic stocks. To genetically characterize the breed and to set up the basis for a conservation program, in the present study a hypervariable region of the mitochrondial DNA (D-loop) was used to assess genetic diversity in Hungarian draft horses. Two hundred and eighty five sequences obtained in our laboratory and 419 downloaded sequences available from Genbank were analyzed. One hundred and sixty-four haplotypes and thirty-six polymorphic sites were observed. High haplotype and nucleotide diversity values ( H d  = 0.954 ± 0.004; π  = 0.028 ± 0.0004) were identified in Hungarian population, although they were higher within than among the different populations ( H d  = 0.972 ± 0.002; π  = 0.03097 ± 0.002). Fourteen of the previously observed seventeen haplogroups were detected. Our samples showed a large intra- and interbreed variation. There was no clear clustering on the median joining network figure. The overall information collected in this work led us to consider that the genetic scenario observed for Hungarian draft breed is more likely the result of contributions from 'ancestrally' different genetic backgrounds. This study could contribute to the development of a breeding plan for Hungarian draft horses and help to formulate a genetic conservation plan, avoiding inbreeding while.

Population Genetic Analysis Reveals a High Genetic Diversity in the Brazilian Cryptococcus gattii VGII Population and Shifts the Global Origin from the Amazon Rainforest to the Semi-arid Desert in the Northeast of Brazil.

PubMed

Souto, Ana C P; Bonfietti, Lucas X; Ferreira-Paim, Kennio; Trilles, Luciana; Martins, Marilena; Ribeiro-Alves, Marcelo; Pham, Cau D; Martins, Liline; Dos Santos, Wallace; Chang, Marilene; Brito-Santos, Fabio; Santos, Dayane C S; Fortes, Silvana; Lockhart, Shawn R; Wanke, Bodo; Melhem, Márcia S C; Lazéra, Márcia S; Meyer, Wieland

2016-08-01

Cryptococcus neoformans and Cryptococcus gattii are responsible globally for almost one million cryptococcosis cases yearly, mostly in immunocompromised patients, such as those living with HIV. Infections due to C. gattii have mainly been described in tropical and subtropical regions, but its adaptation to temperate regions was crucial in the species evolution and highlighted the importance of this pathogenic yeast in the context of disease. Cryptococcus gattii molecular type VGII has come to the forefront in connection with an on-going emergence in the Pacific North West of North America. Taking into account that previous work pointed towards South America as an origin of this species, the present work aimed to assess the genetic diversity within the Brazilian C. gattii VGII population in order to gain new insights into its origin and global dispersal from the South American continent using the ISHAM consensus MLST typing scheme. Our results corroborate the finding that the Brazilian C. gattii VGII population is highly diverse. The diversity is likely due to recombination generated from sexual reproduction, as evidenced by the presence of both mating types in clinical and environmental samples. The data presented herein strongly supports the emergence of highly virulent strains from ancestors in the Northern regions of Brazil, Amazonia and the Northeast. Numerous genotypes represent a link between Brazil and other parts of the world reinforcing South America as the most likely origin of the C. gattii VGII subtypes and their subsequent global spread, including their dispersal into North America, where they caused a major emergence.

A Cosmic Baby-Boom

NASA Astrophysics Data System (ADS)

2005-09-01

Large Population of Galaxies Found in the Young Universe with ESO's VLT The Universe was a more fertile place soon after it was formed than has previously been suspected. A team of French and Italian astronomers [1] made indeed the surprising discovery of a large and unknown population of distant galaxies observed when the Universe was only 10 to 30% its present age. ESO PR Photo 29a/05 ESO PR Photo 29a/05 New Population of Distant Galaxies [Preview - JPEG: 400 x 424 pix - 191k] [Normal - JPEG: 800 x 847 pix - 449k] [HiRes - JPEG: 2269 x 2402 pix - 2.0M] ESO PR Photo 29b/05 ESO PR Photo 29b/05 Average Spectra of Distant Galaxies [Preview - JPEG: 400 x 506 pix - 141k] [Normal - JPEG: 800 x 1012 pix - 320k] This breakthrough is based on observations made with the Visible Multi-Object Spectrograph (VIMOS) as part of the VIMOS VLT Deep Survey (VVDS). The VVDS started early 2002 on Melipal, one of the 8.2-m telescopes of ESO's Very Large Telescope Array [2]. In a total sample of about 8,000 galaxies selected only on the basis of their observed brightness in red light, almost 1,000 bright and vigorously star forming galaxies were discovered that were formed between 9 and 12 billion years ago (i.e. about 1,500 to 4,500 million years after the Big Bang). "To our surprise, says Olivier Le Fèvre, from the Laboratoire d'Astrophysique de Marseille (France) and co-leader of the VVDS project, "this is two to six times higher than had been found previously. These galaxies had been missed because previous surveys had selected objects in a much more restrictive manner than we did. And they did so to accommodate the much lower efficiency of the previous generation of instruments." While observations and models have consistently indicated that the Universe had not yet formed many stars in the first billion years of cosmic time, the discovery announced today by scientists calls for a significant change in this picture. The astronomers indeed find that stars formed two to three times faster than previously estimated. "These observations will demand a profound reassessment of our theories of the formation and evolution of galaxies in a changing Universe", says Gianpaolo Vettolani, the other co-leader of the VVDS project, working at INAF-IRA in Bologna (Italy). These results are reported in the September 22 issue of the journal Nature (Le Fèvre et al., "A large population of galaxies 9 to 12 billion years back in the life of the Universe").

Greater sage-grouse population trends across Wyoming

USGS Publications Warehouse

Edmunds, David; Aldridge, Cameron L.; O'Donnell, Michael; Monroe, Adrian

2018-01-01

The scale at which analyses are performed can have an effect on model results and often one scale does not accurately describe the ecological phenomena of interest (e.g., population trends) for wide-ranging species: yet, most ecological studies are performed at a single, arbitrary scale. To best determine local and regional trends for greater sage-grouse (Centrocercus urophasianus) in Wyoming, USA, we modeled density-independent and -dependent population growth across multiple spatial scales relevant to management and conservation (Core Areas [habitat encompassing approximately 83% of the sage-grouse population on ∼24% of surface area in Wyoming], local Working Groups [7 regional areas for which groups of local experts are tasked with implementing Wyoming's statewide sage-grouse conservation plan at the local level], Core Area status (Core Area vs. Non-Core Area) by Working Groups, and Core Areas by Working Groups). Our goal was to determine the influence of fine-scale population trends (Core Areas) on larger-scale populations (Working Group Areas). We modeled the natural log of change in population size ( peak M lek counts) by time to calculate the finite rate of population growth (λ) for each population of interest from 1993 to 2015. We found that in general when Core Area status (Core Area vs. Non-Core Area) was investigated by Working Group Area, the 2 populations trended similarly and agreed with the overall trend of the Working Group Area. However, at the finer scale where Core Areas were analyzed separately, Core Areas within the same Working Group Area often trended differently and a few large Core Areas could influence the overall Working Group Area trend and mask trends occurring in smaller Core Areas. Relatively close fine-scale populations of sage-grouse can trend differently, indicating that large-scale trends may not accurately depict what is occurring across the landscape (e.g., local effects of gas and oil fields may be masked by increasing larger populations). 

[Reference values in the usual laboratory data for sub-Saharan immigrants. Importance in the management of infectious diseases].

PubMed

Sanz-Peláez, O; Angel-Moreno, A; Tapia-Martín, M; Conde-Martel, A; Carranza-Rodríguez, C; Carballo-Rastrilla, S; Soria-López, A; Pérez-Arellano, J L

2008-09-01

The progressive increase in the number of immigrants to Spain in recent years has made it necessary for health-care professionals to be aware about the specific characteristics of this population. An attempt is made in this study to define the normal range of common laboratory values in healthy sub-Saharan adults. Common laboratory values were studied (blood cell counts, clotting tests and blood biochemistry values) and were measured in 150 sub-Saharan immigrants previously defined as healthy according to a complete health evaluation that included a clinical history, physical examination, serologic tests and study of stool parasites. These results were compared to those from a control group consisting of 81 age-and-sex matched healthy blood donors taken from the Spanish native population. Statistically significant differences were obtained in the following values. Mean corpuscular volume (MCV), red cell distribution width (RDW), total leukocytes, and serum levels of creatinine, uric acid, total protein content, creatin-kinase (CK), aspartate aminotransferase (AST), gamma-glutamyl-transpeptidase (GGT), Immunoglobulin G (IgG) and M (IgM). If evaluated according to the normal values in native people, a considerable percentage of healthy sub-Saharan immigrants would present values (with potential clinical relevance) in the following parameters. MCV, RDW, total leukocyte counts and serum levels of CK, IgG and IgM. A proper interpretation of the common laboratory values in sub-Saharan immigrants, and probably in other foreign collectives, requires a previously-established range of normality in these parameters for those populations in order to avoid diagnostic mistakes and inadequate work-up and management.

Social information in nest colonisation and occupancy in a long-lived, solitary breeding bird.

PubMed

Václav, Radovan; Valera, Francisco; Martínez, Teresa

2011-03-01

Recent work increasingly reveals the importance of social information in individual dispersal decisions, population dynamics and conservation. Much of the knowledge gained to date comes from studies on short-lived and/or densely breeding species. In contrast, our understanding of the processes involved in nest-site selection for long-lived, solitary breeding species is insufficient. We increased nest-site availability by nest-box supplementation over a 5-year period in a population of a long-lived, solitary, secondary-cavity nesting bird, the European roller Coracias garrulus, breeding in natural cavities and human constructions. We tested the nest limitation and the inadvertent conspecific social information hypothesis in order to study the dynamics and mechanisms of abandonment of previously used nests and the colonisation of new ones. Our data lend support to the nest-limitation hypothesis both in terms of quantity-population and the size of breeding clusters increased, and suitability--the majority of pairs used and re-occupied nest-boxes. Nevertheless, the use of natural cavities did not decrease after 5 years. At the between-patch scale, rollers were revealed to colonise nest-boxes based on conspecific social attraction, namely distance to the nearest neighbour in the same season. Despite the unpredictability of patch productivity, at the within--patch scale, the selection of previously unoccupied cavities was consistent with the performance-based conspecific attraction hypothesis. Philopatry could account for the repeated use of cavities, because nests that were used for two successive years were more likely to also be reused in the subsequent season.

Development of a site fidelity index based on population capture-recapture data

PubMed Central

Ferrari, Mariano A.; Crespo, Enrique A.; Coscarella, Mariano A.

2018-01-01

Background Site fidelity is considered as an animal’s tendency to return to a previously occupied place; this is a component of animal behaviour that allows us to understand movement patterns and aspects related to the animal’s life history. Although there are many site fidelity metrics, the lack of standardisation presents a considerable challenge in terms of comparability among studies. Methods This investigation focused on the theoretical development of a standardised composite site fidelity index and its statistical distribution in order to obtain reliable population-level site fidelity comparisons. The arithmetic and harmonic means were used as mathematical structures in order to create different indexes by combining the most commonly used indicators for site fidelity such as Occurrence, Permanence and Periodicity. The index performance was then evaluated in simulated populations and one real population of Commerson’s dolphins (Cephalorhynchus commersonii (Lacépède 1804)). In the first case, the indexes were evaluated based on how they were affected by different probability values such as the occurrence of the individual within the study area (φ) and capture probability (p). As a precision measure for the comparison of the indexes, the Wald confidence interval (CI) and the mean square error were applied. Given that there was no previous data concerning the distribution parameters of this population, bootstrap CIs were applied for the study case. Results Eight alternative indexes were developed. The indexes with an arithmetic mean structure, in general, had a consistently inferior performance than those with a harmonic mean structure. The index IH4, in particular, achieved the best results in all of the scenarios and in the study case. Additionally, this index presented a normal distribution. As such, it was proposed as a standardised measure for site fidelity (Standardised Site Fidelity Index—SSFI). Discussion The SSFI is the first standardised metric that quantifies site fidelity at a populational level. It is an estimator that varies between zero and one and works in situations where detection is not perfect and effort can be constant or not. Moreover, it has an associated CI that allows users to make comparisons. PMID:29761064

Development of a site fidelity index based on population capture-recapture data.

PubMed

Tschopp, Ayelen; Ferrari, Mariano A; Crespo, Enrique A; Coscarella, Mariano A

2018-01-01

Site fidelity is considered as an animal's tendency to return to a previously occupied place; this is a component of animal behaviour that allows us to understand movement patterns and aspects related to the animal's life history. Although there are many site fidelity metrics, the lack of standardisation presents a considerable challenge in terms of comparability among studies. This investigation focused on the theoretical development of a standardised composite site fidelity index and its statistical distribution in order to obtain reliable population-level site fidelity comparisons. The arithmetic and harmonic means were used as mathematical structures in order to create different indexes by combining the most commonly used indicators for site fidelity such as Occurrence, Permanence and Periodicity. The index performance was then evaluated in simulated populations and one real population of Commerson's dolphins ( Cephalorhynchus commersonii (Lacépède 1804)). In the first case, the indexes were evaluated based on how they were affected by different probability values such as the occurrence of the individual within the study area (φ) and capture probability ( p ). As a precision measure for the comparison of the indexes, the Wald confidence interval (CI) and the mean square error were applied. Given that there was no previous data concerning the distribution parameters of this population, bootstrap CIs were applied for the study case. Eight alternative indexes were developed. The indexes with an arithmetic mean structure, in general, had a consistently inferior performance than those with a harmonic mean structure. The index IH4, in particular, achieved the best results in all of the scenarios and in the study case. Additionally, this index presented a normal distribution. As such, it was proposed as a standardised measure for site fidelity (Standardised Site Fidelity Index-SSFI). The SSFI is the first standardised metric that quantifies site fidelity at a populational level. It is an estimator that varies between zero and one and works in situations where detection is not perfect and effort can be constant or not. Moreover, it has an associated CI that allows users to make comparisons.

Reconceptualizing the HIV epidemiology and prevention needs of Female Sex Workers (FSW) in Swaziland.

PubMed

Baral, Stefan; Ketende, Sosthenes; Green, Jessie L; Chen, Ping-An; Grosso, Ashley; Sithole, Bhekie; Ntshangase, Cebisile; Yam, Eileen; Kerrigan, Deanna; Kennedy, Caitlin E; Adams, Darrin

2014-01-01

HIV is hyperendemic in Swaziland with a prevalence of over 25% among those between the ages of 15 and 49 years old. The HIV response in Swaziland has traditionally focused on decreasing HIV acquisition and transmission risks in the general population through interventions such as male circumcision, increasing treatment uptake and adherence, and risk-reduction counseling. There is emerging data from Southern Africa that key populations such as female sex workers (FSW) carry a disproportionate burden of HIV even in generalized epidemics such as Swaziland. The burden of HIV and prevention needs among FSW remains unstudied in Swaziland. A respondent-driven-sampling survey was completed between August-October, 2011 of 328 FSW in Swaziland. Each participant completed a structured survey instrument and biological HIV and syphilis testing according to Swazi Guidelines. Unadjusted HIV prevalence was 70.3% (n = 223/317) among a sample of women predominantly from Swaziland (95.2%, n = 300/316) with a mean age of 21(median 25) which was significantly higher than the general population of women. Approximately one-half of the FSW(53.4%, n = 167/313) had received HIV prevention information related to sex work in the previous year, and about one-in-ten had been part of a previous research project(n = 38/313). Rape was common with nearly 40% (n = 123/314) reporting at least one rape; 17.4% (n = 23/314)reported being raped 6 or more times. Reporting blackmail (34.8%, n = 113/314) and torture(53.2%, n = 173/314) was prevalent. While Swaziland has a highly generalized HIV epidemic, reconceptualizing the needs of key populations such as FSW suggests that these women represent a distinct population with specific vulnerabilities and a high burden of HIV compared to other women. These women are understudied and underserved resulting in a limited characterization of their HIV prevention, treatment, and care needs and only sparse specific and competent programming. FSW are an important population for further investigation and rapid scale-up of combination HIV prevention including biomedical, behavioral, and structural interventions.

The Hard Work of Balancing Employment and Caregiving: What Can Canadian Employers Do to Help?

PubMed Central

Lilly, Meredith B.

2011-01-01

As a result of population aging and changing family structures, more Canadians than ever are balancing careers with family caregiving responsibilities. Previous research has suggested that different policy responses are required to support caregivers, depending on the intensity of their caregiving contributions. This discussion paper focuses on needed workplace supports for family caregivers in Canada, with a specific emphasis on the role for employers. Outlined are challenges faced by caregiving employees, the ways in which employers and governments are already supporting caregivers internationally, and options for how Canadian employers might participate in creating caregiver-friendly workplaces. PMID:23115566

Characterization of aerosolized bacteria and fungi from desert dust events in Mali, West Africa

USGS Publications Warehouse

Kellogg, C.A.; Griffin, Dale W.; Garrison, V.H.; Peak, K.K.; Royall, N.; Smith, R.R.; Shinn, E.A.

2004-01-01

Millions of metric tons of African desert dust blow across the Atlantic Ocean each year, blanketing the Caribbean and southeastern United States. Previous work in the Caribbean has shown that atmospheric samples collected during dust events contain living microbes, including plant and opportunistic human pathogens. To better understand the potential downwind public health and ecosystem effects of the dust microbes, it is important to characterize the source population. We describe 19 genera of bacteria and 3 genera of fungi isolated from air samples collected in Mali, a known source region for dust storms, and over which large dust storms travel.

Quantum turbulence and correlations in Bose-Einstein condensate collisions

NASA Astrophysics Data System (ADS)

Norrie, A. A.; Ballagh, R. J.; Gardiner, C. W.

2006-04-01

We investigate numerically simulated collisions between experimentally realistic Bose-Einstein condensate wave packets, within a regime where highly populated scattering haloes are formed. The theoretical basis for this work is the truncated Wigner method, for which we present a detailed derivation, paying particular attention to its validity regime for colliding condensates. This paper is an extension of our previous Letter [A. A. Norrie, R. J. Ballagh, and C. W. Gardiner, Phys. Rev. Lett. 94, 040401 (2005)], and we investigate both single-trajectory solutions, which reveal the presence of quantum turbulence in the scattering halo, and ensembles of trajectories, which we use to calculate quantum-mechanical correlation functions of the field.

A New Determination of the Extragalactic Diffuse X-Ray Background from EGRET Data

NASA Technical Reports Server (NTRS)

Strong, Andrew W.; Moskalenko, Igor V.; Reimer, Olaf

2004-01-01

We use the GALPROP model for cosmic-ray propagation to obtain a new estimate of the Galactic component of gamma rays, and show that away from the Galactic plane it gives an accurate prediction of the observed EGRET intensities in the energy range 30 MeV - 50 GeV. On this basis we re-evaluate the extragalactic gamma-ray background. We find that for some energies previous work underestimated the Galactic contribution at high latitudes and hence overestimated the background. Our new background spectrum shows a positive curvature similar to that expected for models of the extragalactic emission based on the blazar population.

Multiple core-hole formation by free-electron laser radiation in molecular nitrogen

NASA Astrophysics Data System (ADS)

Banks, H. I. B.; Little, D. A.; Emmanouilidou, A.

2018-05-01

We investigate the formation of multiple-core-hole states of molecular nitrogen interacting with a free-electron laser pulse. In previous work, we obtained bound and continuum molecular orbitals in the single-center expansion scheme and used these orbitals to calculate photo-ionization and auger decay rates. We extend our formulation to track the proportion of the population that accesses single-site versus two-site double-core-hole (TSDCH) states, before the formation of the final atomic ions. We investigate the pulse parameters that favor the formation of the single-site and TSDCH as well as triple-core-hole states for 525 and 1100 eV photons.

Generating functionals and Gaussian approximations for interruptible delay reactions

NASA Astrophysics Data System (ADS)

Brett, Tobias; Galla, Tobias

2015-10-01

We develop a generating functional description of the dynamics of non-Markovian individual-based systems in which delay reactions can be terminated before completion. This generalizes previous work in which a path-integral approach was applied to dynamics in which delay reactions complete with certainty. We construct a more widely applicable theory, and from it we derive Gaussian approximations of the dynamics, valid in the limit of large, but finite, population sizes. As an application of our theory we study predator-prey models with delay dynamics due to gestation or lag periods to reach the reproductive age. In particular, we focus on the effects of delay on noise-induced cycles.