Importance of population-based studies in clinical practice

PubMed Central

Ronnie, George; Ve, Ramesh Sathyamangalam; Velumuri, Lokapavani; Asokan, Rashima; Vijaya, Lingam

2011-01-01

In the last decade, there have been reports on the prevalence of glaucoma from the Vellore Eye Survey, Andhra Pradesh Eye Diseases Survey, Aravind Comprehensive Eye Survey, Chennai Glaucoma Study and West Bengal Glaucoma Study. Population-based studies provide important information regarding the prevalence and risk factors for glaucoma. They also highlight regional differences in the prevalence of various types of glaucoma. It is possible to gather important insights regarding the number of persons affected with glaucoma and the proportion with undiagnosed disease. We reviewed the different population-based studies from India and compare their findings. The lacunae in ophthalmic care that can be inferred from these studies are identified and possible reasons and solutions are discussed. We also discuss the clinical relevance of the various findings, and how it reflects on clinical practice in the country. Since India has a significantly high disease burden, we examine the possibility of population-based screening for disease in the Indian context. PMID:21150021

What population studies can do for business.

PubMed

Hugo, G

1991-05-01

This paper examines how specific skills essential to demography, the scientific study of human populations, can be useful in private and public sector planning. Over the past 2 decades, Australia's population has undergone profound transformations -- a shift to below replacement level fertility and a change in ethnic composition, to name a few. And these changes have reshaped the markets for goods, services, and labor. Because demography seeks to analyze and explain changes in the size, composition, and spatial distribution of people, this discipline requires certain skills that can be particularly valuable to both private and public sector planning. These skills include: 1) a sound knowledge of why and how populations change over time; 2) a wide range of concepts (the "cohort," for example) which allow demographers to analyze the dynamics of change in a population; 3) statistical techniques; and 4) life tables techniques. Having named the specific skills of demographers, the author identifies the areas of business and public administration where these skills can be most useful, areas that include the following: strategic long-term planning, marketing, market segmentation, small area analysis, household and family level analysis, projections and estimates, human resources analysis, and international population trends. Finally, the author discusses the implications of applied population analysis on the training of demographers in Australia, emphasizing the role of the Australian Population Association in improving the status of demography as an important planning tool.

Matrix population models from 20 studies of perennial plant populations

USGS Publications Warehouse

Ellis, Martha M.; Williams, Jennifer L.; Lesica, Peter; Bell, Timothy J.; Bierzychudek, Paulette; Bowles, Marlin; Crone, Elizabeth E.; Doak, Daniel F.; Ehrlen, Johan; Ellis-Adam, Albertine; McEachern, Kathryn; Ganesan, Rengaian; Latham, Penelope; Luijten, Sheila; Kaye, Thomas N.; Knight, Tiffany M.; Menges, Eric S.; Morris, William F.; den Nijs, Hans; Oostermeijer, Gerard; Quintana-Ascencio, Pedro F.; Shelly, J. Stephen; Stanley, Amanda; Thorpe, Andrea; Tamara, Ticktin; Valverde, Teresa; Weekley, Carl W.

2012-01-01

Demographic transition matrices are one of the most commonly applied population models for both basic and applied ecological research. The relatively simple framework of these models and simple, easily interpretable summary statistics they produce have prompted the wide use of these models across an exceptionally broad range of taxa. Here, we provide annual transition matrices and observed stage structures/population sizes for 20 perennial plant species which have been the focal species for long-term demographic monitoring. These data were assembled as part of the "Testing Matrix Models" working group through the National Center for Ecological Analysis and Synthesis (NCEAS). In sum, these data represent 82 populations with >460 total population-years of data. It is our hope that making these data available will help promote and improve our ability to monitor and understand plant population dynamics.

Matrix population models from 20 studies of perennial plant populations

USGS Publications Warehouse

Ellis, Martha M.; Williams, Jennifer L.; Lesica, Peter; Bell, Timothy J.; Bierzychudek, Paulette; Bowles, Marlin; Crone, Elizabeth E.; Doak, Daniel F.; Ehrlen, Johan; Ellis-Adam, Albertine; McEachern, Kathryn; Ganesan, Rengaian; Latham, Penelope; Luijten, Sheila; Kaye, Thomas N.; Knight, Tiffany M.; Menges, Eric S.; Morris, William F.; den Nijs, Hans; Oostermeijer, Gerard; Quintana-Ascencio, Pedro F.; Shelly, J. Stephen; Stanley, Amanda; Thorpe, Andrea; Tamara, Ticktin; Valverde, Teresa; Weekley, Carl W.

2012-01-01

Demographic transition matrices are one of the most commonly applied population models for both basic and applied ecological research. The relatively simple framework of these models and simple, easily interpretable summary statistics they produce have prompted the wide use of these models across an exceptionally broad range of taxa. Here, we provide annual transition matrices and observed stage structures/population sizes for 20 perennial plant species which have been the focal species for long-term demographic monitoring. These data were assembled as part of the 'Testing Matrix Models' working group through the National Center for Ecological Analysis and Synthesis (NCEAS). In sum, these data represent 82 populations with >460 total population-years of data. It is our hope that making these data available will help promote and improve our ability to monitor and understand plant population dynamics.

A Study of Optimum Population Levels—A Progress Report*

PubMed Central

Singer, S. Fred

1972-01-01

The purpose of this study is to explore different approaches and to develop a methodology that will allow a calculation of “optimum levels of population.” The discussion is specialized to the United States, but the methodology should be broad enough to handle other countries, including less-developed countries. The study is based on economics, but with major inputs from the areas of technology, natural resources management, environmental effects, and demography. The general approach will be to develop an index for quality of life (IQL or Q-index) and to maximize this index as a function of level and distribution of population. The technique consists of a reshuffling of national income accounts so as to be able to go from the Gross National Product (GNP) to the index for quality of life, plus a careful discussion of what is and what is not to be included. The initial part of the study consists of a projection of the index for quality of life as population level increases and as population distribution changes, under the assumption of various technologies, particularly as these relate to the consumption of minerals, energy, and other natural resources. One would expect that as economic growth continues, an increasing fraction of expenditures would be for the diseconomics produced by population growth and economic growth. This study should be useful by providing a rational base for governmental policies regarding population, both in the United States and abroad. Another application of the study is to technology assessment, by measurement of the impact on economic well-being through the introduction of new technologies. Therefore, one can gauge the necessary and desirable investments in certain new technologies. In general, mathematical models resulting from this study can become useful diagnostic tools to analyze the consequences of various public and private policy decisions. PMID:4509346

Econometric studies of urban population density: a survey.

PubMed

Mcdonald, J F

1989-01-01

This paper presents the 1st reasonably comprehensive survey of empirical research of urban population densities since the publication of the book by Edmonston in 1975. The survey summarizes contributions to empirical knowledge that have been made since 1975 and points toward possible areas for additional research. The paper also provides a brief interpretative intellectual history of the topic. It begins with a personal overview of research in the field. The next section discusses econometric issues that arise in the estimation of population density functions in which density is a function only of a distance to the central business district of the urban area. Section 4 summarizes the studies of a single urban area that went beyond the estimation of simple distance-density functions, and Section 5 discusses studies that sought to explain the variations across urban areas in population density patterns. McDonald refers to the standard theory of urban population density throughout the paper. This basic model is presented in the textbook by Mills and Hamilton and it is assumed that the reader is familiar with the model.

Identification of dietary patterns in urban population of Argentina: study on diet-obesity relation in population-based prevalence study.

PubMed

Pou, Sonia Alejandra; Del Pilar Díaz, María; De La Quintana, Ana Gabriela; Forte, Carla Antonella; Aballay, Laura Rosana

2016-12-01

In Argentina, obesity prevalence rose from 14.6% in 2005 to 20.8% in 2013. Although the number of studies on noncommunicable diseases and dietary patterns as a unique dietary exposure measure has increased, information on this topic remains scarce in developing countries. This is the first population-based study investigating the association between diet and obesity using a dietary pattern approach in Argentina. We aimed (a) to identify current dietary patterns of the population of Córdoba city, (b) to investigate its association with obesity prevalence, and (c) to identify and describe dietary patterns from the subgroup of people with obesity. The Córdoba Obesity and Diet Study (CODIES) was conducted in Córdoba city by using a random sample of n = 4,327 subjects between 2005 and 2012. Empirically derived dietary patterns were identified through principal component factor analysis. A multiple logistic regression analysis was used to investigate the association of dietary patterns with obesity. Four dietary patterns were identified, called " Starchy-Sugar ", " Prudent ", " Western ", and " Sugary drinks ". High scores for the " Western " pattern (with strongest factor loading on meats/eggs, processed meats, and alcohol) showed a positive association with obesity (OR: 1.33, 95% CI: 1.06-1.67, for third versus first tertile of factor score). " Meats/Cheeses " and " Snacks/Alcohol " patterns emerged in people with obesity. The findings suggest that high adherence to the " Western " pattern promoted obesity in this urban population. In addition, people with obesity showed characteristic dietary patterns that differ from those identified in the overall population.

Studying Health Outcomes in Farmworker Populations Exposed to Pesticides

PubMed Central

McCauley, Linda A.; Anger, W. Kent; Keifer, Matthew; Langley, Rick; Robson, Mark G.; Rohlman, Diane

2006-01-01

A major goal of studying farmworkers is to better understand how their work environment, including exposure to pesticides, affects their health. Although a number of health conditions have been associated with pesticide exposure, clear linkages have yet to be made between exposure and health effects except in cases of acute pesticide exposure. In this article, we review the most common health end points that have been studied and describe the epidemiologic challenges encountered in studying these health effects of pesticides among farmworkers, including the difficulties in accessing the population and challenges associated with obtaining health end point data. The assessment of neurobehavioral health effects serves as one of the most common and best examples of an approach used to study health outcomes in farmworkers and other populations exposed to pesticides. We review the current limitations in neurobehavioral assessment and strategies to improve these analytical methods. Emerging techniques to improve our assessment of health effects associated with pesticide exposure are reviewed. These techniques, which in most cases have not been applied to farmworker populations, hold promise in our ability to study and understand the relationship between pesticide exposure and a variety of health effects in this population. PMID:16760000

Population Education in Social Studies: Some Sample Lessons.

ERIC Educational Resources Information Center

United Nations Educational, Scientific, and Cultural Organization, Bangkok (Thailand). Regional Office for Education in Asia and Oceania.

This booklet contains sample lessons and learning materials from the countries of Asia and Oceania for teaching population education in social studies. The booklet is one of a series of six, each of which brings out population education concepts as part of a particular subject area. The subject areas treated in the other booklets are home…

Human population studies and the World Health Organization.

PubMed

de Chadarevian, Soraya

2015-01-01

This essay draws attention to the role of the WHO in shaping research agendas in the biomedical sciences in the postwar era. It considers in particular the genetic studies of human populations that were pursued under the aegis of the WHO from the late 1950s to 1970s. The study provides insights into how human and medical genetics entered the agenda of the WHO. At the same time, the population studies become a focus for tracking changing notions of international relations, cooperation, and development and their impact on research in biology and medicine in the post-World War I era. After a brief discussion of the early history of the WHO and its position in Cold War politics, the essay considers the WHO program in radiation protection and heredity and how the genetic study of "vanishing" human populations and a world-wide genetic study of newborns fitted this broader agenda. It then considers in more detail the kind of support offered by the WHO for these projects. The essay highlights the role of single individuals in taking advantage of WHO support for pushing their research agendas while establishing a trend towards cooperative international projects in biology.

Multidisciplinary population monitoring when demographic data are sparse: a case study of remote trout populations

PubMed Central

Fraser, Dylan J; Calvert, Anna M; Bernatchez, Louis; Coon, Andrew

2013-01-01

The potential of genetic, genomic, and phenotypic metrics for monitoring population trends may be especially high in isolated regions, where traditional demographic monitoring is logistically difficult and only sporadic sampling is possible. This potential, however, is relatively underexplored empirically. Over eleven years, we assessed several such metrics along with traditional ecological knowledge and catch data in a socioeconomically important trout species occupying a large, remote lake. The data revealed largely stable characteristics in two populations over 2–3 generations, but possible contemporary changes in a third population. These potential shifts were suggested by reduced catch rates, reduced body size, and changes in selection implied at one gene-associated single nucleotide polymorphism. A demographic decline in this population, however, was ambiguously supported, based on the apparent lack of temporal change in effective population size, and corresponding traditional knowledge suggesting little change in catch. We illustrate how the pluralistic approach employed has practicality for setting future monitoring efforts of these populations, by guiding monitoring priorities according to the relative merits of different metrics and availability of resources. Our study also considers some advantages and disadvantages to adopting a pluralistic approach to population monitoring where demographic data are not easily obtained. PMID:24455128

Microzooplankton biomass distribution in Terra Nova Bay, Ross Sea (Antarctica)

NASA Astrophysics Data System (ADS)

Fonda Umani, S.; Monti, M.; Nuccio, C.

1998-11-01

This work describes the spatial and vertical distribution of microzooplankton (20-200 μm) abundance and biomass of the upper layers (0-100 m), collected during the first oceanographic Italian expedition in Antarctica (1987/1988) in Terra Nova Bay (Ross Sea). Biomass was estimated by using biovolume calculations and literature conversion factors. Sampling was carried out at three depths, surface, 50 and 100 m. The dominant taxa were made up of tintinnid ciliates, ciliates other than tintinnids, larvae of micrometazoa and heterotrophic dinoflagellates. The abundance of the total microplankton fraction had its absolute maximum in the center of Terra Nova Bay at the surface with 31 042 ind. dm -3. The areal and vertical distribution of heterotrophic microplankton biomass differs from that of abundance. On the basis of hydrological conditions, phytoplankton composition and biomass and microzooplankton biomass and structure it is possible to identify three groups of stations: 1—northern coastal stations (intermediate chlorophyll maxima, microphytoplankton prevalence, low microzooplankton biomass); 2—central stations (high surface chlorophyll, nanoplankton prevalence, high abundance of microzooplankton); 3—northern stations (deeper pycnocline, nanoplankton prevalence, high microzooplankton biomass at intermediate depths).

A rangewide population genetic study of trumpeter swans

USGS Publications Warehouse

Oyler-McCance, S.J.; Ransler, F.A.; Berkman, L.K.; Quinn, T.W.

2007-01-01

For management purposes, the range of naturally occurring trumpeter swans (Cygnus buccinator) has been divided into two populations, the Pacific Coast Population (PP) and the Rocky Mountain Population (RMP). Little is known about the distribution of genetic variation across the species' range despite increasing pressure to make difficult management decisions regarding the two populations and flocks within them. To address this issue, we used rapidly evolving genetic markers (mitochondrial DNA sequence and 17 nuclear microsatellite loci) to elucidate the underlying genetic structure of the species. Data from both markers revealed a significant difference between the PP and RMP with the Yukon Territory as a likely area of overlap. Additionally, we found that the two populations have somewhat similar levels of genetic diversity (PP is slightly higher) suggesting that the PP underwent a population bottleneck similar to a well-documented one in the RMP. Both genetic structure and diversity results reveal that the Tri-State flock, a suspected unique, non-migratory flock, is not genetically different from the Canadian flock of the RMP and need not be treated as a unique population from a genetic standpoint. Finally, trumpeter swans appear to have much lower mitochondrial DNA variability than other waterfowl studied thus far which may suggest a previous, species-wide bottleneck. ?? 2007 Springer Science+Business Media, Inc.

Ethiopian Population Dermatoglyphic Study Reveals Linguistic Stratification of Diversity

PubMed Central

2015-01-01

The manifestation of ethnic, blood type, & gender-wise population variations regarding Dermatoglyphic manifestations are of interest to assess intra-group diversity and differentiation. The present study reports on the analysis of qualitaive and quantitative finger Dermatoglyphic traits of 382 individuals cross-sectionally sampled from an administrative region of Ethiopia, consisting of five ethnic cohorts from the Afro-Asiatic & Nilo-Saharan affiliations. These Dermatoglyphic parameters were then applied in the assessment of diversity & differentiation, including Heterozygosity, Fixation, Panmixia, Wahlund’s variance, Nei’s measure of genetic diversity, and thumb & finger pattern genotypes, which were inturn used in homology inferences as summarized by a Neighbour-Joining tree constructed from Nei’s standard genetic distance. Results revealed significant correlation between Dermatoglyphics & population parameters that were further found to be in concordance with the historical accounts of the ethnic groups. Such inductions as the ancient north-eastern presence and subsequent admixure events of the Oromos (PII= 15.01), the high diversity of the Amharas (H= 0.1978, F= 0.6453, and P= 0.4144), and the Nilo-Saharan origin of the Berta group (PII= 10.66) are evidences to this. The study has further tested the possibility of applying Dermatoglyphics in population genetic & anthropologic research, highlighting on the prospect of developing a method to trace back population origins & ancient movement patterns. Additionally, linguistic clustering was deemed significant for the Ethiopian population, coinciding with recent genome wide studies that have ascertained that linguistic clustering as to being more crucial than the geographical patterning in the Ethiopian context. Finally, Dermatoglyphic markers have been proven to be endowed with a strong potential as non-invasive preliminary tools applicable prior to genetic studies to analyze ethnically sub

Anatomical Study of the Clavicles in a Chinese Population

PubMed Central

Qiu, Xu-sheng; Wang, Xiao-bo; Zhang, Yan; Zhu, Yan-Cheng; Guo, Xia; Chen, Yi-xin

2016-01-01

Background. A reemergence of interest in clavicle anatomy was prompted because of the advocacy for operative treatment of midshaft clavicle fractures. Several anatomical studies of the clavicle have been performed in western population. However, there was no anatomical study of clavicle in Chinese population. Patients and Methods. 52 patients were included in the present study. Three-dimensional reconstructions of the clavicles were generated. The length of the clavicle, the widths and thicknesses of the clavicle, curvatures of the clavicle, the areas of the intramedullary canal, and sectional areas of the clavicle were measured. All the measurements were compared between genders and two sides. Results. The mean length of the clavicles was 144.2 ± 12.0 mm. Clavicles in males were longer, wider, and thicker than in females; also males have different curvatures in both planes compared with females. The men's intramedullary canals and sectional areas of the clavicle were larger than those of women. No significant difference between the sides was found for all the measurements. Conclusion. This study provided an anatomical data of the clavicle in a Chinese population. These clavicle dimensions can be applied to the modifications of the contemporary clavicle plate or a new development for the Chinese population. PMID:27088088

Variability in copepod trophic levels and feeding selectivity based on stable isotope analysis in Gwangyang Bay of the southern coast of the Korean Peninsula

NASA Astrophysics Data System (ADS)

Chen, Mianrun; Kim, Dongyoung; Liu, Hongbin; Kang, Chang-Keun

2018-04-01

Trophic preference (i.e., food resources and trophic levels) of different copepod groups was assessed along a salinity gradient in the temperate estuarine Gwangyang Bay of Korea, based on seasonal investigation of taxonomic results in 2015 and stable isotope analysis incorporating multiple linear regression models. The δ13C and δ15N values of copepods in the bay displayed significant spatial heterogeneity as well as seasonal variations, which were indicated by their significant relationships with salinity and temperature, respectively. Both spatial and temporal variations reflected those in isotopic values of food sources. The major calanoid groups (marine calanoids and brackish water calanoids) had a mean trophic level of 2.2 relative to nanoplankton as the basal food source, similar to the bulk copepod assemblage; however, they had dissimilar food sources based on the different δ13C values. Calanoid isotopic values indicated a mixture of different genera including species with high δ15N values (e.g., Labidocera, Sinocalanus, and Tortanus), moderate values (Calanus sinicus, Centropages, Paracalanus, and Acartia), and relatively low δ15N values (Eurytemora pacifica and Pseudodiaptomus). Feeding preferences of different copepods probably explain these seasonal and spatial patterns of the community trophic niche. Bayesian mixing model calculations based on source materials of two size fractions of particulate organic matter (nanoplankton at < 20 µm vs. microplankton at 20-200 µm) indicated that Acartia and Centropages preferred large particles; Paracalanus, Calanus, Eurytemora, and Pseudodiaptomus apparently preferred small particles. Tortanus was typically carnivorous with low selectivity on different copepods. Labidocera preferred marine calanoids Acartia, Centropages, and harpacticoids; on the other hand, Sinocalanus and Corycaeus preferred brackish calanoids Paracalanus and Pseudodiaptomus. Overall, our results depict a simple energy flow of the planktonic

X-chromosome as a marker for population history: linkage disequilibrium and haplotype study in Eurasian populations

PubMed Central

Laan, Maris; Wiebe, Victor; Khusnutdinova, Elza; Remm, Maido; Pääbo, Svante

2005-01-01

Linkage disequilibrium structure is still unpredictable because the interplay of regional recombination rate and demographic history is poorly understood. We have compared the distribution of LD across two genomic regions differing in crossing-over activity – Xq13 (0.166 cM/Mb) and Xp22 (1.3 cM/Mb) – in 15 Eurasian populations. Demographic events predicted to increase the LD level – genetic drift, bottleneck and admixture – had a very strong impact on extent and patterns of regional LD across Xq13 compared to Xp22. The haplotype distribution of the DXS1225-DXS8082 microsatellites from Xq13 exhibiting strong association in all populations was remarkably influenced by population history. European populations shared one common haplotype with a frequency of 25-40%. The Volga-Ural populations studied, living at the geographic borderline of Europe, showed elevated LD as well as harboring a significant fraction of haplotypes originating from East Asia, thus reflecting their past migrations and admixture. In the young Kuusamo isolate from Finland, a bottleneck has led to allelic associations between loci and shifted the haplotype distribution, but has much less affected single microsatellite allele frequencies compared to the main Finnish population. The data show that the footprint of a demographic event is longer preserved in haplotype distribution within a region of low crossing-over rate, than in the information content of a single marker, or between actively recombining markers. As the knowledge of LD patterns is often chosen to assist association mapping of common disease, our conclusions emphasise the importance of understanding the history, structure and variation of a study population. PMID:15657606

Correction of Population Stratification in Large Multi-Ethnic Association Studies

PubMed Central

Serre, David; Montpetit, Alexandre; Paré, Guillaume; Engert, James C.; Yusuf, Salim; Keavney, Bernard; Hudson, Thomas J.; Anand, Sonia

2008-01-01

Background The vast majority of genetic risk factors for complex diseases have, taken individually, a small effect on the end phenotype. Population-based association studies therefore need very large sample sizes to detect significant differences between affected and non-affected individuals. Including thousands of affected individuals in a study requires recruitment in numerous centers, possibly from different geographic regions. Unfortunately such a recruitment strategy is likely to complicate the study design and to generate concerns regarding population stratification. Methodology/Principal Findings We analyzed 9,751 individuals representing three main ethnic groups - Europeans, Arabs and South Asians - that had been enrolled from 154 centers involving 52 countries for a global case/control study of acute myocardial infarction. All individuals were genotyped at 103 candidate genes using 1,536 SNPs selected with a tagging strategy that captures most of the genetic diversity in different populations. We show that relying solely on self-reported ethnicity is not sufficient to exclude population stratification and we present additional methods to identify and correct for stratification. Conclusions/Significance Our results highlight the importance of carefully addressing population stratification and of carefully “cleaning” the sample prior to analyses to obtain stronger signals of association and to avoid spurious results. PMID:18196181

Institute for the Study of Sparsely Populated Areas. A Centre for Interdisciplinary Research into Sparsely Populated and Peripheral Regions.

ERIC Educational Resources Information Center

Sadler, Peter G.

The Institute for the Study of Sparsely Populated Areas is a multidisciplinary research unit which acts to coordinate, further, and initiate studies of the economic and social conditions of sparsely populated areas. Short summaries of the eight studies completed in the session of 1977-78 indicate work in such areas as the study of political life…

Sex change and effective population size: implications for population genetic studies in marine fish.

PubMed

Coscia, I; Chopelet, J; Waples, R S; Mann, B Q; Mariani, S

2016-10-01

Large variance in reproductive success is the primary factor that reduces effective population size (Ne) in natural populations. In sequentially hermaphroditic (sex-changing) fish, the sex ratio is typically skewed and biased towards the 'first' sex, while reproductive success increases considerably after sex change. Therefore, sex-changing fish populations are theoretically expected to have lower Ne than gonochorists (separate sexes), assuming all other parameters are essentially equal. In this study, we estimate Ne from genetic data collected from two ecologically similar species living along the eastern coast of South Africa: one gonochoristic, the 'santer' sea bream Cheimerius nufar, and one protogynous (female-first) sex changer, the 'slinger' sea bream Chrysoblephus puniceus. For both species, no evidence of genetic structuring, nor significant variation in genetic diversity, was found in the study area. Estimates of contemporary Ne were significantly lower in the protogynous species, but the same pattern was not apparent over historical timescales. Overall, our results show that sequential hermaphroditism may affect Ne differently over varying time frames, and that demographic signatures inferred from genetic markers with different inheritance modes also need to be interpreted cautiously, in relation to sex-changing life histories.

Wealth Inequality and Mental Disability Among the Chinese Population: A Population Based Study.

PubMed

Wang, Zhenjie; Du, Wei; Pang, Lihua; Zhang, Lei; Chen, Gong; Zheng, Xiaoying

2015-10-19

In the study described herein, we investigated and explored the association between wealth inequality and the risk of mental disability in the Chinese population. We used nationally represented, population-based data from the second China National Sample Survey on Disability, conducted in 2006. A total of 1,724,398 study subjects between the ages of 15 and 64, including 10,095 subjects with mental disability only, were used for the analysis. Wealth status was estimated by a wealth index that was derived from a principal component analysis of 10 household assets and four other variables related to wealth. Logistic regression analysis was used to estimate the odds ratio (OR) and 95% confidence interval (CI) for mental disability for each category, with the lowest quintile category as the referent. Confounding variables under consideration were age, gender, residence area, marital status, ethnicity, education, current employment status, household size, house type, homeownership and living arrangement. The distribution of various types and severities of mental disability differed significantly by wealth index category in the present population. Wealth index category had a positive association with mild mental disability (p for trend <0.01), but had a negative association with extremely severe mental disability (p for trend <0.01). Moreover, wealth index category had a significant, inverse association with mental disability when all severities of mental disability were taken into consideration. This study's results suggest that wealth is a significant factor in the distribution of mental disability and it might have different influences on various types and severities of mental disability.

Potential for parasite-induced biases in aquatic invertebrate population studies

USGS Publications Warehouse

Fisher, Justin D.L.; Mushet, David M.; Stockwell, Craig A.

2014-01-01

Recent studies highlight the need to include estimates of detection/capture probability in population studies. This need is particularly important in studies where detection and/or capture probability is influenced by parasite-induced behavioral alterations. We assessed potential biases associated with sampling a population of the amphipod Gammarus lacustris in the presence of Polymorphus spp. acanthocephalan parasites shown to increase positive phototaxis in their amphipod hosts. We trapped G. lacustris at two water depths (benthic and surface) and compared number of captures and number of parasitized individuals at each depth. While we captured the greatest number of G. lacustris individuals in benthic traps, parasitized individuals were captured most often in surface traps. These results reflect the phototaxic movement of infected individuals from benthic locations to sunlit surface waters. We then explored the influence of varying infection rates on a simulated population held at a constant level of abundance. Simulations resulted in increasingly biased abundance estimates as infection rates increased. Our results highlight the need to consider parasite-induced biases when quantifying detection and/or capture probability in studies of aquatic invertebrate populations.

Epidemiology of suicide in Israel: a nationwide population study.

PubMed

Lubin, G; Glasser, S; Boyko, V; Barell, V

2001-03-01

In Israel, some population characteristics and lifestyle patterns make epidemiological research on suicide of particular interest. The Israeli population is characterized by ethnic diversity, with a multi-religious, multi-national mosaic of Jews and Arabs. These subgroups also vary in their suicidal behavior. The aims of the present study were to examine the trends in suicide incidence rates in Israel from 1984 to 1994, to identify sub-populations at high risk for suicide and to identify suicide methods associated with increased risk. Suicide rate trends in Israel over the period from 1984 to 1994 were examined for four subgroups: Jewish men and women, and Arab men and women. Cases of undetermined external cause (UEC) of death were also considered. Mortality data were obtained from the computerized data files of the Israeli Central Bureau of Statistics, which includes cause of death and sociodemographic variables. Suicide was classified according to the ICD-9 codes. Suicide rates were higher for Jews than for Arabs, and higher for men than for women. The rates among both population and sex groups increased directly with age. A significant increase over the years studied was found for Jewish men, particularly in the 18- to 21-year-old age group. An increase in the use of firearms was noted, mainly in the groups in which total suicide rates increased. The findings of this study highlight the need for further studies to identify both sub-populations at high risk for suicide, and societal trends such as lifestyles, immigration, military service, and media exposure to violence, as first steps toward planning of intervention programs to reduce suicide rates.

Thyroid dysfunction in an adult female population: A population-based study of Latin American Vertebral Osteoporosis Study (LAVOS) - Puerto Rico site.

PubMed

González-Rodríguez, Loida A; Felici-Giovanini, Marcos E; Haddock, Lillian

2013-06-01

To determine the prevalence of hypothyroidism in an adult female population in Puerto Rico and to determine the relationship between hypothyroidism, bone mineral density and vertebral and non-vertebral fractures in this population. Data from the 400 subjects' database of the Latin American Vertebral Osteoporosis Study (LAVOS), Puerto Rico site was reviewed. Patient's medical history, anthropometric data, current medications, laboratories, and DXA results was extracted. Subjects with thyroid dysfunction were identified based on their previous medical history and levels of TSH. Bone Mineral Density was classified using the World Health Organization criteria. Crude prevalence of thyroid dysfunction were estimated with a confidence of 95% and weighted by the population distribution by age, according to the distribution by age group in the 2000 census. Bone mineral densities and prevalence of vertebral and non-vertebral fractures were compared among the groups. The weighted prevalence of hyperthyroidism in this population was 0.0043% (95% CI: -0.0021%, 0.0107%). The weighted prevalence of hypothyroidism was 24.2% (95% CI: 19.9%, 28.4%). Increased prevalence of hypothyroidism was found in participants 70 years or older. The mean BMD at spine, hip and femoral neck was similar among the groups. No difference in the proportion of participants with vertebral and non-vertebral fractures was found among the groups. Our study found a high prevalence of hypothyroidism among adult postmenopausal females in Puerto Rico. No association between hypothyroidism and decreased bone mineral densities, vertebral or non-vertebral fractures was found in this population.

Febrile seizures: a population-based study.

PubMed

Dalbem, Juliane S; Siqueira, Heloise H; Espinosa, Mariano M; Alvarenga, Regina P

2015-01-01

To determine the prevalence of benign febrile seizures of childhood and describe the clinical and epidemiological profile of this population. This was a population-based, cross-sectional study, carried out in the city of Barra do Bugres, MT, Brazil, from August 2012 to August 2013. Data were collected in two phases. In the first phase, a questionnaire that was previously validated in another Brazilian study was used to identify suspected cases of seizures. In the second phase, a neurological evaluation was performed to confirm diagnosis. The prevalence was 6.4/1000 inhabitants (95% CI: 3.8-10.1). There was no difference between genders. Simple febrile seizures were found in 88.8% of cases. A family history of febrile seizures in first-degree relatives and history of epilepsy was present in 33.3% and 11.1% of patients, respectively. The prevalence of febrile seizures in Midwestern Brazil was lower than that found in other Brazilian regions, probably due to the inclusion only of febrile seizures with motor manifestations and differences in socioeconomic factors among the evaluated areas. Copyright © 2015 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Influence of language and ancestry on genetic structure of contiguous populations: A microsatellite based study on populations of Orissa

PubMed Central

Sahoo, Sanghamitra; Kashyap, VK

2005-01-01

Background We have examined genetic diversity at fifteen autosomal microsatellite loci in seven predominant populations of Orissa to decipher whether populations inhabiting the same geographic region can be differentiated on the basis of language or ancestry. The studied populations have diverse historical accounts of their origin, belong to two major ethnic groups and different linguistic families. Caucasoid caste populations are speakers of Indo-European language and comprise Brahmins, Khandayat, Karan and Gope, while the three Australoid tribal populations include two Austric speakers: Juang and Saora and a Dravidian speaking population, Paroja. These divergent groups provide a varied substratum for understanding variation of genetic patterns in a geographical area resulting from differential admixture between migrants groups and aboriginals, and the influence of this admixture on population stratification. Results The allele distribution pattern showed uniformity in the studied groups with approximately 81% genetic variability within populations. The coefficient of gene differentiation was found to be significantly higher in tribes (0.014) than caste groups (0.004). Genetic variance between the groups was 0.34% in both ethnic and linguistic clusters and statistically significant only in the ethnic apportionment. Although the populations were genetically close (FST = 0.010), the contemporary caste and tribal groups formed distinct clusters in both Principal-Component plot and Neighbor-Joining tree. In the phylogenetic tree, the Orissa Brahmins showed close affinity to populations of North India, while Khandayat and Gope clustered with the tribal groups, suggesting a possibility of their origin from indigenous people. Conclusions The extent of genetic differentiation in the contemporary caste and tribal groups of Orissa is highly significant and constitutes two distinct genetic clusters. Based on our observations, we suggest that since genetic distances and

Design of PREVENCION: a population-based study of cardiovascular disease in Peru.

PubMed

Medina-Lezama, Josefina; Chirinos, Julio A; Zea Díaz, Humberto; Morey, Oscar; Bolanos, Juan F; Munoz-Atahualpa, Edgar; Chirinos-Pacheco, Julio

2005-11-02

Latin America is undergoing the epidemiologic transition that occurred earlier in developed countries, and is likely to face a gigantic epidemic of heart disease in the next few years unless urgent action is taken. The first essential component of any effective cardiovascular disease (CVD) control program is to establish reliable estimates of cardiovascular disease-related morbidity and mortality. However, such data from population-based studies in Latin America are still lacking. In this paper, we present the design and operation of PREVENCION (Estudio Peruano de Prevalencia de Enfermedades Cardiovasculares, for Peruvian Study of the Prevalence of Cardiovascular diseases). PREVENCION is an ongoing population-based study on a representative sample of the civilian non-institutionalized population of the second largest city in Peru. Its population is comparable to the rest of the Peruvian urban population and closely resembles other Latin American populations in countries such as Bolivia and Ecuador. Our study will contribute to the enormous task of understanding and preventing CVD in Latin America.

Use of driving-impairing medicines by a Spanish population: a population-based registry study

PubMed Central

Gutierrez-Abejón, Eduardo; Herrera-Gómez, Francisco; Criado-Espegel, Paloma

2017-01-01

Objective To assess the use of driving-impairing medicines (DIM) in the general population with special reference to length of use and concomitant use. Design Population-based registry study. Setting The year 2015 granted medicines consumption data recorded in the Castile and León (Spain) medicine dispensation registry was consulted. Participants Medicines and DIM consumers from a Spanish population (Castile and León: 2.4 million inhabitants). Exposure Medicines and DIM consumption. Patterns of use by age and gender based on the length of use (acute: 1–7 days, subacute: 8–29 days and chronic use: ≥30 days) were of interest. Estimations regarding the distribution of licensed drivers by age and gender were employed to determine the patterns of use of DIM. Results DIM were consumed by 34.4% (95% CI 34.3% to 34.5%) of the general population in 2015, more commonly with regularity (chronic use: 22.5% vs acute use: 5.3%) and more frequently by the elderly. On average, 2.3 DIM per person were dispensed, particularly to chronic users (2.8 DIM per person). Age and gender distribution differences were observed between the Castile and León medicine dispensation registry data and the drivers’ license census data. Of all DIM dispensed, 83.8% were in the Anatomical Therapeutic Chemical code group nervous system medicines (N), which were prescribed to 29.2% of the population. Conclusions The use of DIM was frequent in the general population. Chronic use was common, but acute and subacute use should also be considered. This finding highlights the need to make patients, health professionals, health providers, medicine regulatory agencies and policy-makers at large aware of the role DIM play in traffic safety. PMID:29170289

Population-based study of presbyopia in Shahroud, Iran.

PubMed

Hashemi, Hassan; Khabazkhoob, Mehdi; Jafarzadehpur, Ebrahim; Mehravaran, Shiva; Emamian, Mohammad Hassan; Yekta, AbbasAli; Shariati, Mohammad; Fotouhi, Akbar

2012-12-01

There is limited information regarding the prevalence of presbyopia in different parts of the world. The add power and the prevalence of presbyopia by age and gender in general population of Shahroud, north of Iran, were studied. Population-based cross-sectional study. Using random cluster sampling, 6311 people from the 40- to 64-year-old population of Shahroud were invited. Of the invited population, 5190 individuals (82.2%) participated in the study. Presbyopia was defined as the correction of near vision to logMAR 1 (N8 point) with at least 1 D of add power. Near visual acuity of participants was evaluated with a logMAR chart at a distance of 40 cm. Mean add power in the age groups of 40-44, 45-49, 50-54, 55-59 and 60-64 years was 0.65, 1.30, 1.70, 1.87 and 2.08 D, respectively. For each 5-year increase in age, a 0.35 D increase in add power was noted. The prevalence of presbyopia was 58.15% (95% confidence interval: 56.46-59.84). Presbyopia was more prevalent in women (P < 0.001) and increased with ageing more in women than in men (P < 0.001). Furthermore, in the 60-64-year-old age group, 11% of men and 23% of women were not presbyopic. Compared with other reports, the add power in different age groups was 0.5 D less, and presbyopia was less prevalent. More than 50% of the over 45-year-old individuals were presbyopic and 17% of the over 60 individuals were free of this condition. © 2012 The Authors. Clinical and Experimental Ophthalmology © 2012 Royal Australian and New Zealand College of Ophthalmologists.

Wealth Inequality and Mental Disability Among the Chinese Population: A Population Based Study

PubMed Central

Wang, Zhenjie; Du, Wei; Pang, Lihua; Zhang, Lei; Chen, Gong; Zheng, Xiaoying

2015-01-01

In the study described herein, we investigated and explored the association between wealth inequality and the risk of mental disability in the Chinese population. We used nationally represented, population-based data from the second China National Sample Survey on Disability, conducted in 2006. A total of 1,724,398 study subjects between the ages of 15 and 64, including 10,095 subjects with mental disability only, were used for the analysis. Wealth status was estimated by a wealth index that was derived from a principal component analysis of 10 household assets and four other variables related to wealth. Logistic regression analysis was used to estimate the odds ratio (OR) and 95% confidence interval (CI) for mental disability for each category, with the lowest quintile category as the referent. Confounding variables under consideration were age, gender, residence area, marital status, ethnicity, education, current employment status, household size, house type, homeownership and living arrangement. The distribution of various types and severities of mental disability differed significantly by wealth index category in the present population. Wealth index category had a positive association with mild mental disability (p for trend <0.01), but had a negative association with extremely severe mental disability (p for trend <0.01). Moreover, wealth index category had a significant, inverse association with mental disability when all severities of mental disability were taken into consideration. This study’s results suggest that wealth is a significant factor in the distribution of mental disability and it might have different influences on various types and severities of mental disability. PMID:26492258

[Food and population: study of three countries].

PubMed

1988-12-01

In 1985, despite a nearly 25% worldwide surplus of cereals, more than 700 million poor people had insufficient food and some 17 million children died of malnutrition or related causes. 16% of the developing world's population is undernourished. Rapid population growth is a major reason for the world's hunger. Large families exhaust the resources of many urban couples and rural couples with little land. Closely spaced pregnancies deplete the nutritional resources of the mother and lead to low birth weight babies and inadequate lactation. Population growth in already densely populated countries reduces the land available for each family, inevitably contributing to poverty and rural malnutrition. Unemployment and underemployment reach alarming proportions in the city, where the combination of high fertility rates and migration from the countryside have produced growth twice that of the world population as a whole. Few developing countries have been able to generate sufficient investment to create new jobs for all seeking them. Unstable governments attempt to pacify urban unrest by subsidizing food prices and concentrating social and economic investments in the cities, causing further deterioration in rural conditions. Today more than 60 countries have food deficits, although not all are suffering. India, Kenya, and Mexico are 3 countries that have had some success in balancing population growth and food production, but each still has undernourished population sectors because of economic policies that fail to provide sufficient help to their poor and because of implacable population growth. Ending malnutrition in the 3 countries will require reducing the cost of food for households and increasing their incomes, but both objectives are made more difficult by rapid population growth. As a result of the green revolution and other factors, food production in India has tripled since 1950, but population has almost doubled in the same years. With rapid population growth, per

Predicting tuberculosis risk in the foreign-born population of British Columbia, Canada: study protocol for a retrospective population-based cohort study

PubMed Central

Ronald, Lisa A; Campbell, Jonathon R; Balshaw, Robert F; Roth, David Z; Romanowski, Kamila; Marra, Fawziah; Cook, Victoria J; Johnston, James C

2016-01-01

Introduction Improved understanding of risk factors for developing active tuberculosis (TB) will better inform decisions about diagnostic testing and treatment for latent TB infection (LTBI) in migrant populations in low-incidence regions. We aim to examine TB risk factors among the foreign-born population in British Columbia (BC), Canada, and to create and validate a clinically relevant multivariate risk score to predict active TB. Methods and analysis This retrospective population-based cohort study will include all foreign-born individuals who acquired permanent resident status in Canada between 1 January 1985 and 31 December 2013 and acquired healthcare coverage in BC at any point during this period. Multiple administrative databases and disease registries will be linked, including a National Immigration Database, BC Provincial Health Insurance Registration, physician billings, hospitalisations, drugs dispensed from community pharmacies, vital statistics, HIV testing and notifications, cancer, chronic kidney disease and dialysis treatment, and all TB and LTBI testing and treatment data in BC. Extended proportional hazards regression will be used to estimate risk factors for TB and to create a prognostic TB risk score. Ethics and dissemination Ethical approval for this study has been obtained from the University of British Columbia Clinical Ethics Review Board. Once completed, study findings will be presented at conferences and published in peer-reviewed journals. An online TB risk score calculator will also be created. PMID:27888179

Medical Genetics and the First Studies of the Genetics of Populations in Mexico

PubMed Central

Barahona, Ana

2016-01-01

Following World War II (WWII), there was a new emphasis within genetics on studying the genetic composition of populations. This probably had a dual source in the growing strength of evolutionary biology and the new international interest in understanding the effects of radiation on human populations, following the atomic bombings in Japan. These global concerns were shared by Mexican physicians. Indeed, Mexico was one of the leading centers of this trend in human genetics. Three leading players in this story were Mario Salazar Mallén, Adolfo Karl, and Rubén Lisker. Their trajectories and the international networks in human genetics that were established after WWII, paved the way for the establishment of medical and population genetics in Mexico. Salazar Mallén’s studies on the distribution and characterization of ABO blood groups in indigenous populations were the starting point while Karl’s studies on the distribution of abnormal hemoglobin in Mexican indigenous populations showed the relationships observed in other laboratories at the time. It was Lisker’s studies, however, that were instrumental in the development of population genetics in the context of national public policies for extending health care services to the Mexican population. In particular, he conducted studies on Mexican indigenous groups contributing to the knowledge of the biological diversity of human populations according to international trends that focused on the variability of human populations in terms of genetic frequencies. From the start, however, Lisker was as committed to the reconstruction of shared languages and practices as he was to building networks of collaboration in order to guarantee the necessary groundwork for establishing the study of the genetics of human populations in Mexico. This study also allows us to place Mexican science within a global context in which connected narratives describe the interplay between global trends and national contexts. PMID:27601615

Medical Genetics and the First Studies of the Genetics of Populations in Mexico.

PubMed

Barahona, Ana

2016-09-01

Following World War II (WWII), there was a new emphasis within genetics on studying the genetic composition of populations. This probably had a dual source in the growing strength of evolutionary biology and the new international interest in understanding the effects of radiation on human populations, following the atomic bombings in Japan. These global concerns were shared by Mexican physicians. Indeed, Mexico was one of the leading centers of this trend in human genetics. Three leading players in this story were Mario Salazar Mallén, Adolfo Karl, and Rubén Lisker. Their trajectories and the international networks in human genetics that were established after WWII, paved the way for the establishment of medical and population genetics in Mexico. Salazar Mallén's studies on the distribution and characterization of ABO blood groups in indigenous populations were the starting point while Karl's studies on the distribution of abnormal hemoglobin in Mexican indigenous populations showed the relationships observed in other laboratories at the time. It was Lisker's studies, however, that were instrumental in the development of population genetics in the context of national public policies for extending health care services to the Mexican population. In particular, he conducted studies on Mexican indigenous groups contributing to the knowledge of the biological diversity of human populations according to international trends that focused on the variability of human populations in terms of genetic frequencies. From the start, however, Lisker was as committed to the reconstruction of shared languages and practices as he was to building networks of collaboration in order to guarantee the necessary groundwork for establishing the study of the genetics of human populations in Mexico. This study also allows us to place Mexican science within a global context in which connected narratives describe the interplay between global trends and national contexts. Copyright © 2016 by

Population genetic study in ten endogamous groups of West Bengal, India.

PubMed

Mukherjee, B N; Walter, H; Malhotra, K C; Chakraborty, R; Sauber, P; Banerjee, S; Roy, M

1987-09-01

Ten endogamous population groups of West Bengal (India)--Rabhas, Garos, Mechs, Rajbanshis, Jalia Kaibartas, Bagdis, Lodhas, Mundas, Brahmins, Vaidyas--have been typed for twelve polymorphic systems: ABO, Gm, Km, Hp, Cp, Tf, Alb, Hb, aP, EsD, AK and PGM1. The results are compared with those obtained on other Indian populations. Serological and anthropometric data, which have been included into population comparisons, reveal a considerable genetic variability of the groups under study. This variability is obviously connected with the population history of West Bengal.

Succession of Pelagic Organisms in the Size Range 0·5-200 μm During a Diatom Bloom in Otsuchi Bay, Japan

NASA Astrophysics Data System (ADS)

Tsuda, Atsushi; Sugisaki, Hiroya; Takahashi, Koji; Furuya, Ken

1994-08-01

The succession of pelagic organisms in the approximate size range 0·5-200 μm was investigated during a spring diatom bloom in Otsuchi Bay on the Pacific coast of northern Japan. The diatom bloom lasted 3 weeks in the middle of the period examined. The study period was divided into three phases: pre-bloom, bloom and post-bloom. Mesodinium rubrum, an autotrophic ciliate, was abundant in the pre-bloom phase, when vertical mixing was intense. During the bloom phase, the biomass of organisms other than diatoms themselves and bacteria was depressed. A bacterial peak was observed 4 days after the diatom peak and peaks of nano-autotrophs and -heterotrophs occurred after 14 days. Phototrophic picoplankton showed a biomass peak at the same time as nanoplankton. Grazing on diatoms by the copepod population was shown by the occurrences of faecal pellets and copepod nauplii during and after the bloom phase. These results suggest that production of copepods and bacteria depended only on the diatom bloom directly, and that heterotrophic micro-protista depended on the production of pico- and nano-autotrophs in the post-bloom phase.

The study to estimate the floating population in Seoul, Korea.

PubMed

Lee, Geon Woo; Lee, Yong Jin; Kim, Youngeun; Hong, Seung-Han; Kim, Soohwaun; Kim, Jeong Soo; Lee, Jong Tae; Shin, Dong Chun; Lim, Youngwook

2017-01-01

Traffic-related pollutants have been reported to increase the morbidity of respiratory diseases. In order to apply management policies related to motor vehicles, studies of the floating population living in cities are important. The rate of metro rail transit system use by passengers residing in Seoul is about 54% of total public transportation use. Through the rate of metro use, the people-flow ratios in each administrative area were calculated. By applying a people-flow ratio based on the official census count, the floating population in 25 regions was calculated. The reduced level of deaths among the floating population in 14 regions having the roadside monitoring station was calculated as assuming a 20% reduction of mobile emission based on the policy. The hourly floating population size was calculated by applying the hourly population ratio to the regional population size as specified in the official census count. The number of people moving from 5 a.m. to next day 1 a.m. could not be precisely calculated when the population size was applied, but no issue was observed that would trigger a sizable shift in the rate of population change. The three patterns of increase, decrease, and no change of population in work hours were analyzed. When the concentration of particulate matter less than 10 μm in aerodynamic diameter was reduced by 20%, the number of excess deaths varied according to the difference of the floating population. The effective establishment of directions to manage the pollutants in cities should be carried out by considering the floating population. Although the number of people using the metro system is only an estimate, this disadvantage was supplemented by calculating inflow and outflow ratio of metro users per time in the total floating population in each region. Especially, 54% of metro usage in public transport causes high reliability in application.

Consequences of population topology for studying gene flow using link-based landscape genetic methods.

PubMed

van Strien, Maarten J

2017-07-01

Many landscape genetic studies aim to determine the effect of landscape on gene flow between populations. These studies frequently employ link-based methods that relate pairwise measures of historical gene flow to measures of the landscape and the geographical distance between populations. However, apart from landscape and distance, there is a third important factor that can influence historical gene flow, that is, population topology (i.e., the arrangement of populations throughout a landscape). As the population topology is determined in part by the landscape configuration, I argue that it should play a more prominent role in landscape genetics. Making use of existing literature and theoretical examples, I discuss how population topology can influence results in landscape genetic studies and how it can be taken into account to improve the accuracy of these results. In support of my arguments, I have performed a literature review of landscape genetic studies published during the first half of 2015 as well as several computer simulations of gene flow between populations. First, I argue why one should carefully consider which population pairs should be included in link-based analyses. Second, I discuss several ways in which the population topology can be incorporated in response and explanatory variables. Third, I outline why it is important to sample populations in such a way that a good representation of the population topology is obtained. Fourth, I discuss how statistical testing for link-based approaches could be influenced by the population topology. I conclude the article with six recommendations geared toward better incorporating population topology in link-based landscape genetic studies.

A dynamic urban air pollution population exposure assessment study using model and population density data derived by mobile phone traffic

NASA Astrophysics Data System (ADS)

Gariazzo, Claudio; Pelliccioni, Armando; Bolignano, Andrea

2016-04-01

A dynamic city-wide air pollution exposure assessment study has been carried out for the urban population of Rome, Italy, by using time resolved population distribution maps, derived by mobile phone traffic data, and modelled air pollutants (NO2, O3 and PM2.5) concentrations obtained by an integrated air dispersion modelling system. More than a million of persons were tracked during two months (March and April 2015) for their position within the city and its surroundings areas, with a time resolution of 15 min and mapped over an irregular grid system with a minimum resolution of 0.26 × 0.34 Km2. In addition, demographics information (as gender and age ranges) were available in a separated dataset not connected with the total population one. Such BigData were matched in time and space with air pollution model results and then used to produce hourly and daily resolved cumulative population exposures during the studied period. A significant mobility of population was identified with higher population densities in downtown areas during daytime increasing of up to 1000 people/Km2 with respect to nigh-time one, likely produced by commuters, tourists and working age population. Strong variability (up to ±50% for NO2) of population exposures were detected as an effect of both mobility and time/spatial changing in pollutants concentrations. A comparison with the correspondent stationary approach based on National Census data, allows detecting the inability of latter in estimating the actual variability of population exposure. Significant underestimations of the amount of population exposed to daily PM2.5 WHO guideline was identified for the Census approach. Very small differences (up to a few μg/m3) on exposure were detected for gender and age ranges population classes.

[Psychiatric comorbidities in transsexualism: Study of a Lebanese transgender population].

PubMed

Ibrahim, C; Haddad, R; Richa, S

2016-12-01

The question of whether gender dysphoria is associated with psychiatric comorbidity has been addressed in several studies. Several cohort studies have shown that psychiatric comorbidity is one of the main features of poor prognosis following sex change therapy. Gender dysphoria is rare, with an estimated prevalence of 0.001% to 0.002% globally. The literature shows a high prevalence of psychiatric comorbidities in people with gender dysphoria, and that they are more common in male to female transsexuals. Data on long-term mortality show that transsexuals present a 51 % increase in mortality compared to the general population. This is mainly attributed to a six-fold increase in the number of suicides and a higher rate of psychiatric disorders and risky behaviors leading to HIV infection and substance abuse. Assess psychiatric comorbidity in a population of Lebanese transgender individuals and compare it to the general population. The hypothesis of our study is that the Lebanese transgenders suffer from more psychiatric comorbidities than the general population. Our second objective was to determine the specific mental health needs of this population in order to adapt our services to their medical needs and their specific concerns. Our objective was to acquire 20 transgender participants and 20 control subjects. We chose a snowball sampling method. The evaluation consisted of three questionnaires including a general demographic questionnaire, the MINI 5.0.0 Arabic version for axis I disorders and the SCID-II for axis II disorders. The mean age of both groups was 23.55 years. Fifty-five percent (n=11) transgender participants had active suicidal thoughts against 0 % in controls. Within the group of transgender, 45 % (n=9) had a major depressive episode, 5 % (n=1) had a generalized anxiety disorder, 5 % (n=1) had a posttraumatic stress disorder and 10 % (n=2) had a major depressive episode with comorbid posttraumatic stress disorder. We noted a significant

Our World of 7 Billion: Population Studies in Today's Social Studies Classroom

ERIC Educational Resources Information Center

Wasserman, Pamela

2011-01-01

The study of world population integrates so many themes and disciplines in the social studies because it encompasses all of human history--the rise of agriculture and civilizations, scientific progress, territorial conflicts, changing gender roles and more. It is also at the heart of human geography and how people came to dominate and alter the…

Considering population and war: a critical and neglected aspect of conflict studies

PubMed Central

Thayer, Bradley A.

2009-01-01

This study analyses the relationship between war and population. The impact of the growth and decline of population on important types of warfare—great power, small power, civil war as well as terrorism—is illustrated, with the objective in each case to be descriptive of risk. I find that population change has a significant impact on each, with the greatest causal impact on small power conflicts, civil war and upon terrorism. I conclude with some reasons for guarded optimism about the incorporation of population as a component of analysis in the discipline of international studies, and for the potential to devise new solutions to prevent conflict. PMID:19770157

Epidemiology of uveitis among the Chinese population in Taiwan: a population-based study.

PubMed

Hwang, De-Kuang; Chou, Yiing-Jeng; Pu, Cheng-Yun; Chou, Pesus

2012-11-01

This study aimed to investigate the incidence and prevalence of uveitis in Taiwan, and then analyzed the risk factors related to uveitis using multivariate regression. Population-based cohort study using medical claims data. We randomly selected 1 000 000 residents from the Taiwan National Health Insurance Research Database. All participants with correct registry data (96%) were included in the study. The study period was from 2000 to 2008. All types of uveitis were identified using the International Classification of Diseases, 9th revision, Clinical Modification diagnostic codes. The annual incidence and cumulative prevalence of uveitis were calculated. A univariate and a multivariate Poisson regression were used to determine the risk factors associated with uveitis. The first diagnosis of uveitis noted during the study period. The annual cumulative incidence rate of uveitis ranged from 102.2 to 122.0 cases per 100 000 persons over the study period, and the average incidence density was 111.3 cases per 100 000 person-years (95% confidence interval, 108.4-114.1). The cumulative prevalence was found to have increased from 318.8 cases per 100 000 persons in 2003 to 622.7 cases per 100 000 persons in 2008. Anterior uveitis was the most common location and accounted for 77.7% of all incident cases, which was followed by panuveitis, posterior uveitis, and intermediate uveitis. Multivariate regression analysis showed that males, the elderly, and individuals who lived in an urban area had higher incidence rates for uveitis. The epidemiology of uveitis in Taiwan differs from most previous studies in other countries. The incidence of uveitis in Taiwan has increased significantly recently. The elderly and individuals living in urban areas are the populations that are most commonly affected by uveitis. These findings are consistent with suggestions found in several recent studies. Copyright © 2012 American Academy of Ophthalmology. Published by Elsevier Inc. All rights

Nationwide Genomic Study in Denmark Reveals Remarkable Population Homogeneity

PubMed Central

Athanasiadis, Georgios; Cheng, Jade Y.; Vilhjálmsson, Bjarni J.; Jørgensen, Frank G.; Als, Thomas D.; Le Hellard, Stephanie; Espeseth, Thomas; Sullivan, Patrick F.; Hultman, Christina M.; Kjærgaard, Peter C.; Schierup, Mikkel H.; Mailund, Thomas

2016-01-01

Denmark has played a substantial role in the history of Northern Europe. Through a nationwide scientific outreach initiative, we collected genetic and anthropometrical data from ∼800 high school students and used them to elucidate the genetic makeup of the Danish population, as well as to assess polygenic predictions of phenotypic traits in adolescents. We observed remarkable homogeneity across different geographic regions, although we could still detect weak signals of genetic structure reflecting the history of the country. Denmark presented genomic affinity with primarily neighboring countries with overall resemblance of decreasing weight from Britain, Sweden, Norway, Germany, and France. A Polish admixture signal was detected in Zealand and Funen, and our date estimates coincided with historical evidence of Wend settlements in the south of Denmark. We also observed considerably diverse demographic histories among Scandinavian countries, with Denmark having the smallest current effective population size compared to Norway and Sweden. Finally, we found that polygenic prediction of self-reported adolescent height in the population was remarkably accurate (R2 = 0.639 ± 0.015). The high homogeneity of the Danish population could render population structure a lesser concern for the upcoming large-scale gene-mapping studies in the country. PMID:27535931

Population Projection. Applications of Linear Algebra to Population Studies. Modules and Monographs in Undergraduate Mathematics and Its Applications. UMAP Module 345.

ERIC Educational Resources Information Center

Keller, Edward L.

This unit, which looks at applications of linear algebra to population studies, is designed to help pupils: (1) understand an application of matrix algebra to the study of populations; (2) see how knowledge of eigen values and eigen vectors is useful in studying powers of matrices; and (3) be briefly exposed to some difficult but interesting…

Occupational risk and chronic kidney disease: a population-based study in the United States adult population.

PubMed

Rubinstein, Sofia; Wang, Chengwei; Qu, Wenchun

2013-01-01

Previous studies on occupational risk for chronic kidney disease (CKD) have analyzed a limited range of occupations and focused on nephrotoxins. The primary purpose of this study was to examine the relative risk for the occurrence of CKD between different occupations in the US adult population. This was a population-based survey study of 91,340 participants in the US, who completed the National Health Interview Survey, 2004 through 2008. The outcome variable, CKD, was defined as having weakening/failing kidneys in the past 12 months, as diagnosed by a physician. The predictor variable, occupation, was obtained using the census occupational codes, regrouped according to North American Industrial Classification System. After controlling for age, gender, hypertension, and education, and with the category Life, Physical, and Social Science Occupations as a reference group, the likelihood of developing CKD was 4.3 times higher in respondents working in Building, Grounds Cleaning and Maintenance Occupations, 4.4 times higher in Healthcare Practitioners and Technical Occupations, 4.7 times higher in Transportation and Material Moving Occupations and in Computer and Mathematical Occupations, 4.8 times higher in Production Occupations, 5.3 times higher in Food Preparation and Serving Related Occupations, and 6.1 times higher in Healthcare Support Occupations and in Legal Occupations. This study identified occupation groups in US adult population with increased risk for CKD. Alleviation of workplace stress is suggested as a goal for behavioral intervention in high-risk occupations.

VISIT-TS: A multimedia tool for population studies on tic disorders.

PubMed

Vachon, M Jonathan; Striley, Catherine W; Gordon, Mollie R; Schroeder, Miriam L; Bihun, Emily C; Koller, Jonathan M; Black, Kevin J

2016-01-01

Population-based assessment of Tourette syndrome (TS) and other tic disorders produces a paradox. On one hand, ideally diagnosis of tic disorders requires expert observation. In fact, diagnostic criteria for TS explicitly require expert assessment of tics for a definite diagnosis. On the other hand, large-scale population surveys with expert assessment of every subject are impracticable. True, several published studies have successfully used expert assessment to find tic prevalence in a representative population (e.g. all students in a school district). However, extending these studies to larger populations is daunting. We created a multimedia tool to demonstrate tics to a lay audience, discuss their defining and common attributes, and address features that differentiate tics from other movements and vocalizations. A first version was modified to improve clarity and to include a more diverse group in terms of age and ethnicity. The result is a tool intended for epidemiological research. It may also provide additional benefits, such as more representative minority recruitment for other TS studies and increased community awareness of TS.

Genetic affinities of north and northeastern populations of India: inference from HLA-based study.

PubMed

Agrawal, S; Srivastava, S K; Borkar, M; Chaudhuri, T K

2008-08-01

India is like a microcosm of the world in terms of its diversity; religion, climate and ethnicity which leads to genetic variations in the populations. As a highly polymorphic marker, the human leukocyte antigen (HLA) system plays an important role in the genetic differentiation studies. To assess the genetic diversity of HLA class II loci, we studied a total of 1336 individuals from north India using DNA-based techniques. The study included four endogamous castes (Kayastha, Mathurs, Rastogies and Vaishyas), two inbreeding Muslim populations (Shias and Sunnis) from north India and three northeast Indian populations (Lachung, Mech and Rajbanshi). A total of 36 alleles were observed at DRB1 locus in both Hindu castes and Muslims from north, while 21 alleles were seen in northeast Indians. At the DQA1 locus, the number of alleles ranged from 11 to 17 in the studied populations. The total number of alleles at DQB1 was 19, 12 and 20 in the studied castes, Muslims and northeastern populations, respectively. The most frequent haplotypes observed in all the studied populations were DRB1*0701-DQA1*0201-DQB1*0201 and DRB1*1501-DQA1*0103-DQB1*0601. Upon comparing our results with other world populations, we observed the presence of Caucasoid element in north Indian population. However, differential admixturing among Sunnis and Shias with the other north Indians was evident. Northeastern populations showed genetic affinity with Mongoloids from southeast Asia. When genetic distances were calculated, we found the north Indians and northeastern populations to be markedly unrelated.

DEMOGRAPHIC CHARACTERISTICS OF THE NHEXAS-ARIZONA BORDER STUDY POPULATION

EPA Science Inventory

The NHEXAS-Arizona Border Study employed a population based probability design to recruit a representative cohort residing within 40 Km of the US-Mexico Border in Arizona. As an extension of the NHEXAS Arizona statewide survey, the border study was designed to determine the dis...

Health examination utilization in the visually disabled population in Taiwan: a nationwide population-based study

PubMed Central

2013-01-01

Background People with visual disabilities have increased health needs but face worse inequity to preventive health examinations. To date, only a few nationwide studies have analyzed the utilization of preventive adult health examinations by the visually disabled population. The aim of this study was to investigate the utilization of health examinations by the visually disabled population, and analyze the factors associated with the utilization. Methods Visual disability was certified by ophthalmologists and authenticated by the Ministry of the Interior (MOI), Taiwan. We linked data from three different nationwide datasets (from the MOI, Bureau of Health Promotion, and National Health Research Institutes) between 2006 and 2008 as the data sources. Independent variables included demographic characteristics, income status, health status, and severity of disability; health examination utilization status was the dependent variable. The chi-square test was used to check statistical differences between variables, and a multivariate logistic regression model was used to examine the associated factors with health examination utilization. Results In total, 47,812 visually disabled subjects aged 40 years and over were included in this study, only 16.6% of whom received a health examination. Lower utilization was more likely in male subjects, in those aged 65 years and above, insured dependents and those with a top-ranked premium-based salary, catastrophic illness/injury, chronic diseases of the genitourinary system, and severe or very severe disabilities. Conclusion The overall health examination utilization in the visually disabled population was very low. Lower utilization occurred mainly in males, the elderly, and those with severe disabilities. PMID:24313981

Predicting tuberculosis risk in the foreign-born population of British Columbia, Canada: study protocol for a retrospective population-based cohort study.

PubMed

Ronald, Lisa A; Campbell, Jonathon R; Balshaw, Robert F; Roth, David Z; Romanowski, Kamila; Marra, Fawziah; Cook, Victoria J; Johnston, James C

2016-11-25

Improved understanding of risk factors for developing active tuberculosis (TB) will better inform decisions about diagnostic testing and treatment for latent TB infection (LTBI) in migrant populations in low-incidence regions. We aim to examine TB risk factors among the foreign-born population in British Columbia (BC), Canada, and to create and validate a clinically relevant multivariate risk score to predict active TB. This retrospective population-based cohort study will include all foreign-born individuals who acquired permanent resident status in Canada between 1 January 1985 and 31 December 2013 and acquired healthcare coverage in BC at any point during this period. Multiple administrative databases and disease registries will be linked, including a National Immigration Database, BC Provincial Health Insurance Registration, physician billings, hospitalisations, drugs dispensed from community pharmacies, vital statistics, HIV testing and notifications, cancer, chronic kidney disease and dialysis treatment, and all TB and LTBI testing and treatment data in BC. Extended proportional hazards regression will be used to estimate risk factors for TB and to create a prognostic TB risk score. Ethical approval for this study has been obtained from the University of British Columbia Clinical Ethics Review Board. Once completed, study findings will be presented at conferences and published in peer-reviewed journals. An online TB risk score calculator will also be created. 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/.

Binaries, cluster dynamics and population studies of stars and stellar phenomena

NASA Astrophysics Data System (ADS)

Vanbeveren, Dany

2005-10-01

The effects of binaries on population studies of stars and stellar phenomena have been investigated over the past 3 decades by many research groups. Here we will focus mainly on the work that has been done recently in Brussels and we will consider the following topics: the effect of binaries on overall galactic chemical evolutionary models and on the rates of different types of supernova, the population of point-like X-ray sources where we distinguish the standard high mass X-ray binaries and the ULXs, a UFO-scenario for the formation of WR+OB binaries in dense star systems. Finally we critically discuss the possible effect of rotation on population studies.

EFFECTS OF CHRONIC STRESS ON WILDLIFE POPULATIONS: A POPULATION MODELING APPROACH AND CASE STUDY

EPA Science Inventory

This chapter describes a matrix modeling approach to characterize and project risks to wildlife populations subject to chronic stress. Population matrix modeling was used to estimate effects of one class of environmental contaminants, dioxin-like compounds (DLCs), to populations ...

Radiation belt seed population and its association with the relativistic electron dynamics: A statistical study: Radiation Belt Seed Population

DOE PAGES

Tang, C. L.; Wang, Y. X.; Ni, B.; ...

2017-05-19

Using the Van Allen Probes data, we study the radiation belt seed population and it associated with the relativistic electron dynamics during 74 geomagnetic storm events. Based on the flux changes of 1 MeV electrons before and after the storm peak, these storm events are divided into two groups of “non-preconditioned” and “preconditioned”. The statistical study shows that the storm intensity is of significant importance for the distribution of the seed population (336 keV electrons) in the outer radiation belt. However, substorm intensity can also be important to the evolution of the seed population for some geomagnetic storm events. Formore » non-preconditioned storm events, the correlation between the peak fluxes and their L-shell locations of the seed population and relativistic electrons (592 keV, 1.0 MeV, 1.8 MeV, and 2.1 MeV) is consistent with the energy-dependent dynamic processes in the outer radiation belt. For preconditioned storm events, the correlation between the features of the seed population and relativistic electrons is not fully consistent with the energy-dependent processes. It is suggested that the good correlation between the radiation belt seed population and ≤1.0 MeV electrons contributes to the prediction of the evolution of ≤1.0 MeV electrons in the Earth’s outer radiation belt during periods of geomagnetic storms.« less

Radiation belt seed population and its association with the relativistic electron dynamics: A statistical study: Radiation Belt Seed Population

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

Tang, C. L.; Wang, Y. X.; Ni, B.

Using the Van Allen Probes data, we study the radiation belt seed population and it associated with the relativistic electron dynamics during 74 geomagnetic storm events. Based on the flux changes of 1 MeV electrons before and after the storm peak, these storm events are divided into two groups of “non-preconditioned” and “preconditioned”. The statistical study shows that the storm intensity is of significant importance for the distribution of the seed population (336 keV electrons) in the outer radiation belt. However, substorm intensity can also be important to the evolution of the seed population for some geomagnetic storm events. Formore » non-preconditioned storm events, the correlation between the peak fluxes and their L-shell locations of the seed population and relativistic electrons (592 keV, 1.0 MeV, 1.8 MeV, and 2.1 MeV) is consistent with the energy-dependent dynamic processes in the outer radiation belt. For preconditioned storm events, the correlation between the features of the seed population and relativistic electrons is not fully consistent with the energy-dependent processes. It is suggested that the good correlation between the radiation belt seed population and ≤1.0 MeV electrons contributes to the prediction of the evolution of ≤1.0 MeV electrons in the Earth’s outer radiation belt during periods of geomagnetic storms.« less

Incidence of Parkinson's disease and atypical parkinsonism: Russian population-based study.

PubMed

Winter, Yaroslav; Bezdolnyy, Yury; Katunina, Elena; Avakjan, Gagik; Reese, Jens P; Klotsche, Jens; Oertel, Wolfgang H; Dodel, Richard; Gusev, Eugene

2010-02-15

Data on the incidence of Parkinson's disease (PD) and atypical parkinsonian syndromes (APS) in East European countries and Asia are limited. The objective of this prospective population-based study was to determine the incidence of PD and APS in the Russian population. The study area was a large district of Moscow with a population of 1,237,900 inhabitants. Multiple sources of case ascertainment were used to identify incident cases of PD and APS between July 2006 and December 2008. All incident cases were examined by a specialist and followed up prospectively to confirm the diagnosis. The age-standardized incidence rates per 100,000/year were 9.03 [95% confidence interval (CI) 8.01-10.15] for PD, 0.11 (95% CI 0.03-0.23) for multiple system atrophy, 0.14 (95% CI 0.08-0.21) for progressive supranuclear palsy, and 0.02 (95% CI 0.01-0.12) for corticobasal degeneration. The age-standardized male-to-female ratio of PD was 0.87 for all ages and 1.46 for those aged 60 and older. A high proportion of new cases with PD (34%) and APS (50%) had comorbid depressive symptoms. Given the rapid growth of the elderly population in Eastern Europe and Asia, the epidemiology of PD and APS in these regions should be investigated in greater depth. The incidence of PD in our study was slightly lower than in studies of Western populations and the male-to-female ratio was closer to those reported in studies from Asia. The clinical implication of our study is that it highlights the need for better diagnosis and treatment of depression in early stages of PD. (c) 2010 Movement Disorder Society.

A Population Synthesis Study of Terrestrial Gamma-ray Flashes

NASA Astrophysics Data System (ADS)

Cramer, E. S.; Briggs, M. S.; Stanbro, M.; Dwyer, J. R.; Mailyan, B. G.; Roberts, O.

2017-12-01

In astrophysics, population synthesis models are tools used to determine what mix of stars could be consistent with the observations, e.g. how the intrinsic mass-to-light ratio changes by the measurement process. A similar technique could be used to understand the production of TGFs. The models used for this type of population study probe the conditions of electron acceleration inside the high electric field regions of thunderstorms, i.e. acceleration length, electric field strength, and beaming angles. In this work, we use a Monte Carlo code to generate bremsstrahlung photons from relativistic electrons that are accelerated by a large-scale RREA thunderstorm electric field. The code simulates the propagation of photons through the atmosphere at various source altitudes, where they interact with air via Compton scattering, pair production, and photoelectric absorption. We then show the differences in the hardness ratio at spacecraft altitude between these different simulations and compare them with TGF data from Fermi-GBM. Such comparisons can lead to constraints that can be applied to popular TGF beaming models, and help determine whether the population presented in this study is consistent or not with reality.

Risk factors associated with endometriosis: importance of study population for characterizing disease in the ENDO Study

PubMed Central

Peterson, C. Matthew; Johnstone, Erica B.; Hammoud, Ahmad O.; Stanford, Joseph B.; Varner, Michael W.; Kennedy, Anne; Chen, Zhen; Sun, Liping; Fujimoto, Victor Y.; Hediger, Mary L.; Buck Louis, Germaine M.

2014-01-01

OBJECTIVE We sought to identify risk factors for endometriosis and their consistency across study populations in the Endometriosis: Natural History, Diagnosis, and Outcomes (ENDO) Study. STUDY DESIGN In this prospective matched, exposure cohort design, 495 women aged 18–44 years undergoing pelvic surgery (exposed to surgery, operative cohort) were compared to an age- and residence-matched population cohort of 131 women (unexposed to surgery, populationcohort). Endometriosis was diagnosed visually at laparoscopy/laparotomy or by pelvic magnetic resonance imaging in the operative and population cohorts, respectively. Logistic regression estimated the adjusted odds ratios (AORs) and 95% confidence intervals (CIs) for each cohort. RESULTS The incidence of visualized endometriosis was 40% in the operative cohort (11.8% stage 3–4 by revised criteria from the American Society for Reproductive Medicine), and 11% stage 3–4 in the population cohort by magnetic resonance imaging. An infertility history increased the odds of an endometriosis diagnosis in both the operative (AOR, 2.43; 95% CI, 1.57–3.76) and population (AOR, 7.91; 95% CI, 1.69–37.2) cohorts. In the operative cohort only, dysmenorrhea (AOR, 2.46; 95% CI, 1.28–4.72) and pelvic pain (AOR, 3.67; 95% CI, 2.44–5.50) increased the odds of diagnosis, while gravidity (AOR, 0.49; 95% CI, 0.32–0.75), parity (AOR, 0.42; 95% CI, 0.28–0.64), and body mass index (AOR, 0.95; 95% CI, 0.93–0.98) decreased the odds of diagnosis. In all sensitivity analyses for different diagnostic subgroups, infertility history remained a strong risk factor. CONCLUSION An infertility history was a consistent risk factor for endometriosis in both the operative and population cohorts of the ENDO Study. Additionally, identified risk factors for endometriosis vary based upon cohort selection and diagnostic accuracy. Finally, endometriosis in the population may be more common than recognized. PMID:23454253

Seroprevalence of Toxocariasis in Children with Urticaria: A Population-based Study.

PubMed

Matos Fialho, Paula Mayara; Correa, Carlos Roberto Silveira; Lescano, Susana Zevallos

2017-10-01

This study described the prevalence of IgG class antibodies against Toxocara spp. and their association with urticaria in 2- to 12-year-old children. This population-based cross-sectional study was conducted between May 2012 and September 2014. The study sample comprised 168 children. Blood samples were collected to verify the presence of toxocariasis by using ELISA to detect IgG antibodies. The guardians of the children were interviewed to characterize the presence or absence of other diseases, such as urticaria. The presence of urticaria was observed in 38% of participants. The seroprevalence of toxocariasis in this population was 16%. This study confirmed a positive association between urticaria and positive serology for Toxocara and a negative independent association with canine contact and the number of household residents. There are no previous reports in the literature of a population-based study that correlates the presence of urticaria with serology for toxocariasis. © The Author [2017]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Census data for studying elderly populations.

PubMed

Martin, L G

1987-06-01

As fertility and population growth rates decline in the Asian and Pacific region, populations of the elderly (aged 65 and older) are growing rapidly. In 1980, the number of elderly was roughly equally divided between more developed and less developed countries; in the future, the majority of the elderly will live in less developed countries, especially in Asia. Most countries will double their elderly populations between 1980 and 2000. Censuses can provide information for planning ways to accommodate the growing numbers of elderly. Most censuses in the Asian and Pacific region provide population counts to fairly high ages. The elderly should not be stereotyped by assuming that they are all alike physically, emotionally, socially, and politically. Except for Indonesia and the Republic of Korea, all the censuses lower the last age for which provide detail in their published tabulations of marital status data compared to tabulations of population counts. Policy makers are more concerned with the extent to which the generations live together. Censuses potentially are a rich source of data on living arrangements, but, except for Japan, that potential is not being realized. Various types of information on the living arrangements of the elderly are contained in several censuses. An example is tabulations by 5-year groups to 85+ years of individuals by their relationship to the household head and by family type. It is important for the government to ascertain the extent to which some elderly may need some public assistance. Most of the censuses provide information on labor force participation to ages 60 or 65 and above. Censuses also provide information on income. More information will be needed on elderly in the future and much of it can be made available by increasing the amount of detail, by age, in published tabulations. Censuses can provide a regular, reliable flow of data and information that will form the foundation for designing programs for the expanding elderly

77 FR 70451 - Proposed Collection; Comment Request; Methodological Studies for the Population Assessment of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-26

... Request; Methodological Studies for the Population Assessment of Tobacco and Health (PATH) Study SUMMARY... Collection: Title: Methodological Studies for Population Assessment of Tobacco and Health (PATH) Study. Type... methodological studies to improve the PATH study instrumentation and data collection procedures. These...

The HealthNuts population-based study of paediatric food allergy: validity, safety and acceptability.

PubMed

Osborne, N J; Koplin, J J; Martin, P E; Gurrin, L C; Thiele, L; Tang, M L; Ponsonby, A-L; Dharmage, S C; Allen, K J

2010-10-01

The incidence of hospital admissions for food allergy-related anaphylaxis in Australia has increased, in line with world-wide trends. However, a valid measure of food allergy prevalence and risk factor data from a population-based study is still lacking. To describe the study design and methods used to recruit infants from a population for skin prick testing and oral food challenges, and the use of preliminary data to investigate the extent to which the study sample is representative of the target population. The study sampling frame design comprises 12-month-old infants presenting for routine scheduled vaccination at immunization clinics in Melbourne, Australia. We compared demographic features of participating families to population summary statistics from the Victorian Perinatal census database, and administered a survey to those non-responders who chose not to participate in the study. Study design proved acceptable to the community with good uptake (response rate 73.4%), with 2171 participants recruited. Demographic information on the study population mirrored the Victorian population with most the population parameters measured falling within our confidence intervals (CI). Use of a non-responder questionnaire revealed that a higher proportion of infants who declined to participate (non-responders) were already eating and tolerating peanuts, than those agreeing to participate (54.4%; 95% CI 50.8, 58.0 vs. 27.4%; 95% CI 25.5, 29.3 among participants). A high proportion of individuals approached in a community setting participated in a food allergy study. The study population differed from the eligible sample in relation to family history of allergy and prior consumption and peanut tolerance, providing some insights into the internal validity of the sample. The study exhibited external validity on general demographics to all births in Victoria. © 2010 Blackwell Publishing Ltd.

Population specific biomarkers of human aging: a big data study using South Korean, Canadian and Eastern European patient populations.

PubMed

Mamoshina, Polina; Kochetov, Kirill; Putin, Evgeny; Cortese, Franco; Aliper, Alexander; Lee, Won-Suk; Ahn, Sung-Min; Uhn, Lee; Skjodt, Neil; Kovalchuk, Olga; Scheibye-Knudsen, Morten; Zhavoronkov, Alex

2018-01-11

Accurate and physiologically meaningful biomarkers for human aging are key to assessing anti-aging therapies. Given ethnic differences in health, diet, lifestyle, behaviour, environmental exposures and even average rate of biological aging, it stands to reason that aging clocks trained on datasets obtained from specific ethnic populations are more likely to account for these potential confounding factors, resulting in an enhanced capacity to predict chronological age and quantify biological age. Here we present a deep learning-based hematological aging clock modeled using the large combined dataset of Canadian, South Korean and Eastern European population blood samples that show increased predictive accuracy in individual populations compared to population-specific hematologic aging clocks. The performance of models was also evaluated on publicly-available samples of the American population from the National Health and Nutrition Examination Survey (NHANES). In addition, we explored the association between age predicted by both population-specific and combined hematological clocks and all-cause mortality. Overall, this study suggests a) the population-specificity of aging patterns and b) hematologic clocks predicts all-cause mortality. Proposed models added to the freely available Aging.AI system allowing improved ability to assess human aging. © The Author(s) 2018. Published by Oxford University Press on behalf of The Gerontological Society of America.

Genetics of the Framingham Heart Study Population

PubMed Central

Govindaraju, Diddahally R.; Cupples, L. Adrienne; Kannel, William B.; O’Donnell, Christopher J.; Atwood, Larry D.; D’Agostino, Ralph B.; Fox, Caroline S.; Larson, Marty; Levy, Daniel; Morabito, Joanne; Vasan, Ramachandran S.; Splansky, Greta Lee; Wolf, Philip A.; Benjamin, Emelia J.

2010-01-01

This article provides an introduction to the Framingham Heart Study (FHS) and the genetic research related to cardiovascular diseases conducted in this unique population1. It briefly describes the origins of the study, the risk factors that contribute to heart disease and the approaches taken to discover the genetic basis of some of these risk factors. The genetic architecture of several biological risk factors has been explained using family studies, segregation analysis, heritability, phenotypic and genetic correlations. Many quantitative trait loci underlying cardiovascular diseases have been discovered using different molecular markers. Additionally, results from genome-wide association studies using 100,000 markers, and the prospects of using 550,000 markers for association studies are presented. Finally, the use of this unique sample in genotype and environment interaction is described. PMID:19010253

Genetic Determinants of Lipid Traits in Diverse Populations from the Population Architecture using Genomics and Epidemiology (PAGE) Study

PubMed Central

Dumitrescu, Logan; Carty, Cara L.; Taylor, Kira; Schumacher, Fredrick R.; Hindorff, Lucia A.; Ambite, José L.; Anderson, Garnet; Best, Lyle G.; Brown-Gentry, Kristin; Bůžková, Petra; Carlson, Christopher S.; Cochran, Barbara; Cole, Shelley A.; Devereux, Richard B.; Duggan, Dave; Eaton, Charles B.; Fornage, Myriam; Franceschini, Nora; Haessler, Jeff; Howard, Barbara V.; Johnson, Karen C.; Laston, Sandra; Kolonel, Laurence N.; Lee, Elisa T.; MacCluer, Jean W.; Manolio, Teri A.; Pendergrass, Sarah A.; Quibrera, Miguel; Shohet, Ralph V.; Wilkens, Lynne R.; Haiman, Christopher A.; Le Marchand, Loïc; Buyske, Steven; Kooperberg, Charles; North, Kari E.; Crawford, Dana C.

2011-01-01

For the past five years, genome-wide association studies (GWAS) have identified hundreds of common variants associated with human diseases and traits, including high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) levels. Approximately 95 loci associated with lipid levels have been identified primarily among populations of European ancestry. The Population Architecture using Genomics and Epidemiology (PAGE) study was established in 2008 to characterize GWAS–identified variants in diverse population-based studies. We genotyped 49 GWAS–identified SNPs associated with one or more lipid traits in at least two PAGE studies and across six racial/ethnic groups. We performed a meta-analysis testing for SNP associations with fasting HDL-C, LDL-C, and ln(TG) levels in self-identified European American (∼20,000), African American (∼9,000), American Indian (∼6,000), Mexican American/Hispanic (∼2,500), Japanese/East Asian (∼690), and Pacific Islander/Native Hawaiian (∼175) adults, regardless of lipid-lowering medication use. We replicated 55 of 60 (92%) SNP associations tested in European Americans at p<0.05. Despite sufficient power, we were unable to replicate ABCA1 rs4149268 and rs1883025, CETP rs1864163, and TTC39B rs471364 previously associated with HDL-C and MAFB rs6102059 previously associated with LDL-C. Based on significance (p<0.05) and consistent direction of effect, a majority of replicated genotype-phentoype associations for HDL-C, LDL-C, and ln(TG) in European Americans generalized to African Americans (48%, 61%, and 57%), American Indians (45%, 64%, and 77%), and Mexican Americans/Hispanics (57%, 56%, and 86%). Overall, 16 associations generalized across all three populations. For the associations that did not generalize, differences in effect sizes, allele frequencies, and linkage disequilibrium offer clues to the next generation of association studies for these traits. PMID:21738485

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

NASA Technical Reports Server (NTRS)

Rousseaux, Cecile; Gregg, Watson

2014-01-01

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

Spatial Distribution, Structure, Biomass, and Physiology of Microbial Assemblages across the Southern Ocean Frontal Zones during the Late Austral Winter

PubMed Central

Hanson, Roger B.; Lowery, H. Kenneth

1985-01-01

We examined the spatial distributions of picoplankton, nanoplankton, and microplankton biomass and physiological state relative to the hydrography of the Southern Ocean along 90° W longitude and across the Drake Passage in the late austral winter. The eastern South Pacific Ocean showed some large-scale biogeographical differences and size class variability. Microbial ATP biomass was greatest in euphotic surface waters. The horizontal distributions of microbial biomass and physiological state (adenylate energy charge ratio) coincided with internal currents (fronts) of the Antarctic Circumpolar Current. In the Drake Passage, the biological scales in the euphotic and aphotic zones were complex, and ATP, total adenylate, and adenylate energy charge ratio isopleths were compressed due to the extension of the sea ice from Antarctica and constriction of the Circumpolar Current through the narrow passage. The physiological state of microbial assemblages and biomass were much higher in the Drake Passage than in the eastern South Pacific Ocean. The temperature of Antarctic waters, not dissolved organic carbon, was the major variable controlling picoplankton growth. Estimates of picoplankton production based on ATP increments with time suggest that production under reduced predation pressure was 1 to 10 μg of carbon per liter per day. Our results demonstrate the influence of large-scale hydrographic processes on the distribution and structure of microplankton, nanoplankton, and picoplankton across the Southern Ocean. PMID:16346777

Assimilation of Ocean-Color Plankton Functional Types to Improve Marine Ecosystem Simulations

NASA Astrophysics Data System (ADS)

Ciavatta, S.; Brewin, R. J. W.; Skákala, J.; Polimene, L.; de Mora, L.; Artioli, Y.; Allen, J. I.

2018-02-01

We assimilated phytoplankton functional types (PFTs) derived from ocean color into a marine ecosystem model, to improve the simulation of biogeochemical indicators and emerging properties in a shelf sea. Error-characterized chlorophyll concentrations of four PFTs (diatoms, dinoflagellates, nanoplankton, and picoplankton), as well as total chlorophyll for comparison, were assimilated into a physical-biogeochemical model of the North East Atlantic, applying a localized Ensemble Kalman filter. The reanalysis simulations spanned the years 1998-2003. The skill of the reference and reanalysis simulations in estimating ocean color and in situ biogeochemical data were compared by using robust statistics. The reanalysis outperformed both the reference and the assimilation of total chlorophyll in estimating the ocean-color PFTs (except nanoplankton), as well as the not-assimilated total chlorophyll, leading the model to simulate better the plankton community structure. Crucially, the reanalysis improved the estimates of not-assimilated in situ data of PFTs, as well as of phosphate and pCO2, impacting the simulation of the air-sea carbon flux. However, the reanalysis increased further the model overestimation of nitrate, in spite of increases in plankton nitrate uptake. The method proposed here is easily adaptable for use with other ecosystem models that simulate PFTs, for, e.g., reanalysis of carbon fluxes in the global ocean and for operational forecasts of biogeochemical indicators in shelf-sea ecosystems.

A method of studying wild bird populations by mist-netting and banding

USGS Publications Warehouse

Stamm, D.D.; Davis, D.E.; Robbins, C.S.

1960-01-01

1. Progress is reported toward development of a method of bird-population study based on mist-netting and banding. A definite pattern of arrangement and schedule of operation are presented. 2. Nets were operated for a total of 4200 net-hours during which 966 captures were made (23.0 birds per 100 net-hours). A total of 431 adult breeding birds were banded and 38 per cent of them were recaptured. 3. A breeding bird census was made simultaneously in the same area by the Williams spot-mapping technique. 4. Estimates of population by recapture agreed closely with the spot-mappmg census. 5. Some birds are demonstrated to have overlapping home-ranges much larger than their singing territories. 6. Recruitment and net-shyness distort recapture estimates of population .but the method allows detection and assessment of their influence in the population dealt with here. 7. The method produced integrated information on population density and dynamics, movement and behavior. 8. The procedure is especially well adapted to studies of disease agents in bird populations. 9. A simple scheme for description of the habitat in terms of relative abundance and frequency of occurrence of tree species was used.

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

Epidemiology of Benign External Hydrocephalus in Norway-A Population-Based Study.

PubMed

Wiig, Ulrikke S; Zahl, Sverre M; Egge, Arild; Helseth, Eirik; Wester, Knut

2017-08-01

Benign external hydrocephalus is defined as a rapidly increasing head circumference (occipitofrontal circumference) with characteristic radiological findings of increased subarachnoid cerebrospinal fluid spaces on neuroimaging. The incidence of benign external hydrocephalus has not been previously reported, and there is no available information on the ratio of benign external hydrocephalus in the population of hydrocephalic children. This study is retrospective and population-based study, geographically covering two health regions in the southern half of Norway with a total mean population of 3.34 million in the ten-year study period, constituting approximately 75% of the Norwegian population. Children with a head circumference crossing two percentiles, or greater than the 97.5th percentile, and with typical imaging findings of enlarged frontal subarachnoid spaces with or without enlarged ventricles were included. Children were excluded if they had a history of head trauma, intracranial hemorrhage, central nervous system infection, other known causes of hydrocephalus, or were born preterm defined as birth before 37 weeks of gestation. A total of 176 children fitting the criteria were identified, giving an incidence of 0.4 per 1000 live births. One hundred fifty-two (86.4%) of the patients were male, and mean age at referral was 7.3 months. Increasing head circumference was the main reason for referral in 158 (89.8%) patients and the only finding in 60 (34.1%) patients. Thirty-seven (21%) children had normal ventricles on imaging; the remainder had increased ventricular size. The incidence of pediatric hydrocephalus in Norway is reported to be 0.75 per 1000 live births, thus benign external hydrocephalus accounts for approximately 50% of hydrocephalic conditions in this population. The incidence of benign external hydrocephalus was found to be 0.4 per 1000 live births in this population. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights

[Design of the general population study NEMESIS-2: Netherlands Mental Health Survey and Incidence Study-2].

PubMed

de Graaf, Ron; Ten Have, Margreet; van Dorsselaer, Saskia

2012-01-01

The longitudinal epidemiological population study NEMESIS-2 (Netherlands Mental Health Survey and Incidence Study-2) replicates the first study conducted from 1996 to 1999, and expands it by adding new subjects such as impulse-control disorders. To describe the aims and design of nemesis-2, particularly of its first round of measurements, to provide up-to-date figures on prevalence, incidence, course and consequences of mental disorders and associated factors, and to study trends in the mental health of the population aged 18-64 years and the use these people make of psychiatric services. Face-to-face interviews were conducted (November 2007-July 2009) by means of the Composite International Diagnostic Interview 3.0. The response was 65.1% (n = 6646). Respondents were reasonably representative for the population, but young persons were somewhat underrepresented. Two follow-up rounds of measurements are planned with three-year intervals between the rounds. The second round of measurements began in November 2010. A qualitatively good dataset was built up. This will allow several mental health topics to be studied in the future.

Trust of Population within Social Relations System of the Population: A Case Study of Nasleg Administration in the Republic of Sakha (Yakutia)

ERIC Educational Resources Information Center

Mikhaylova, Anna; Popova, Liudmila

2016-01-01

The research consists in studying the level of population's trust in nasleg administration (in the administrative-territorial unit) of MS "Khatyryksky nasleg" of Namsky ulus using the case study. The leading research methods for the problem are empirical methods that allow revealing the level of population's trust in administration. The…

Health literacy among Saudi population: a cross-sectional study.

PubMed

Abdel-Latif, Mohamed M M; Saad, Sherif Y

2017-09-12

Health literacy is a major problem worldwide and adversely affects an individual's health. The aim of the present study was to assess health literacy level among Saudi population. A cross-sectional study was conducted among a randomly selected population (n = 500) in Saudi Arabia. The questionnaire comprised of questions pertaining to demographic characteristics, health literacy and health information. Health literacy was measured by REALM-R test. Internal reliability was determined using Cronbach's alpha coefficient. The majority of the respondents had intermediate (43.8%) and basic (34.4%) health literacy levels. A higher percentage among men had intermediate (59.8%) and basic (70.93%) health literacy levels compared with women. About 30% of respondents had difficulty in understanding health screening tests and disease treatment. More than half of participants (52.4%) had difficulty in finding health information. The REALM-R test revealed that about 42.6% of individuals with score of >6 had adequate health literacy compared with 57.4% with score of ≤6 had inadequate health literacy. The present study demonstrated that a majority of Saudi individuals had inadequate health literacy that associated with poor knowledge of health information. Our findings highlighted the importance of understanding the status of health literacy among Saudis and the need for educational programs to raise the health literacy awareness among Saudi population. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Small Crater Populations on Mars: Studies of MOC Images

NASA Technical Reports Server (NTRS)

Plaut, J. J.

2000-01-01

Populations of small martian craters can now be studied using MOC images. The smallest craters record aspects of the crater production and resurfacing history that could not be observed previously. Examples from a number of terrains are shown.

Indigenous and tribal peoples' health (The Lancet-Lowitja Institute Global Collaboration): a population study.

PubMed

Anderson, Ian; Robson, Bridget; Connolly, Michele; Al-Yaman, Fadwa; Bjertness, Espen; King, Alexandra; Tynan, Michael; Madden, Richard; Bang, Abhay; Coimbra, Carlos E A; Pesantes, Maria Amalia; Amigo, Hugo; Andronov, Sergei; Armien, Blas; Obando, Daniel Ayala; Axelsson, Per; Bhatti, Zaid Shakoor; Bhutta, Zulfiqar Ahmed; Bjerregaard, Peter; Bjertness, Marius B; Briceno-Leon, Roberto; Broderstad, Ann Ragnhild; Bustos, Patricia; Chongsuvivatwong, Virasakdi; Chu, Jiayou; Deji; Gouda, Jitendra; Harikumar, Rachakulla; Htay, Thein Thein; Htet, Aung Soe; Izugbara, Chimaraoke; Kamaka, Martina; King, Malcolm; Kodavanti, Mallikharjuna Rao; Lara, Macarena; Laxmaiah, Avula; Lema, Claudia; Taborda, Ana María León; Liabsuetrakul, Tippawan; Lobanov, Andrey; Melhus, Marita; Meshram, Indrapal; Miranda, J Jaime; Mu, Thet Thet; Nagalla, Balkrishna; Nimmathota, Arlappa; Popov, Andrey Ivanovich; Poveda, Ana María Peñuela; Ram, Faujdar; Reich, Hannah; Santos, Ricardo V; Sein, Aye Aye; Shekhar, Chander; Sherpa, Lhamo Y; Skold, Peter; Tano, Sofia; Tanywe, Asahngwa; Ugwu, Chidi; Ugwu, Fabian; Vapattanawong, Patama; Wan, Xia; Welch, James R; Yang, Gonghuan; Yang, Zhaoqing; Yap, Leslie

2016-07-09

International studies of the health of Indigenous and tribal peoples provide important public health insights. Reliable data are required for the development of policy and health services. Previous studies document poorer outcomes for Indigenous peoples compared with benchmark populations, but have been restricted in their coverage of countries or the range of health indicators. Our objective is to describe the health and social status of Indigenous and tribal peoples relative to benchmark populations from a sample of countries. Collaborators with expertise in Indigenous health data systems were identified for each country. Data were obtained for population, life expectancy at birth, infant mortality, low and high birthweight, maternal mortality, nutritional status, educational attainment, and economic status. Data sources consisted of governmental data, data from non-governmental organisations such as UNICEF, and other research. Absolute and relative differences were calculated. Our data (23 countries, 28 populations) provide evidence of poorer health and social outcomes for Indigenous peoples than for non-Indigenous populations. However, this is not uniformly the case, and the size of the rate difference varies. We document poorer outcomes for Indigenous populations for: life expectancy at birth for 16 of 18 populations with a difference greater than 1 year in 15 populations; infant mortality rate for 18 of 19 populations with a rate difference greater than one per 1000 livebirths in 16 populations; maternal mortality in ten populations; low birthweight with the rate difference greater than 2% in three populations; high birthweight with the rate difference greater than 2% in one population; child malnutrition for ten of 16 populations with a difference greater than 10% in five populations; child obesity for eight of 12 populations with a difference greater than 5% in four populations; adult obesity for seven of 13 populations with a difference greater than 10% in

Higher risk for thyroid diseases in physicians than in the general population: a Taiwan nationwide population-based secondary analysis study.

PubMed

Chen, T-Y; Hsu, C-C; Feng, I-J; Wang, J-J; Su, S-B; Guo, H-R; Huang, C-C; Lin, H-J

2017-03-01

Physicians have high work stress, responsibility for night shifts and chances of exposure to medical radiation, which may increase the risk for thyroid diseases. We conducted this study to assess the risk for thyroid diseases in physicians, which remain unclear. We used a secondary analysis of the Taiwan National Health Insurance Research Database for this study. After excluding thyroid diseases occurring before 2006 and residents, physicians and general population were identified by matching with age and sex in 2009 in a 1:2 ratio. The risk for thyroid diseases was compared between the physicians and general population and among physicians by tracing their medical histories between 2006 and 2012. In total, 28,649 physicians and 57,298 general population were identified. Physicians had a higher risk for overall thyroid diseases than the general population [odds ratio (OR): 1.27; 95% confidence interval (CI): 1.10-1.47], including individual thyroid disease: thyroid cancer (OR: 1.89; 95% CI: 1.22-2.95), hypothyroidism (OR: 1.64; 95% CI: 1.23-2.18) and thyroiditis (OR: 1.48; 95% CI: 1.00-2.19). We showed that physicians had a significantly higher risk for thyroid diseases than the general population. This reminds us to pay more attention to thyroid diseases in physicians. Further studies about the underlying mechanisms are warranted. © The Author 2016. Published by Oxford University Press on behalf of the Association of Physicians. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Nuclear DNA analyses in genetic studies of populations: practice, problems and prospects.

PubMed

Zhang, De-Xing; Hewitt, Godfrey M

2003-03-01

Population-genetic studies have been remarkably productive and successful in the last decade following the invention of PCR technology and the introduction of mitochondrial and microsatellite DNA markers. While mitochondrial DNA has proven powerful for genealogical and evolutionary studies of animal populations, and microsatellite sequences are the most revealing DNA markers available so far for inferring population structure and dynamics, they both have important and unavoidable limitations. To obtain a fuller picture of the history and evolutionary potential of populations, genealogical data from nuclear loci are essential, and the inclusion of other nuclear markers, i.e. single copy nuclear polymorphic (scnp) sequences, is clearly needed. Four major uncertainties for nuclear DNA analyses of populations have been facing us, i.e. the availability of scnp markers for carrying out such analysis, technical laboratory hurdles for resolving haplotypes, difficulty in data analysis because of recombination, low divergence levels and intraspecific multifurcation evolution, and the utility of scnp markers for addressing population-genetic questions. In this review, we discuss the availability of highly polymorphic single copy DNA in the nuclear genome, describe patterns and rate of evolution of nuclear sequences, summarize past empirical and theoretical efforts to recover and analyse data from scnp markers, and examine the difficulties, challenges and opportunities faced in such studies. We show that although challenges still exist, the above-mentioned obstacles are now being removed. Recent advances in technology and increases in statistical power provide the prospect of nuclear DNA analyses becoming routine practice, allowing allele-discriminating characterization of scnp loci and microsatellite loci. This certainly will increase our ability to address more complex questions, and thereby the sophistication of genetic analyses of populations.

Population characteristics of golden retriever lifetime study enrollees.

PubMed

Simpson, Melissa; Searfoss, Erin; Albright, Sharon; Brown, Diane E; Wolfe, Barbara; Clark, Nancy K; McCann, Susan E; Haworth, David; Guy, Mike; Page, Rod

2017-01-01

Studying cancer and other diseases poses a problem due to their protracted and multifactorial nature. Prospective studies are useful to investigate chronic disease processes since collection of lifestyle information, exposure data and co-incident health issues are collected before the condition manifests. The Golden Retriever Lifetime Study is one of the first prospective studies following privately-owned dogs throughout life to investigate the incidence and risk factors for disease outcomes, especially cancer.Owners of golden retrievers in the contiguous United States volunteered their dogs in early life. Owners and veterinarians complete online questionnaires about health status and lifestyle; dogs undergo a physical examination and collection of biological samples annually. The data presented summarize the initial study visits and the corresponding questionnaires for 3044 dogs in the cohort. The median age of dogs at enrollment was 14.0 months (interquartile range (IQR): 8-20 months). Approximately half of the population had undergone gonadectomy by their initial study visit. Medical conditions reported at enrollment consisted primarily of integumentary, gastrointestinal and urinary dysfunction. A large majority of the dogs have a record of having received preventive care (vaccines, parasiticides, flea and heartworm prevention) by the time of the initial study visit. Clinical pathology data were unremarkable. This study represents one of the first lifetime observational investigations in veterinary medicine. The population characteristics reported here indicate a healthy cohort of golden retrievers cared for by owners committed to their dogs' health. Data acquired over the study period will provide valuable information about genetic, dietary and environmental risk factors associated with disease in golden retrievers and a framework for future prospective studies in veterinary medicine.

The Relevance of HLA Sequencing in Population Genetics Studies

PubMed Central

Sanchez-Mazas, Alicia

2014-01-01

Next generation sequencing (NGS) is currently being adapted by different biotechnological platforms to the standard typing method for HLA polymorphism, the huge diversity of which makes this initiative particularly challenging. Boosting the molecular characterization of the HLA genes through efficient, rapid, and low-cost technologies is expected to amplify the success of tissue transplantation by enabling us to find donor-recipient matching for rare phenotypes. But the application of NGS technologies to the molecular mapping of the MHC region also anticipates essential changes in population genetic studies. Huge amounts of HLA sequence data will be available in the next years for different populations, with the potential to change our understanding of HLA variation in humans. In this review, we first explain how HLA sequencing allows a better assessment of the HLA diversity in human populations, taking also into account the methodological difficulties it introduces at the statistical level; secondly, we show how analyzing HLA sequence variation may improve our comprehension of population genetic relationships by facilitating the identification of demographic events that marked human evolution; finally, we discuss the interest of both HLA and genome-wide sequencing and genotyping in detecting functionally significant SNPs in the MHC region, the latter having also contributed to the makeup of the HLA molecular diversity observed today. PMID:25126587

The relevance of HLA sequencing in population genetics studies.

PubMed

Sanchez-Mazas, Alicia; Meyer, Diogo

2014-01-01

Next generation sequencing (NGS) is currently being adapted by different biotechnological platforms to the standard typing method for HLA polymorphism, the huge diversity of which makes this initiative particularly challenging. Boosting the molecular characterization of the HLA genes through efficient, rapid, and low-cost technologies is expected to amplify the success of tissue transplantation by enabling us to find donor-recipient matching for rare phenotypes. But the application of NGS technologies to the molecular mapping of the MHC region also anticipates essential changes in population genetic studies. Huge amounts of HLA sequence data will be available in the next years for different populations, with the potential to change our understanding of HLA variation in humans. In this review, we first explain how HLA sequencing allows a better assessment of the HLA diversity in human populations, taking also into account the methodological difficulties it introduces at the statistical level; secondly, we show how analyzing HLA sequence variation may improve our comprehension of population genetic relationships by facilitating the identification of demographic events that marked human evolution; finally, we discuss the interest of both HLA and genome-wide sequencing and genotyping in detecting functionally significant SNPs in the MHC region, the latter having also contributed to the makeup of the HLA molecular diversity observed today.

A study to evaluate cephalometric hard tissue profile of Tamil population for orthognathic surgery

PubMed Central

Nachiappan, S.; Tharanikumar, S.; Chandran, Ajay; Anusudha, P.; Nandini, G. D.; Balasubramaniam, Murali

2015-01-01

The primary aim of this study is to compare, the cephalometric hard tissue profile values and analysis between Tamil and Caucasian population. The study also aims to create a better understanding in the facial proportions of Tamil Nadu population and to have better diagnosis and treatment planning for orthognathic surgery for Tamil population in Tamil Nadu. PMID:26538943

A study to evaluate cephalometric hard tissue profile of Tamil population for orthognathic surgery.

PubMed

Nachiappan, S; Tharanikumar, S; Chandran, Ajay; Anusudha, P; Nandini, G D; Balasubramaniam, Murali

2015-08-01

The primary aim of this study is to compare, the cephalometric hard tissue profile values and analysis between Tamil and Caucasian population. The study also aims to create a better understanding in the facial proportions of Tamil Nadu population and to have better diagnosis and treatment planning for orthognathic surgery for Tamil population in Tamil Nadu.

Genocide Exposure and Subsequent Suicide Risk: A Population-Based Study

PubMed Central

Levine, Stephen Z.; Levav, Itzhak; Yoffe, Rinat; Becher, Yifat; Pugachova, Inna

2016-01-01

The association between periods of genocide-related exposures and suicide risk remains unknown. Our study tests that association using a national population-based study design. The source population comprised of all persons born during1922-1945 in Nazi-occupied or dominated European nations, that immigrated to Israel by 1965, were identified in the Population Register (N = 220,665), and followed up for suicide to 2014, totaling 16,953,602 person-years. The population was disaggregated to compare a trauma gradient among groups that immigrated before (indirect, n = 20,612, 9%); during (partial direct, n = 17,037, 8%); or after (full direct, n = 183,016, 83%) exposure to the Nazi era. Also, the direct exposure groups were examined regarding pre- or post-natal exposure periods. Cox regression models were used to compute Hazard Ratios (HR) of suicide risk to compare the exposure groups, adjusting for confounding by gender, residential SES and history of psychiatric hospitalization. In the total population, only the partial direct exposure subgroup was at greater risk compared to the indirect exposure group (HR = 1.73, 95% CI, 1.10, 2.73; P < .05). That effect replicated in six sensitivity analyses. In addition, sensitivity analyses showed that exposure at ages 13 plus among females, and follow-up by years since immigration were associated with a greater risk; whereas in utero exposure among persons with no psychiatric hospitalization and early postnatal exposure among males were at a reduced risk. Tentative mechanisms impute biopsychosocial vulnerability and natural selection during early critical periods among males, and feelings of guilt and entrapment or defeat among females. PMID:26901411

The Prevalence of Amblyopia and Its Determinants in a Population-based Study.

PubMed

Faghihi, Mohammad; Hashemi, Hassan; Nabovati, Payam; Saatchi, Mohammad; Yekta, Abbasali; Rafati, Shokoofeh; Ostadimoghaddam, Hadi; Khabazkhoob, Mehdi

2017-12-01

To determine the prevalence of amblyopia and its determinants in a population-based study in Mashhad County, Iran. This cross-sectional, population-based study was conducted on the population of Mashhad County aged >1 year using randomized stratified cluster sampling. Examinations were performed after selection of the participants and their free transportation to the sampling site. The examinations included the measurement of uncorrected and corrected visual acuity, cycloplegic and non-cycloplegic refraction, cover testing, slit-lamp biomicroscopy, and ophthalmoscopy. In this study, amblyopia was defined as best corrected visual acuity (BCVA) of 20/30 or less or 2-line interocular optotype acuity differences with no pathology. After considering the exclusion criteria, the data of 2739 individuals, 65.6% of whom were women, were analyzed. The mean age of the participants was 29.5±17.5 years. The prevalence of amblyopia was 4.6% (95% CI: 3.77%-5.43%) in the total population. The lowest prevalence was 2.24% in the age group 5-15 years (95% CI: 0.99%-3.48%) and the highest prevalence was 7.14% in the age group 55-65 years (95% CI: 2.64%-11.56%). Anisometropic amblyopia was observed in 45.24% of the amblyopic participants. Isometropic, mixed (strabismic/anisometropic), and strabismic amblyopia were other common causes of amblyopia, with a prevalence of 24.6%, 16.67%, and 13.49% in amblyopic patients, respectively. The odds ratio (OR) of having amblyopia for each 1-year increase in age was 1.02 (95% CI: 1.01-1.03). Amblyopia was less common in people with better socioeconomic status. This study showed the prevalence of amblyopia in all age groups in a population-based study for the first time. The findings of this study regarding the relatively high prevalence of amblyopia in the older population and its lower prevalence in young people indicate attention to amblyopia in recent years.

[Prospect and application of microsatellite population genetics in study of geoherbs].

PubMed

Zhang, Wen-Jing; Zhang, Yong-Qing; Yuan, Qing-Jun; Huang, Lu-Qi; Jiang, Dan; Jing, Li

2013-12-01

The author introduces the basic concepts of microsatellite and population genetics and its characteristics, expounds the application of these theories for population genetic structure and genetic diversity, gene flow and evolutionary significant unit ESU division research. This paper discuss its applicationin study of genetic causes, origin of cultivation, different regional origins of geoherbs, aiming at providing a new theory and method for geoherbs.

Illustrative Projections of World Populations to the 21st Century. Current Population Reports, Special Studies Series P-23, No. 79.

ERIC Educational Resources Information Center

Moore, Maurice J., Ed.; O'Connell, Martin, Ed.

The document presents high, medium, and low projections of the world's population for the year 2000. The objective of the study is to determine demands on natural resources and the environment which will be brought about by changes in the world's population. The document is presented in three major sections. Section I provides an overview of the…

[Preliminary study of HTLV-I seroprevalence in Chilean Indian populations].

PubMed

Cartier, L; Tajima, K; Araya, F; Castillo, J L; Zaninovic, V; Hayami, M; Imai, J; Born, P; Cárdenas, M; Moreno, J

1993-03-01

Aiming to seek the origin and define the prevalence of HTLV-1 infections, 464 blood samples from aboriginal populations proceeding from isolated regions of the north and south of Chile were studied. Antibodies against HTLV were measured with agglutination tests and confirmed with immuno-fluorescence and Western Blotting. Seven out of 107 (6.5%) blood samples from Atacama indians, 2 out of 202 (1%) from Mapuche indians and 3 out of 155 (1.9%) from Huilliche aborigines were positive. These results highlight an important presence of the virus in indigenous populations, specially in the extremes of the country. These findings could suggest an indigenous (mongoloid) origin of HTLV-1 in Chile, specially in Chiloe, where apparently there has been no contact with african or japanese populations, that could be the origin of the contamination.

Genome-Wide Association Study of Breast Cancer in the Japanese Population

PubMed Central

Low, Siew-Kee; Takahashi, Atsushi; Ashikawa, Kyota; Inazawa, Johji; Miki, Yoshio; Kubo, Michiaki; Nakamura, Yusuke; Katagiri, Toyomasa

2013-01-01

Breast cancer is the most common malignancy among women in worldwide including Japan. Several studies have identified common genetic variants to be associated with the risk of breast cancer. Due to the complex linkage disequilibrium structure and various environmental exposures in different populations, it is essential to identify variants associated with breast cancer in each population, which subsequently facilitate the better understanding of mammary carcinogenesis. In this study, we conducted a genome-wide association study (GWAS) as well as whole-genome imputation with 2,642 cases and 2,099 unaffected female controls. We further examined 13 suggestive loci (P<1.0×10−5) using an independent sample set of 2,885 cases and 3,395 controls and successfully validated two previously-reported loci, rs2981578 (combined P-value of 1.31×10−12, OR = 1.23; 95% CI = 1.16–.30) on chromosome 10q26 (FGFR2), rs3803662 (combined P-value of 2.79×10−11, OR = 1.21; 95% CI = 1.15–.28) and rs12922061 (combined P-value of 3.97×10−10, OR = 1.23; 95% CI = 1.15–.31) on chromosome 16q12 (TOX3-LOC643714). Weighted genetic risk score on the basis of three significantly associated variants and two previously reported breast cancer associated loci in East Asian population revealed that individuals who carry the most risk alleles in category 5 have 2.2 times higher risk of developing breast cancer in the Japanese population than those who carry the least risk alleles in reference category 1. Although we could not identify additional loci associated with breast cancer, our study utilized one of the largest sample sizes reported to date, and provided genetic status that represent the Japanese population. Further local and international collaborative study is essential to identify additional genetic variants that could lead to a better, accurate prediction for breast cancer. PMID:24143190

SHIPS: Spectral Hierarchical Clustering for the Inference of Population Structure in Genetic Studies

PubMed Central

Bouaziz, Matthieu; Paccard, Caroline; Guedj, Mickael; Ambroise, Christophe

2012-01-01

Inferring the structure of populations has many applications for genetic research. In addition to providing information for evolutionary studies, it can be used to account for the bias induced by population stratification in association studies. To this end, many algorithms have been proposed to cluster individuals into genetically homogeneous sub-populations. The parametric algorithms, such as Structure, are very popular but their underlying complexity and their high computational cost led to the development of faster parametric alternatives such as Admixture. Alternatives to these methods are the non-parametric approaches. Among this category, AWclust has proven efficient but fails to properly identify population structure for complex datasets. We present in this article a new clustering algorithm called Spectral Hierarchical clustering for the Inference of Population Structure (SHIPS), based on a divisive hierarchical clustering strategy, allowing a progressive investigation of population structure. This method takes genetic data as input to cluster individuals into homogeneous sub-populations and with the use of the gap statistic estimates the optimal number of such sub-populations. SHIPS was applied to a set of simulated discrete and admixed datasets and to real SNP datasets, that are data from the HapMap and Pan-Asian SNP consortium. The programs Structure, Admixture, AWclust and PCAclust were also investigated in a comparison study. SHIPS and the parametric approach Structure were the most accurate when applied to simulated datasets both in terms of individual assignments and estimation of the correct number of clusters. The analysis of the results on the real datasets highlighted that the clusterings of SHIPS were the more consistent with the population labels or those produced by the Admixture program. The performances of SHIPS when applied to SNP data, along with its relatively low computational cost and its ease of use make this method a promising

A Study of the Multiple Populations in M10

NASA Astrophysics Data System (ADS)

Gerber, Jeffrey M.; Friel, Eileen D.; Vesperini, Enrico

2017-06-01

We present an analysis of CN and CH band strengths which allow the identification of multiple populations in red giant stars in the globular cluster M10. Our measurements come from low-resolution spectroscopy obtained for ~140 red and asymptotic giant branch stars over two observation runs using Hydra on the WIYN 3.5m telescope. We sort the stars into nitrogen normal and enhanced populations based on the distribution of CN band strength as a function of magnitude. Once the stars are sorted into first and second generation (CN normal and enhanced, respectively), we compare this analysis to other ways of determining multiple stellar populations such as with the light elements Na and O and photometric indicators, particularly the UV photometry from the Hubble Space Telescope. C and N abundances are determined by matching observed CN and CH band measurements with those produced by synthetic spectra created with the Synthetic Spectrum Generator (SSG). The large sample size also allows us to study characteristics like radial distribution, and evolutionary effects such as the depletion of carbon (and subsequent nitrogen enrichment) as a star climbs the red giant branch. We find a rate of carbon depletion as a function of time for both populations in M10 and compare our result to M13, a cluster similar in metallicity.

On estimation of time-dependent attributable fraction from population-based case-control studies.

PubMed

Zhao, Wei; Chen, Ying Qing; Hsu, Li

2017-09-01

Population attributable fraction (PAF) is widely used to quantify the disease burden associated with a modifiable exposure in a population. It has been extended to a time-varying measure that provides additional information on when and how the exposure's impact varies over time for cohort studies. However, there is no estimation procedure for PAF using data that are collected from population-based case-control studies, which, because of time and cost efficiency, are commonly used for studying genetic and environmental risk factors of disease incidences. In this article, we show that time-varying PAF is identifiable from a case-control study and develop a novel estimator of PAF. Our estimator combines odds ratio estimates from logistic regression models and density estimates of the risk factor distribution conditional on failure times in cases from a kernel smoother. The proposed estimator is shown to be consistent and asymptotically normal with asymptotic variance that can be estimated empirically from the data. Simulation studies demonstrate that the proposed estimator performs well in finite sample sizes. Finally, the method is illustrated by a population-based case-control study of colorectal cancer. © 2017, The International Biometric Society.

Differences between blood donors and a population sample: implications for case-control studies.

PubMed

Golding, Jean; Northstone, Kate; Miller, Laura L; Davey Smith, George; Pembrey, Marcus

2013-08-01

Selecting appropriate controls for studies of genetic variation in case series is important. The two major candidates involve the use of blood donors or a random sample of the population. We compare and contrast the two different populations of controls for studies of genetic variation using data from parents enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC). In addition we compute different biases using a series of hypothetical assumptions. The study subjects who had been blood donors differed markedly from the general population in social, health-related, anthropometric, and personality-related variables. Using theoretical examples, we show that blood donors are a poor control group for non-genetic studies of diseases related to environmentally, behaviourally, or socially patterned exposures. However, we show that if blood donors are used as controls in genetic studies, these factors are unlikely to make a major difference in detecting true associations with relatively rare disorders (cumulative incidence through life of <10%). Nevertheless, for more common disorders, the reduction in accuracy resulting from the inclusion in any control population of individuals who have or will develop the disease in question can create a greater bias than can socially patterned factors. Information about the medical history of a control and the parents of the control (as a proxy for whether the control will develop the disease) is more important with regard to the choice of controls than whether the controls are a random population sample or blood donors.

Winter bird population studies and project prairie birds for surveying grassland birds

USGS Publications Warehouse

Twedt, D.J.; Hamel, P.B.; Woodrey, M.S.

2008-01-01

We compared 2 survey methods for assessing winter bird communities in temperate grasslands: Winter Bird Population Study surveys are area-searches that have long been used in a variety of habitats whereas Project Prairie Bird surveys employ active-flushing techniques on strip-transects and are intended for use in grasslands. We used both methods to survey birds on 14 herbaceous reforested sites and 9 coastal pine savannas during winter and compared resultant estimates of species richness and relative abundance. These techniques did not yield similar estimates of avian populations. We found Winter Bird Population Studies consistently produced higher estimates of species richness, whereas Project Prairie Birds produced higher estimates of avian abundance for some species. When it is important to identify all species within the winter bird community, Winter Bird Population Studies should be the survey method of choice. If estimates of the abundance of relatively secretive grassland bird species are desired, the use of Project Prairie Birds protocols is warranted. However, we suggest that both survey techniques, as currently employed, are deficient and recommend distance- based survey methods that provide species-specific estimates of detection probabilities be incorporated into these survey methods.

Studying Variance in the Galactic Ultra-compact Binary Population

NASA Astrophysics Data System (ADS)

Larson, Shane L.; Breivik, Katelyn

2017-01-01

In the years preceding LISA, Milky Way compact binary population simulations can be used to inform the science capabilities of the mission. Galactic population simulation efforts generally focus on high fidelity models that require extensive computational power to produce a single simulated population for each model. Each simulated population represents an incomplete sample of the functions governing compact binary evolution, thus introducing variance from one simulation to another. We present a rapid Monte Carlo population simulation technique that can simulate thousands of populations on week-long timescales, thus allowing a full exploration of the variance associated with a binary stellar evolution model.

Comparative study of cocoa black ants temporal population distribution utilizing geospatial analysis

NASA Astrophysics Data System (ADS)

Adnan, N. A.; Bakar, S.; Mazlan, A. H.; Yusoff, Z. Mohd; Rasam, A. R. Abdul

2018-02-01

Cocoa plantation also subjected to diseases and pests infestation. Some pests not only reduced the yield but also inhibit the growth of trees. Therefore, the Malaysia Cocoa Board (MCB) has explored Cocoa Black Ants (CBA) as one of their biological control mechanism to reduce the pest infestation of the Cocoa Pod Borer (CPB). CPB is capable to cause damage to cocoa beans, and later on will reduce the quality of dried cocoa beans. This study tries to integrate the use of geospatial analysis in understanding population distribution pattern of CBA to enhance its capability in controlling CPB infestation. Two objectives of the study are i) to generate temporal CBA distribution of cocoa plantation for two different blocks, and ii) to compare visually the CBA population distribution pattern with the aid of geospatial technique. This study managed to find the CBA population pattern which indicated spatially modest amount of low pattern distribution in February of 2007 until reaching the highest levels of ant populations in September 2007 and decreasing by the end of the year in 2009 for two different blocks (i.e 10B and 18A). Therefore, the usage of GIS is important to explain the CBA pattern population in the mature cocoa field. This finding might to be used as an indicator to examine the optimum distribution of CBA, which needed as a biological control agent against the CPB in the future.

Population-based Study of Risk Polymorphisms Associated with Vascular Disorders and Dementia

PubMed Central

Teijido, Óscar; Carril, Juan Carlos; Cacabelos, Ramón

2017-01-01

Introduction: Cardiovascular and neurodegenerative disorders are among the major causes of mortality in the developed countries. Population studies evaluate the genetic risk, i.e. the probability of an individual carrying a specific disease-associated polymorphism. Identification of risk polymorphisms is essential for an accurate diagnosis or prognosis of a number of pathologies. Aims: The aim of this study was to characterize the influence of risk polymorphisms associated with lipid metabolism, hypertension, thrombosis, and dementia, in a large population of Spanish individuals affected by a variety of brain and vascular disorders as well as metabolic syndrome. Material & Method: We performed a cross-sectional study on 4415 individuals from a widespread regional distribution in Spain (48.15% males and 51.85% females), with mental, neurodegenerative, cerebrovascular, and metabolic disorders. We evaluated polymorphisms in 20 genes involved in obesity, vascular and cardiovascular risk, and dementia in our population and compared it with representative Spanish and European populations. Risk polymorphisms in ACE, AGT(235), IL6(573), PSEN1, and APOE (specially the APOE-ε4 allele) are representative of our population as compared to the reference data of Spanish and European individuals. Conclusion: The significantly higher distribution of risk polymorphisms in PSEN1 and APOE-ε4 is characteristic of a representative number of patients with Alzheimer’s disease; whereas polymorphisms in ACE, AGT(235), and IL6(573), are most probably related with the high number of patients with metabolic syndrome or cerebrovascular damage. PMID:29081698

[Respondent-Driven Sampling: a new sampling method to study visible and hidden populations].

PubMed

Mantecón, Alejandro; Juan, Montse; Calafat, Amador; Becoña, Elisardo; Román, Encarna

2008-01-01

The paper introduces a variant of chain-referral sampling: respondent-driven sampling (RDS). This sampling method shows that methods based on network analysis can be combined with the statistical validity of standard probability sampling methods. In this sense, RDS appears to be a mathematical improvement of snowball sampling oriented to the study of hidden populations. However, we try to prove its validity with populations that are not within a sampling frame but can nonetheless be contacted without difficulty. The basics of RDS are explained through our research on young people (aged 14 to 25) who go clubbing, consume alcohol and other drugs, and have sex. Fieldwork was carried out between May and July 2007 in three Spanish regions: Baleares, Galicia and Comunidad Valenciana. The presentation of the study shows the utility of this type of sampling when the population is accessible but there is a difficulty deriving from the lack of a sampling frame. However, the sample obtained is not a random representative one in statistical terms of the target population. It must be acknowledged that the final sample is representative of a 'pseudo-population' that approximates to the target population but is not identical to it.

Population structure of two black Venezuelan populations studied through their mating structure and other related variables.

PubMed

Castro de Guerra, D; Arvelo, H; Pinto-Cisternas, J

1999-01-01

In order to obtain information about the population structure of two black Venezuelan populations with historical differences both in their origins and development, a variety of variables were utilized, especially on marital structure, including: frequency of surnames, isonymy, population genealogical consanguinity, multiple unions, and marital distances, all of which provided information and isolation, migration, endogamy, consanguinity, and patri-matrifocality. Results showed differences in the extent of isolation and endogamy, as well as differences in population structure, which can be directly related with historical conditions of each population. Results agree with those previously obtained with traditional genetic polymorphisms and with the historical information available. Thus, the usefulness of surnames for inferring about population structure is supported, as well as the usefulness of historical information for explaining genetic diversity.

Incorporating Case Studies into a World Food and Population Course

ERIC Educational Resources Information Center

Econopouly, Bethany F.; Byrne, Patrick F.; Johnson, Marc A.

2010-01-01

The use of case studies in college courses can increase student engagement with the subject matter and improve analytical, problem-solving, and communication skills. Case studies were introduced in a relatively large (54 students) undergraduate world food and population course at Colorado State University in the spring semester of 2008 and…

A systematic review of population based epidemiological studies in Myasthenia Gravis

PubMed Central

2010-01-01

Background The aim was to collate all myasthenia gravis (MG) epidemiological studies including AChR MG and MuSK MG specific studies. To synthesize data on incidence rate (IR), prevalence rate (PR) and mortality rate (MR) of the condition and investigate the influence of environmental and technical factors on any trends or variation observed. Methods Studies were identified using multiple sources and meta-analysis performed to calculate pooled estimates for IR, PR and MR. Results 55 studies performed between 1950 and 2007 were included, representing 1.7 billion population-years. For All MG estimated pooled IR (eIR): 5.3 per million person-years (C.I.:4.4, 6.1), range: 1.7 to 21.3; estimated pooled PR: 77.7 per million persons (C.I.:64.0, 94.3), range 15 to 179; MR range 0.1 to 0.9 per millions person-years. AChR MG eIR: 7.3 (C.I.:5.5, 7.8), range: 4.3 to 18.0; MuSK MG IR range: 0.1 to 0.32. However marked variation persisted between populations studied with similar methodology and in similar areas. Conclusions We report marked variation in observed frequencies of MG. We show evidence of increasing frequency of MG with year of study and improved study quality. This probably reflects improved case ascertainment. But other factors must also influence disease onset resulting in the observed variation in IR across geographically and genetically similar populations. PMID:20565885

Designing Home-Based Telemedicine Systems for the Geriatric Population: An Empirical Study.

PubMed

Narasimha, Shraddhaa; Agnisarman, Sruthy; Chalil Madathil, Kapil; Gramopadhye, Anand; McElligott, James T

2018-02-01

Background and Introduction: Telemedicine, the process of providing healthcare remotely using communication devices, has the potential to be useful for the geriatric population when specifically designed for this age group. This study explored the design of four video telemedicine systems currently available and outlined issues with these systems that impact usability among the geriatric population. Based on the results, design suggestions were developed to improve telemedicine systems for this population. Using a between-subjects experimental design, the study considered four telemedicine systems used in Medical University of South Carolina. The study was conducted at a local retirement home. The participant pool consisted of 40 adults, 60 years or older. The dependent measures used were the mean times for telemedicine session initiation and video session, mean number of errors, post-test satisfaction ratings, the NASA-Task Load Index (NASA-TLX) workload measures, and the IBM-Computer Systems Usability Questionnaire measures. Statistical significance was found among the telemedicine systems' initiation times. The analysis of the qualitative data revealed several issues, including lengthy e-mail content, icon placement, and chat box design, which affect the usability of these systems for the geriatric population. Human factor-based design modifications, including short, precise e-mail content, appropriately placed icons, and the inclusion of instructions, are recommended to address the issues found in the qualitative study.

Higher migraine risk in healthcare professionals than in general population: a nationwide population-based cohort study in Taiwan.

PubMed

Kuo, Wan-Yin; Huang, Chien-Cheng; Weng, Shih-Feng; Lin, Hung-Jung; Su, Shih-Bin; Wang, Jhi-Joung; Guo, How-Ran; Hsu, Chien-Chin

2015-01-01

High stress levels and shift work probably trigger migraine in healthcare professionals (HCPs). However, the migraine risk differences between HCPs and the general population is unknown. This nationwide population-based cohort study used Taiwan's National Health Insurance Research Database. Physicians (50,226), nurses (122,357), and other HCPs (pharmacists, technicians, dietitians, rehabilitation therapists, social workers, etc.) (45,736) were enrolled for the study cohort, and randomly selected non-HCPs (218,319) were enrolled for the comparison cohort. Conditional logistical regression analysis was used to compare the migraine risks. Comparisons between HCPs and between physician specialties were also done. Physicians, nurses, and other HCPs had higher migraine risks than did the general population (adjusted odds ratio [AOR]: 1.672; 95 % confidence interval [CI]: 1.468-1.905, AOR: 1.621; 95 % CI: 1.532-1.714, and AOR: 1.254; 95 % CI: 1.124-1.399, respectively) after stroke, hypertension, epilepsy, anxiety, depression, and insomnia had been adjusted for. Nurses and physicians had higher migraine risks than did other HCPs (AOR: 1.303; 95 % CI: 1.206-1.408, and AOR: 1.193; 95 % CI: 1.069-1.332, respectively). Obstetricians and gynecologists had a lower migraine risk than did other physician specialists (AOR: 0.550; 95 % CI: 0.323-0.937). HCPs in Taiwan had a higher migraine risk than did the general population. Heavy workloads, emotional stress, and rotating night shift sleep disturbances appear to be the most important risk factors. These findings should provide an important reference for promoting occupational health in HCPs in Taiwan.

Genetic studies among seven endogamous populations of the Koshi Zone, Bihar (India).

PubMed

Pandey, B N; Das, P K; Husain, S; Anwer, Md Rauf; Jha, A K

2003-09-01

The distribution of AB0 and Rhesus blood groups, PTC taste sensitivity and colour blindness was studied among seven endogamous populations (Tharu, Mushar, Santal, Dhobi, Julaha, Kulhaiya and Karan Kayastha) in the Koshi Zone of Bihar (India). The phenotype and allele frequencies of the four gene loci (AB0, RH, PTC and colour blindness) show considerable differences between these populations. The measurement of genetic distances revealed, that the lowest genetic distance is seen between Dhobi and Julaha, the highest between Mushar and Tharu. From the genetic distance analysis there is some evidence for a close genetic relationship among the population groups belonging to the same region, irrespective of their caste, religion, linguistic or any other affinities. It may be concluded that all these populations have arisen through a common ancestor and changed gene frequencies among them is due to evolutionary forces like mutation, selection, migration, temporal variation and genetic drift. However, these populations retain their separate entities by practising endogamy. Gene diversity analysis reveals that these populations are at an early stage of genetic differentiation.

A comparative study of the mobile population in Wuhan and other major cities.

PubMed

Zeng, Y

1997-01-01

This study examined population mobility among residents of 5 cities in China: Wuhan, Beijing, Shanghai, Guangzhou, and Shenzhen. Data were obtained from the 1995 Sample Survey of 1% of Wuhan Population and provincial Statistical Yearbooks. The total mobile population in China has increased from 20-80 million during 1982-95. Shanghai is the largest Chinese city. Beijing has a large proportion of international and internal migrants. Guangzhou is a capital city that was the first to adopt economic reforms. Migration fueled development in Shenzhen. A larger mobile population was related to larger population density. The mobile population was 20% in all cities, 30% of central city population, and 140.5% of the central city of Shenzhen. Beijing and Shanghai had the highest growth rates. Construction accounts for the largest percentage of business-related mobile population in Wuhan, Beijing, and Shanghai. Manufacturing accounts for the largest percentage in Guangzhou and Shenzhen. Most of the mobile population in capital cities such as Wuhan and Guangzhou, originates from within the provinces. The largest percentage of mobile population in Beijing and Shanghai come from adjacent provinces. Guangzhou receives many migrants from adjacent Hong Kong, Macao, and Taiwan. 47.8-78.8% of mobile population were farmers. More migrants are men. Educational levels are low. The mobile population contributes to industry and informational/cultural exchange. The migrants detract from urban areas in population pressure on housing and services, shortages of employment, illegal activities and crime, and unplanned births.

Population study of disease burden, management, and treatment of bipolar disorder in Sweden: a retrospective observational registry study.

PubMed

Carlborg, Andreas; Ferntoft, Lena; Thuresson, Marcus; Bodegard, Johan

2015-02-01

The aim of the study was to describe temporal changes in bipolar disorder during 20 years within the Swedish population and to investigate clinical and socioeconomic characteristics, drug treatment, and mortality among patients with bipolar disorder. We conducted a retrospective, nationwide registry study (the Swedish Population Register) that included all patients diagnosed with bipolar disorder (1991-2010) and linked individual data from the Swedish National Patient Register, the National Prescribed Drug Register, and the Population Register (NCT01455961). A cross-sectional cohort analysis was performed for years 2006 versus 2009. Data were analyzed using descriptive statistics. During the study period, the annual incidence of diagnosed bipolar disorder increased 3.5-fold, and patients were diagnosed at a younger age. Mortality among patients with bipolar disorder was twice that of the general population. Compared to an age-standardized population, 30% fewer patients with bipolar disorder were available for work. Among the 40% employed, 64% reported sick leave (46% >100 days/year). Despite similar education levels, disposable income was lower compared to the general population. The most commonly preceding psychiatric diagnoses were depressive or anxiety disorders. Comparing the data for 2006 and 2009 demonstrated similar somatic comorbidity burdens and socioeconomic levels. There was also a decrease in dispensed antipsychotic medications and lithium, while antiepileptic prescriptions increased slightly. Antidepressant dispenses remained virtually unchanged. In Sweden, the incidence and prevalence of diagnosed bipolar disorder have increased during the last 20 years. Compared to the general population, these patients had similar education levels, lower employment levels, less disposable income, more sick leave, and twice the mortality. A trend towards earlier diagnosis, more use of antidepressants, and less use of lithium was seen. © 2014 John Wiley & Sons A

Thyroid Dysfunction in an Adult Female Population: A population-based study of Latin American Vertebral Osteoporosis Study (LAVOS) - Puerto Rico Site Hypothyroidism in LAVOS-Puerto Rico site

PubMed Central

González-Rodríguez, Loida A.; Felici-Giovanini, Marcos E; Haddock, Lillian

2013-01-01

Objective To determine the prevalence of hypothyroidism in an adult female population in Puerto Rico and to determine the relationship between hypothyroidism, bone mineral density and vertebral and non-vertebral fractures in this population. Methods Data from the 400 subjects database of the Latin American Vertebral Osteoporosis Study (LAVOS), Puerto Rico site was reviewed. Patient’s medical history, anthropometric data, current medications, laboratories, and DXA results was extracted. Subjects with thyroid dysfunction were identified based on their previous medical history and levels of TSH. Bone Mineral Density was classified using the World Health Organization criteria. Crude prevalence of thyroid dysfunction were estimated with a confidence of 95% and weighted by the population distribution by age, according to the distribution by age group in the 2000 census. Bone mineral densities and prevalence of vertebral and non-vertebral fractures were compared among the groups. Results The weighted prevalence of hyperthyroidism in this population was 0.0043% (95% CI: −0.0021%, 0.0107%). The weighted prevalence of hypothyroidism was 24.2% (95% CI: 19.9%, 28.4%). Increased prevalence of hypothyroidism was found in participants 70 years or older. The mean BMD at spine, hip and femoral neck was similar among the groups. No difference in the proportion of participants with vertebral and non-vertebral fractures was found among the groups. Conclusion Our study found a high prevalence of hypothyroidism among adult postmenopausal females in Puerto Rico. No association between hypothyroidism and decreased bone mineral densities, vertebral or non-vertebral fractures was found in this population. PMID:23781620

[Helgoland (Germany): hemogenetic study of an island population].

PubMed

Schmidt, H D; Scheil, H G; Winkelbauer, S

2001-03-01

24 haemogenetic markers (5 erythrocyte antigenes, 6 polymorphisms of serum proteins, 12 polymorphisms of red cell enzymes) had been studied in up to 80 individuals from the island of Helgoland (Germany). The cluster analysis separates clearly the Helgoland sample from the neighbouring populations as well as from European standard data. This special position is interpreted partly by genetic peculiarities developed in the course of time, partly as a consequence of genetic drift.

Dog Ecology and Population Studies in Lagos State, Nigeria

PubMed Central

Hambolu, Sunday E.; Dzikwi, Asabe A.; Kwaga, Jacob K.P.; Kazeem, Haruna M.; Umoh, Jarlath U.; Hambolu, Dupe A.

2014-01-01

Dog population dynamics have a major impact upon the effectiveness of rabies control strategies. As such, understanding domestic dog ecology has been recognized as central to the design of effective rabies control programmes. This study was conducted to determine the dog ecology in Lagos State using compound dog count and street dog count in the three senatorial districts (Lagos West, East and Central) of Lagos State from February, 2011 to January, 2012. A total of 546 questionnaires were distributed for the compound dog count and all were completed and returned. Various aspects of dog ecology were determined, including size, sex, breed of the dog population, management of dogs and rabies awareness among the respondents. Out of the 546 compounds surveyed, 518 (94.87%) owned at least one dog. A total of 1,427 dogs were counted from the street counts while a total of 1,447 dogs (2.8 dogs/compound) were counted from the compound count. The dogs comprised of 583 males and 864 females, out of which 64.10% are confined. The dog vaccination coverage in the dog population surveyed was 64.10% and administered majorly (91.30%) by veterinarians. Security (60%) and pets (26%) were the major reasons for keeping dogs. Majority (88.80%) of the respondents were aware of rabies and its mode of transmission, but still believed in the use of concoctions (40.40%), herbs (19.90%) and consumption of the organ of the offending dog (11.50%) for the treatment of rabies. The findings of this study showed a male: female ratio of dog to be 1:1.5 and a dog: human ratio of 1:5.6. There was also a responsible dog ownership as majority of the respondents do confine, vaccinate and provide food for their dogs. Vaccination coverage of the total dog population was however below the 70-80% target recommended by the World Health Organization to achieve herd immunity. PMID:24576383

Incidence of Radiologically Isolated Syndrome: A Population-Based Study.

PubMed

Forslin, Y; Granberg, T; Jumah, A Antwan; Shams, S; Aspelin, P; Kristoffersen-Wiberg, M; Martola, J; Fredrikson, S

2016-06-01

Incidental MR imaging findings resembling MS in asymptomatic individuals, fulfilling the Okuda criteria, are termed "radiologically isolated syndrome." Those with radiologically isolated syndrome are at high risk of their condition converting to MS. The epidemiology of radiologically isolated syndrome remains largely unknown, and there are no population-based studies, to our knowledge. Our aim was to study the population-based incidence of radiologically isolated syndrome in a high-incidence region for MS and to evaluate the effect on radiologically isolated syndrome incidence when revising the original radiologically isolated syndrome criteria by using the latest radiologic classification for dissemination in space. All 2272 brain MR imaging scans in 1907 persons obtained during 2013 in the Swedish county of Västmanland, with a population of 259,000 inhabitants, were blindly evaluated by a senior radiologist and a senior neuroradiologist. The Okuda criteria for radiologically isolated syndrome were applied by using both the Barkhof and Swanton classifications for dissemination in space. Assessments of clinical data were performed by a radiology resident and a senior neurologist. The cumulative incidence of radiologically isolated syndrome was 2 patients (0.1%), equaling an incidence rate of 0.8 cases per 100,000 person-years, in a region with an incidence rate of MS of 10.2 cases per 100,000 person-years. There was no difference in the radiologically isolated syndrome incidence rate when applying a modified version of the Okuda criteria by using the newer Swanton classification for dissemination in space. Radiologically isolated syndrome is uncommon in a high-incidence region for MS. Adapting the Okuda criteria to use the dissemination in space-Swanton classification may be feasible. Future studies on radiologically isolated syndrome may benefit from a collaborative approach to ensure adequate numbers of participants. © 2016 by American Journal of Neuroradiology.

Fermi and Swift Gamma-Ray Burst Afterglow Population Studies

NASA Technical Reports Server (NTRS)

Racusin, J. L.; Oates, S. R.; Schady, P.; Burrows, D. N.; de Pasquale, M.; Donato, D.; Gehrels, N.; Koch, S.; McEnery, J.; Piran, T.;

Fermi and Swift Gamma-Ray Burst Afterglow Population Studies

NASA Technical Reports Server (NTRS)

Racusin, Judith I.

2011-01-01

The new and extreme population of GRBs detected by Fermi-LAT shows several new features in high energy gamma-rays that are providing interesting and unexpected clues into GRB prompt and afterglow emission mechanisms. Over the last 6 years, it has been Swift that has provided the robust data set of UV/optical and X-ray afterglow observations that opened many windows into components of GRB emission structure. The relationship between the LAT GRBs and the well studied, fainter, less energetic GRBs detected by Swift-BAT is only beginning to be explored by multi-wavelength studies. We explore the large sample of GRBs detected by BAT only, BAT and Fermi-GBM, and GBM and LAT, focusing on these samples separately in order to search for statistically significant differences between the populations, using only those GRBs with measured redshifts in order to physically characterize these objects. We disentangle which differences are instrumental selection effects versus intrinsic properties, in order to better understand the nature of the special characteristics of the LAT bursts.

Fermi and Swift Gamma-Ray Burst Afterglow Population Studies

NASA Technical Reports Server (NTRS)

Racusin, Judith L.; Oates, S. R.; Schady, P.; Burrows, D. N.; dePasquale, M.; Donato, D.; Gehrels, N.; Koch, S.; McEnery, J.; Piran, T.;

A comparative rugoscopic study of the dentate and edentulous individuals in the South Indian population.

PubMed

Rajguru, Jagdish Prasad; Misra, Satya Ranjan; Somayaji, Nagaveni S; Masthan, K M K; Babu, Aravindha N; Mohanty, Neeta

2014-01-01

This study analyzes the rugae pattern in dentulous and edentulous patients and also evaluates the association of rugae pattern between males and females. This study aims to investigate rugae patterns in dentulous and edentulous patients of both sexes in South Indian population and to find whether palatoscopy is a useful tool in human identification. Four hundred outpatients from Sree Balaji Dental College and Hospital, Chennai, were included in the study. The study group was equally divided between the sexes, which was further categorized into 100 dentulous and edentulous patients, respectively. The edentulous male showed the highest mean of wavy pattern and total absence of circular pattern while the edentulous female group showed the highest mean of curved pattern and total absence of nonspecific pattern, while dentate population showed similar value as that of the overall population such as straight, wavy, and curved patterns. The present study concludes that there is similar rugae pattern of distribution between male and female dentate population while there is varied pattern between the sexes of edentulous population. However, the most predominant patterns were straight, wavy, and circular patterns.

Comorbidity profile of poliomyelitis survivors in a Chinese population: a population-based study.

PubMed

Kang, Jiunn-Horng; Lin, Herng-Ching

2011-06-01

Previous reports of comorbid conditions in poliomyelitis survivors mainly focused on some disease categories, such as respiratory diseases, gastrointestinal diseases, psychiatric diseases, neurological diseases and cancer. Data regarding a wide spectrum of medical comorbidities in patients with poliomyelitis is still sparse. This study aimed to investigate and profile the wide range of comorbidities among the survivors of paralytic poliomyelitis in a Chinese population. In total, 2,032 paralytic poliomyelitis patients were selected as the study group and the comparison group consisted of 10,160 randomly selected enrollees. The comorbidities for analysis were based on a modified version of the Elixhauser Comorbidity Index. Conditional logistic regression analyses were computed to investigate the risk of comorbidities for these two groups. As compared to controls, patients with paralytic poliomyelitis had significantly higher prevalence of hypertension, ischemic heart disease, hyperlipidemia, congestive heart failure, cardiac arrhythmias, peripheral vascular disorder, stroke, paralysis, migraines, Parkinson's disease, rheumatoid arthritis, ankylosing spondylitis, pulmonary circulation disorders, chronic pulmonary disease, liver disease, peptic ulcers, hepatitis B or C, deficiency anemias, depression, and lymphoma. Most of the differences are of clinical interest, ORs often being between 2 and 3. No significant difference between poliomyelitis patients and controls was observed in the prevalence of SLE, tuberculosis, alcohol abuse and drug abuse. Our findings demonstrate that survivors of paralytic poliomyelitis in Taiwan are at higher risk of having multiple medical comorbidities although some potential confounding factors including educational level, marital status, obesity and physical activity are not available in our database. The pattern is generally consistent with previous observations from Western populations. Nevertheless, we found several novel associations

[Karyological studies of two populations of Juniperus communis L. in west Siberia].

PubMed

Mikheeva, N A; Muratova, E N

2005-01-01

Results of a karyological study of Juniperus communis L. populations under swamp and dry conditions are presented. The chromosome number of J. communis are 2n = 22. Analysis of morphological chromosome parameters showed a similarity between karyotypes of both populations. It is possible to identify one pair of asymmetric chromosomes (VIII pair); this chromosome pair is close to submetacentric type. Three pairs of chromosomes (I, VII, VIII) have secondary constrictions. Other metacentric chromosomes form groups of five long (II--VI) and three short (IX-XI) pairs. Differences between two populations in absolute chromosomal length are observed.

Study of the matrimonial structure of the population of central Sardinia (Italy).

PubMed

Vona, G; Francalacci, P; Paoli, G; Latini, V; Salis, M

1996-12-01

Temporal changes in the matrimonial structure of four Sardinian populations (Bitti, Lula, Lodè and Gavoi) have been studied. The endogamy rates and the average marriage distances indicate that the four villages experienced a long period of isolation. Only in recent decades endogamous marriages have fallen shortly. The trends of marital isonymy and inbreeding, evaluated both from isonymy and dispensation for consanguineous marriages, are similar to those of endogamy. The kinship values between pairs of populations show some preferential relationship (Bitti-Lodè, Lodè-Lula) and an evident differentiation between Gavoi and Bitti. The results also indicate that the values of kinship are not associated with the geographic distances. The possible impact of the matrimonial structure on the genetic structure and the relationships among the studied populations will be examined in further investigations, in which the genetic markers will be considered.

Prevalence of primary open-angle glaucoma in an urban south Indian population and comparison with a rural population. The Chennai Glaucoma Study.

PubMed

Vijaya, Lingam; George, Ronnie; Baskaran, M; Arvind, Hemamalini; Raju, Prema; Ramesh, S Ve; Kumaramanickavel, Govindasamy; McCarty, Catherine

2008-04-01

To estimate the prevalence and risk factors of primary open-angle glaucoma (POAG) in an urban population and compare the same with that of our published rural population data in southern India. Population-based cross-sectional study. Four thousand eight hundred subjects 40 years or older were selected using a multistage random cluster sampling procedure in Chennai city. Three thousand eight hundred fifty (80.2%) subjects underwent a complete ophthalmic examination, including applanation tonometry, gonioscopy, pachymetry, optic disc photography, and automated perimetry. Glaucoma was diagnosed using the International Society of Geographical and Epidemiological Ophthalmology Classification. The distribution of intraocular pressure (IOP) and vertical cup-to-disc ratio (VCDR) was obtained from the right eye of the 2532 subjects with normal suprathreshold visual fields. Mean IOP was 16.17+/-3.74 mmHg (97.5th and 99.5th percentiles, 24 mmHg and 30 mmHg). The mean VCDR was 0.43+/-0.17 (97.5th and 99.5th percentiles, 0.7 and 0.8). One hundred thirty-five (64 men, 71 women) subjects had POAG (3.51%; 95% confidence interval [CI], 3.04-4.0). Primary open-angle glaucoma subjects (58.4+/-11.3 years) were older (P<0.0001) than the study population (54.8+/-10.6 years). One hundred twenty-seven (94%) subjects were diagnosed to have POAG for the first time. Two subjects (1.5%) were bilaterally blind, and 3 (3.3%) were unilaterally blind due to POAG. The urban population prevalence was more than that of the rural population (1.62%; 95% CI, 1.4%-1.8%; P<0.0001). In both populations, increasing IOP (per millimeter of mercury) and older age were associated with the disease. There was no association with gender, myopia, systemic hypertension, diabetes, or central corneal thickness. The prevalence of POAG in a > or =40-year-old south Indian urban population was 3.51%, higher than that of the rural population. The prevalence increased with age, and >90% were not aware of the disease.

Wildlife disease ecology from the individual to the population: Insights from a long-term study of a naturally infected European badger population.

PubMed

McDonald, Jenni L; Robertson, Andrew; Silk, Matthew J

2018-01-01

Long-term individual-based datasets on host-pathogen systems are a rare and valuable resource for understanding the infectious disease dynamics in wildlife. A study of European badgers (Meles meles) naturally infected with bovine tuberculosis (bTB) at Woodchester Park in Gloucestershire (UK) has produced a unique dataset, facilitating investigation of a diverse range of epidemiological and ecological questions with implications for disease management. Since the 1970s, this badger population has been monitored with a systematic mark-recapture regime yielding a dataset of >15,000 captures of >3,000 individuals, providing detailed individual life-history, morphometric, genetic, reproductive and disease data. The annual prevalence of bTB in the Woodchester Park badger population exhibits no straightforward relationship with population density, and both the incidence and prevalence of Mycobacterium bovis show marked variation in space. The study has revealed phenotypic traits that are critical for understanding the social structure of badger populations along with mechanisms vital for understanding disease spread at different spatial resolutions. Woodchester-based studies have provided key insights into how host ecology can influence infection at different spatial and temporal scales. Specifically, it has revealed heterogeneity in epidemiological parameters; intrinsic and extrinsic factors affecting population dynamics; provided insights into senescence and individual life histories; and revealed consistent individual variation in foraging patterns, refuge use and social interactions. An improved understanding of ecological and epidemiological processes is imperative for effective disease management. Woodchester Park research has provided information of direct relevance to bTB management, and a better appreciation of the role of individual heterogeneity in disease transmission can contribute further in this regard. The Woodchester Park study system now offers a rare

A diffusion based study of population dynamics: Prehistoric migrations into South Asia

PubMed Central

Vahia, Mayank N.; Yadav, Nisha; Ladiwala, Uma; Mathur, Deepak

2017-01-01

A diffusion equation has been used to study migration of early humans into the South Asian subcontinent. The diffusion equation is tempered by a set of parameters that account for geographical features like proximity to water resources, altitude, and flatness of land. The ensuing diffusion of populations is followed in time-dependent computer simulations carried out over a period of 10,000 YBP. The geographical parameters are determined from readily-available satellite data. The results of our computer simulations are compared to recent genetic data so as to better correlate the migratory patterns of various populations; they suggest that the initial populations started to coalesce around 4,000 YBP before the commencement of a period of relative geographical isolation of each population group. The period during which coalescence of populations occurred appears consistent with the established timeline associated with the Harappan civilization and also, with genetic admixing that recent genetic mapping data reveal. Our results may contribute to providing a timeline for the movement of prehistoric people. Most significantly, our results appear to suggest that the Ancestral Austro-Asiatic population entered the subcontinent through an easterly direction, potentially resolving a hitherto-contentious issue. PMID:28493906

Study of fingerprints in Argentina population for application in personal identification.

PubMed

Rivaldería, Noemí; Gutiérrez-Redomero, Esperanza; Alonso-Rodríguez, Concepción; Dipierri, José E; Martín, Luis M

2017-05-01

The fingerprints of the Buenos Aires and Chubut provinces in Argentina have been studied, with the aim of knowing and quantifying the variability of these features, which are used in the identification process. The data studied for this research was obtained from 330 individuals, of both sexes, from two Argentinian population samples (170 individuals from Buenos Aires and 160 from Chubut), which amounts to a total of 3300 fingerprints. The different types of minutiae were located, identified, and visually quantified in four areas on the fingerprint. Two perpendicular axes were drawn whose intersection was located in the center of fingerprint. In addition, a circle was defined on these quadrants whose radius cut fifteen ridges. This method divides the fingerprints into four quadrants with two sectors apiece. The results obtained for both populations were compared statistically with those published previously for an Argentinian population sample, which had been collected using the same methodology. Therefore, Argentina becomes the country with the most information in this matter. For both populations, the highest frequencies were of ridge endings, followed by bifurcations and convergences. In this study of minutiae, statistically significant differences were found between the area of the fingerprint (inside and outside the circle), males and females, and types of main pattern for both samples. However, although the results show common patterns in the distribution of minutiae, there are also significant differences between populations. This reveals a significant ancestral and frequency effect of the minutiae, which would indicate that the minutiae are more genetically dependent than has been suspected so far. Furthermore, the non-equiprobability found for the frequency of the types of minutiae indicates that the weight provided by these characteristics is not the same when applied in identification processes, whether used quantitatively (numerical standard) or

Impact of different study populations on reader behavior and performance metrics: initial results

NASA Astrophysics Data System (ADS)

Gallas, Brandon D.; Pisano, Etta; Cole, Elodia; Myers, Kyle

2017-03-01

The FDA recently completed a study on design methodologies surrounding the Validation of Imaging Premarket Evaluation and Regulation called VIPER. VIPER consisted of five large reader sub-studies to compare the impact of different study populations on reader behavior as seen by sensitivity, specificity, and AUC, the area under the ROC curve (receiver operating characteristic curve). The study investigated different prevalence levels and two kinds of sampling of non-cancer patients: a screening population and a challenge population. The VIPER study compared full-field digital mammography (FFDM) to screenfilm mammography (SFM) for women with heterogeneously dense or extremely dense breasts. All cases and corresponding images were sampled from Digital Mammographic Imaging Screening Trial (DMIST) archives. There were 20 readers (American Board Certified radiologists) for each sub-study, and instead of every reader reading every case (fully-crossed study), readers and cases were split into groups to reduce reader workload and the total number of observations (split-plot study). For data collection, readers first decided whether or not they would recall a patient. Following that decision, they provided an ROC score for how close or far that patient was from the recall decision threshold. Performance results for FFDM show that as prevalence increases to 50%, there is a moderate increase in sensitivity and decrease in specificity, whereas AUC is mainly flat. Regarding precision, the statistical efficiency (ratio of variances) of sensitivity and specificity relative to AUC are 0.66 at best and decrease with prevalence. Analyses comparing modalities and the study populations (screening vs. challenge) are still ongoing.

Impact of Different Study Populations on Reader Behavior and Performance Metrics: Initial Results

PubMed Central

Gallas, Brandon D.; Pisano, Etta; Cole, Elodia; Myers, Kyle

2017-01-01

The FDA recently completed a study on design methodologies surrounding the Validation of Imaging Premarket Evaluation and Regulation called VIPER. VIPER consisted of five large reader sub-studies to compare the impact of different study populations on reader behavior as seen by sensitivity, specificity, and AUC, the area under the ROC curve (receiver operating characteristic curve). The study investigated different prevalence levels and two kinds of sampling of non-cancer patients: a screening population and a challenge population. The VIPER study compared full-field digital mammography (FFDM) to screen-film mammography (SFM) for women with heterogeneously dense or extremely dense breasts. All cases and corresponding images were sampled from Digital Mammographic Imaging Screening Trial (DMIST) archives. There were 20 readers (American Board Certified radiologists) for each sub-study, and instead of every reader reading every case (fully-crossed study), readers and cases were split into groups to reduce reader workload and the total number of observations (split-plot study). For data collection, readers first decided whether or not they would recall a patient. Following that decision, they provided an ROC score for how close or far that patient was from the recall decision threshold. Performance results for FFDM show that as prevalence increases to 50%, there is a moderate increase in sensitivity and decrease in specificity, whereas AUC is mainly flat. Regarding precision, the statistical efficiency (ratio of variances) of sensitivity and specificity relative to AUC are 0.66 at best and decrease with prevalence. Analyses comparing modalities and the study populations (screening vs. challenge) are still ongoing. PMID:28845078

Women, Co-occurring Disorders, and Violence Study: evaluation design and study population.

PubMed

McHugo, G J; Kammerer, N; Jackson, E W; Markoff, L S; Gatz, M; Larson, M J; Mazelis, R; Hennigan, K

2005-03-01

The Women, Co-occurring Disorders, and Violence Study (WCDVS) was a multi-site cooperative study to evaluate new service models for women with co-occurring mental health and substance use disorders and a history of physical and/or sexual abuse. Despite common features in the service interventions and evaluation procedures, diversity across the nine sites plus differences introduced by non-random assignment led to numerous methodological challenges. This article describes the design, measurement, and analysis decisions behind the WCDVS and lays the foundation for understanding participant-level outcomes and service costs. This article also describes the study population, as recruited and following attrition at the 6-month follow-up, in order to address the threat of selection bias to inferences drawn from this multi-site study.

The effects on the plankton community of filter-feeding Sacramento blackfish, Orthodon microlepidotus.

PubMed

Byers, Stephanie; Vinyard, Gary L

1990-06-01

A series of mesocosm experiments was performed to assess the effects on the plankton community of filter-feeding Sacramento blackfish (Cyprinidae; Orthodon microlepidotus). Phytoplankton size-frequency distribution, zooplankton abundance, primary production, potential secondary production, and nutrient concentrations were measured. Blackfish reduce numbers of both evasive and nonevasive zooplankton and large phytoplankton while enhancing nanoplankton densities. Blackfish also significantly increase primary production and potential secondary community production. Levels of dissolved inorganic phosphorus and ammonia-nitrogen also increase. The effects of blackfish are generally similar to those reported for other filter-feeding fish.

Population-based studies of antithyroid drugs and sudden cardiac death

PubMed Central

van Noord, Charlotte; Sturkenboom, Miriam C J M; Straus, Sabine M J M; Hofman, Albert; Witteman, Jacqueline C M; Stricker, Bruno H Ch

2009-01-01

AIM Thyroid free T4 is associated with QTc-interval prolongation, which is a risk factor for sudden cardiac death (SCD). Hyperthyroidism has been associated with SCD in case reports, but there are no population-based studies confirming this. The aim was to investigate whether use of antithyroid drugs (as a direct cause or as an indicator of poorly controlled hyperthyroidism) is associated with an increased risk of SCD. METHODS We studied the occurrence of SCD in a two-step procedure in two different Dutch populations. First, the prospective population-based Rotterdam Study including 7898 participants (≥55 years old). Second, we used the Integrated Primary Care Information (IPCI) database, which is a longitudinal general practice research database to see whether we could replicate results from the first study. Drug use at the index date was assessed with prescription information from automated pharmacies (Rotterdam Study) or drug prescriptions from general practices (IPCI). We used a Cox proportional hazards model in a cohort analysis, adjusted for age, gender and use of QTc prolonging drugs (Rotterdam Study) and conditional logistic regression analysis in a case–control analysis, matched for age, gender, practice and calendar time and adjusted for arrhythmia and cerebrovascular ischaemia (IPCI). RESULTS In the Rotterdam Study, 375 participants developed SCD during follow-up. Current use of antithyroid drugs was associated with SCD [adjusted hazard ratio 3.9; 95% confidence interval (CI) 1.7, 8.7]. IPCI included 1424 cases with SCD and 14 443 controls. Also in IPCI, current use of antithyroid drugs was associated with SCD (adjusted odds ratio 2.9; 95% CI 1.1, 7.4). CONCLUSIONS Use of antithyroid drugs was associated with a threefold increased risk of SCD. Although this might be directly caused by antithyroid drug use, it might be more readily explained by underlying poorly controlled hyperthyroidism, since treated patients who developed SCD still had low thyroid

Improving inferences in population studies of rare species that are detected imperfectly

USGS Publications Warehouse

MacKenzie, D.I.; Nichols, J.D.; Sutton, N.; Kawanishi, K.; Bailey, L.L.

2005-01-01

For the vast majority of cases, it is highly unlikely that all the individuals of a population will be encountered during a study. Furthermore, it is unlikely that a constant fraction of the population is encountered over times, locations, or species to be compared. Hence, simple counts usually will not be good indices of population size. We recommend that detection probabilities (the probability of including an individual in a count) be estimated and incorporated into inference procedures. However, most techniques for estimating detection probability require moderate sample sizes, which may not be achievable when studying rare species. In order to improve the reliability of inferences from studies of rare species, we suggest two general approaches that researchers may wish to consider that incorporate the concept of imperfect detectability: (1) borrowing information about detectability or the other quantities of interest from other times, places, or species; and (2) using state variables other than abundance (e.g., species richness and occupancy). We illustrate these suggestions with examples and discuss the relative benefits and drawbacks of each approach.

Strength Training and Detraining in Different Populations: Case Studies

PubMed Central

Marques, Mário C.; Zajac, Adam; Pereira, Ana; Costa, Aldo M.

2011-01-01

Many researchers have demonstrated that a specific strength training program can improve maximal strength and, the rate of force production, reduce the incidence of muscle-skeletal injury, and contribute to faster injury recovery times, thereby minimizing the number of missed practice sessions or competitions. Yet, to our best knowledge, there is no apparent consensus on the appropriate method of muscle strength and power training to enhance performance in distinct populations groups. Interruptions in training process because of illness, injury, holidays, post-season break or other factors are normal situations in any kind of sport. However, the detraining period and its consequences are not well reported in sports literature, and namely during puberty. Therefore, the aim of this paper was to discuss several case studies concerning different populations such us physical students, age-swimming competitors and elite power athletes. PMID:23487418

Hypervolemia for hypertension pathophysiology: a population-based study.

PubMed

Hür, Ender; Özişik, Melih; Ural, Cihan; Yildiz, Gürsel; Mağden, Kemal; Köse, Sennur Budak; Köktürk, Füruzan; Büyükuysal, Çağatay; Yildirim, Ibrahim; Süleymanlar, Gültekin; Ateş, Kenan; Duman, Soner

2014-01-01

Hypertension and hypervolemia relationship was proven among renal disease, although it is not known in normal population. Present study determines the fluid distribution defects in relation to blood pressure. In a population-based survey in Turkey demographics, height, weight, blood pressure, urine analysis, and serum creatinine measurements were recorded. Bioimpedance measured with the Body Composition Monitor. Total 2034 population of 71.6% male, mean age 47 ± 12.6 (18-89) years, systolic blood pressure (SBP) 134.7 ± 20, diastolic blood pressure 77.9 ± 11.6 mmHg. Body mass index (BMI) was 28.5 ± 4.5 (15.8-50.6) kg/m(2); overhydration was 0.05 ± 1.05 L. There was a correlation between extracellular water (ECW)/height and SBP (r = 0.21, P < 0.001). Receiver operating characteristic (ROC) curve with the performance of 0.60 (P < 0.001) that showed cut-off value of ECW/height was 10.06 L/m, with the 69% sensitivity and 45% specificity for SBP: 140 mmHg values. Risk factors for high SBP were increase of ECW/Height, age, BMI and presence of diabetes. ECW/height, SBP, and fat tissue index (FTI) increased in BMI categories (low, normal, and obese) and in diabetics. SBP and FTI were lower in smokers. High blood pressure may be accompanied by increased extracellular volume indices. In the future volume status assessment could be of use in evaluating the effectiveness of pharmacological intervention in the treatment of hypertension.

Fine-scale population structure of Malays in Peninsular Malaysia and Singapore and implications for association studies.

PubMed

Hoh, Boon-Peng; Deng, Lian; Julia-Ashazila, Mat Jusoh; Zuraihan, Zakaria; Nur-Hasnah, Ma'amor; Nur-Shafawati, Ab Rajab; Hatin, Wan Isa; Endom, Ismail; Zilfalil, Bin Alwi; Khalid, Yusoff; Xu, Shuhua

2015-07-22

Fine scale population structure of Malays - the major population in Malaysia, has not been well studied. This may have important implications for both evolutionary and medical studies. Here, we investigated the population sub-structure of Malay involving 431 samples collected from all states from peninsular Malaysia and Singapore. We identified two major clusters of individuals corresponding to the north and south peninsular Malaysia. On an even finer scale, the genetic coordinates of the geographical Malay populations are in correlation with the latitudes (R(2) = 0.3925; P = 0.029). This finding is further supported by the pairwise FST of Malay sub-populations, of which the north and south regions showed the highest differentiation (FST [North-south] = 0.0011). The collective findings therefore suggest that population sub-structure of Malays are more heterogenous than previously expected even within a small geographical region, possibly due to factors like different genetic origins, geographical isolation, could result in spurious association as demonstrated in our analysis. We suggest that cautions should be taken during the stage of study design or interpreting the association signals in disease mapping studies which are expected to be conducted in Malay population in the near future.

[The gene pool of Belgorod oblast population: study of biochemical gene markers in populations of Ukraine and Belarus and the position of the Belgorod population in the Eastern Slavic gene pool system].

PubMed

Lependina, I N; Churnosov, M I; Artamentova, L A; Ishchuk, M A; Tegako, O V; Balanovskaia, E V

2008-04-01

The characteristics of the gene pools of indigenous populations of Ukraine and Belarus have been studied using 28 alleles of 10 loci of biochemical gene markers (HP, GC, TF, PI, C'3, ACP1, GLO1, PGM1, ESD, and 6-PGD). The gene pools of the Russian and Ukrainian indigenous populations of Belgorod oblast (Russia) and the indigenous populations of Ukraine and Belarus have been compared. Cluster analysis, multidimensional scaling, and factor analysis of the obtained data have been used to determine the position of the Belgorod population gene pool in the Eastern Slavic gene pool system.

A Comparative Rugoscopic Study of the Dentate and Edentulous Individuals in the South Indian Population

PubMed Central

Rajguru, Jagdish Prasad; Somayaji, Nagaveni S.; Masthan, K. M. K.; Babu, Aravindha N.; Mohanty, Neeta

2014-01-01

This study analyzes the rugae pattern in dentulous and edentulous patients and also evaluates the association of rugae pattern between males and females. Aims and Objectives. This study aims to investigate rugae patterns in dentulous and edentulous patients of both sexes in South Indian population and to find whether palatoscopy is a useful tool in human identification. Materials and Methods. Four hundred outpatients from Sree Balaji Dental College and Hospital, Chennai, were included in the study. The study group was equally divided between the sexes, which was further categorized into 100 dentulous and edentulous patients, respectively. Results. The edentulous male showed the highest mean of wavy pattern and total absence of circular pattern while the edentulous female group showed the highest mean of curved pattern and total absence of nonspecific pattern, while dentate population showed similar value as that of the overall population such as straight, wavy, and curved patterns. Conclusion. The present study concludes that there is similar rugae pattern of distribution between male and female dentate population while there is varied pattern between the sexes of edentulous population. However, the most predominant patterns were straight, wavy, and circular patterns. PMID:24605051

A population study of Alzheimer's disease: findings from the Cache County Study on Memory, Health, and Aging.

PubMed

Tschanz, Joann T; Treiber, Katherine; Norton, Maria C; Welsh-Bohmer, Kathleen A; Toone, Leslie; Zandi, Peter P; Szekely, Christine A; Lyketsos, Constantine; Breitner, John C S

2005-01-01

There are several population-based studies of aging, memory, and dementia being conducted worldwide. Of these, the Cache County Study on Memory, Health and Aging is noteworthy for its large number of "oldest-old" members. This study, which has been following an initial cohort of 5,092 seniors since 1995, has reported among its major findings the role of the Apolipoprotein E gene on modifying the risk for Alzheimer's disease (AD) in males and females and identifying pharmacologic compounds that may act to reduce AD risk. This article summarizes the major findings of the Cache County study to date, describes ongoing investigations, and reports preliminary analyses on the outcome of the oldest-old in this population, the subgroup of participants who were over age 84 at the study's inception.

COMPARISON OF SAMPLING TECHNIQUES USED IN STUDYING LEPIDOPTERA POPULATION DYNAMICS

EPA Science Inventory

Four methods (light traps, foliage samples, canvas bands, and gypsy moth egg mass surveys) that are used to study the population dynamics of foliage-feeding Lepidoptera were compared for 10 species, including gypsy moth, Lymantria dispar L. Samples were collected weekly at 12 sit...

The Role of Local Ancestry Adjustment in Association Studies Using Admixed Populations

PubMed Central

Zhang, Jianqi; Stram, Daniel O.

2016-01-01

Association analysis using admixed populations imposes challenges and opportunities for disease mapping. By developing some explicit results for the variance of an allele of interest conditional on either local or global ancestry and by simulation of recently admixed genomes we evaluate power and false-positive rates under a variety of scenarios concerning linkage disequilibrium (LD) and the presence of unmeasured variants. Pairwise LD patterns were compared between admixed and nonadmixed populations using the HapMap phase 3 data. Based on the above, we showed that as follows: For causal variants with similar effect size in all populations, power is generally higher in a study using admixed population than using nonadmixed population, especially for highly differentiated SNPs. This gain of power is achieved with adjustment of global ancestry, which completely removes any cross-chromosome inflation of type I error rates, and addresses much of the intrachromosome inflation.If reliably estimated, adjusting for local ancestry precisely recovers the localization that could have been achieved in a stratified analysis of source populations. Improved localization is most evident for highly differentiated SNPs; however, the advantage of higher power is lost on exactly the same differentiated SNPs.In the real admixed populations such as African Americans and Latinos, the expansion of LD is not as dramatic as in our simulation.While adjustment for global ancestry is required prior to announcing a novel association seen in an admixed population, local ancestry adjustment may best be regarded as a localization tool not strictly required for discovery purposes. PMID:25043967

Population pharmacogenetics of Ibero-Latinoamerican populations (MESTIFAR 2014).

PubMed

Sosa-Macias, Martha; Moya, Graciela E; LLerena, Adrián; Ramírez, Ronald; Terán, Enrique; Peñas-LLedó, Eva M; Tarazona-Santos, Eduardo; Galaviz-Hernández, Carlos; Céspedes-Garro, Carolina; Acosta, Hildaura

2015-01-01

MESTIFAR 2014 28-30 November 2014, Panama City, Panama The CEIBA consortium was created within the Ibero-American network of Pharmacogenetics (RIBEF) to study population pharmacogenetics. The current status of these initiatives and results of the MESTIFAR project were analyzed in Panama, 28-30 November 2014. The MESTIFAR project focused on studying CYPs genetic polymorphisms in populations of different ethnic origin. So far, more than 6000 healthy volunteers have been evaluated, making this one of the largest population pharmacogenomic studies worldwide. Three symposia were organized, 'Pharmacogenetics of indigenous and mestizos populations and its clinical implications', 'Methodological innovation in pharmacogenetics and its application in health', and 'General discussion and concluding remarks', about mechanisms and proposals for training, diffusion of pharmacogenetics for Spanish- and Portuguese-speaking health professionals, and 'bench to bedside' pilot projects.

A Population-based study of dementia in the oldest old: the Monzino 80-plus Study

PubMed Central

2011-01-01

Background Despite being the fastest growing and the most cognitively impaired age group, the oldest olds are under-represented in clinical research. The purpose of this study was to describe the design, methods, and baseline characteristics of the survey population and investigate possible differences in demographic, cognitive, functional, and behavioral characteristics between oldest old with and without any performance on cognitive tests and between oldest old alive and those deceased prior to the interview. Methods The Monzino 80-plus Study is a prospective door-to-door population-based survey among 80 years or older residents in the municipalities in the province of Varese, Italy. Dementia cases were identified with a one-phase design. Trained psychologists interviewed both the subject and a proxy informant. The interview included a comprehensive standardized questionnaire together with an array of rating scales and a multidomain cognitive battery to assess cognitive and functional ability, behavioral disturbances and mood. Results Information was available for 2,139 of the 2,428 registered individuals aged 80 years or older. Main baseline characteristics of the population are reported and discussed. In comparison with those living, elderly persons who had died before the first visit were older, had twice the rate of institutionalization, poorer cognitive performance and competence, and significantly greater instrumental and basic functional disability. The percentage of elderly persons, alive at baseline, without Mini-Mental State Examination rose rather evenly with age. Moreover, they had significantly worse cognitive competence and functional ability, and reported higher prevalences of depressive symptoms and problem behaviors than those with Mini-Mental State Examination. Conclusions Prospective investigation of a large population of oldest old can contribute significantly to understanding the relations between age, cognitive decline, and dementia

Genetic studies of stuttering in a founder population.

PubMed

Wittke-Thompson, Jacqueline K; Ambrose, Nicoline; Yairi, Ehud; Roe, Cheryl; Cook, Edwin H; Ober, Carole; Cox, Nancy J

2007-01-01

Genome-wide linkage and association analyses were conducted to identify genetic determinants of stuttering in a founder population in which 48 individuals affected with stuttering are connected in a single 232-person genealogy. A novel approach was devised to account for all necessary relationships to enable multipoint linkage analysis. Regions with nominal evidence for linkage were found on chromosomes 3 (P=0.013, 208.8 centiMorgans (cM)), 13 (P=0.012, 52.6 cM), and 15 (P=0.02, 100 cM). Regions with nominal evidence for association with stuttering that overlapped with a linkage signal are located on chromosomes 3 (P=0.0047, 195 cM), 9 (P=0.0067, 46.5 cM), and 13 (P=0.0055, 52.6 cM). We also conducted the first meta-analysis for stuttering using results from linkage studies in the Hutterites and The Illinois International Genetics of Stuttering Project and identified regions with nominal evidence for linkage on chromosomes 2 (P=0.013, 180-195 cM) and 5 (P=0.0051, 105-120 cM; P=0.015, 120-135 cM). None of the linkage signals detected in the Hutterite sample alone, or in the meta-analysis, meet genome-wide criteria for significance, although some of the stronger signals overlap linkage mapping signals previously reported for other speech and language disorders. After reading this article, the reader will be able to: (1) summarize information about the background of common disorders and methodology of genetic studies; (2) evaluate the role of genetics in stuttering; (3) discuss the value of using founder populations in genetic studies; (4) articulate the importance of combining several studies in a meta-analysis; (5) discuss the overlap of genetic signals identified in stuttering with other speech and language disorders.

Population inertia and its sensitivity to changes in vital rates and population structure

USGS Publications Warehouse

Koons, David N.; Holmes, Randall R.; Grand, James B.

2007-01-01

Because the (st)age structure of a population may rarely be stable, studies of transient population dynamics and population momentum are becoming ever more popular. Yet, studies of "population momentum" are restricted in the sense that they describe the inertia of population size resulting from a demographic transition to the stationary population growth rate. Although rarely mentioned, inertia in population size is a general phenomenon and can be produced by any demographic transition or perturbation. Because population size is of central importance in demography, conservation, and management, formulas relating the sensitivity of population inertia to changes in underlying vital rates and population structure could provide much-needed insight into the dynamics of populations with unstable (st)age structure. Here, we derive such formulas, which are readily computable, and provide examples of their potential use in studies of life history and applied arenas of population study. ?? 2007 by the Ecological Society of America.

How have researchers studied multiracial populations? A content and methodological review of 20 years of research.

PubMed

Charmaraman, Linda; Woo, Meghan; Quach, Ashley; Erkut, Sumru

2014-07-01

The U.S. Census shows that the racial-ethnic makeup of over 9 million people (2.9% of the total population) who self-identified as multiracial is extremely diverse. Each multiracial subgroup has unique social and political histories that may lead to distinct societal perceptions, economic situations, and health outcomes. Despite the increasing academic and media interest in multiracial individuals, there are methodological and definitional challenges in studying the population, resulting in conflicting representations in the literature. This content and methods review of articles on multiracial populations provides a comprehensive understanding of which multiracial populations have been included in research and how they have been studied, both to recognize emerging research and to identify gaps for guiding future research on this complex but increasingly visible population. We examine 125 U.S.-based peer-reviewed journal articles published over the past 20 years (1990 to 2009) containing 133 separate studies focused on multiracial individuals, primarily from the fields of psychology, sociology, social work, education, and public health. Findings include (a) descriptive data regarding the sampling strategies, methodologies, and demographic characteristics of studies, including which multiracial subgroups are most studied, gender, age range, region of country, and socioeconomic status; (b) major thematic trends in research topics concerning multiracial populations; and (c) implications and recommendations for future studies.

Genetic variations in the Dravidian population of South West coast of India: Implications in designing case-control studies.

PubMed

D'Cunha, Anitha; Pandit, Lekha; Malli, Chaithra

2017-06-01

Indian data have been largely missing from genome-wide databases that provide information on genetic variations in different populations. This hinders association studies for complex disorders in India. This study was aimed to determine whether the complex genetic structure and endogamy among Indians could potentially influence the design of case-control studies for autoimmune disorders in the south Indian population. A total of 12 single nucleotide variations (SNVs) related to genes associated with autoimmune disorders were genotyped in 370 healthy individuals belonging to six different caste groups in southern India. Allele frequencies were estimated; genetic divergence and phylogenetic relationship within the various caste groups and other HapMap populations were ascertained. Allele frequencies for all genotyped SNVs did not vary significantly among the different groups studied. Wright's FSTwas 0.001 per cent among study population and 0.38 per cent when compared with Gujarati in Houston (GIH) population on HapMap data. The analysis of molecular variance results showed a 97 per cent variation attributable to differences within the study population and <1 per cent variation due to differences between castes. Phylogenetic analysis showed a separation of Dravidian population from other HapMap populations and particularly from GIH population. Despite the complex genetic origins of the Indian population, our study indicated a low level of genetic differentiation among Dravidian language-speaking people of south India. Case-control studies of association among Dravidians of south India may not require stratification based on language and caste.

Morphometric Study of Clavicular Facet of Coracoclavicular Joint in Adult Indian Population

PubMed Central

Mahajan, Anita; Vasudeva, Neelam

2016-01-01

Introduction Anthropologists have used Coracoclavicular Joint (CCJ), a non-metric anatomical variant in population, as a marker for population migration from prehistoric times to present. Aim The aim of this osteological study was to determine the incidence and morphometry of articular facet of CCJ on conoid tubercle of clavicle in Indian population, as Indian studies are scanty and incomplete. Materials and Methods The study was done on 144 adult human clavicles (76 right and 68 left; 93 males and 51 females) collected from osteology museum in Department of Anatomy, Maulana Azad Medical College, New Delhi, India. The presence of articular facet on the conoid tubercle was determined and Maximum Antero-Posterior (MAPD) and maximum transverse diameter (MTD) was measured by digital vernier calliper. The incidence was compared on the basis of sex, side and with other osteological studies in the world. Statistical analysis was done using the Chi-Square test for nominal categorical data and student’s t-test for normally distributed continuous variables in Microsoft Excel 2007 to assess the relationship between the examined variables. Results Articular facet on conoid tubercle was found in 8 cases (5.6%). Seven (9.2%) were present on the right side and one (1.5%) on the left side. Seven cases (7.5%) were present in males and one case (2%) was found in females. The facets were generally oval, with MAPD and MTD of 12.28 and 17.17 mm respectively. A significant side variation was present with right sided facet being more common. The left sided facet was more transversely elongated than right. In males, the facets were more elongated antero-posteriorly than in females. Conclusion The Indian population showed an incidence of 5.6%, which was comparable to other ethnic groups in world population. The morphometric and side differences could be attributed to the occupational factors and range of movements associated with the CCJ. The CCJ should be borne in mind as a differential

Epidemiology of amyotrophic lateral sclerosis in Minnesota: a year-long population based study.

PubMed

Harper, Caitlin J; Sorenson, Eric J; Mandrekar, Jay

2015-01-01

This is the largest population based study of ALS in the U.S., encompassing the population of Minnesota (> 5.4 million people) from July 2013 to July 2014. Data on gender, age at diagnosis, and residential county were collected for all Minnesota residents who registered with the Minnesota/North Dakota/South Dakota chapter of the ALS Association from July 2013 to July 2014. Incidence rates were calculated as the number of new cases of ALS per 100,000 people per year. The standardized incidence rates for the 2013 U.S. population and the 2013 European standard population were also reported. Results showed that the crude incidence rate of ALS was 2.2 cases per 100,000 person-years. Incidence increased with age, peaking at 70-79 years (8.3 per 100,000) with mean age at diagnosis 64 years, and was greater in males (2.4 per 100,000) than in females (1.5 per 100,000). Standardized incidence rates for the 2013 U.S. and European standard population were 2.2 and 2.39 cases per 100,000 person-years, respectively. In conclusion, the overall incidence and age and gender patterns of ALS in Minnesota are comparable to those reported by European studies ( 1-5 ).

Increasing incidence of pyogenic spondylodiscitis: a 14-year population-based study.

PubMed

Kehrer, Michala; Pedersen, Court; Jensen, Thøger G; Lassen, Annmarie T

2014-04-01

Smaller studies indicate that the incidence of pyogenic spondylodiscitis is increasing, possible related to a growing elderly population. Data supporting this is sparse, and we therefore studied patient characteristics and changes in spondylodiscitis incidence 1995-2008. In a population-based study we identified all patients aged ≥18 years treated for pyogenic spondylodiscitis in Funen County, Denmark (population 483 123). Annual incidences were determined. Demographics, symptoms and diagnostic methods were recorded. We found 192 cases: median age 66.6 years; 57.3% men; 76.6% culture positive cases. Staphylococcus aureus was the most common pathogen (55.1%). During 1995-2008 the overall incidence, incidence of culture negative cases, and incidence of cases due to S. aureus increased 2.2-5.8, 0.3-1.8, and 1.6-2.5 cases per 100 000 person years, respectively. The elderly had the highest incidence compared to those aged ≤70 years (rate ratio for men 5.9 (95% CI: 4.2-8.5) and for women 3.5 (95% CI: 2.3-5.3)). During 1995-2008 the overall incidence of S. aureus and culture negative cases of spondylodiscitis increased and remained highest among the elderly. Whether the increase is real or is a result of improved diagnostic methods and workup remains unknown. Copyright © 2013 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Epidemiology of Amyotrophic Lateral Sclerosis: A Population-Based Study in Israel.

PubMed

Weil, Clara; Zach, Neta; Rishoni, Shay; Shalev, Varda; Chodick, Gabriel

2016-01-01

Globally, the annual incidence and prevalence of amyotrophic lateral sclerosis (ALS) are estimated at 1.9 and 4.5 per 100,000 population, respectively. This study is aimed at describing the epidemiology of ALS in Israel in a real-world setting. A retrospective study was performed using the databases of Maccabi Healthcare Services (MHS), a 2-million-member health maintenance organization in Israel. The study included all MHS adults diagnosed with ALS between 1997 and 2013. In 2013, characteristics of ALS patients were compared to those of age-sex-matched patients without ALS. Survival after ALS diagnosis was assessed until death and until tracheostomy or death (follow-up through 2014). In 2013 (n = 158), the prevalence of ALS was 8.1 per 100,000 population in MHS. In 1997-2013, a total of 375 ALS patients were diagnosed, corresponding to an average annual incidence of 1.8 per 100,000 population in MHS. The median survival from diagnosis to death was 3.5 years (95% CI 2.9-4.1), with approximately 28% surviving at least 10 years. Median tracheostomy-free survival was 2.5 years (95% CI 2.1-2.9). Results suggest that there is a relatively high prevalence of ALS in Israel. Further research is needed to investigate factors that may contribute to the survival of patients with ALS in Israel. © 2016 S. Karger AG, Basel.

Surnames in Honduras: A study of the population of Honduras through isonymy.

PubMed

Herrera Paz, Edwin Francisco; Scapoli, Chiara; Mamolini, Elisabetta; Sandri, Massimo; Carrieri, Alberto; Rodriguez-Larralde, Alvaro; Barrai, Italo

2014-05-01

In this work, we investigated surname distribution in 4,348,021 Honduran electors with the aim of detecting population structure through the study of isonymy in three administrative levels: the whole nation, the 18 departments, and the 298 municipalities. For each administrative level, we studied the surname effective number, α, the total inbreeding, FIT , the random inbreeding, FST , and the local inbreeding, FIS . Principal components analysis, multidimensional scaling, and cluster analysis were performed on Lasker's distance matrix to detect the direction of surname diffusion and for a graphic representation of the surname relationship between different locations. The values of FIT , FST , and FIS display a variation of random inbreeding between the administrative levels in the Honduras population, which is attributed to the "Prefecture effect." Multivariate analyses of department data identified two main clusters, one south-western and the second north-eastern, with the Bay Islands and the eastern Gracias a Dios out of the main clusters. The results suggest that currently the population structure of this country is the result of the joint action of short-range directional migration and drift, with drift dominating over migration, and that population diffusion may have taken place mainly in the NW-SE direction. © 2014 John Wiley & Sons Ltd/University College London.

Accounting for Population Structure in Gene-by-Environment Interactions in Genome-Wide Association Studies Using Mixed Models.

PubMed

Sul, Jae Hoon; Bilow, Michael; Yang, Wen-Yun; Kostem, Emrah; Furlotte, Nick; He, Dan; Eskin, Eleazar

2016-03-01

Although genome-wide association studies (GWASs) have discovered numerous novel genetic variants associated with many complex traits and diseases, those genetic variants typically explain only a small fraction of phenotypic variance. Factors that account for phenotypic variance include environmental factors and gene-by-environment interactions (GEIs). Recently, several studies have conducted genome-wide gene-by-environment association analyses and demonstrated important roles of GEIs in complex traits. One of the main challenges in these association studies is to control effects of population structure that may cause spurious associations. Many studies have analyzed how population structure influences statistics of genetic variants and developed several statistical approaches to correct for population structure. However, the impact of population structure on GEI statistics in GWASs has not been extensively studied and nor have there been methods designed to correct for population structure on GEI statistics. In this paper, we show both analytically and empirically that population structure may cause spurious GEIs and use both simulation and two GWAS datasets to support our finding. We propose a statistical approach based on mixed models to account for population structure on GEI statistics. We find that our approach effectively controls population structure on statistics for GEIs as well as for genetic variants.

Study design and implementation for population pharmacokinetics of Chinese medicine: An expert consensus.

PubMed

Jiang, Jun-jie; Zhang, Wen; Xie, Yan-ming; Wang, Jian-nong; He, Fu-yuan; Xiong, Xin

2016-02-01

Although many population pharmacokinetics (PPK) researches have been conducted on chemical drugs, few have been in the field of Chinese medicine (CM). Each ingredient in CMs possesses different pharmacokinetic characteristics, therefore, it is important to develop methods of PPK studies on them to identify the differences in CM drug safety and efficacy among the population subgroups and to conduct quantitative studies on the determinants of CM drug concentrations. To develop an expert consensus on study design and implementation for PPK of CM, in August 2013, 6 experts in the field of PPK, CMs pharmacology, and statistics discussed problems on the PPK research protocol of CMs, and a consensus was reached. The medicines with toxicity and narrow therapeutic windows and with wide range of target population or with frequent adverse reactions were selected. The compositions with definite therapeutic effects were selected as indices, and specific time points and sample sizes were designed according to standard PPK design methods. Target components were tested through various chromatography methods. Total quantity statistical moment analysis was used to estimate PPK parameters of each component and PPK models reflecting the trend of CMs (which assists in reasonable adjustments on clinical dosage). This consensus specifies the study design and implementation process of PPK. It provides guidance for the following: post-marketing clinical studies, in vivo investigations related to the metabolism in different populations, and development and clinical adjustment of dosages of CMs.

Diversity of human lip prints: a collaborative study of ethnically distinct world populations.

PubMed

Sharma, Namita Alok; Eldomiaty, Magda Ahmed; Gutiérrez-Redomero, Esperanza; George, Adekunle Olufemi; Garud, Rajendra Somnath; Sánchez-Andrés, Angeles; Almasry, Shaima Mohamed; Rivaldería, Noemí; Al-Gaidi, Sami Awda; Ilesanmi, Toyosi

2014-01-01

Cheiloscopy is a comparatively recent counterpart to the long established dactyloscopic studies. Ethnic variability of these lip groove patterns has not yet been explored. This study was a collaborative effort aimed at establishing cheiloscopic variations amongst modern human populations from four geographically and culturally far removed nations: India, Saudi Arabia, Spain and Nigeria. Lip prints from a total of 754 subjects were collected and each was divided into four equal quadrants. The patterns were classified into six regular types (A-F), while some patterns which could not be fitted into the regular ones were segregated into G groups (G-0, G-1, G-2). Furthermore, co-dominance of more than one pattern type in a single quadrant forced us to identify the combination (COM, G-COM) patterns. The remarkable feature noted after compilation of the data included pattern C (a bifurcate/branched prototype extending the entire height of the lip) being a frequent feature of the lips of all the populations studied, save for the Nigerian population in which it was completely absent and which showed a tendency for pattern A (a vertical linear groove) and a significantly higher susceptibility for combination (COM) patterns. Chi-square test and correspondence analysis applied to the frequency of patterns appearing in the defined topographical areas indicated a significant variation for the populations studied.

Drug-induced QT interval prolongation: does ethnicity of the thorough QT study population matter?

PubMed Central

Shah, Rashmi R

2013-01-01

Inter-ethnic differences in drug responses have been well documented. Drug-induced QT interval prolongation is a major safety concern and therefore, regulatory authorities recommend a clinical thorough QT study (TQT) to investigate new drugs for their QT-prolonging potential. A positive study, determined by breach of a preset regulatory threshold, significantly influences late phase clinical trials by requiring intense ECG monitoring. A few studies that are currently available, although not statistically conclusive at present, question the assumption that ethnicity of the study population may not influence the outcome of a TQT study. Collective consideration of available pharmacogenetic and clinical information suggests that there may be inter-ethnic differences in QT-prolonging effects of drugs and that Caucasians may be more sensitive than other populations. The information also suggest s that (a) these differences may depend on the QT-prolonging potency of the drug and (b) exposure–response (E–R) analysis may be more sensitive than simple changes in QTc interval in unmasking this difference. If the QT response in Caucasians is generally found to be more intense than in non-Caucasians, there may be significant regulatory implications for domestic acceptance of data from a TQT study conducted in foreign populations. However, each drug will warrant an individual consideration when extrapolating the results of a TQT studyfrom one ethnic population to another and the ultimate clinical relevance of any difference. Further adequately designed and powered studies, investigating the pharmacologic properties and E–R relationships of additional drugs with different potencies, are needed in Caucasians, Oriental/Asian and African populations before firm conclusions can be drawn. PMID:22882246

The TSH levels and risk of hypothyroidism: Results from a population based prospective cohort study in an Iranian adult's population.

PubMed

Aminorroaya, Ashraf; Meamar, Rokhsareh; Amini, Massoud; Feizi, Awat; Nasri, Maryam; Tabatabaei, Azamosadat; Faghihimani, Elham

2017-06-01

The aim of current study was to assess the relationship between serum TSH levels and hypothyroidism risk in the euthyroid population. In a population-based cohort study, a total of 615 individuals with a normal baseline TSH, from of total population (n=2254) in 2006, were followed up for 6years. TSH, total T4, thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TgAb) were measured. The relative risk (RR) and 95% confidence interval (95%CI) were calculated based on logistic regression. The Receiver Operating Characteristic (ROC) analysis along with area under the curve (AUC) was used to prediction of future hypothyroidism. TSH level in 2006 was a significant predictor for overt hypothyroidism, in the total population (RR=3.5) and female (RR=1.37) (all, P value<0.05). A cutoff value of TSH at 2.05mIU/L [AUC: (CI95 %), 0.68 (0.44-0.92; P=0.05)] was obtained for differentiating the patients with overt hypothyroidism from euthyroid. However, this cut off was not observed when we included only negative TPO and TgAbs people in 2006. The RR of hypothyroidism increased gradually when TSH level increased from 2.06-3.6mIU/L to >3.6mIU/L in the total population and both sexes. In women, the risk of overt hypothyroidism was significantly higher in subjects with TSH above 3.6 than those subject with THS levels≤2.05 [RR: (CI95 %), 20.57(2.-207.04), P value<0.05]. A cutoff value of TSH at 2.05mIU/L could predict the development of overt hypothyroidism in future. However, it was not applicable for people with negative TPOAb and negative TgAb. Copyright © 2016 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

Persistent opioid use and socio-economic factors: a population-based study in Norway.

PubMed

Svendsen, Kristian; Fredheim, Olav M; Romundstad, Pål; Borchgrevink, Petter C; Skurtveit, Svetlana

2014-04-01

A growing proportion of the population is using opioids for longer time periods, but little is known about the characteristics of patients who are persistent opioid users. We therefore studied the association between socio-economic factors and persistent vs. short-term opioid use 4 years later. The background population is the complete Norwegian population in 2001. The study population is derived from two groups aged 35 years or older in 2001 who met one of the following criteria in 2005: (1) persistent opioid users (n = 15,113) or (2) short-term opioid users (n = 214,061). The applied definition of persistent opioid use corresponds to an average daily dose indicating likely daily use of opioids during 365 consecutive days. The socio-economic factors work status, income, marital status, immigrant status and education were obtained from the Population and Housing Census of 2001, and data on opioid use in 2005 were obtained from the complete national Norwegian Prescription Database. For logistic regression analyses, the study population was stratified by gender and by age over/under 67 years. In the 35- to 67-year-old age group, receiving a disability pension was more common in persistent opioid users compared with short-term opioid users (48% vs. 16% for women, 36% vs. 9% for men). Adjusted odds ratios for receiving a disability pension were 6.51 and 5.77 for women and men, respectively. Being divorced/separated was associated with being a persistent opioid user (odds ratio of 1.4 for both genders). There were also negative associations between persistent opioid use and attained education level, an unemployed working status and income status. Disability pension, not working, divorce, low income and low education in 2001 were associated with persistent opioid use in 2005. © 2014 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

A study of the periodontal state of a late Medieval United Kingdom population.

PubMed

Gonçalves, Pedro César Gaspar; Griffiths, Gareth; Rawlinson, Andrew

2015-12-01

To study the severity of bone loss in a Medieval UK population, and compare this with other ancient UK populations from different time periods. Skulls from a burial site in York (XI-XV century) were investigated. Skulls with a minimum of 17 teeth were included and were divided from childhood into five age groups. Direct measurements from the cement enamel junction (CEJ) to the alveolar crest (AC) were undertaken at six points around each tooth with a UNC 15 probe. The mean bone loss was calculated for each tooth type. Seventy five skulls were included in the study (12-60 years of age). Bone loss was found to increase with age, but stabilized in older individuals (>45 years). The mean CEJ-AC distance varied from 2.1mm in the youngest group to a maximum of 4.1mm in 36-45 year olds. Results were compared with a Roman-British population (Whittaker et al., 1982) where comparable values for mean bone loss were 2.2mm and 5.4mm respectively, and a population of XVIII century Londoners (Whittaker et al., 1998) where bone loss of 1.1mm and 4.0mm was reported for the youngest and oldest age groups respectively. Measuring the CEJ-AC distance in dried skulls from ancient populations may be used as a proxy for the levels of periodontal disease irrespective of tooth wear. The findings from the current study suggest that the severity of periodontitis as determined by measurements of alveolar bone loss on dried skulls from this ancient population, seems to have declined in the United Kingdom from the III-V century to XVIII century. This may be due to changes in environmental factors including living conditions and diet, together with individual characteristics including systemic illness and genetic make up. Copyright © 2015. Published by Elsevier Ltd.

Morphometric study of the lumbar spinal canal in the Korean population.

PubMed

Lee, H M; Kim, N H; Kim, H J; Chung, I H

1995-08-01

The anatomic dimensions of the vertebral body and spinal canal of the lumbar spine were analyzed in Koreans. To determine the normal dimension of the lumbar spinal canal in Koreans, to determine whether there are any racial differences in the morphometry of the lumbar spinal canal, and to provide criteria for diagnosing spinal stenosis in the Far Eastern Asian. Some radiologic and anatomic studies have been conducted regarding the size of the lumbar spinal canal of whites and blacks in western and African countries. One-thousand-eight-hundred measurements were performed on the transverse and sagittal diameters of vertebral bodies and spinal canals using complete sets of 90 lumbar vertebrae. The mean mid-sagittal diameter of the lumbar spinal canal in the Korean population was less than that measured in white and African populations, but there was no significant differences between the Korean, white, and African populations regarding the transverse diameter of the lumbar spinal canal. The mid-sagittal diameter of the lumbar spinal canal is narrowest in the Far Eastern Asian population; the radiologic criteria of spinal stenosis should be reconsidered for these people.

Population-based study on infant mortality.

PubMed

Lima, Jaqueline Costa; Mingarelli, Alexandre Marchezoni; Segri, Neuber José; Zavala, Arturo Alejandro Zavala; Takano, Olga Akiko

2017-03-01

Although Brazil has reduced social, economic and health indicators disparities in the last decade, intra- and inter-regional differences in child mortality rates (CMR) persist in regions such as the state capital of Mato Grosso. This population-based study aimed to investigate factors associated with child mortality in five cohorts of live births (LB) of mothers living in Cuiabá (MT), Brazil, 2006-2010, through probabilistic linkage in 47,018 LB. We used hierarchical logistic regression analysis. Of the 617 child deaths, 48% occurred in the early neonatal period. CMR ranged from 14.6 to 12.0 deaths per thousand LB. The following remained independently associated with death: mothers without companion (OR = 1.32); low number of prenatal consultations (OR = 1.65); low birthweight (OR = 4.83); prematurity (OR = 3.05); Apgar ≤ 7 at the first minute (OR = 3.19); Apgar ≤ 7 at the fifth minute (OR = 4.95); congenital malformations (OR = 14.91) and male gender (OR = 1.26). CMR has declined in Cuiabá, however, there is need to guide public healthcare policies in the prenatal and perinatal period to reduce early neonatal mortality and further studies to identify the causes of preventable deaths.

The Study of Geographic Differences in the Prevalence of Disability among Taiwanese Population

ERIC Educational Resources Information Center

Lin, Jin-Ding; Li, Chien-De; Lin, Lan-Ping; Hsu, Shang-Wei

2012-01-01

The present study analyzes data of the governmental reported general population and population of persons with disabilities from 2002 to 2009, to describe the disability prevalence and to test the overtime change with particular focused on the geographic differences in Taiwan. In average, the disability prevalence was 42.06% (range = 31.06%-80.04%…

Evaluation of the mastoid triangle for determining sexual dimorphism: A Saudi population based study.

PubMed

Madadin, Mohammed; Menezes, Ritesh G; Al Dhafeeri, Obaid; Kharoshah, Magdy A; Al Ibrahim, Rana; Nagesh, K R; Ramadan, Selma Uysal

2015-09-01

Demographic assessment of skeletal remains in forensic investigations includes identification of sex. The present study aimed to develop population-specific, sex-discriminating anthropometric standards for the mastoid triangle of a documented Saudi population using computed tomographic (CT) images of the lateral aspect of the skull. The present study was performed on 206 CT images of a documented Saudi population of known sex and age. The clinical CT images of subjects visiting the Department of Radiology, Dammam Medical Complex, Dammam, Saudi Arabia (KSA) were evaluated to know the validity of the metric assessment of the mastoid triangle for identification of sex in a Saudi population. The distance between asterion to porion (AP), asterion to mastoidale (AM), porion to mastoidale (PM) were measured and the area of the mastoid triangle (AMT) was calculated using these measurements. Discriminant function procedure was used to analyze the data for sexual dimorphism. In conclusion, the results of the present study indicate that all the 3 sides of the mastoid triangle and AMT were sexually dimorphic in the sampled Saudi population with PM being the best individual parameter in discriminating sex with an accuracy of 69.4%. Whereas, all the parameters combined showed the highest accuracy (71.4%). Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Beck Depression Inventory--II: College population study.

PubMed

O'Hara, M M; Sprinkle, S D; Ricci, N A

1998-06-01

This study expands on the normative data available for the newly revised Beck Depression Inventory-II. Data from both an outpatient, counseling-center sample (n = 152: 106 women, 46 men) and a classroom sample (n = 152: 79 women, 65 men) of college students are presented, including sex differences on the inventory. Means and standard deviations of individual items and total scores are reported, along with statistical tests of differences between groups. Comparisons of these data with norms reported by the authors of the inventory (Beck, Steer, & Brown, 1996) are offered. The lack of sex differences found in comparison of total scores for both samples is presented. Implications for the use of the inventory with college populations are discussed.

Knowledge translation within a population health study: how do you do it?

PubMed Central

2013-01-01

Background Despite the considerable and growing body of knowledge translation (KT) literature, there are few methodologies sufficiently detailed to guide an integrated KT research approach for a population health study. This paper argues for a clearly articulated collaborative KT approach to be embedded within the research design from the outset. Discussion Population health studies are complex in their own right, and strategies to engage the local community in adopting new interventions are often fraught with considerable challenges. In order to maximise the impact of population health research, more explicit KT strategies need to be developed from the outset. We present four propositions, arising from our work in developing a KT framework for a population health study. These cover the need for an explicit theory-informed conceptual framework; formalizing collaborative approaches within the design; making explicit the roles of both the stakeholders and the researchers; and clarifying what counts as evidence. From our deliberations on these propositions, our own co-creating (co-KT) Framework emerged in which KT is defined as both a theoretical and practical framework for actioning the intent of researchers and communities to co-create, refine, implement and evaluate the impact of new knowledge that is sensitive to the context (values, norms and tacit knowledge) where it is generated and used. The co-KT Framework has five steps. These include initial contact and framing the issue; refining and testing knowledge; interpreting, contextualising and adapting knowledge to the local context; implementing and evaluating; and finally, the embedding and translating of new knowledge into practice. Summary Although descriptions of how to incorporate KT into research designs are increasing, current theoretical and operational frameworks do not generally span a holistic process from knowledge co-creation to knowledge application and implementation within one project. Population

Young adults' trajectories of Ecstasy use: a population based study.

PubMed

Smirnov, Andrew; Najman, Jake M; Hayatbakhsh, Reza; Plotnikova, Maria; Wells, Helene; Legosz, Margot; Kemp, Robert

2013-11-01

Young adults' Ecstasy use trajectories have important implications for individual and population-level consequences of Ecstasy use, but little relevant research has been conducted. This study prospectively examines Ecstasy trajectories in a population-based sample. Data are from the Natural History Study of Drug Use, a retrospective/prospective cohort study conducted in Australia. Population screening identified a probability sample of Ecstasy users aged 19-23 years. Complete data for 30 months of follow-up, comprising 4 time intervals, were available for 297 participants (88.4% of sample). Trajectories were derived using cluster analysis based on recent Ecstasy use at each interval. Trajectory predictors were examined using a generalized ordered logit model and included Ecstasy dependence (World Mental Health Composite International Diagnostic Instrument), psychological distress (Hospital Anxiety Depression Scale), aggression (Young Adult Self Report) and contextual factors (e.g. attendance at electronic/dance music events). Three Ecstasy trajectories were identified (low, intermediate and high use). At its peak, the high-use trajectory involved 1-2 days Ecstasy use per week. Decreasing frequency of use was observed for intermediate and high-use trajectories from 12 months, independently of market factors. Intermediate and high-use trajectory membership was predicted by past Ecstasy consumption (>70 pills) and attendance at electronic/dance music events. High-use trajectory members were unlikely to have used Ecstasy for more than 3 years and tended to report consistently positive subjective effects at baseline. Given the social context and temporal course of Ecstasy use, Ecstasy trajectories might be better understood in terms of instrumental rather than addictive drug use patterns. © 2013 Elsevier Ltd. All rights reserved.

Alcohol consumption and cardiorespiratory fitness in five population-based studies.

PubMed

Baumeister, Sebastian E; Finger, Jonas D; Gläser, Sven; Dörr, Marcus; Markus, Marcello Rp; Ewert, Ralf; Felix, Stephan B; Grabe, Hans-Jörgen; Bahls, Martin; Mensink, Gert Bm; Völzke, Henry; Piontek, Katharina; Leitzmann, Michael F

2018-01-01

Background Poor cardiorespiratory fitness is a risk factor for cardiovascular morbidity. Alcohol consumption contributes substantially to the burden of disease, but its association with cardiorespiratory fitness is not well described. We examined associations between average alcohol consumption, heavy episodic drinking and cardiorespiratory fitness. Design The design of this study was as a cross-sectional population-based random sample. Methods We analysed data from five independent population-based studies (Study of Health in Pomerania (2008-2012); German Health Interview and Examination Survey (2008-2011); US National Health and Nutrition Examination Survey (NHANES) 1999-2000; NHANES 2001-2002; NHANES 2003-2004) including 7358 men and women aged 20-85 years, free of lung disease or asthma. Cardiorespiratory fitness, quantified by peak oxygen uptake, was assessed using exercise testing. Information regarding average alcohol consumption (ethanol in grams per day (g/d)) and heavy episodic drinking (5+ or 6+ drinks/occasion) was obtained from self-reports. Fractional polynomial regression models were used to determine the best-fitting dose-response relationship. Results Average alcohol consumption displayed an inverted U-type relation with peak oxygen uptake ( p-value<0.0001), after adjustment for age, sex, education, smoking and physical activity. Compared to individuals consuming 10 g/d (moderate consumption), current abstainers and individuals consuming 50 and 60 g/d had significantly lower peak oxygen uptake values (ml/kg/min) (β coefficients = -1.90, β = -0.06, β = -0.31, respectively). Heavy episodic drinking was not associated with peak oxygen uptake. Conclusions Across multiple adult population-based samples, moderate drinkers displayed better fitness than current abstainers and individuals with higher average alcohol consumption.

Suicidal ideation and attempts in patients with stroke: a population-based study.

PubMed

Chung, Jae Ho; Kim, Jung Bin; Kim, Ji Hyun

2016-10-01

Stroke is known to be associated with an increase in the risk for suicide. However, there are very few population-based studies investigating the risk of suicidal ideation and attempts in patients with stroke. The purpose of this study was to compare the risk of suicidal ideation and attempts between patients with stroke and population without stroke using nationwide survey data. Individual-level data were obtained from 228,735 participants (4560 with stroke and 224,175 without stroke) of the 2013 Korean Community Health Survey. Demographic characteristics, socioeconomic status, physical health status, and mental health status were compared between patients with stroke and population without stroke. Multivariable logistic regression was performed to investigate the independent effects of the stroke on suicidal ideation and attempts. Stroke patients had more depressive mood (12.6 %) than population without stroke (5.7 %, p < 0.001). Stroke patients experienced more suicidal ideation (24.4 %) and attempts (1.3 %) than population without stroke (9.8 and 0.4 %, respectively; both p < 0.001). Stroke was found to increase the risk for suicidal ideation (OR 1.65, 95 % CI 1.52-1.79) and suicidal attempts (OR 1.64, 95 % CI 1.21-2.22), adjusting for demographics, socioeconomic factors, and physical health and mental health factors. We found that stroke increased the risk for suicidal ideation and attempts, independent of other factors that are known to be associated with suicidality, suggesting that stroke per se may be an independent risk factor for suicidality.

Tools for Genetic Studies in Experimental Populations of Polyploids.

PubMed

Bourke, Peter M; Voorrips, Roeland E; Visser, Richard G F; Maliepaard, Chris

2018-01-01

Polyploid organisms carry more than two copies of each chromosome, a condition rarely tolerated in animals but which occurs relatively frequently in the plant kingdom. One of the principal challenges faced by polyploid organisms is to evolve stable meiotic mechanisms to faithfully transmit genetic information to the next generation upon which the study of inheritance is based. In this review we look at the tools available to the research community to better understand polyploid inheritance, many of which have only recently been developed. Most of these tools are intended for experimental populations (rather than natural populations), facilitating genomics-assisted crop improvement and plant breeding. This is hardly surprising given that a large proportion of domesticated plant species are polyploid. We focus on three main areas: (1) polyploid genotyping; (2) genetic and physical mapping; and (3) quantitative trait analysis and genomic selection. We also briefly review some miscellaneous topics such as the mode of inheritance and the availability of polyploid simulation software. The current polyploid analytic toolbox includes software for assigning marker genotypes (and in particular, estimating the dosage of marker alleles in the heterozygous condition), establishing chromosome-scale linkage phase among marker alleles, constructing (short-range) haplotypes, generating linkage maps, performing genome-wide association studies (GWAS) and quantitative trait locus (QTL) analyses, and simulating polyploid populations. These tools can also help elucidate the mode of inheritance (disomic, polysomic or a mixture of both as in segmental allopolyploids) or reveal whether double reduction and multivalent chromosomal pairing occur. An increasing number of polyploids (or associated diploids) are being sequenced, leading to publicly available reference genome assemblies. Much work remains in order to keep pace with developments in genomic technologies. However, such technologies

Tools for Genetic Studies in Experimental Populations of Polyploids

PubMed Central

Bourke, Peter M.; Voorrips, Roeland E.; Visser, Richard G. F.; Maliepaard, Chris

2018-01-01

Polyploid organisms carry more than two copies of each chromosome, a condition rarely tolerated in animals but which occurs relatively frequently in the plant kingdom. One of the principal challenges faced by polyploid organisms is to evolve stable meiotic mechanisms to faithfully transmit genetic information to the next generation upon which the study of inheritance is based. In this review we look at the tools available to the research community to better understand polyploid inheritance, many of which have only recently been developed. Most of these tools are intended for experimental populations (rather than natural populations), facilitating genomics-assisted crop improvement and plant breeding. This is hardly surprising given that a large proportion of domesticated plant species are polyploid. We focus on three main areas: (1) polyploid genotyping; (2) genetic and physical mapping; and (3) quantitative trait analysis and genomic selection. We also briefly review some miscellaneous topics such as the mode of inheritance and the availability of polyploid simulation software. The current polyploid analytic toolbox includes software for assigning marker genotypes (and in particular, estimating the dosage of marker alleles in the heterozygous condition), establishing chromosome-scale linkage phase among marker alleles, constructing (short-range) haplotypes, generating linkage maps, performing genome-wide association studies (GWAS) and quantitative trait locus (QTL) analyses, and simulating polyploid populations. These tools can also help elucidate the mode of inheritance (disomic, polysomic or a mixture of both as in segmental allopolyploids) or reveal whether double reduction and multivalent chromosomal pairing occur. An increasing number of polyploids (or associated diploids) are being sequenced, leading to publicly available reference genome assemblies. Much work remains in order to keep pace with developments in genomic technologies. However, such technologies

Evaluation of the contribution of D9S1120 to anthropological studies in Native American populations.

PubMed

Aguilar-Velázquez, J A; Martínez-Sevilla, V Manuel; Sosa-Macías, M; González-Martin, A; Muñoz-Valle, J F; Rangel-Villalobos, H

2017-12-01

The D9S1120 locus exhibits a population-specific allele of 9 repeats (9RA) in all Native American and two Siberian populations currently studied, but it is absent in other worldwide populations. Although this feature has been used in anthropological genetic studies, its impact on the evaluation of the structure and genetic relations among Native American populations has been scarcely assessed. Consequently, the aim of this study was to evaluate the anthropological impact of D9S1120 when it was added to STR population datasets in Mexican Native American groups. We analyzed D9S1120 by PCR and capillary electrophoresis (CE) in 1117 unrelated individuals from 13 native groups from the north and west of Mexico. Additional worldwide populations previously studied with D9S1120 and/or 15 autosomal STRs (Identifier kit) were included for interpopulation analyses. We report statistical results of forensic importance for D9S1120. On average, the modal alleles were the Native American-specific allele 9RA (0.3254) and 16 (0.3362). Genetic distances between Native American and worldwide populations were estimated. When D9S1120 was included in the 15 STR population dataset, we observed improvements for admixture estimation in Mestizo populations and for representing congruent genetic relationships in dendrograms. Analysis of molecular variance (AMOVA) based on D9S1120 confirms that most of the genetic variability in the Mexican population is attributable to their Native American backgrounds, and allows the detection of significant intercontinental differentiation attributed to the exclusive presence of 9RA in America. Our findings demonstrate the contribution of D9S1120 to a better understanding of the genetic relationships and structure among Mexican Native groups. Copyright © 2017 Elsevier GmbH. All rights reserved.

A population-based descriptive study of housefire deaths in North Carolina.

PubMed Central

Patetta, M J; Cole, T B

1990-01-01

We report a population-based study of housefire deaths in North Carolina in 1985 using data obtained from fire investigators and the North Carolina medical examiner system. The crude death rate was 3.2 per 100,000 population; age-specific death rates were highest for ages 75-84 years. Death rates for Whites were one-third as high as death rates for other races. Of those decedents tested for alcohol, 56 percent had blood alcohol levels greater than or equal to 22 mmol/L. Most fatal fires were caused by heating units or cigarettes. PMID:2382752

Population impact of familial and environmental risk factors for schizophrenia: a nationwide study.

PubMed

Sørensen, Holger J; Nielsen, Philip R; Pedersen, Carsten B; Benros, Michael E; Nordentoft, Merete; Mortensen, Preben B

2014-03-01

Although several studies have examined the relative contributions of familial and environmental risk factors for schizophrenia, few have additionally examined the predictive power on the individual level and simultaneously examined the population impact associated with a wide range of familial and environmental risk factors. The authors present rate ratios (IRR), population-attributable risks (PAR) and sex-specific cumulative incidences of the following risk factors: parental history of mental illness, urban place of birth, advanced paternal age, parental loss and immigration status. We established a population-based cohort of 2,486,646million persons born in Denmark between 1 January 1955 and 31 December 1993 using Danish registers. We found that PAR associated with urban birth was 11.73%; PAR associated with one, respectively 2, parent(s) with schizophrenia was 2.67% and 0.12%. PAR associated with second-generation immigration was 0.70%. Highest cumulative incidence (CI=20.23%; 95% CI=18.10-22.62) was found in male offspring of 2 parents with schizophrenia. Cumulative incidences for male offspring or female offspring of a parent with schizophrenia were 9.53% (95% CI=7.71-11.79), and 4.89%, (95% CI 4.50-5.31). The study showed that risk factors with highest predictive power on the individual level have a relatively low population impact. The challenge in future studies with direct genetic data is to examine gene-environmental interactions that can move research beyond current approaches and seek to achieve higher predictive power on the individual level and higher population impact. Copyright © 2014 Elsevier B.V. All rights reserved.

Atopic disorders and depression: findings from a large, population-based study.

PubMed

Sanna, Livia; Stuart, Amanda L; Pasco, Julie A; Jacka, Felice N; Berk, Michael; Maes, Michael; O'Neil, Adrienne; Girardi, Paolo; Williams, Lana J

2014-02-01

Atopy, a common disorder characterized by a sensitivity to allergic reactions, affects a large proportion of the adult population and, as with depression, is associated with immune-inflammatory pathway changes. We sought to determine the role of atopic disorders in depression using data from a randomly-selected, population-based study of men and women. Cross-sectional data derived from the Geelong Osteoporosis Study for 942 males and 1085 females were analyzed. Depression [major depressive disorder (MDD), minor depression and dysthymia] was assessed using the Structured Clinical Interview for DSM-IV-TR Research Version, Non-patient edition. Data on medical conditions, including atopic disorders (asthma, hay fever and eczema), smoking status, alcohol consumption, socioeconomic status, and physical activity were documented by self-report. Logistic regression modeling was used to explore the associations between atopic disorders and depression. Atopic disorders were associated with a 59% increased likelihood of depression [gender and smoking-adjusted odds ratio (OR) 1:50, 95% CI 1.20-1.97]. Sub-group analyses revealed a similar pattern for those with MDD [gender and smoking-adjusted OR 1:54, 95% CI 1.22-1.94]. These associations were independent of socio-demographic characteristics, clinical and lifestyle factors. Reliance on self-report for allergic symptoms and cross-sectional nature of study. This population-based study provides evidence of the potential contribution of allergic disorders to depression. Further research is required to elucidate the direction of this association and to further explicate its underlying physiology, including immune-inflammation markers. © 2013 Published by Elsevier B.V.

INNULs: A novel design amplification strategy for retrotransposable elements for studying population variation.

PubMed

LaRue, Bobby L; Sinha, Sudhir K; Montgomery, Anne H; Thompson, Robyn; Klaskala, Lauren; Ge, Jianye; King, Jonathan; Turnbough, Meredith; Budowle, Bruce

2012-01-01

Retrotransposable elements (REs), consisting of long interspersed nuclear elements (LINEs) and short interspersed nuclear elements (SINEs), are a group of markers that can be useful for human identity testing. Until now, however, due to the inherent size difference (up to 6 kb in some instances) associated with insertion and null alleles (or INNULs), the use of REs for facilitated population studies has not been sought or practical. The size of the insertion elements (from a few hundred to several thousand bp) has proven to limit their utility as a marker because of the inefficient amplicon yield with PCR. A novel primer design now facilitates INNUL marker testing. A preliminary panel of single-locus markers was developed to evaluate the potential of typing these insertion elements. Nine INNULs (5 Alu and 4 LINEs) were typed in three major North American populations and analyzed for population genetic features. In addition, the variation of each marker among the sample populations provides insight of its potential use as individual identification or ancestral marker. INNUL markers were developed into fluorescently labeled single-loci PCR. Nine markers were developed with amplicons that were less than 180 bp in length, and, depending on the locus amplicons of the INNULs, alleles varied in size from 50 to 1 bp. This allele size is noteworthy because the insertion alleles of the 9 loci range in size from 297 to 6,195 bp. The allele distribution of the INNULs was assessed and analyzed in three major North American populations. Upon observation of the distribution of the alleles in three major North American populations, the markers generally met Hardy-Weinberg expectations, and there was little evidence of detectable levels of linkage disequilibrium. Due to varying distributions of the alleles in the major population groups tested, some of the markers might be better suited for use as an individual identification marker, while others are better suited for bio

Nationwide population-based study of cause-specific death rates in patients with psoriasis.

PubMed

Salahadeen, E; Torp-Pedersen, C; Gislason, G; Hansen, P R; Ahlehoff, O

2015-05-01

Psoriasis is a common chronic disease, mediated by type 1 and 17 helper T cell-driven inflammation. Epidemiological studies have demonstrated a wide range of comorbidities and increased mortality rates. However, the current evidence on psoriasis-related mortality is limited and nationwide data have not been presented previously. In a nationwide population-based cohort we evaluated all-cause and cause-specific death rates in patients with psoriasis as compared to the general population. The entire Danish population aged 18 and above, corresponding to a total of 5,458,627 individuals (50.7% female, 40.9 years ± 19.7), including 94,069 with mild psoriasis (53% female, 42.0 ± 17.0 years) and 28,253 with severe psoriasis (53.4% female, 43.0 ± 16.5 years), was included. A total of 884,661 deaths were recorded, including 10 916 in patients with mild psoriasis and 3699 in patients with severe psoriasis. The age at time of death varied by psoriasis status, i.e. 76.5 ± 14.0, 74.4 ± 12.8 and 72.0 ± 13.4 years, for the general population, mild psoriasis and severe psoriasis respectively. In general, the highest death rates were observed in patients with severe psoriasis. Overall death rates per 1000 patient years were 13.8 [confidence interval (CI) 13.8-13.8], 17.0 (CI 16.7-17.3) and 25.4 (CI 24.6-26.3) for the general population, patients with mild psoriasis and patients with severe psoriasis respectively. This nationwide population-based study of cause-specific death rates in patients with psoriasis demonstrated reduced lifespan and increased rates of all examined specific causes of death in patients with psoriasis compared to the general population. © 2014 European Academy of Dermatology and Venereology.

Inheritance pattern of lip prints among Malay population: A pilot study.

PubMed

George, Renjith; Nora Afandi, Nurulain Syafinaz Binti; Zainal Abidin, Siti Nur Hayati Binti; Binti Ishak, Nur Ismawani; Soe, Htoo Htoo Kyaw; Ismail, Abdul Rashid Hj

2016-04-01

We assessed the resemblance of lip print patterns between parents and biological offspring in families of 31 Malay students as well as the distribution of different types of lip print in the study group. Only a few studies have successfully established the inheritance pattern of lip prints. Such studies can be population specific and need to be conducted in various populations. No such study have been conducted in Malay population in Malaysia, according to our knowledge. Present study was carried out to ascertain whether there is any inherence pattern in lip prints and thereby to investigate the potential role of lip prints in personal identification. We found 58.06% resemblance of lip print patterns between the parents and their biological offspring in our study. The influence of heredity in lip print pattern is still a new concept and there is lack of concrete evidence. The data from our study shows that there is potential influence of inheritance in the lip print patterns among the family members. Further researches involving larger samples size are suggested to derive more reliable and accurate results. The most common lip print pattern among the study group is type I (29.84%) followed by type II (23.12%), type III (22.45%), type I' (13.44%), type IV (9.54%) and type V (1.61%). Racial variations in lip print patterns and their prevalence may serve as an aid in forensic identification and crime scene investigation. The results of this pilot study will help in establishing guidelines for future researches on lip print analysis in Malaysia. Lip print patterns are unique and individualistic. However, there are some similarities in basic patterns of lip prints between family members which may be attributed to influence of inheritance. 1. To determine the inheritance pattern of lip prints among Malay family members of the student. 2. To identify the distribution of different types of lip prints among Malay population. and Observational pilot study. Lip prints of 124

Oral mucosal lesions and risk habits among men in an Italian study population.

PubMed

Campisi, G; Margiotta, V

2001-01-01

A randomly selected study population of 118 male subjects (> or = 40 years) living on the Mediterranean island of Pantelleria (southwest of Sicily, Italy) was examined for the presence of oral mucosal lesions, with particular emphasis on the early diagnosis of oral precancerous and cancerous lesions. The study population was interviewed for socioeconomic and behavioural information, and clinically examined using WHO criteria. The prevalence of oral mucosal lesions observed, and data obtained about oral hygiene, tobacco smoking, alcohol drinking and exposure to actinic radiation, were analysed. Alcohol drinking was the most common habit in the study population (73%), followed by tobacco smoking (58.5%, of whom 96% were cigarette smokers). Only 3% showed good oral hygiene and 25% were edentate. Oral lesions were observed in 81.3% of the study group, mainly coated tongue (51.4%), leukoplakia (13.8%), traumatic oral lesions (traumatic ulcers and frictional white lesions) in 9.2%, actinic cheilitis (4.6%), and squamous cell carcinoma in one case (0.9%). Statistically significant associations were found between the prevalence of coated tongue and tobacco smoking (P<0.0001), and between the prevalence of actinic cheilitis and tobacco smoking/alcohol drinking (P<0.05). Analysis of clinical and anamnestic data underlined the effective presence, in the population examined, of the behavioural risk factors for oral precancerous and cancerous lesions, and the lack of cultural motivation towards primary prevention activities, such as the elimination of risk habits.

Sequencing Strategies for Population and Cancer Epidemiology Studies (SeqSPACE) Webinar Series

Cancer.gov

The Sequencing Strategies for Population and Cancer Epidemiology Studies (SeqSPACE) Webinar Series provides an opportunity for our grantees and other interested individuals to share lessons learned and practical information regarding the application of next generation sequencing to cancer epidemiology studies.

Simulating a base population in honey bee for molecular genetic studies.

PubMed

Gupta, Pooja; Conrad, Tim; Spötter, Andreas; Reinsch, Norbert; Bienefeld, Kaspar

2012-06-27

Over the past years, reports have indicated that honey bee populations are declining and that infestation by an ecto-parasitic mite (Varroa destructor) is one of the main causes. Selective breeding of resistant bees can help to prevent losses due to the parasite, but it requires that a robust breeding program and genetic evaluation are implemented. Genomic selection has emerged as an important tool in animal breeding programs and simulation studies have shown that it yields more accurate breeding value estimates, higher genetic gain and low rates of inbreeding. Since genomic selection relies on marker data, simulations conducted on a genomic dataset are a pre-requisite before selection can be implemented. Although genomic datasets have been simulated in other species undergoing genetic evaluation, simulation of a genomic dataset specific to the honey bee is required since this species has a distinct genetic and reproductive biology. Our software program was aimed at constructing a base population by simulating a random mating honey bee population. A forward-time population simulation approach was applied since it allows modeling of genetic characteristics and reproductive behavior specific to the honey bee. Our software program yielded a genomic dataset for a base population in linkage disequilibrium. In addition, information was obtained on (1) the position of markers on each chromosome, (2) allele frequency, (3) χ(2) statistics for Hardy-Weinberg equilibrium, (4) a sorted list of markers with a minor allele frequency less than or equal to the input value, (5) average r(2) values of linkage disequilibrium between all simulated marker loci pair for all generations and (6) average r2 value of linkage disequilibrium in the last generation for selected markers with the highest minor allele frequency. We developed a software program that takes into account the genetic and reproductive biology specific to the honey bee and that can be used to constitute a genomic

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

Baseline studies of health status in north Atlantic Baleen whale populations

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

Lambertsen, R.H.

1988-09-01

This study investigated the health status of fin and sei whale populations of the central North Atlantic to establish a baseline for comparison with stranded whales in more heavily contaminated coastal zones. Systematic necropsy examinations were conducted on 150 fin whales and 42 sei whales caught by commercial whalers off the west coast of Iceland. Gas chromatographic measurements showed detectable tissue levels of organochlorine pesticides, but these levels were low, ranging from 0.2 ppb (gamma-BHC) to 1540 ppb (p,p{prime} DDE). Relevant to the comparative evaluation of contaminant effects was the finding that both the fin and sei whale, despite verymore » similar life histories, suffered from a distinct complement of natural disease problems. From the high incidence and contaminative route of transmission of the major parasitic diseases found, it is predicted that population-level health effects, including increments in mortality rate potentially caused by environmental contamination, will increase with population density.« less

[Results of a cytogenetic study of populations with different radiation risks in the Semipalatinsk region].

PubMed

Sviatova, G S; Abil'dinova, G Z; Berezina, G M

2002-03-01

A cytogenetic study was conducted for the first time on human populations neighboring the Semipalatinsk nuclear test site (STS) and exposed to ionizing radiation for a long period of time. In populations with the extreme and maximum radiation risks, high frequencies of radiation-induced chromosomal markers, including acentric fragments (1.99 +/- 0.10 per 100 cells), dicentrics (0.23 +/- 0.01), ring chromosomes (0.38 +/- 0.14), and stable chromosomal aberrations (1.17 +/- 0.02), were found. These frequencies significantly exceeded those in control populations. The spectrum of chromosomal aberrations and the frequencies of the aberrations of different types in persons living in the areas with the highest radionuclide contamination confirmed the mutagenic effect of radiation on chromosomes in the human populations studied.

A Population-Based Approach to Study the Impact of PROP Perception on Food Liking in Populations along the Silk Road

PubMed Central

Robino, Antonietta; Mezzavilla, Massimo; Pirastu, Nicola; Dognini, Maddalena; Tepper, Beverly J.; Gasparini, Paolo

2014-01-01

Taste is one of the main factors determining food choices. Differences in PROP bitter taste perception have been implicated in individual differences in food preferences and selection. The present study examined associations between, PROP phenotypes, self-reported food liking and TAS2R38 polymorphisms, the major gene implicated in PROP bitterness, in six different populations of the Caucasus and Central Asia, located along the ancient Silk Road. Differences in the distribution of PROP phenotypes across populations were detected, with a higher frequency of super tasters in Tajikistan (31.3%) and Armenia (39.0%) and a higher frequency of non tasters in Georgia (50.9%). While no relationships were observed between PROP phenotypes and food liking using standard statistical tests, we used an approach based on comparison of distance matrices derived from these data. The first matrix compared the food liking ratings of each population to all others pairwise using the Kruskal-Wallis test (at p<0.00063), and the second one compared the distribution of PROP phenotypes across all populations in a similar manner calculating the chi-square statistic as a distance measure. A strong correlation between the two matrices was found (Mantel test: r = 0.67, p-value = 0.03), suggesting that the pattern of food liking across populations was closely related to the distribution of PROP phenotypes. This same relationship was not observed when TAS2R38 genotypes were substituted for PROP phenotypes in this analysis. Our data suggest that a population-based approach utilizing distance matrices is a useful technique for detecting PROP-related differences in food liking and can be applied to other taste phenotypes. PMID:24626196

A population-based approach to study the impact of PROP perception on food liking in populations along the Silk Road.

PubMed

Robino, Antonietta; Mezzavilla, Massimo; Pirastu, Nicola; Dognini, Maddalena; Tepper, Beverly J; Gasparini, Paolo

2014-01-01

Taste is one of the main factors determining food choices. Differences in PROP bitter taste perception have been implicated in individual differences in food preferences and selection. The present study examined associations between, PROP phenotypes, self-reported food liking and TAS2R38 polymorphisms, the major gene implicated in PROP bitterness, in six different populations of the Caucasus and Central Asia, located along the ancient Silk Road. Differences in the distribution of PROP phenotypes across populations were detected, with a higher frequency of super tasters in Tajikistan (31.3%) and Armenia (39.0%) and a higher frequency of non tasters in Georgia (50.9%). While no relationships were observed between PROP phenotypes and food liking using standard statistical tests, we used an approach based on comparison of distance matrices derived from these data. The first matrix compared the food liking ratings of each population to all others pairwise using the Kruskal-Wallis test (at p<0.00063), and the second one compared the distribution of PROP phenotypes across all populations in a similar manner calculating the chi-square statistic as a distance measure. A strong correlation between the two matrices was found (Mantel test: r = 0.67, p-value = 0.03), suggesting that the pattern of food liking across populations was closely related to the distribution of PROP phenotypes. This same relationship was not observed when TAS2R38 genotypes were substituted for PROP phenotypes in this analysis. Our data suggest that a population-based approach utilizing distance matrices is a useful technique for detecting PROP-related differences in food liking and can be applied to other taste phenotypes.

Economic Impact of Dyspepsia in Rural and Urban Malaysia: A Population-Based Study

PubMed Central

Yadav, Hematram; Everett, Simon M; Goh, Khean-Lee

2012-01-01

Background/Aims The economic impact of dyspepsia in regions with a diverse healthcare system remains uncertain. This study aimed to estimate the costs of dyspepsia in a rural and urban population in Malaysia. Methods Economic evaluation was performed based on the cost-of-illness method. Resource utilization and quality of life data over a specific time frame, were collected to determine direct, indirect and intangible costs related to dyspepsia. Results The prevalences of dyspepsia in the rural (n = 2,000) and urban (n = 2,039) populations were 14.6% and 24.3% respectively. Differences in socioeconomic status and healthcare utilisation between both populations were considerable. The cost of dyspepsia per 1,000 population per year was estimated at USD14,816.10 and USD59,282.20 in the rural and urban populations respectively. The cost per quality adjusted life year for dyspepsia in rural and urban adults was USD16.30 and USD69.75, respectively. Conclusions The economic impact of dyspepsia is greater in an urban compared to a rural setting. Differences in socioeconomic status and healthcare utilisation between populations are thought to contribute to this difference. PMID:22323987

Field Studies Reveal Strong Postmating Isolation between Ecologically Divergent Butterfly Populations

PubMed Central

McBride, Carolyn S.; Singer, Michael C.

2010-01-01

Gene flow between populations that are adapting to distinct environments may be restricted if hybrids inherit maladaptive, intermediate phenotypes. This phenomenon, called extrinsic postzygotic isolation (EPI), is thought to play a critical role in the early stages of speciation. However, despite its intuitive appeal, we know surprisingly little about the strength and prevalence of EPI in nature, and even less about the specific phenotypes that tend to cause problems for hybrids. In this study, we searched for EPI among allopatric populations of the butterfly Euphydryas editha that have specialized on alternative host plants. These populations recall a situation thought typical of the very early stages of speciation. They lack consistent host-associated genetic differentiation at random nuclear loci and show no signs of reproductive incompatibility in the laboratory. However, they do differ consistently in diverse host-related traits. For each of these traits, we first asked whether hybrids between populations that use different hosts (different-host hybrids) were intermediate to parental populations and to hybrids between populations that use the same host (same-host hybrids). We then conducted field experiments to estimate the effects of intermediacy on fitness in nature. Our results revealed strong EPI under field conditions. Different-host hybrids exhibited an array of intermediate traits that were significantly maladaptive, including four behaviors. Intermediate foraging height slowed the growth of larvae, while intermediate oviposition preference, oviposition site height, and clutch size severely reduced the growth and survival of the offspring of adult females. We used our empirical data to construct a fitness surface on which different-host hybrids can be seen to fall in an adaptive valley between two peaks occupied by same-host hybrids. These findings demonstrate how ecological selection against hybrids can create a strong barrier to gene flow at the early

Variation in genetic admixture and population structure among Latinos: the Los Angeles Latino eye study (LALES)

PubMed Central

2009-01-01

Background Population structure and admixture have strong confounding effects on genetic association studies. Discordant frequencies for age-related macular degeneration (AMD) risk alleles and for AMD incidence and prevalence rates are reported across different ethnic groups. We examined the genomic ancestry characterizing 538 Latinos drawn from the Los Angeles Latino Eye Study [LALES] as part of an ongoing AMD-association study. To help assess the degree of Native American ancestry inherited by Latino populations we sampled 25 Mayans and 5 Mexican Indians collected through Coriell's Institute. Levels of European, Asian, and African descent in Latinos were inferred through the USC Multiethnic Panel (USC MEP), formed from a sample from the Multiethnic Cohort (MEC) study, the Yoruba African samples from HapMap II, the Singapore Chinese Health Study, and a prospective cohort from Shanghai, China. A total of 233 ancestry informative markers were genotyped for 538 LALES Latinos, 30 Native Americans, and 355 USC MEP individuals (African Americans, Japanese, Chinese, European Americans, Latinos, and Native Hawaiians). Sensitivity of ancestry estimates to relative sample size was considered. Results We detected strong evidence for recent population admixture in LALES Latinos. Gradients of increasing Native American background and of correspondingly decreasing European ancestry were observed as a function of birth origin from North to South. The strongest excess of homozygosity, a reflection of recent population admixture, was observed in non-US born Latinos that recently populated the US. A set of 42 SNPs especially informative for distinguishing between Native Americans and Europeans were identified. Conclusion These findings reflect the historic migration patterns of Native Americans and suggest that while the 'Latino' label is used to categorize the entire population, there exists a strong degree of heterogeneity within that population, and that it will be important to

Variation in genetic admixture and population structure among Latinos: the Los Angeles Latino eye study (LALES).

PubMed

Shtir, Corina J; Marjoram, Paul; Azen, Stanley; Conti, David V; Le Marchand, Loic; Haiman, Christopher A; Varma, Rohit

2009-11-10

Population structure and admixture have strong confounding effects on genetic association studies. Discordant frequencies for age-related macular degeneration (AMD) risk alleles and for AMD incidence and prevalence rates are reported across different ethnic groups. We examined the genomic ancestry characterizing 538 Latinos drawn from the Los Angeles Latino Eye Study [LALES] as part of an ongoing AMD-association study. To help assess the degree of Native American ancestry inherited by Latino populations we sampled 25 Mayans and 5 Mexican Indians collected through Coriell's Institute. Levels of European, Asian, and African descent in Latinos were inferred through the USC Multiethnic Panel (USC MEP), formed from a sample from the Multiethnic Cohort (MEC) study, the Yoruba African samples from HapMap II, the Singapore Chinese Health Study, and a prospective cohort from Shanghai, China. A total of 233 ancestry informative markers were genotyped for 538 LALES Latinos, 30 Native Americans, and 355 USC MEP individuals (African Americans, Japanese, Chinese, European Americans, Latinos, and Native Hawaiians). Sensitivity of ancestry estimates to relative sample size was considered. We detected strong evidence for recent population admixture in LALES Latinos. Gradients of increasing Native American background and of correspondingly decreasing European ancestry were observed as a function of birth origin from North to South. The strongest excess of homozygosity, a reflection of recent population admixture, was observed in non-US born Latinos that recently populated the US. A set of 42 SNPs especially informative for distinguishing between Native Americans and Europeans were identified. These findings reflect the historic migration patterns of Native Americans and suggest that while the 'Latino' label is used to categorize the entire population, there exists a strong degree of heterogeneity within that population, and that it will be important to assess this heterogeneity

Factors Associated with Physical Inactivity among Adult Urban Population of Puducherry, India: A Population Based Cross-sectional Study.

PubMed

Newtonraj, Ariarathinam; Murugan, Natesan; Singh, Zile; Chauhan, Ramesh Chand; Velavan, Anandan; Mani, Manikandan

2017-05-01

Physical inactivity is the fourth leading cause of death worldwide. Increase in physical activity decreases the incidence of cardiovascular diseases, Type 2 diabetes, stroke, and improves psychological wellbeing. To study the level of physical inactivity among the adult population in an urban area of Puducherry in India and its associated risk factors. This cross-sectional study was conducted among 569 adult participants from an urban area of Pondicherry. The level of physical inactivity was measured by using WHO standard Global Physical Activity Questionnaire (GPAQ). Overall prevalence of physical inactivity in our study was 49.7% (CI: 45.6-53.8). Among the physically active people, contribution of physical activity by work was 77.4%, leisure time activities were 11.6% and transport time was 11%. Both men and women were equally inactive {Physically inactive among women was 50% (CI:44.1-55.9)} and {Physically inactive among men was 49.5% (CI:43.8-55.2)}. Prevalence of physical inactivity was increasing with increasing age. Non tobacco users were two times more active than tobacco users {Adjusted Odds Ratio: 2.183 (1.175- 4.057)}. Employed were more active as compared to retired {Adjusted Odds Ratio: 0.412 (0.171-0.991)}, students {Adjusted Odds Ratio: 0.456 (0.196-1.060)}, house wives {Adjusted Odds Ratio: 0.757 (0.509-1.127)} and unemployed {Adjusted Odds Ratio: 0.538 (0.271-1.068)}. Non alcoholics were only 0.34 times as active as alcoholics. Level of physical activity was found to be insufficient among adult urban population of Puducherry. Working adult population found to be active, that too due to their work pattern. There is a need to promote leisure time and travelling time physical activity.

Linguistic, geographic and genetic isolation: a collaborative study of Italian populations.

PubMed

Capocasa, Marco; Anagnostou, Paolo; Bachis, Valeria; Battaggia, Cinzia; Bertoncini, Stefania; Biondi, Gianfranco; Boattini, Alessio; Boschi, Ilaria; Brisighelli, Francesca; Caló, Carla Maria; Carta, Marilisa; Coia, Valentina; Corrias, Laura; Crivellaro, Federica; De Fanti, Sara; Dominici, Valentina; Ferri, Gianmarco; Francalacci, Paolo; Franceschi, Zelda Alice; Luiselli, Donata; Morelli, Laura; Paoli, Giorgio; Rickards, Olga; Robledo, Renato; Sanna, Daria; Sanna, Emanuele; Sarno, Stefania; Sineo, Luca; Taglioli, Luca; Tagarelli, Giuseppe; Tofanelli, Sergio; Vona, Giuseppe; Pettener, Davide; Destro Bisol, Giovanni

2014-01-01

The animal and plant biodiversity of the Italian territory is known to be one of the richest in the Mediterranean basin and Europe as a whole, but does the genetic diversity of extant human populations show a comparable pattern? According to a number of studies, the genetic structure of Italian populations retains the signatures of complex peopling processes which took place from the Paleolithic to modern era. Although the observed patterns highlight a remarkable degree of genetic heterogeneity, they do not, however, take into account an important source of variation. In fact, Italy is home to numerous ethnolinguistic minorities which have yet to be studied systematically. Due to their difference in geographical origin and demographic history, such groups not only signal the cultural and social diversity of our country, but they are also potential contributors to its bio-anthropological heterogeneity. To fill this gap, research groups from four Italian Universities (Bologna, Cagliari, Pisa and Roma Sapienza) started a collaborative study in 2007, which was funded by the Italian Ministry of Education, University and Research and received partial support by the Istituto Italiano di Antropologia. In this paper, we present an account of the results obtained in the course of this initiative. Four case-studies relative to linguistic minorities from the Eastern Alps, Sardinia, Apennines and Southern Italy are first described and discussed, focusing on their micro-evolutionary and anthropological implications. Thereafter, we present the results of a systematic analysis of the relations between linguistic, geographic and genetic isolation. Integrating the data obtained in the course of the long-term study with literature and unpublished results on Italian populations, we show that a combination of linguistic and geographic factors is probably responsible for the presence of the most robust signatures of genetic isolation. Finally, we evaluate the magnitude of the diversity

A multi-scale study of Orthoptera species richness and human population size controlling for sampling effort

NASA Astrophysics Data System (ADS)

Cantarello, Elena; Steck, Claude E.; Fontana, Paolo; Fontaneto, Diego; Marini, Lorenzo; Pautasso, Marco

2010-03-01

Recent large-scale studies have shown that biodiversity-rich regions also tend to be densely populated areas. The most obvious explanation is that biodiversity and human beings tend to match the distribution of energy availability, environmental stability and/or habitat heterogeneity. However, the species-people correlation can also be an artefact, as more populated regions could show more species because of a more thorough sampling. Few studies have tested this sampling bias hypothesis. Using a newly collated dataset, we studied whether Orthoptera species richness is related to human population size in Italy’s regions (average area 15,000 km2) and provinces (2,900 km2). As expected, the observed number of species increases significantly with increasing human population size for both grain sizes, although the proportion of variance explained is minimal at the provincial level. However, variations in observed Orthoptera species richness are primarily associated with the available number of records, which is in turn well correlated with human population size (at least at the regional level). Estimated Orthoptera species richness (Chao2 and Jackknife) also increases with human population size both for regions and provinces. Both for regions and provinces, this increase is not significant when controlling for variation in area and number of records. Our study confirms the hypothesis that broad-scale human population-biodiversity correlations can in some cases be artefactual. More systematic sampling of less studied taxa such as invertebrates is necessary to ascertain whether biogeographical patterns persist when sampling effort is kept constant or included in models.

Prevalence of refractive errors in a Brazilian population: the Botucatu eye study.

PubMed

Schellini, Silvana Artioli; Durkin, Shane R; Hoyama, Erika; Hirai, Flavio; Cordeiro, Ricardo; Casson, Robert J; Selva, Dinesh; Padovani, Carlos Roberto

2009-01-01

To determine the prevalence and demographic associations of refractive error in Botucatu, Brazil. A population-based, cross-sectional prevalence study was conducted, which involved random, household cluster sampling of an urban Brazilian population in Botucatu. There were 3000 individuals aged 1 to 91 years (mean 38.3) who were eligible to participate in the study. Refractive error measurements were obtained by objective refraction. Objective refractive error examinations were performed on 2454 residents within this sample (81.8% of eligible participants). The mean age was 38 years (standard deviation (SD) 20.8 years, Range 1 to 91) and females comprised 57.5% of the study population. Myopia (spherical equivalent (SE) < -0.5 dropters (D)) was most prevalent among those aged 30-39 years (29.7%; 95% confidence interval (CI) 24.8-35.1) and least prevalent among children under 10 years (3.8%; 95% confidence interval (CI) 1.6-7.3). Conversely hypermetropia (SE > 0.5D) was most prevalent among participants under 10 years (86.9%; 95% CI 81.6-91.1) and least prevalent in the fourth decade (32.5%; 95% CI 28.2-37.0). Participants aged 70 years or older bore the largest burden of astigmatism (cylinder at least -0.5D) and anisometropia (difference in SE of > 0.5D) with a prevalence of 71.7% (95% CI 64.8-78.0) 55.0% (95% CI 47.6-62.2) respectively. Myopia and hypermetropia were significantly associated with age in a bimodal manner (P < 0.001), whereas anisometropia and astigmatism increased in line with age (P < 0.001). Multivariate modeling confirmed age-related risk factors for refractive error and revealed several gender, occupation and ethnic-related risk factors. These results represent previously unreported data on refractive error within this Brazilian population. They signal a need to continue to screen for refractive error within this population and to ensure that people have adequate access to optical correction.

Results for five sets of forensic genetic markers studied in a Greek population sample.

PubMed

Tomas, C; Skitsa, I; Steinmeier, E; Poulsen, L; Ampati, A; Børsting, C; Morling, N

2015-05-01

A population sample of 223 Greek individuals was typed for five sets of forensic genetic markers with the kits NGM SElect™, SNPforID 49plex, DIPplex®, Argus X-12 and PowerPlex® Y23. No significant deviation from Hardy-Weinberg expectations was observed for any of the studied markers after Holm-Šidák correction. Statistically significant (P<0.05) levels of linkage disequilibrium were observed between markers within two of the studied X-chromosome linkage groups. AMOVA analyses of the five sets of markers did not show population structure when the individuals were grouped according to their geographic origin. The Greek population grouped closely to the other European populations measured by F(ST)(*) distances. The match probability ranged from a value of 1 in 2×10(7) males by using haplotype frequencies of four X-chromosome haplogroups in males to 1 in 1.73×10(21) individuals for 16 autosomal STRs. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Predictors of Cerebral Palsy in Very Preterm Infants: The EPIPAGE Prospective Population-Based Cohort Study

ERIC Educational Resources Information Center

Beaino, Ghada; Khoshnood, Babak; Kaminski, Monique; Pierrat, Veronique; Marret, Stephane; Matis, Jacqueline; Ledesert, Bernard; Thiriez, Gerard; Fresson, Jeanne; Roze, Jean-Christophe; Zupan-Simunek, Veronique; Arnaud, Catherine; Burguet, Antoine; Larroque, Beatrice; Breart, Gerard; Ancel, Pierre-Yves

2010-01-01

Aim: The aim of this study was to assess the independent role of cerebral lesions on ultrasound scan, and several other neonatal and obstetric factors, as potential predictors of cerebral palsy (CP) in a large population-based cohort of very preterm infants. Method: As part of EPIPAGE, a population-based prospective cohort study, perinatal data…

Anthropometric growth study of the ear in a Chinese population.

PubMed

Zhao, Shichun; Li, Dianguo; Liu, Zhenzhong; Wang, Yibiao; Liu, Lei; Jiang, Duyin; Pan, Bo

2018-04-01

A large number of anthropometric studies of the auricle have been reported in different nations, but little data were available in the Chinese population. The aim of this study was to analyze growth changes in the ear by measuring the width and length of ears in a Chinese population. A total of 480 participants were enrolled and classified into 1-, 3-, 5-, 7-, 9-, 12-, 14-, and 18-year groups (half were boys and half were girls in each group). Ear length, ear width, body weight, and body length were measured and recorded; ear index was calculated according to ear length and ear width. The growth of auricle and differences between genders were analyzed. Growth of ear in relation to body height and weight and the degree of emphasis on the length and width of the auricle were also analyzed. Ear length and width increased with age. Ear length achieved its mature size in both 14-year-old males and females. Ear width reached its mature size in males at 7 years and in females at 5 years. Different trends of ear index were shown between males and females. People in this population paid more attention to the length than the width of the auricle. The data indicated that ear development followed increase in age. There were gender and ethnic difference in the development of ear. These results may have potential implications for the diagnosis of congenital malformations, syndromes, and planning of ear reconstruction surgery. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Hippocampal atrophy in people with memory deficits: results from the population-based IPREA study.

PubMed

Ferrarini, Luca; van Lew, Baldur; Reiber, Johan H C; Gandin, Claudia; Galluzzo, Lucia; Scafato, Emanuele; Frisoni, Giovanni B; Milles, Julien; Pievani, Michela

2014-07-01

Clinical studies have shown that hippocampal atrophy is present before dementia in people with memory deficits and can predict dementia development. The question remains whether this association holds in the general population. This is of interest for the possible use of hippocampal atrophy to screen population for preventive interventions. The aim of this study was to assess hippocampal volume and shape abnormalities in elderly adults with memory deficits in a cross-sectional population-based study. We included individuals participating in the Italian Project on the Epidemiology of Alzheimer Disease (IPREA) study: 75 cognitively normal individuals (HC), 31 individuals with memory deficits (MEM), and 31 individuals with memory deficits not otherwise specified (MEMnos). Hippocampal volumes and shape were extracted through manual tracing and the growing and adaptive meshes (GAMEs) shape-modeling algorithm. We investigated between-group differences in hippocampal volume and shape, and correlations with memory deficits. In MEM participants, hippocampal volumes were significantly smaller than in HC and were mildly associated with worse memory scores. Memory-associated shape changes mapped to the anterior hippocampus. Shape-based analysis detected no significant difference between MEM and HC, while MEMnos showed shape changes in the posterior hippocampus compared with HC and MEM groups. These findings support the discriminant validity of hippocampal volumetry as a biomarker of memory impairment in the general population. The detection of shape changes in MEMnos but not in MEM participants suggests that shape-based biomarkers might lack sensitivity to detect Alzheimer's-like pathology in the general population.

[Population genetics study of functional brain asymmetry in the native and immigrant populations of northeastern USSR. I. Sex-age distribution and familial data].

PubMed

Solovenchuk, L L; Arshavskiĭ, V V

1988-05-01

Clearly definable polymorphism of hemisphere interrelations represented by three phenotypes was established by the method of EEG cross-correlation analysis. Each phenotype of the three, representing polymorphism, is characterized by marked specificity of perception and the processing of information, which determines certain integral physiological characteristics of individuals. Phenotype frequencies in aboriginal and new-come populations of the North-East of the USSR differ significantly. In comparison with the inhabitants, Moscow Russians of Magadan are significantly closer to aboriginal population, judging by their frequency distribution, and this may be due to the strategy specificity in adaptation of populations to environmental conditions. Significant difference in phenotype frequencies is shown in representatives of both sexes, this being more pronounced in the aboriginal population. The establishment of interhemispheric reaction type by approx. 10th year of individual's life is confirmed. Phenotype frequency correlations, depending on parental phenotype, were analyzed in children. The role of genetic and environmental factors in manifestation of the hemisphere relationship type is discussed. Rationality of the population analysis of hemisphere asymmetry types is grounded, according to the study of behavioural genetics and population adaptation.

Incorporation of inorganic mercury (Hg2+) in pelagic food webs of ultraoligotrophic and oligotrophic lakes: the role of different plankton size fractions and species assemblages

USGS Publications Warehouse

Soto Cárdenas, Carolina; Diéguez, Maria C.; Ribeiro Guevara, Sergio; Marvin-DiPasquale, Mark; Queimaliños, Claudia P.

2014-01-01

In lake food webs, pelagic basal organisms such as bacteria and phytoplankton incorporate mercury (Hg2+) from the dissolved phase and pass the adsorbed and internalized Hg to higher trophic levels. This experimental investigation addresses the incorporation of dissolved Hg2+ by four plankton fractions (picoplankton: 0.2–2.7 μm; pico + nanoplankton: 0.2–20 μm; microplankton: 20–50 μm; and mesoplankton: 50–200 μm) obtained from four Andean Patagonian lakes, using the radioisotope 197Hg2+. Species composition and abundance were determined in each plankton fraction. In addition, morphometric parameters such as surface and biovolume were calculated using standard geometric models. The incorporation of Hg2+ in each plankton fraction was analyzed through three concentration factors: BCF (bioconcentration factor) as a function of cell or individual abundance, SCF (surface concentration factor) and VCF (volume concentration factor) as functions of individual exposed surface and biovolume, respectively. Overall, this investigation showed that through adsorption and internalization, pico + nanoplankton play a central role leading the incorporation of Hg2+ in pelagic food webs of Andean lakes. Larger planktonic organisms included in the micro- and mesoplankton fractions incorporate Hg2+ by surface adsorption, although at a lesser extent. Mixotrophic bacterivorous organisms dominate the different plankton fractions of the lakes connecting trophic levels through microbial loops (e.g., bacteria–nanoflagellates–crustaceans; bacteria–ciliates–crustaceans; endosymbiotic algae–ciliates). These bacterivorous organisms, which incorporate Hg from the dissolved phase and through their prey, appear to explain the high incorporation of Hg2+ observed in all the plankton fractions.

Clinical characteristics of an Afrikaner founder population recruited for a schizophrenia genetic study.

PubMed

Roos, Johannes Lodewikus; Pretorius, Herman Walter; Karayiorgou, Maria

2009-01-01

The clinical characteristics of an Afrikaner founder population sample recruited for a schizophrenia genetic study are described. Comparisons on several clinical characteristics between this sample and a U.S. sample of schizophrenia patients show that generalization of findings in a founder population to the population at large is applicable. The assessment of the frequency of the 22q11 deletion in Afrikaner schizophrenia patients is approximately 2%, similar to findings in a U.S. sample. Results of analysis of early non-psychotic deviant behavior in subjects under the age of 10 years in the Afrikaner population broadly replicated findings in a U.S. sample. Approximately half of male schizophrenia patients and a quarter of female patients in the Afrikaner schizophrenia database used or abused cannabis. Male users of cannabis with severe early deviant behavior had the lowest mean age of criteria onset, namely 18.4 years. These findings confirm previous findings, indicating that early deviance is linked to later outcome of disease. The clinical characteristics and premorbid variables in 12 childhood-onset Afrikaner schizophrenia patients thus far recruited in this study compare favorably with what is known about childhood-onset schizophrenia in a U.S. sample. The prevalence of co-morbid OCD/OCS in this Afrikaner schizophrenia founder sample was 13.2% which is in keeping with that of co-morbid OCD in schizophrenia, estimated at 12.2% by the U.S. National Institute of Mental Health. These findings confirm that the clinical characteristics of a schizophrenia sample drawn from the Afrikaner founder population can be generalized to the schizophrenia population at large when compared to findings reported in the literature.

An assessment study of CVD related risk factors in a tribal population of India.

PubMed

Kandpal, Vani; Sachdeva, M P; Saraswathy, K N

2016-05-25

Non communicable diseases (NCDs) have become a major concern for global health. Cardiovascular diseases (CVDs) contribute 48 % towards the deaths due to NCDs in India. Though studies have been conducted in urban and rural areas, data related to tribal communities is limited. The present study aims to examine various CVD related risk factors including hypertension, elevated fasting blood glucose, obesity and metabolic syndrome among a tribal population. The present study was an observational, cross- sectional study conducted on Rang Bhotias, a tribal population of India. The participants were adults of age between 20 and 60 years. Prior to blood sample collection, interview schedule was administered which included relevant information like age, lifestyle, socio-economic status, education and occupation In addition to this, various anthropometric and physiological measurements were taken. Logistic regression was used to examine the association of the various health disorders related to CVDs with age, gender and behavioural factors (smoking, alcohol consumption and physical activity). A total of 288 participants were surveyed for the study including 104 males and 184 females. High BMI (56.6 %), hypertension (43.4 %), metabolic syndrome (39.2 %) and abdominal obesity (33.7 %) were the most prevalent CVD risk factors observed in the population. The multivariate logistic regression analysis, conducted to examine the contribution of risk factors including behavioural risk factors on the studied abnormalities, revealed age to be a significant risk factor for all the abnormalities except elevated fasting blood glucose. Gender and physical inactivity contributed significantly towards development of hypertension. Physical inactivity was also found to be associated with high BMI levels. In the present study, hypertension, high BMI levels, MS and abdominal obesity have been found to be high among the studied population. The status of the population with respect to these

Distribution of Brazilian dermatologists according to geographic location, population and HDI of municipalities: an ecological study*

PubMed Central

Schmitt, Juliano Vilaverde; Miot, Hélio Amante

2014-01-01

This study investigated the geographic distribution of dermatologists in Brazilian municipalities in relation to the population, regions of the country and human development index. We conducted an ecological study based on data from the 2010 census, the 2010 human development index, and the records of the Brazilian Society of Dermatology. 5565 municipalities and 6718 dermatologists were surveyed. Only 504 (9.1%) municipalities had dermatologists, and accounted for 56.2% of the Brazilian population. The smallest population size and lowest HDI rate that best discriminated municipalities that did not have dermatologists were found to be 28,000 and 0.71, respectively. The average population density of dermatologists in cities was 1/23.000 inhabitants, and variations were independently associated with the HDI, the population of the municipalities and the region of the country. PMID:25387516

RESPIRATORY DOSE TO SUSCEPTIBLE POPULATIONS ASSESSED BY EXPOSURE AND DOSIMETRY STUDIES

EPA Science Inventory

Respiratory Dose to Susceptible Populations Assessed by Exposure and Dosimetry Studies

Chong Kim1 and Ronald Williams2, 1USEPA National Health and Environmental Effects Research Laboratory and 2USEPA National Exposure Research Laboratory, RTP, NC.

Rationale: Parti...

Natural history of heartburn: A 10-year population-based study

PubMed Central

Olafsdottir, Linda Bjork; Gudjonsson, Hallgrimur; Jonsdottir, Heidur Hrund; Thjodleifsson, Bjarni

2011-01-01

AIM: To study the natural history and prevalence of heartburn at a 10-year interval, and to study the effect of heartburn on various symptoms and activities. METHODS: A population-based postal study was carried out. Questionnaires were mailed to the same age- and gender-stratified random sample of the Icelandic population (aged 18-75 years) in 1996 and again in 2006. Subjects were classified with heartburn if they reported heartburn in the preceding year and/or week, based on the definition of heartburn. RESULTS: Heartburn in the preceding year was reported in 42.8% (1996) and 44.2% (2006) of subjects, with a strong relationship between those who experienced heartburn in both years. Heartburn in the preceding week was diagnosed in 20.8%. There was a significant relationship between heartburn, dyspepsia and irritable bowel syndrome. Individuals with a body mass index (BMI) below or higher than normal weight were more likely to have heartburn. Heartburn caused by food or beverages was reported very often by 20.0% of subjects. CONCLUSION: Heartburn is a common and chronic condition. Subjects with a BMI below or higher than normal weight are more likely to experience heartburn. Heartburn has a great impact on daily activities, sleep and quality of life. PMID:21350713

Natural history of heartburn: a 10-year population-based study.

PubMed

Olafsdottir, Linda Bjork; Gudjonsson, Hallgrimur; Jonsdottir, Heidur Hrund; Thjodleifsson, Bjarni

2011-02-07

To study the natural history and prevalence of heartburn at a 10-year interval, and to study the effect of heartburn on various symptoms and activities. A population-based postal study was carried out. Questionnaires were mailed to the same age- and gender-stratified random sample of the Icelandic population (aged 18-75 years) in 1996 and again in 2006. Subjects were classified with heartburn if they reported heartburn in the preceding year and/or week, based on the definition of heartburn. Heartburn in the preceding year was reported in 42.8% (1996) and 44.2% (2006) of subjects, with a strong relationship between those who experienced heartburn in both years. Heartburn in the preceding week was diagnosed in 20.8%. There was a significant relationship between heartburn, dyspepsia and irritable bowel syndrome. Individuals with a body mass index (BMI) below or higher than normal weight were more likely to have heartburn. Heartburn caused by food or beverages was reported very often by 20.0% of subjects. Heartburn is a common and chronic condition. Subjects with a BMI below or higher than normal weight are more likely to experience heartburn. Heartburn has a great impact on daily activities, sleep and quality of life.

Visual acuity and refractive errors in a suburban Danish population: Inter99 Eye Study.

PubMed

Kessel, Line; Hougaard, Jesper Leth; Mortensen, Claus; Jørgensen, Torben; Lund-Andersen, Henrik; Larsen, Michael

2004-02-01

The present study was performed as part of an epidemiological study, the Inter99 Eye Study. The aim of the study was to describe refractive errors and visual acuity (VA) in a suburban Danish population. The Inter99 Eye Study comprised 970 subjects aged 30-60 years and included a random control group as well as groups at high risk for ischaemic heart disease and diabetes mellitus. The present study presents VAs and refractive data from the control group (n = 502). All subjects completed a detailed questionnaire and underwent a standardized general physical and ophthalmic examination including determination of best corrected VA and subjective refractioning. Visual acuity population but in 56.8% of subjects with a university degree. Strabismic amblyopia was a significant cause of unilateral visual impairment. Myopia was approximately twice as frequent in subjects with a university degree as in the remaining study population.

Utilizing population variation, vaccination, and systems biology to study human immunology

PubMed Central

Tsang, John S.

2016-01-01

The move toward precision medicine has highlighted the importance of understanding biological variability within and across individuals in the human population. In particular, given the prevalent involvement of the immune system in diverse pathologies, an important question is how much and what information about the state of the immune system is required to enable accurate prediction of future health and response to medical interventions. Towards addressing this question, recent studies using vaccination as a model perturbation and systems-biology approaches are beginning to provide a glimpse of how natural population variation together with multiplexed, high-throughput measurement and computational analysis can be used to uncover predictors of immune response quality in humans. Here I discuss recent developments in this emerging field, with emphasis on baseline correlates of vaccination responses, sources of immune-state variability, as well as relevant features of study design, data generation, and computational analysis. PMID:26187853

Genotyping faecal samples of Bengal tiger Panthera tigris tigris for population estimation: a pilot study.

PubMed

Bhagavatula, Jyotsna; Singh, Lalji

2006-10-17

Bengal tiger Panthera tigris tigris the National Animal of India, is an endangered species. Estimating populations for such species is the main objective for designing conservation measures and for evaluating those that are already in place. Due to the tiger's cryptic and secretive behaviour, it is not possible to enumerate and monitor its populations through direct observations; instead indirect methods have always been used for studying tigers in the wild. DNA methods based on non-invasive sampling have not been attempted so far for tiger population studies in India. We describe here a pilot study using DNA extracted from faecal samples of tigers for the purpose of population estimation. In this study, PCR primers were developed based on tiger-specific variations in the mitochondrial cytochrome b for reliably identifying tiger faecal samples from those of sympatric carnivores. Microsatellite markers were developed for the identification of individual tigers with a sibling Probability of Identity of 0.005 that can distinguish even closely related individuals with 99.9% certainty. The effectiveness of using field-collected tiger faecal samples for DNA analysis was evaluated by sampling, identification and subsequently genotyping samples from two protected areas in southern India. Our results demonstrate the feasibility of using tiger faecal matter as a potential source of DNA for population estimation of tigers in protected areas in India in addition to the methods currently in use.

Evidence for Association of the E23K Variant of KCNJ11 Gene with Type 2 Diabetes in Tunisian Population: Population-Based Study and Meta-Analysis

PubMed Central

Lasram, Khaled; Ben Halim, Nizar; Hsouna, Sana; Kefi, Rym; Arfa, Imen; Ghazouani, Welid; Jamoussi, Henda; Benrahma, Houda; Kharrat, Najla; Rebai, Ahmed; Ben Ammar, Slim; Bahri, Sonia; Barakat, Abdelhamid; Abid, Abdelmajid; Abdelhak, Sonia

2014-01-01

Aims. Genetic association studies have reported the E23K variant of KCNJ11 gene to be associated with Type 2 diabetes. In Arab populations, only four studies have investigated the role of this variant. We aimed to replicate and validate the association between the E23K variant and Type 2 diabetes in Tunisian and Arab populations. Methods. We have performed a case-control association study including 250 Tunisian patients with Type 2 diabetes and 267 controls. Allelic association has also been evaluated by 2 meta-analyses including all population-based studies among Tunisians and Arabs (2 and 5 populations, resp.). Results. A significant association between the E23K variant and Type 2 diabetes was found (OR = 1.6, 95% CI = 1.14–2.27, and P = 0.007). Furthermore, our meta-analysis has confirmed the significant role of the E23K variant in susceptibility of Type 2 diabetes in Tunisian and Arab populations (OR = 1.29, 95% CI = 1.15–1.46, and P < 10−3 and OR = 1.33, 95% CI = 1.13–1.56, and P = 0.001, resp.). Conclusion. Both case-control and meta-analyses results revealed the significant association between the E23K variant of KCNJ11 and Type 2 diabetes among Tunisians and Arabs. PMID:25165692

The population ecology of infectious diseases: pertussis in Thailand as a case study.

PubMed

Blackwood, J C; Cummings, D A T; Broutin, H; Iamsirithaworn, S; Rohani, P

2012-12-01

Many of the fundamental concepts in studying infectious diseases are rooted in population ecology. We describe the importance of population ecology in exploring central issues in infectious disease research including identifying the drivers and dynamics of host-pathogen interactions and pathogen persistence, and evaluating the success of public health policies. The use of ecological concepts in infectious disease research is demonstrated with simple theoretical examples in addition to an analysis of case notification data of pertussis, a childhood respiratory disease, in Thailand as a case study. We stress that further integration of these fields will have significant impacts in infectious diseases research.

Etiology and management of esophageal food impaction: a population based study.

PubMed

Gretarsdottir, Helga M; Jonasson, Jon Gunnlaugur; Björnsson, Einar S

2015-05-01

Esophageal food impaction (FI) is a common clinical problem with limited information on incidence. Previous population based studies are lacking. The incidence, main etiological factors, recurrence and outcome of FI was determined in the present study in a population based setting. This was a study of consecutive adult patients who presented with FI from 2008 to 2013 at the National University Hospital of Iceland. The mean crude incidence rate of FI was calculated. Retrospective analysis was undertaken on relevant clinical data such as type of bolus, management, complications, recurrence rate, risk factors for recurrence, and outcome. Overall 308 patients had endoscopically confirmed FI, males 199/308 (65%), median age 62 years. The mean crude incidence was 25 per 100,000 inhabitants per year. The types of FI was meat (68%), fish (12%), vegetable (4%) and other food/objects (16%). Causes for the FI included: esophageal strictures (45%), hiatal hernia (22%), eosinophilic esophagitis (EoE) (16%) and esophageal carcinoma (2%). Recurrence appeared in 21%, in which 24/48 (50%) had EoE vs. 40/260 (15%) in others (p = 0.0001). The removal of the foreign body was successful in 98% of the cases during the first endoscopy. Endoscopic associated complications included four (1.3%) aspirations, one (0.3%) esophageal perforation and one Boerhaave syndrome at presentation (both had EoE). The incidence of FI is the highest reported to date. EoE was strongly associated with recurrence of FI. In a population based setting endoscopy is a safe and effective procedure for removing FI.

A 1000 Arab genome project to study the Emirati population.

PubMed

Al-Ali, Mariam; Osman, Wael; Tay, Guan K; AlSafar, Habiba S

2018-04-01

Discoveries from the human genome, HapMap, and 1000 genome projects have collectively contributed toward the creation of a catalog of human genetic variations that has improved our understanding of human diversity. Despite the collegial nature of many of these genome study consortiums, which has led to the cataloging of genetic variations of different ethnic groups from around the world, genome data on the Arab population remains overwhelmingly underrepresented. The National Arab Genome project in the United Arab Emirates (UAE) aims to address this deficiency by using Next Generation Sequencing (NGS) technology to provide data to improve our understanding of the Arab genome and catalog variants that are unique to the Arab population of the UAE. The project was conceived to shed light on the similarities and differences between the Arab genome and those of the other ethnic groups.

The Relationship between General Population Suicide Rates and the Internet: A Cross-National Study

ERIC Educational Resources Information Center

Shah, Ajit

2010-01-01

Internet Web sites and chat rooms have been reported both to promote suicides and have a positive beneficial effect on suicidal individuals. There is a paucity of studies examining the role of the Internet in general population suicide rates. The relationship between general population suicide rates and the prevalence of Internet users was…

Relationship Status among Parents of Children with Autism Spectrum Disorders: A Population-Based Study

ERIC Educational Resources Information Center

Freedman, Brian H.; Kalb, Luther G.; Zablotsky, Benjamin; Stuart, Elizabeth A.

2012-01-01

Despite speculation about an 80% divorce rate among parents of children with an Autism Spectrum Disorder (ASD), very little empirical and no epidemiological research has addressed the issue of separation and divorce among this population. Data for this study was taken from the 2007 National Survey of Children's Health, a population-based,…

Ethical issues in using Twitter for population-level depression monitoring: a qualitative study.

PubMed

Mikal, Jude; Hurst, Samantha; Conway, Mike

2016-04-14

Recently, significant research effort has focused on using Twitter (and other social media) to investigate mental health at the population-level. While there has been influential work in developing ethical guidelines for Internet discussion forum-based research in public health, there is currently limited work focused on addressing ethical problems in Twitter-based public health research, and less still that considers these issues from users' own perspectives. In this work, we aim to investigate public attitudes towards utilizing public domain Twitter data for population-level mental health monitoring using a qualitative methodology. The study explores user perspectives in a series of five, 2-h focus group interviews. Following a semi-structured protocol, 26 Twitter users with and without a diagnosed history of depression discussed general Twitter use, along with privacy expectations, and ethical issues in using social media for health monitoring, with a particular focus on mental health monitoring. Transcripts were then transcribed, redacted, and coded using a constant comparative approach. While participants expressed a wide range of opinions, there was an overall trend towards a relatively positive view of using public domain Twitter data as a resource for population level mental health monitoring, provided that results are appropriately aggregated. Results are divided into five sections: (1) a profile of respondents' Twitter use patterns and use variability; (2) users' privacy expectations, including expectations regarding data reach and permanence; (3) attitudes towards social media based population-level health monitoring in general, and attitudes towards mental health monitoring in particular; (4) attitudes towards individual versus population-level health monitoring; and (5) users' own recommendations for the appropriate regulation of population-level mental health monitoring. Focus group data reveal a wide range of attitudes towards the use of public

A Study of Upper Error Limits in Accounting Populations.

DTIC Science & Technology

1986-09-01

The error amount intensity is a population characteristic obtained by dividing the total...423.36/$763,931.19). This population characteristic is of interest because the results of the simulation done for research questions four through v.o

A rapid screening of ancestry for genetic association studies in an admixed population from Pernambuco, Brazil.

PubMed

Coelho, A V C; Moura, R R; Cavalcanti, C A J; Guimarães, R L; Sandrin-Garcia, P; Crovella, S; Brandão, L A C

2015-03-31

Genetic association studies determine how genes influence traits. However, non-detected population substructure may bias the analysis, resulting in spurious results. One method to detect substructure is to genotype ancestry informative markers (AIMs) besides the candidate variants, quantifying how much ancestral populations contribute to the samples' genetic background. The present study aimed to use a minimum quantity of markers, while retaining full potential to estimate ancestries. We tested the feasibility of a subset of the 12 most informative markers from a previously established study to estimate influence from three ancestral populations: European, African and Amerindian. The results showed that in a sample with a diverse ethnicity (N = 822) derived from 1000 Genomes database, the 12 AIMs had the same capacity to estimate ancestries when compared to the original set of 128 AIMs, since estimates from the two panels were closely correlated. Thus, these 12 SNPs were used to estimate ancestry in a new sample (N = 192) from an admixed population in Recife, Northeast Brazil. The ancestry estimates from Recife subjects were in accordance with previous studies, showing that Northeastern Brazilian populations show great influence from European ancestry (59.7%), followed by African (23.0%) and Amerindian (17.3%) ancestries. Ethnicity self-classification according to skin-color was confirmed to be a poor indicator of population substructure in Brazilians, since ancestry estimates overlapped between classifications. Thus, our streamlined panel of 12 markers may substitute panels with more markers, while retaining the capacity to control for population substructure and admixture, thereby reducing sample processing time.

Which population groups should be targeted for cardiovascular prevention? A modelling study based on the Norwegian Hordaland Health Study (HUSK).

PubMed

Brekke, Mette; Rekdal, Magne; Straand, Jørund

2007-06-01

To assess level of cardiovascular risk factors in a non-selected, middle-aged population. To estimate the proportion target for risk intervention according to present guidelines and according to different cut-off levels for two risk algorithms. Population survey, modelling study. The Norwegian Hordaland Health Study (HUSK) 1997-99. A total of 22 289 persons born in 1950-57. Own and relatives' cardiovascular morbidity, antihypertensive and lipid-lowering treatment, smoking, blood pressure, cholesterol. Framingham and Systematic Coronary Risk Evaluation (SCORE) algorithms. The European guidelines on CVD prevention in clinical practice were applied to estimate size of risk groups. Some 9.7% of men and 7.6% of women had CVD, diabetes mellitus, a high level of one specific risk factor, or received lipid-lowering or antihypertensive treatment. Applying a SCORE (60 years) cut-off level at 5% to the rest of the population selected 52.4% of men and 0.8% of women into a primary prevention group, while a cut-off level at 8% included 22.0% and 0.06% respectively. A cut-off level for the Framingham score (60 years) of 20% selected 43.6% of men and 4.7% of women, while a cut-off level of 25% selected 25.6% of men and 1.8% of women. The findings illustrate how choices regarding risk estimation highly affect the size of the target population. Modelling studies are important when preparing guidelines, to address implications for resource allocation and risk of medicalization. The population share to be targeted for primary prevention ought to be estimated, including the impact of various cut-off points for risk algorithms on the size of the risk population.

Oceanic heterotrophic dinoflagellates: distribution, abundance, and role as microzooplankton

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

Lessard, E.J.

1984-01-01

The primary objectives of this thesis were to determine the distribution and abundance of heterotrophic dinoflagellates across the Gulf Stream system off Cape Hatteras and to assess the potential grazing impact of these microheterotrophs in plankton communities. A list of species encountered in this study and their trophic status based on epifluorescence is presented, as well as observations on the presence of external or internal symbionts. The abundance of heterotrophic dinoflagellates across the Gulf Stream region off Cape Hatteras was determined from bimonthly net tow samples over a year and from whole water samples in March. Their average abundance wasmore » twice that of net ciliates in the net plankton and ten times that of ciliates in the nanoplankton. An isotope technique was developed to measure grazing rates of individual dinoflaggellates and other microzooplankton which cannot be separated in natural populations on the basis of size. /sup 3/H-thymidine and /sup 14/C-bicarbonate were used to label natural heterotrophic (bacteria and bacterivores) and autotrophic (phytoplankton and herbivores) food, respectively. Estimates of the grazing impact of heterotrophic kinoflagellates relative to other groups of heterotrophs on phytoplankton and bacteria were made by combining abundance data and clearance rates. Such calculations suggested that heterotrophic dinoflagellates may be an important group of grazers in oceanic waters.« less

Metabolomics applied to diabetes-lessons from human population studies.

PubMed

Liggi, Sonia; Griffin, Julian L

2017-12-01

The 'classical' distribution of type 2 diabetes (T2D) across the globe is rapidly changing and it is no longer predominantly a disease of middle-aged/elderly adults of western countries, but it is becoming more common through Asia and the Middle East, as well as increasingly found in younger individuals. This global altered incidence of T2D is most likely associated with the spread of western diets and sedentary lifestyles, although there is still much debate as to whether the increased incidence rates are due to an overconsumption of fats, sugars or more generally high-calorie foods. In this context, understanding the interactions between genes of risk and diet and how they influence the incidence of T2D will help define the causative pathways of the disease. This review focuses on the use of metabolomics in large cohort studies to follow the incidence of type 2 diabetes in different populations. Such approaches have been used to identify new biomarkers of pre-diabetes, such as branch chain amino acids, and associate metabolomic profiles with genes of known risk in T2D from large scale GWAS studies. As the field develops, there are also examples of meta-analysis across metabolomics cohort studies and cross-comparisons with different populations to allow us to understand how genes and diet contribute to disease risk. Such approaches demonstrate that insulin resistance and T2D have far reaching metabolic effects beyond raised blood glucose and how the disease impacts systemic metabolism. Copyright © 2017 Elsevier Ltd. All rights reserved.

Population Stratification in the Candidate Gene Study: Fatal Threat or Red Herring?

ERIC Educational Resources Information Center

Hutchison, Kent E.; Stallings, Michael; McGeary, John; Bryan, Angela

2004-01-01

Advances in molecular genetics have provided behavioral scientists with a means of investigating the influence of genetic factors on human behavior. Unfortunately, recent candidate gene studies have produced inconsistent results, and a frequent scapegoat for the lack of replication across studies is the threat of population stratification. This…

A model study of assisted adiabatic transfer of population in the presence of collisional dephasing

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

Masuda, Shumpei, E-mail: shumpei.masuda@aalto.fi; Rice, Stuart A., E-mail: s-rice@uchicago.edu

2015-06-28

Previous studies have demonstrated that when experimental conditions generate non-adiabatic dynamics that prevents highly efficient population transfer between states of an isolated system by stimulated Raman adiabatic passage (STIRAP), the addition of an auxiliary counter-diabatic field (CDF) can restore most or all of that efficiency. This paper examines whether that strategy is also successful in a non-isolated system in which the energies of the states fluctuate, e.g., when a solute is subject to collisions with solvent. We study population transfer in two model systems: (i) the three-state system used by Demirplak and Rice [J. Chem. Phys. 116, 8028 (2002)] andmore » (ii) a four-state system, derived from the simulation studies of Demirplak and Rice [J. Chem. Phys. 125, 194517 (2006)], that mimics HCl in liquid Ar. Simulation studies of the vibrational manifold of HCl in dense fluid Ar show that the collision induced vibrational energy level fluctuations have asymmetric distributions. Representations of these asymmetric energy level fluctuation distributions are used in both models (i) and (ii). We identify three sources of degradation of the efficiency of STIRAP generated selective population transfer in model (ii): too small pulse areas of the laser fields, unwanted interference arising from use of strong fields, and the vibrational detuning. For both models (i) and (ii), our examination of the efficiency of STIRAP + CDF population transfer under the influence of the asymmetric distribution of the vibrational energy fluctuations shows that there is a range of field strengths and pulse durations under which STIRAP + CDF control of population transfer has greater efficiency than does STIRAP generated population transfer.« less

Seroprevalence of Helicobacter pylori in Hispanics living in Puerto Rico: A population-based study.

PubMed

González-Pons, María; Soto-Salgado, Marievelisse; Sevilla, Javier; Márquez-Lespier, Juan M; Morgan, Douglas; Pérez, Cynthia M; Cruz-Correa, Marcia

2018-02-01

Helicobacter pylori is an important etiologic factor for peptic ulcers and gastric cancer, one of the top ten leading causes of cancer death in Puerto Rico. However, the prevalence of H. pylori infections in this population was previously unknown. The aim of this study was to examine the seroprevalence of H. pylori and its associated risk factors in Puerto Rico. A cross-sectional study was designed using an existing population-based biorepository. Seropositivity was determined using the Premier ™ H. pylori immunoassay. Helicobacter pylori seroprevalence was estimated with 95% confidence using marginal standardization following logistic regression. To assess the risk factors associated with H. pylori seropositivity, a multivariable log-binomial model was fitted to estimate the prevalence ratio (PR) and its 95% confidence interval (95% CI). A total of 528 population-based serum samples were analyzed. The mean age of the study population was 41 ± 12 years, of whom 55.3% were females. The overall seroprevalence of H. pylori was 33.0% (95% CI = 28.3%-38.1%). Increasing age and having <12 years of education were significantly (P < .05) associated with H. pylori seropositivity in the multivariable model; however, residing in counties with low population density reached marginal significance (P = .085). We report that H. pylori infection is common among Hispanics living in Puerto Rico. The H. pylori seroprevalence observed in Puerto Rico is similar to the seroprevalence reported in the overall population of the United States. The association between H. pylori seroprevalence and the risk factors analyzed offers insight into the epidemiology of gastric cancer in Puerto Rico and warrants further investigation. © 2017 The Authors. Helicobacter Published by John Wiley & Sons Ltd.

Human and animal studies: portals into the whole body and whole population response

EPA Science Inventory

Human and animal studies: portals into the whole body and whole population response Michael C. Madden1 and Brett Winters21US Environmental Protection Agency and 2University of North Carolina Human Studies Facility, Chapel Hill, North Carolina, USA Studies involving collection and...

Simulating a base population in honey bee for molecular genetic studies

PubMed Central

2012-01-01

Background Over the past years, reports have indicated that honey bee populations are declining and that infestation by an ecto-parasitic mite (Varroa destructor) is one of the main causes. Selective breeding of resistant bees can help to prevent losses due to the parasite, but it requires that a robust breeding program and genetic evaluation are implemented. Genomic selection has emerged as an important tool in animal breeding programs and simulation studies have shown that it yields more accurate breeding value estimates, higher genetic gain and low rates of inbreeding. Since genomic selection relies on marker data, simulations conducted on a genomic dataset are a pre-requisite before selection can be implemented. Although genomic datasets have been simulated in other species undergoing genetic evaluation, simulation of a genomic dataset specific to the honey bee is required since this species has a distinct genetic and reproductive biology. Our software program was aimed at constructing a base population by simulating a random mating honey bee population. A forward-time population simulation approach was applied since it allows modeling of genetic characteristics and reproductive behavior specific to the honey bee. Results Our software program yielded a genomic dataset for a base population in linkage disequilibrium. In addition, information was obtained on (1) the position of markers on each chromosome, (2) allele frequency, (3) χ2 statistics for Hardy-Weinberg equilibrium, (4) a sorted list of markers with a minor allele frequency less than or equal to the input value, (5) average r2 values of linkage disequilibrium between all simulated marker loci pair for all generations and (6) average r2 value of linkage disequilibrium in the last generation for selected markers with the highest minor allele frequency. Conclusion We developed a software program that takes into account the genetic and reproductive biology specific to the honey bee and that can be used to

Analysis of gingival biopsies in the Gujarati population: a retrospective study.

PubMed

Manjunatha, Bhari Sharanesha; Sutariya, Rakesh; Nagamahita, V; Dholia, Bhavik; Shah, Vandana

2014-01-01

Biopsy is an important diagnostic tool used in the diagnosis of lesions ranging from simple non-neoplastic, tumor-like lesions to malignancies, and is often the only way to diagnose oral lesions and diseases. The gingiva is the most common site for some kind of irritation or low-grade injury, resulting in localized overgrowths that are considered to be reactive and non-neoplastic lesions. This aim of this study is to analyze the frequency and distribution of gingival lesions in the Gujarati population. In this retrospective study, gingival biopsies submitted for a period of five years were included. Microscopic slides of all the cases were reviewed by two observers for confirmation of the diagnosis. Among the 106 cases of gingival biopsies, the most frequent category of lesions encountered was the non-neoplastic category, which accounted for 73.58% of the cases. Both benign and malignant neoplasms constituted 26.42% of the cases. Among the non-neoplastic lesions, Pyogenic granuloma was the most frequent lesion (38.46%), followed by fibrous hyperplasia (20.51%), inflammatory hyperplasia (19.23%), and Epulis (8.97%). Neoplasms accounted for 26.42% of the gingival biopsies (92.85% benign and 7.15% malignant). Among the benign neoplastic lesions, Fibroma (30.76%) and Fibrolipoma (26.92%) were the most frequent, followed by peripheral ossifying fibroma (23.08%) and peripheral giant cell granuloma (11%). It is difficult to compare studies carried out in various countries due to differences in people's attitudes toward oral health and the accessibility of various population groups to biopsy services. Nevertheless, this study has provided some information about the frequency and distribution of biopsied gingival lesions in the Gujarati population over a period of five years.

Population.

ERIC Educational Resources Information Center

International Planned Parenthood Federation, London (England).

In an effort to help meet the growing interest and concern about the problems created by the rapid growth of population, The International Planned Parenthood Federation has prepared this booklet with the aim of assisting the study of the history and future trends of population growth and its impact on individual and family welfare, national,…

Clinical Characteristics and Outcome of Hepatic Sarcoidosis: A Population-Based Study 1976-2013.

PubMed

Ungprasert, Patompong; Crowson, Cynthia S; Simonetto, Douglas A; Matteson, Eric L

2017-10-01

Data on clinical manifestations and outcome of hepatic sarcoidosis are scarce. This study aimed to use a population-based cohort of patients with incident sarcoidosis to better describe the characteristics of hepatic sarcoidosis. A cohort of incident cases of sarcoidosis in Olmsted County, MN, USA, from 1976 to 2013 was identified from the database. Diagnosis was verified by individual medical record review. Confirmed cases of sarcoidosis were then reviewed for liver involvement. Data on clinical manifestations, imaging study, liver biochemical tests, treatment, and outcome were collected. Cumulative incidence of cirrhosis adjusted for the competing risk of death was estimated. A total of 345 cases of incident sarcoidosis were identified. Of these, 19 cases (6%) had liver involvement (mean age 46.1 years, 53% female and 79% Caucasian). Most patients had asymptomatic liver disease and were discovered in pursuit of abnormal biochemical tests and imaging studies. Alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT) were elevated in the majority of patients (88 and 90%, respectively). Elevated transaminases were less common and less severe. About half of patients had abnormal imaging study with hypodense nodular lesions being the most common abnormality (six patients) followed by hepatomegaly (three patients). Liver biopsy revealed non-caseating granuloma in 88% (14 of 16 patients). A total of four patients developed cirrhosis. Involvement of the liver by sarcoidosis was seen in 6% of patients with sarcoidosis. The majority of patients were asymptomatic. Elevated ALP and GGT were the most common abnormal biochemical tests. Liver biopsy revealed non-caseating granuloma in almost all cases. Cirrhosis was seen in a significant number of patients. Generalizability of the observations to other populations may be limited, as the studied population was predominantly Caucasian. The prevalence of liver disease may be higher in more diverse populations.

Prevalence of diabetes mellitus and prediabetes in the adult Romanian population: PREDATORR study.

PubMed

Mota, Maria; Popa, Simona Georgiana; Mota, Eugen; Mitrea, Adina; Catrinoiu, Doina; Cheta, Dan Mircea; Guja, Cristian; Hancu, Nicolae; Ionescu-Tirgoviste, Constantin; Lichiardopol, Radu; Mihai, Bogdan Mircea; Popa, Amorin Remus; Zetu, Cornelia; Bala, Cornelia Gabriela; Roman, Gabriela; Serafinceanu, Cristian; Serban, Viorel; Timar, Romulus; Veresiu, Ioan Andrei; Vlad, Adrian Radu

2016-05-01

The PREDATORR (PREvalence of DiAbeTes mellitus, prediabetes, overweight, Obesity, dyslipidemia, hyperuricemia and chronic kidney disease in Romania) study is the first national study analyzing the prevalence of diabetes mellitus (DM) and prediabetes, and their association with cardiometabolic, sociodemographic, and lifestyle risk factors in the Romanian population aged 20-79 years. This was an epidemiological study with a stratified, cross-sectional, cluster random sampling design. Sociodemographic, lifestyle, and anamnestic data were collected through self- and interviewer-administered questionnaires, and biochemical assays and oral glucose tolerance tests were performed. In all, 2728 participants from 101 clinics of general practitioners were randomly selected, with a probability proportional to population size according to the 2002 Romanian Census. The participation rate was 99.6%. Impaired glucose regulation (prediabetes, known and unknown DM) was found in 28.1% of the study population. The overall age- and sex-adjusted prevalence of DM was 11.6% (95% CI 9.6%-13.6%), of which 2.4% (95% CI 1.7%-3.1%) had unknown DM. The prevalence of DM increased with age and was higher in men than in women. The age- and sex-adjusted prevalence of prediabetes was 16.5% (95%CI 14.8%-18.2%), with the highest percentage in the 60-79 year age group and in women. Obesity, abdominal obesity, dyslipidemia, low education level, and a family history of diabetes were associated with glucose metabolism disorders. The PREDATORR study shows a high prevalence of impaired glucose regulation in the adult Romanian population, providing data on the prevalence of DM and prediabetes and their association with several risk factors. © 2015 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley Sons & Australia, Ltd.

Population versus hospital controls for case-control studies on cancers in Chinese hospitals

PubMed Central

2011-01-01

Background Correct control selection is crucial to the internal validity of case-control studies. Little information exists on differences between population and hospital controls in case-control studies on cancers in Chinese hospital setting. Methods We conducted three parallel case-control studies on leukemia, breast and colorectal cancers in China between 2009 and 2010, using population and hospital controls to separately match 540 incident cases by age, gender and residency at a 1:1 ratio. Demographic and lifestyle factors were measured using a validated questionnaire in face-to-face interview. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained using conditional logistic regression analyses. Results The two control groups had closely similar exposure distributions of 15 out of 16 factors, with the only exception being that hospital controls were less likely to have a BMI ≥ 25 (OR = 0.71, 95% CI: 0.54, 0.93). For exposure of green tea drinking, the adjusted ORs (95% CIs) comparing green tealeaves intake ≥ 1000 grams annually with non-drinkers were 0.51 (0.31, 0.83) and 0.21 (0.27, 0.74) for three cancers combined, 0.06 (0.01, 0.61) and 0.07 (0.01, 0.47) for breast cancer, 0.52 (0.29, 0.94) and 0.45 (0.25, 0.82) for colorectal cancer, 0.65 (0.08, 5.63) and 0.57 (0.07, 4.79) for leukemia using hospital and population controls respectively. Conclusions The study found that hospital controls were comparable with population controls for most demographic characteristics and lifestyle factors measured, but there was a slight difference between the two control groups. Hospital outpatients provide a satisfactory control group in hospital-based case-control study in the Chinese hospital setting. PMID:22171783

Population versus hospital controls for case-control studies on cancers in Chinese hospitals.

PubMed

Li, Lin; Zhang, Min; Holman, D'Arcy

2011-12-15

Correct control selection is crucial to the internal validity of case-control studies. Little information exists on differences between population and hospital controls in case-control studies on cancers in Chinese hospital setting. We conducted three parallel case-control studies on leukemia, breast and colorectal cancers in China between 2009 and 2010, using population and hospital controls to separately match 540 incident cases by age, gender and residency at a 1:1 ratio. Demographic and lifestyle factors were measured using a validated questionnaire in face-to-face interview. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained using conditional logistic regression analyses. The two control groups had closely similar exposure distributions of 15 out of 16 factors, with the only exception being that hospital controls were less likely to have a BMI ≥ 25 (OR = 0.71, 95% CI: 0.54, 0.93). For exposure of green tea drinking, the adjusted ORs (95% CIs) comparing green tealeaves intake ≥ 1000 grams annually with non-drinkers were 0.51 (0.31, 0.83) and 0.21 (0.27, 0.74) for three cancers combined, 0.06 (0.01, 0.61) and 0.07 (0.01, 0.47) for breast cancer, 0.52 (0.29, 0.94) and 0.45 (0.25, 0.82) for colorectal cancer, 0.65 (0.08, 5.63) and 0.57 (0.07, 4.79) for leukemia using hospital and population controls respectively. The study found that hospital controls were comparable with population controls for most demographic characteristics and lifestyle factors measured, but there was a slight difference between the two control groups. Hospital outpatients provide a satisfactory control group in hospital-based case-control study in the Chinese hospital setting.

Surnames in Chile: a study of the population of Chile through isonymy.

PubMed

Barrai, I; Rodriguez-Larralde, A; Dipierri, J; Alfaro, E; Acevedo, N; Mamolini, E; Sandri, M; Carrieri, A; Scapoli, C

2012-03-01

In Chile, the Hispanic dual surname system is used. To describe the isonymic structure of this country, the distribution of 16,277,255 surnames of 8,178,209 persons was studied in the 15 regions, the 54 provinces, and the 346 communes of the nation. The number of different surnames found was 72,667. Effective surname number (Fisher's α) for the entire country was 309.0, the average for regions was 240.8 ± 17.6, for provinces 209.2 ± 8.9, and for communes 178.7 ± 4.7. These values display a variation of inbreeding between administrative levels in the Chilean population, which can be attributed to the 'Prefecture effect' of Nei and Imaizumi. Matrices of isonymic distances between units within administrative levels were tested for correlation with geographic distance. The correlations were highest for provinces (r = 0.630 ± 0.019 for Euclidean distance) and lowest for communes (r = 0.366 ± 0.009 for Lasker's). The geographical distribution of the first three-dimensions of the Euclidean distance matrix suggests that population diffusion may have taken place from the north of the country toward the center and south. The prevalence of European plus European-Amerindian (95.4%) over Amerindian ethnicity (4.6%, CIA World Factbook) is compatible with diffusion of Caucasian groups over a low-density area populated by indigenous groups. The significant excess of maternal over paternal indigenous surnames indicates some asymmetric mating between nonAmerindian and Amerindian Chileans. The available studies of Y-markers and mt-markers are in agreement with this asymmetry. In the present work, we investigate the Chilean population with the aim of detecting its structure through the study of isonymy (Crow and Mange,1965) in the three administrative levels of the nation, namely 15 regions, 54 provinces, and 346 communes. Copyright © 2012 Wiley Periodicals, Inc.

Dietary patterns and colorectal cancer: results from a Canadian population-based study.

PubMed

Chen, Zhi; Wang, Peizhong Peter; Woodrow, Jennifer; Zhu, Yun; Roebothan, Barbara; Mclaughlin, John R; Parfrey, Patrick S

2015-01-15

The relationship between major dietary patterns and colorectal cancer (CRC) in other populations largely remains consistent across studies. The objective of the present study is to assess if dietary patterns are associated with the risk of CRC in the population of Newfoundland and Labrador (NL). Data from a population based case-control study in the province of NL were analyzed, including 506 CRC patients (306 men and 200 women) and 673 controls (400 men and 273 women), aged 20-74 years. Dietary habits were assessed by a 169-item food frequency questionnaire (FFQ). Logistic regression analyses were performed to investigate the association between dietary patterns and the CRC risk. Three major dietary patterns were derived using factor analysis, namely a Meat-diet pattern, a Plant-based diet pattern and a Sugary-diet pattern. In combination the three dietary patterns explained 74% of the total variance in food intake. Results suggest that the Meat-diet and the Sugary-diet increased the risk of CRC with corresponding odds ratios (ORs) of 1.84 (95% CI: 1.19-2.86) and 2.26 (95% CI: 1.39-3.66) for people in the highest intake quintile compared to those in the lowest. Whereas plant-based diet pattern decreases the risk of CRC with a corresponding OR of 0.55 (95% CI: 0.35-0.87). Even though odds ratios (ORs) were not always statistically significant, largely similar associations across three cancer sites were found: the proximal colon, the distal colon, and the rectum. The finding that Meat-diet/Sugary-diet patterns increased and Plant-based diet pattern decreased the risk of CRC would guide the promotion of healthy eating for primary prevention of CRC in this population.

Histological study of some Echium vulgare, Pulmonaria officinalis and Symphytum officinale populations.

PubMed

Papp, Nóra; Bencsik, Tímea; Németh, Kitti; Gyergyák, Kinga; Sulc, Alexandra; Farkas, Agnes

2011-10-01

Plants living in different ecological habitats can show significant variability in their histological and phytochemical characters. The main histological features of various populations of three medicinal plants from the Boraginaceae family were studied. Stems, petioles and leaves were investigated by light microscopy in vertical and transverse sections. The outline of the epidermal cells, as well as the shape and cell number of trichomes was studied in leaf surface casts. Differences were measured among the populations of Echium vulgare in the width and height of epidermis cells in the stem, petiole and leaf, as well as in the size of palisade cells in the leaves. Among the populations of Pulmonaria officinalis significant differences were found in the length of trichomes and in the slightly or strongly wavy outline of epidermal radial cell walls. Populations of Symphytum officinale showed variance in the height of epidermal cells in leaves and stems, length of palisade cells and number of intercellular spaces in leaves, and the size of the central cavity in the stem. Boraginaceae bristles were found to be longer in plants in windy/shady habitats as opposed to sunny habitats, both in the leaves and stems ofP. officinalis and S. officinale, which might be connected to varying levels of exposure to wind. Longer epidermal cells were detected in the leaves and stems of both E. vulgare and S. officinale plants living in shady habitats, compared with shorter cells in sunny habitats. Leaf mesophyll cells were shorter in shady habitats as opposed to longer cells in sunny habitats, both in E. vulgare and S. officinale. This combination of histological characters may contribute to the plant's adaptation to various amounts of sunshine. The reported data prove the polymorphism of the studied taxa, as well as their ability to adapt to various ecological circumstances.

Utilizing population variation, vaccination, and systems biology to study human immunology.

PubMed

Tsang, John S

2015-08-01

The move toward precision medicine has highlighted the importance of understanding biological variability within and across individuals in the human population. In particular, given the prevalent involvement of the immune system in diverse pathologies, an important question is how much and what information about the state of the immune system is required to enable accurate prediction of future health and response to medical interventions. Towards addressing this question, recent studies using vaccination as a model perturbation and systems-biology approaches are beginning to provide a glimpse of how natural population variation together with multiplexed, high-throughput measurement and computational analysis can be used to uncover predictors of immune response quality in humans. Here I discuss recent developments in this emerging field, with emphasis on baseline correlates of vaccination responses, sources of immune-state variability, as well as relevant features of study design, data generation, and computational analysis. Copyright © 2015 The Author. Published by Elsevier Ltd.. All rights reserved.

Population studies of Glossina pallidipes in Ethiopia: emphasis on cuticular hydrocarbons and wing morphometric analysis.

PubMed

Getahun, M N; Cecchi, G; Seyoum, E

2014-10-01

Tsetse flies, like many insects, use pheromones for inter- and intra-specific communication. Several of their pheromones are cuticular hydrocarbons (CHCs) that are perceived by contact at close range. We hypothesized that for a successful implementation of the Sterile Insect Technique (SIT), along with proper identification of target area and target species, the target tsetse populations and the sterile flies must chemically communicate with each other. To study the population structuring of Glossina pallidipes in Ethiopia, CHCs were extracted and analyzed from three tsetse belts. As a comparative approach, wing morphometric analysis was performed. The analysis of the relative abundance of CHCs revealed that populations of G. pallidipes from the Rift Valley tsetse belt showed a distinct clustering compared to populations from the other two belts. The spatial pattern of CHC differences was complemented by the wing morphometric analysis. Our data suggest that CHCs of known biological and ecological role, when combined with wing morphometric data, will provide an alternative means for the study of population structuring of Glossina populations. This could aid the planning of area wide control strategies using SIT, which is dependent on sexual competence. Copyright © 2014 International Atomic Energy Agency 2014. Published by Elsevier B.V. All rights reserved.

Gestational age and school achievement: a population study.

PubMed

Searle, Amelia K; Smithers, Lisa G; Chittleborough, Catherine R; Gregory, Tess A; Lynch, John W

2017-09-01

Academic achievement varies according to gestational age but it is unclear whether achievement varies within 'term' (37-41 weeks gestation) or for 'post-term' births (≥42 weeks). We examined gestational age from preterm to post-term against a national minimum standard for academic achievement in population data. Literacy and numeracy data of 8-year-old South Australian grade 3 children in 2008-2010 were linked to routinely collected perinatal data (N=28 155). Longer gestation from 23 to 45 weeks was associated with lower risk of poor literacy and numeracy. Adjusted relative risks for being at or below national minimum standard ranged from 1.12 (95% CI 1.03 to 1.22) for 'late preterm' (32-36 weeks) for numeracy, to 1.84 (95% CI 1.48 to 2.30) for 'early preterm' (23-31 weeks) for writing. Within term, every additional week of gestational age was associated with small decreased risks of poor literacy and numeracy (eg, relative risks for poor numeracy 1.10, 95% CI 1.01 to 1.20 for 37 weeks). Population-attributable fractions for poor achievement were highest among children born 'early term' (37-39 weeks) due to their higher population prevalence. Shorter gestational age was associated with increased risk of poor literacy/numeracy. While children born 'early term' experience only between 1% and 10% increased risk, they constitute a larger proportion of children with poor educational achievement than preterm children, and thus are important to consider for supportive interventions to improve population-level achievement gains. The seemingly lower risk for post-term children showed large error estimates and warrants further consideration within even larger 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/.

A population based study comparing changes in rotavirus burden on the Island of Ireland between a highly vaccinated population and an unvaccinated population.

PubMed

Armstrong, Gillian; Gallagher, Naomh; Cabrey, Paul; Graham, Adele M; McKeown, Paul J; Jackson, Sarah; Dallat, Mary; Smithson, Richard D

2016-09-07

Rotavirus infection is a leading cause of gastroenteritis in infants and children globally. Reductions in rotavirus activity have been observed following introduction of rotavirus vaccination programmes, however a reductions have also been reported in some unvaccinated countries. The Island of Ireland incorporates the two jurisdictions Northern Ireland (NI) and the Republic of Ireland (IE). Both have similarities in climate, demography, morbidity and mortality but distinct health administrations and vaccination policies. Rotarix was added to the childhood immunisation programme in NI on the 1 July 2013. IE have not introduced routine rotavirus vaccination to date. The aim of this population based ecological study was to evaluate the impact of the rotavirus vaccine on burden of rotavirus disease in NI, and to compare with IE as an unvaccinated control population. This will help determine if the changes seen were due to the rotavirus vaccine, or due to confounding factors. A number of population based measures of disease burden were compared in both jurisdictions pre-vaccine (six years; 2007/08-2012/13) and post-vaccine (two years; 2013/14-2014/15). The data sources included national rotavirus surveillance data based on laboratory reports/notifications; hospital admission data; and notifications of gastroenteritis in under 2year olds. In the post-vaccination period, rotavirus incidence in NI dropped by 54% while in IE it increased by 19% compared to the pre-vaccine period. Notifications of gastroenteritis in under 2s in NI declined by 53% and hospital admissions in under 5year olds in NI declined by 40% in the post vaccine period. This natural experiment demonstrated a significant reduction in rotavirus disease activity post-vaccine introduction in NI with associated reductions in healthcare utilisation, with a concurrent increase in rotavirus disease activity in the non-vaccinated population in IE. These findings support rotavirus vaccination as an effective measure

Genetic causes of intellectual disability in a birth cohort: a population-based study.

PubMed

Karam, Simone M; Riegel, Mariluce; Segal, Sandra L; Félix, Têmis M; Barros, Aluísio J D; Santos, Iná S; Matijasevich, Alicia; Giugliani, Roberto; Black, Maureen

2015-06-01

Intellectual disability affects approximately 1-3% of the population and can be caused by genetic and environmental factors. Although many studies have investigated the etiology of intellectual disability in different populations, few studies have been performed in middle-income countries. The present study estimated the prevalence of genetic causes related to intellectual disability in a cohort of children from a city in south Brazil who were followed from birth. Children who showed poor performance in development and intelligence tests at the ages of 2 and 4 were included. Out of 4,231 liveborns enrolled in the cohort, 214 children fulfilled the inclusion criteria. A diagnosis was established in approximately 90% of the children evaluated. Genetic causes were determined in 31 of the children and 19 cases remained unexplained even after extensive investigation. The overall prevalence of intellectual disability in this cohort due to genetic causes was 0.82%. Because this study was nested in a cohort, there were a large number of variables related to early childhood and the likelihood of information bias was minimized by collecting information with a short recall time. This study was not influenced by selection bias, allowing identification of intellectual disability and estimation of the prevalence of genetic causes in this population, thereby increasing the possibility of providing appropriate management and/or genetic counseling. © 2015 Wiley Periodicals, Inc.

A population approach to renal replacement therapy epidemiology: lessons from the EVEREST study.

PubMed

Caskey, Fergus J; Jager, Kitty J

2014-08-01

The marked variation that exists in renal replacement therapy (RRT) epidemiology between countries and within countries requires careful systematic examination if the root causes are to be understood. While individual patient-level studies are undoubtedly important, there is a complementary role for more population-level, area-based studies--an aetiological approach. The EVEREST Study adopted such an approach, bringing RRT incidence rates, survival and modality mix together with macroeconomic factors, general population factors and renal service organizational factors for up to 46 countries. This review considers the background to EVEREST, its key results and then the main methodological lessons and their potential application to ongoing work. © The Author 2013. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

Native American gene continuity to the modern admixed population from the Colombian Andes: Implication for biomedical, population and forensic studies.

PubMed

Criollo-Rayo, Angel A; Bohórquez, Mabel; Prieto, Rodrigo; Howarth, Kimberley; Culma, Cesar; Carracedo, Angel; Tomlinson, Ian; Echeverry de Polnaco, Maria M; Carvajal Carmona, Luis G

2018-06-07

Andean populations have variable degrees of Native American and European ancestry, representing an opportunity to study admixture dynamics in the populations from Latin America (also known as Hispanics). We characterized the genetic structure of two indigenous (Nasa and Pijao) and three admixed (Ibagué, Ortega and Planadas) groups from Tolima, in the Colombian Andes. DNA samples from 348 individuals were genotyped for six mitochondrial DNA (mtDNA), seven non-recombining Y-chromosome (NRY) region and 100 autosomal ancestry informative markers. Nasa and Pijao had a predominant Native American ancestry at the autosomal (92%), maternal (97%) and paternal (70%) level. The admixed groups had a predominant Native American mtDNA ancestry (90%), a substantial frequency of European NRY haplotypes (72%) and similar autosomal contributions from Europeans (51%) and Amerindians (45%). Pijao and nearby Ortega were indistinguishable at the mtDNA and autosomal level, suggesting a genetic continuity between them. Comparisons with multiple Native American populations throughout the Americas revealed that Pijao, had close similarities with Carib-speakers from distant parts of the continent, suggesting an ancient correlation between language and genes. In summary, our study aimed to understand Hispanic patterns of migration, settlement and admixture, supporting an extensive contribution of local Amerindian women to the gene pool of admixed groups and consistent with previous reports of European-male driven admixture in Colombia. Copyright © 2018 Elsevier B.V. All rights reserved.

The association of hyperglycaemia with prevalent tuberculosis: a population-based cross-sectional study.

PubMed

Bailey, Sarah Lou; Ayles, Helen; Beyers, Nulda; Godfrey-Faussett, Peter; Muyoyeta, Monde; du Toit, Elizabeth; Yudkin, John S; Floyd, Sian

2016-12-05

Systematic reviews suggest that the incidence of diagnosed tuberculosis is two- to- three times higher in those with diabetes mellitus than in those without. Few studies have previously reported the association between diabetes or hyperglycaemia and the prevalence of active tuberculosis and none in a population-based study with microbiologically-defined tuberculosis. Most have instead concentrated on cases of diagnosed tuberculosis that present to health facilities. We had the opportunity to measure glycaemia alongside prevalent tuberculosis. A focus on prevalent tuberculosis enables estimation of the contribution of hyperglycaemia to the population prevalence of tuberculosis. A population-based cross-sectional study was conducted among adults in 24 communities from Zambia and the Western Cape (WC) province of South Africa. Prevalent tuberculosis was defined by the presence of a respiratory sample that was culture positive for M. tuberculosis. Glycaemia was measured by random blood glucose (RBG) concentration. Association with prevalent tuberculosis was explored across the whole spectrum of glycaemia. Among 27,800 Zambian and 11,367 Western Cape participants, 4,431 (15.9%) and 1,835 (16.1%) respectively had a RBG concentration ≥7.0 mmol/L, and 405 (1.5%) and 322 (2.8%) respectively had a RBG concentration ≥11.1 mmol/L. In Zambia, the prevalence of tuberculosis was 0 · 5% (142/27,395) among individuals with RBG concentration <11.1 mmol/L and also ≥11.1 mmol/L (2/405); corresponding figures for WC were 2 · 5% (272/11,045) and 4 · 0% (13/322). There was evidence for a positive linear association between hyperglycaemia and pulmonary prevalent tuberculosis. Taking a RBG cut-off 11.1 mmol/L, a combined analysis of data from Zambian and WC communities found evidence of association between hyperglycaemia and TB (adjusted odds ratio = 2 · 15, 95% CI [1 · 17-3 · 94]). The population attributable fraction of prevalent tuberculosis

Chain pooling to minimize prediction error in subset regression. [Monte Carlo studies using population models

NASA Technical Reports Server (NTRS)

Holms, A. G.

1974-01-01

Monte Carlo studies using population models intended to represent response surface applications are reported. Simulated experiments were generated by adding pseudo random normally distributed errors to population values to generate observations. Model equations were fitted to the observations and the decision procedure was used to delete terms. Comparison of values predicted by the reduced models with the true population values enabled the identification of deletion strategies that are approximately optimal for minimizing prediction errors.

Psychedelics and mental health: a population study.

PubMed

Krebs, Teri S; Johansen, Pål-Ørjan

2013-01-01

The classical serotonergic psychedelics LSD, psilocybin, mescaline are not known to cause brain damage and are regarded as non-addictive. Clinical studies do not suggest that psychedelics cause long-term mental health problems. Psychedelics have been used in the Americas for thousands of years. Over 30 million people currently living in the US have used LSD, psilocybin, or mescaline. To evaluate the association between the lifetime use of psychedelics and current mental health in the adult population. Data drawn from years 2001 to 2004 of the National Survey on Drug Use and Health consisted of 130,152 respondents, randomly selected to be representative of the adult population in the United States. Standardized screening measures for past year mental health included serious psychological distress (K6 scale), mental health treatment (inpatient, outpatient, medication, needed but did not receive), symptoms of eight psychiatric disorders (panic disorder, major depressive episode, mania, social phobia, general anxiety disorder, agoraphobia, posttraumatic stress disorder, and non-affective psychosis), and seven specific symptoms of non-affective psychosis. We calculated weighted odds ratios by multivariate logistic regression controlling for a range of sociodemographic variables, use of illicit drugs, risk taking behavior, and exposure to traumatic events. 21,967 respondents (13.4% weighted) reported lifetime psychedelic use. There were no significant associations between lifetime use of any psychedelics, lifetime use of specific psychedelics (LSD, psilocybin, mescaline, peyote), or past year use of LSD and increased rate of any of the mental health outcomes. Rather, in several cases psychedelic use was associated with lower rate of mental health problems. We did not find use of psychedelics to be an independent risk factor for mental health problems.

USE OF POPULATION STUDIES TO IDENTIFY ASSOCIATIONS BETWEEN ADVERSE HEALTH EFFECTS AND ENVIRONMENTAL EXPOSURES TO ENDOCRINE DISRUPTING HERBICIDES

EPA Science Inventory

Not only animal studies, but also population (ecologic) studies can contribute to the identification of endocrine disrupting chemicals. Population studies are fundamental in identifying public health hazards, and provide hypotheses for more targeted studies. Chlorophenoxy herb...

Prevalence of refractive errors in the European adult population: the Gutenberg Health Study (GHS).

PubMed

Wolfram, Christian; Höhn, René; Kottler, Ulrike; Wild, Philipp; Blettner, Maria; Bühren, Jens; Pfeiffer, Norbert; Mirshahi, Alireza

2014-07-01

To study the distribution of refractive errors among adults of European descent. Population-based eye study in Germany with 15010 participants aged 35-74 years. The study participants underwent a detailed ophthalmic examination according to a standardised protocol. Refractive error was determined by an automatic refraction device (Humphrey HARK 599) without cycloplegia. Definitions for the analysis were myopia <-0.5 dioptres (D), hyperopia >+0.5 D, astigmatism >0.5 cylinder D and anisometropia >1.0 D difference in the spherical equivalent between the eyes. Exclusion criterion was previous cataract or refractive surgery. 13959 subjects were eligible. Refractive errors ranged from -21.5 to +13.88 D. Myopia was present in 35.1% of this study sample, hyperopia in 31.8%, astigmatism in 32.3% and anisometropia in 13.5%. The prevalence of myopia decreased, while the prevalence of hyperopia, astigmatism and anisometropia increased with age. 3.5% of the study sample had no refractive correction for their ametropia. Refractive errors affect the majority of the population. The Gutenberg Health Study sample contains more myopes than other study cohorts in adult populations. Our findings do not support the hypothesis of a generally lower prevalence of myopia among adults in Europe as compared with East Asia.

Rapid evolution in insect pests: the importance of space and time in population genomics studies.

PubMed

Pélissié, Benjamin; Crossley, Michael S; Cohen, Zachary Paul; Schoville, Sean D

2018-04-01

Pest species in agroecosystems often exhibit patterns of rapid evolution to environmental and human-imposed selection pressures. Although the role of adaptive processes is well accepted, few insect pests have been studied in detail and most research has focused on selection at insecticide resistance candidate genes. Emerging genomic datasets provide opportunities to detect and quantify selection in insect pest populations, and address long-standing questions about mechanisms underlying rapid evolutionary change. We examine the strengths of recent studies that stratify population samples both in space (along environmental gradients and comparing ancestral vs. derived populations) and in time (using chronological sampling, museum specimens and comparative phylogenomics), resulting in critical insights on evolutionary processes, and providing new directions for studying pests in agroecosystems. Copyright © 2018 Elsevier Inc. All rights reserved.

Folsomia Candida--An Ideal Organism for Population Studies in the Laboratory

ERIC Educational Resources Information Center

Usher, M. B.; Stoneman, C. F.

1977-01-01

Folsomia candida is presented as an ideal organism for population studies that can be carried out cheaply and easily in school laboratory conditions. Means of identifying, obtaining, and culturing these organisms are described together with some indication of the kinds of investigations which can be performed. (Author/MA)

Population and population policy in Pakistan.

PubMed

Mauldin, W P

1963-02-01

Pakistan is a divided country with different religious groups represented. Since independence in 1941, the Muslim population has increased more rapidly than the Hindu population, the West Pakistan population more rapidly and steadily than the East Pakistan population. In the late 1950s the Pakistan government initiated a family planning program. The program has trained medical and paramedical personnel in family planning, added family planning services to existing medical centers, planned for a National Research Institute of Family Planning, employed mobile units to reach outlying areas, conducted limited clinical studies on some contraceptives, and used mass media advertising. Only India and Japan are doing more with government-sponsored family planning. A weak organizational structure and an inadequate number of trained personnel are the main weakness of the program. It is too early to assess the success of the program. A 10-point reduction in annual birth rates will be considered successful.

Suicide after release from prison - a population-based cohort study from Sweden

PubMed Central

Haglund, Axel; Tidemalm, Dag; Jokinen, Jussi; Långström, Niklas; Liechtenstein, Paul; Fazel, Seena; Runeson, Bo

2015-01-01

Objective Released prisoners have high suicide rates compared with the general population, but little is known about risk factors and possible causal pathways. We conducted a population-based cohort study to investigate rates and risk factors for suicide in people previously imprisoned. Methods We identified individuals released from prison in Sweden between January 1, 2005 and December 31, 2009 through linkage of national population-based registers. Released prisoners were followed from the day of release until death, emigration, new incarceration, or December 31, 2009. Survival analyses were conducted to compare incidence rates and psychiatric morbidity with non-convicted population controls matched on gender and year of birth. Results We identified 38,995 releases among 26,953 prisoners (7.6% females) during 2005-2009. Overall, 127 suicides occurred, accounting for 14% of all deaths after release (n=920). The mean suicide rate was 204 per 100,000 person years yielding an incidence rate ratio of 18.2 (95% CI 13.9-23.8) compared with general population controls. Previous substance use disorder (Hazard Ratio [HR]=2.1, 1.4-3.2), suicide attempt (HR=2.5, 1.7-3.7), and being born in Sweden vs. abroad (HR=2.1, 1.2-3.6) were independent risk factors for suicide after release. Conclusions Released prisoners are at high suicide risk and with a slightly different pattern of psychiatric risk factors for suicide compared with the general population. Results suggest appropriate allocation of resources to facilitate transition to life outside prison and increased attention to prisoners with both a previous suicide attempt and substance use disorder. PMID:25373114

Does childhood cancer affect parental divorce rates? A population-based study.

PubMed

Syse, Astri; Loge, Jon H; Lyngstad, Torkild H

2010-02-10

PURPOSE Cancer in children may profoundly affect parents' personal relationships in terms of psychological stress and an increased care burden. This could hypothetically elevate divorce rates. Few studies on divorce occurrence exist, so the effect of childhood cancers on parental divorce rates was explored. PATIENTS AND METHODS Data on the entire Norwegian married population, age 17 to 69 years, with children age 0 to 20 years in 1974 to 2001 (N = 977,928 couples) were retrieved from the Cancer Registry, the Central Population Register, the Directorate of Taxes, and population censuses. Divorce rates for 4,590 couples who were parenting a child with cancer were compared with those of otherwise similar couples by discrete-time hazard regression models. Results Cancer in a child was not associated with an increased risk of parental divorce overall. An increased divorce rate was observed with Wilms tumor (odds ratio [OR], 1.52) but not with any of the other common childhood cancers. The child's age at diagnosis, time elapsed from diagnosis, and death from cancer did not influence divorce rates significantly. Increased divorce rates were observed for couples in whom the mothers had an education greater than high school level (OR, 1.16); the risk was particularly high shortly after diagnosis, for CNS cancers and Wilms tumors, for couples with children 0 to 9 years of age at diagnosis, and after a child's death. CONCLUSION This large, registry-based study shows that cancer in children is not associated with an increased parental divorce rate, except with Wilms tumors. Couples in whom the wife is highly educated appear to face increased divorce rates after a child's cancer, and this may warrant additional study.

Mandibular canine index: A study for gender determination in Gandhinagar population

PubMed Central

Patel, Roseline Ankit; Chaudhary, Anjani Ramchandra; Dudhia, Bhavin Bipinchandra; Macwan, Zonty Sylvestor; Patel, Purv Shashank; Jani, Yesha Vijaykumar

2017-01-01

Introduction: One of the important pieces of information gathered from tooth analysis is the sex of an individual. In most human living populations, mandibular canines show the greatest dimorphism and greatest dimensional differences between males and females. In view of these facts, the aim of this study was to establish the standard mandibular canine index (MCI) and estimate the sexual dimorphism in the population of Gandhinagar district of Gujarat state. Materials and Methods: The study consisted of 400 subjects, 200 males and 200 females in the age group of 20–40 years. The mesiodistal (MD) width of the right and left canine and the intercanine distance were measured. These values were used to derive the MCI and establish the amount of sexual dimorphism exhibited by the mandibular canine. Results: The MD crown width of the permanent mandibular right and left canines as well as mandibular intercanine distance of the males was found to be larger in size than in the females. The right mandibular canine exhibited 8.42% of sexual dimorphism while the left mandibular canine exhibited 8.40% of sexual dimorphism. The intercanine distance showed 2.75% of sexual dimorphism. The value of standard MCI derived using the formula devised by Rao et al. was 0.254 mm for the population residing in the Gandhinagar district. Conclusion: The present study supports the usefulness of the MCI in gender determination. The method of using mandibular canine indices is advantageous as it is easy, rapid, and cost-effective, requires no elaborate apparatus, and is suited for situations where large a number of samples have to be analyzed. PMID:29657490

Population-based worksite obesity management interventions: a qualitative case study.

PubMed

Romney, Martha C; Thomson, Erin; Kash, Kathryn

2011-06-01

Due to the increased prevalence of obesity and associated direct and indirect costs to employers, weight management programs have become an integral component of employer and insurer benefits plans. The programs vary in foci, scope, breadth, and implementation. The aim of this study was to explore promising employer-sponsored population-based obesity management programs. A case study that utilized a telephonic semi-structured questionnaire was conducted with small and large organizations located in different regions of the United States that had been recruited to participate. Eight employers and 1 health care advocacy coalition who met the inclusion criteria were interviewed about features of their weight management programs. The case study revealed a number of themes consistent with reports in the literature and reflecting cited best practices. Key findings include confirmation that weight management is a significant component of the wellness strategy in all participating organizations because employers are invested in population health programs and cost savings. Based upon their experience and knowledge, occupational health specialists are responsible for designing, implementing, managing, and evaluating employee health programs. Almost all employers utilize electronic media as a prominent component of wellness and disease management initiatives. Experience has shown that incentives-both financial and nonmonetary-are effective motivators for employee engagement and outcomes. However, while employers report success, favorable outcomes have been difficult to quantify.

Hyperthyroidism and erectile dysfunction: a population-based case-control study.

PubMed

Keller, J; Chen, Y-K; Lin, H-C

2012-01-01

Dysthyroidism has been highlighted as a common endocrine disorder associated with erectile dysfunction (ED); however, to date, no large-scale population-based study has investigated the association between hyperthyroidism and ED. This case-control study aimed to explore the association between ED and hyperthyroidism using a population-based data set. In total, 6310 adult patients who received new diagnoses of ED were recruited as cases together with 18 930 matched enrollees with no history of ED who served as controls. Conditional logistic regressions were conducted to explore the association between ED and having been previously diagnosed with hyperthyroidism. In total, 569 (2.3%) of the 25 240 sampled subjects had been diagnosed with hyperthyroidism before the index date; hyperthyroidism was found in 207 (3.3%) cases and 362 (1.90%) controls. After adjusting for potential confounding factors, the odds ratio (OR) of prior hyperthyroidism among cases was 1.64 (95% confidence interval=1.37-1.96, P<0.001) than that of controls. No association was detected between prior hyperthyroidism and ED for the 18-30, 30-39 and >70 age groups. Subjects aged between 60 and 69 years had the highest ORs for prior hyperthyroidism among cases when compared to controls (OR=1.84; 95% confidence interval=1.20-2.84; P<0.001). Our study further confirms the existence of an association between ED and prior hyperthyroidism.

Greater Cincinnati/Northern Kentucky Stroke Study: volume of first-ever ischemic stroke among blacks in a population-based study.

PubMed

Kissela, B; Broderick, J; Woo, D; Kothari, R; Miller, R; Khoury, J; Brott, T; Pancioli, A; Jauch, E; Gebel, J; Shukla, R; Alwell, K; Tomsick, T

2001-06-01

The volume of ischemic stroke on CT scans has been studied in a standardized fashion in acute stroke therapy trials with median volumes between 10.5 to 55 cm(3). The volume of first-ever ischemic stroke in the population is not known. The first phase of the population-based Greater Cincinnati/Northern Kentucky Stroke Study identified all ischemic strokes occurring in blacks in the greater Cincinnati region between January and June of 1993. The patients in this phase of the study who had a first-ever ischemic clinical stroke were identified, and the volume of ischemic stroke was measured. There were 257 verified clinical cases of ischemic stroke, of which 181 had a first-ever ischemic infarct. Imaging was available for 150 of these patients, and 79 had an infarct on the CT or MRI study that was definitely or possibly related to the clinical symptoms. For these patients, volumetric measurements were performed by means of the modified ellipsoid method. The median volume of first-ever ischemic stroke for the 79 patients was 2.5 cm(3) (interquartile range, 0.5 to 8.8 cm(3)). There was a significant relation between location of lesion and infarct size (P<0.001) and between volume and mechanism of stroke (P=0.001). The volume of first-ever ischemic stroke among blacks in our population-based study is smaller than has been previously reported in acute stroke therapy trials. The large proportion of small, mild strokes in blacks may be an important reason for the low percentage of patients who meet the inclusion criteria for tissue plasminogen activator. Further study is necessary to see if these results are generalizable to a multiracial population.

A population-based study of cognitive impairment in socially vulnerable adults in Argentina. The Matanza Riachuelo study preliminary results

PubMed Central

Bartoloni, Leonardo; Blatt, Graciela; Insua, Iván; Furman, Mariano; González, María Agustina; Hermann, Bárbara; Kesselman, Mariana; Massautis, Alicia; Reinado, Alejandra; Senas, Patricia; Yavitz, Claudia; Lejarraga, Horacio; Nunes, Fernando; Arizaga, Raúl Luciano; Allegri, Ricardo F

2014-01-01

Population aging has taken place intensively worldwide, even in developing countries. These countries have population groups with low resources and basic unmet needs that are frequently omitted from epidemiological studies. Objective The purpose of this study was to determine the prevalence of cognitive impairment (CI) and dementia in an economic and socially vulnerable population from Argentina. Methods A door-to-door observational population-based survey among adults over 60 years of cognitive impairment and dementia in the social vulnerable area of the Matanza Riachuelo Basin, in the suburban area of Buenos Aires, Argentina was conducted. Trained psychologists interviewed subjects and a proxy informant. A standardized protocol including a socio-demographic questionnaire, the Mini-Mental State Examination, the Geriatric Depression Scale and a functional inventory for IADL and ADL was administered. Diagnoses were divided into three general categories: normal cognitive function, cognitive impairment-no dementia (CIND) and dementia. Results and Conclusions A total of 2437 elderly persons were assessed, of which 73.6% fulfilled inclusion criteria. The prevalence of CI among those over 60 was 26.4% (18.1% CIND and 8.3% dementia) with higher prevalence of dementia in younger individuals than rates reported in developed counties, probably due to low control of vascular risk factors. This information can help inform health public decisions in the generation of programs and plans for the prevention, diagnosis and treatment of cognitive impairment in this type of socially vulnerable population. PMID:29213923

A population-based study of cognitive impairment in socially vulnerable adults in Argentina. The Matanza Riachuelo study preliminary results.

PubMed

Bartoloni, Leonardo; Blatt, Graciela; Insua, Iván; Furman, Mariano; González, María Agustina; Hermann, Bárbara; Kesselman, Mariana; Massautis, Alicia; Reinado, Alejandra; Senas, Patricia; Yavitz, Claudia; Lejarraga, Horacio; Nunes, Fernando; Arizaga, Raúl Luciano; Allegri, Ricardo F

2014-01-01

Population aging has taken place intensively worldwide, even in developing countries. These countries have population groups with low resources and basic unmet needs that are frequently omitted from epidemiological studies. The purpose of this study was to determine the prevalence of cognitive impairment (CI) and dementia in an economic and socially vulnerable population from Argentina. A door-to-door observational population-based survey among adults over 60 years of cognitive impairment and dementia in the social vulnerable area of the Matanza Riachuelo Basin, in the suburban area of Buenos Aires, Argentina was conducted. Trained psychologists interviewed subjects and a proxy informant. A standardized protocol including a socio-demographic questionnaire, the Mini-Mental State Examination, the Geriatric Depression Scale and a functional inventory for IADL and ADL was administered. Diagnoses were divided into three general categories: normal cognitive function, cognitive impairment-no dementia (CIND) and dementia. A total of 2437 elderly persons were assessed, of which 73.6% fulfilled inclusion criteria. The prevalence of CI among those over 60 was 26.4% (18.1% CIND and 8.3% dementia) with higher prevalence of dementia in younger individuals than rates reported in developed counties, probably due to low control of vascular risk factors. This information can help inform health public decisions in the generation of programs and plans for the prevention, diagnosis and treatment of cognitive impairment in this type of socially vulnerable population.

Waterloo Eye Study: data abstraction and population representation.

PubMed

Machan, Carolyn M; Hrynchak, Patricia K; Irving, Elizabeth L

2011-05-01

To determine data quality in the Waterloo Eye Study (WatES) and compare the WatES age/sex distribution to the general population. Six thousand three hundred ninety-seven clinic files were reviewed at the University of Waterloo, School of Optometry. Abstracted information included patient age, sex, presenting chief complaint, entering spectacle prescription, refraction, binocular vision, and disease data. Mean age and age distributions were determined for the entire study group and both sexes. These results were compared with Statistics Canada (2006) estimates and information on Canadian optometric practices. Inter- and intraabstractor reliability was determined through double entry of 425 and 50 files, respectively; the Cohen kappa statistic (K) was calculated for qualitative data and the intraclass correlation coefficient (ICC) for quantitative data. Availability of data within the files was determined through missing data rates. The age of the patients in the WatES ranged from 0.2 to 93.9 years (mean age, 42.5 years), with all age groups younger than 85 years well represented. Females comprised 54.1% and males 45.9% of the study group. There were more older patients (>65 years) and younger patients (<10 years) than in the population at large. K values were highest for demographic information (e.g., sex, 0.96) and averaged slightly less for most clinical data requiring some abstractor interpretation (0.71 to 1.00). The two lowest interabstractor values, migraine (0.41) and smoking (0.26), had low reporting frequencies and definition ambiguity between abstractors. Intraclass correlation coefficient values were >0.90 for all but one continuous data type. Missing data rates were <2% for all but near phoria, which was 7.4%. The WatES database includes patients from all age groups and both sexes. It provides a fair representation of optometric patients in Canada. Its large sample size, good interabstractor repeatability, and low missing data rates demonstrates

Mysid Population Responses to Resource Limitation Differ from those Predicted by Cohort Studies

EPA Science Inventory

Effects of anthropogenic stressors on animal populations are often evaluated by assembling vital rate responses from isolated cohort studies into a single demographic model. However, models constructed from cohort studies are difficult to translate into ecological predictions be...

Methods and background characteristics of the TOHNN study: a population-based study of oral health conditions in northern Norway

PubMed Central

Holde, Gro Eirin; Oscarson, Nils; Tillberg, Anders; Marstrander, Peter; Jönsson, Birgitta

2016-01-01

Objectives The aim of the Tromstannen – Oral Health in Northern Norway (TOHNN) study was to investigate oral health and dental-related diseases in an adult population. This article provides an overview of the background of the study and a description of the sample characteristics and methods employed in data collection. Study design Cross-sectional population-based study including a questionnaire and clinical dental examination. Methods A randomly selected sample of 2,909 individuals (20–79 years old) drawn from the population register was invited to participate in the study. The data were collected between October 2013 and November 2014 in Troms County in northern Norway. The questionnaire focused on oral health-related behaviours and attitudes, oral health-related quality of life, sense of coherence, dental anxiety and symptoms from the temporomandibular joint. The dental examinations, including radiographs, were conducted by 11 dental teams in 5 dental offices. The examination comprised of registration of dental caries, full mouth periodontal status, temporomandibular disorders, mucosal lesions and height and weight. The participants were grouped by age (20–34, 35–49, 50–64 and 65–79) and ethnicity (Norwegian, Sámi, other European and other world). Results From the original sample of 2,909 individuals, 1,986 (68.3%) people participated, of whom 1,019 (51.3%) were women. The highest attendance rate was among women 20–34 years old (80.3%) and the lowest in the oldest age group of women (55.4%). There was no difference in response rate between rural and urban areas. There was a positive correlation between population size and household gross income (p < 0.001) and education level (p < 0.001). The majority of Sámi resided in smaller municipalities. In larger cities, most participants used private dental health care services, whereas, in rural areas, most participants used the public dental health care service. Conclusion The TOHNN study has the

The dynamics of zooxanthellae populations: A long-term study in the field

PubMed

Fagoonee; Wilson; Hassell; Turner

1999-02-05

Coral bleaching characterized by the expulsion of symbiotic algae (zooxanthellae) is an increasing problem worldwide. Global warming has been implicated as one cause, but the phenomenon cannot be fully comprehended without an understanding of the variability of zooxanthellae populations in field conditions. Results from a 6-year field study are presented, providing evidence of density regulation but also of large variability in the zooxanthellae population with regular episodes of very low densities. These bleaching events are likely to be part of a constant variability in zooxanthellae density caused by environmental fluctuations superimposed on a strong seasonal cycle in abundance.

Infantile autism in children of immigrant parents. A population-based study from Göteborg, Sweden.

PubMed

Gillberg, C; Steffenburg, S; Börjesson, B; Andersson, L

1987-06-01

A population-based study of infantile autism from western Sweden has been completed. Urban children with autism more often than age-matched children in the general population had immigrant parents from 'exotic' countries. No such trend was seen in rural children with infantile autism.

Craniofacial morphologic parameters in a Persian population: an anthropometric study.

PubMed

Amini, Fariborz; Mashayekhi, Ziba; Rahimi, Hajir; Morad, Golnaz

2014-09-01

Limited data are available regarding the reference ranges of facial proportions of the Persian population in Iran. This study aimed to establish the reference range of craniofacial anthropometric measurements in an adult Iranian population. On 100 individuals (men = women), aged 18 to 30 years with normal faces and occlusions, 34 linear and 7 angular measurements as well as 24 indices were calculated. The difference of measurements between men and women were evaluated by paired t-test. The data were compared with the norms of North American whites using 1-sample t-test. The subjects belonged to 5 ethnic groups (57% from Fars, 14% from Kord, 11% from Azari, 10% from Gilaki-Mazani, and 2% from Lor). All head measurements were greater in men except for the head index and the head height. The subjects had leptoprosopic faces. The intercanthal width was almost one third of the biocular width and greater than the eye fissure length. Although the nose width of women was significantly smaller, both sexes had leptorrhine noses. The chin height and lower chin height were greater in men. In comparison with North American whites, considerable differences were found regarding head height and width, biocular width, nose height, face height, mouth width, and upper chin height. In conclusion, the reference range of craniofacial anthropometric measurements established for the Iranian population might be efficiently used for esthetic treatments.

Utilization and costs of antipsychotic agents: a Canadian population-based study, 1996-2006.

PubMed

Alessi-Severini, Silvia; Biscontri, Robert G; Collins, David M; Kozyrskyj, Anita; Sareen, Jitender; Enns, Murray W

2008-05-01

This study evaluated the prescribing patterns and costs for antipsychotic agents in the population of the Canadian province of Manitoba over the past decade. A population-based study of antipsychotic utilization and costs was conducted on data collected from the administrative databases of the Manitoba Population Health Data Repository and the Statistics Canada census between index years 1996 and 2006 (April 1, 1995, through March 31, 2006). The total annual number of antipsychotic prescriptions dispensed in Manitoba increased by 227% between 1996 and 2006, and the prevalence of antipsychotic users increased by 62% over the same time interval. The fastest-growing segment of antipsychotic users in Manitoba appears to be young males, who increased from .16% in 1996 to .88% in 2006. The highest numbers of prescriptions were reported for schizophrenia, dementia, and conduct disorder. Annual expenditures for antipsychotics increased from $1.7 million in 1996 to $22.0 million in 2006 (expenditures are in Canadian dollars). The cost of second-generation agents reached 80% of total antipsychotic expenditures in 2006; risperidone was the most prescribed agent in all age groups of patients. The per-patient annual cost of antipsychotic pharmacotherapy increased by approximately 680% between 1996 and 2006 in Manitoba. The number of antipsychotic prescriptions and the prevalence of users of antipsychotic medications increased significantly in Manitoba over the study period, despite a steady-state population of approximately 1.2 million. Incremental costs relative to the use of antipsychotic medications can be explained by the market penetration of the second-generation agents and their expanded use in the treatment of various diagnoses.

A theoretical study of alpha star populations in loaded nuclear emulsions

USGS Publications Warehouse

Senftle, F.E.; Farley, T.A.; Stieff, L.R.

1954-01-01

This theoretical study of the alpha star populations in loaded emulsions was undertaken in an effort to find a quantitative method for the analysis of less than microgram amounts of thorium in the presence of larger amounts of uranium. Analytical expressions for each type of star from each of the significantly contributing members of the uranium and thorium series as well as summation formulas for the whole series have been computed. The analysis for thorium may be made by determining the abundance of five-branched stars in a loaded nuclear emulsion and comparing of observed and predicted star populations. The comparison may also be used to check the half-lives of several members of the uranium and thorium series. ?? 1954.

Japanese population structure, based on SNP genotypes from 7003 individuals compared to other ethnic groups: effects on population-based association studies.

PubMed

Yamaguchi-Kabata, Yumi; Nakazono, Kazuyuki; Takahashi, Atsushi; Saito, Susumu; Hosono, Naoya; Kubo, Michiaki; Nakamura, Yusuke; Kamatani, Naoyuki

2008-10-01

Because population stratification can cause spurious associations in case-control studies, understanding the population structure is important. Here, we examined Japanese population structure by "Eigenanalysis," using the genotypes for 140,387 SNPs in 7003 Japanese individuals, along with 60 European, 60 African, and 90 East-Asian individuals, in the HapMap project. Most Japanese individuals fell into two main clusters, Hondo and Ryukyu; the Hondo cluster includes most of the individuals from the main islands in Japan, and the Ryukyu cluster includes most of the individuals from Okinawa. The SNPs with the greatest frequency differences between the Hondo and Ryukyu clusters were found in the HLA region in chromosome 6. The nonsynonymous SNPs with the greatest frequency differences between the Hondo and Ryukyu clusters were the Val/Ala polymorphism (rs3827760) in the EDAR gene, associated with hair thickness, and the Gly/Ala polymorphism (rs17822931) in the ABCC11 gene, associated with ear-wax type. Genetic differentiation was observed, even among different regions in Honshu Island, the largest island of Japan. Simulation studies showed that the inclusion of different proportions of individuals from different regions of Japan in case and control groups can lead to an inflated rate of false-positive results when the sample sizes are large.

Population Pharmacokinetic Model of Doxycycline Plasma Concentrations Using Pooled Study Data

PubMed Central

Wojciechowski, Jessica; Mudge, Stuart; Upton, Richard N.; Foster, David J. R.

2017-01-01

ABSTRACT The literature presently lacks a population pharmacokinetic analysis of doxycycline. This study aimed to develop a population pharmacokinetic model of doxycycline plasma concentrations that could be used to assess the power of bioequivalence between Doryx delayed-release tablets and Doryx MPC. Doxycycline pharmacokinetic data were available from eight phase 1 clinical trials following single/multiple doses of conventional-release doxycycline capsules, Doryx delayed-release tablets, and Doryx MPC under fed and fasted conditions. A population pharmacokinetic model was developed in a stepwise manner using NONMEM, version 7.3. The final covariate model was developed according to a forward inclusion (P < 0.01) and then backward deletion (P < 0.001) procedure. The final model was a two-compartment model with two-transit absorption compartments. Structural covariates in the base model included formulation effects on relative bioavailability (F), absorption lag (ALAG), and the transit absorption rate (KTR) under the fed status. An absorption delay (lag) for the fed status (FTLAG2 = 0.203 h) was also included in the model as a structural covariate. The fed status was observed to decrease F by 10.5%, and the effect of female sex was a 14.4% increase in clearance. The manuscript presents the first population pharmacokinetic model of doxycycline plasma concentrations following oral doxycycline administration. The model was used to assess the power of bioequivalence between Doryx delayed-release tablets and Doryx MPC, and it could potentially be used to critically examine and optimize doxycycline dose regimens. PMID:28052851

Ancestry estimation and control of population stratification for sequence-based association studies.

PubMed

Wang, Chaolong; Zhan, Xiaowei; Bragg-Gresham, Jennifer; Kang, Hyun Min; Stambolian, Dwight; Chew, Emily Y; Branham, Kari E; Heckenlively, John; Fulton, Robert; Wilson, Richard K; Mardis, Elaine R; Lin, Xihong; Swaroop, Anand; Zöllner, Sebastian; Abecasis, Gonçalo R

2014-04-01

Estimating individual ancestry is important in genetic association studies where population structure leads to false positive signals, although assigning ancestry remains challenging with targeted sequence data. We propose a new method for the accurate estimation of individual genetic ancestry, based on direct analysis of off-target sequence reads, and implement our method in the publicly available LASER software. We validate the method using simulated and empirical data and show that the method can accurately infer worldwide continental ancestry when used with sequencing data sets with whole-genome shotgun coverage as low as 0.001×. For estimates of fine-scale ancestry within Europe, the method performs well with coverage of 0.1×. On an even finer scale, the method improves discrimination between exome-sequenced study participants originating from different provinces within Finland. Finally, we show that our method can be used to improve case-control matching in genetic association studies and to reduce the risk of spurious findings due to population structure.

Opioid system genes in alcoholism: a case-control study in Croatian population.

PubMed

Cupic, B; Stefulj, J; Zapletal, E; Matosic, A; Bordukalo-Niksic, T; Cicin-Sain, L; Gabrilovac, J

2013-10-01

Due to their involvement in dependence pathways, opioid system genes represent strong candidates for association studies investigating alcoholism. In this study, single nucleotide polymorphisms within the genes for mu (OPRM1) and kappa (OPRK1) opioid receptors and precursors of their ligands - proopiomelanocortin (POMC), coding for beta-endorphin and prodynorphin (PDYN) coding for dynorphins, were analyzed in a case-control study that included 354 male alcohol-dependent and 357 male control subjects from Croatian population. Analysis of allele and genotype frequencies of the selected polymorphisms of the genes OPRM1/POMC and OPRK1/PDYN revealed no differences between the tested groups. The same was true when alcohol-dependent persons were subdivided according to the Cloninger's criteria into type-1 and type-2 groups, known to differ in the extent of genetic control. Thus, the data obtained suggest no association of the selected polymorphisms of the genes OPRM1/POMC and OPRK1/PDYN with alcoholism in Croatian population. Copyright © 2013 Elsevier Ltd. All rights reserved.

Validation of Surrogates of Urine Osmolality in Population Studies.

PubMed

Youhanna, Sonia; Bankir, Lise; Jungers, Paul; Porteous, David; Polasek, Ozren; Bochud, Murielle; Hayward, Caroline; Devuyst, Olivier

2017-01-01

The importance of vasopressin and/or urine concentration in various kidney, cardiovascular, and metabolic diseases has been emphasized recently. Due to technical constraints, urine osmolality (Uosm), a direct reflect of urinary concentrating activity, is rarely measured in epidemiologic studies. We analyzed 2 possible surrogates of Uosm in 4 large population-based cohorts (total n = 4,247) and in patients with chronic kidney disease (CKD, n = 146). An estimated Uosm (eUosm) based on the concentrations of sodium, potassium, and urea, and a urine concentrating index (UCI) based on the ratio of creatinine concentrations in urine and plasma were compared to the measured Uosm (mUosm). eUosm is an excellent surrogate of mUosm, with a highly significant linear relationship and values within 5% of mUosm (r = 0.99 or 0.98 in each population cohort). Bland-Altman plots show a good agreement between eUosm and mUosm with mean differences between the 2 variables within ±24 mmol/L. This was verified in men and women, in day and night urine samples, and in CKD patients. The relationship of UCI with mUosm is also significant but is not linear and exhibits more dispersed values. Moreover, the latter index is no longer representative of mUosm in patients with CKD as it declines much more quickly with declining glomerular filtration rate than mUosm. The eUosm is a valid marker of urine concentration in population-based and CKD cohorts. The UCI can provide an estimate of urine concentration when no other measurement is available, but should be used only in subjects with normal renal function. © 2017 S. Karger AG, Basel.

Developing Exon-Primed Intron-Crossing (EPIC) markers for population genetic studies in three Aedes disease vectors.

PubMed

White, Vanessa Linley; Endersby, Nancy Margaret; Chan, Janice; Hoffmann, Ary Anthony; Weeks, Andrew Raymond

2015-03-01

Aedes aegypti, Aedes notoscriptus, and Aedes albopictus are important vectors of many arboviruses implicated in human disease such as dengue fever. Genetic markers applied across vector species can provide important information on population structure, gene flow, insecticide resistance, and taxonomy, however, robust microsatellite markers have proven difficult to develop in these species and mosquitoes generally. Here we consider the utility and transferability of 15 Ribosome protein (Rp) Exon-Primed Intron-Crossing (EPIC) markers for population genetic studies in these 3 Aedes species. Rp EPIC markers designed for Ae. aegypti also successfully amplified populations of the sister species, Ae. albopictus, as well as the distantly related species, Ae. notoscriptus. High SNP and good indel diversity in sequenced alleles plus support for amplification of the same regions across populations and species were additional benefits of these markers. These findings point to the general value of EPIC markers in mosquito population studies. © 2014 Institute of Zoology, Chinese Academy of Sciences.

Non-fatal disease burden for subtypes of depressive disorder: population-based epidemiological study.

PubMed

Biesheuvel-Leliefeld, Karolien E M; Kok, Gemma D; Bockting, Claudi L H; de Graaf, Ron; Ten Have, Margreet; van der Horst, Henriette E; van Schaik, Anneke; van Marwijk, Harm W J; Smit, Filip

2016-05-12

Major depression is the leading cause of non-fatal disease burden. Because major depression is not a homogeneous condition, this study estimated the non-fatal disease burden for mild, moderate and severe depression in both single episode and recurrent depression. All estimates were assessed from an individual and a population perspective and presented as unadjusted, raw estimates and as estimates adjusted for comorbidity. We used data from the first wave of the second Netherlands-Mental-Health-Survey-and-Incidence-Study (NEMESIS-2, n = 6646; single episode Diagnostic and Statistical Manual (DSM)-IV depression, n = 115; recurrent depression, n = 246). Disease burden from an individual perspective was assessed as 'disability weight * time spent in depression' for each person in the dataset. From a population perspective it was assessed as 'disability weight * time spent in depression *number of people affected'. The presence of mental disorders was assessed with the Composite International Diagnostic Interview (CIDI) 3.0. Single depressive episodes emerged as a key driver of disease burden from an individual perspective. From a population perspective, recurrent depressions emerged as a key driver. These findings remained unaltered after adjusting for comorbidity. The burden of disease differs between the subtype of depression and depends much on the choice of perspective. The distinction between an individual and a population perspective may help to avoid misunderstandings between policy makers and clinicians.

Incidence of Melanoma in Children: A Population-Based Study in Olmsted County, Minnesota.

PubMed

Lowe, Garrett C; Brewer, Jerry D; Peters, Margot S; Davis, Dawn M R

2015-01-01

The incidence of melanoma has been rising in the United States, with conflicting evidence regarding trends in children. We identified patients 0 to 17 years old with a diagnosis of melanoma from January 1, 1970, through December 31, 2010, in Olmsted County, Minnesota. Information on survival and demographic characteristics was abstracted, and estimates of true incidence were calculated. The estimated true incidence of melanoma in children from 1970 to 2010 was found to be 0.62 per 100,000 girls and 0.45 per 100,000 boys. The incidence of melanoma in this population did not increase with time after adjusting for age and sex. Only one case of metastatic disease (lymph node) was identified. Girls were more commonly affected and the mean age of disease onset was 14 years. Five of the seven melanomas in this population arose in association with a nevus, and none involved the trunk. Overall and disease-specific survival rates were not calculated because all patients studied were alive at the last follow-up. The estimated true incidence rates of pediatric melanoma from our population-based study in Olmsted County, Minnesota, appear stable. This finding is in contrast to our prior research showing rapidly increasing incidence rates of melanoma in young and middle-aged adults from the same population. © 2015 Wiley Periodicals, Inc.

Study of a mixed dispersal population dynamics model

DOE PAGES

Chugunova, Marina; Jadamba, Baasansuren; Kao, Chiu -Yen; ...

2016-08-27

In this study, we consider a mixed dispersal model with periodic and Dirichlet boundary conditions and its corresponding linear eigenvalue problem. This model describes the time evolution of a population which disperses both locally and non-locally. We investigate how long time dynamics depend on the parameter values. Furthermore, we study the minimization of the principal eigenvalue under the constraints that the resource function is bounded from above and below, and with a fixed total integral. Biologically, this minimization problem is motivated by the question of determining the optimal spatial arrangement of favorable and unfavorable regions for the species to diemore » out more slowly or survive more easily. Our numerical simulations indicate that the optimal favorable region tends to be a simply-connected domain. Numerous results are shown to demonstrate various scenarios of optimal favorable regions for periodic and Dirichlet boundary conditions.« less

Establishing multiple omics baselines for three Southeast Asian populations in the Singapore Integrative Omics Study.

PubMed

Saw, Woei-Yuh; Tantoso, Erwin; Begum, Husna; Zhou, Lihan; Zou, Ruiyang; He, Cheng; Chan, Sze Ling; Tan, Linda Wei-Lin; Wong, Lai-Ping; Xu, Wenting; Moong, Don Kyin Nwe; Lim, Yenly; Li, Bowen; Pillai, Nisha Esakimuthu; Peterson, Trevor A; Bielawny, Tomasz; Meikle, Peter J; Mundra, Piyushkumar A; Lim, Wei-Yen; Luo, Ma; Chia, Kee-Seng; Ong, Rick Twee-Hee; Brunham, Liam R; Khor, Chiea-Chuen; Too, Heng Phon; Soong, Richie; Wenk, Markus R; Little, Peter; Teo, Yik-Ying

2017-09-21

The Singapore Integrative Omics Study provides valuable insights on establishing population reference measurement in 364 Chinese, Malay, and Indian individuals. These measurements include > 2.5 millions genetic variants, 21,649 transcripts expression, 282 lipid species quantification, and 284 clinical, lifestyle, and dietary variables. This concept paper introduces the depth of the data resource, and investigates the extent of ethnic variation at these omics and non-omics biomarkers. It is evident that there are specific biomarkers in each of these platforms to differentiate between the ethnicities, and intra-population analyses suggest that Chinese and Indians are the most biologically homogeneous and heterogeneous, respectively, of the three groups. Consistent patterns of correlations between lipid species also suggest the possibility of lipid tagging to simplify future lipidomics assays. The Singapore Integrative Omics Study is expected to allow the characterization of intra-omic and inter-omic correlations within and across all three ethnic groups through a systems biology approach.The Singapore Genome Variation projects characterized the genetics of Singapore's Chinese, Malay, and Indian populations. The Singapore Integrative Omics Study introduced here goes further in providing multi-omic measurements in individuals from these populations, including genetic, transcriptome, lipidome, and lifestyle data, and will facilitate the study of common diseases in Asian communities.

Socio-Cultural Case Studies for Population Education in Morocco, Peru, Rwanda and the United Republic of Tanzania. Co-ordinated Action Programme for the Advancement of Population Education (CAPAPE).

ERIC Educational Resources Information Center

United Nations Educational, Scientific, and Cultural Organization, Paris (France). Population Education Section.

Developed to serve as a guide, this document contains four case studies which demonstrate the application of a conceptual and methodological reference model which promotes the use of socio-cultural research in national population education projects. Information obtained from these kinds of studies can be used in developing population education…

Fish population studies using parasites from the Southeastern Pacific Ocean: considering host population changes and species body size as sources of variability of parasite communities.

PubMed

George-Nascimento, Mario; Oliva, Marcelo

2015-01-01

Research using parasites in fish population studies in the South Eastern Pacific (SEP) is summarized. There are 27 such studies (snapshots mainly) in single host species sampled at different geographic localities and at somewhat similar times. They have been devoted mainly to economically important species, though others on coastal and intertidal fish or on less- or non-commercial species provide insights on scales of temporal and spatial variation of parasite infracommunities. Later, we assess whether the probability of harbouring parasites depends on the host species body size. Our results indicate that a stronger tool for fish population studies may be developed under regular (long term) scrutiny of parasite communities, especially of small fish host species, due to their larger variability in richness, abundance and total biomass, than in large fish species. Finally, it might also be necessary to consider the effects of fishing on parasite communities as well as the natural oscillations (coupled or not) of host and parasite populations.

Sub-sampling genetic data to estimate black bear population size: A case study

USGS Publications Warehouse

Tredick, C.A.; Vaughan, M.R.; Stauffer, D.F.; Simek, S.L.; Eason, T.

2007-01-01

Costs for genetic analysis of hair samples collected for individual identification of bears average approximately US$50 [2004] per sample. This can easily exceed budgetary allowances for large-scale studies or studies of high-density bear populations. We used 2 genetic datasets from 2 areas in the southeastern United States to explore how reducing costs of analysis by sub-sampling affected precision and accuracy of resulting population estimates. We used several sub-sampling scenarios to create subsets of the full datasets and compared summary statistics, population estimates, and precision of estimates generated from these subsets to estimates generated from the complete datasets. Our results suggested that bias and precision of estimates improved as the proportion of total samples used increased, and heterogeneity models (e.g., Mh[CHAO]) were more robust to reduced sample sizes than other models (e.g., behavior models). We recommend that only high-quality samples (>5 hair follicles) be used when budgets are constrained, and efforts should be made to maximize capture and recapture rates in the field.

A genome-wide association study on photic sneeze syndrome in a Japanese population.

PubMed

Sasayama, Daimei; Asano, Shinya; Nogawa, Shun; Takahashi, Shoko; Saito, Kenji; Kunugi, Hiroshi

2018-03-20

Photic sneeze syndrome (PSS) is characterized by a tendency to sneeze when the eye is exposed to bright light. Recent genome-wide association studies (GWASs) have identified single-nucleotide polymorphisms (SNPs) associated with PSS in Caucasian populations. We performed a GWAS on PSS in Japanese individuals who responded to a web-based survey and provided saliva samples. After quality control, genotype data of 210,086 SNPs in 11,409 individuals were analyzed. The overall prevalence of PSS was 3.2%. Consistent with previous reports, SNPs at 3p12.1 were associated with PSS at genome-wide significance (p < 5.0 × 10 -8 ). Furthermore, two novel loci at 9q34.2 and 4q35.2 reached suggestive significance (p < 5.0 × 10 -6 ). Our data also provided evidence supporting the two additional SNPs on 2q22.3 and 9q33.2 reportedly associated with PSS. Our study reproduced previous findings in Caucasian populations and further suggested novel PSS loci in the Japanese population.

Neighborhood social capital is associated with participation in health checks of a general population: a multilevel analysis of a population-based lifestyle intervention- the Inter99 study.

PubMed

Bender, Anne Mette; Kawachi, Ichiro; Jørgensen, Torben; Pisinger, Charlotta

2015-07-22

Participation in population-based preventive health check has declined over the past decades. More research is needed to determine factors enhancing participation. The objective of this study was to examine the association between two measures of neighborhood level social capital on participation in the health check phase of a population-based lifestyle intervention. The study population comprised 12,568 residents of 73 Danish neighborhoods in the intervention group of a large population-based lifestyle intervention study - the Inter99. Two measures of social capital were applied; informal socializing and voting turnout. In a multilevel analysis only adjusting for age and sex, a higher level of neighborhood social capital was associated with higher probability of participating in the health check. Inclusion of both individual socioeconomic position and neighborhood deprivation in the model attenuated the coefficients for informal socializing, while voting turnout became non-significant. Higher level of neighborhood social capital was associated with higher probability of participating in the health check phase of a population-based lifestyle intervention. Most of the association between neighborhood social capital and participation in preventive health checks can be explained by differences in individual socioeconomic position and level of neighborhood deprivation. Nonetheless, there seems to be some residual association between social capital and health check participation, suggesting that activating social relations in the community may be an avenue for boosting participation rates in population-based health checks. ClinicalTrials.gov (registration no. NCT00289237 ).

[Impact of disabling chronic pain: results of a cross-sectional population study with face-to-face interview].

PubMed

Cabrera-Leon, Andrés; Cantero-Braojos, Miguel Ángel

2017-11-16

To assess the impact of disabling chronic pain (DCP) on quality of life, work, consumption of medication and usage of health services. Cross-sectional population study with face-to-face interview. Andalusian Health Survey (2011 edition). 6,507 people over the age of 16 (p=q=0.5; confidence level=95%; sampling error=1.49, design effect=1.52). Not applicable. Dependent variable: DCP: population limited in their activity by any of the CP specified in the survey. quality of life, absence from work, consumption of medication and utilization of health services. Compared to a population without CP, DCP impact is 6 points less on the mental quality of life and 12 points on the physical one, medication consumption is triple, health services utilization is almost double, and long absence from work is triple. On the other hand, a population with nondisabling chronic pain (nDCP) presents similar results to a population without CP. We have considered DCP as another CP category because of its huge impact, as is shown in our study, on the study variables. On the contrary, the population with nDCP does not obtain significant impact differences when compared to the population without CP. Therefore, we believe that Primary Care and Public Health should lead different prevention strategies for DCP as well as for the identification of the nDCP population to decrease its possible deterioration towards DCP. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

Validation study of human figure drawing test in a Colombian school children population.

PubMed

Vélez van Meerbeke, Alberto; Sandoval-Garcia, Carolina; Ibáñez, Milciades; Talero-Gutiérrez, Claudia; Fiallo, Dolly; Halliday, Karen

2011-05-01

The aim of this article was to assess the validity of the emotional and developmental components of the Koppitz human figure drawing test. 2420 children's drawings available in a database resulting from a previous cross sectional study designed to determine the prevalence of neurological diseases in children between 0 and 12 years old in Bogota schools were evaluated. They were scored using the criteria proposed by Koppitz, and classified into 16 groups according to age, gender, and presence/absence of learning or attention problems. The overall results were then compared with the normative study to assess whether descriptive parameters of the two populations were significantly different. There were no significant differences associated with presence/absence of learning and attention disorders or school attended within the overall sample. An Interrater reliability test has been made to assure the homogeneity of scoring by the evaluator team. There were significant differences between this population and that of the original study. New scoring tables contextualized for our population based on the frequency of appearance in this sample are presented. We can conclude that various ethnic, social, and cultural factors can influence the way children draw the human figure. It is thus important to establish local reference values to adequately distinguish between normality and abnormality. The new scoring tables proposed here should be followed up with a clinical study to corroborate their validity.

Population and genomic lessons from genetic analysis of two Indian populations.

PubMed

Juyal, Garima; Mondal, Mayukh; Luisi, Pierre; Laayouni, Hafid; Sood, Ajit; Midha, Vandana; Heutink, Peter; Bertranpetit, Jaume; Thelma, B K; Casals, Ferran

2014-10-01

Indian demographic history includes special features such as founder effects, interpopulation segregation, complex social structure with a caste system and elevated frequency of consanguineous marriages. It also presents a higher frequency for some rare mendelian disorders and in the last two decades increased prevalence of some complex disorders. Despite the fact that India represents about one-sixth of the human population, deep genetic studies from this terrain have been scarce. In this study, we analyzed high-density genotyping and whole-exome sequencing data of a North and a South Indian population. Indian populations show higher differentiation levels than those reported between populations of other continents. In this work, we have analyzed its consequences, by specifically assessing the transferability of genetic markers from or to Indian populations. We show that there is limited genetic marker portability from available genetic resources such as HapMap or the 1,000 Genomes Project to Indian populations, which also present an excess of private rare variants. Conversely, tagSNPs show a high level of portability between the two Indian populations, in contrast to the common belief that North and South Indian populations are genetically very different. By estimating kinship from mates and consanguinity in our data from trios, we also describe different patterns of assortative mating and inbreeding in the two populations, in agreement with distinct mating preferences and social structures. In addition, this analysis has allowed us to describe genomic regions under recent adaptive selection, indicating differential adaptive histories for North and South Indian populations. Our findings highlight the importance of considering demography for design and analysis of genetic studies, as well as the need for extending human genetic variation catalogs to new populations and particularly to those with particular demographic histories.

Using natural language processing for identification of herpes zoster ophthalmicus cases to support population-based study.

PubMed

Zheng, Chengyi; Luo, Yi; Mercado, Cheryl; Sy, Lina; Jacobsen, Steven J; Ackerson, Brad; Lewin, Bruno; Tseng, Hung Fu

2018-06-19

Diagnosis codes are inadequate for accurately identifying herpes zoster ophthalmicus (HZO). There is significant lack of population-based studies on HZO due to the high expense of manual review of medical records. To assess whether HZO can be identified from the clinical notes using natural language processing (NLP). To investigate the epidemiology of HZO among HZ population based on the developed approach. A retrospective cohort analysis. A total of 49,914 southern California residents aged over 18 years, who had a new diagnosis of HZ. An NLP-based algorithm was developed and validated with the manually curated validation dataset (n=461). The algorithm was applied on over 1 million clinical notes associated with the study population. HZO versus non-HZO cases were compared by age, sex, race, and comorbidities. We measured the accuracy of NLP algorithm. NLP algorithm achieved 95.6% sensitivity and 99.3% specificity. Compared to the diagnosis codes, NLP identified significant more HZO cases among HZ population (13.9% versus 1.7%). Compared to the non-HZO group, the HZO group was older, had more males, had more Whites, and had more outpatient visits. We developed and validated an automatic method to identify HZO cases with high accuracy. As one of the largest studies on HZO, our finding emphasizes the importance of preventing HZ in the elderly population. This method can be a valuable tool to support population-based studies and clinical care of HZO in the era of big data. This article is protected by copyright. All rights reserved.

Elder Self-Neglect in a Community-Dwelling U.S. Chinese Population: Findings from the Population Study of Chinese Elderly in Chicago (PINE) Study

PubMed Central

Dong, XinQi

2014-01-01

Objectives To examine the prevalence of self-neglect and its specific behaviors in a community-dwelling U.S. Chinese aging population. Design Population-based cohort study. Setting Community-dwelling population of Chinese older adults. Participants 3,159 Chinese older adults in the greater Chicago area interviewed from 2011-2013. Measurements Participant’s personal and home environment was rated based on prevalence of hoarding behavior, personal hygiene, repairs needed on the home, sanitary condition of the home, and adequacy of utilities. Prevalence estimates were presented across self-reported quality-of-life. Results Prevalence of self-neglect was 18.2% for mild self-neglect and 10.9% for moderate/severe self-neglect among Chinese older adults. In terms of specific phenotypes, unsanitary conditions (17.0%) was the most prevalent, followed by need of home repair (16.3%), hoarding behavior (14.9%), poor personal hygiene (11.3%), and inadequate utilities (4.2%). The prevalence of elder self-neglect of all severities and its phenotypes was higher among older adults with fair or poor quality-of-life as compared to that of older adults with good or very good quality-of-life. Lower quality-of-life was significantly associated with and increased risk for self-neglect of all severities (mild self-neglect: OR 1.93, 95% CI 1.26-2.96, p<0.001; moderate/severe self-neglect: OR 3.58, 95% CI 1.79-7.13, p<0.001) and specific personal and environmental hazards. Conclusion Elder self-neglect is prevalent, especially among those with lower levels of quality-of-life. Future research is needed to examine risk/protective factors associated with elder self-neglect. PMID:25439674

The epidemiology of traumatic cervical spine fractures: a prospective population study from Norway.

PubMed

Fredø, Hege Linnerud; Rizvi, Syed Ali Mujtaba; Lied, Bjarne; Rønning, Pål; Helseth, Eirik

2012-12-21

The aim of this study was to estimate the incidence of traumatic cervical spine fractures (CS-fx) in a general population. The incidence of CS-fx in the general population is largely unknown. All CS-fx (C0/C1 to C7/Th1) patients diagnosed with cervical-CT in Southeast Norway (2.7 million inhabitants) during the time period from April 27, 2010-April 26, 2011 were prospectively registered in this observational cohort study. Over a one-year period, 319 patients with CS-fx at one or more levels were registered, constituting an estimated incidence of 11.8/100,000/year. The median age of the patients was 56 years (range 4-101 years), and 68% were males. The relative incidence of CS-fx increased significantly with age. The trauma mechanisms were falls in 60%, motorized vehicle accidents in 21%, bicycling in 8%, diving in 4% and others in 7% of patients. Neurological status was normal in 79%, 5% had a radiculopathy, 8% had an incomplete spinal cord injury (SCI), 2% had a complete SCI, and neurological function could not be determined in 6%. The mortality rates after 1 and 3 months were 7 and 9%, respectively. Among 319 patients, 26.6% were treated with open surgery, 68.7% were treated with external immobilization with a stiff collar and 4.7% were considered stable and not in need of any specific treatment. The estimated incidence of surgically treated CS-fx in our population was 3.1/100,000/year. This study estimates the incidence of traumatic CS-fx in a general Norwegian population to be 11.8/100,000/year. A male predominance was observed and the incidence increased with increasing age. Falls were the most common trauma mechanism, and SCI was observed in 10%. The 1- and 3-month mortality rates were 7 and 9%, respectively. The incidence of open surgery for the fixation of CS-fx in this population was 3.1/100,000/year. This is a prospective observational cohort study and level II-2 according to US Preventive Services Task Force.

Psychedelics and Mental Health: A Population Study

PubMed Central

Krebs, Teri S.; Johansen, Pål-Ørjan

2013-01-01

Background The classical serotonergic psychedelics LSD, psilocybin, mescaline are not known to cause brain damage and are regarded as non-addictive. Clinical studies do not suggest that psychedelics cause long-term mental health problems. Psychedelics have been used in the Americas for thousands of years. Over 30 million people currently living in the US have used LSD, psilocybin, or mescaline. Objective To evaluate the association between the lifetime use of psychedelics and current mental health in the adult population. Method Data drawn from years 2001 to 2004 of the National Survey on Drug Use and Health consisted of 130,152 respondents, randomly selected to be representative of the adult population in the United States. Standardized screening measures for past year mental health included serious psychological distress (K6 scale), mental health treatment (inpatient, outpatient, medication, needed but did not receive), symptoms of eight psychiatric disorders (panic disorder, major depressive episode, mania, social phobia, general anxiety disorder, agoraphobia, posttraumatic stress disorder, and non-affective psychosis), and seven specific symptoms of non-affective psychosis. We calculated weighted odds ratios by multivariate logistic regression controlling for a range of sociodemographic variables, use of illicit drugs, risk taking behavior, and exposure to traumatic events. Results 21,967 respondents (13.4% weighted) reported lifetime psychedelic use. There were no significant associations between lifetime use of any psychedelics, lifetime use of specific psychedelics (LSD, psilocybin, mescaline, peyote), or past year use of LSD and increased rate of any of the mental health outcomes. Rather, in several cases psychedelic use was associated with lower rate of mental health problems. Conclusion We did not find use of psychedelics to be an independent risk factor for mental health problems. PMID:23976938

Realized population change for long-term monitoring: California spotted owl case study

Treesearch

Mary M. Conner; John J. Keane; Claire V. Gallagher; Gretchen Jehle; Thomas E. Munton; Paula A. Shaklee; Ross A. Gerrard

2013-01-01

The annual rate of population change (λt) is a good metric for evaluating population performance because it summarizes survival and recruitment rates and can be used for open populations. Another measure of population performance, realized population change (Δt...

Genome-wide association study reveals regions associated with gestation length in two pig populations.

PubMed

Hidalgo, A M; Lopes, M S; Harlizius, B; Bastiaansen, J W M

2016-04-01

Reproduction traits, such as gestation length (GLE), play an important role in dam line breeding in pigs. The objective of our study was to identify single nucleotide polymorphisms (SNPs) that are associated with GLE in two pig populations. Genotypes and deregressed breeding values were available for 2081 Dutch Landrace-based (DL) and 2301 Large White-based (LW) pigs. We identified two QTL regions for GLE, one in each population. For DL, three associated SNPs were detected in one QTL region spanning 0.52 Mbp on Sus scrofa chromosome (SSC) 2. For LW, four associated SNPs were detected in one region of 0.14 Mbp on SSC5. The region on SSC2 contains the heparin-binding EGF-like growth factor (HBEGF) gene, which promotes embryo implantation and has been described to be involved in embryo survival throughout gestation. The associated SNP can be used for marker-assisted selection in the studied populations, and further studies of the HBEGF gene are warranted to investigate its role in GLE. © 2015 Stichting International Foundation for Animal Genetics.

Familial risk of epilepsy: a population-based study

PubMed Central

Peljto, Anna L.; Barker-Cummings, Christie; Vasoli, Vincent M.; Leibson, Cynthia L.; Hauser, W. Allen; Buchhalter, Jeffrey R.

2014-01-01

Almost all previous studies of familial risk of epilepsy have had potentially serious methodological limitations. Our goal was to address these limitations and provide more rigorous estimates of familial risk in a population-based study. We used the unique resources of the Rochester Epidemiology Project to identify all 660 Rochester, Minnesota residents born in 1920 or later with incidence of epilepsy from 1935–94 (probands) and their 2439 first-degree relatives who resided in Olmsted County. We assessed incidence of epilepsy in relatives by comprehensive review of the relatives’ medical records, and estimated age-specific cumulative incidence and standardized incidence ratios for epilepsy in relatives compared with the general population, according to proband and relative characteristics. Among relatives of all probands, cumulative incidence of epilepsy to age 40 was 4.7%, and risk was increased 3.3-fold (95% confidence interval 2.75–5.99) compared with population incidence. Risk was increased to the greatest extent in relatives of probands with idiopathic generalized epilepsies (standardized incidence ratio 6.0) and epilepsies associated with intellectual or motor disability presumed present from birth, which we denoted ‘prenatal/developmental cause’ (standardized incidence ratio 4.3). Among relatives of probands with epilepsy without identified cause (including epilepsies classified as ‘idiopathic’ or ‘unknown cause’), risk was significantly increased for epilepsy of prenatal/developmental cause (standardized incidence ratio 4.1). Similarly, among relatives of probands with prenatal/developmental cause, risk was significantly increased for epilepsies without identified cause (standardized incidence ratio 3.8). In relatives of probands with generalized epilepsy, standardized incidence ratios were 8.3 (95% confidence interval 2.93–15.31) for generalized epilepsy and 2.5 (95% confidence interval 0.92–4.00) for focal epilepsy. In relatives of

Prevalence and demographic determinants of gastroesophageal reflux disease (GERD) in the Turkish general population: a population-based cross-sectional study.

PubMed

Mungan, Zeynel

2012-08-01

We aimed to establish the prevalence and demographic determinants of gastroesophageal reflux disease in the Turkish general population using the Turkish version of the gastroesophageal reflux disease questionnaire. A total of 8143 volunteers (mean age: 38.5 (13.3) years; 52.3% males) were included in this cross-sectional questionnaire study conducted via face-to-face administration of the questionnaire forms including items on sociodemographic features, past history of gastric disorders, gastroesophageal reflux disease, the influence of reflux symptoms on patients' lives, physician visits, diagnostic tests, and reflux medications. A past history of gastric symptoms was reported in half of the population. More female participants (p<0.001) had a past history of gastric symptoms that yielded a previous diagnosis of gastroesophageal reflux disease in 19.1% of the population. The likelihood of gastroesophageal reflux disease was low in the majority (75.3%) of the subjects evaluated. Gastroesophageal reflux disease with an inconveniencing or disrupting impact on the patient's life was present in 17.9% and 6.8% of the population. Total gastroesophageal reflux disease-questionnaire scores and reflux prevalence were higher in older age groups (p<0.001). Females were more likely to have gastroesophageal reflux disease prevalence based on reflux symptoms. The impact of gastroesophageal reflux disease on sleep and psychological/emotional well-being was more pronounced in older and female patients, whereas the impact on eating/drinking behaviors and physical-social activities was more marked among females independent of their age (p<0.001). Reflux prevalence was higher in subjects from East Anatolia, Central Anatolia, Mediterranean, and Black Sea regions of Turkey (p<0.001 for each). Prevalence and demographic determinants of gastroesophageal reflux disease are compatible with the profile of the disease in the other Western populations, with a predilection for females and

Study design and sampling intensity for demographic analyses of bear populations

USGS Publications Warehouse

Harris, R.B.; Schwartz, C.C.; Mace, R.D.; Haroldson, M.A.

2011-01-01

The rate of population change through time (??) is a fundamental element of a wildlife population's conservation status, yet estimating it with acceptable precision for bears is difficult. For studies that follow known (usually marked) bears, ?? can be estimated during some defined time by applying either life-table or matrix projection methods to estimates of individual vital rates. Usually however, confidence intervals surrounding the estimate are broader than one would like. Using an estimator suggested by Doak et al. (2005), we explored the precision to be expected in ?? from demographic analyses of typical grizzly (Ursus arctos) and American black (U. americanus) bear data sets. We also evaluated some trade-offs among vital rates in sampling strategies. Confidence intervals around ?? were more sensitive to adding to the duration of a short (e.g., 3 yrs) than a long (e.g., 10 yrs) study, and more sensitive to adding additional bears to studies with small (e.g., 10 adult females/yr) than large (e.g., 30 adult females/yr) sample sizes. Confidence intervals of ?? projected using process-only variance of vital rates were only slightly smaller than those projected using total variances of vital rates. Under sampling constraints typical of most bear studies, it may be more efficient to invest additional resources into monitoring recruitment and juvenile survival rates of females already a part of the study, than to simply increase the sample size of study females. ?? 2011 International Association for Bear Research and Management.

European Population Substructure: Clustering of Northern and Southern Populations

PubMed Central

Seldin, Michael F; Shigeta, Russell; Villoslada, Pablo; Selmi, Carlo; Tuomilehto, Jaakko; Silva, Gabriel; Belmont, John W; Klareskog, Lars; Gregersen, Peter K

2006-01-01

Using a genome-wide single nucleotide polymorphism (SNP) panel, we observed population structure in a diverse group of Europeans and European Americans. Under a variety of conditions and tests, there is a consistent and reproducible distinction between “northern” and “southern” European population groups: most individual participants with southern European ancestry (Italian, Spanish, Portuguese, and Greek) have >85% membership in the “southern” population; and most northern, western, eastern, and central Europeans have >90% in the “northern” population group. Ashkenazi Jewish as well as Sephardic Jewish origin also showed >85% membership in the “southern” population, consistent with a later Mediterranean origin of these ethnic groups. Based on this work, we have developed a core set of informative SNP markers that can control for this partition in European population structure in a variety of clinical and genetic studies. PMID:17044734

Asthma exacerbation and proximity of residence to major roads: a population-based matched case-control study among the pediatric Medicaid population in Detroit, Michigan

PubMed Central

2011-01-01

Background The relationship between asthma and traffic-related pollutants has received considerable attention. The use of individual-level exposure measures, such as residence location or proximity to emission sources, may avoid ecological biases. Method This study focused on the pediatric Medicaid population in Detroit, MI, a high-risk population for asthma-related events. A population-based matched case-control analysis was used to investigate associations between acute asthma outcomes and proximity of residence to major roads, including freeways. Asthma cases were identified as all children who made at least one asthma claim, including inpatient and emergency department visits, during the three-year study period, 2004-06. Individually matched controls were randomly selected from the rest of the Medicaid population on the basis of non-respiratory related illness. We used conditional logistic regression with distance as both categorical and continuous variables, and examined non-linear relationships with distance using polynomial splines. The conditional logistic regression models were then extended by considering multiple asthma states (based on the frequency of acute asthma outcomes) using polychotomous conditional logistic regression. Results Asthma events were associated with proximity to primary roads with an odds ratio of 0.97 (95% CI: 0.94, 0.99) for a 1 km increase in distance using conditional logistic regression, implying that asthma events are less likely as the distance between the residence and a primary road increases. Similar relationships and effect sizes were found using polychotomous conditional logistic regression. Another plausible exposure metric, a reduced form response surface model that represents atmospheric dispersion of pollutants from roads, was not associated under that exposure model. Conclusions There is moderately strong evidence of elevated risk of asthma close to major roads based on the results obtained in this population

Population Growth and Economic Development: Lessons from Selected Asian Countries. Policy Development Studies, Number 10.

ERIC Educational Resources Information Center

Mason, Andrew; And Others

The major findings of a research project on the relationship between population growth and economic development are summarized in this monograph. The study compares recent demographic and economic trends in Japan, Korea, Thailand, and Indonesia to worldwide experience as described by an econometric model of population and development. The study…

Estimating population size in wastewater-based epidemiology. Valencia metropolitan area as a case study.

PubMed

Rico, María; Andrés-Costa, María Jesús; Picó, Yolanda

2017-02-05

Wastewater can provide a wealth of epidemiologic data on common drugs consumed and on health and nutritional problems based on the biomarkers excreted into community sewage systems. One of the biggest uncertainties of these studies is the estimation of the number of inhabitants served by the treatment plants. Twelve human urine biomarkers -5-hydroxyindoleacetic acid (5-HIAA), acesulfame, atenolol, caffeine, carbamazepine, codeine, cotinine, creatinine, hydrochlorothiazide (HCTZ), naproxen, salicylic acid (SA) and hydroxycotinine (OHCOT)- were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) to estimate population size. The results reveal that populations calculated from cotinine, 5-HIAA and caffeine are commonly in agreement with those calculated by the hydrochemical parameters. Creatinine is too unstable to be applicable. HCTZ, naproxen, codeine, OHCOT and carbamazepine, under or overestimate the population compared to the hydrochemical population estimates but showed constant results through the weekdays. The consumption of cannabis, cocaine, heroin and bufotenine in Valencia was estimated for a week using different population calculations. Copyright © 2016 Elsevier B.V. All rights reserved.

The population-based Barcelona-Asymptomatic Intracranial Atherosclerosis Study (ASIA): rationale and design

PubMed Central

2011-01-01

Background Large-artery intracranial atherosclerosis may be the most frequent cause of ischemic stroke worldwide. Traditional approaches have attempted to target the disease when it is already symptomatic. However, early detection of intracranial atherosclerosis may allow therapeutic intervention while the disease is still asymptomatic. The prevalence and natural history of asymptomatic intracranial atherosclerosis in Caucasians remain unclear. The aims of the Barcelona-ASymptomatic Intracranial Atherosclerosis (ASIA) study are (1) to determine the prevalence of ASIA in a moderate-high vascular risk population, (2) to study its prognostic impact on the risk of suffering future major ischemic events, and (3) to identify predictors of the development, progression and clinical expression of this condition. Methods/Design Cross-over and cohort, population-based study. A randomly selected representative sample of 1,503 subjects with a mild-moderate-high vascular risk (as defined by a REGICOR score ≥ 5%) and with neither a history of cerebrovascular nor ischemic heart disease will be studied. At baseline, all individuals will undergo extracranial and transcranial Color-Coded Duplex (TCCD) ultrasound examinations to detect presence and severity of extra and intracranial atherosclerosis. Intracranial stenoses will be assessed by magnetic resonance angiography (MRA). Clinical and demographic variables will be recorded and blood samples will be drawn to investigate clinical, biological and genetic factors associated with the presence of ASIA. A long-term clinical and sonographic follow-up will be conducted thereafter to identify predictors of disease progression and of incident vascular events. Discussion The Barcelona-ASIA is a population-based study aiming to evaluate the prevalence and clinical importance of asymptomatic intracranial large-artery atherosclerosis in Caucasians. The ASIA project may provide a unique scientific resource to better understand the dynamics of

The population-based Barcelona-Asymptomatic Intracranial Atherosclerosis Study (ASIA): rationale and design.

PubMed

López-Cancio, Elena; Dorado, Laura; Millán, Mónica; Reverté, Silvia; Suñol, Anna; Massuet, Anna; Mataró, María; Galán, Amparo; Alzamora, Maite; Pera, Guillem; Torán, Pere; Dávalos, Antoni; Arenillas, Juan F

2011-02-17

Large-artery intracranial atherosclerosis may be the most frequent cause of ischemic stroke worldwide. Traditional approaches have attempted to target the disease when it is already symptomatic. However, early detection of intracranial atherosclerosis may allow therapeutic intervention while the disease is still asymptomatic. The prevalence and natural history of asymptomatic intracranial atherosclerosis in Caucasians remain unclear. The aims of the Barcelona-ASymptomatic Intracranial Atherosclerosis (ASIA) study are (1) to determine the prevalence of ASIA in a moderate-high vascular risk population, (2) to study its prognostic impact on the risk of suffering future major ischemic events, and (3) to identify predictors of the development, progression and clinical expression of this condition. Cross-over and cohort, population-based study. A randomly selected representative sample of 1,503 subjects with a mild-moderate-high vascular risk (as defined by a REGICOR score ≥ 5%) and with neither a history of cerebrovascular nor ischemic heart disease will be studied. At baseline, all individuals will undergo extracranial and transcranial Color-Coded Duplex (TCCD) ultrasound examinations to detect presence and severity of extra and intracranial atherosclerosis. Intracranial stenoses will be assessed by magnetic resonance angiography (MRA). Clinical and demographic variables will be recorded and blood samples will be drawn to investigate clinical, biological and genetic factors associated with the presence of ASIA. A long-term clinical and sonographic follow-up will be conducted thereafter to identify predictors of disease progression and of incident vascular events. The Barcelona-ASIA is a population-based study aiming to evaluate the prevalence and clinical importance of asymptomatic intracranial large-artery atherosclerosis in Caucasians. The ASIA project may provide a unique scientific resource to better understand the dynamics of intracranial atherosclerosis from

Cancer incidence among population utilizing geothermal hot water: a census-based cohort study.

PubMed

Kristbjornsdottir, Adalbjorg; Rafnsson, Vilhjalmur

2013-12-15

The aim of the study was to assess whether utilization of geothermal hot-water is associated with risk of cancer. The cohort from census was followed from 1981 to 2010 in nation-wide death and cancer registries. The moving apart of American-Eurasian tectonic plates, observed in Iceland, results in high volcanic activity. The definition of the study populations was based on geological information. The target population was inhabitants of communities located on bedrock younger than 3.3 million years, utilizing hot-water supply generated from geothermal wells since 1972. The two reference populations were inhabitants of communities without this hot-water supply located on areas with less volcanic/geothermal activity, and bedrock older than 3.3 million years. Hazard ratio (HR), and 95% confidence intervals (CI) were adjusted for age, gender, education, housing, reproductive factors and smoking. HR in the geothermal hot-water supply areas for all cancer was 1.15 (95% CI 1.05-1.25) as compared with nongeothermal areas. The HR for breast cancer was 1.40 (1.12-1.75), prostate cancer 1.61 (1.29-2.00), kidney cancer 1.64 (1.11-2.41), lymphatic and haematopoietic tissue cancers 1.45 (1.08-1.95), and for basal cell carcinoma (BCC) of the skin 1.46 (1.16-1.82). Positive exposure-response relations were observed between the risk of these cancers and the degree of volcanic/geothermal activity in the reference areas. Increased incidence of all cancers, breast, prostate, kidney cancer and BCC of the skin was found among the population utilizing geothermal hot-water for decades. More precise information on exposure is needed in future studies. Copyright © 2013 UICC.

Cardiovascular risk factors in a Mexican middle-class urban population. The Lindavista Study. Baseline data.

PubMed

Meaney, Alejandra; Ceballos-Reyes, Guillermo; Gutiérrez-Salmean, Gabriela; Samaniego-Méndez, Virginia; Vela-Huerta, Agustín; Alcocer, Luis; Zárate-Chavarría, Elisa; Mendoza-Castelán, Emma; Olivares-Corichi, Ivonne; García-Sánchez, Rubén; Martínez-Marroquín, Yolanda; Ramírez-Sánchez, Israel; Meaney, Eduardo

2013-01-01

The aim of this communication is to describe the cardiovascular risk factors affecting a Mexican urban middle-class population. A convenience sample of 2602 middle class urban subjects composed the cohort of the Lindavista Study, a prospective study aimed to determine if conventional cardiovascular risks factors have the same prognosis impact as in other populations. For the baseline data, several measurements were done: obesity indexes, smoking, blood pressure, fasting serum glucose, total cholesterol, HDL-c, LDL-c and triglycerides. This paper presents the basal values of this population, which represents a sample of the Mexican growing urban middle-class. The mean age in the sample was 50 years; 59% were females. Around 50% of the entire group were overweighed, while around 24% were obese. 32% smoked; 32% were hypertensive with a 20% rate of controlled pressure. 6% had diabetes, and 14% had impaired fasting glucose; 66% had total cholesterol ≥ 200 mg/dL; 62% showed HDL-c levels<40 mg/dL; 52% triglycerides>150 mg/dL, and 34% levels of LDL-c ≥ 160 mg/dL. Half of the population studied had the metabolic syndrome. These data show a population with a high-risk profile, secondary to the agglomeration of several cardiovascular risk factors. Copyright © 2012 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.

Size matters: How population size influences genotype–phenotype association studies in anonymized data

PubMed Central

Denny, Joshua C.; Haines, Jonathan L.; Roden, Dan M.; Malin, Bradley A.

2014-01-01

Objective Electronic medical records (EMRs) data is increasingly incorporated into genome-phenome association studies. Investigators hope to share data, but there are concerns it may be “re-identified” through the exploitation of various features, such as combinations of standardized clinical codes. Formal anonymization algorithms (e.g., k-anonymization) can prevent such violations, but prior studies suggest that the size of the population available for anonymization may influence the utility of the resulting data. We systematically investigate this issue using a large-scale biorepository and EMR system through which we evaluate the ability of researchers to learn from anonymized data for genome- phenome association studies under various conditions. Methods We use a k-anonymization strategy to simulate a data protection process (on data sets containing clinical codes) for resources of similar size to those found at nine academic medical institutions within the United States. Following the protection process, we replicate an existing genome-phenome association study and compare the discoveries using the protected data and the original data through the correlation (r2) of the p-values of association significance. Results Our investigation shows that anonymizing an entire dataset with respect to the population from which it is derived yields significantly more utility than small study-specific datasets anonymized unto themselves. When evaluated using the correlation of genome-phenome association strengths on anonymized data versus original data, all nine simulated sites, results from largest-scale anonymizations (population ∼ 100;000) retained better utility to those on smaller sizes (population ∼ 6000—75;000). We observed a general trend of increasing r2 for larger data set sizes: r2 = 0.9481 for small-sized datasets, r2 = 0.9493 for moderately-sized datasets, r2 = 0.9934 for large-sized datasets. Conclusions This research implies that regardless of the

The risk-stratified osteoporosis strategy evaluation study (ROSE): a randomized prospective population-based study. Design and baseline characteristics.

PubMed

Rubin, Katrine Hass; Holmberg, Teresa; Rothmann, Mette Juel; Høiberg, Mikkel; Barkmann, Reinhard; Gram, Jeppe; Hermann, Anne Pernille; Bech, Mickael; Rasmussen, Ole; Glüer, Claus C; Brixen, Kim

2015-02-01

The risk-stratified osteoporosis strategy evaluation study (ROSE) is a randomized prospective population-based study investigating the effectiveness of a two-step screening program for osteoporosis in women. This paper reports the study design and baseline characteristics of the study population. 35,000 women aged 65-80 years were selected at random from the population in the Region of Southern Denmark and-before inclusion-randomized to either a screening group or a control group. As first step, a self-administered questionnaire regarding risk factors for osteoporosis based on FRAX(®) was issued to both groups. As second step, subjects in the screening group with a 10-year probability of major osteoporotic fractures ≥15% were offered a DXA scan. Patients diagnosed with osteoporosis from the DXA scan were advised to see their GP and discuss pharmaceutical treatment according to Danish National guidelines. The primary outcome is incident clinical fractures as evaluated through annual follow-up using the Danish National Patient Registry. The secondary outcomes are cost-effectiveness, participation rate, and patient preferences. 20,904 (60%) women participated and included in the baseline analyses (10,411 in screening and 10,949 in control group). The mean age was 71 years. As expected by randomization, the screening and control groups had similar baseline characteristics. Screening for osteoporosis is at present not evidence based according to the WHO screening criteria. The ROSE study is expected to provide knowledge of the effectiveness of a screening strategy that may be implemented in health care systems to prevent fractures.

Determinants of neonatal mortality in rural Haryana: a retrospective population based study.

PubMed

Upadhyay, R P; Dwivedi, P R; Rai, S K; Misra, P; Kalaivani, M; Krishnan, A

2012-04-01

To identify the determinants of neonatal mortality. Nested case-control study. 28 villages under the intensive field practice area of Comprehensive Rural Health Services Project, Ballabgarh, Haryana serving a population of 87,016, as on 31st December 2009. The study period was from 2005 to 2009. The data were obtained from Health Management Information System and analyzed using multivariate logistic regression analysis. A hierarchical approach was used to analyze the factors associated with neonatal deaths, using community level factors, socio-economic status and biological determinants. The population attributable fractions were estimated for significant variables. The total live births during the study period were 10392 and neonatal deaths were 248. The infant and neonatal mortality rates during the study period were 45.6 and 23.8 per 1000 live births, respectively. Socio-economic determinants (Low educational status of parents [OR 2.1, 95% CI; 1.4, 3.3]; fathers occupation [OR 1.8, 95% CI; 1.0, 3.0]; Rajput caste [OR 2.0, 95% CI; 1.2, 3.4] appeared to explain a major fraction (45.7%) of neonatal deaths. Community level factors (villages with no health facility [OR 1.5, 95% CI; 1.0, 2.1]; villages with population >6000 [OR 1.7, 95% CI; 1.2, 2.5]) were associated with 27.3% of all neonatal deaths. Proximate determinants (early childbearing age of mother (<20 years) [OR 2.0, 95% CI; 1.2, 3.2]) were least important. All the three level of variables seemed to act independently with little mediation among them. Neonatal mortality is affected by socioeconomic, community level and proximate biological determinants.

Adverse life events and health: a population study in Hong Kong.

PubMed

Karatzias, Thanos; Yan, Elsie; Jowett, Sally

2015-02-01

Although the effects of adverse life events on mental health have been well documented in the literature, there has never been a population based study that investigated systematically the association between history of adverse life events and physical health (objective and subjective) in adults. Cross-sectional, face-to-face household population based survey of adults (18+) in Hong Kong (N=1147). Participants were asked if they had a diagnosis of six health conditions including hypertension, heart disease, arthritis, diabetes, eyesight degeneration, and hearing loss. They were also asked if they had experienced five adverse life events including death of a partner or spouse, abuse, natural disaster, life threatening illness or injury, and family disruption. Interviews also included the Short-Form 12 Health Survey (SFHS-12) and the short version of the Centre for Epidemiologic Studies Depression Scale (CES-D). Overall, results indicate that specific adverse life events may be associated with specific health conditions. However, all tested life events were associated with subjective physical and mental health. Death of partner or parent and life threatening illness or injury were found to have the strongest association with physical health problems. A dose-response relationship between adverse life events and physical health in general was evident but more so for heart disease and eyesight degeneration. Considering the high prevalence of traumatic events and how common the conditions associated with such events are in the general population, screening for adverse life events as part of comprehensive assessment will allow a deeper understanding of patients' needs. Copyright © 2014 Elsevier Inc. All rights reserved.

Association between salt and hypertension in rural and urban populations of low to middle income countries: a systematic review and meta-analysis of population based studies.

PubMed

Subasinghe, Asvini K; Arabshahi, Simin; Busingye, Doreen; Evans, Roger G; Walker, Karen Z; Riddell, Michaela A; Thrift, Amanda G

2016-01-01

The prevalence of hypertension, the greatest contributor to mortality globally, is increasing in low-and-middle income countries (LMICs). In urban regions of LMICs, excessive salt intake is associated with increased risk of hypertension. We aimed to determine whether this is the case in rural regions as well. We performed a meta-analysis of studies in rural and urban areas of LMICs in which the association of salt and hypertension were assessed using multivariable models. We identified 18 studies with a total of 134,916 participants. The prevalence of high salt intake ranged from 21.3% to 89.5% in rural and urban populations. When salt was analysed as a continuous variable, a greater impact of salt on hypertension was found in urban (n=4) (pooled effect size (ES) 1.42, 95% CI 1.19, 1.69) than in rural populations (n=4) (pooled ES 1.07, 95% CI 1.04, 1.10, p for difference <0.001). In studies where salt was analysed continuously, a greater impact of salt on hypertension was observed in lean rural populations (BMI <23 kg/m2) than in non-lean rural populations (BMI >=23 kg/m2, p for difference <0.001). The prevalence of high salt intake is similar in rural and urban regions. Excessive salt intake has a greater impact on the prevalence of hypertension in urban than rural regions. BMI appears to modify the relationship between salt and hypertension in rural populations.

Population Pharmacokinetic Model of Doxycycline Plasma Concentrations Using Pooled Study Data.

PubMed

Hopkins, Ashley M; Wojciechowski, Jessica; Abuhelwa, Ahmad Y; Mudge, Stuart; Upton, Richard N; Foster, David J R

2017-03-01

The literature presently lacks a population pharmacokinetic analysis of doxycycline. This study aimed to develop a population pharmacokinetic model of doxycycline plasma concentrations that could be used to assess the power of bioequivalence between Doryx delayed-release tablets and Doryx MPC. Doxycycline pharmacokinetic data were available from eight phase 1 clinical trials following single/multiple doses of conventional-release doxycycline capsules, Doryx delayed-release tablets, and Doryx MPC under fed and fasted conditions. A population pharmacokinetic model was developed in a stepwise manner using NONMEM, version 7.3. The final covariate model was developed according to a forward inclusion ( P < 0.01) and then backward deletion ( P < 0.001) procedure. The final model was a two-compartment model with two-transit absorption compartments. Structural covariates in the base model included formulation effects on relative bioavailability ( F ), absorption lag (ALAG), and the transit absorption rate (KTR) under the fed status. An absorption delay (lag) for the fed status (FTLAG2 = 0.203 h) was also included in the model as a structural covariate. The fed status was observed to decrease F by 10.5%, and the effect of female sex was a 14.4% increase in clearance. The manuscript presents the first population pharmacokinetic model of doxycycline plasma concentrations following oral doxycycline administration. The model was used to assess the power of bioequivalence between Doryx delayed-release tablets and Doryx MPC, and it could potentially be used to critically examine and optimize doxycycline dose regimens. Copyright © 2017 American Society for Microbiology.

Immigrants’ duration of residence and adverse birth outcomes: a population-based study

PubMed Central

Urquia, ML; Frank, JW; Moineddin, R; Glazier, RH

2010-01-01

Please cite this paper as: Urquia M, Frank J, Moineddin R, Glazier R. Immigrants’ duration of residence and adverse birth outcomes: a population-based study. BJOG 2010;117:591–601. Objective This study aimed to examine preterm and small-for-gestational-age (SGA) births among immigrants, by duration of residence, and to compare them with the Canadian-born population. Design Population-based cross-sectional study with retrospective assessment of immigration. Setting Metropolitan areas of Ontario, Canada. Population A total of 83 233 singleton newborns born to immigrant mothers and 314 237 newborns born to non-immigrant mothers. Methods We linked a database of immigrants acquiring permanent residence in Ontario, Canada, in the period 1985–2000 with mother–infant hospital records (2002–2007). Duration of residence was measured as completed years from arrival to Canada to delivery/birth. Logistic regression models were used to estimate the effects of duration of residence with adjusted odds ratios and 95% confidence intervals. In analyses restricted to immigrants only, hierarchical models were used to account for the clustering of births into maternal countries of birth. Main outcome measures Preterm birth (PTB) and SGA birth. Results Recent immigrants (<5 years) had a lower risk of PTB (4.7%) than non-immigrants (6.2%), but those with ≥15 years of stay were at higher risk (7.4%). Among immigrants, a 5-year increase in Canadian residence was associated with an increase in PTB (AOR 1.14, 95% CI 1.10–1.19), but not in SGA birth (AOR 0.99, 95% CI 0.96–1.02). Conclusions Time since migration was associated with increases in the risk of PTB, but was not associated with an increase in SGA births. Ignoring duration of residence may mask important disparities in preterm delivery between immigrants and non-immigrants, and between immigrant subgroups categorised by their duration of residence. PMID:20374596

An epidemiologic study of tinnitus in a population in Jiangsu Province, China.

PubMed

Xu, Xia; Bu, Xingkuan; Zhou, Ling; Xing, Guangqian; Liu, Cheng; Wang, Dengyuan

2011-10-01

Tinnitus is a common complaint and often of no clinical significance. There are a number of unresolved issues concerning the etiology, pathogenesis, and natural history of tinnitus. There are a few current population-based estimates of the prevalence of tinnitus done in representative large geographic areas, but there is little data from multi-area, large sample studies of tinnitus in China. To investigate the prevalence of tinnitus and related factors in a Chinese population. These data would be used to plan and evaluate health-care services. We carried out an epidemiologic study of tinnitus as part of an epidemiologic study of ear and hearing disorders that was undertaken in Jiangsu Province, China. A question about tinnitus history was included in a comprehensive questionnaire about hearing. All participants also had both pure tone audiometry and an otological examination. The sample consisted of 6333 people 10 yr of age or older, selected by the methods of probability proportional to size. All participants answered a questionnaire concerning their tinnitus and had pure tone audiometry testing and an ear examination. All data were entered using EPIDATD 3.0 software and analyzed by a chi-squared test and test for trends. The overall prevalence of tinnitus was 14.5%, and the standardized rates were 11.4% in the whole country and 12.4% in Jiangsu province. Its prevalence increased with age. The prevalence of tinnitus was 11.9 and 15.6% in urban and rural residents, respectively There was no significant difference in prevalence between men and women. Hearing impairment, history of middle ear infections, and noise exposure were the main risk factors for tinnitus. Tinnitus is a common problem in the population. With the aging of the population, the prevalence of tinnitus will increase. The prevention of tinnitus should focus on hearing impairment screening, otitis media treatment, and noise exposure reduction. Health services in rural areas should emphasize prevention

Suicidal Decapitation by Hanging-A Population-based Study.

PubMed

Byard, Roger W; Gilbert, John D

2018-05-01

A prospective study was undertaken at Forensic Science SA over a 15-year period from July 2002 to June 2017 for all cases of adult (>18 years) suicidal hangings with decapitation. A total of 1446 cases of suicidal hangings were identified from a general population of approximately 1.5 million (1206 males-age range 18-97 years, average 42.6; and 240 females-age range 18-96 years, average 40.1). Only three cases of decapitation were found, all from long-drop hangings; these consisted of three males (ages 32-55 years; average 45 years). Spinal transections had occurred between the first and second, second and third, and third and fourth cervical vertebrae, respectively. In this study, the number of suicidal hangings with decapitation represented only 0.2% of the total number of hangings. These events are therefore extremely rare, most likely due to most suicidal hangings occurring from relatively low levels in a domestic environment. © 2017 American Academy of Forensic Sciences.

Falls among the elderly: risk factors in a population-based study.

PubMed

Rodrigues, Iara Guimarães; Fraga, Gustavo Pereira; Barros, Marilisa Berti de Azevedo

2014-01-01

The aim of the present study was to identify factors associated with the occurrence of falls among elderly adults in a population-based study (ISACamp 2008). A population-based cross-sectional study was carried out with two-stage cluster sampling. The sample was composed of 1,520 elderly adults living in the urban area of the city of Campinas, São Paulo, Brazil. The occurrence of falls was analyzed based on reports of the main accident occurred in the previous 12 months. Data on socioeconomic/demographic factors and adverse health conditions were tested for possible associations with the outcome. Prevalence ratios (PR) were estimated and adjusted for gender and age using the Poisson multiple regression analysis. Falls were more frequent, after adjustment for gender and age, among female elderly participants (PR = 2.39; 95% confidence interval (95% CI) 1.47 - 3.87), elderly adults (80 years old and older) (PR = 2.50; 95% CI 1.61 - 3.88), widowed (PR = 1.74; 95% CI 1.04 - 2.89) and among elderly adults who had rheumatism/arthritis/arthrosis (PR = 1.58; 95% CI 1.00 - 2.48), osteoporosis (PR = 1.71; 95% CI 1.18 - 2.49), asthma/bronchitis/emphysema (PR = 1,73; 95% CI 1.09 - 2.74), headache (PR = 1.59; 95% CI 1.07 - 2.38), mental common disorder (PR = 1.72; 95% CI 1.12 - 2.64), dizziness (PR = 2.82; 95% CI 1.98 - 4.02), insomnia (PR = 1.75; 95% CI 1.16 - 2.65), use of multiple medications (five or more) (PR = 2.50; 95% CI 1.12 - 5.56) and use of cane/walker (PR = 2.16; 95% CI 1.19 - 3,93). The present study shows segments of the elderly population who are more prone to falls through the identification of factors associated with this outcome. The findings can contribute to the planning of public health policies and programs addressed to the prevention of falls.

Ethnicity and sepsis characteristics and outcomes. Population based study.

PubMed

Karp, Galia; Perl, Yael; Fuchs, Lior; Almog, Yaniv; Klein, Moti; Vodonos, Alina; Dreiher, Jacob; Talmor, Daniel; Codish, Shlomi; Novack, Victor

2013-01-01

Two distinct ethnic groups live in Southern Israel: urban Jews and rural Bedouin Arabs. These groups differ in their socioeconomic status, culture and living environment, and are treated in a single regional tertiary care hospital. We hypothesized that these two ethnic groups have different patterns of sepsis-related intensive care admissions. The study included all adult patients admitted to the Soroka University Medical Center Intensive Care Units between January 2002 and December 2008, with a diagnosis of sepsis. Demographic data, medical history, and hospitalization and outcomes data were obtained. Primary outcome was all-cause mortality. Jewish patients admitted to the ICU (1343, 87%) were on average 17 years older than Bedouin Arabs (199, 13%). For the population <65 years, Bedouin Arabs had slightly higher age-adjusted prevalence of ICU sepsis admissions than Jewish patients (39.5 vs. 43.0, p=0.25), while for the population >65 years there was a reverse trend (21.8 vs. 19.8 p=0.49). There were no differences in the type of organ failure, sepsis severity or length of hospitalization between the two groups. Twenty eight days/in-hospital mortality was 33.9% in Bedouin Arabs vs. 45.5% in Jews, p=0.004. Following adjustment for comorbidities, age and severity of the disease, survival was unrelated to ethnicity, both at 28 days (odds ratio for Bedouin Arabs 0.86, 95% CI 0.66-1.24) and following hospital discharge (hazard ratio 0.86, 95% 0.67-1.09). Sepsis-related ICU admissions are more prevalent among Bedouin Arabs at younger age compared with the Jewish population. Adjusted for confounders, ethnicity does not influence prognosis. Copyright © 2012 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

Prevalence and Pattern of Mandibular Third Molar Impaction in Eritrean Population: A Retrospective Study.

PubMed

Kumar, V Raj; Yadav, Priya; Kahsu, Efrem; Girkar, Farhana; Chakraborty, Rajnish

2017-02-01

The most commonly impacted tooth in the oral cavity is the mandibular third molar. Various etiologic factors have been suggested for impacted mandibular third molars. The pattern and prevalence of impacted mandibular third molars vary with different population and region. This study throws light on the prevalence and pattern of impacted mandibular third molars in Eritrea, East Africa. This is the first reported study regarding the same from Eritrea. To assess the prevalence and pattern of impacted mandibu-lar third molars in the population of Eritrea, East Africa by conducting a retrospective study from January 2009 to January 2014. This study was conducted in the Department of Oral and Maxillofacial Surgery, Orotta School of Medicine and Dental Medicine and the Orotta Referral Medical and Surgical Hospital, Asmara, Eritrea. A total of 1,813 clinical and radiographic records [orthopantomograms] were assessed and 276 cases were selected for the study as per the inclusion criteria. They were evaluated for the frequency among the various age groups, gender and region along with the sides affected, angulation and level of impaction. The presence of systemic conditions and associated pathologies was also assessed according to the type of impaction. The average age of these patients in the study was found to be 30 years, with the 20 to 30 years age group being the most affected (67.4%). Females (53.3%) were affected more than the males (46.7%). People from the Asmara region showed significantly more prevalence (79.7%) than the adjoining areas (20.3%). Mesioangular impaction was the most common angulation with a definite relationship to the age groups (p = 0.032). The level of impaction had no significant relationship to the age groups, gender, or region, although class I position A was found to be the most common type. Mesioangular class I position A impac-tion showed an apparent relationship with underlying systemic conditions, but it was statistically insignificant

Survival-related Selection Bias in Studies of Racial Health Disparities: The Importance of the Target Population and Study Design.

PubMed

Howe, Chanelle J; Robinson, Whitney R

2018-07-01

The impact of survival-related selection bias has not always been discussed in relevant studies of racial health disparities. Moreover, the analytic approaches most frequently employed in the epidemiologic literature to minimize selection bias are difficult to implement appropriately in racial disparities research. This difficulty stems from the fact that frequently employed analytic techniques require that common causes of survival and the outcome are accurately measured. Unfortunately, such common causes are often unmeasured or poorly measured in racial health disparities studies. In the absence of accurate measures of the aforementioned common causes, redefining the target population or changing the study design represents a useful approach for reducing the extent of survival-related selection bias. To help researchers recognize and minimize survival-related selection bias in racial health disparities studies, we illustrate the aforementioned selection bias and how redefining the target population or changing the study design can be useful.

Coordination between Education and Population Policies--A Case Study of India.

ERIC Educational Resources Information Center

Chawla, S. P.

Population and educational policies of the government of India since 1950 are reviewed. A major objective of the study is to take stock of accomplishments and problems in the two policy areas so that policymakers will have up to date information upon which to base future planning. The document is presented in seven chapters. Chapter I offers an…

Methods of Suicide among Cancer Patients: A Nationwide Population-Based Study

ERIC Educational Resources Information Center

Chung, Kuo-Hsuan; Lin, Herng-Ching

2010-01-01

A 3-year nationwide population-based data set was used to explore methods of suicide (violent vs. nonviolent) and possible contributing factors among cancer patients in Taiwan. A total of 1,065 cancer inpatients who committed suicide were included as our study sample. The regression shows that those who had genitourinary cancer were 0.55 times (p…

[Study of population profiles in relation to the level of suicide risk in France: Study "Mental health in the general population"].

PubMed

Chabaud, Francis; Debarre, Julie; Serazin, Céline; Bouet, Roland; Vaïva, Guillaume; Roelandt, Jean Luc

2010-01-01

Suicidal behaviour is a very important public health issue. The French study of mental health in the general population casts a whole new insight on this issue thanks to the size of the sample used, to its representative nature and to the variety of the collected data. This study aims at defining better the relationships between the factors of suicide risk within a noninstitutionalized adult population and more specifically between the socioeconomic and the psychopathological factors. The final aim is to help define the intervention strategies which should be developed in the context of prevention programs. The method used consists in estimating the suicide risk for each person included in the study by developing a standardized indicator. Six questions taken from the MINI (Mini International Neuropsychiatric Interview) were used to define the four levels of suicide risks which compose this indicator. Next, this indicator was matched for the socioeconomic variables of the study as well as for the main psychopathological categories. A factor analysis of the numerous relations was then carried out. Its principle consisted in synthesizing the information contained in a great number of variables and individuals thanks to the mathematical projection of these features onto a graph. The variables which were retained for the analysis were those which presented the richest relationship with the main variable.(that is to say the level of suicide risk). The estimated prevalence rate of suicidal risk in the general population (with at least one positive answer) is 13.7% which can be divided into 9.7% of low risk, 2.1% of medium risk and 1.9% of high risk. The relationship between the presence of a psychopathology and a medium or high risk of suicide is quite significant. What is more, the presence of associated pathologies (comorbidities) increases the risk. The highest prevalence of risk is observed in psychotic and depressive disorders. However, suicide risk exists in some

Population Isolation in the Philippine War: A Case Study

DTIC Science & Technology

2015-05-21

concentration camps appear as unnecessary and extremely harsh punishment. In one example of many, extreme charges of hostage taking, rape, and... torture from the Filipinos in Candelaria warranted an Army investigation.13 Secondary sources address environmental effects of population isolation...themselves targeted and potentially killed by the native forces.32 Public displays of these murders and assassinations meant to convince the population to

Population study of hearing disorders in adults: preliminary communication.

PubMed Central

1981-01-01

The Institute of Hearing Research is embarked upon a study of the prevalence, characteristics and determinants of hearing problems and tinnitus in the adult population of the UK. One of its objectives is to ascertain the size of the problem in terms both of numbers of people affected and the degrees to which they are affected. Such knowledge is highly relevant to any consideration of the services needed for the adult hearing impaired. The overall plan for the study and the results of its pilot study are outlined. In Tier A, a questionnaire on hearing difficulties and tinnitus was sent to 6804 persons living in Cardiff, Glasgow, Nottingham and Southampton. This enabled stratification of respondents by age groups and reported impairments, and thereby permitted appropriate sampling ratios from those strata to be invited to attend the clinics for the Tier B clinical and audiological investigations. Response rates were around 80% at Tier A and 50% at Tier B; domiciliary follow up showed the biases in non-responders and non-attenders to be minimal. About 25% of the sample reported some hearing difficulty, and about 17% reported an experience of tinnitus that was more than transitory or temporary noise-induced. Taking a criterion of over 25 dB hearing level in the better ear, averaged across 0.5, 1, 2 and 4 kHz, a prevalence estimate for the UK population is that 19.9 +/- 4.4% of adults are so affected. About 0.5-1% of adults appear to be severely affected by tinnitus; this amounts to about 200 000 persons in the UK. The scale of the problem has not been fully appreciated before and points to an urgent need to develop further the clinical services and research effort in the field of tinnitus. PMID:7299784

"Health divide" between indigenous and non-indigenous populations in Kerala, India: population based study.

PubMed

Haddad, Slim; Mohindra, Katia Sarla; Siekmans, Kendra; Màk, Geneviève; Narayana, Delampady

2012-05-29

The objective of this study is to investigate the magnitude and nature of health inequalities between indigenous (Scheduled Tribes) and non-indigenous populations, as well as between different indigenous groups, in a rural district of Kerala State, India. A health survey was carried out in a rural community (N = 1660 men and women, 18-96 years). Age- and sex-standardised prevalence of underweight (BMI < 18.5 kg/m2), anaemia, goitre, suspected tuberculosis and hypertension was compared across forward castes, other backward classes and tribal populations. Multi-level weighted logistic regression models were used to estimate the predicted prevalence of morbidity for each age and social group. A Blinder-Oaxaca decomposition was used to further explore the health gap between tribes and non-tribes, and between subgroups of tribes. Social stratification remains a strong determinant of health in the progressive social policy environment of Kerala. The tribal groups are bearing a higher burden of underweight (46.1 vs. 24.3%), anaemia (9.9 vs. 3.5%) and goitre (8.5 vs. 3.6%) compared to non-tribes, but have similar levels of tuberculosis (21.4 vs. 20.4%) and hypertension (23.5 vs. 20.1%). Significant health inequalities also exist within tribal populations; the Paniya have higher levels of underweight (54.8 vs. 40.7%) and anaemia (17.2 vs. 5.7%) than other Scheduled Tribes. The social gradient in health is evident in each age group, with the exception of hypertension. The predicted prevalence of underweight is 31 and 13 percentage points higher for Paniya and other Scheduled Tribe members, respectively, compared to Forward Caste members 18-30 y (27.1%). Higher hypertension is only evident among Paniya adults 18-30 y (10 percentage points higher than Forward Caste adults of the same age group (5.4%)). The decomposition analysis shows that poverty and other determinants of health only explain 51% and 42% of the health gap between tribes and non-tribes for

Generalization and dilution of association results from European GWAS in populations of non-European ancestry: the PAGE study.

PubMed

Carlson, Christopher S; Matise, Tara C; North, Kari E; Haiman, Christopher A; Fesinmeyer, Megan D; Buyske, Steven; Schumacher, Fredrick R; Peters, Ulrike; Franceschini, Nora; Ritchie, Marylyn D; Duggan, David J; Spencer, Kylee L; Dumitrescu, Logan; Eaton, Charles B; Thomas, Fridtjof; Young, Alicia; Carty, Cara; Heiss, Gerardo; Le Marchand, Loic; Crawford, Dana C; Hindorff, Lucia A; Kooperberg, Charles L

2013-09-01

The vast majority of genome-wide association study (GWAS) findings reported to date are from populations with European Ancestry (EA), and it is not yet clear how broadly the genetic associations described will generalize to populations of diverse ancestry. The Population Architecture Using Genomics and Epidemiology (PAGE) study is a consortium of multi-ancestry, population-based studies formed with the objective of refining our understanding of the genetic architecture of common traits emerging from GWAS. In the present analysis of five common diseases and traits, including body mass index, type 2 diabetes, and lipid levels, we compare direction and magnitude of effects for GWAS-identified variants in multiple non-EA populations against EA findings. We demonstrate that, in all populations analyzed, a significant majority of GWAS-identified variants have allelic associations in the same direction as in EA, with none showing a statistically significant effect in the opposite direction, after adjustment for multiple testing. However, 25% of tagSNPs identified in EA GWAS have significantly different effect sizes in at least one non-EA population, and these differential effects were most frequent in African Americans where all differential effects were diluted toward the null. We demonstrate that differential LD between tagSNPs and functional variants within populations contributes significantly to dilute effect sizes in this population. Although most variants identified from GWAS in EA populations generalize to all non-EA populations assessed, genetic models derived from GWAS findings in EA may generate spurious results in non-EA populations due to differential effect sizes. Regardless of the origin of the differential effects, caution should be exercised in applying any genetic risk prediction model based on tagSNPs outside of the ancestry group in which it was derived. Models based directly on functional variation may generalize more robustly, but the identification

Generalization and Dilution of Association Results from European GWAS in Populations of Non-European Ancestry: The PAGE Study

PubMed Central

Carlson, Christopher S.; Matise, Tara C.; North, Kari E.; Haiman, Christopher A.; Fesinmeyer, Megan D.; Buyske, Steven; Schumacher, Fredrick R.; Peters, Ulrike; Franceschini, Nora; Ritchie, Marylyn D.; Duggan, David J.; Spencer, Kylee L.; Dumitrescu, Logan; Eaton, Charles B.; Thomas, Fridtjof; Young, Alicia; Carty, Cara; Heiss, Gerardo; Le Marchand, Loic; Crawford, Dana C.; Hindorff, Lucia A.; Kooperberg, Charles L.

2013-01-01

The vast majority of genome-wide association study (GWAS) findings reported to date are from populations with European Ancestry (EA), and it is not yet clear how broadly the genetic associations described will generalize to populations of diverse ancestry. The Population Architecture Using Genomics and Epidemiology (PAGE) study is a consortium of multi-ancestry, population-based studies formed with the objective of refining our understanding of the genetic architecture of common traits emerging from GWAS. In the present analysis of five common diseases and traits, including body mass index, type 2 diabetes, and lipid levels, we compare direction and magnitude of effects for GWAS-identified variants in multiple non-EA populations against EA findings. We demonstrate that, in all populations analyzed, a significant majority of GWAS-identified variants have allelic associations in the same direction as in EA, with none showing a statistically significant effect in the opposite direction, after adjustment for multiple testing. However, 25% of tagSNPs identified in EA GWAS have significantly different effect sizes in at least one non-EA population, and these differential effects were most frequent in African Americans where all differential effects were diluted toward the null. We demonstrate that differential LD between tagSNPs and functional variants within populations contributes significantly to dilute effect sizes in this population. Although most variants identified from GWAS in EA populations generalize to all non-EA populations assessed, genetic models derived from GWAS findings in EA may generate spurious results in non-EA populations due to differential effect sizes. Regardless of the origin of the differential effects, caution should be exercised in applying any genetic risk prediction model based on tagSNPs outside of the ancestry group in which it was derived. Models based directly on functional variation may generalize more robustly, but the identification

Selecting at-risk populations for sexually transmitted disease/HIV intervention studies.

PubMed

Wu, Zunyou; Rotheram-Borus, Mary Jane; Detels, Roger; Li, Li; Guan, Jihui; Liang, Guojun; Yap, Lorraine

2007-12-01

This paper describes one option to select populations for randomized, controlled trials (RCT). We used a popular opinion leader intervention in Fuzhou, China, to: (1) identify population selection criteria; (2) systematically examine the suitability of potential target populations and settings; (3) briefly evaluate risk and stability in the population; and (4) evaluate regional and organizational support among administrators and government officials. After comparing migrant villagers, truck drivers, factory workers, construction workers, and market employees in five regions of China, market employees in Fuzhou were identified as the optimal target population. Markets were the optimal sites for several reasons: (1) the population demonstrated a sufficient base rate of sexually transmitted diseases; (2) the population was stable over time; (3) a sufficient number of sites of manageable sizes were available; (4) stable networks existed; (5) local gatekeepers/stakeholders supported the intervention; (6) there was organizational capacity in the local health department to mount the intervention; (7) the demographic profile was similar across potential sites; and (8) the sites were sufficiently distanced to minimize contamination. Evaluating intervention efficacy in an RCT requires a time-consuming and rigorous process that systematically and routinely documents selection criteria, evaluates multiple populations, sites, and organizations for their appropriateness.

Kidney Disease Among Registered Métis Citizens of Ontario: A Population-Based Cohort Study

PubMed Central

Hayward, Jade S.; McArthur, Eric; Nash, Danielle M.; Sontrop, Jessica M.; Russell, Storm J.; Khan, Saba; Walker, Jennifer D.; Nesrallah, Gihad E.; Sood, Manish M.; Garg, Amit X.

2017-01-01

Background: Indigenous peoples in Canada have higher rates of kidney disease than non-Indigenous Canadians. However, little is known about the risk of kidney disease specifically in the Métis population in Canada. Objective: To compare the prevalence of chronic kidney disease and incidence of acute kidney injury and end-stage kidney disease among registered Métis citizens in Ontario and a matched sample from the general Ontario population. Design: Population-based, retrospective cohort study using data from the Métis Nation of Ontario’s Citizenship Registry and administrative databases. Setting: Ontario, Canada; 2003-2013. Patients: Ontario residents ≥18 years. Measurements: Prevalence of chronic kidney disease and incidence of acute kidney injury and end-stage kidney disease. Secondary outcomes among patients hospitalized with acute kidney injury included non-recovery of kidney function and mortality within 1 year of discharge. Methods: Database codes and laboratory values were used to determine study outcomes. Métis citizens were matched (1:4) to Ontario residents on age, sex, and area of residence. The analysis included 12 229 registered Métis citizens and 48 916 adults from the general population. Results: We found the prevalence of chronic kidney disease was slightly higher among Métis citizens compared with the general population (3.1% vs 2.6%, P = 0.002). The incidence of acute kidney injury was 1.2 per 1000 person-years in both Métis citizens and the general population (P = 0.54). Of those hospitalized with acute kidney injury, outcomes were similar among Métis citizens and the general population except 1-year mortality, which was higher for Métis citizens (24.5% vs 15.3%, P = 0.03). The incidence of end-stage kidney disease did not differ between groups (<3.0 per 10 000 person-years, P = 0.73). Limitations: The Métis Nation of Ontario Citizenship Registry only captures about 20% of Métis people in Ontario. Administrative health care

Emotional development in children with tics: a longitudinal population-based study.

PubMed

Hoekstra, P J; Lundervold, A J; Lie, S A; Gillberg, C; Plessen, Kerstin J

2013-03-01

Children with tics often experience accompanying problems that may have more impact on their well being and quality of life than the tics themselves. The present study investigates characteristics and the course of associated problems. In a population-based follow-up study, we investigated the developmental trajectory of children with and without tics when they were 7-9 years old. Parents and teachers completed the strengths and difficulties questionnaire (SDQ) when the children were 7-9 years (wave 1) and 4 years later (wave 2). Using strict criteria, we identified 38 children with tics in the cohort of 4,025 children (0.94% of the total cohort) with a preponderance of boys (78.9%). 22 children (57.9%) in the group with tics had only motor tics, and 16 (42.1%) had both motor and vocal tics. Children with tics had significantly higher parent- and teacher-rated SDQ total difficulty scores and subscale scores in both waves. Children with tics experienced an increase in emotional problems and in peer problems between the first and the second wave. This study in a general population indicates that the presence of tics is associated with a range of internalizing and externalizing difficulties, as well as problems in peer relationships. Moreover, our study indicates that emotional and peer problems tend to increase over time in the group of children with tics.

Asthma and Attention-Deficit/Hyperactivity Disorder: A Nationwide Population-Based Prospective Cohort Study

ERIC Educational Resources Information Center

Chen, Mu-Hong; Su, Tung-Ping; Chen, Ying-Sheue; Hsu, Ju-Wei; Huang, Kai-Lin; Chang, Wen-Han; Chen, Tzeng-Ji; Bai, Ya-Mei

2013-01-01

Background: Previous cross-sectional studies have suggested an association between asthma and attention-deficit/hyperactivity disorder (ADHD), but the temporal relationship was not determined. Using a nationwide population-based prospective case-control cohort study (1:4, age-/gender-matched), we hypothesized that asthma in infanthood or early…

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.

[Prevalence of lower urinary tract symptoms among male population in Russian Federation: analysis of population study results].

PubMed

Korneyev, I; Alexeeva, T; Al-Shukri, S; Bernikov, A; Erkovich, A; Zhuravlev, V; Kamalov, A; Kogan, M; Pavlov, V; Pushkar, D

2015-04-01

The purpose of the present research is to study the incidence and severity of lower urinary tract symptoms (LUTS) in male population of the Russian Federation and to establish the relationship with the most common diseases. Based on the materials of population survey of 1083 men (mean age - 42,8±14,1 years) held in the Russian Federation in 2011-2012 the relationship between age, weight, height, sexual activity, addictions, co-morbidities and the answers to the questionnaire IPSS with the assessment of quality of life in relation with existing disorders of urination (QoL) was studied in six federal districts. 649 (59.9%) respondents had urinary system disorders (IPSS>0), the mean (±SD) of the sum IPSS questionnaire score was 5,0±7,0. LUTS severity was greater in: older men (τB=0,441; p<0,001); in men who had undergone surgeries of the pelvic organs (τB=0,242; p<0,001); in the presence of coronary artery ischaemic disease (τB=0,242; p<0,001), arterial hypertension (τB=0,255; p<0,001); diabetes mellitus (τB=0,154; p<0,001); obesity (τB=0,148; p<0,001); depression (τB=0,126; p<0,001); and sexual disorders (τB=-0,425; p<0,001). The prevalence of LUTS in men of the Russian Federation is high, their relationship with age and comorbidities require a comprehensive approach to prevention, diagnosis and treatment.

Navigating the currents of seascape genomics: how spatial analyses can augment population genomic studies

PubMed Central

Crandall, Eric D.; Liggins, Libby; Bongaerts, Pim; Treml, Eric A.

2016-01-01

Population genomic approaches are making rapid inroads in the study of non-model organisms, including marine taxa. To date, these marine studies have predominantly focused on rudimentary metrics describing the spatial and environmental context of their study region (e.g., geographical distance, average sea surface temperature, average salinity). We contend that a more nuanced and considered approach to quantifying seascape dynamics and patterns can strengthen population genomic investigations and help identify spatial, temporal, and environmental factors associated with differing selective regimes or demographic histories. Nevertheless, approaches for quantifying marine landscapes are complicated. Characteristic features of the marine environment, including pelagic living in flowing water (experienced by most marine taxa at some point in their life cycle), require a well-designed spatial-temporal sampling strategy and analysis. Many genetic summary statistics used to describe populations may be inappropriate for marine species with large population sizes, large species ranges, stochastic recruitment, and asymmetrical gene flow. Finally, statistical approaches for testing associations between seascapes and population genomic patterns are still maturing with no single approach able to capture all relevant considerations. None of these issues are completely unique to marine systems and therefore similar issues and solutions will be shared for many organisms regardless of habitat. Here, we outline goals and spatial approaches for landscape genomics with an emphasis on marine systems and review the growing empirical literature on seascape genomics. We review established tools and approaches and highlight promising new strategies to overcome select issues including a strategy to spatially optimize sampling. Despite the many challenges, we argue that marine systems may be especially well suited for identifying candidate genomic regions under environmentally mediated

Navigating the currents of seascape genomics: how spatial analyses can augment population genomic studies.

PubMed

Riginos, Cynthia; Crandall, Eric D; Liggins, Libby; Bongaerts, Pim; Treml, Eric A

2016-12-01

Population genomic approaches are making rapid inroads in the study of non-model organisms, including marine taxa. To date, these marine studies have predominantly focused on rudimentary metrics describing the spatial and environmental context of their study region (e.g., geographical distance, average sea surface temperature, average salinity). We contend that a more nuanced and considered approach to quantifying seascape dynamics and patterns can strengthen population genomic investigations and help identify spatial, temporal, and environmental factors associated with differing selective regimes or demographic histories. Nevertheless, approaches for quantifying marine landscapes are complicated. Characteristic features of the marine environment, including pelagic living in flowing water (experienced by most marine taxa at some point in their life cycle), require a well-designed spatial-temporal sampling strategy and analysis. Many genetic summary statistics used to describe populations may be inappropriate for marine species with large population sizes, large species ranges, stochastic recruitment, and asymmetrical gene flow. Finally, statistical approaches for testing associations between seascapes and population genomic patterns are still maturing with no single approach able to capture all relevant considerations. None of these issues are completely unique to marine systems and therefore similar issues and solutions will be shared for many organisms regardless of habitat. Here, we outline goals and spatial approaches for landscape genomics with an emphasis on marine systems and review the growing empirical literature on seascape genomics. We review established tools and approaches and highlight promising new strategies to overcome select issues including a strategy to spatially optimize sampling. Despite the many challenges, we argue that marine systems may be especially well suited for identifying candidate genomic regions under environmentally mediated

Healthcare utilization and expenditure analysis between individuals with intellectual disabilities and the general population in Taiwan: a population-based nationwide child and adolescent study.

PubMed

Chiang, Po-Huang; Chang, Yu-Chia; Lin, Jin-Ding; Tung, Ho-Jui; Lin, Lan-Ping; Hsu, Shang-Wei

2013-09-01

This study examines differences in outpatient-visit frequency and medical expenditures between (1) children and adolescents in Taiwan with intellectual disabilities and (2) children and adolescents in Taiwan's general population. A cross-sectional study was conducted to analyze data from 2007 provided by Taiwan's National Health Insurance program. A total of 236,045 beneficiaries younger than 19 years made use of outpatient services; among them, 35,802 had a principal diagnosis of mental retardation (intellectual disability). The average number of ambulatory visits was 14.9 ± 12.4, which is much higher than in the United States and other developed countries. The mean number of annual visits of the individuals with intellectual disabilities was significantly higher than that of the general population in Taiwan (20.1 ± 20.0 vs. 14.0 ± 12.2); age, gender, urbanization level of residential area, and copayment status affected outpatient visit frequency. The mean annual outpatient costs were NTD6371.3 ± NTD11989.1 for the general population and NTD19724.9 ± NTD40469.9 for those with intellectual disabilities (US $1 equals approximately NTD30). Age, gender, urbanization level of residential area, and copayment status were the determinants that accounted for this difference in cost. Children and adolescents with intellectual disabilities had higher use rates of rehabilitative and psychiatric services than the general population. We conclude that individuals with intellectual disabilities had higher demands than the general population for healthcare services, especially for rehabilitative and psychiatric services. Copyright © 2013 Elsevier Ltd. All rights reserved.

Study design and statistical analysis of data in human population studies with the micronucleus assay.

PubMed

Ceppi, Marcello; Gallo, Fabio; Bonassi, Stefano

2011-01-01

The most common study design performed in population studies based on the micronucleus (MN) assay, is the cross-sectional study, which is largely performed to evaluate the DNA damaging effects of exposure to genotoxic agents in the workplace, in the environment, as well as from diet or lifestyle factors. Sample size is still a critical issue in the design of MN studies since most recent studies considering gene-environment interaction, often require a sample size of several hundred subjects, which is in many cases difficult to achieve. The control of confounding is another major threat to the validity of causal inference. The most popular confounders considered in population studies using MN are age, gender and smoking habit. Extensive attention is given to the assessment of effect modification, given the increasing inclusion of biomarkers of genetic susceptibility in the study design. Selected issues concerning the statistical treatment of data have been addressed in this mini-review, starting from data description, which is a critical step of statistical analysis, since it allows to detect possible errors in the dataset to be analysed and to check the validity of assumptions required for more complex analyses. Basic issues dealing with statistical analysis of biomarkers are extensively evaluated, including methods to explore the dose-response relationship among two continuous variables and inferential analysis. A critical approach to the use of parametric and non-parametric methods is presented, before addressing the issue of most suitable multivariate models to fit MN data. In the last decade, the quality of statistical analysis of MN data has certainly evolved, although even nowadays only a small number of studies apply the Poisson model, which is the most suitable method for the analysis of MN data.

Prevalence of Psychiatric Disorders among the Rural Geriatric Population: A Pilot Study in Karnataka, India

PubMed Central

Nair, Sreejith S.; Raghunath, Pooja; Nair, Sreekanth S.

2015-01-01

Background: Increasing life expectancy around the world, an outstanding achievement of our century, has brought with it new public health challenges. India is the second most populous country in the world, with over 72 million inhabitants above 60 years of age as of 2001. The life expectancy in India increased from 32 years in 1947 to over 66 years in 2010, with 8.0% of the population now reaching over 60 years of age. Few studies in India target the health, especially mental health, of this geriatric population. This study aims to estimate the current prevalence of psychiatric disorders in the geriatric population of the rural area of Singanodi,Karnataka, India. Methods: This cross sectional, epidemiological, community-based study was conducted in a rural health training area of Singanodi, Raichur District, Karnataka, India.The General Health Questionnaire-12, Mini Mental State Examination, and Geriatric Depression Scale were administered to 366 participants. Chi square tests with Yates correction were utilized for statistical analysis using SPSS 19.0 software. Results: We found that 33.9% of the geriatric population in the selected province were above the threshold for mental illness based on the GHQ-12 questionnaire. Females had a higher prevalence of mental disorder at 77.6% (152 out of 196) as compared to males who had a prevalence of 42.4% (72 out of 170). The most common psychiatric disorder was depression (21.9%), and generalized anxiety was present in 10.7% of the study population. Prevalence of cognitive impairment was 16.3%, with a significantly higher percentage of affected individuals in 80+ age group. Conclusion: Mental disorders are common among elderly people, but they are not well documented in rural India. The assessment of psychiatric disorder prevalence will help strengthen psycho-geriatric services and thus improve the quality of life of the elderly. A system that ensures comprehensive health care will have to be developed for this purpose as

Prevalence of Psychiatric Disorders among the Rural Geriatric Population: A Pilot Study in Karnataka, India.

PubMed

Nair, Sreejith S; Raghunath, Pooja; Nair, Sreekanth S

2015-01-01

Increasing life expectancy around the world, an outstanding achievement of our century, has brought with it new public health challenges. India is the second most populous country in the world, with over 72 million inhabitants above 60 years of age as of 2001. The life expectancy in India increased from 32 years in 1947 to over 66 years in 2010, with 8.0% of the population now reaching over 60 years of age. Few studies in India target the health, especially mental health, of this geriatric population. This study aims to estimate the current prevalence of psychiatric disorders in the geriatric population of the rural area of Singanodi,Karnataka, India. This cross sectional, epidemiological, community-based study was conducted in a rural health training area of Singanodi, Raichur District, Karnataka, India.The General Health Questionnaire-12, Mini Mental State Examination, and Geriatric Depression Scale were administered to 366 participants. Chi square tests with Yates correction were utilized for statistical analysis using SPSS 19.0 software. We found that 33.9% of the geriatric population in the selected province were above the threshold for mental illness based on the GHQ-12 questionnaire. Females had a higher prevalence of mental disorder at 77.6% (152 out of 196) as compared to males who had a prevalence of 42.4% (72 out of 170). The most common psychiatric disorder was depression (21.9%), and generalized anxiety was present in 10.7% of the study population. Prevalence of cognitive impairment was 16.3%, with a significantly higher percentage of affected individuals in 80+ age group. Mental disorders are common among elderly people, but they are not well documented in rural India. The assessment of psychiatric disorder prevalence will help strengthen psycho-geriatric services and thus improve the quality of life of the elderly. A system that ensures comprehensive health care will have to be developed for this purpose as part of our future efforts.

Prevalence of rheumatic diseases in adult population in Spain (EPISER 2016 study): Aims and methodology.

PubMed

Seoane-Mato, Daniel; Sánchez-Piedra, Carlos; Silva-Fernández, Lucía; Sivera, Francisca; Blanco, Francisco J; Pérez Ruiz, Fernando; Juan-Mas, Antonio; Pego-Reigosa, José M; Narváez, Javier; Quilis Martí, Neus; Cortés Verdú, Raúl; Antón-Pagés, Fred; Quevedo Vila, Víctor; Garrido Courel, Laura; Del Amo, Natividad Del Val; Paniagua Zudaire, Inmaculada; Añez Sturchio, Gustavo; Medina Varo, Fermín; Ruiz Tudela, María Del Mar; Romero Pérez, Antonio; Ballina, Javier; Brandy García, Anahy; Fábregas Canales, Dolores; Font Gayá, Teresa; Bordoy Ferrer, Carolina; González Álvarez, Beatriz; Casas Hernández, Laura; Álvarez Reyes, Fátima; Delgado Sánchez, Mónica; Martínez Dubois, Cristina; Sánchez-Fernández, Simón Ángel; Rojas Vargas, Luisa Marena; García Morales, Paula Virginia; Olivé, Alejandro; Rubio Muñoz, Paula; Larrosa, Marta; Navarro Ricos, Noemí; Graell Martín, Eduard; Chamizo, Eugenio; Chaves Chaparro, Lara; Rojas Herrera, Sara; Pons Dolset, Jordi; Polo Ostariz, Miguel Ángel; Ruiz-Alejos Garrido, Susana; Macía Villa, Cristina; Cruz Valenciano, Ana; González Gómez, María Luisa; Morcillo Valle, Mercedes; Palma Sánchez, Deseada; Moreno Martínez, María José; Mayor González, Marta; Atxotegi Sáenz de Buruaga, Joana; Urionagüena Onaindia, Irati; Blanco Cáceres, Boris Anthony; Díaz-González, Federico; Bustabad, Sagrario

2017-07-31

To describe the methodology of the EPISER 2016 (study of the prevalence of rheumatic diseases in adult population in Spain), as well its strengths and limitations. The aim of this study is to estimate the prevalence of rheumatoid arthritis (RA), psoriatic arthritis (PsA), ankylosing spondylitis (AS), systemic lupus erythematosus (SLE), Sjögren's syndrome (SS), osteoarthritis (knee, hip, hands, and cervical and lumbar spine), fibromyalgia, gout and clinical osteoporotic fracture. Population-based, multicenter, cross-sectional study, with the participation of 45 municipalities in the 17 Spanish autonomous communities. The reference population will consist of adults aged 20 years and over residing in Spain. A computer-assisted telephone interview (CATI) system will be used for data collection. Diagnostic suspicions and diagnoses received by the participants will be studied by rheumatologists in the referral hospitals in the selected municipalities. the prevalence of the rheumatic diseases will be calculated using estimators and their 95% confidence intervals. Weights will be calculated in each of the sampling stages in accordance with the probability of selection. The distribution of the population in Spain will be obtained from the Spanish Statistics Institute. Sociodemographic and lifestyle changes over the last 16 years justify EPISER 2016. This study will provide current data about the prevalences of RA, AS, PsA, SLE, SS, osteoarthritis, fibromyalgia, gout and clinical osteoporotic fracture. The results will allow comparisons with studies from other countries and EPISER 2000. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

A population-based study of homicide deaths in Ontario, Canada using linked death records.

PubMed

Lachaud, James; Donnelly, Peter D; Henry, David; Kornas, Kathy; Calzavara, Andrew; Bornbaum, Catherine; Rosella, Laura

2017-07-24

Homicide - a lethal expression of violence - has garnered little attention from public health researchers and health policy makers, despite the fact that homicides are a cause of preventable and premature death. Identifying populations at risk and the upstream determinants of homicide are important for addressing inequalities that hinder population health. This population-based study investigates the public health significance of homicides in Ontario, Canada, over the period of 1999-2012. We quantified the relative burden of homicides by comparing the socioeconomic gradient in homicides with the leading causes of death, cardiovascular disease (CVD) and neoplasm, and estimated the potential years of life lost (PYLL) due to homicide. We linked vital statistics from the Office of the Registrar General Deaths register (ORG-D) with Census and administrative data for all Ontario residents. We extracted all homicide, neoplasm, and cardiovascular deaths from 1999 to 2012, using International Classification of Diseases codes. For socioeconomic status (SES), we used two dimensions of the Ontario Marginalization Index (ON-Marg): material deprivation and residential instability. Trends were summarized across deprivation indices using age-specific rates, rate ratios, and PYLL. Young males, 15-29 years old, were the main victims of homicide with a rate of 3.85 [IC 95%: 3.56; 4.13] per 100,000 population and experienced an upward trend over the study period. The socioeconomic neighbourhood gradient was substantial and higher than the gradient for both cardiovascular and neoplasms. Finally, the PYLL due to homicide were 63,512 and 24,066 years for males and females, respectively. Homicides are an important cause of death among young males, and populations living in disadvantaged neighbourhoods. Our findings raise concerns about the burden of homicides in the Canadian population and the importance of addressing social determinants to address these premature deaths.

Populations, Teacher's Guide.

ERIC Educational Resources Information Center

Conard, David; Lawson, Chester A.

This Teacher's Guide is designed for use with the Science Curriculum Improvement Study's (SCIS) unit Population. Populations is the third of a six-unit sequence of SCIS's Life Science Program for grades K-6. The Populations guide consists of activity outlines along with suggestions for guiding children's observation and manipulations of living…

Incorporation of inorganic mercury (Hg²⁺) in pelagic food webs of ultraoligotrophic and oligotrophic lakes: the role of different plankton size fractions and species assemblages.

PubMed

Soto Cárdenas, Carolina; Diéguez, Maria C; Ribeiro Guevara, Sergio; Marvin-DiPasquale, Mark; Queimaliños, Claudia P

2014-10-01

In lake food webs, pelagic basal organisms such as bacteria and phytoplankton incorporate mercury (Hg(2+)) from the dissolved phase and pass the adsorbed and internalized Hg to higher trophic levels. This experimental investigation addresses the incorporation of dissolved Hg(2+) by four plankton fractions (picoplankton: 0.2-2.7 μm; pico+nanoplankton: 0.2-20 μm; microplankton: 20-50 μm; and mesoplankton: 50-200 μm) obtained from four Andean Patagonian lakes, using the radioisotope (197)Hg(2+). Species composition and abundance were determined in each plankton fraction. In addition, morphometric parameters such as surface and biovolume were calculated using standard geometric models. The incorporation of Hg(2+) in each plankton fraction was analyzed through three concentration factors: BCF (bioconcentration factor) as a function of cell or individual abundance, SCF (surface concentration factor) and VCF (volume concentration factor) as functions of individual exposed surface and biovolume, respectively. Overall, this investigation showed that through adsorption and internalization, pico+nanoplankton play a central role leading the incorporation of Hg(2+) in pelagic food webs of Andean lakes. Larger planktonic organisms included in the micro- and mesoplankton fractions incorporate Hg(2+) by surface adsorption, although at a lesser extent. Mixotrophic bacterivorous organisms dominate the different plankton fractions of the lakes connecting trophic levels through microbial loops (e.g., bacteria-nanoflagellates-crustaceans; bacteria-ciliates-crustaceans; endosymbiotic algae-ciliates). These bacterivorous organisms, which incorporate Hg from the dissolved phase and through their prey, appear to explain the high incorporation of Hg(2+) observed in all the plankton fractions. Copyright © 2014 Elsevier B.V. All rights reserved.

Epidemiology of the Emergent Disease Paridae pox in an Intensively Studied Wild Bird Population

PubMed Central

Lachish, Shelly; Lawson, Becki; Cunningham, Andrew A.; Sheldon, Ben C.

2012-01-01

Paridae pox, a novel avipoxvirus infection, has recently been identified as an emerging infectious disease affecting wild tit species in Great Britain. The incursion of Paridae pox to a long-term study site where populations of wild tits have been monitored in detail for several decades provided a unique opportunity to obtain information on the local-scale epidemiological characteristics of this novel infection during a disease outbreak. Using captures of >8000 individual birds, we show that, within two years of initial emergence, Paridae pox had become established within the population of great tits (Parus major) reaching relatively high peak prevalence (10%), but was far less prevalent (<1%) in sympatric populations of several other closely related, abundant Paridae species. Nonlinear smoothing models revealed that the temporal pattern of prevalence among great tits was characterised by within-year fluctuations indicative of seasonal forcing of infection rates, which was likely driven by multiple environmental and demographic factors. There was individual heterogeneity in the course of infection and, although recovery was possible, diseased individuals were far less likely to be recaptured than healthy individuals, suggesting a survival cost of infection. This study demonstrates the value of long-term monitoring for obtaining key epidemiological data necessary to understand disease dynamics, spread and persistence in natural populations. PMID:23185230

High rates of homicide in a rural South African population (2000-2008): findings from a population-based cohort study.

PubMed

Otieno, George; Marinda, Edmore; Bärnighausen, Till; Tanser, Frank

2015-01-01

South Africa has continued to receive increasing attention due to unprecedented high levels of violence. Homicide-related violence accounts for a significant proportion of unnatural deaths and contributes significantly to loss of years of expected life. We investigated levels and factors associated with homicide-related deaths and identify communities with excessively high homicide risk in a typical rural South African population. Data drawn from verbal autopsies conducted on all deaths recorded during annual demographic and health surveillance in KwaZulu Natal, South Africa were used to derive the cumulative probability of death from homicide over a nine-year period (2000-2008). Weibull regression methods were used to investigate factors associated with homicide deaths. A Kulldorff spatial scan statistic was used to identify spatial clusters of homicide-related deaths. With 536 homicide-related deaths, and a median seven years of follow-up, the study found an overall homicide incidence rate of 66 deaths per 100, 000 person-years of observation (PYOs) (95 % CI 60-72) for the period under study. Death related to the use of firearms was the leading reported method of homicide (65 %) and most deaths occurred over weekends (43 %). Homicides are the second-most common cause of death in men aged 25-34 after HIV-related deaths (including TB) in this community, at 210 deaths per 100,000 PYOs, and was highest among 55-64 year old women, at 78 deaths per 100,000 PYOs. Residency status, age, socioeconomic status, and highest education level attained independently predicted the risk of homicide death. The spatial distribution of homicide deaths was not homogenous and the study identified two clear geographical clusters with significantly elevated homicide risk. The high rates of homicide observed in this typical rural South African population - particularly among men - underscore the need for urgent interventions to reduce this tragic and theoretically preventable loss of

Concepts and controversies in estimating vitamin K status in population based studies

USDA-ARS?s Scientific Manuscript database

A better understanding of vitamin K's role in health and disease requires the assessment of vitamin K nutritional status in population and clinical studies. This is primarily accomplished using dietary questionnaires and/or biomarkers. Because food composition databases in the U.S. are most complete...

A population-based study of active and drug-resistant epilepsies in Northern Italy.

PubMed

Giussani, Giorgia; Canelli, Valentina; Bianchi, Elisa; Franchi, Carlotta; Nobili, Alessandro; Erba, Giuseppe; Beghi, Ettore

2016-02-01

Drug-resistant epilepsy (DRE) is defined by the International League Against Epilepsy as a failure of adequate trials of two tolerated, appropriately chosen, and used antiepileptic drugs to achieve sustained seizure freedom. Our aim was to calculate the following: (1) the prevalence of active epilepsy and DRE in a well-defined population of Northern Italy and (2) the proportion of incident cases developing DRE. The study population (146,506; year 2008) resided in the province of Lecco, Northern Italy. The medical records of 123 general practitioners were reviewed to identify patients with epilepsy, diagnosed by a neurologist during the period 2000-2008. The point prevalence of active epilepsy and DRE was calculated on December 31, 2008. A total of 747 prevalent patients with epilepsy, 684 patients with active epilepsy, and 342 incident cases were identified. The frequency of DRE was 15.6% (107/684) of all active epilepsies and 10.5% (36/342) of incident cases. The point prevalence was 0.73 per 1000. The standardized prevalence of DRE was 0.7 per 1000 (Italian population) and 0.8 per 1000 (world population). Our data indicate that 1/6 patients with active epilepsy in the general population has DRE, and 1/10 patients with newly diagnosed epilepsy will develop DRE within nine years from the diagnosis. Copyright © 2015 Elsevier Inc. All rights reserved.

Comparing population exposure to multiple Washington earthquake scenarios for prioritizing loss estimation studies

USGS Publications Warehouse

Wood, Nathan J.; Ratliff, Jamie L.; Schelling, John; Weaver, Craig S.

2014-01-01

Scenario-based, loss-estimation studies are useful for gauging potential societal impacts from earthquakes but can be challenging to undertake in areas with multiple scenarios and jurisdictions. We present a geospatial approach using various population data for comparing earthquake scenarios and jurisdictions to help emergency managers prioritize where to focus limited resources on data development and loss-estimation studies. Using 20 earthquake scenarios developed for the State of Washington (USA), we demonstrate how a population-exposure analysis across multiple jurisdictions based on Modified Mercalli Intensity (MMI) classes helps emergency managers understand and communicate where potential loss of life may be concentrated and where impacts may be more related to quality of life. Results indicate that certain well-known scenarios may directly impact the greatest number of people, whereas other, potentially lesser-known, scenarios impact fewer people but consequences could be more severe. The use of economic data to profile each jurisdiction’s workforce in earthquake hazard zones also provides additional insight on at-risk populations. This approach can serve as a first step in understanding societal impacts of earthquakes and helping practitioners to efficiently use their limited risk-reduction resources.

Development of a Web-Accessible Population Pharmacokinetic Service—Hemophilia (WAPPS-Hemo): Study Protocol

PubMed Central

Foster, Gary; Navarro-Ruan, Tamara; McEneny-King, Alanna; Edginton, Andrea N; Thabane, Lehana

2016-01-01

Background Individual pharmacokinetic assessment is a critical component of tailored prophylaxis for hemophilia patients. Population pharmacokinetics allows using individual sparse data, thus simplifying individual pharmacokinetic studies. Implementing population pharmacokinetics capacity for the hemophilia community is beyond individual reach and requires a system effort. Objective The Web-Accessible Population Pharmacokinetic Service—Hemophilia (WAPPS-Hemo) project aims to assemble a database of patient pharmacokinetic data for all existing factor concentrates, develop and validate population pharmacokinetics models, and integrate these models within a Web-based calculator for individualized pharmacokinetic estimation in patients at participating treatment centers. Methods Individual pharmacokinetic studies on factor VIII and IX concentrates will be sourced from pharmaceutical companies and independent investigators. All factor concentrate manufacturers, hemophilia treatment centers (HTCs), and independent investigators (identified via a systematic review of the literature) having on file pharmacokinetic data and willing to contribute full or sparse pharmacokinetic data will be eligible for participation. Multicompartmental modeling will be performed using a mixed-model approach for derivation and Bayesian forecasting for estimation of individual sparse data. NONMEM (ICON Development Solutions) will be used as modeling software. Results The WAPPS-Hemo research network has been launched and is currently joined by 30 HTCs from across the world. We have gathered dense individual pharmacokinetic data on 878 subjects, including several replicates, on 21 different molecules from 17 different sources. We have collected sparse individual pharmacokinetic data on 289 subjects from the participating centers through the testing phase of the WAPPS-Hemo Web interface. We have developed prototypal population pharmacokinetics models for 11 molecules. The WAPPS-Hemo website

Metric and morphological assessment of facial features: a study on three European populations.

PubMed

Ritz-Timme, S; Gabriel, P; Tutkuviene, J; Poppa, P; Obertová, Z; Gibelli, D; De Angelis, D; Ratnayake, M; Rizgeliene, R; Barkus, A; Cattaneo, C

2011-04-15

Identification from video surveillance systems is becoming more and more frequent in the forensic practice. In this field, different techniques have been improved such as height estimation and gait analysis. However, the most natural approach for identifying a person in everyday life is based on facial characteristics. Scientifically, faces can be described using morphological and metric assessment of facial features. The morphological approach is largely affected by the subjective opinion of the observer, which can be mitigated by the application of descriptive atlases. In addition, this approach requires one to investigate which are the most common and rare facial characteristics in different populations. For the metric approach further studies are necessary in order to point out possible metric differences within and between different populations. The acquisition of statistically adequate population data may provide useful information for the reconstruction of biological profiles of unidentified individuals, particularly concerning ethnic affiliation, and possibly also for personal identification. This study presents the results of the morphological and metric assessment of the head and face of 900 male subjects between 20 and 31 years from Italy, Germany and Lithuania. The evaluation of the morphological traits was performed using the DMV atlas with 43 pre-defined facial characteristics. The frequencies of the types of facial features were calculated for each population in order to establish the rarest characteristics which may be used for the purpose of a biological profile and consequently for personal identification. Metric analysis performed in vivo included 24 absolute measurements and 24 indices of the head and face, including body height and body weight. The comparison of the frequencies of morphological facial features showed many similarities between the samples from Germany, Italy and Lithuania. However, several characteristics were rare or

Mental disorder sick leave in Sweden: A population study.

PubMed

Lidwall, Ulrik; Bill, Sofia; Palmer, Edward; Olsson Bohlin, Christina

2018-01-01

The inability to perform productive work due to mental disorders is a growing concern in advanced societies. To investigate medically certified mental disorder and all-cause sick leave in a working population using demographic, socioeconomic and occupational predictors. The study population was the entire Swedish work force aged 16-64 years in December 31st 2011. The outcome was sick leave exceeding 14 days in 2012 with adjustment for 13 confounders. The risk of sick leave with a mental disorder is higher among women compared to men, among persons aged 30-39 and among parents in families with underage children. Employees in welfare service occupations within health care, education and social services have an elevated risk of mental disorder sick leave and constitute a large proportion of the workforce. The results support the need for improving early detection and prevention of mental disorders in the workforce. Improvements in psychosocial work environments are essential, where the higher risk in female dominated welfare occupations particularly, have repercussions on the quality of the welfare services provided for vulnerable groups in society. Better work-life balance in families with younger children could also mitigate the effects of a high total workload in that particular phase of life.

Infective Endocarditis and Cancer Risk: A Population-Based Cohort Study.

PubMed

Sun, Li-Min; Wu, Jung-Nan; Lin, Cheng-Li; Day, Jen-Der; Liang, Ji-An; Liou, Li-Ren; Kao, Chia-Hung

2016-03-01

This study investigated the possible relationship between endocarditis and overall and individual cancer risk among study participants in Taiwan.We used data from the National Health Insurance program of Taiwan to conduct a population-based, observational, and retrospective cohort study. The case group consisted of 14,534 patients who were diagnosed with endocarditis between January 1, 2000 and December 31, 2010. For the control group, 4 patients without endocarditis were frequency matched to each endocarditis patient according to age, sex, and index year. Competing risks regression analysis was conducted to determine the effect of endocarditis on cancer risk.A large difference was noted in Charlson comorbidity index between endocarditis and nonendocarditis patients. In patients with endocarditis, the risk for developing overall cancer was significant and 119% higher than in patients without endocarditis (adjusted subhazard ratio = 2.19, 95% confidence interval = 1.98-2.42). Regarding individual cancers, in addition to head and neck, uterus, female breast and hematological malignancies, the risks of developing colorectal cancer, and some digestive tract cancers were significantly higher. Additional analyses determined that the association of cancer with endocarditis is stronger within the 1st 5 years after endocarditis diagnosis.This population-based cohort study found that patients with endocarditis are at a higher risk for colorectal cancer and other cancers in Taiwan. The risk was even higher within the 1st 5 years after endocarditis diagnosis. It suggested that endocarditis is an early marker of colorectal cancer and other cancers. The underlying mechanisms must still be explored and may account for a shared risk factor of infection in both endocarditis and malignancy.

Regarding the confusion between the population concept and Mayr's "population thinking".

PubMed

Hey, Jody

2011-12-01

Ernst Mayr said that one of Darwin's greatest contributions was to show scholars the way to population thinking, and to help them discard a mindset of typological thinking. Population thinking rejects a focus on a central representative type, and emphasizes the variation among individuals. However, Mayr's choice of terms has led to confusion, particularly among biologists who study natural populations. Both population thinking and the concept of a biological population were inspired by Darwin, and from Darwin the chain for both concepts runs through Francis Galton who introduced the statistical usage of "population" that appears in Mayr's population thinking. It was Galton's "population" that was modified by geneticists and biometricians in the early 20th century to refer to an interbreeding and evolving community of organisms. Under this meaning, a population is a biological entity and so paradoxically population thinking, which emphasizes variation at the expense of dwelling on entities, is usually not about populations. Mayr did not address the potential for misunderstanding but for him the important part of the population concept was that the organisms within a population were variable, and so he probably thought there should not be confusion between population thinking and the concept of a population.

Influence of population versus convenience sampling on sample characteristics in studies of cognitive aging.

PubMed

Brodaty, Henry; Mothakunnel, Annu; de Vel-Palumbo, Melissa; Ames, David; Ellis, Kathryn A; Reppermund, Simone; Kochan, Nicole A; Savage, Greg; Trollor, Julian N; Crawford, John; Sachdev, Perminder S

2014-01-01

We examined whether differences in findings of studies examining mild cognitive impairment (MCI) were associated with recruitment methods by comparing sample characteristics in two contemporaneous Australian studies, using population-based and convenience sampling. The Sydney Memory and Aging Study invited participants randomly from the electoral roll in defined geographic areas in Sydney. The Australian Imaging, Biomarkers and Lifestyle Study of Ageing recruited cognitively normal (CN) individuals via media appeals and MCI participants via referrals from clinicians in Melbourne and Perth. Demographic and cognitive variables were harmonized, and similar diagnostic criteria were applied to both samples retrospectively. CN participants recruited via convenience sampling were younger, better educated, more likely to be married and have a family history of dementia, and performed better cognitively than those recruited via population-based sampling. MCI participants recruited via population-based sampling had better memory performance and were less likely to carry the apolipoprotein E ε4 allele than clinically referred participants but did not differ on other demographic variables. A convenience sample of normal controls is likely to be younger and better functioning and that of an MCI group likely to perform worse than a purportedly random sample. Sampling bias should be considered when interpreting findings. Copyright © 2014 Elsevier Inc. All rights reserved.

Why Population in 1974?

ERIC Educational Resources Information Center

O'Connor, Marion

1974-01-01

Discusses the impact of world population growth leading to the establishment of the United Nations Fund for Population Activities and to the declaration of 1974 as World Population Year. Previews some of the parameters and interconnecting interests to be considered during this year of intensive population study. (JR)

A new study of China's population control during the past ten years.

PubMed

Wei, J

1989-02-01

This paper summarizes the control of population in China in the past 10 years and the changes that are occurring. Recently, an increase in the number of family members has directly influenced socioeconomic status by increasing family income and improving living conditions. Rural families have no incentives to control the number of children born. The cyclic effect of the 1962-73 baby boom is also causing a recent surge in population. China has studied these problems and has taken the following measures: new family planning systems have been established; population has been controlled macroscopically and flexibility is allowed at an individual level; governmental family planning organizations have been set up and financed; family planning education has been increased; family planning services have been enforced; incentives and restrictions have been implemented. China must work as a whole to enact and enforce these policies. Families must show restraint in childbearing. The only way for this to be accomplished is by decreasing the socioeconomic incentives to have children. Finally, reforms should be in tune with changing situations.

Prevalence and correlates of coronary heart disease: first population-based study in Lebanon.

PubMed

Zeidan, Rouba Karen; Farah, Rita; Chahine, Mirna N; Asmar, Roland; Hosseini, Hassan; Salameh, Pascale; Pathak, Atul

2016-01-01

Lebanon is experiencing a growing epidemic of coronary heart diseases (CHDs), as most low- and middle-income countries currently are. However, this growth can be attenuated if effective preventive strategies are adopted. To provide the first national population-based prevalence of CHD and to describe the profile of Lebanese adults with prevalent CHD. We carried out a cross-sectional study using a multistage cluster sample across Lebanon. We interviewed residents aged 40 years and older using a questionnaire that captured the presence of CHDs and their risk factors (RFs). Our study showed that 13.4% of the Lebanese population aged ≥40 years suffer from a prevalent CHD. CHD seemed to appear more prematurely than in developed countries, and males seemed to be more subject to CHD than females until a certain age. CHD was associated with older age, male sex, a lower economic situation, hypercholesterolemia, hypertension, having a family history of premature cardiovascular diseases, and suffering from diabetes. However, smoking and waist circumference did not seem to have an independent effect on CHD, but rather an effect mediated by biological RFs. This is the first nationwide endeavor conducted in Lebanon to assess the prevalence of CHD. This study also confirms the relevance of the classic RFs of CHD and their applicability to the Lebanese population, thus allowing for prevention strategies.

Enantiomorphism and rule similarity in the astigmatism axes of fellow eyes: A population-based study.

PubMed

Hashemi, Hassan; Asharlous, Amir; Yekta, Abbasali; Ostadimoghaddam, Hadi; Mohebi, Masumeh; Aghamirsalim, Mohamadreza; Khabazkhoob, Mehdi

2018-04-03

To evaluate the relationship patterns between astigmatism axes of fellow eyes (rule similarity and symmetry) and to determine the prevalence of each pattern in the studied population. This population-based study was conducted in 2015 in Iran. All participants had tests for visual acuity, objective refraction, subjective refraction (if cooperative), and assessment of eye health at the slit-lamp. Axis symmetry was based on two different patterns: direct (equal axes) and mirror (mirror image symmetry) or enantiomorphism. Bilateral astigmatism was classified as isorule if fellow eyes had the same orientation (e.g. both eyes were with-the-rule) and as anisorule if otherwise. Of the total cases of bilateral astigmatism, 80% were isorule, and in the studied population, the prevalence of isorule and anisorule astigmatism was 14.89% and 3.53%, respectively. The prevalence of isorule increased with age (p<0.001). The prevalence of both isorule and anisorule increased at higher degrees of spherical ametropia (p<0.001). Median inter-ocular axis difference was 10° in mirror symmetry and 20° in direct symmetry with no significant difference between two genders (p>0.288). Both symmetry patterns reduced with age (p<0.001). Among cases of bilateral astigmatism, 15.5% and 19.8% had exact direct and mirror symmetry, respectively. Bilateral astigmatism is mainly isorule in the population and anisorule astigmatism is rare. The enantiomorphism is the most common pattern in the population of bilateral astigmatism. Copyright © 2018 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

Enabling the participation of marginalized populations: case studies from a health service organization in Ontario, Canada.

PubMed

Montesanti, Stephanie R; Abelson, Julia; Lavis, John N; Dunn, James R

2017-08-01

We examined efforts to engage marginalized populations in Ontario Community Health Centers (CHCs), which are primary health care organizations serving 74 high-risk communities. Qualitative case studies of community participation in four Ontario CHCs were carried out through key informant interviews with CHC staff to identify: (i) the approaches, strategies and methods used in participation initiatives aimed specifically at engaging marginalized populations in the planning of and decision making for health services; and (ii) the challenges and enablers for engaging these populations. The marginalized populations involved in the community participation initiatives studied included Low-German Speaking Mennonites in a rural town, newcomer immigrants and refugees in an urban downtown city, immigrant and francophone seniors in an inner city and refugee women in an inner city. Our analysis revealed that enabling the participation of marginalized populations requires CHCs to attend to the barriers experienced by marginalized populations that constrain their participation. Key informants outlined the features of a 'community development approach' that they rely on to address the barriers to marginalized peoples' involvement by strengthening their skills, abilities and leadership in capacity-building activities. The community development approach also shaped the participation methods that were used in the engagement process of CHCs. However, key informants also described the challenges of applying this approach, influenced by the cultural values of some groups, which shaped their willingness and motivation to participate. This study provides further insight into the approach, strategies and methods used in the engagement process to enable the participation of marginalized populations, which may be transferable to other health services settings. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Population and Environment

PubMed Central

de Sherbinin, Alex; Carr, David; Cassels, Susan; Jiang, Leiwen

2009-01-01

The interactions between human population dynamics and the environment have often been viewed mechanistically. This review elucidates the complexities and contextual specificities of population-environment relationships in a number of domains. It explores the ways in which demographers and other social scientists have sought to understand the relationships among a full range of population dynamics (e.g., population size, growth, density, age and sex composition, migration, urbanization, vital rates) and environmental changes. The chapter briefly reviews a number of the theories for understanding population and the environment and then proceeds to provide a state-of-the-art review of studies that have examined population dynamics and their relationship to five environmental issue areas. The review concludes by relating population-environment research to emerging work on human-environment systems. PMID:20011237

Family Aggregation and Heritability of ESRD in Taiwan: A Population-Based Study.

PubMed

Wu, Hsin Hsu; Kuo, Chang Fu; Li, I Jung; Weng, Cheng Hao; Lee, Cheng Chia; Tu, Kun Hua; Liu, Shou Hsuan; Chen, Yung Chang; Yang, Chih Wei; Luo, Shue Fen; See, Lai Chu; Yu, Kuang Hui; Huang, Lu Hsiang; Zhang, Weiya; Doherty, Michael; Tian, Ya Chung

2017-11-01

Aggregation of end-stage renal disease (ESRD) has been observed in families of European origin, as well as those of African origin. However, it is not well documented if this disease aggregates in Asian families. Furthermore, the contribution of genetic factors and shared environmental factors to family aggregation remains unclear. Population-based cross-sectional cohort study. All 23,422,955 individuals registered in the Taiwan National Health Insurance Research Database in 2013. Among these, 47.45%, 57.45%, 47.29%, and 1.51% had a known parent, child, sibling, or twin, respectively. We identified 87,849 patients who had a diagnosis of ESRD. Family history of ESRD. ESRD and heritability defined as the proportion of phenotypic variance attributable to genetic factors. Having an affected first-degree relative with ESRD was associated with an adjusted relative risk of 2.46 (95% CI, 2.32-2.62). Relative risks were 96.38 (95% CI, 48.3-192.34) for twins of patients with ESRD, 2.15 (95% CI, 2.02-2.29) for parents, 2.78 (95% CI, 2.53-3.05) for offspring, 4.96 (95% CI, 4.19-5.88) for siblings, and 1.66 (95% CI, 1.54-1.78) for spouses without genetic similarities. Heritability in this study was 31.1% to 11.4% for shared environmental factors and 57.5% for nonshared environmental factors. This was a registry database study and we did not have detailed information about clinical findings or the definite causes of ESRD. This whole population-based family study in Asia confirmed, in a Taiwanese population, that a family history of ESRD is a strong risk factor for this disease. Moderate heritability was noted and environmental factors were related to disease. Family history of ESRD is an important piece of clinical information. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Using population mixtures to optimize the utility of genomic databases: linkage disequilibrium and association study design in India.

PubMed

Pemberton, T J; Jakobsson, M; Conrad, D F; Coop, G; Wall, J D; Pritchard, J K; Patel, P I; Rosenberg, N A

2008-07-01

When performing association studies in populations that have not been the focus of large-scale investigations of haplotype variation, it is often helpful to rely on genomic databases in other populations for study design and analysis - such as in the selection of tag SNPs and in the imputation of missing genotypes. One way of improving the use of these databases is to rely on a mixture of database samples that is similar to the population of interest, rather than using the single most similar database sample. We demonstrate the effectiveness of the mixture approach in the application of African, European, and East Asian HapMap samples for tag SNP selection in populations from India, a genetically intermediate region underrepresented in genomic studies of haplotype variation.

Population data of five genetic markers in the Turkish population: comparison with four American population groups.

PubMed

Kurtuluş-Ulküer, M; Ulküer, U; Kesici, T; Menevşe, S

2002-09-01

In this study, the phenotype and allele frequencies of five enzyme systems were determined in a total of 611 unrelated Turkish individuals and analyzed by using the exact and the chi 2 test. The following five red cell enzymes were identified by cellulose acetate electrophoresis: phosphoglucomutase (PGM), adenosine deaminase (ADA), phosphoglucose isomerase (PGI), adenylate kinase (AK), and 6-phosphogluconate dehydrogenase (6-PGD). The ADA, PGM and AK enzymes were found to be polymorphic in the Turkish population. The results of the statistical analysis showed, that the phenotype frequencies of the five enzyme under study are in Hardy-Weinberg equilibrium. Statistical analysis was performed in order to examine whether there are significant differences in the phenotype frequencies between the Turkish population and four American population groups. This analysis showed, that there are some statistically significant differences between the Turkish and the other groups. Moreover, the observed phenotype and allele frequencies were compared with those obtained in other population groups of Turkey.

Methodology of a population-based stroke and TIA incidence and outcomes study: the Auckland Regional Community Stroke Study (ARCOS IV) 2011-2012.

PubMed

Krishnamurthi, Rita; Jones, Amy; Barber, P Alan; Barker-Collo, Suzanne; McPherson, Kathryn; Bennett, Derrick; Rush, Elaine; Suh, Flora; Starkey, Nicola; Theadom, Alice; Parag, Varsha; Rathnasabapathy, Yogini; Feigin, Valery L

2014-01-01

Stroke is a leading cause of death and disability worldwide. Stroke burden is immense as it leads to premature deaths, leaves survivors with ongoing disabilities, and has a major financial impact on the individual, their families, and the community. Reliable, high-quality evidence is needed on stroke risk factors, incidence, and outcomes to provide information on how best to reduce this burden. Population-based studies are regarded as the 'gold-standard' of measuring disease burden but are not common due to the logistical and financial challenges they present. The Auckland Regional Community Stroke Studies are among a few in the world that have been carried out at a population level and at regular intervals. The aim of the fourth Auckland Regional Community Stroke Studies IV is to examine the current measures of stroke incidence, prevalence, and outcomes as well the trends over four decades. This article describes the methodology of the Auckland Regional Community Stroke Studies IV with stroke and transient ischemic attacks cases registered over a 12-month period from March 1, 2011 to February 29, 2012. The methodology described may be used as a guide in order to design similar population-based stroke incidence and outcome studies in other countries and populations, thus facilitating the collection of most consistent and accurate stroke epidemiological data. © 2013 The Authors. International Journal of Stroke © 2013 World Stroke Organization.

Association Between Educational Level and Risk of Cancer in HIV-infected Individuals and the Background Population: Population-based Cohort Study 1995-2011.

PubMed

Legarth, Rebecca; Omland, Lars H; Dalton, Susanne O; Kronborg, Gitte; Larsen, Carsten S; Pedersen, Court; Pedersen, Gitte; Gerstoft, Jan; Obel, Niels

2015-11-15

Human immunodeficiency virus (HIV)-infected individuals have increased risk of cancer. To our knowledge, no previous study has examined the impact of socioeconomic position on risk and prognosis of cancer in HIV infection. Population-based cohort-study, including HIV-infected individuals diagnosed (without intravenous drug abuse or hepatitis C infection) (n = 3205), and a background population cohort matched by age, gender, and country of birth (n = 22 435) were analyzed. Educational level (low or high) and cancer events were identified in Danish national registers. Cumulative incidences, incidence rate ratios (IRRs), and survival using Kaplan-Meier methods were estimated. Low educational level was associated with increased risk of cancer among HIV-infected individuals compared to population controls: all (adjusted-IRRs: 1.4 [95% confidence interval {CI}, 1.1-1.7] vs 1.1 [95% CI, .9-1.2]), tobacco- and alcohol-related (2.1 [95% CI, 1.3-3.4] vs 1.3 [95% CI, 1.1-1.6]), and other (1.7 [95% CI, 1.1-2.8] vs 0.9 [95% CI, .7-1.0]). Educational level was not associated with infection-related or ill-defined cancers. One-year-survival was not associated with educational level, but HIV-infected individuals with low educational level had lower 5-year-survival following infection-related and ill-defined cancers. Education is associated with risk and prognosis of some cancers in HIV infection, and diverges from what is observed in the background population. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Late Causes of Death After Pediatric Cardiac Surgery: A 60-Year Population-Based Study.

PubMed

Raissadati, Alireza; Nieminen, Heta; Haukka, Jari; Sairanen, Heikki; Jokinen, Eero

2016-08-02

Comprehensive information regarding causes of late post-operative death following pediatric congenital cardiac surgery is lacking. The study sought to analyze late causes of death after congenital cardiac surgery by era and defect severity. We obtained data from a nationwide pediatric cardiac surgery database and Finnish population registry regarding patients who underwent cardiac surgery at <15 years of age at 1 of 5 universities or 1 district hospital in Finland from 1953 to 2009. Noncyanotic and cyanotic defects were classified as simple and severe, respectively. Causes of death were determined using International Classification of Diseases diagnostic codes. Deaths among the study population were compared to a matched control population. Overall, 10,964 patients underwent 14,079 operations, with 98% follow-up. Early mortality (<30 days) was 5.6% (n = 613). Late mortality was 10.4% (n = 1,129). Congenital heart defect (CHD)-related death rates correlated with defect severity. Heart failure was the most common mode of CHD-related death, but decreased after surgeries performed between 1990 and 2009. Sudden death after surgery for atrial septal defect, ventricular septal defect, tetralogy of Fallot, and transposition of the great arteries decreased to zero following operations from 1990 to 2009. Deaths from neoplasms, respiratory, neurological, and infectious disease were significantly more common among study patients than controls. Pneumonia caused the majority of non-CHD-related deaths among the study population. CHD-related deaths have decreased markedly but remain a challenge after surgery for severe cardiac defects. Premature deaths are generally more common among patients than the control population, warranting long-term follow-up after congenital cardiac surgery. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Sleep patterns and insomnia among adolescents: a population-based study.

PubMed

Hysing, Mari; Pallesen, Ståle; Stormark, Kjell M; Lundervold, Astri J; Sivertsen, Børge

2013-10-01

The aim of the current study was to examine sleep patterns and rates of insomnia in a population-based study of adolescents aged 16-19 years. Gender differences in sleep patterns and insomnia, as well as a comparison of insomnia rates according to DSM-IV, DSM-V and quantitative criteria for insomnia (Behav. Res. Ther., 41, 2003, 427), were explored. We used a large population-based study in Hordaland county in Norway, conducted in 2012. The sample included 10,220 adolescents aged 16-18 years (54% girls). Self-reported sleep measurements included bedtime, rise time, time in bed, sleep duration, sleep efficiency, sleep onset latency, wake after sleep onset, rate and frequency and duration of difficulties initiating and maintaining sleep and rate and frequency of tiredness and sleepiness. The adolescents reported short sleep duration on weekdays (mean 6:25 hours), resulting in a sleep deficiency of about 2 h. A majority of the adolescents (65%) reported sleep onset latency exceeding 30 min. Girls reported longer sleep onset latency and a higher rate of insomnia than boys, while boys reported later bedtimes and a larger weekday-weekend discrepancy on several sleep parameters. Insomnia prevalence rates ranged from a total prevalence of 23.8 (DSM-IV criteria), 18.5 (DSM-V criteria) and 13.6% (quantitative criteria for insomnia). We conclude that short sleep duration, long sleep onset latency and insomnia were prevalent in adolescents. This warrants attention as a public health concern in this age group. © 2013 European Sleep Research Society.

Pain and learning in primary school: a population-based study.

PubMed

Kosola, Silja; Mundy, Lisa K; Sawyer, Susan M; Canterford, Louise; van der Windt, Danielle A; Dunn, Kate M; Patton, George C

2017-09-01

Despite the frequency of pain among children, little is known about its effects on learning and school outcomes. The objective of this study was to quantify the association of pain and academic achievement while taking into account the presence of co-occurring emotional symptoms. A population-based stratified random sample of 1239 students aged 8 to 9 years from primary schools in Melbourne, Australia, was recruited for the Childhood to Adolescence Transition Study. Children indicated sites of pain that had lasted for a day or longer in the past month using a pain manikin. Depressive- and anxiety-related symptoms were assessed using child-reported items. National assessment results for reading and numeracy were used to measure academic achievement. Sixty-five percent of children reported pain in at least 1 body site and 16% reported chronic pain. Increasing number of pain sites was associated with poorer reading scores in a dose-response fashion (β = -3.1; 95% confidence interval -4.9 to -1.3; P < 0.001). The association was only partly attenuated when adjusting for emotional symptoms (β = -2.6; 95% confidence interval -4.5 to -0.8; P < 0.001) and was not moderated by emotional symptoms. Children with chronic pain were a year behind their peers in both reading and numeracy. Among primary school students, pain was associated with lower reading scores even after adjusting for the presence of emotional symptoms. Although population-based longitudinal studies will be required to ascertain consistency and possible causality, grounds exist for considering pain and emotional symptoms in the assessment of children with reading difficulties.

Population Synthesis Studies of the White Dwarfs of the Galactic Disk and Halo

NASA Astrophysics Data System (ADS)

Cojocaru, Elena-Ruxandra

2016-09-01

White dwarfs are fossil stars that can encode valuable information about the formation, evolution and other properties of the different Galactic stellar populations. They are the direct descendants of main-sequence stars with masses ranging from ∼0.8 M⊙ to ∼10 M⊙, which means that over 95% of the stars in our Galaxy will eventually become white dwarfs. This fact, correlated with the excellent quality of modern white dwarf cooling models, clearly marks their potential as cosmic clocks for estimating the ages of Galactic stellar populations, as well as place white dwarfs as privileged objects in understanding several actual astrophysical problems. Stellar population synthesis methods (Tinsley, 1968) use theoretical evolutionary sequences to reproduce luminosities, temperatures and other parameters building up to a synthetic population that can be readily compared to an observed sample of stars. Such techniques are perfect for the study of the different white dwarf populations in our Galaxy and their strength has only grown in recent years, fueled both by improved evolutionary sequences and detailed cooling tracks and also by the ever growing samples of white dwarfs identified through modern survey missions. In particular, the work presented in this thesis uses an updated population synthesis code based on previous versions of the code from our group (García-Berro et al., 1999; Torres et al., 2002; García-Berro et al., 2004; Torres et al., 2005; Camacho et al., 2014). Our synthetic population code, based on Monte Carlo statistical techniques, has been extensively used in the study of the disk (García-Berro et al., 1! 999; Torres et al., 2001; Torres & García-Berro, 2016) and halo (Torres et al., 2002; García-Berro et al., 2004) single white-dwarf population, white dwarf plus main sequence stars (Camacho et al., 2014), as well as open clusters such as NGC 6791 (García-Berro et al., 2010; García-Berro et al., 2011) or globular clusters, as 47 Tuc (Garc

The population ecology of contemporary adaptations: what empirical studies reveal about the conditions that promote adaptive evolution.

PubMed

Reznick, D N; Ghalambor, C K

2001-01-01

Under what conditions might organisms be capable of rapid adaptive evolution? We reviewed published studies documenting contemporary adaptations in natural populations and looked for general patterns in the population ecological causes. We found that studies of contemporary adaptation fall into two general settings: (1) colonization of new environments that established newly adapted populations, and (2) local adaptations within the context of a heterogeneous environments and metapopulation structure. Local ecological processes associated with colonizations and introductions included exposure to: (1) a novel host or food resource; (2) a new biophysical environment; (3) a new predator community; and (4) a new coexisting competitor. The new environments that were colonized often had depauperate communities, sometimes because of anthropogenic disturbance. Local adaptation in heterogeneous environments was also often associated with recent anthropogenic changes, such as insecticide and herbicide resistance, or industrial melanism. A common feature of many examples is the combination of directional selection with at least a short-term opportunity for population growth. We suggest that such opportunities for population growth may be a key factor that promotes rapid evolution, since directional selection might otherwise be expected to cause population decline and create the potential for local extinction, which is an ever-present alternative to local adaptation. We also address the large discrepancy between the rate of evolution observed in contemporary studies and the apparent rate of evolution seen in the fossil record.

78 FR 12335 - Submission for OMB review; Comment Request: Methodological Studies for the Population Assessment...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-22

...; Comment Request: Methodological Studies for the Population Assessment of Tobacco and Health (PATH) Study... approval from OMB for methodological studies to improve the PATH study instrumentation and data collection procedures. These methodological studies will support ongoing assessment and refinement of the PATH study's...

Environment And Genetics in Lung cancer Etiology (EAGLE) study: an integrative population-based case-control study of lung cancer.

PubMed

Landi, Maria Teresa; Consonni, Dario; Rotunno, Melissa; Bergen, Andrew W; Goldstein, Alisa M; Lubin, Jay H; Goldin, Lynn; Alavanja, Michael; Morgan, Glen; Subar, Amy F; Linnoila, Ilona; Previdi, Fabrizio; Corno, Massimo; Rubagotti, Maurizia; Marinelli, Barbara; Albetti, Benedetta; Colombi, Antonio; Tucker, Margaret; Wacholder, Sholom; Pesatori, Angela C; Caporaso, Neil E; Bertazzi, Pier Alberto

2008-06-06

Lung cancer is the leading cause of cancer mortality worldwide. Tobacco smoking is its primary cause, and yet the precise molecular alterations induced by smoking in lung tissue that lead to lung cancer and impact survival have remained obscure. A new framework of research is needed to address the challenges offered by this complex disease. We designed a large population-based case-control study that combines a traditional molecular epidemiology design with a more integrative approach to investigate the dynamic process that begins with smoking initiation, proceeds through dependency/smoking persistence, continues with lung cancer development and ends with progression to disseminated disease or response to therapy and survival. The study allows the integration of data from multiple sources in the same subjects (risk factors, germline variation, genomic alterations in tumors, and clinical endpoints) to tackle the disease etiology from different angles. Before beginning the study, we conducted a phone survey and pilot investigations to identify the best approach to ensure an acceptable participation in the study from cases and controls. Between 2002 and 2005, we enrolled 2101 incident primary lung cancer cases and 2120 population controls, with 86.6% and 72.4% participation rate, respectively, from a catchment area including 216 municipalities in the Lombardy region of Italy. Lung cancer cases were enrolled in 13 hospitals and population controls were randomly sampled from the area to match the cases by age, gender and residence. Detailed epidemiological information and biospecimens were collected from each participant, and clinical data and tissue specimens from the cases. Collection of follow-up data on treatment and survival is ongoing. EAGLE is a new population-based case-control study that explores the full spectrum of lung cancer etiology, from smoking addiction to lung cancer outcome, through examination of epidemiological, molecular, and clinical data. We have

Quality of life and anxiety disorders: a population study.

PubMed

Cramer, Victoria; Torgersen, Svenn; Kringlen, Einar

2005-03-01

The study of quality of life has increased in importance in the area of mental disorders during the last decade. The aim of the present study was to investigate the effect of specific anxiety disorders on specific quality of life indicators in the common population. More than 2000 individuals between 18 and 65 years old were studied by means of structured interviews. The results showed that social phobia and panic disorder within the past year and lifetime, and generalized anxiety disorder within the past year, had an independent effect on quality of life when controlling for a number of sociodemographic variables, somatic health, and other DSM-III-R Axis I mental disorders. Specific phobias and obsessive compulsive disorder had only a small effect, and agoraphobia showed no effect. The effect was strongest for self-realization and contact with friends, but anxiety disorders also influenced subjective well-being, social support, negative life events, contact with family of origin, and neighborhood quality.

Genealogy construction in a historically isolated population: application to genetic studies of rheumatoid arthritis in the Pima Indian.

PubMed

Lin, J P; Hirsch, R; Jacobsson, L T; Scott, W W; Ma, L D; Pillemer, S R; Knowler, W C; Kastner, D L; Bale, S J

1999-01-01

Due to the characteristics of complex traits, many traits may not be amenable to traditional epidemiologic methods. We illustrate an approach that defines an isolated population as the "unit" for carrying out studies of complex disease. We provide an example using the Pima Indians, a relatively isolated population, in which the incidence and prevalence of Type 2 diabetes, gallbladder disease, and rheumatoid arthritis (RA) are significantly increased compared with the general U.S. population. A previous study of RA in the Pima utilizing traditional methods failed to detect a genetic effect on the occurrence of the disease. Our approach involved constructing a genealogy for this population and using a genealogic index to investigate familial aggregation. We developed an algorithm to identify biological relationships among 88 RA cases versus 4,000 subsamples of age-matched individuals from the same population. Kinship coefficients were calculated for all possible pairs of RA cases, and similarly for the subsamples. The sum of the kinship coefficient among all combination of RA pairs, 5.92, was significantly higher than the average of the 4,000 subsamples, 1.99 (p < 0.001), and was elevated over that of the subsamples to the level of second cousin, supporting a genetic effect in the familial aggregation. The mean inbreeding coefficient for the Pima was 0.00009, similar to that reported for other populations; none of the RA cases were inbred. The Pima genealogy can be anticipated to provide valuable information for the genetic study of diseases other than RA. Defining an isolated population as the "unit" in which to assess familial aggregation may be advantageous, especially if there are a limited number of cases in the study population.

Pilot study of mold populations inside and outside of Puerto Rican residences

EPA Science Inventory

Puerto Rico has the highest asthma prevalence in the US. In the states, mold exposures have been linked to the development and exacerbation of asthma. For a pilot study of mold populations in Puerto Rico, dust and air samples were collected in January 2013 inside and outside of...

Pilot study of mold population inside and outside of Puerto Rican residences

EPA Science Inventory

Abstract: Puerto Rico has the highest asthma prevalence in the US. In the states, mold exposures have been linked to the development and exacerbation of asthma. For a pilot study of mold populations in Puerto Rico, dust and air samples were collected in January 2013 inside and ou...

Two types of population migration in China: a comparative study.

PubMed

Gu, S

1992-01-01

The patterns, extent of, and trends in permanent and temporary migration in China are presented. Permanency is determined by a household registration transfer. Floaters are considered temporary migrants. The regulatory history of migration is given: restrictions prior to 1978 on temporary migration and relaxation of restrictions after 1978. Permanent migration was greatest in the 1950s. Between 1949 and 1960, there were 73.37 million permanent migrants to urban areas from rural areas out of an urban population increase of 105.83 million. During the 1960 and 1970s, urban population was lowered. During the Cultural Revolution, emigration surpassed immigration and the nonagricultural population increased in cities and towns. Between 1976 and 1987, the natural growth of the urban population declined, and nonagricultural population increased from 57.65 million to 204.057 million in cities and towns (1949-88). The trends in the floating population show the lowest ratio of temporary migrants to permanent migrants between 1984 and 1987 to be in Shenyang (15:100); the highest was in Guangzhou (33:100) with an average of 23:100. When the ratio is considered as 20:100 in cities, the average floating population is calculated at 52.87 million in 1987 out of 264.354 million total urban population. 70% were from rural areas. In a comparison of six provinces, Hebei had the lowest percentage of floaters (19%) and Shandong the highest (40%). In country-governed towns, and estimated temporary in-migrants numbered 9.48 million; 8/86 million were floaters. During peak migration, temporary migration averages 50 million/day and permanent migration averages 50,000/day. The primary difference between floaters and permanent migrants is that floaters keep their ties to the land. Surplus labor drives temporary migration, and as such is a release valve. Permanent migration, which is government-controlled, does not allow as much flexibility in adapting to socioeconomic conditions. The sectors

Using Lemna to Study Geometric Population Growth.

ERIC Educational Resources Information Center

DeBuhr, Larry E.

1991-01-01

An experiment in which students collect and analyze data on the population size of a real organism rather that on a model is presented. The activity allows for the integration of mathematics, graphing techniques, and the use of computers. The lesson is designed to follow the learning cycle format. (KR)

Population based study of rates of multiple pregnancies in Denmark, 1980-94.

PubMed Central

Westergaard, T.; Wohlfahrt, J.; Aaby, P.; Melbye, M.

1997-01-01

OBJECTIVE: To study trends in multiple pregnancies not explained by changes in maternal age and parity patterns. DESIGN: Trends in population based figures for multiple pregnancies in Denmark studied from complete national records on parity history and vital status. POPULATION: 497,979 Danish women and 803,019 pregnancies, 1980-94. MAIN OUTCOME MEASURES: National rates of multiple pregnancies, infant mortality, and stillbirths controlled for maternal age and parity. Special emphasis on primiparous women > or = 30 years of age, who are most likely to undergo fertility treatment. RESULTS: The national incidence of multiple pregnancies increased 1.7-fold during 1980-94, the increase primarily in 1989-94 and almost exclusively in primiparous women aged > or = 30 years, for whom the adjusted population based twinning rate increased 2.7-fold and the triplet rate 9.1-fold. During 1989-94, the adjusted yearly increase in multiple pregnancies for these women was 19% (95% confidence interval 16% to 21%) and in dizygotic twin pregnancies 25% (21% to 28%). The proportion of multiple births among infant deaths in primiparous women > or = 30 years increased from 11.5% to 26.9% during the study period. The total infant mortality, however, did not increase for these women because of a simultaneous significant decrease in infant mortality among singletons. CONCLUSIONS: A relatively small group of women has drastically changed the overall national rates of multiple pregnancies. The introduction of new treatments to enhance fertility has probably caused these changes and has also affected the otherwise decreasing trend in infant mortality. Consequently, the resources, both economical and otherwise, associated with these treatments go well beyond those invested in specific fertility enhancing treatments. PMID:9080993

ALS and the Military: A Population-Based Study in the Danish Registries

PubMed Central

Seals, Ryan M.; Kioumourtzoglou, Marianthi-Anna; Gredal, Ole; Hansen, Johnni; Weisskopf, Marc G.

2016-01-01

Background Prior studies have suggested that military service may be associated with the development of amyotrophic lateral sclerosis. We conducted a population-based case-control study in Denmark to assess whether occupation in the Danish military is associated with an increased risk of developing amyotrophic lateral sclerosis. Methods There were 3,650 incident cases of amyotrophic lateral sclerosis recorded in the Danish National Patient Registry between 1982 and 2009. Each case was matched to 100 age- and sex-matched population controls alive and free of amyotrophic lateral sclerosis on the date of the case diagnosis. Comprehensive occupational history was obtained from the Danish Pension Fund database, which began in 1964. Results 2.4% (n=8,922) of controls had a history of employment in the military prior to the index date. Military employees overall had an elevated rate of ALS (OR=1.3; 95% CI: 1.1-1.6). A ten-year increase in years employed by the military was associated with an odds ratio of 1.2 (95% CI: 1.0-1.4), and all quartiles of time employed were elevated. There was little suggestion of a pattern across calendar year of first employment, but there was some evidence that increasing age at first employment was associated with increased ALS rates. Rates were highest in the decade immediately following the end of employment (OR=1.6; 95% CI: 1.2-2.2). Conclusions In this large population-based case-control study, employment by the military is associated with increased rates of ALS. These findings are consistent with earlier findings that military service or employment may entail exposure to risk factors for ALS. PMID:26583610

Exposure to genocide and the risk of schizophrenia: a population-based study.

PubMed

Levine, S Z; Levav, I; Goldberg, Y; Pugachova, I; Becher, Y; Yoffe, R

2016-03-01

No evidence exists on the association between genocide and the incidence of schizophrenia. This study aims to identify critical periods of exposure to genocide on the risk of schizophrenia. This population-based study comprised of all subjects born in European nations where the Holocaust occurred from 1928 to 1945, who immigrated to Israel by 1965 and were indexed in the Population Register (N = 113 932). Subjects were followed for schizophrenia disorder in the National Psychiatric Case Registry from 1950 to 2014. The population was disaggregated to compare groups that immigrated before (indirect exposure: n = 8886, 7.8%) or after (direct exposure: n = 105 046, 92.2%) the Nazi or fascist era of persecutions began. The latter group was further disaggregated to examine likely initial prenatal or postnatal genocide exposures. Cox regression modelling was computed to compare the risk of schizophrenia between the groups, adjusting for confounders. The likely direct group was at a statistically (p < 0.05) greater risk of schizophrenia (hazard ratio = 1.27, 95% confidence interval 1.06-1.51) than the indirect group. Also, the likely combined in utero and postnatal, and late postnatal (over age 2 years) exposure subgroups were statistically at greater risk of schizophrenia than the indirect group (p < 0.05). The likely in utero only and early postnatal (up to age 2 years) exposure subgroups compared with the indirect exposure group did not significantly differ. These results were replicated across three sensitivity analyses. This study showed that genocide exposure elevated the risk of schizophrenia, and identified in utero and postnatal (combined) and late postnatal (age over 2 years) exposures as critical periods of risk.

Set-up and pilot of a population cohort for the study of the natural history of COPD and OSA: the PULSAIB study.

PubMed

Soriano, Joan B; Yáñez, Aina; Renom, Feliu; de la Peña, Mónica; Gómez, Amalia; Duro, Rosa; Uréndez, Ana; Román, Miguel

2010-06-01

We describe the set-up of a population-based study focussed on respiratory conditions, and describe a pilot study - the PULmons SAns Illes Balears (PULSAIB) study - aimed at investigating the natural history of COPD, obstructive sleep apnoea (OSA), and other common chronic diseases. A cross-sectional study was designed to survey two fieldwork areas, one rural and one urban, in the Balearic Islands, Spain. Tests conducted included a questionnaire, spirometry with post-bronchodilator (PBD) test, and portable respiratory polygraphy. We assessed all processes and tools to be used, and piloted them in 175 participants from Bunyola (rural) and 130 participants from the Son Pizà area (urban). Within this first cross-sectional assessment of the Balearic population aged 30 to 80 years, we report the prevalence of airflow limitation defined as a PBD FEV1/FVC ratio <0.7 and the prevalence of OSA defined as an apnoea-hypopnoea index (AHI) >10/hour. A cohort study in the Balearic population to investigate the natural history of COPD and OSA is feasible.

Identification of population substructure among Jews using STR markers and dependence on reference populations included.

PubMed

Listman, Jennifer B; Hasin, Deborah; Kranzler, Henry R; Malison, Robert T; Mutirangura, Apiwat; Sughondhabirom, Atapol; Aharonovich, Efrat; Spivak, Baruch; Gelernter, Joel

2010-06-14

Detecting population substructure is a critical issue for association studies of health behaviors and other traits. Whether inherent in the population or an artifact of marker choice, determining aspects of a population's genetic history as potential sources of substructure can aid in design of future genetic studies. Jewish populations, among which association studies are often conducted, have a known history of migrations. As a necessary step in understanding population structure to conduct valid association studies of health behaviors among Israeli Jews, we investigated genetic signatures of this history and quantified substructure to facilitate future investigations of these phenotypes in this population. Using 32 autosomal STR markers and the program STRUCTURE, we differentiated between Ashkenazi (AJ, N = 135) and non-Ashkenazi (NAJ, N = 226) Jewish populations in the form of Northern and Southern geographic genetic components (AJ north 73%, south 23%, NAJ north 33%, south 60%). The ability to detect substructure within these closely related populations using a small STR panel was contingent on including additional samples representing major continental populations in the analyses. Although clustering programs such as STRUCTURE are designed to assign proportions of ancestry to individuals without reference population information, when Jewish samples were analyzed in the absence of proxy parental populations, substructure within Jews was not detected. Generally, for samples with a given grandparental country of birth, STRUCTURE assignment values to Northern, Southern, African and Asian clusters agreed with mitochondrial DNA and Y-chromosomal data from previous studies as well as historical records of migration and intermarriage.

Identification of population substructure among Jews using STR markers and dependence on reference populations included

PubMed Central

2010-01-01

Background Detecting population substructure is a critical issue for association studies of health behaviors and other traits. Whether inherent in the population or an artifact of marker choice, determining aspects of a population's genetic history as potential sources of substructure can aid in design of future genetic studies. Jewish populations, among which association studies are often conducted, have a known history of migrations. As a necessary step in understanding population structure to conduct valid association studies of health behaviors among Israeli Jews, we investigated genetic signatures of this history and quantified substructure to facilitate future investigations of these phenotypes in this population. Results Using 32 autosomal STR markers and the program STRUCTURE, we differentiated between Ashkenazi (AJ, N = 135) and non-Ashkenazi (NAJ, N = 226) Jewish populations in the form of Northern and Southern geographic genetic components (AJ north 73%, south 23%, NAJ north 33%, south 60%). The ability to detect substructure within these closely related populations using a small STR panel was contingent on including additional samples representing major continental populations in the analyses. Conclusions Although clustering programs such as STRUCTURE are designed to assign proportions of ancestry to individuals without reference population information, when Jewish samples were analyzed in the absence of proxy parental populations, substructure within Jews was not detected. Generally, for samples with a given grandparental country of birth, STRUCTURE assignment values to Northern, Southern, African and Asian clusters agreed with mitochondrial DNA and Y-chromosomal data from previous studies as well as historical records of migration and intermarriage. PMID:20546593

Mediterranean diet and telomere length in Nurses' Health Study: population based cohort study.

PubMed

Crous-Bou, Marta; Fung, Teresa T; Prescott, Jennifer; Julin, Bettina; Du, Mengmeng; Sun, Qi; Rexrode, Kathryn M; Hu, Frank B; De Vivo, Immaculata

2014-12-02

To examine whether adherence to the Mediterranean diet was associated with longer telomere length, a biomarker of aging. Population based cohort study. Nurses' Health Study, an ongoing prospective cohort study of 121,700 nurses enrolled in 1976; in 1989-90 a subset of 32,825 women provided blood samples. 4676 disease-free women from nested case-control studies within the Nurses' Health Study with telomere length measured who also completed food frequency questionnaires. Association between relative telomere lengths in peripheral blood leukocytes measured by quantitative real time polymerase chain reaction and Alternate Mediterranean Diet score calculated from self reported dietary data. Greater adherence to the Mediterranean diet was associated with longer telomeres after adjustment for potential confounders. Least squares mean telomere length z scores were -0.038 (SE 0.035) for the lowest Mediterranean diet score groups and 0.072 (0.030) for the highest group (P for trend = 0.004). In this large study, greater adherence to the Mediterranean diet was associated with longer telomeres. These results further support the benefits of adherence to the Mediterranean diet for promoting health and longevity. © Crous-Bou et al 2014.

Comparative study of the female gametogenic cycle in three populations of Buccinanops globulosus (Caenogastropoda: Nassariidae) from Patagonia

NASA Astrophysics Data System (ADS)

Avaca, María Soledad; Martín, Pablo; van der Molen, Silvina; Narvarte, Maite

2015-03-01

The populations of Buccinanops globulosus from three different sites of northern Patagonia were compared in the female reproductive cycle over a 2-year study period (September 2006-August 2008). These populations differed in demographic and life-history traits (sex ratios, size frequency distributions, growth rates and fecundity). Also, two of these populations show imposex-affected females (Bahía San Antonio, BSA and Bahía Nueva, BN), whereas the other (Playa Villarino, PV) is imposex-free and constitutes a commercial fishery ground for this species. The gametogenic activity of this species has not been studied earlier. Females showed the same gonadal stages in the three populations; however, there were differences in the female size at which each gonadal stage occurred. Monthly variation in gonadal stages and in oocyte size indicated that females of B. globulosus showed a seasonal gametogenic pattern without the occurrence of a resting period. Evacuation of mature oocytes (up to 252.5 µm) occurred mainly from September to December (austral spring) in BSA and PV and from December to March (austral summer) in BN. Gonad maturation and the presence of females carrying egg capsules in the field coincided with changes in water surface temperature and a longer day length. Our results indicate that the occurrence of imposex in the populations studied apparently does not affect the gametogenic activity in females. This study provides further insights into the reproductive biology of B. globulosus. The identification of population variation in reproductive traits should lead to more effective management of the species.

A genetic study and meta-analysis of the genetic predisposition of prostate cancer in a Chinese population.

PubMed

Marzec, Jacek; Mao, Xueying; Li, Meiling; Wang, Meilin; Feng, Ninghan; Gou, Xin; Wang, Guomin; Sun, Zan; Xu, Jianfeng; Xu, Hua; Zhang, Xiaoping; Zhao, Shan-Chao; Ren, Guoping; Yu, Yongwei; Wu, Yudong; Wu, Ji; Xue, Yao; Zhou, Bo; Zhang, Yanling; Xu, Xingxing; Li, Jie; He, Weiyang; Benlloch, Sara; Ross-Adams, Helen; Chen, Li; Li, Jucong; Hong, Yingqia; Kote-Jarai, Zsofia; Cui, Xingang; Hou, Jianguo; Guo, Jianming; Xu, Lei; Yin, Changjun; Zhou, Yuanping; Neal, David E; Oliver, Tim; Cao, Guangwen; Zhang, Zhengdong; Easton, Douglas F; Chelala, Claude; Al Olama, Ali Amin; Eeles, Rosalind A; Zhang, Hongwei; Lu, Yong-Jie

2016-04-19

Prostate cancer predisposition has been extensively investigated in European populations, but there have been few studies of other ethnic groups. To investigate prostate cancer susceptibility in the under-investigated Chinese population, we performed single-nucleotide polymorphism (SNP) array analysis on a cohort of Chinese cases and controls and then meta-analysis with data from the existing Chinese prostate cancer genome-wide association study (GWAS). Genotyping 211,155 SNPs in 495 cases and 640 controls of Chinese ancestry identified several new suggestive Chinese prostate cancer predisposition loci. However, none of them reached genome-wide significance level either by meta-analysis or replication study. The meta-analysis with the Chinese GWAS data revealed that four 8q24 loci are the main contributors to Chinese prostate cancer risk and the risk alleles from three of them exist at much higher frequencies in Chinese than European populations. We also found that several predisposition loci reported in Western populations have different effect on Chinese men. Therefore, this first extensive single-nucleotide polymorphism study of Chinese prostate cancer in comparison with European population indicates that four loci on 8q24 contribute to a great risk of prostate cancer in a considerable large proportion of Chinese men. Based on those four loci, the top 10% of the population have six- or two-fold prostate cancer risk compared with men of the bottom 10% or median risk respectively, which may facilitate the design of prostate cancer genetic risk screening and prevention in Chinese men. These findings also provide additional insights into the etiology and pathogenesis of prostate cancer.

A study of cranial variations based on craniometric indices in a South Indian population.

PubMed

Kanchan, Tanuj; Krishan, Kewal; Gupta, Anadi; Acharya, Jenash

2014-09-01

Human skull has been the most extensively studied bone for establishing the taxonomies at evolutionary levels. Crania are also the most commonly used skeletal elements in population studies because they are known to be more genetically driven and less affected by environmental factors. The craniofacial indices are considered as clinical anthropometric parameters used in the investigation of craniofacial skeletal deformities and brain development. The present research is an attempt to study the cranial indices in the South Indian population. The sample for the study included 118 dry adult crania. All the osteometric measurements were taken using standard anthropometric instruments, and 3 indices, namely, cranial index, orbital index (OI), and index of foreman magnum (FMI), were calculated. Cranial index is calculated as (maximum cranial breadth / maximum cranial length) × 100, OI as (orbital height / orbital breadth) × 100, and FMI as (transverse diameter / anteroposterior diameter) × 100. The crania were further classified based on these indices. The cranial index ranged between 66.67 and 85.71 (mean, 78.57 [SD, 4.11]), the OI ranged between 68.89 and 102.63 (mean, 84.23 [SD, 6.64]), and the FMI ranged between 68.57 and 96.88 (mean, 79.71 [SD, 6.98]). Cranial index did not show any significant correlation with the OI (r = -0.162, P = 0.081) or the FMI (r = -0.045, P = 0.626). A statistically significant correlation was, however, observed between OI and FMI (r = -0.232, P = 0.012). The current study developed population-specific classification of crania using cranial indices. This craniometric baseline data pertaining to the craniofacial indices may be useful in presurgical planning and the postsurgical evaluation. It may also assist the forensic anthropologists in the categorization of human skulls, which may be an important component in identification of highly decomposed dead bodies and skeletal remains. More such studies need to be conducted to understand the

Population demographics of two local South Carolina mourning dove populations

USGS Publications Warehouse

McGowan, D.P.; Otis, D.L.

1998-01-01

The mourning dove (Zenaida macroura) call-count index had a significant (P 2,300 doves and examined >6,000 individuals during harvest bag checks. An age-specific band recovery model with time- and area-specific recovery rates, and constant survival rates, was chosen for estimation via Akaike's Information Criterion (AIC), likelihood ratio, and goodness-of-fit criteria. After-hatching-year (AHY) annual survival rate was 0.359 (SE = 0.056), and hatching-year (HY) annual survival rate was 0.118 (SE = 0.042). Average estimated recruitment per adult female into the prehunting season population was 3.40 (SE = 1.25) and 2.32 (SE = 0.46) for the 2 study areas. Our movement data support earlier hypotheses of nonmigratory breeding and harvested populations in South Carolina. Low survival rates and estimated population growth rate in the study areas may be representative only of small-scale areas that are heavily managed for dove hunting. Source-sink theory was used to develop a model of region-wide populations that is composed of source areas with positive growth rates and sink areas of declining growth. We suggest management of mourning doves in the Southeast might benefit from improved understanding of local population dynamics, as opposed to regional-scale population demographics.

Numbers, Numbers, Numbers: The Role of Population Studies in Social Studies and Global Education

ERIC Educational Resources Information Center

Moore, James R.

2008-01-01

Population trends--birth and death rates, immigration patterns, sex ratios, and life expectancies--are one of the most important issues facing the international community. These trends' relationship to the world economy, the environment, and developing countries' ability to meet the needs of growing populations is a topic appropriate for the…

Population growth, fecundity, and survivorship in recovering populations of bighorn sheep

USGS Publications Warehouse

Singer, F.J.; Williams, E.; Miller, M.W.; Zeigenfuss, L.C.

2000-01-01

The single greatest obstacle to the restoration of large, healthy, populations of bighorn sheep (Ovis canadensis) in the western United States is epizootic outbreaks of bronchopneumonia that may kill 20–100% of the animals in populations. Although the species is capable of rapid initial growth rates following restoration into new habitat (λ = 1.23–1.30 have been observed), these rates of increase are typical only a few years following the release of a population, and then most populations either decline to extirpation or remnant status (<30 animals) or remain at <100 individuals. We studied the fecundity and survivorship of three increasing, and three declining and suspected diseased, populations of bighorn sheep (the latter were subjected to outbreaks of bronchopneumonia) located in or near several large national parks in the western United States from 1991 to 1996. Titers verified both population categories were exposed to the bacteria Pasteurella haemolytica serotypes 3; 4; and 3, 4, 10; Moraxella sp., and parainfluenza-3 and bluetongue (BT) viruses. Pregnancy rates of adult ewes were not different in increasing or decreasing populations (pooled rate = 0.93; p = 0.57), but pregnancy rates of yearlings were lower (0.00 for decreasing vs. 0.33 for increasing populations), initial production of lambs and annual recruitment of lambs was lower (0.14, decreasing vs. 0.66, p < 0.05). Adult survival was lower during the first year of an epizootic, 0.62, in one population, but recovered to 0.85 by the second and subsequent years. Survival of adult rams was variable in diseased populations; in two populations rams appeared to be disproportionately impacted, but in a third population rams survived better during the epizootic. In all the increasing park (unhunted) populations, adult ram survival (0.94 ± 0.01) was higher than adult ewe survival (0.89 ± 0.02) (p = 0.10), in contrast to published information from hunted populations where ram survival was lower