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Sample records for large sexual populations

  1. The Sex, Age, and Me study: recruitment and sampling for a large mixed-methods study of sexual health and relationships in an older Australian population.

    PubMed

    Lyons, Anthony; Heywood, Wendy; Fileborn, Bianca; Minichiello, Victor; Barrett, Catherine; Brown, Graham; Hinchliff, Sharron; Malta, Sue; Crameri, Pauline

    2017-02-21

    Older people are often excluded from large studies of sexual health, as it is assumed that they are not having sex or are reluctant to talk about sensitive topics and are therefore difficult to recruit. We outline the sampling and recruitment strategies from a recent study on sexual health and relationships among older people. Sex, Age and Me was a nationwide Australian study that examined sexual health, relationship patterns, safer-sex practices and STI knowledge of Australians aged 60 years and over. The study used a mixed-methods approach to establish baseline levels of knowledge and to develop deeper insights into older adult's understandings and practices relating to sexual health. Data collection took place in 2015, with 2137 participants completing a quantitative survey and 53 participating in one-on-one semi-structured interviews. As the feasibility of this type of study has been largely untested until now, we provide detailed information on the study's recruitment strategies and methods. We also compare key characteristics of our sample with national estimates to assess its degree of representativeness. This study provides evidence to challenge the assumptions that older people will not take part in sexual health-related research and details a novel and successful way to recruit participants in this area.

  2. Paraphilic Sexual Interests and Sexually Coercive Behavior: A Population-Based Twin Study.

    PubMed

    Baur, Elena; Forsman, Mats; Santtila, Pekka; Johansson, Ada; Sandnabba, Kenneth; Långström, Niklas

    2016-07-01

    Prior research with selected clinical and forensic samples suggests associations between paraphilic sexual interests (e.g., exhibitionism and sexual sadism) and sexually coercive behavior. However, no study to date used a large, representative and genetically informative population sample to address the potential causal nature of this association. We used self-report data on paraphilic and sexually coercive behavior from 5990 18- to 32-year-old male and female twins from a contemporary Finnish population cohort. Logistic regression and co-twin control models were employed to examine if paraphilic behaviors were causally related to coercive behavior or if suggested links were confounded by familial (genetic or common family environment) risk factors. Results indicated that associations between four out of five tested paraphilic behaviors (exhibitionism, masochism, sadism, and voyeurism, respectively) and sexually coercive behavior were moderate to strong. Transvestic fetishism was not independently associated with sexual coercion. Comparisons of twins reporting paraphilic behavior with their paraphilic behavior-discordant twin further suggested that associations were largely independent of shared genetic and environmental confounds, consistent with a causal association. In conclusion, similar to previously reported predictive effects of paraphilias on sexual crime recidivism, paraphilic behavior among young adults in the general population increases sexual offending risk. Further, early identification of paraphilic interest and preventive interventions with at-risk individuals might also reduce perpetration of first-time sexual violence.

  3. [Impact of backward sexual viewpoints on population development].

    PubMed

    Wang, B

    1991-04-01

    In the development of human society, the reproductive function was considered the sole purpose of sexual activities. Any other purposes were deemed abnormal or deviant. The prevalence of that viewpoint reflected the needs during the transformation from hunting to farming as major means of production of the society and the needs for large populations under the socioeconomic conditions of rural society. With the low level of productivity in a family-oriented economy, further development depended on the number of labor hands in the family. The wars for extension of territory and for survival need a constant supply of soldiers. Under such circumstances, the need for large populations implied the importance of fertility behavior in sexual relations. In the rural farming societies, fertility was important in strengthening and developing the family wealth, status, and family structure. Blood relations were emphasized in rural society for family inheritance, for expansion of family influence, and for old age support. The rapid decline of fertility in Europe at the beginning of this century was proposed by some Chinese scholars as the result of their citizens pursuing individual happiness including in sexual relations. The use of contraceptives prevented couples from being overburdened with children. These concepts on sexual relations facilitated the decline of fertility. The necessary social and economic conditions and advances in technology are already present for the changes of the traditional concepts toward sexual relations. The united efforts of social agencies in promoting these changes will be an efficient ensure in regulating the speed of population growth.

  4. Sexual coercion experience and sexually coercive behavior: a population study of Swedish and Norwegian male youth.

    PubMed

    Seto, Michael C; Kjellgren, Cecilia; Priebe, Gisela; Mossige, Svein; Svedin, Carl Göran; Långström, Niklas

    2010-08-01

    The authors tested the hypothesis that experiencing sexual coercion and engaging in sexually coercive behavior are positively associated in a representative sample totaling almost 4,000 Swedish or Norwegian male high school students (estimated response rate 80%). In both surveys, youths who had experienced sexual coercion were approximately three times more likely to engage in sexually coercive behavior than those without such experience (10%-12% vs. 4%). The association between sexual coercion experience and sexually coercive behavior was attenuated but remained significant and moderately strong in both surveys when controlling for nonsexual antisocial behavior, substance use, and noncoercive sexual behavior in multivariate logistic regression models. The population attributable fraction (proportion of sexually coercive behavior that can be explained by sexual coercion experience) was 18%-25%. The findings support a robust link between having been sexually coerced and engaging in coercive sexual behavior in the general population.

  5. Does reproductive isolation evolve faster in larger populations via sexually antagonistic coevolution?

    PubMed

    Gay, L; Eady, P E; Vasudev, R; Hosken, D J; Tregenza, T

    2009-10-23

    Sexual conflict over reproductive investment can lead to sexually antagonistic coevolution and reproductive isolation. It has been suggested that, unlike most models of allopatric speciation, the evolution of reproductive isolation through sexually antagonistic coevolution will occur faster in large populations as these harbour greater levels of standing genetic variation, receive larger numbers of mutations and experience more intense sexual selection. We tested this in bruchid beetle populations (Callosobruchus maculatus) by manipulating population size and standing genetic variability in replicated lines derived from founders that had been released from sexual conflict for 90 generations. We found that after 19 generations of reintroduced sexual conflict, none of our treatments had evolved significant overall reproductive isolation among replicate lines. However, as predicted, measures of reproductive isolation tended to be greater among larger populations. We discuss our methodology, arguing that reproductive isolation is best examined by performing a matrix of allopatric and sympatric crosses whereas measurement of divergence requires crosses with a tester line.

  6. Geographic variation in sexual selection among populations of an iguanid lizard, Sauromalus obesus (=ater).

    PubMed

    Kwiatkowski, Matthew A; Sullivan, Brian K

    2002-10-01

    Geographic variation in selection pressures may result in population divergence and speciation, especially if sexual selection varies among populations. Yet spatial variation in targets and intensity of sexual selection is well studied in only a few species. Even more rare are simultaneous studies of multiple populations combining observations from natural settings with controlled behavioral experiments. We investigated how sexual selection varies among populations of the chuckwalla, Sauromalus obesus. Chuckwallas are sexually dimorphic in color, and males vary in coloration among populations. Using field observations and multiple regression techniques, we investigated how sexual selection acts on various male traits in three populations in which males differed in coloration. The influence of sexual selection on male coloration was then investigated in more detail using controlled experiments. Results from field observations indicate that phenotypic selection was acting on territory quality in all three populations. In two populations, selection was also acting either directly or indirectly on male coloration. Male color likely functions as an indicator of food resources to females because male color is based partly on carotenoid pigments. In controlled experiments, significantly more females from these two populations chose males with brighter colors over dull males, a result consistent with studies on carotenoid pigments in other taxa. In a third population, no evidence of sexual selection on male coloration was found in either the field study or controlled experiment. Lack of female preferences for male color in this population, in which chuckwalla densities are low and home ranges are large, may result from searching costs to females.

  7. FEMALE SEXUALITY, NATIONALISM AND LARGE GROUP IDENTITY.

    PubMed

    Gonzalez-Torres, Miguel Angel; Fernández-Rivas, Aranzazu

    2015-12-01

    Nationalist movements are emerging today everywhere in the world. Many of them display a high level of aggression and a negative attitude toward sexuality and especially female sexuality. Along with this, erotic fiction with a sadomasochistic orientation has achieved great success and has hundreds of millions of readers in the world. This collective fantasy allows some integration of aggression in sexual life while questioning liberal morality and its equality in gender roles and conservative morality and its idea of control over passion. Both phenomena may represent different responses to the appearance of a new female sexuality threatening the social structure we know.

  8. Measuring happiness in large population

    NASA Astrophysics Data System (ADS)

    Wenas, Annabelle; Sjahputri, Smita; Takwin, Bagus; Primaldhi, Alfindra; Muhamad, Roby

    2016-01-01

    The ability to know emotional states for large number of people is important, for example, to ensure the effectiveness of public policies. In this study, we propose a measure of happiness that can be used in large scale population that is based on the analysis of Indonesian language lexicons. Here, we incorporate human assessment of Indonesian words, then quantify happiness on large-scale of texts gathered from twitter conversations. We used two psychological constructs to measure happiness: valence and arousal. We found that Indonesian words have tendency towards positive emotions. We also identified several happiness patterns during days of the week, hours of the day, and selected conversation topics.

  9. Natural Selection in Large Populations

    NASA Astrophysics Data System (ADS)

    Desai, Michael

    2011-03-01

    I will discuss theoretical and experimental approaches to the evolutionary dynamics and population genetics of natural selection in large populations. In these populations, many mutations are often present simultaneously, and because recombination is limited, selection cannot act on them all independently. Rather, it can only affect whole combinations of mutations linked together on the same chromosome. Methods common in theoretical population genetics have been of limited utility in analyzing this coupling between the fates of different mutations. In the past few years it has become increasingly clear that this is a crucial gap in our understanding, as sequence data has begun to show that selection appears to act pervasively on many linked sites in a wide range of populations, including viruses, microbes, Drosophila, and humans. I will describe approaches that combine analytical tools drawn from statistical physics and dynamical systems with traditional methods in theoretical population genetics to address this problem, and describe how experiments in budding yeast can help us directly observe these evolutionary dynamics.

  10. Fraternal Birth Order, Handedness, and Sexual Orientation in a Chinese Population.

    PubMed

    Xu, Yin; Zheng, Yong

    2017-01-01

    We examined the relationship between handedness, fraternal birth order, and sexual orientation in a Chinese population, and analyzed the influence of the components assessing sexual orientation and criteria classifying individuals as homosexual on this relationship. A large sample of heterosexual, bisexual, and homosexual men and women participated in a web-based survey. Our results showed that homosexual women are more likely to be non-right-handed than heterosexual women, regardless of how sexual orientation was defined, whereas bisexual women are more likely to be non-right-handed than heterosexual women when sexual orientation was assessed via sexual attraction and sexual identity. Bisexual men are more likely to be non-right-handed than heterosexual men when sexual orientation was assessed via sexual attraction. We found neither a fraternal birth-order effect nor an interaction between sibling sex ratio, handedness, and sexual orientation. The small number of siblings may be the reason why we could not replicate the fraternal birth-order effect in this Chinese population, which highlights the importance of cultural differences in the understanding of handedness, fraternal birth order, and sexual orientation.

  11. Population structure and diversity in sexual and asexual populations of the pathogenic fungus Melampsora lini

    PubMed Central

    BARRETT, LUKE G.; THRALL, PETER H.; BURDON, JEREMY J.; NICOTRA, ADRIENNE B.; LINDE, CELESTE C.

    2009-01-01

    Many pathogens undergo both sexual and asexual reproduction to varying degrees, yet the ecological, genetic and evolutionary consequences of different reproductive strategies remain poorly understood. Here we investigate the population genetic structure of wild populations of the plant pathogen Melampsora lini on its host Linum marginale, using amplified fragment length polymorphism (AFLP) markers, two genes underlying pathogen virulence, and phenotypic variation in virulence. In Australia, M. lini occurs as two genetically and geographically divergent lineages (AA and AB), one of which is completely asexual (AB), and the other able to reproduce both clonally and sexually (AA). To quantify the genetic and evolutionary consequences of these different life histories, we sampled five populations in each of two biogeographical regions. Analysis of AFLP data obtained for 275 isolates revealed largely disjunct geographical distributions for the two different lineages, low genetic diversity within lineages, and strong genetic structure among populations within each region. We also detected significant divergence among populations for both Avr genes and virulence phenotypes, although generally these values were lower than those obtained with AFLP markers. Furthermore, isolates belonging to lineage AA collectively harboured significantly higher genotypic and phenotypic diversity than lineage AB isolates. Together these results illustrate the important roles of reproductive modes and geographical structure in the generation and maintenance of virulence diversity in populations of M. lini. PMID:18573166

  12. The Association between Childhood and Adolescent Sexual Abuse and Proxies for Sexual Risk Behavior: A Random Sample of the General Population of Sweden

    ERIC Educational Resources Information Center

    Steel, Jennifer L.; Herlitz, Claes A.

    2005-01-01

    Objective: Several studies with small and ''high risk'' samples have demonstrated that a history of childhood or adolescent sexual abuse (CASA) is associated with sexual risk behaviors (SRBs). However, few studies with large random samples from the general population have specifically examined the relationship between CASA and SRBs with a…

  13. Sexual reproduction in Aspergillus flavus sclerotia: acquisition of novel alleles from soil populations and uniparental mitochondrial inheritance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aspergillus flavus colonizes agricultural commodities worldwide and contaminates them with carcinogenic aflatoxins. The high genetic diversity of A. flavus populations is largely due to sexual reproduction characterized by the formation of ascospore-bearing ascocarps embedded within sclerotia. A. ...

  14. The evolution of harm--effect of sexual conflicts and population size.

    PubMed

    Gay, Laurène; Hosken, David J; Eady, Paul; Vasudev, Ram; Tregenza, Tom

    2011-03-01

    Conflicts of interest between mates can promote the evolution of male traits that reduce female fitness and that drive coevolution between the sexes. The rate of adaptation depends on the intensity of selection and its efficiency, which depends on drift and genetic variability. This leads to the largely untested prediction that coevolutionary adaptations such as those driven by sexual conflict should evolve faster in large populations. We tested this using the bruchid beetle Callosobruchus maculatus, a species where harm inflicted by males is well documented. Although most experimental evolution studies remove sexual conflict, we reintroduced it in populations in which it had been experimentally removed. Both population size and standing genetic variability were manipulated in a factorial experimental design. After 90 generations of relaxed conflict (monogamy), the reintroduction of sexual conflicts for 30 generations favored males that harmed females and females that were more resistant to the genital damage inflicted by males. Males evolved to become more harmful when population size was large rather than when initial genetic variation was enriched. Our study shows that sexual selection can create conditions in which males can benefit from harming females and that selection may tend to be more intense and effective in larger populations.

  15. An ephemeral sexual population of Phytophthora infestans in the northeastern United States and Canada

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phytophthora infestans, the causal agent of late blight disease, has been reported in North America since the mid-nineteenth century. In the United States the lack of or very limited sexual reproduction has resulted in largely clonal populations of P. infestans. In 2010 and 2011, but not in 2012 or ...

  16. Population genetic structure of sexual and parthenogenetic damselflies inferred from mitochondrial and nuclear markers

    PubMed Central

    Lorenzo-Carballa, M O; Hadrys, H; Cordero-Rivera, A; Andrés, J A

    2012-01-01

    It has been postulated that obligate asexual lineages may persist in the long term if they escape from negative interactions with either sexual lineages or biological enemies; and thus, parthenogenetic populations will be more likely to occur in places that are difficult for sexuals to colonize, or those in which biological interactions are rare, such as islands or island-like habitats. Ischnura hastata is the only known example of natural parthenogenesis within the insect order Odonata, and it represents also a typical example of geographic parthenogenesis, as sexual populations are widely distributed in North America, whereas parthenogenetic populations of this species have only been found at the Azores archipelago. In order to gain insight in the origin and distribution of parthenogenetic I. hastata lineages, we have used microsatellites, mitochondrial and nuclear DNA sequence data, to examine the population genetic structure of this species over a wide geographic area. Our results suggest that sexual populations of I. hastata in North America conform to a large subdivided population that has gone through a recent spatial expansion. A recent single long distance dispersal event, followed by a demographic expansion, is the most parsimonious hypothesis explaining the origin of the parthenogenetic population of this species in the Azores islands. PMID:21915148

  17. Increasing access by priority populations to Australian sexual health clinics.

    PubMed

    Ali, Hammad; Donovan, Basil; Fairley, Christopher K; Chen, Marcus Y; O'Connor, Catherine C; Grulich, Andrew E; McNulty, Anna; Ryder, Nathan; Hellard, Margaret E; Guy, Rebecca J

    2013-10-01

    Data from a network of 35 Australian sexual health clinics, in geographically diverse locations, showed that the number and proportion of patients from priority populations (ie, young people, men who have sex with men, indigenous people, and female sex workers) increased significantly between 2004 and 2011.

  18. Migration, Multiple Sexual Partnerships, and Sexual Concurrency in the Garífuna Population of Honduras.

    PubMed

    Gandhi, Anisha D; Pettifor, Audrey; Barrington, Clare; Marshall, Stephen W; Behets, Frieda; Guardado, Maria Elena; Farach, Nasim; Ardón, Elvia; Paz-Bailey, Gabriela

    2015-09-01

    The Garífuna, an ethnic minority group in Honduras, have been disproportionately affected by HIV. Previous research suggests that migration and high rates of multiple sexual partnerships are major drivers of the epidemic. Using data from a 2012 population-based survey, we assessed whether temporary migration was associated with (1) multiple sexual partnerships and (2) sexual concurrency among Garífuna men and women in Honduras. Among both men and women, temporary migration in the last year was associated with an increased likelihood of multiple sexual partnerships and with concurrency, though only the association between migration and multiple sexual partnerships among men was statistically significant (Adjusted Prevalence Ratio 1.7, 95 % CI 1.2-2.4). Migration may contribute to HIV/STI vulnerability among Garífuna men and women via increases in these sexual risk behaviors. Research conducted among men and women at elevated risk of HIV should continue to incorporate measures of mobility, including history of internal migration.

  19. Migration, multiple sexual partnerships, and sexual concurrency in the Garífuna population of Honduras

    PubMed Central

    Gandhi, Anisha D.; Pettifor, Audrey; Barrington, Clare; Marshall, Stephen W.; Behets, Frieda; Guardado, Maria Elena; Farach, Nasim; Ardón, Elvia; Paz-Bailey, Gabriela

    2015-01-01

    The Garífuna, an ethnic minority group in Honduras, have been disproportionately affected by HIV. Previous research suggests that migration and high rates of multiple sexual partnerships are major drivers of the epidemic. Using data from a 2012 population-based survey, we assessed whether temporary migration was associated with 1) multiple sexual partnerships and 2) sexual concurrency among Garífuna men and women in Honduras. Among both men and women, temporary migration in the last year was associated with an increased likelihood of multiple sexual partnerships and with concurrency, though only the association between migration and multiple sexual partnerships among men was statistically significant (Adjusted Prevalence Ratio 1.7, 95% CI 1.2-2.4). Migration may contribute to HIV/STI vulnerability among Garífuna men and women via increases in these sexual risk behaviors. Research conducted among men and women at elevated risk of HIV should continue to incorporate measures of mobility, including history of internal migration. PMID:26242612

  20. Sexual recombination punctuated by outbreaks and clonal expansions predicts Toxoplasma gondii population genetics

    PubMed Central

    Grigg, Michael E.; Sundar, Natarajan

    2009-01-01

    The cosmopolitan parasitic pathogen Toxoplasma gondii is capable of infecting essentially any warm-blooded vertebrate worldwide, including most birds and mammals, and establishes chronic infections in one-third of the globe’s human population. The success of this highly prevalent zoonosis is largely the result of its ability to propagate both sexually and clonally. Frequent genetic exchanges via sexual recombination among extant parasite lineages that mix in the definitive felid host produces new lines that emerge to expand the parasite’s host range and cause outbreaks. Highly successful lines spread clonally via carnivorism and in some cases sweep to pandemic levels. The extent to which sexual reproduction versus clonal expansion shapes Toxoplasma’s current, global population genetic structure is the central question this review will attempt to answer. PMID:19217909

  1. Sexual activity and concerns in people with coronary heart disease from a population-based study

    PubMed Central

    Steptoe, Andrew; Jackson, Sarah E; Wardle, Jane

    2016-01-01

    Objective Sexual activity is a central component of intimate relationships, but sexual function may be impaired by coronary heart disease (CHD). There have been few representative population-based comparisons of sexual behaviour and concerns in people with and without CHD. We therefore investigated these issues in a large nationally representative sample of older people. Methods We analysed cross-sectional data from 2979 men and 3711 women aged 50 and older from the English Longitudinal Study of Ageing. Sexual behaviour and concerns were assessed by validated self-completion questionnaire and analyses were weighted for non-response. Covariates included age, partnerships status and comorbidities. Results There were 376 men and 279 women with CHD. Men with CHD were less likely to be sexually active (68.7% vs 80.0%, adjusted OR 0.62, 95% CI 0.47 to 0.81), thought less about sex (74.7% vs 81.9%, OR 0.72, CI 0.54 to 0.95), and reported more erectile difficulties (47.4% vs 38.1%, OR 1.46, CI 1.10 to 1.93) than men without CHD. Effects were more pronounced among those diagnosed within the past 4 years. Women diagnosed <4 years ago were also less likely to be sexually active (35.4% vs 55.6%, OR 0.44, CI 0.23 to 0.84). There were few differences in concerns about sexual activity. Cardiovascular medication showed weak associations with erectile dysfunction. Conclusions There is an association between CHD and sexual activity, particularly among men, but the impact of CHD is limited. More effective advice after diagnosis might reverse the reduction in sexual activity, leading to improved quality of life. PMID:27126394

  2. Sexual behaviour and condom use as a protection against sexually transmitted infections in student population.

    PubMed

    Dijanić, Tomislav; Kozul, Karlo; Miskulin, Maja; Medić, Alan; Jurcev-Savicević, Anamarija; Burazin, Jelena

    2014-03-01

    (chi2 = 13.384, p < 0.05), and also plan to use it during following intercourse in the permanent relationship (chi2 = 17.575, p < 0.01). Growing condom use and decreasing risky sexual behaviour among students, as well as other adolescents and young adults needs to be maintained. Youth should learn before sexual initiation that only correct condom use at every sexual intercourse protects them against STI and human immunodeficiency virus (HIV). Sexual education and STI/HIV prevention programmes, positive role of media (television) and civil organisations that communicate with the youth can help that. Such changes among adolescents and young adults should have to be seen in student population as well.

  3. Highlights of the sexual activity of the heterosexual population in the province of Quebec

    PubMed Central

    Brisson, M.; Boily, M. C.; Masse, B. R.; Adrien, A.; Leaune, V.

    1999-01-01

    OBJECTIVES: To describe and quantify the level of sexual activity of the heterosexually active population of Quebec. METHODS: The data analysed included 2889 heterosexually active individuals aged 15-60 (agemed = 32) from a 1996-7 survey on the sexual lifestyles of the general population of Quebec. Various probability distributions were studied to assess their capacity to describe and quantify the lifetime and yearly numbers of sexual partners of the sampled population. To estimate the annual rates of new partner acquisition, a generalised linear model was fitted to the number of lifetime sexual partners as a function of age, years of sexual activity, and sex. RESULTS: The mean and variance of the number of lifetime sexual partners for men (mean = 11, s2 = 163) is higher than for women (mean = 6, s2 = 72). The negative binomial and lognormal probability distributions give the most adequate fit to the lifetime number of partners for both agglomerated and stratified (by sex and age) data. The estimated annual rates of new partner acquisition provide two important results for prevention: (1) the first year of sexual activity represents the highest annual rate of new partner acquisition independent of age, (2) annual rates of new partner acquisitions increase through mid-life (ages 40-50) combined with a decrease in condom use. CONCLUSION: Problems caused by the use of large categories in the estimation of mean and variance cannot totally be overcome by fitting probability distributions to the empirical data despite good fits. Furthermore, we believe that adequate estimates of the annual rate of new partner acquisition should be a better measure of the risk of HIV infection than the number of partners since the first is a measure of incidence while the second is a measure of prevalence. 




 PMID:10616351

  4. Considerations for Reaching the Latino Population with Sexuality and HIV/AIDS Information and Education.

    ERIC Educational Resources Information Center

    de la Vega, Ernesto

    1990-01-01

    Latino and Latina sexual attitudes and behaviors must be understood if educators and counselors hope to reach this population with effective sexuality and Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome (HIV/AIDS) information and education. The general U.S. Latino population is mostly sexually conservative; direct talk in public…

  5. Natural and sexual selection in a monogamous historical human population

    PubMed Central

    Courtiol, Alexandre; Pettay, Jenni E.; Jokela, Markus; Rotkirch, Anna; Lummaa, Virpi

    2012-01-01

    Whether and how human populations exposed to the agricultural revolution are still affected by Darwinian selection remains controversial among social scientists, biologists, and the general public. Although methods of studying selection in natural populations are well established, our understanding of selection in humans has been limited by the availability of suitable datasets. Here, we present a study comparing the maximum strengths of natural and sexual selection in humans that includes the effects of sex and wealth on different episodes of selection. Our dataset was compiled from church records of preindustrial Finnish populations characterized by socially imposed monogamy, and it contains a complete distribution of survival, mating, and reproductive success for 5,923 individuals born 1760–1849. Individual differences in early survival and fertility (natural selection) were responsible for most variation in fitness, even among wealthier individuals. Variance in mating success explained most of the higher variance in reproductive success in males compared with females, but mating success also influenced reproductive success in females, allowing for sexual selection to operate in both sexes. The detected opportunity for selection is in line with measurements for other species but higher than most previous reports for human samples. This disparity results from biological, demographic, economic, and social differences across populations as well as from failures by most previous studies to account for variation in fitness introduced by nonreproductive individuals. Our results emphasize that the demographic, cultural, and technological changes of the last 10,000 y did not preclude the potential for natural and sexual selection in our species. PMID:22547810

  6. Combat Deployment is Associated With Sexual Harassment or Sexual Assault in a Large, Female Military Cohort

    DTIC Science & Technology

    2013-10-11

    Women who deployed and reported combat experiences were significantly more likely to report sexual harassment (odds ratio [OR], 2.20; 95% confidence...experiences (Table 2). Women who were deployed who experi enced combat reported the highest cumulative incidence of sexual harassment (19.9%) and sexual ... sexual harassment and sexual assault (OR, 2.47; 95% CI, 1.61 3.78), but not the sexual assault only category. Women who deployed before baseline had

  7. Rate of fixation of beneficial mutations in sexual populations

    NASA Astrophysics Data System (ADS)

    Gouveia, Joseilme F.; de Oliveira, Viviane M.; Sátiro, Caio; Campos, Paulo R. A.

    2009-06-01

    We have investigated the rate of substitution of advantageous mutations in populations of haploid organisms where the rate of recombination can be controlled. We have verified that in all the situations recombination speeds up adaptation through recombination of beneficial mutations from distinct lineages in a single individual, and so reducing the intensity of clonal interference. The advantage of sex for adaptation is even stronger when deleterious mutations occur since now recombination can also restore genetic background free of deleterious mutations. However, our simulation results demonstrate that evidence of clonal interference, as increased mean selective effect of fixed mutations and reduced likelihood of fixation of small-effect mutations, are also present in sexual populations. What we see is that this evidence is delayed when compared to asexual populations.

  8. Adolescent sexuality in Asia: new focus for population policy.

    PubMed

    Robey, B

    1989-09-01

    As the age at marriage continues to rise in East and Southeast Asia, the fertility behavior of unmarried teenagers is receiving more attention from population policymakers. In addition to fertility reduction through family planning, Asian societies today consider population planning strategies in relation to national needs and social goals, including such matters as the population's growth rate, age structure, educational quality and skills. The number of single youth in Asia is growing much more rapidly than the total youth population. By the year 2010, for example, India is projected to have nearly 70 million single teenagers, aged 15-19, 188% more than in 1980. In many developing countries today, such as the Philippines and Korea, the rising age at marriage has combined with rapid urbanization, improved status for women, and more educational opportunity to alter both the behavioral norms of young people and the traditional means of social control over youth. Studies of contemporary adolescent sexuality have been conducted in 4 Asian countries. In the Philippines an overt independent youth homosexual culture was found to exist in urban and to some extent rural areas. In Thailand research revealed little conservative resistance to family planning or to contraceptives for young unmarried people. Surveys in Taiwan indicate that behavior related to dating and choice of spouse has become more liberal, and a survey in Hong Kong revealed a higher level of premarital sex and use of prostitutes among Chinese men than expected. Population policy perspectives that need to be considered in these changing times include: 1) issues of access to family planning services by unmarried people below the legal age of maturity; 2) the development of social institutions, such as exist in Thailand and the Philippines, to guide adolescents' behavior; 3) more extensive study of adolescent sexuality; 4) establishment of the scope of family policy.

  9. Divergence in androgen sensitivity contributes to population differences in sexual dimorphism of electrocommunication behavior

    PubMed Central

    Ho, Winnie W.; Rack, Jessie M.; Smith, G. Troy

    2013-01-01

    Weakly-electric fish (Apteronotidae) produce highly diverse electrocommunication signals. Electric organ discharges (EODs) vary across species, sexes, and in the magnitude and direction of their sexual dimorphism. Gonadal steroid hormones can modulate EODs, and differences in androgen sensitivity are hypothesized to underlie variation in the degree of sexual dimorphism across species. In this study, we asked whether variation in androgen sensitivity explained variation in sexual dimorphism of EODs within species, at the population level. We examined two populations of black ghost knifefish (Apteronotus albifrons), one from the Orinoco and the other from the Amazon river basin. EOD frequency (EODf) and chirp rates were measured to characterize diversity in sexual dimorphism across populations. The magnitude of sexual dimorphism in EODf differed significantly across populations, and was more pronounced in the Orinoco population than in the Amazon population. Chirp rates were sexually monomorphic in both populations. 11-ketotestosterone (11-kT) was administered over a two-week period to assess population differences in sensitivity to androgens. 11-kT masculinized EODf significantly more in the population with the greater degree of sexual dimorphism. 11-kT had no effect on the sexually monomorphic chirping rates. We conclude that population divergence in androgen sensitivity contributes to variation in sexual dimorphism of EODf in A. albifrons. PMID:23142327

  10. Polyandry and postcopulatory sexual selection in a wild population.

    PubMed

    Turnell, Biz R; Shaw, Kerry L

    2015-12-01

    When females mate multiply, postcopulatory sexual selection can occur via sperm competition and cryptic female choice. Although postcopulatory selection has the potential to be a major force in driving evolution, few studies have estimated its strength in natural populations. Likewise, although polyandry is widespread across taxa and is the focus of a growing body of research, estimates of natural female mating rates are still limited in number. Microsatellites can be used to estimate the number of mates represented in females' sperm stores and the number of sires contributing to their offspring, enabling comparisons both of polyandry and of two components of postcopulatory selection: the proportion of males that mate but fail to sire offspring, and the degree of paternity skew among the males that do sire offspring. Here, we estimate the number of mates and sires among wild females in the Hawaiian swordtail cricket Laupala cerasina. We compare these estimates to the actual mating rates and paternity shares we observed in a semi-natural population. Our results show that postcopulatory sexual selection operates strongly in this species: wild females mated with an average minimum of 3.6 males but used the sperm from only 58% of them. Furthermore, among the males that did sire offspring, paternity was significantly skewed. These patterns were similar to those observed in the field enclosure, where females mated with an average of 5.7 males and used the sperm from 62% of their mates, with paternity significantly skewed among the sires.

  11. Alleles versus genotypes: Genetic interactions and the dynamics of selection in sexual populations

    NASA Astrophysics Data System (ADS)

    Neher, Richard

    2010-03-01

    Physical interactions between amino-acids are essential for protein structure and activity, while protein-protein interactions and regulatory interactions are central to cellular function. As a consequence of these interactions, the combined effect of two mutations can differ from the sum of the individual effects of the mutations. This phenomenon of genetic interaction is known as epistasis. However, the importance of epistasis and its effects on evolutionary dynamics are poorly understood, especially in sexual populations where recombination breaks up existing combinations of alleles to produce new ones. Here, we present a computational model of selection dynamics involving many epistatic loci in a recombining population. We demonstrate that a large number of polymorphic interacting loci can, despite frequent recombination, exhibit cooperative behavior that locks alleles into favorable genotypes leading to a population consisting of a set of competing clones. As the recombination rate exceeds a certain critical value this ``genotype selection'' phase disappears in an abrupt transition giving way to ``allele selection'' - the phase where different loci are only weakly correlated as expected in sexually reproducing populations. Clustering of interacting sets of genes on a chromosome leads to the emergence of an intermediate regime, where localized blocks of cooperating alleles lock into genetic modules. Large populations attain highest fitness at a recombination rate just below critical, suggesting that natural selection might tune recombination rates to balance the beneficial aspect of exploration of genotype space with the breaking up of synergistic allele combinations.

  12. No Evidence for Long-Term Causal Associations Between Symptoms of Premature Ejaculation and Symptoms of Anxiety, Depression, and Sexual Distress in a Large, Population-Based Longitudinal Sample.

    PubMed

    Ventus, Daniel; Gunst, Annika; Kärnä, Antti; Jern, Patrick

    2017-02-01

    Premature ejaculation (PE) is one of the most common male sexual complaints, but its etiology is unclear. Psychological problems, such as symptoms of anxiety and depression, have traditionally been seen as causal or maintaining etiological components of PE, and previous cross-sectional studies have found weak positive associations between them. The aim of the present study was to test possible causal pathways over time between PE and symptoms of the psychological problems anxiety, depression, and sexual distress. A sample of 985 male Finnish twins and brothers of twins completed a questionnaire in 2006 and 2012. Significant bivariate correlations were found both within and across time between PE and the psychological problems. When fitting structural equation models to test hypothesized causal pathways, symptoms of anxiety and sexual distress at the first measurement time point did not predict future PE. Likewise, PE symptoms at the first measurement did not predict increments or decrements in anxiety, sexual distress, or depression later on. These null findings regarding hypothesized associations may partly be explained by the relatively long time between measurements, or that the measures possibly did not capture the aspects of anxiety that are related to PE.

  13. Population generation for large-scale simulation

    NASA Astrophysics Data System (ADS)

    Hannon, Andrew C.; King, Gary; Morrison, Clayton; Galstyan, Aram; Cohen, Paul

    2005-05-01

    Computer simulation is used to research phenomena ranging from the structure of the space-time continuum to population genetics and future combat.1-3 Multi-agent simulations in particular are now commonplace in many fields.4, 5 By modeling populations whose complex behavior emerges from individual interactions, these simulations help to answer questions about effects where closed form solutions are difficult to solve or impossible to derive.6 To be useful, simulations must accurately model the relevant aspects of the underlying domain. In multi-agent simulation, this means that the modeling must include both the agents and their relationships. Typically, each agent can be modeled as a set of attributes drawn from various distributions (e.g., height, morale, intelligence and so forth). Though these can interact - for example, agent height is related to agent weight - they are usually independent. Modeling relations between agents, on the other hand, adds a new layer of complexity, and tools from graph theory and social network analysis are finding increasing application.7, 8 Recognizing the role and proper use of these techniques, however, remains the subject of ongoing research. We recently encountered these complexities while building large scale social simulations.9-11 One of these, the Hats Simulator, is designed to be a lightweight proxy for intelligence analysis problems. Hats models a "society in a box" consisting of many simple agents, called hats. Hats gets its name from the classic spaghetti western, in which the heroes and villains are known by the color of the hats they wear. The Hats society also has its heroes and villains, but the challenge is to identify which color hat they should be wearing based on how they behave. There are three types of hats: benign hats, known terrorists, and covert terrorists. Covert terrorists look just like benign hats but act like terrorists. Population structure can make covert hat identification significantly more

  14. Effects of natural and sexual selection on adaptive population divergence and premating isolation in a damselfly.

    PubMed

    Svensson, Erik I; Eroukhmanoff, Fabrice; Friberg, Magne

    2006-06-01

    The relative strength of different types of directional selection has seldom been compared directly in natural populations. A recent meta-analysis of phenotypic selection studies in natural populations suggested that directional sexual selection may be stronger in magnitude than directional natural selection, although this pattern may have partly been confounded by the different time scales over which selection was estimated. Knowledge about the strength of different types of selection is of general interest for understanding how selective forces affect adaptive population divergence and how they may influence speciation. We studied divergent selection on morphology in parapatric, natural damselfly (Calopteryx splendens) populations. Sexual selection was stronger than natural selection measured on the same traits, irrespective of the time scale over which sexual selection was measured. Visualization of the fitness surfaces indicated that population divergence in overall morphology is more strongly influenced by divergent sexual selection rather than natural selection. Courtship success of experimental immigrant males was lower than that of resident males, indicating incipient sexual isolation between these populations. We conclude that current and strong sexual selection promotes adaptive population divergence in this species and that premating sexual isolation may have arisen as a correlated response to divergent sexual selection. Our results highlight the importance of sexual selection, rather than natural selection in the adaptive radiation of odonates, and supports previous suggestions that divergent sexual selection promotes speciation in this group.

  15. Sexual disorders among elderly: An epidemiological study in south Indian rural population

    PubMed Central

    Sathyanarayana Rao, T. S.; Ismail, Shajahan; Darshan, M. S.; Tandon, Abhinav

    2015-01-01

    Background: Realizing a dearth of data on this topic, especially in the Indian context, an epidemiological study was conducted in a south Indian rural population to identify the sexual activity patterns and sexual problems among the population above 60 years of age. Objectives: (1) Assessment of sexual activity patterns among individuals above 60 years. (2) Assessment of the prevalence of sexual disorders among individuals above 60 years. Materials and Methods: The study sample consisted of 259 participants, which included both males and females above 60 years of age. Subjects who were sexually active and fulfilled the study criteria were administered Arizona Sexual Experience Scale as a screening tool, for the presence of sexual problems. Those who were found to have sexual problems were interviewed further using appropriate questionnaires. Results: Only 27.4% of the individuals above 60 years were sexually active, and it progressively dropped as age advanced and none were sexually active after 75 years of age. Among the sexually active males, erectile dysfunction (ED) was prevalent in 43.5%, premature ejaculation in 10.9%, hypoactive sexual desire disorder (HSSD) in 0.77% and anorgasmia in 0.38% of the subjects. Among females, arousal disorder was prevalent in 28%, HSSD in 16%, anorgasmia in 20% and dyspareunia in 8% of the subjects. Conclusion: The study gives us an insight into the sexual problems of the elderly and brings home the point that sexual problems are very much common among both men and women in the older population. Among elderly males, ED is the most common sexual disorder whereas in elderly females, arousal disorder is the most prevalent female sexual dysfunction, implicating biology plays an important role in men, whereas psychology plays an important role in women sexual functioning. PMID:26600575

  16. Measuring Community Connectedness among Diverse Sexual Minority Populations

    PubMed Central

    Frost, David M.; Meyer, Ilan H.

    2011-01-01

    Theory and research agree that connectedness to the lesbian, gay, bisexual, and transgender (LGBT) community is an important construct to account for in understanding issues related to health and well-being among gay and bisexual men. However, the measurement of this construct among lesbian and bisexual women or racial/ethnic minority individuals has not yet been adequately investigated. This study examined the reliability and validity of an existing measure of Connectedness to the LGBT Community among a diverse group of sexual minority individuals in New York City and whether differences in connectedness existed across gender and race/ethnicity. Scores on the measure demonstrated both internal consistency and construct stability across subgroups defined by gender and race/ethnicity. The subgroups did not differ in their mean levels of connectedness and scores on the measure demonstrated factorial, convergent, and discriminate validity both generally and within each of the subgroups. Inconsistencies were observed with regard to which scores on the measure demonstrated predictive validity in their associations with indicators of mental health and well-being. The scale is a useful tool for researchers and practitioners interested in understanding the role of community connectedness in the lives of diverse populations of sexual minority individuals. PMID:21512945

  17. Sexual Reproduction in a Simple Growth Population Model

    NASA Astrophysics Data System (ADS)

    Lemos, Carlos Gentil Oro; Santos, Marcio

    2012-05-01

    One of the most important characteristics in the survival of a species is related to the kind of reproduction responsible for the offspring generation. However, only in the last years the role played by sexual reproduction has been investigated. Then, for a better understanding of this kind of process we introduce, in this work, a surface reaction model that describes the role of the sexual reproduction. In our model two different elements of the species, representing male and female, can interact to reproduce a new element. The sex of this new element is chosen with a given probability and in order to take into account the mortality rate we introduce another kind of individual. The value of the spatial density of this element remains constant during the time evolution of the system. The model is studied using Monte Carlo simulations and mean field approximation. Depending on the values of the control parameters of the model, the system can attain two stationary states: In one of them the population survives and in the other it can be extinguished. Besides, accordingly to our results, the phase diagram of the model shows a discontinuous transition between these two states.

  18. Sexual offender recidivism among a population-based prison sample.

    PubMed

    Rettenberger, Martin; Briken, Peer; Turner, Daniel; Eher, Reinhard

    2015-04-01

    The present study examines recidivism rates in sexual offenders using officially registered reconvictions in a representative data set of N = 1,115 male sexual offenders from Austria. In general, results indicate that most sexual offenders do not reoffend sexually after release from prison. More detailed, within the first 5 years after release, the sexual recidivism rate was 6% for the total sample, 4% for the rapist subgroup, and 8% for the child molester subgroup. The findings confirmed previous studies about sex offender recidivism which have shown that first-time sexual offenders are significantly less likely to sexually reoffend than those with previous sexual convictions. With regard to the relationship between age and sexual recidivism, the results challenged the traditional assumption of a clear linear function between age and recidivism. Taken together, compared with previous studies, the recidivism rates found in the present investigation are substantially lower than previous research has indicated.

  19. Improving asthma outcomes in large populations.

    PubMed

    Schatz, Michael; Zeiger, Robert S

    2011-08-01

    This article summarizes our experience using administrative, survey, and telephone information to define asthma severity, impairment, risk, and quality of care in our large Kaiser Permanente population. Our data suggest that the 2-year Healthcare Effectiveness Data and Information Set definition of persistent asthma is a good surrogate for survey-defined persistent asthma, and thus it would be reasonable to direct asthma population management and quality-of-care assessments at patients with Healthcare Effectiveness Data and Information Set-defined persistent asthma for 2 years in a row. For population management, the numbers of short-acting β-agonist (SABA) canisters dispensed and validated tools on mail or telephone surveys have been used to assess asthma impairment. Algorithms based on pharmacy data (SABA canister and oral corticosteroid dispensings and prior emergency hospital care) have been used to assess the risk domain of asthma control. The asthma medication ratio (controllers divided by controllers plus SABAs) has been shown to be related to improved outcomes and is recommended as an asthma quality-of-care marker. It is hoped that outreach to patients and providers based on these indicators will improve asthma outcomes in patients cared for in individual practices, as well as in large health plans.

  20. Natural and sexual selection in a wild insect population.

    PubMed

    Rodríguez-Muñoz, R; Bretman, A; Slate, J; Walling, C A; Tregenza, T

    2010-06-04

    The understanding of natural and sexual selection requires both field and laboratory studies to exploit the advantages and avoid the disadvantages of each approach. However, studies have tended to be polarized among the types of organisms studied, with vertebrates studied in the field and invertebrates in the lab. We used video monitoring combined with DNA profiling of all of the members of a wild population of field crickets across two generations to capture the factors predicting the reproductive success of males and females. The factors that predict a male's success in gaining mates differ from those that predict how many offspring he has. We confirm the fundamental prediction that males vary more in their reproductive success than females, and we find that females as well as males leave more offspring when they mate with more partners.

  1. Susceptibility of large populations of coupled oscillators

    NASA Astrophysics Data System (ADS)

    Daido, Hiroaki

    2015-01-01

    It is an important and interesting problem to elucidate how the degree of phase order in a large population of coupled oscillators responds to a synchronizing periodic force from the outside. Here this problem is studied analytically as well as numerically by introducing the concept of susceptibility for globally coupled phase oscillators with either nonrandom or random interactions. It is shown that the susceptibility diverges at the critical point in the nonrandom case with Widom's equality satisfied, while it exhibits a cusp in the most random case.

  2. Identifying sexual dimorphism in a paediatric South Indian population using stepwise discriminant function analysis.

    PubMed

    Shankar, S; Anuthama, Krishnamurthy; Kruthika, M; Kumar, V Suresh; Ramesh, K; Jaheerdeen, A; Yasin, M Mohamed

    2013-08-01

    Anthropological research relies on skeletal and dental remains for the identification of species. Sexual dimorphism is the systematic difference in form between males and females of the same species. This study is designed to compute a new formula for sex determination using discriminant function analysis in the deciduous crown dimensions of a paediatric population of South Indian origin and to check its accuracy. The sample consisted of 93 females and 90 males of South Indian origin aged between 5 and 13 years. Alginate impressions of the upper dental arch were made and casts were poured immediately. A digital vernier calliper was used to obtain measurements. Teeth considered for measurement were deciduous maxillary canines and molars. Our study is a maiden attempt in considering diagonal measurements along with mesiodistal (MD) and buccolingual (BL) dimensions as predictor variables for sex determination. Statistical analysis was performed using the Statistical Package for the Social Science version 17.0 software. By using the Student t-test, the different predictor variables of teeth selected between male and females were found to be significant (p < 0.05). Highly significant sexual dimorphism was found in the mean MD dimension of maxillary right canine and right and left first molar, BL dimension of right first molar, distobuccal-mesiolingual of right and left first molar and right second molar and mesiobuccal-distolingual of right second molar. The percentage of sexual dimorphism in MD dimensions revealed that the right upper first molar was the most dimorphic tooth and the upper first molar of the left side was the least dimorphic of the six teeth studied. The present study found the level of sexual dimorphism in the deciduous crown dimensions of a selected group of South Indian population, which is sufficiently large to determine sex with an accuracy of 87.2-88% by discriminant function analysis. Hence the formula derived from the present study could be of

  3. Sexual functioning among the elderly population in Tehran, Iran.

    PubMed

    Malakouti, Seyed Kazem; Salehi, Mansour; Nojomi, Marzieh; Zandi, Taher; Eftekhar, Mehrdad

    2012-01-01

    This study aims to demonstrate the sexual functioning of elderly Iranian retirees who reside in Tehran, Iran. The participants' sexual interests are also reviewed in association with their physical and mental health status. The authors recruited 390 elders (199 men, 191 women) by convenient sampling from 4 retirement organizations in Tehran from April 2007 to October 2008. Tools for evaluation included use of a demographic questionnaire, modified Brief Index of Sexual Functioning for Women, Brief Sexual Function Inventory for Men, and the General Health Questionnaire. Sexual activity was "important/very important" in 56.6% and 17.0% of men and women, respectively (p < .005), but their satisfaction from sexual life was similar. Sexual desire and activities were more common among men than among women (p < .05). Impotency and ejaculatory problems were 40% and 33%, respectively, among the male study participants. This study indicated that having a sexual partner was the most important variable for sexual activities. This study provides a profile of sexual behaviors among elderly people in Iran and shows that although sexual decline and dysfunction are seen in both genders, both groups express satisfaction with their sexual affairs when they have a partner available.

  4. The impact of sexually abstaining groups on persistence of sexually transmitted infections in populations with ephemeral pair bonds.

    PubMed

    Maxin, D; Berec, L; Covello, M; Jessee, J; Zimmer, M

    2012-01-07

    Individuals often stop reproducing some time before they die. In this paper we compose and analyze a logistic two-sex population model in which individuals form pairs just to mate (i.e. pair bonds are ephemeral) and later move on to sexually abstaining groups. Using this model, we study the impact of sexually abstaining groups on persistence of a benign sexually transmitted infection (STI) in populations with such ephemeral pair bonds. We observe that the presence of sexually abstaining groups cannot prevent an STI from invasion or eliminate it when already present if the transition rates to the sexually abstaining groups are independent of the infection status of individuals (susceptible or infected). On the other hand, if they depend on that status, the presence of sexually abstaining groups can prevent an STI from invasion or eliminate it when present. Specifically, in the simple case of sex-independent vital parameters, this happens if the transition rate of the infected individuals to the sexually abstaining group is higher than the transition rate of the susceptible ones. These results contrast the earlier results based on assuming long-term, stable pair bonds, in which case one is capable of preventing or eliminating the disease with the same isolation rate for the susceptible and infected individuals.

  5. Molecular hyperdiversity and evolution in very large populations

    PubMed Central

    Cutter, Asher D.; Jovelin, Richard; Dey, Alivia

    2014-01-01

    The genomic density of sequence polymorphisms critically affects the sensitivity of inferences about ongoing sequence evolution, function, and demographic history. Most animal and plant genomes have relatively low densities of polymorphisms, but some species are hyperdiverse with neutral nucleotide heterozygosity exceeding 5%. Eukaryotes with extremely large populations, mimicking bacterial and viral populations, present novel opportunities for studying molecular evolution in sexually-reproducing taxa with complex development. In particular, hyperdiverse species can help answer controversial questions about the evolution of genome complexity, the limits of natural selection, modes of adaptation, and subtleties of the mutation process. However, such systems have some inherent complications and here we identify topics in need of theoretical developments. Close relatives of the model organisms Caenorhabditis elegans and Drosophila melanogaster provide known examples of hyperdiverse eukaryotes, encouraging functional dissection of resulting molecular evolutionary patterns. We recommend how best to exploit hyperdiverse populations for analysis, for example, in quantifying the impact of non-crossover recombination in genomes and for determining the identity and micro-evolutionary selective pressures on non-coding regulatory elements. PMID:23506466

  6. An epidemiological study of sexual disorders in south Indian rural population

    PubMed Central

    Sathyanarayana Rao, T. S.; Darshan, M. S.; Tandon, Abhinav

    2015-01-01

    Background: Sexuality is an important aspect of the personality of an individual and influences psychological, physical and social well-being of both men and women. It is a paradox, that in the country where ‘kamasutra’ (by Vatsyayana) took birth, there is a lack of research publications and sexuality related literature; hence the current study was conducted, to estimate the prevalence and association of sexual disorders with various socio-demographic variables, in the selected rural population. Materials and Methods: Subjects who were sexually active and fulfilled the study criteria were administered Arizona Sexual Experience Scale as screening tool for the presence of sexual problems. Those who were found to be having sexual problems were interviewed further using appropriate questionnaires. Results: 21.15% of the male subjects were diagnosed to have one (or more) sexual disorder. Prevalence of erectile dysfunction was found to be 15.77%, male hypoactive sexual desire disorder (HSDD) 2.56%; premature ejaculation was found to be prevalent in 8.76% of the male subjects. Around 14% of the female subjects were diagnosed to have female sexual disorders. Prevalence of female arousal dysfunction was found to be 6.65%, female HSDD 8.87%, female anorgasmia 5.67%, female dyspareunia 2.34% and female sexual aversion disorder was found to be prevalent in 0.37% of the female subjects. Conclusion: This study concluded that one in five males and one in seven females were suffering from one (or more) sexual disorder. Improving the training of undergraduate medical and nursing students in sexuality related issues, increasing trained individuals in sexual medicine by starting new courses, providing sex education to the general population using media and merging sexual health care with primary care, are likely to play a significant role in addressing the increasing sexual health morbidity. PMID:26124520

  7. Sexually coercive behavior in male youth: population survey of general and specific risk factors.

    PubMed

    Kjellgren, Cecilia; Priebe, Gisela; Svedin, Carl Göran; Långström, Niklas

    2010-10-01

    Little is known about risk/protective factors for sexually coercive behavior in general population youth. We used a Swedish school-based population survey of sexual attitudes and experiences (response rate 77%) and investigated literature-based variables across sexually coercive (SEX), non-sexual conduct problem (CP), and normal control (NC) participants to identify general and specific risk/protective factors for sexual coercion. Among 1,933 male youth, 101 (5.2%) reported sexual coercion (ever talked or forced somebody into genital, oral, or anal sex) (SEX), 132 (6.8%) were classified as CP, and the remaining 1,700 (87.9%) as NC. Of 29 tested variables, 25 were more common in both SEX and CP compared to NC youth, including minority ethnicity, separated parents, vocational study program, risk-taking, aggressiveness, depressive symptoms, substance abuse, sexual victimization, extensive sexual experiences, and sexual preoccupation. When compared to CP youth only, SEX youth more often followed academic study programs, used less drugs and were less risk-taking. Further, SEX more frequently than CP youth reported gender stereotypic and pro-rape attitudes, sexual preoccupation, prostitution, and friends using violent porn. Finally, in a multivariate logistic regression, academic study program, pro-rape attitudes, sexual preoccupation, and less risk-taking independently remained more strongly associated with SEX compared to CP offending. In conclusion, several sociodemographic, family, and individual risk/protective factors were common to non-sexual and sexually coercive antisocial behavior in late adolescence. However, pro-rape cognitions, and sexual preoccupation, were sexuality-related, specific risk factors. The findings could inform preventive efforts and the assessment and treatment of sexually coercive male youth.

  8. Sexual recombination in the Botrytis cinerea populations in Hungarian vineyards.

    PubMed

    Váczy, Kálmán Z; Sándor, Erzsébet; Karaffa, Levente; Fekete, Erzsébet; Fekete, Eva; Arnyasi, Mariann; Czeglédi, Levente; Kövics, György J; Druzhinina, Irina S; Kubicek, Christian P

    2008-12-01

    Botrytis cinerea (anamorph of Botryotinia fuckeliana) causes gray mold on a high number of crop plants including grapes. In this study, we investigated the genetic properties of a grape pathogenic population of B. cinerea in the area of Eger, Hungary. A total of 109 isolates from 12 areas were sampled. Based on the sequence of the beta-tubulin (tub1) locus, they all belong to group II, a phylogenetic species within B. cinerea. Seventy-four isolates were classified as transposa, with both the Flipper and Boty transposons, and 10 were classified as vacuma, lacking both transposons. The remaining isolates contained either only Flipper (13) or Boty (12). Multilocus analysis of sequences from tub1 and two other loci (elongation factor 1-alpha, tef1, and a minisatellite from the intron of an ATPase, MSB1) led to poor phylogenetic resolution of strains in individual clades. Analysis of five microsatellites (Bc2, Bc3, Bc5, Bc6, and Bc10) resulted in 55 microsatellite haplotypes within the 109 strains. No correlation was detected among individual haplotypes and the presence/absence of Flipper and/or Boty, the geographic origin, or the year of isolation. Application of the index of association, the chi-square test, and the phi test consistently indicated that the population of Hungarian isolates of B. cinerea undergoes sexual reproduction. However, the index of association test suggested the presence of some clonality, and the fixation index showed a low or occasionally moderate level of fixation in the Flipper populations. We conclude that the B. cinerea populations in Hungary consist of a strongly recombining group II phylogenetic species.

  9. Sexuality after breast cancer: cultural specificities of Tunisian population

    PubMed Central

    Leila, Mnif; Nada, Charfi; Kais, Chaabene; Jawaher, Masmoudi

    2016-01-01

    Introduction Women’s sexuality may be particularly affected after breast cancer. The objectives of this study were to evaluate the changes in sexual life after treatment of breast cancer in Tunisian women and to identify the influence of demographic and clinical factors on sexuality. Methods We recruited 50 patients who were in remission for at least 3 months after initial treatment of breast cancer. Sexuality and body image were evaluated using the Arabic version of the specific scale of breast cancer QLQ-BR23. Screening for emotional disorders has been done with the Arabic version of HAD scale (Hospital anxiety and depression scale). Results Patients had poor sexual functioning and sexual satisfaction and the mean scores were respectively 45.3% and 43.9%. Only menopausal status and sexual difficulties in the partner was significantly related to poorer sexual satisfaction (p respectively 0.018 and 0.014). According to the HAD scale, 42% of patients had anxiety and 44% had depression. The sexual satisfaction was statistically associated with the presence of anxiety symptoms (p=0.0003). Conclusion Results suggest that the psychological side and the sexual difficulties in partner are the most important factors that appear to be involved in sexual satisfaction of Tunisian women after breast cancer. So, those factors need to be taken into account in therapeutic process and psychological counseling to maintain and enhance patient’s psychological well-being. PMID:28154709

  10. Infection dynamics in coexisting sexual and asexual host populations: support for the Red Queen hypothesis.

    PubMed

    Vergara, Daniela; Jokela, Jukka; Lively, Curtis M

    2014-08-01

    The persistence of sexual reproduction is a classic problem in evolutionary biology. The problem stems from the fact that, all else equal, asexual lineages should rapidly replace coexisting sexual individuals due to the cost of producing males in sexual populations. One possible countervailing advantage to sexual reproduction is that, on average, outcrossed offspring are more resistant than common clones to coevolving parasites, as predicted under the Red Queen hypothesis. In this study, we evaluated the prevalence of infection by a sterilizing trematode (Microphallus sp.) in a natural population of freshwater snails that was composed of both sexual and asexual individuals (Potamopyrgus antipodarum). More specifically, we compared the frequency of infection in sexual and asexual individuals over a 5-year period at four sites at a natural glacial lake (Lake Alexandrina, South Island, New Zealand). We found that at most sites and over most years, the sexual population was less infected than the coexisting asexual population. Moreover, the frequency of uninfected sexual females was periodically greater than two times the frequency of uninfected asexual females. These results give clear support for a fluctuating parasite-mediated advantage to sexual reproduction in a natural population.

  11. A population of sexual Daphnia pulex resists invasion by asexual clones.

    PubMed

    Innes, David J; Ginn, Michael

    2014-08-07

    Asexual reproduction avoids the costs associated with sex, predicting that invading asexual clones can quickly replace sexual populations. Daphnia pulex populations in the Great Lakes area are predominately asexual, but the elimination of sexual populations by invading clones is poorly understood. Asexual clones were detected at low frequency in one rare sexual population in 1995, with some increase in frequency during 2003 and 2004. However, these clones remained at low frequency during further yearly sampling (2005-2013) with no evidence that the resident sexual population was in danger of elimination. There was evidence for hybridization between rare males produced by asexual clones and sexual females with the potential to produce new asexual genotypes and spread the genetic factors for asexuality. In a short-term laboratory competition experiment, the two most common asexual clones did not increase in frequency relative to a genetically diverse sexual population due in part to a greater investment in diapausing eggs that trades-off current population growth for increased contribution to the egg bank. Our results suggest that a successful invasion can be prolonged, requiring a combination of clonal genotypes with high fitness, persistence of clones in the egg bank and negative factors affecting the sexual population such as inbreeding depression resulting from population bottlenecks.

  12. A population of sexual Daphnia pulex resists invasion by asexual clones

    PubMed Central

    Innes, David J.; Ginn, Michael

    2014-01-01

    Asexual reproduction avoids the costs associated with sex, predicting that invading asexual clones can quickly replace sexual populations. Daphnia pulex populations in the Great Lakes area are predominately asexual, but the elimination of sexual populations by invading clones is poorly understood. Asexual clones were detected at low frequency in one rare sexual population in 1995, with some increase in frequency during 2003 and 2004. However, these clones remained at low frequency during further yearly sampling (2005–2013) with no evidence that the resident sexual population was in danger of elimination. There was evidence for hybridization between rare males produced by asexual clones and sexual females with the potential to produce new asexual genotypes and spread the genetic factors for asexuality. In a short-term laboratory competition experiment, the two most common asexual clones did not increase in frequency relative to a genetically diverse sexual population due in part to a greater investment in diapausing eggs that trades-off current population growth for increased contribution to the egg bank. Our results suggest that a successful invasion can be prolonged, requiring a combination of clonal genotypes with high fitness, persistence of clones in the egg bank and negative factors affecting the sexual population such as inbreeding depression resulting from population bottlenecks. PMID:24943366

  13. An exploratory investigation of sexual health screening in the first 12 weeks of case management in populations with severe mental illness.

    PubMed

    Corbett, Rebecca; Elsom, Stephen; Sands, Natisha; Prematunga, Roshani

    2017-04-01

    The sexual health of people with mental illness is commonly overlooked, neglected or inadequately addressed in mental health care, despite evidence showing that people with severe mental illness are more vulnerable to sexually transmitted infections (including HIV), sexual side-effects, and sexual dysfunction than the general population. This article reports a study that investigated sexual health screening in five community mental health clinics within a large a regional health service in Victoria, Australia. The aim of the study was to examine the extent to which sexual health screening is currently undertaken on newly admitted case-managed consumers, and to identify the types of screening undertaken. An exploratory design using retrospective file audit was used in the study. A total of 186 medical records met the study inclusion criteria. The study found that less than 40% of consumers were provided with sexual health screening during their first 12 weeks of case management. The study also found that sexual side-effects, issues of fertility, sexual self-esteem, safe sexual practices, and sexual dysfunction were rarely screened for. Poor sexual health screening has implications for the safety and quality of mental health care and requires targeted research to improve understandings and approaches to care.

  14. The genetic architecture of sexually selected traits in two natural populations of Drosophila montana

    PubMed Central

    Veltsos, P; Gregson, E; Morrissey, B; Slate, J; Hoikkala, A; Butlin, R K; Ritchie, M G

    2015-01-01

    We investigated the genetic architecture of courtship song and cuticular hydrocarbon traits in two phygenetically distinct populations of Drosophila montana. To study natural variation in these two important traits, we analysed within-population crosses among individuals sampled from the wild. Hence, the genetic variation analysed should represent that available for natural and sexual selection to act upon. In contrast to previous between-population crosses in this species, no major quantitative trait loci (QTLs) were detected, perhaps because the between-population QTLs were due to fixed differences between the populations. Partitioning the trait variation to chromosomes suggested a broadly polygenic genetic architecture of within-population variation, although some chromosomes explained more variation in one population compared with the other. Studies of natural variation provide an important contrast to crosses between species or divergent lines, but our analysis highlights recent concerns that segregating variation within populations for important quantitative ecological traits may largely consist of small effect alleles, difficult to detect with studies of moderate power. PMID:26198076

  15. The genetic architecture of sexually selected traits in two natural populations of Drosophila montana.

    PubMed

    Veltsos, P; Gregson, E; Morrissey, B; Slate, J; Hoikkala, A; Butlin, R K; Ritchie, M G

    2015-12-01

    We investigated the genetic architecture of courtship song and cuticular hydrocarbon traits in two phygenetically distinct populations of Drosophila montana. To study natural variation in these two important traits, we analysed within-population crosses among individuals sampled from the wild. Hence, the genetic variation analysed should represent that available for natural and sexual selection to act upon. In contrast to previous between-population crosses in this species, no major quantitative trait loci (QTLs) were detected, perhaps because the between-population QTLs were due to fixed differences between the populations. Partitioning the trait variation to chromosomes suggested a broadly polygenic genetic architecture of within-population variation, although some chromosomes explained more variation in one population compared with the other. Studies of natural variation provide an important contrast to crosses between species or divergent lines, but our analysis highlights recent concerns that segregating variation within populations for important quantitative ecological traits may largely consist of small effect alleles, difficult to detect with studies of moderate power.

  16. Sexual violence among host and refugee population in Djohong District, Eastern Cameroon.

    PubMed

    Parmar, Parveen; Agrawal, Pooja; Greenough, P Gregg; Goyal, Ravi; Kayden, Stephanie

    2012-01-01

    The following is a population-based survey of the Central African Republic (CAR) female refugee population displaced to rural Djohong District of Eastern Cameroon and associated female Cameroonian host population to characterise the prevalence and circumstances of sexual violence. A population-based, multistage, random cluster survey of 600 female heads of household was conducted during March 2010. Women heads of household were asked about demographics, household economy and assets, level of education and sexual violence experienced by the respondent only. The respondents were asked to describe the circumstances of their recent assault. The lifetime prevalence of sexual violence among Djohong district female heads of household is 35.2% (95% CI 28.7-42.2). Among heads of household who reported a lifetime incident of sexual violence, 64.0% (95% CI 54.3-72.5) suffered sexual violence perpetrated by their husband or partner. Among the host population, 3.9% (95% CI 1.4-10.5) reported sexual violence by armed groups compared to 39.0% (95% CI 25.6-54.2) of female refugee heads of household. Women who knew how to add and subtract were less likely to report sexual violence during their lifetime (OR 0.16, 95% CI 0.08-0.34). Sexual violence is common among refugees and host population in Eastern Cameroon. Most often, perpetrators are partners/husbands or armed groups.

  17. Prevalence and denial of sexual abuse in a male psychiatric inpatient population.

    PubMed

    Lab, Damon D; Moore, Estelle

    2005-08-01

    While the link between sexual abuse and psychiatric morbidity is well established, there are only a few studies that have investigated the prevalence of sexual abuse in male psychiatric populations and these studies have typically employed designs that ignore methodological issues specific to male sexual abuse. The present study aims to contribute to this research using as methodologically sound approach as possible. Seventy-four male inpatients were interviewed using a questionnaire (J. N. Briere, 1992) about childhood sexual experiences. Approximately one third reported incidents that met this study's criteria for sexual abuse. Many of these men did not label such experiences as "sexual abuse." The results suggest that mental health professionals need to be aware that many of their male patients may have a history of sexual abuse and that potential minimization or denial of it is a barrier to disclosure.

  18. Coalescence and genetic diversity in sexual populations under selection.

    PubMed

    Neher, Richard A; Kessinger, Taylor A; Shraiman, Boris I

    2013-09-24

    In sexual populations, selection operates neither on the whole genome, which is repeatedly taken apart and reassembled by recombination, nor on individual alleles that are tightly linked to the chromosomal neighborhood. The resulting interference between linked alleles reduces the efficiency of selection and distorts patterns of genetic diversity. Inference of evolutionary history from diversity shaped by linked selection requires an understanding of these patterns. Here, we present a simple but powerful scaling analysis identifying the unit of selection as the genomic "linkage block" with a characteristic length, , determined in a self-consistent manner by the condition that the rate of recombination within the block is comparable to the fitness differences between different alleles of the block. We find that an asexual model with the strength of selection tuned to that of the linkage block provides an excellent description of genetic diversity and the site frequency spectra compared with computer simulations. This linkage block approximation is accurate for the entire spectrum of strength of selection and is particularly powerful in scenarios with many weakly selected loci. The latter limit allows us to characterize coalescence, genetic diversity, and the speed of adaptation in the infinitesimal model of quantitative genetics.

  19. An ephemeral sexual population of Phytophthora infestans in the Northeastern United States and Canada.

    PubMed

    Danies, Giovanna; Myers, Kevin; Mideros, María F; Restrepo, Silvia; Martin, Frank N; Cooke, David E L; Smart, Christine D; Ristaino, Jean B; Seaman, Abby J; Gugino, Beth K; Grünwald, Niklaus J; Fry, William E

    2014-01-01

    Phytophthora infestans, the causal agent of late blight disease, has been reported in North America since the mid-nineteenth century. In the United States the lack of or very limited sexual reproduction has resulted in largely clonal populations of P. infestans. In 2010 and 2011, but not in 2012 or 2013, 20 rare and diverse genotypes of P. infestans were detected in a region that centered around central New York State. The ratio of A1 to A2 mating types among these genotypes was close to the 50∶50 ratio expected for sexual recombination. These genotypes were diverse at the glucose-6-phosphate isomerase locus, differed in their microsatellite profiles, showed different banding patterns in a restriction fragment length polymorphism assay using a moderately repetitive and highly polymorphic probe (RG57), were polymorphic for four different nuclear genes and differed in their sensitivity to the systemic fungicide mefenoxam. The null hypothesis of linkage equilibrium was not rejected, which suggests the population could be sexual. These new genotypes were monomorphic in their mitochondrial haplotype that was the same as US-22. Through parentage exclusion testing using microsatellite data and sequences of four nuclear genes, recent dominant lineages US-8, US-11, US-23, and US-24 were excluded as possible parents for these genotypes. Further analyses indicated that US-22 could not be eliminated as a possible parent for 14 of the 20 genotypes. We conclude that US-22 could be a parent of some, but not all, of the new genotypes found in 2010 and 2011. There were at least two other parents for this population and the genotypic characteristics of the other parents were identified.

  20. Implementation and Evaluation of a Values Clarification Activity for a Large Undergraduate Human Sexuality Course

    ERIC Educational Resources Information Center

    Lederer, Alyssa M.

    2016-01-01

    Values clarification is an important tool that helps individuals to clarify their beliefs about sexuality-related issues. This lesson plan provides instructions for a 1-hour values clarification activity for a large undergraduate human sexuality course that serves as an introduction to course content and tone, stimulates students' initial thinking…

  1. Sexually Transmitted Diseases and Risk Behaviors among California Farmworkers: Results from a Population-Based Survey

    ERIC Educational Resources Information Center

    Brammeier, Monique; Chow, Joan M.; Samuel, Michael C.; Organista, Kurt C.; Miller, Jamie; Bolan, Gail

    2008-01-01

    Context: The prevalence of sexually transmitted diseases and associated risk behaviors among California farmworkers is not well described. Purpose: To estimate the prevalence of sexually transmitted diseases (STDs) and associated risk behaviors among California farmworkers. Methods: Cross-sectional analysis of population-based survey data from 6…

  2. Patterns of Vaginal, Oral, and Anal Sexual Intercourse in an Urban Seventh-Grade Population

    ERIC Educational Resources Information Center

    Markham, Christine M.; Peskin, Melissa Fleschler; Addy, Robert C.; Baumler, Elizabeth R.; Tortolero, Susan R.

    2009-01-01

    Background: This study examines the prevalence of vaginal, oral, and anal intercourse among a population of urban, public middle school students, the characteristics of early sexual initiators, and the sequence of sexual initiation. Such data are limited for early adolescents. Methods: A total of 1279 seventh-grade students (57.3% female, 43.6%…

  3. Social Support Networks Among Diverse Sexual Minority Populations

    PubMed Central

    Frost, David M.; Meyer, Ilan H.; Schwartz, Sharon

    2016-01-01

    This paper reports a study of the function and composition of social support networks among diverse lesbian, gay and bisexual (LGB) men and women (n = 396) in comparison to their heterosexual peers (n = 128). Data were collected using a structured social support network matrix in a community sample recruited in New York City. Our findings show that gay and bisexual men may rely on “chosen families” within LGBT communities more so than lesbian and bisexual women. Both heterosexuals and LGBs relied less on family and more on other people (e.g., friends, co-workers) for everyday social support (e.g., recreational and social activities, talking about problems). Providers of everyday social support were most often of the same sexual orientation and race/ethnicity as participants. In seeking major support (e.g., borrowing large sums of money), heterosexual men and women along with lesbian and bisexual women relied primarily on their families, but gay and bisexual men relied primarily on other LGB individuals. Racial/ethnic minority LGBs relied on LGB similar others at the same rate at White LGBs but, notably, racial/ethnic minority LGBs reported receiving fewer dimensions of support. PMID:26752447

  4. Sexual conflict and the gender load: correlated evolution between population fitness and sexual dimorphism in seed beetles

    PubMed Central

    Arnqvist, Göran; Tuda, Midori

    2010-01-01

    Although males and females share much of the same genome, selection is often distinct in the two sexes. Sexually antagonistic loci will in theory cause a gender load in populations, because sex-specific selection on a given trait in one sex will compromise the adaptive evolution of the same trait in the other sex. However, it is currently not clear whether such intralocus sexual conflict (ISC) represents a transient evolutionary state, where conflict is rapidly resolved by the evolution of sexual dimorphism (SD), or whether it is a more chronic impediment to adaptation. All else being equal, ISC should manifest itself as correlated evolution between population fitness and SD in traits expressed in both sexes. However, comparative tests of this prediction are problematic and have been unfeasible. Here, we assess the effects of ISC by comparing fitness and SD across distinct laboratory populations of seed beetles that should be well adapted to a shared environment. We show that SD in juvenile development time, a key life-history trait with a history of sexually antagonistic selection in this model system, is positively related to fitness. This effect is due to a correlated evolution between population fitness and development time that is positive in females but negative in males. Loosening the genetic bind between the sexes has evidently allowed the sexes to approach their distinct adaptive peaks. PMID:20031994

  5. Sexual conflict and the gender load: correlated evolution between population fitness and sexual dimorphism in seed beetles.

    PubMed

    Arnqvist, Göran; Tuda, Midori

    2010-05-07

    Although males and females share much of the same genome, selection is often distinct in the two sexes. Sexually antagonistic loci will in theory cause a gender load in populations, because sex-specific selection on a given trait in one sex will compromise the adaptive evolution of the same trait in the other sex. However, it is currently not clear whether such intralocus sexual conflict (ISC) represents a transient evolutionary state, where conflict is rapidly resolved by the evolution of sexual dimorphism (SD), or whether it is a more chronic impediment to adaptation. All else being equal, ISC should manifest itself as correlated evolution between population fitness and SD in traits expressed in both sexes. However, comparative tests of this prediction are problematic and have been unfeasible. Here, we assess the effects of ISC by comparing fitness and SD across distinct laboratory populations of seed beetles that should be well adapted to a shared environment. We show that SD in juvenile development time, a key life-history trait with a history of sexually antagonistic selection in this model system, is positively related to fitness. This effect is due to a correlated evolution between population fitness and development time that is positive in females but negative in males. Loosening the genetic bind between the sexes has evidently allowed the sexes to approach their distinct adaptive peaks.

  6. Sexual Segregation in Juvenile New Zealand Sea Lion Foraging Ranges: Implications for Intraspecific Competition, Population Dynamics and Conservation

    PubMed Central

    Leung, Elaine S.; Chilvers, B. Louise; Nakagawa, Shinichi; Moore, Antoni B.; Robertson, Bruce C.

    2012-01-01

    Sexual segregation (sex differences in spatial organisation and resource use) is observed in a large range of taxa. Investigating causes for sexual segregation is vital for understanding population dynamics and has important conservation implications, as sex differences in foraging ecology may affect vulnerability to area-specific human activities. Although behavioural ecologists have proposed numerous hypotheses for this phenomenon, the underlying causes of sexual segregation are poorly understood. We examined the size-dimorphism and niche divergence hypotheses as potential explanations for sexual segregation in the New Zealand (NZ) sea lion (Phocarctos hookeri), a nationally critical, declining species impacted by trawl fisheries. We used satellite telemetry and linear mixed effects models to investigate sex differences in the foraging ranges of juvenile NZ sea lions. Male trip distances and durations were almost twice as long as female trips, with males foraging over the Auckland Island shelf and in further locations than females. Sex was the most important variable in trip distance, maximum distance travelled from study site, foraging cycle duration and percent time at sea whereas mass and age had small effects on these characteristics. Our findings support the predictions of the niche divergence hypothesis, which suggests that sexual segregation acts to decrease intraspecific resource competition. As a consequence of sexual segregation in foraging ranges, female foraging grounds had proportionally double the overlap with fisheries operations than males. This distribution exposes female juvenile NZ sea lions to a greater risk of resource competition and bycatch from fisheries than males, which can result in higher female mortality. Such sex-biased mortality could impact population dynamics, because female population decline can lead to decreased population fecundity. Thus, effective conservation and management strategies must take into account sex differences

  7. Sexual segregation in juvenile New Zealand sea lion foraging ranges: implications for intraspecific competition, population dynamics and conservation.

    PubMed

    Leung, Elaine S; Chilvers, B Louise; Nakagawa, Shinichi; Moore, Antoni B; Robertson, Bruce C

    2012-01-01

    Sexual segregation (sex differences in spatial organisation and resource use) is observed in a large range of taxa. Investigating causes for sexual segregation is vital for understanding population dynamics and has important conservation implications, as sex differences in foraging ecology may affect vulnerability to area-specific human activities. Although behavioural ecologists have proposed numerous hypotheses for this phenomenon, the underlying causes of sexual segregation are poorly understood. We examined the size-dimorphism and niche divergence hypotheses as potential explanations for sexual segregation in the New Zealand (NZ) sea lion (Phocarctos hookeri), a nationally critical, declining species impacted by trawl fisheries. We used satellite telemetry and linear mixed effects models to investigate sex differences in the foraging ranges of juvenile NZ sea lions. Male trip distances and durations were almost twice as long as female trips, with males foraging over the Auckland Island shelf and in further locations than females. Sex was the most important variable in trip distance, maximum distance travelled from study site, foraging cycle duration and percent time at sea whereas mass and age had small effects on these characteristics. Our findings support the predictions of the niche divergence hypothesis, which suggests that sexual segregation acts to decrease intraspecific resource competition. As a consequence of sexual segregation in foraging ranges, female foraging grounds had proportionally double the overlap with fisheries operations than males. This distribution exposes female juvenile NZ sea lions to a greater risk of resource competition and bycatch from fisheries than males, which can result in higher female mortality. Such sex-biased mortality could impact population dynamics, because female population decline can lead to decreased population fecundity. Thus, effective conservation and management strategies must take into account sex differences

  8. Sexual dimorphism is associated with population fitness in the seed beetle Callosobruchus maculatus.

    PubMed

    Rankin, Daniel J; Arnqvist, Göran

    2008-03-01

    The population consequences of sexual selection remain empirically unexplored. Comparative studies, involving extinction risk, have yielded different results as to the effect of sexual selection on population densities make contrasting predictions. Here, we investigate the relationship between sexual dimorphism (SD) and population productivity in the seed beetle Callosobruchus maculatus, using 13 populations that have evolved in isolation. Geometric morphometric methods and image analysis are employed to form integrative measures of sexual dimorphism, composed of variation in weight, size, body shape, and pigmentation. We found a positive relationship between SD and adult fitness (net adult offspring production) across our study populations, but failed to find any association between SD and juvenile fitness (egg-to-adult survival). Several mechanisms may have contributed to the pattern found, and variance in sexual selection regimes across populations, either in female choice for "good genes" or in the magnitude of direct benefits provided by their mates, would tend to produce the pattern seen. However, our results suggest that evolutionary constraints in the form of intralocus sexual conflict may have been the major generator of the relationship seen between SD and population fitness.

  9. Evaluation of the potential for sexual reproduction in field populations of Cercospora beticola from USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cercospora leaf spot, caused by the hemibiotrophic fungal pathogen Cercospora beticola, is the most economically damaging foliar disease of sugarbeet worldwide. Although most C. beticola populations display characteristics reminiscent of sexual recombination, no teleomorph has been described. To ass...

  10. Population-based sexual behavior surveys in China: Liuzhou compared with other prefectural cities.

    PubMed

    Huang, Yingying; Abler, Laurie; Pan, Suiming; Henderson, Gail E; Wang, Xin; Yao, Xingliang; Parish, William L

    2014-02-01

    Sexual behaviors in China are rapidly changing; simultaneously, sexually transmitted infections (STI)/HIV prevalence is increasing in the general population. To investigate these major shifts, we examined sexual behaviors and self-reported STI in one prefectural city in southern China, Liuzhou, and compared it to other prefectural cities throughout China. We used adults age 18-39 from two sets of population-based surveys that paralleled each other in both content and method. The first set was the Liuzhou survey conducted in 2008 (n = 398). The second set consisted of two national surveys collected in 2006 and 2010 (n = 2,186). Liuzhou respondents reported more active social and sexual behaviors than their national counterparts, including more socializing, dancing, drinking excessively, sexual activity among never married men and women, purchasing commercial sex among men, one-night stands among men, multiple sexual partnerships and self-reported STI among both men and women. Women in Liuzhou reported greater sexual risk behavior than their national counterparts, although overall they reported less than their male counterparts; they were also more likely to have had an abortion than women in other prefectural cities. Our findings provide a comprehensive overview of the sexual context of Liuzhou among the general population, which may help explain the greater STI/HIV prevalence in Liuzhou.

  11. Population-based sexual behavior surveys in China: Liuzhou compared with other prefectural cities

    PubMed Central

    Yingying, Huang; Abler, Laurie; Suiming, Pan; Henderson, Gail E.; Xin, Wang; Xingliang, Yao; Parish, William L.

    2013-01-01

    Sexual behaviors in China are rapidly changing; simultaneously, STI/HIV prevalence is increasing in the general population. To investigate these major shifts, we examined sexual behaviors and self-reported sexually transmitted infections (STI) in one prefectural city in southern China, Liuzhou, and compared it to other prefectural cities throughout China. We used adults age 18-39 from two sets of population-based surveys that paralleled each other in both content and method. The first set was the Liuzhou survey conducted in 2008 (n=398). The second set consisted of two national surveys collected in 2006 and 2010 (n=2186). Liuzhou respondents reported more active social and sexual behaviors than their national counterparts, including more socializing, dancing, drinking excessively, sexual activity among never married men and women, purchasing commercial sex among men, one-night stands among men, multiple sexual partnerships and self-reported STI among both men and women. Women in Liuzhou reported greater sexual risk behavior than their national counterparts, although overall they reported less than their male counterparts; they were also more likely to have had an abortion than women in other prefectural cities. Our findings provide a comprehensive overview of the sexual context of Liuzhou among the general population, which may help explain the greater STI/HIV prevalence in Liuzhou. PMID:24174289

  12. Stochastic modeling in biological populations with sexual reproduction through branching models: application to Coho salmon populations.

    PubMed

    Molina, Manuel; Mota, Manuel; Ramos, Alfonso

    2014-12-01

    The motivation behind this research is to develop appropriate mathematical models to describe the demographic dynamics of animal populations with sexual reproduction. We introduce a new class of two-sex branching models where several mating strategies between females and males and a variety of possibilities for the process of reproduction are taken into account. Unlike other classes of two-sex models which assume that mating and reproduction are influenced by the number of couples in the population, we now consider the most realistic case where both biological processes are affected by the numbers of females and males in the population, which may differ. Under a general parametric setting, we deal with inferential questions about the main parameters affecting the reproduction process. By considering the observation over time of the numbers of females and males up to when a certain pre-set generation is reached, we derive Bayes estimators for such parameters. With the purpose of determining highest posterior density credibility sets, we also propose a computational algorithm. As illustration, we include an application to Coho salmon populations.

  13. Are depression and poor sexual health neglected comorbidities? Evidence from a population sample

    PubMed Central

    Field, Nigel; Prah, Philip; Mercer, Catherine H; Rait, Greta; King, Michael; Cassell, Jackie A; Heath, Laura; Mitchell, Kirstin R; Clifton, Soazig; Datta, Jessica; Wellings, Kaye; Johnson, Anne M; Sonnenberg, Pam

    2016-01-01

    Objective To examine associations between sexual behaviour, sexual function and sexual health service use of individuals with depression in the British general population, to inform primary care and specialist services. Setting British general population. Participants 15 162 men and women aged 16–74 years were interviewed for the third National Survey of Sexual Attitudes and Lifestyles (Natsal-3), undertaken in 2010–2012. Using age-adjusted ORs (aAOR), relative to a comparator group reporting no treatment or symptoms, we compared the sexual health of those reporting treatment for depression in the past year. Outcome measures Sexual risk behaviour, sexual function, sexual satisfaction and sexual health service use. Results 1331 participants reported treatment for depression (5.2% men; 11.8% women). Relative to the comparator group, treatment for depression was associated with reporting 2 or more sexual partners without condoms (men aAOR 2.07 (95% CI 1.38 to 3.10); women 2.22 (1.68 to 2.92)), and concurrent partnerships (men 1.80 (1.18 to 2.76); women 2.06 (1.48 to 2.88)), in the past year. Those reporting depression treatment were more likely to be dissatisfied with their sex lives (men 2.32 (1.74 to 3.11); women 2.30 (1.89 to 2.79)), and to score in the lowest quintile on the Natsal-sexual function measure. They were also more likely to report a recent chlamydia test (men 1.92 (1.15 to 3.20)); women (1.27 (1.01 to 1.60)), and to have sought help regarding their sex life from a healthcare professional (men 2.92 (1.98 to 4.30); women (2.36 (1.83 to 3.04)), most commonly from a family doctor. Women only were more likely to report attending a sexual health clinic (1.91 (1.42 to 2.58)) and use of emergency contraception (1.98 (1.23 to 3.19)). Associations were broadly similar for individuals with depressive symptoms but not reporting treatment. Conclusions Depression, measured by reported treatment, was strongly associated with sexual risk behaviours, reduced

  14. Genetic differences among populations in sexual dimorphism: evidence for selection on males in a dioecious plant

    PubMed Central

    YU, Q.; ELLEN, E. D.; WADE, M. J.; DELPH, L. F.

    2011-01-01

    Genetic variation among populations in the degree of sexual dimorphism may be a consequence of selection on one or both sexes. We analysed genetic parameters from crosses involving three populations of the dioecious plant Silene latifolia, which exhibits sexual dimorphism in flower size, to determine whether population differentiation was a result of selection on one or both sexes. We took the novel approach of comparing the ratio of population differentiation of a quantitative trait (QST) to that of neutral genetic markers (FST) for males vs. females. We attributed 72.6% of calyx width variation in males to differences among populations vs. only 6.9% in females. The QST/FST ratio was 4.2 for males vs. 0.4 for females, suggesting that selection on males is responsible for differentiation among populations in calyx width and its degree of sexual dimorphism. This selection may be indirect via genetic correlations with other morphological and physiological traits. PMID:21401772

  15. Right to sexual and reproductive health in new population policies of Iran.

    PubMed

    Kokabisaghi, Fatemeh

    2017-02-24

    Sexual and reproductive health services in Iran are influenced by population policies. Willingness of Iranian policy makers to control the population's growth rate resulted in the provision of countrywide family planning services and contraceptives from 1990 to 2013. Now policy makers favour population growth because of a statistically significant decline in the fertility rate and ageing of the population. New population policies contain incentives for higher fertility and limitations on family planning services. Some elements of these policies contradict standards of international human rights treaties including prohibition against retrogressive measures and limitations on sexual and reproductive health services. These policies may jeopardize individual and public health. Iran should immediately revoke these laws and policies and progressively improve people's enjoyment of their right to sexual and reproductive health. The country's population policies should focus on encouraging people to have higher fertility by providing financial and social support to parents and future children.

  16. Childhood sexual abuse by representatives of the Roman Catholic Church: a prevalence estimate among the Dutch population.

    PubMed

    Langeland, Willemien; Hoogendoorn, Adriaan W; Mager, Daniel; Smit, Jan H; Draijer, Nel

    2015-08-01

    Estimates of the extent of childhood sexual abuse (CSA) within in the Roman Catholic Church (RCC) in the general population are difficult to find. The independent Commission of Inquiry into sexual abuse of minors in the RCC in the Netherlands collected population-based data to estimate its prevalence. A large random online population sample was surveyed using a two-phase stratified sampling procedure. In Phase 1, 34,267 subjects aged 40 years and older were screened for childhood exposure to sexual abuse by non-family members, a history of institutionalization and a Roman Catholic upbringing. In Phase 2, a stratified subset of 2,462 subjects was assessed to obtain more detailed target information about sexual abuse reports within the RCC. We employed multiple imputation for the estimation of RCC CSA in the original Phase 1 sample. The prevalence of non-familial CSA in general (14.0%) was higher among women (17.2%) than among men (10.6%). The prevalence of CSA within the Dutch RCC (1.7%) was higher among men (2.7%) than among women (0.7%). As expected, older subjects reported more often CSA in the RCC than their younger counterparts. Respondents who stayed for some time in RCC run institutions for education or child protection had a higher risk to report sexual abuse. Although sexual abuse of minors by representatives of the RCC was a structural problem during a period that the Church was highly influential in the Netherlands, the estimated prevalence of the phenomenon is only a fraction of the prevalence rate of non-familial CSA.

  17. Sexual Behaviors among Adults in Puerto Rico: A Population-Based Study

    PubMed Central

    Ortiz, Ana Patricia; Soto-Salgado, Marievelisse; Suárez, Erick; Santos-Ortiz, María del Carmen; Tortolero-Luna, Guillermo; Pérez, Cynthia M.

    2012-01-01

    Introduction Given changes in sexual behaviors and norms in the United States, there is a need for current and representative data on sexual behaviors with particular interest in gender, age, and racial/ethnic group differences. Aim Given the limited data for Hispanics and for Puerto Rico (PR), we described patterns of sexual behaviors and characteristics among a sexually active sample (n = 1,575) of adults aged 21–64 years in PR. Main Outcome Measures The main outcome measures for this study are sexual behaviors including age at sexual initiation, number of sexual partners, vaginal and anal intercourse, and oral sex, among others. Methods Data from a population-based cross-sectional study in PR (2005–2008) was analyzed. The prevalence of sexual behaviors and characteristics was described by age-group and gender during the lifetime and in the past 12 months. Results Overall, 96.8%, 81.6%, and 60.9% of participants had ever engaged in vaginal, oral and anal sex, respectively, whereas 23.7% were seropositive to any of the sexually transmitted infections under study. Sexual initiation ≤15 years was reported by 37.8% of men and 21.4% of women; whereas 47.9% of men and 13.2% of women reported to have had ≥7 sexual partners in their lifetime. Approximately, 3% of women and 6% of men reported same-sex sexual practices, while history of forced sexual relations was reported by 9.6% of women and 2.5% of men. Sexual initiation ≤15 years was more common among individuals aged 21–34 years (41.4% men and 33.6% women) as compared with older cohorts. Although having had ≥7 sexual partners over a lifetime among men was similar across age groups, this behavior decreased in older women cohorts. In both genders, the prevalence of oral and anal sex was also lower in the older age cohorts. Conclusion This study provides essential information than can help health professionals understand the sexual practices and needs of the population of PR. PMID:21676177

  18. [Analysis of Sexual Strategies Theory in the Spanish population].

    PubMed

    Yela, Carlos

    2012-02-01

    The aim of this study was to test some of the main hypotheses derived from Buss' Sexual Strategies Theory on a representative Spanish sample. These hypotheses refer to the different strategies men and woman seem to adopt when they want to engage in a short-term sexual relationship (fling), or in a long-term one (loving relationship). (The technical term "strategies", unlike its equivalent in everyday language, is not meant to imply something necessarily planned or conscious). Data was obtained by self-report from a representative sample of 1949 Spanish people. Almost all the results verify the working hypotheses, conferring some empirical support on the theory from which they were deduced, within an evolutionary Social Psychology paradigm. In any case, it is argued that socialization approaches ("double moral" and the social construction of gender role and sexual identity) can also explain most of the differences obtained, in perfect compatibility with biological perspectives.

  19. Evolution of increased phenotypic diversity enhances population performance by reducing sexual harassment in damselflies.

    PubMed

    Takahashi, Yuma; Kagawa, Kotaro; Svensson, Erik I; Kawata, Masakado

    2014-07-18

    The effect of evolutionary changes in traits and phenotypic/genetic diversity on ecological dynamics has received much theoretical attention; however, the mechanisms and ecological consequences are usually unknown. Female-limited colour polymorphism in damselflies is a counter-adaptation to male mating harassment, and thus, is expected to alter population dynamics through relaxing sexual conflict. Here we show the side effect of the evolution of female morph diversity on population performance (for example, population productivity and sustainability) in damselflies. Our theoretical model incorporating key features of the sexual interaction predicts that the evolution of increased phenotypic diversity will reduce overall fitness costs to females from sexual conflict, which in turn will increase productivity, density and stability of a population. Field data and mesocosm experiments support these model predictions. Our study suggests that increased phenotypic diversity can enhance population performance that can potentially reduce extinction rates and thereby influence macroevolutionary processes.

  20. Germline Selection: Population Genetic Aspects of the Sexual/Asexual Life Cycle

    PubMed Central

    Hastings, I. M.

    1991-01-01

    Population geneticists make a distinction between sexual and asexual organisms depending on whether individuals inherit genes from one or two parents. When individual genes are considered, this distinction becomes less satisfactory for multicellular sexual organisms. Individual genes pass through numerous asexual mitotic cell divisions in the germline prior to meiosis and sexual recombination. The processes of mitotic mutation, mitotic crossing over, and mitotic gene conversion create genotypic diversity between diploid cells in the germline. Genes expressed in the germline whose products affect cell viability (such as many ``housekeeping'' enzymes) may be subjected to natural selection acting on this variability resulting in a non-Mendelian output of gametes. Such genes will be governed by the population genetics of the sexual/asexual life cycle rather than the conventional sexual/Mendelian life cycle. A model is developed to investigate some properties of the sexual/asexual life cycle. When appropriate parameter values were included in the model, it was found that mutation rates per locus per gamete may vary by a factor of up to 100 if selection acts in the germline. Sexual/asexual populations appear able to evolve to a genotype of higher fitness despite intervening genotypes of lower fitness, reducing the problems of underdominance and Wright's adaptive landscape encountered by purely sexual populations. As might be expected this ability is chiefly determined by the number of asexual mitotic cell divisions within the germline. The evolutionary consequences of ``housekeeping'' loci being governed by the dynamics of the sexual/asexual life cycle are considered. PMID:1783297

  1. Sexual Dimorphism and Population Differences in Structural Properties of Barn Swallow (Hirundo rustica) Wing and Tail Feathers.

    PubMed

    Pap, Péter L; Osváth, Gergely; Aparicio, José Miguel; Bărbos, Lőrinc; Matyjasiak, Piotr; Rubolini, Diego; Saino, Nicola; Vágási, Csongor I; Vincze, Orsolya; Møller, Anders Pape

    2015-01-01

    Sexual selection and aerodynamic forces affecting structural properties of the flight feathers of birds are poorly understood. Here, we compared the structural features of the innermost primary wing feather (P1) and the sexually dimorphic outermost (Ta6) and monomorphic second outermost (Ta5) tail feathers of barn swallows (Hirundo rustica) from a Romanian population to investigate how sexual selection and resistance to aerodynamic forces affect structural differences among these feathers. Furthermore, we compared structural properties of Ta6 of barn swallows from six European populations. Finally, we determined the relationship between feather growth bars width (GBW) and the structural properties of tail feathers. The structure of P1 indicates strong resistance against aerodynamic forces, while the narrow rachis, low vane density and low bending stiffness of tail feathers suggest reduced resistance against airflow. The highly elongated Ta6 is characterized by structural modifications such as large rachis width and increased barbule density in relation to the less elongated Ta5, which can be explained by increased length and/or high aerodynamic forces acting at the leading tail edge. However, these changes in Ta6 structure do not allow for full compensation of elongation, as reflected by the reduced bending stiffness of Ta6. Ta6 elongation in males resulted in feathers with reduced resistance, as shown by the low barb density and reduced bending stiffness compared to females. The inconsistency in sexual dimorphism and in change in quality traits of Ta6 among six European populations shows that multiple factors may contribute to shaping population differences. In general, the difference in quality traits between tail feathers cannot be explained by the GBW of feathers. Our results show that the material and structural properties of wing and tail feathers of barn swallows change as a result of aerodynamic forces and sexual selection, although the result of these

  2. Importance of Health and Social Care Research into Gender and Sexual Minority Populations in Nepal.

    PubMed

    Regmi, Pramod R; van Teijlingen, Edwin

    2015-11-01

    Despite progressive legislative developments and increased visibility of sexual and gender minority populations in the general population, mass media often report that this population face a wide range of discrimination and inequalities. LGBT (lesbian, gay, and bisexual, and transgender) populations have not been considered as priority research populations in Nepal. Research in other geographical settings has shown an increased risk of poor mental health, violence, and suicide and higher rates of smoking, as well as alcohol and drugs use among LGBT populations. They are also risk for lifestyle-related illness such as cancer, diabetes, and heart diseases. Currently, in Nepal, there is a lack of understanding of health and well-being, social exclusion, stigma, and discrimination as experienced by these populations. Good-quality public health research can help design and implement targeted interventions to the sexual and gender minority populations of Nepal.

  3. Decreased sexual signalling reveals reduced viability in small populations of the drumming wolf spider Hygrolycosa rubrofasciata.

    PubMed Central

    Ahtiainen, Jari J.; Alatalo, Rauno V.; Mappes, Johanna; Vertainen, Laura

    2004-01-01

    One of the important goals in conservation biology is to determine reliable indicators of population viability. Sexual traits have been suggested to indicate population extinction risk, because they may be related to viability through condition dependence. Moreover, condition-dependent sexual traits may be more sensitive indicators of population viability than early life-history traits, because deleterious fitness effects of inbreeding tend to be expressed mainly at the end of the species' life history. However, empirical evidence of the significance of sexual behaviour for population viability is missing. In this study, we examined two male sexual traits and survival in 39 different-sized and isolated natural populations of the wolf spider, Hygrolycosa rubrofasciata. We also used several traits to estimate female reproductive success in 25 populations of H. rubrofasciata. According to previous studies, H. rubrofasciata males have a costly and condition-dependent acoustic signal, courtship drumming, which is the target of female choice. Males with a high drumming rate have considerably higher viability than males with a low drumming rate, and females that mate with the more actively drumming males gain genetic benefits in terms of increased offspring viability. Our results show that males in small populations had both lower survival and lower drumming rate than males in larger populations. However, we did not find any evidence for a decline in important early life-history traits (offspring number, hatching success or offspring body mass) or female body mass in small populations. Our results have two important messages for conservation biology. First, they show that sexual traits can be used as sensitive indicators of population viability. Second, the indirect benefits of female choice in terms of good genes might partially compensate for the reduction of viability in declining populations. Also, our results support the view that deleterious effects of small

  4. Decreased sexual signalling reveals reduced viability in small populations of the drumming wolf spider Hygrolycosa rubrofasciata.

    PubMed

    Ahtiainen, Jari J; Alatalo, Rauno V; Mappes, Johanna; Vertainen, Laura

    2004-09-07

    One of the important goals in conservation biology is to determine reliable indicators of population viability. Sexual traits have been suggested to indicate population extinction risk, because they may be related to viability through condition dependence. Moreover, condition-dependent sexual traits may be more sensitive indicators of population viability than early life-history traits, because deleterious fitness effects of inbreeding tend to be expressed mainly at the end of the species' life history. However, empirical evidence of the significance of sexual behaviour for population viability is missing. In this study, we examined two male sexual traits and survival in 39 different-sized and isolated natural populations of the wolf spider, Hygrolycosa rubrofasciata. We also used several traits to estimate female reproductive success in 25 populations of H. rubrofasciata. According to previous studies, H. rubrofasciata males have a costly and condition-dependent acoustic signal, courtship drumming, which is the target of female choice. Males with a high drumming rate have considerably higher viability than males with a low drumming rate, and females that mate with the more actively drumming males gain genetic benefits in terms of increased offspring viability. Our results show that males in small populations had both lower survival and lower drumming rate than males in larger populations. However, we did not find any evidence for a decline in important early life-history traits (offspring number, hatching success or offspring body mass) or female body mass in small populations. Our results have two important messages for conservation biology. First, they show that sexual traits can be used as sensitive indicators of population viability. Second, the indirect benefits of female choice in terms of good genes might partially compensate for the reduction of viability in declining populations. Also, our results support the view that deleterious effects of small

  5. Discrimination, Mental Health, and Substance Use Disorders Among Sexual Minority Populations

    PubMed Central

    Lee, Ji Hyun; Gamarel, Kristi E.; Bryant, Kendall J.; Zaller, Nickolas D.

    2016-01-01

    Abstract Purpose: Sexual minority (lesbian, gay, bisexual) populations have a higher prevalence of mental health and substance use disorders compared to their heterosexual counterparts. Such disparities have been attributed, in part, to minority stressors, including distal stressors such as discrimination. However, few studies have examined associations between discrimination, mental health, and substance use disorders by gender among sexual minority populations. Methods: We analyzed data from 577 adult men and women who self-identified as lesbian, gay, or bisexual and participated in Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). Six questions assessed discrimination due to sexual orientation. Weighted multivariable logistic regression examined associations between experiences of sexual orientation discrimination and both mental health and substance use disorders. Analyses were conducted separately for sexual minority men and women, adjusting for sociodemographic covariates. Results: Sexual minority men who ever experienced discrimination (57.4%) reported higher odds of any lifetime drug use disorder and cannabis use disorder compared to sexual minority men who never experienced discrimination. Sexual minority women who ever experienced discrimination (42.9%) reported higher odds of any lifetime mood disorder and any lifetime anxiety disorder compared to sexual minority women who never experienced discrimination. Conclusion: The findings suggest that discrimination is differentially associated with internalizing (mental health) and externalizing (substance use) disorders for sexual minority men and women. These findings indicate a need to consider how homophobia and heteronormative discrimination may contribute to distinct health outcomes for lesbian and bisexual women compared with gay and bisexual men. PMID:27383512

  6. Genetic and environmental effects on same-sex sexual behavior: a population study of twins in Sweden.

    PubMed

    Långström, Niklas; Rahman, Qazi; Carlström, Eva; Lichtenstein, Paul

    2010-02-01

    There is still uncertainty about the relative importance of genes and environments on human sexual orientation. One reason is that previous studies employed self-selected, opportunistic, or small population-based samples. We used data from a truly population-based 2005-2006 survey of all adult twins (20-47 years) in Sweden to conduct the largest twin study of same-sex sexual behavior attempted so far. We performed biometric modeling with data on any and total number of lifetime same-sex sexual partners, respectively. The analyses were conducted separately by sex. Twin resemblance was moderate for the 3,826 studied monozygotic and dizygotic same-sex twin pairs. Biometric modeling revealed that, in men, genetic effects explained .34-.39 of the variance, the shared environment .00, and the individual-specific environment .61-.66 of the variance. Corresponding estimates among women were .18-.19 for genetic factors, .16-.17 for shared environmental, and 64-.66 for unique environmental factors. Although wide confidence intervals suggest cautious interpretation, the results are consistent with moderate, primarily genetic, familial effects, and moderate to large effects of the nonshared environment (social and biological) on same-sex sexual behavior.

  7. Poppr: an R package for genetic analysis of populations with mixed (clonal/sexual) reproduction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Poppr is an R package for analysis of population genetic data. It extends the adegenet package and provides several novel tools, particularly with regard to analysis of data from admixed, clonal, and/or sexual populations. Currently, poppr can be used for dominant/codominant and haploid/diploid gene...

  8. Prevalence of sexual violence and posttraumatic stress disorder in an urban African-American population.

    PubMed

    Walsh, Kate; Koenen, Karestan C; Aiello, Allison E; Uddin, Monica; Galea, Sandro

    2014-12-01

    Sexual violence is prevalent nationally and contributes to psychopathology in the general population. Despite elevated traumatic event exposure among economically disadvantaged urban-dwelling African-Americans, there is insufficient information on lifetime sexual violence exposure and associated psychopathology in this population. In 2008-2009, 1,306 African-Americans from a Detroit household probability sample reported on lifetime rape and sexual assault and past-month and lifetime posttraumatic stress disorder (PTSD). Lifetime sexual violence prevalence was 26.3 % for women and 5.1 % for men. Relative to non-victims, sexual violence victims: reported more other traumatic events; had 4 times greater unadjusted odds of past-month and lifetime PTSD; had 1.6 times greater adjusted odds of lifetime PTSD only after controlling for other traumatic events. Sexual violence was associated with increased risk for lifetime PTSD and exposure to other traumas. Findings highlight a need to screen for sexual violence and PTSD among urban African-Americans.

  9. A Data Mining Approach to Identify Sexuality Patterns in a Brazilian University Population.

    PubMed

    Waleska Simões, Priscyla; Cesconetto, Samuel; Toniazzo de Abreu, Larissa Letieli; Côrtes de Mattos Garcia, Merisandra; Cassettari Junior, José Márcio; Comunello, Eros; Bisognin Ceretta, Luciane; Aparecida Manenti, Sandra

    2015-01-01

    This paper presents the profile and experience of sexuality generated from a data mining classification task. We used a database about sexuality and gender violence performed on a university population in southern Brazil. The data mining task identified two relationships between the variables, which enabled the distinction of subgroups that better detail the profile and experience of sexuality. The identification of the relationships between the variables define behavioral models and factors of risk that will help define the algorithms being implemented in the data mining classification task.

  10. Characteristics of Victims of Sexual Abuse by Gender and Race in a Community Corrections Population

    ERIC Educational Resources Information Center

    Clark, C. Brendan; Perkins, Adam; McCullumsmith, Cheryl B.; Islam, M. Aminul; Hanover, Erin E.; Cropsey, Karen L.

    2012-01-01

    The purpose of this study was to examine how victims of sexual abuse in a community corrections population differ as a result of their sex and race. Of the 19,422 participants, a total of 1,298 (6.7%) reported a history of sexual abuse and were compared with nonabused participants. The sample was analyzed by race-gender groups (White men, White…

  11. Population structure, parasitism, and survivorship of sexual and autodiploid parthenogenetic Campeloma limum.

    PubMed

    Johnson, S G

    2000-02-01

    Two theories for the maintenance of sexual reproduction, the Red Queen hypothesis and mutation accumulation, suggest that the dispersal rates of sexuals and asexuals may determine the elimination or persistence of asexuals. Under higher dispersal rates of asexuals, asexuals may temporarily escape virulent parasites and reduce the effects of deleterious mutations. In the present study, I examine the population structure, parasite loads, and juvenile survivorship of Campeloma limum sexuals and autodiploid parthenogens from the southeastern U.S. Atlantic coastal plain. Using mtDNA sequence variation, it is shown that parthenogenetic haplotypes with limited sequence divergence are geographically widespread throughout this region and there is no significant population differentiation over a broad geographical scale. Sexual C. limum populations show significant mtDNA differentiation among and within river drainages and there is significant isolation by distance. These patterns are consistent with a recent origin and range expansion of parthenogens. Prevalence of infection by digenetic trematodes is significantly higher in autodiploid parthenogens, and the variance of prevalence is also higher in autodiploid parthenogens. I argue that the latter pattern indicates that unparasitized parthenogens have temporarily escaped these virulent parasites, but recolonization of these populations by trematodes results in high infection levels (> 40%), possibly due to reduced variation in resistance genes. I also examined whether the survivorship of juvenile sexuals and parthenogens varied under different stress levels. Sexual juveniles had twofold higher survivorship in all environments. Compared to polyploid parthenogens, autodiploid parthenogens may be less buffered against the effects of deleterious recessive alleles. I propose that the combined effects of higher parasitism and reduced juvenile survivorship of these autodiploid parthenogens accounts for the spatial distribution of

  12. Large-scale age-dependent skewed sex ratio in a sexually dimorphic avian scavenger.

    PubMed

    Lambertucci, Sergio A; Carrete, Martina; Donázar, José Antonio; Hiraldo, Fernando

    2012-01-01

    Age-dependent skewed sex ratios have been observed in bird populations, with adult males generally outnumbering females. This trend is mainly driven by higher female mortality, sometimes associated with anthropogenic factors. Despite the large amount of work on bird sex ratios, research examining the spatial stability of adult sex ratios is extremely scarce. The Andean condor (Vultur gryphus) is the only bird of prey with strong sexual dimorphism favouring males (males are 30% heavier than females). By examining data from most of its South-American range, we show that while the juvenile sex ratio is balanced, or even female-skewed, the sex ratio becomes increasing male-skewed with age, with adult males outnumbering females by >20%, and, in some cases by four times more. This result is consistent across regions and independent of the nature of field data. Reasons for this are unknown but it can be hypothesized that the progressive disappearance of females may be associated with mortality caused by anthropogenic factors. This idea is supported by the asymmetric habitat use by the two sexes, with females scavenging in more humanized areas. Whatever the cause, male-skewed adult sex ratios imply that populations of this endangered scavenger face higher risks of extinction than previously believed.

  13. Large-Scale Age-Dependent Skewed Sex Ratio in a Sexually Dimorphic Avian Scavenger

    PubMed Central

    Lambertucci, Sergio A.; Carrete, Martina; Donázar, José Antonio; Hiraldo, Fernando

    2012-01-01

    Age-dependent skewed sex ratios have been observed in bird populations, with adult males generally outnumbering females. This trend is mainly driven by higher female mortality, sometimes associated with anthropogenic factors. Despite the large amount of work on bird sex ratios, research examining the spatial stability of adult sex ratios is extremely scarce. The Andean condor (Vultur gryphus) is the only bird of prey with strong sexual dimorphism favouring males (males are 30% heavier than females). By examining data from most of its South-American range, we show that while the juvenile sex ratio is balanced, or even female-skewed, the sex ratio becomes increasing male-skewed with age, with adult males outnumbering females by >20%, and, in some cases by four times more. This result is consistent across regions and independent of the nature of field data. Reasons for this are unknown but it can be hypothesized that the progressive disappearance of females may be associated with mortality caused by anthropogenic factors. This idea is supported by the asymmetric habitat use by the two sexes, with females scavenging in more humanized areas. Whatever the cause, male-skewed adult sex ratios imply that populations of this endangered scavenger face higher risks of extinction than previously believed. PMID:23029488

  14. Sexual Reproduction in Aspergillus flavus Sclerotia: Acquisition of Novel Alleles from Soil Populations and Uniparental Mitochondrial Inheritance

    PubMed Central

    Horn, Bruce W.; Gell, Richard M.; Singh, Rakhi; Sorensen, Ronald B.; Carbone, Ignazio

    2016-01-01

    Aspergillus flavus colonizes agricultural commodities worldwide and contaminates them with carcinogenic aflatoxins. The high genetic diversity of A. flavus populations is largely due to sexual reproduction characterized by the formation of ascospore-bearing ascocarps embedded within sclerotia. A. flavus is heterothallic and laboratory crosses between strains of the opposite mating type produce progeny showing genetic recombination. Sclerotia formed in crops are dispersed onto the soil surface at harvest and are predominantly produced by single strains of one mating type. Less commonly, sclerotia may be fertilized during co-infection of crops with sexually compatible strains. In this study, laboratory and field experiments were performed to examine sexual reproduction in single-strain and fertilized sclerotia following exposure of sclerotia to natural fungal populations in soil. Female and male roles and mitochondrial inheritance in A. flavus were also examined through reciprocal crosses between sclerotia and conidia. Single-strain sclerotia produced ascospores on soil and progeny showed biparental inheritance that included novel alleles originating from fertilization by native soil strains. Sclerotia fertilized in the laboratory and applied to soil before ascocarp formation also produced ascospores with evidence of recombination in progeny, but only known parental alleles were detected. In reciprocal crosses, sclerotia and conidia from both strains functioned as female and male, respectively, indicating A. flavus is hermaphroditic, although the degree of fertility depended upon the parental sources of sclerotia and conidia. All progeny showed maternal inheritance of mitochondria from the sclerotia. Compared to A. flavus populations in crops, soil populations would provide a higher likelihood of exposure of sclerotia to sexually compatible strains and a more diverse source of genetic material for outcrossing. PMID:26731416

  15. Sexual Reproduction in Aspergillus flavus Sclerotia: Acquisition of Novel Alleles from Soil Populations and Uniparental Mitochondrial Inheritance.

    PubMed

    Horn, Bruce W; Gell, Richard M; Singh, Rakhi; Sorensen, Ronald B; Carbone, Ignazio

    2016-01-01

    Aspergillus flavus colonizes agricultural commodities worldwide and contaminates them with carcinogenic aflatoxins. The high genetic diversity of A. flavus populations is largely due to sexual reproduction characterized by the formation of ascospore-bearing ascocarps embedded within sclerotia. A. flavus is heterothallic and laboratory crosses between strains of the opposite mating type produce progeny showing genetic recombination. Sclerotia formed in crops are dispersed onto the soil surface at harvest and are predominantly produced by single strains of one mating type. Less commonly, sclerotia may be fertilized during co-infection of crops with sexually compatible strains. In this study, laboratory and field experiments were performed to examine sexual reproduction in single-strain and fertilized sclerotia following exposure of sclerotia to natural fungal populations in soil. Female and male roles and mitochondrial inheritance in A. flavus were also examined through reciprocal crosses between sclerotia and conidia. Single-strain sclerotia produced ascospores on soil and progeny showed biparental inheritance that included novel alleles originating from fertilization by native soil strains. Sclerotia fertilized in the laboratory and applied to soil before ascocarp formation also produced ascospores with evidence of recombination in progeny, but only known parental alleles were detected. In reciprocal crosses, sclerotia and conidia from both strains functioned as female and male, respectively, indicating A. flavus is hermaphroditic, although the degree of fertility depended upon the parental sources of sclerotia and conidia. All progeny showed maternal inheritance of mitochondria from the sclerotia. Compared to A. flavus populations in crops, soil populations would provide a higher likelihood of exposure of sclerotia to sexually compatible strains and a more diverse source of genetic material for outcrossing.

  16. High rates of sexual behavior in the general population: correlates and predictors.

    PubMed

    Långström, Niklas; Hanson, R Karl

    2006-02-01

    We studied 2450, 18-60-year-old men and women from a 1996 national survey of sexuality and health in Sweden to identify risk factors and correlates of elevated rates of sexual behavior (hypersexuality) in a representative, non-clinical population. Interviews and questionnaires measured various sexual behaviors, developmental risk factors, behavioral problems, and health indicators. The results suggested that correlates of high rates of intercourse were mostly positive, whereas the correlates of high rates of masturbation and impersonal sex were typically undesirable. For both men and women, high rates of impersonal sex were related to separation from parents during childhood, relationship instability, sexually transmitted disease, tobacco smoking, substance abuse, and dissatisfaction with life in general. The association between hypersexuality and paraphilic sexual interests (exhibitionism, voyeurism, masochism/sadism) was particularly and equally strong for both genders (odds ratios of 4.6-25.6). The results held, with a few exceptions, when controlling for age, being in a stable relationship, living in a major city, and same-sex sexual orientation. We conclude that elevated rates of impersonal sex are associated with a range of negative health indicators in the general population.

  17. Within-population covariation between sexual reproduction and susceptibility to local parasites.

    PubMed

    Gibson, Amanda K; Xu, Julie Y; Lively, Curtis M

    2016-09-01

    Evolutionary biology has yet to reconcile the ubiquity of sex with its costs relative to asexual reproduction. Here, we test the hypothesis that coevolving parasites maintain sex in their hosts. Specifically, we examined the distributions of sexual reproduction and susceptibility to local parasites within a single population of freshwater snails (Potamopyrgus antipodarum). Susceptibility to local trematode parasites (Microphallus sp.) is a relative measure of the strength of coevolutionary selection in this system. Thus, if coevolving parasites maintain sex, sexual snails should be common where susceptibility is high. We tested this prediction in a mixed population of sexual and asexual snails by measuring the susceptibility of snails from multiple sites in a lake. Consistent with the prediction, the frequency of sexual snails was tightly and positively correlated with susceptibility to local parasites. Strikingly, in just two years, asexual females increased in frequency at sites where susceptibility declined. We also found that the frequency of sexual females covaries more strongly with susceptibility than with the prevalence of Microphallus infection in the field. In linking susceptibility to the frequency of sexual hosts, our results directly implicate spatial variation in coevolutionary selection in driving the geographic mosaic of sex.

  18. Diet selection and seasonal dietary switch of a large sexually dimorphic herbivore

    NASA Astrophysics Data System (ADS)

    Shannon, Graeme; Mackey, Robin L.; Slotow, Rob

    2013-01-01

    Although diet selection and the physiological adaptations of grazers and browsers have been widely studied, much less is known about mixed-feeders that target both grass and woody species. The ability to switch diet allows the individual to respond to spatial and temporal changes in forage abundance and quality, providing a key mechanism for large herbivores to exploit heterogeneous environments. We compare diet selection and timing of the seasonal dietary switch for a large-bodied, sexually dimorphic mixed-feeder, the African elephant. The study was carried out on a small population of elephants (n = 48) in the Pongola Game Reserve (PGR), South Africa. Sex-specific dietary composition evaluated from feeding behaviour correlated with composition in dung samples from individuals of known sex. Grass was strongly preferred during the wet season and browse in the winter dry season. However, adult male elephants switched from browse to grass earlier, and consumed a greater overall proportion of grass in their diet, compared with adult females and their associated family groups. Male elephants also spent more time in grassland habitats, and expanded their ranges to a greater extent than females following the end of the dry season. Our results suggest that smaller adult body size, high nutritional demands of offspring, and the constraints of sociality have contributed to female elephants in PGR resolving their diet selection strategies to target higher quality foraging opportunities, whilst males appear to be adopting a rate maximizing approach. The behavioural differences between the sexes are pronounced, which has implications for elephant management approaches that are typically focussed at the population level.

  19. Age of Sexual Consent Law in Canada: Population-Based Evidence for Law and Policy

    PubMed Central

    Miller, Bonnie B.; Cox, David N.; Saewyc, Elizabeth M.

    2015-01-01

    This study evaluated the implications of the 2008 increase in age for sexual consent in Canada using a population health survey of Canadian adolescents. Government rationales for the increase asserted younger adolescents were more likely to experience sexual exploitation and engage in risky sexual behaviour than adolescents 16 and older. Using data from sexually experienced adolescents in the 2008 British Columbia Adolescent Health Survey (BC AHS, N=6,262; age range 12 – 19; 52% female), analyses documented the scope of first intercourse partners who were not within the ‘close in age’ exemptions, then compared sexual behaviours of younger teens (14 and 15 years) with older teens (16 and 17) navigating their first year of sexual activity. Comparisons included: forced sex, sex under the influence of alcohol or drugs, multiple partners, condom use, effective contraception use, self-reported sexually transmitted infections, and pregnancy involvement. Results showed very few 14- and 15-year-olds had first intercourse partners who were not within the ‘close in age’ exemptions based on age (boys: <2%, girls: 3–5%). In contrast, among 12- and 13-year-olds (a group unaffected by the law’s change) between 25% and 50% had first intercourse partners who were not within the ‘close in age’ exemptions, and almost 40% of teens who first had sex before age 12 reported a first partner age 20 years or more. In their first year of intercourse, 14- and 15-year-olds were slightly more likely to report forced sex and 3 or more partners than older teens, but otherwise made similarly healthy decisions. This study demonstrates the feasibility of evaluating policy using population health data and shows that better strategies are needed to protect children 13 and under from sexual abuse. PMID:27087775

  20. Populations with elevated mutation load do not benefit from the operation of sexual selection.

    PubMed

    Hollis, B; Houle, D

    2011-09-01

    Theory predicts that if most mutations are deleterious to both overall fitness and condition-dependent traits affecting mating success, sexual selection will purge mutation load and increase nonsexual fitness. We explored this possibility with populations of mutagenized Drosophila melanogaster exhibiting elevated levels of deleterious variation and evolving in the presence or absence of male-male competition and female choice. After 60 generations of experimental evolution, monogamous populations exhibited higher total reproductive output than polygamous populations. Parental environment also affected fitness measures - flies that evolved in the presence of sexual conflict showed reduced nonsexual fitness when their parents experienced a polygamous environment, indicating trans-generational effects of male harassment and highlighting the importance of a common garden design. This cost of parental promiscuity was nearly absent in monogamous lines, providing evidence for the evolution of reduced sexual antagonism. There was no overall difference in egg-to-adult viability between selection regimes. If mutation load was reduced by the action of sexual selection in this experiment, the resultant gain in fitness was not sufficient to overcome the costs of sexual antagonism.

  1. Population, sexual and reproductive health, rights and sustainable development: forging a common agenda.

    PubMed

    Newman, Karen; Fisher, Sarah; Mayhew, Susannah; Stephenson, Judith

    2014-05-01

    This article suggests that sexual and reproductive health and rights activists seeking to influence the post-2015 international development paradigm must work with sustainable development advocates concerned with a range of issues, including climate change, environmental issues, and food and water security, and that a way of building bridges with these communities is to demonstrate how sexual and reproductive health and rights are relevant for these issues. An understanding of population dynamics, including urbanization and migration, as well as population growth, can help to clarify these links. This article therefore suggests that whether or not sexual and reproductive health and rights activists can overcome resistance to discussing "population", become more knowledgeable about other sustainable development issues, and work with others in those fields to advance the global sustainable development agenda are crucial questions for the coming months. The article also contends that it is possible to care about population dynamics (including ageing and problems faced by countries with a high proportion of young people) and care about human rights at the same time. It expresses concern that, if sexual and reproductive health and rights advocates do not participate in the population dynamics discourse, the field will be left free for those for whom respecting and protecting rights may be less of a priority.

  2. Factors associated with treatment compliance in a population of juvenile sexual offenders.

    PubMed

    Hunter, J A; Figueredo, A J

    1999-01-01

    Structural equation modeling was utilized to assess predictors of outcomes in a sample of 204 juvenile male sexual offenders participating in community-based treatment programming. Lower levels of client denial at intake predicted successful program compliance. Higher levels of denial were found in nonadjudicated youths. Although program attrition was high (50% in the first year), relatively few youths were expelled for sexual (4.9%) or nonsexual delinquency (6.6%) over a 12- to 24-month period. Program failure during years 1 and 2 was attributable largely to expulsion for failure to comply with attendance requirements and/or therapeutic directives. Youths failing to comply were found to have higher overall levels of measured sexual maladjustment and may be at greater long-term risk for sexual recidivism. Implications of the findings for clinical risk assessment, and directions for future research, are discussed.

  3. Parental Opinion Concerning School Sexuality Education in a Culturally Diverse Population in the USA

    ERIC Educational Resources Information Center

    Heller, Janet R.; Johnson, Helen L.

    2013-01-01

    This study aimed to expand upon previous research related to parental opinion concerning school sexuality education by sampling a culturally diverse, low-income population that has been traditionally under-represented in the literature. A total of 191 parents attending an urban community college completed a written questionnaire about what topics…

  4. Sexual violence and neonatal outcomes: a Norwegian population-based cohort study

    PubMed Central

    Henriksen, Lena; Schei, Berit; Vangen, Siri; Lukasse, Mirjam

    2014-01-01

    Objective The objective of this study was to explore the association between sexual violence and neonatal outcomes. Design National cohort study. Setting Women were recruited to the Norwegian Mother and Child Cohort Study (MoBa) while attending routine ultrasound examinations from 1999 to 2008. Population A total of 76 870 pregnant women. Methods Sexual violence and maternal characteristics were self-reported in postal questionnaires during pregnancy. Neonatal outcomes were retrieved from the Medical Birth Registry of Norway (MBRN). Risk estimations were performed with linear and logistic regression analysis. Outcome measures: gestational age at birth, birth weight, preterm birth (PTB), low birth weight (LBW) and small for gestational age (SGA). Results Of 76 870 women, 18.4% reported a history of sexual violence. A total of 4.7% delivered prematurely, 2.7% had children with a birth weight <2500 g and 8.1% children were small for their gestational age. Women reporting moderate or severe sexual violence (rape) had a significantly reduced gestational length (2 days) when the birth was provider-initiated in an analysis adjusted for age, parity, education, smoking, body mass index and mental distress. Those exposed to severe sexual violence had a significantly reduced gestational length of 0.51 days with a spontaneous start of birth. Crude estimates showed that severe sexual violence was associated with PTB, LBW and SGA. When controlling for the aforementioned sociodemographic and behavioural factors, the association was no longer significant. Conclusions Sexual violence was not associated with adverse neonatal outcomes. Moderate and severe violence had a small but significant effect on gestational age; however, the clinical influence of this finding is most likely limited. Women exposed to sexual violence in this study reported more of the sociodemographic and behavioural factors associated with PTB, LBW and SGA compared with non-abused women. PMID:25763796

  5. Mate choice theory and the mode of selection in sexual populations.

    PubMed

    Carson, Hampton L

    2003-05-27

    Indirect new data imply that mate and/or gamete choice are major selective forces driving genetic change in sexual populations. The system dictates nonrandom mating, an evolutionary process requiring both revised genetic theory and new data on heritability of characters underlying Darwinian fitness. Successfully reproducing individuals represent rare selections from among vigorous, competing survivors of preadult natural selection. Nonrandom mating has correlated demographic effects: reduced effective population size, inbreeding, low gene flow, and emphasis on deme structure. Characters involved in choice behavior at reproduction appear based on quantitative trait loci. This variability serves selection for fitness within the population, having only an incidental relationship to the origin of genetically based reproductive isolation between populations. The claim that extensive hybridization experiments with Drosophila indicate that selection favors a gradual progression of "isolating mechanisms" is flawed, because intra-group random mating is assumed. Over deep time, local sexual populations are strong, independent genetic systems that use rich fields of variable polygenic components of fitness. The sexual reproduction system thus particularizes, in small subspecific populations, the genetic basis of the grand adaptive sweep of selective evolutionary change, much as Darwin proposed.

  6. Serotonin reuptake inhibitor-induced sexual dysfunction and its treatment: a large-scale retrospective study of 596 psychiatric outpatients.

    PubMed

    Keller Ashton, A; Hamer, R; Rosen, R C

    1997-01-01

    In the present study, a large-scale retrospective case review was undertaken to assess the incidence and type of sexual dysfunctions associated with serotonin reuptake inhibitor (SRI) therapy, in addition to the effects of three pharmacological antidotes (yohimbine, amantadine, cyproheptadine) on SRI-induced sexual dysfunctions. A retrospective chart review was conducted on 596 patients treated with SRIs in an outpatient psychiatric practice between July 1991 and September 1994. Patients who reported new-onset sexual dysfunction during this time were categorized as having SRI-induced sexual dysfunctions. Sexual difficulties were characterized by type and duration, and the background characteristics and psychiatric diagnoses of all patients were recorded. Psychiatric outcome and sexual functioning at follow-up were independently assessed by a single psychiatrist by means of a 4-point rating scale. Sexual dysfunction symptoms were clearly associated with SRI administration in 97 (16.3%) cases. The most common problems reported were orgasmic delay or anorgasmia and hypoactive sexual desire. Sexual difficulties were more frequent among men (23.4%) and married patients of both sexes (22.3%), whereas psychiatric diagnosis and type of SRI were unrelated to the occurrence of sexual problems. Of the patients with sexual dysfunction, 45 (46.4%) opted for a trial of antidote therapy with yohimbine, amantadine, or cyproheptadine. All three antidotes were found to be safe and relatively effective, although yohimbine was significantly more effective than amantadine or cyproheptadine in reversing SRI-induced sexual dysfunction.

  7. Religiosity and Risky Sexual Behaviors among an African American Church-based Population

    PubMed Central

    Hawes, Starlyn M.; Berkley-Patton, Jannette Y.

    2014-01-01

    African Americans are disproportionately burdened by STDs and HIV in the US. This study examined the relationships between demographics, religiosity, and sexual risk behaviors among 255 adult African American church-based participants. Although participants were highly religious, they reported an average of seven lifetime sex partners and most inconsistently used condoms. Several demographic variables and religiosity significantly predicted lifetime HIV-related risk factors. Taken together, findings indicated that this population is at risk for HIV. Future research should continue to identify correlates of risky sexual behavior among African American parishioners to facilitate the development of HIV risk reduction interventions in their church settings. PMID:23054481

  8. Effects of individual and population parameters on reproductive success in three sexually deceptive orchid species.

    PubMed

    Vandewoestijne, S; Róis, A S; Caperta, A; Baguette, M; Tyteca, D

    2009-05-01

    Reproductive success (RS) in orchids in general, and in non-rewarding species specifically, is extremely low. RS is pollinator and pollination limited in food deceptive orchids, but this has rarely been studied in sexually deceptive orchid species. Here, we tested the effects of several individual (plant height, inflorescence size, nearest neighbour distance and flower position) and population (patch geometry, population density and size) parameters on RS in three sexually deceptive Ophrys (Orchidaceae) species. Inter-specific differences were observed in RS of flowers situated in the upper versus the lower part of the inflorescence, likely due to species-specific pollinator behaviour. For all three species examined, RS increased with increasing plant height, inflorescence size and nearest neighbour distance. RS generally increased with decreasing population density and increasing patch elongation. Given these results, we postulate that pollinator availability, rather than pollinator learning, is the most limiting factor in successful reproduction for sexually deceptive orchids. Our results also suggest that olfactory 'display' (i.e. versus optical display), in terms of inflorescence size (and co-varying plant height), plays a key role in individual RS of sexually deceptive orchids. In this regard, several hypotheses are suggested and discussed.

  9. Evolution of Population with Sexual and Asexual Reproduction in Changing Environment

    NASA Astrophysics Data System (ADS)

    He, Mingfeng; Yu, Changliang; Ruan, Hongbo; Yao, Lei

    Using a lattice model based on Monte Carlo simulations, we study the role of the reproduction pattern on the fate of an evolving population. Each individual is under the selection pressure from the environment and random mutations. The habitat ("climate") is changing periodically. Evolutions of populations following two reproduction patterns are compared, asexual and sexual. We show, via Monte Carlo simulations, that sexual reproduction by keeping more diversified populations gives them better chances to adapt themselves to the changing environment. However, in order to obtain a greater chance to mate, the birth rate should be high. In the case of low birth rate and high mutation probability there is a preference for the asexual reproduction.

  10. Sexual isolation between sympatric and allopatric populations of Drosophila pseudoobscura and D. persimilis.

    PubMed

    Anderson, Wyatt W; Kim, Yong-Kyu

    2005-05-01

    According to reinforcement theory, sexual isolation between species in sympatry is strengthened by natural selection against maladaptive hybrids. Drosophila pseudoobscura and D. persimilis from four locations where these species are sympatric, and from three locations where only D. pseudoobscura has been found, were utilized in studies of sexual isolation. Multiple-choice observation chambers were used to record matings between sympatric and allopatric strains of the two species. There was a wide variation in sexual isolation between the two species in the four localities we studied. The average isolation index for sympatric strains of the species was not significantly different from the average index for allopatric strains. There were no meaningful differences between the isolation indices in sympatric and allopatric strains of the species. The failure to find a relationship is likely the result of gene flow among populations within the two species.

  11. Migration, sexual behaviour, and HIV risk: a general population cohort in rural South Africa

    PubMed Central

    McGrath, Nuala; Eaton, Jeffrey W; Newell, Marie-Louise; Hosegood, Victoria

    2015-01-01

    Summary Background Increased sexual risk behaviour and HIV prevalence have been reported in migrants compared with non-migrants in sub-Saharan Africa. We investigated the association of residential and migration patterns with sexual HIV risk behaviours and HIV prevalence in an open, general population cohort in rural KwaZulu-Natal, South Africa. Methods In a mainly rural demographic surveillance area in northern KwaZulu-Natal, South Africa, we collected longitudinal demographic, migration, sexual behaviour, and HIV status data through household surveillance twice per year and individual surveillance once per year. All resident household members and a sample of non-resident household members (stratified by sex and migration patterns) were eligible for participation. Participants reported sexual risk behaviours, including data for multiple, concurrent, and casual sexual partners and condom use, and gave a dried blood spot sample via fingerprick for HIV testing. We investigated population-level differences in sexual HIV risk behaviours and HIV prevalence with respect to migration indicators using logistic regression models. Findings Between Jan 1, 2005, and Dec 31, 2011, the total eligible population at each surveillance round ranged between 21 129 and 22 726 women (aged 17–49 years) and between 20 399 and 22 100 men (aged 17–54 years). The number of eligible residents in any round ranged from 24 395 to 26 664 and the number of eligible non-residents ranged from 17 002 to 18 891 between rounds. The stratified sample of non-residents included between 2350 and 3366 individuals each year. Sexual risk behaviours were significantly more common in non-residents than in residents for both men and women. Estimated differences in sexual risk behaviours, but not HIV prevalence, varied between the migration indicators: recent migration, mobility, and migration type. HIV prevalence was significantly increased in current residents with a recent history of

  12. Qualitative finger and palmar dermatoglyphics: sexual dimorphism in the Chuvashian population of Russia.

    PubMed

    Karmakar, B; Yakovenko, K; Kobyliansky, E

    2007-12-01

    Qualitative finger and palmar dermatoglyphics of 547 individuals (293 males, 254 females) belonging to the Chuvashian population of Russia were studied to determine sexual dimorphism. The pattern types are not uniformly distributed on 10 fingers. Sex difference is homogeneous in all fingers whereas palmar patterns reflect the better sex variations for three palmar configurational areas (II, III, and IV). This is perhaps due to embryological development, having a relatively longer growth period compared with fingers (Cummins 1929). The present results of the Chuvashian population are not similar to the results of the five Indian populations of our previous study (Karmakar et al. 2002), perhaps due to a major ethnic difference.

  13. Sexual violence, mood disorders and suicide risk: a population-based study.

    PubMed

    Mondin, Thaíse Campos; Cardoso, Taiane de Azevedo; Jansen, Karen; Konradt, Caroline Elizabeth; Zaltron, Rosana Ferrazza; Behenck, Monalisa de Oliveira; de Mattos, Luciano Dias; da Silva, Ricardo Azevedo

    2016-03-01

    This article seeks to analyze the association between sexual violence, manic and depressive episodes, and suicide risk among young adults. This is a cross-sectional population-based study carried out with young people between 18 and 24 years of age in a town in southern Brazil. The sample was selected through clusters. The prevalence of sexual violence, manic, depressive and mixed episodes and suicide risk were evaluated, as well as the association between them. The chi-square test and Poisson regression were used for statistical analysis. The study sample comprised 1,560 subjects. Among these, 3.1% had suffered sexual violence at some point in their life. The prevalence of depressive, mixed episodes, and (hypo)manic episodes were 10%, 2.4% and 2.3%, respectively. Suicide risk had a prevalence of 8.6% in the total sample. Young people who have suffered sexual violence are more likely to be subject to mood changes or suicide risk than those who have not (p < 0.05), except for the occurrence of (hypo)manic episodes. These results revealed a strong association between sexual violence and depressive and mixed episodes and suicide risk.

  14. Childhood gender-typed behavior and adolescent sexual orientation: A longitudinal population-based study.

    PubMed

    Li, Gu; Kung, Karson T F; Hines, Melissa

    2017-04-01

    Lesbian and gay individuals have been reported to show more interest in other-sex, and/or less interest in same-sex, toys, playmates, and activities in childhood than heterosexual counterparts. Yet, most of the relevant evidence comes from retrospective studies or from prospective studies of clinically referred, extremely gender nonconforming children. In addition, findings are mixed regarding the relation between childhood gender-typed behavior and the later sexual orientation spectrum from exclusively heterosexual to exclusively lesbian/gay. The current study drew a sample (2,428 girls and 2,169 boys) from a population-based longitudinal study, and found that the levels of gender-typed behavior at ages 3.5 and 4.75 years, although less so at age 2.5 years, significantly and consistently predicted adolescents' sexual orientation at age 15 years, both when sexual orientation was conceptualized as 2 groups or as a spectrum. In addition, within-individual change in gender-typed behavior during the preschool years significantly related to adolescent sexual orientation, especially in boys. These results suggest that the factors contributing to the link between childhood gender-typed behavior and sexual orientation emerge during early development. Some of those factors are likely to be nonsocial, because nonheterosexual individuals appear to diverge from gender norms regardless of social encouragement to conform to gender roles. (PsycINFO Database Record

  15. Has the inbreeding load for a condition-dependent sexual signalling trait been purged in insular lizard populations?

    PubMed

    Runemark, Anna; Hansson, Bengt; Ljungqvist, Marcus; Brydegaard, Mikkel; Svensson, Erik I

    2013-03-01

    Sexually selected traits are often condition-dependent and are expected to be affected by genome-wide distributed deleterious mutations and inbreeding. However, sexual selection is a powerful selective force that can counteract inbreeding through purging of deleterious mutations. Inbreeding and purging of the inbreeding load for sexually selected traits has rarely been studied across natural populations with different degrees of inbreeding. Here we investigate inbreeding effects (measured as marker-based heterozygosity) on condition-dependent sexually selected signalling trait and other morphological traits across islet- and mainland populations (n = 15) of an endemic lizard species (Podarcis gaigeae). Our data suggest inbreeding depression on a condition-dependent sexually selected signalling character among mainland subpopulations with low or intermediate levels of inbreeding, but no sign of inbreeding depression among small and isolated islet populations despite their higher overall inbreeding levels. In contrast, there was no such pattern among ten other morphological traits which are primarily naturally selected and presumably not involved in sexual signalling. These results are in line with purging of recessive deleterious alleles, or purging in combination with stochastic fixation of alleles by genetic drift, for a sexual signalling character in the islet environment, which is characterized by low population sizes and strong sexual selection. Higher clutch sizes in islet populations also raise interesting questions regarding the possibility of antagonistic pleiotropy. Purging and other non-exclusive explanations of our results are discussed.

  16. Multivariate sexual selection on male tegmina in wild populations of sagebrush crickets, Cyphoderris strepitans (Orthoptera: Haglidae).

    PubMed

    Ower, G D; Hunt, J; Sakaluk, S K

    2017-02-01

    Although the strength and form of sexual selection on song in male crickets have been studied extensively, few studies have examined selection on the morphological structures that underlie variation in males' song, particularly in wild populations. Geometric morphometric techniques were used to measure sexual selection on the shape, size and symmetry of both top and bottom tegmina in wild populations of sagebrush crickets, a species in which nuptial feeding by females imposes an unambiguous phenotypic marker on males. The size of the tegmina negatively covaried with song dominant frequency and positively covaried with song pulse duration. Sexual selection was more intense on the bottom tegmen, conceivably because it interacts more freely with the subtegminal airspace, which may play a role in song amplification. An expanded coastal/subcostal region was one of the phenotypes strongly favoured by disruptive selection on the bottom tegmen, an adaptation that may form a more effective seal with the thorax to prevent noise cancellation. Directional selection also favoured increased symmetry in tegminal shape. Assuming more symmetrical males are better able to buffer against developmental noise, the song produced by these males may make them more attractive to females. Despite the strong stabilizing selection documented previously on the dominant frequency of the song, stabilizing selection on the resonator that regulates dominant frequency was surprisingly absent. Nonetheless, wing morphology had an important influence on song structure and appears to be subject to significant linear and nonlinear sexual selection through female mate choice.

  17. Rapid differentiation of sexual signals in invasive toads: call variation among populations

    PubMed Central

    Yasumiba, Kiyomi; Duffy, Richard L.; Parsons, Scott A.; Alford, Ross A.; Schwarzkopf, Lin

    2016-01-01

    Advertisement calls tend to differ among populations, based on morphological and environmental factors, or simply geographic distance, in many taxa. Invasive cane toads (Rhinella marina) were introduced to Australia in 1935 and their distribution has expanded at increasing rates over time. Rapid evolution occurred in morphological and behavioural characters that accelerate dispersal, but the effects of rapid expansion on sexual signals have not been examined. We collected advertisement calls from four populations of different ages since invasion, and analysed the geographic differentiation of seven call parameters. Our comparisons indicate that the calls of R. marina differ among Australian populations. The signal variation was not simply clinal with respect to population age, climate, or morphological differentiation. We suggest that selection on signalling among populations has been idiosyncratic and may reflect local female preferences or adaptation to environmental factors that are not clinal such as energy availability. PMID:27328666

  18. Risk factors influencing non-use of condoms at sexual relations in populations under heightened risk.

    PubMed

    Medić, Alan; Dzelalija, Boris; Koźul, Karlo; Novosel, Iva Pem; Dijanić, Tomislav

    2014-09-01

    To determine risk factors for non-use of condoms when engaging in sexual intercourse among high-risk population groups for acquiring HIV/STIs. We collected the data obtained by interviews in the period from 2005 to 2011 in the Voluntary Counseling and Testing Center for HIV/AIDS at the Institute of Public Health of Zadar County. Four hundred ninety four respondents were divided into risk and control groups. The majority of the respondents in our population does not consistently use condoms, in the risk group as much as 89.9%, and in the control group 65.7% of them (p< 0.001). Persons consuming alcohol when having sexual relations use condoms about 5x less often compared to those not consuming alcohol at all (OR=5.00; CI=1.69-14.29). There are significant differences among women and men in the risk group regarding reasons for non-use of condoms. The main reason with women is "I trust mypartners" 33.7% while men "do not like having sex with condoms, 53.6% of them (p < 0.001). The main risk factors for non-use of condoms are alcohol consumption at sexual relations, non-use of condoms in a casual relationship. Having in mind the non-use of condoms among populations of high-risk groups of acquiring HIV there are significant differences among genders.

  19. The Mental Health of Sexual Minority Adults In and Out of the Closet: A Population-Based Study

    PubMed Central

    Pachankis, John E.; Cochran, Susan D.; Mays, Vickie M.

    2015-01-01

    Objectives Previous studies find that sexual orientation concealment affords escape from stigma and discrimination but also creates a psychological toll. While disclosure alleviates the mental burden of concealment, it invites the stress of navigating a new public identity. Population-based samples that include both “in” and “out” sexual minorities provide an ideal opportunity to resolve limitations and inconsistencies of previous non-probability investigations into the mental health correlates of concealment and disclosure. Method Sexual minority participants in the California Quality of Life Survey (n=2,083) indicated whether and when they had first disclosed their sexual orientation to others. Prevalence of one-year major depressive disorder and generalized anxiety disorder was derived from the Composite International Diagnostic Interview Short Form. Results Closeted men (n=84) were less likely to be depressed than out men (n=1,047; OR=0.41 95% CI: 0.17-0.996). Men who were recently out (n=201) experienced higher odds of major depressive disorder (OR=6.21 95% CI: 1.53-24.47) and generalized anxiety disorder (OR=5.51 95% CI: 1.51-20.13) as compared to closeted men. Men who were distantly out (n = 846) also experienced higher odds of major depressive disorder than men who were closeted (OR=2.91; 95% CI: 1.10-7.69). Recently out women (n=243) experienced lower odds of depression than closeted women (n=63) (OR=0.21; 95% CI: 0.05-0.96). Conclusion Whether being in or out of the closet is associated with depression and anxiety largely depends on gender. Clinical and policy implications are discussed in terms of the unique stressors facing men and women both in and out of the closet. PMID:26280492

  20. Sexual assault while too intoxicated to resist: a general population study of Norwegian teenage girls

    PubMed Central

    2014-01-01

    Background Underage drinking is widespread, but studies on alcohol-related sexual victimization among teenage girls are almost non-existent. Research on individual correlates and risk factors of sexual victimization more generally is also meager. This study focuses on sexual assault while incapacitated due to drunkenness among 15–18 year-old girls and examines how age, drinking behavior, impulsivity and involvement in norm-violating activities are associated with such victimization experiences. Methods Data stemmed from a school survey (response rate: 85%) in 16 Norwegian municipalities. Almost all analyses were restricted to girls who had been intoxicated in the past year (n = 2701). In addition to bivariate associations, adjusted odds ratios and relative risks of incapacitated sexual assault (ISA) were estimated. Further, population-attributable fractions were calculated to explore how the prevalence of ISA victimization was likely to be affected if effective preventive measures were targeted solely at high-risk groups. Results The majority of the girls (71%) had been intoxicated in the past year, of which 7% had experienced ISA victimization in the same period. The proportion of victims decreased by age within the group that had been intoxicated, reflecting that the youngest girls were more likely to get severely drunk. Impulsivity and involvement in norm-violating behaviors were identified as potential risk factors, but the population-attributable fractions indicated that the groups with the highest risk of ISA victimization accounted for only a minority of all the cases of such victimization. Conclusion Sexual assault against teenage girls who are too drunk to resist seems to be prevalent in Norway – notably among the youngest girls who engage in heavy episodic drinking. This study also suggests that one should reconsider the notion that no individual attributes are related to females’ sexual assault victimization. It also indicates that a high risk

  1. Evolutionary divergence in sexual signals: Insights from within and among barn swallow populations

    NASA Astrophysics Data System (ADS)

    Wilkins, Matthew Reed

    A wealth of studies across diverse animal groups indicate the importance of sexual selection in shaping phenotypes within and across breeding populations. In recent decades, much research has focused on how divergent sexual selection pressures among populations may lead to speciation. For my first dissertation chapter, I performed a literature review on the causes and consequences of evolutionary divergence in acoustic signals and developed the acoustic window conceptual framework for understanding the contributions of selection, genetic drift, and evolutionary constraint to signal divergence. Further, I found that sexual selection explains acoustic differences between recently diverged populations of the best-studied taxa. However, the relative contributions of ecological selection, sexual selection, and drift to acoustic divergence have not typically been considered within the same study systems. The remainder of my dissertation used the Northern Hemisphere-distributed barn swallow ( Hirundo rustica) species complex as a model system to study sender-receiver dynamics, intra- and intersexual selection pressures, and visual and acoustic signal interactions at the local scale, and signal divergence across populations at the global scale. From song recordings taken across 19 sampling sites, spanning five of six described subspecies, I demonstrated considerable conservation in song structure. However, temporal traits were highly divergent across subspecies, and in particular, the speed of the terminal trill of songs. In a detailed study of the multimodal communication system of the barn swallow (including visual and acoustic traits), I demonstrated that males and females use different types of signals to mediate competition and mate choice. One of the only exceptions to this rule was trill rate, which was also implicated in song divergence across populations. In order to test the function of trill rate in communication, I performed a two-year playback study within the

  2. Sexual dimorphism of the mandible in a contemporary Chinese Han population.

    PubMed

    Dong, Hongmei; Deng, Mohong; Wang, WenPeng; Zhang, Ji; Mu, Jiao; Zhu, Guanghui

    2015-10-01

    A present limitation of forensic anthropology practice in China is the lack of population-specific criteria on contemporary human skeletons. In this study, a sample of 203 maxillofacial Cone beam computed tomography (CBCT) images, including 96 male and 107 female cases (20-65 years old), was analyzed to explore mandible sexual dimorphism in a population of contemporary adult Han Chinese to investigate the potential use of the mandible as sex indicator. A three-dimensional image from mandible CBCT scans was reconstructed using the SimPlant Pro 11.40 software. Nine linear and two angular parameters were measured. Discriminant function analysis (DFA) and logistic regression analysis (LRA) were used to develop the mathematics models for sex determination. All of the linear measurements studied and one angular measurement were found to be sexually dimorphic, with the maximum mandibular length and bi-condylar breadth being the most dimorphic by univariate DFA and LRA respectively. The cross-validated sex allocation accuracies on multivariate were ranged from 84.2% (direct DFA), 83.5% (direct LRA), 83.3% (stepwise DFA) to 80.5% (stepwise LRA). In general, multivariate DFA yielded a higher accuracy and LRA obtained a lower sex bias, and therefore both DFA and LRA had their own advantages for sex determination by the mandible in this sample. These results suggest that the mandible expresses sexual dimorphism in the contemporary adult Han Chinese population, indicating an excellent sexual discriminatory ability. Cone beam computed tomography scanning can be used as alternative source for contemporary osteometric techniques.

  3. Analyses of odontometric sexual dimorphism and sex assessment accuracy on a large sample.

    PubMed

    Angadi, Punnya V; Hemani, S; Prabhu, Sudeendra; Acharya, Ashith B

    2013-08-01

    Correct sex assessment of skeletonized human remains allows investigators to undertake a more focused search of missing persons' files to establish identity. Univariate and multivariate odontometric sex assessment has been explored in recent years on small sample sizes and have not used a test sample. Consequently, inconsistent results have been produced in terms of accuracy of sex allocation. This paper has derived data from a large sample of males and females, and applied logistic regression formulae on a test sample. Using a digital caliper, buccolingual and mesiodistal dimensions of all permanent teeth (except third molars) were measured on 600 dental casts (306 females, 294 males) of young adults (18-32 years), and the data subjected to univariate (independent samples' t-test) and multivariate statistics (stepwise logistic regression analysis, or LRA). The analyses revealed that canines were the most sexually dimorphic teeth followed by molars. All tooth variables were larger in males, with 51/56 (91.1%) being statistically larger (p < 0.05). When the stepwise LRA formulae were applied to a test sample of 69 subjects (40 females, 29 males) of the same age range, allocation accuracy of 68.1% for the maxillary teeth, 73.9% for the mandibular teeth, and 71% for teeth of both jaws combined, were obtained. The high univariate sexual dimorphism observed herein contrasts with some reports of low, and sometimes reverse, sexual dimorphism (the phenomenon of female tooth dimensions being larger than males'); the LRA results, too, are in contradiction to a previous report of virtually 100% sex allocation for a small heterogeneous sample. These reflect the importance of using a large sample to quantify sexual dimorphism in tooth dimensions and the application of the derived formulae on a test dataset to ascertain accuracy which, at best, is moderate in nature.

  4. Understanding sexual orientation health disparities in smoking: a population-based analysis.

    PubMed

    Balsam, Kimberly F; Beadnell, Blair; Riggs, Karin R

    2012-10-01

    Lesbian, gay, and bisexual populations are at elevated risk for tobacco use compared to their heterosexual peers. However, there is little research examining reasons for this disparity. Drawing on prior literature regarding psychosocial variables associated with both sexual orientation and smoking, the authors tested a path model of risk and protective factors to help explain sexual orientation differences in smoking using data from the Washington State Behavioral Risk Factor Surveillance System from 2003 to 2007. The authors estimated separate models for men and women, comparing lesbians or gays and bisexuals to heterosexuals. Results indicated that the explanatory variables accounted for most of the variance in this relationship, with both risk-enhancing and risk-reducing pathways. Mental health, life dissatisfaction, alcohol use, exposure to tobacco marketing, and single relationship status were risk enhancers for most LGB participants. Health-care access and income level were risk enhancers for bisexual participants only. Neither emotional support nor attitudes and knowledge about tobacco use helped explain the relationship between sexual orientation and smoking. These findings have significant implications for tobacco prevention and control efforts in this high-risk population.

  5. Talus measurements as a diagnostic tool for sexual dimorphism in Egyptian population.

    PubMed

    Abd-elaleem, Shereen Abd-elhakim; Abd-elhameed, Mostafa; Ewis, Ashraf Abd-elazeem

    2012-02-01

    Measurements of talus have been shown to be sexually dimorphic in South African blacks and whites and Prehistoric New Zealand Polynesians. Since several studies have demonstrated that discriminant function equations used to determine the sex of a skeleton are population specific, the purpose of the present study was to derive similar equation for the tali of Egyptians. The sample consisted of 110 tali (67 male & 43 female) whose age at death ranged between 20 and 60 years. The tali were obtained from Anatomy departments of Minia and Cairo Universities and also from Forensic Medicine department of Justice Office in Minia governates - Egypt. Twelve measurements were taken for every talus. Data were analyzed by SPSS version 16. All measurements showed significant sexual differences (P < 0.05) except calcaneus articular surface width and navicular articular surfaced width. Talar length was found to be the most sexual dimorphic (90.9%). Combination of talar length, talar width and neck width gave a percentage of accuracy of 85.5%. Finally, it is concluded that the talus of Egyptian population is useful for sex estimation.

  6. The maintenance of sex, clonal dynamics, and host-parasite coevolution in a mixed population of sexual and asexual snails.

    PubMed

    Jokela, Jukka; Dybdahl, Mark F; Lively, Curtis M

    2009-07-01

    Sexual populations should be vulnerable to invasion and replacement by ecologically similar asexual females because asexual lineages have higher per capita growth rates. However, as asexual genotypes become common, they may also become disproportionately infected by parasites. The Red Queen hypothesis postulates that high infection rates in the common asexual clones could periodically favor the genetically diverse sexual individuals and promote the short-term coexistence of sexual and asexual populations. Testing this idea requires comparison of competing sexual and asexual lineages that are attacked by natural parasites. To date no such data have been available. Here, we report on long-term dynamics and parasite coevolution in a "mixed" (sexual and asexual) population of snails (Potamopyrgus antipodarum). We found that, within 7-10 years, the most common clones were almost completely replaced by initially rare clones in two different habitats, while sexuals persisted throughout the study period. The common clones, which were initially more resistant to infection, also became more susceptible to infection by sympatric (but not allopatric) parasites over the course of the study. These results are consistent with the Red Queen hypothesis and show that the coevolutionary dynamics predicted by the theory may also favor sexual reproduction in natural populations.

  7. Population genetic analysis of large sequence polymorphisms in Plasmodium falciparum blood-stage antigens.

    PubMed

    Ahouidi, Ambroise D; Bei, Amy K; Neafsey, Daniel E; Sarr, Ousmane; Volkman, Sarah; Milner, Dan; Cox-Singh, Janet; Ferreira, Marcelo U; Ndir, Omar; Premji, Zul; Mboup, Souleymane; Duraisingh, Manoj T

    2010-03-01

    Plasmodium falciparum, the causative agent of human malaria, invades host erythrocytes using several proteins on the surface of the invasive merozoite, which have been proposed as potential vaccine candidates. Members of the multi-gene PfRh family are surface antigens that have been shown to play a central role in directing merozoites to alternative erythrocyte receptors for invasion. Recently, we identified a large structural polymorphism, a 0.58Kb deletion, in the C-terminal region of the PfRh2b gene, present at a high frequency in parasite populations from Senegal. We hypothesize that this region is a target of humoral immunity. Here, by analyzing 371 P. falciparum isolates we show that this major allele is present at varying frequencies in different populations within Senegal, Africa, and throughout the world. For allelic dimorphisms in the asexual stage antigens, Msp-2 and EBA-175, we find minimal geographic differentiation among parasite populations from Senegal and other African localities, suggesting extensive gene flow among these populations and/or immune-mediated frequency-dependent balancing selection. In contrast, we observe a higher level of inter-population divergence (as measured by F(st)) for the PfRh2b deletion, similar to that observed for SNPs from the sexual stage Pfs45/48 loci, which is postulated to be under directional selection. We confirm that the region containing the PfRh2b polymorphism is a target of humoral immune responses by demonstrating antibody reactivity of endemic sera. Our analysis of inter-population divergence suggests that in contrast to the large allelic dimorphisms in EBA-175 and Msp-2, the presence or absence of the large PfRh2b deletion may not elicit frequency-dependent immune selection, but may be under positive immune selection, having important implications for the development of these proteins as vaccine candidates.

  8. The large X-effect on secondary sexual characters and the genetics of variation in sex comb tooth number in Drosophila subobscura.

    PubMed

    Mittleman, Briana E; Manzano-Winkler, Brenda; Hall, Julianne B; Korunes, Katharine L; Noor, Mohamed A F

    2017-01-01

    Genetic studies of secondary sexual traits provide insights into whether and how selection drove their divergence among populations, and these studies often focus on the fraction of variation attributable to genes on the X-chromosome. However, such studies may sometimes misinterpret the amount of variation attributable to the X-chromosome if using only simple reciprocal F1 crosses, or they may presume sexual selection has affected the observed phenotypic variation. We examined the genetics of a secondary sexual trait, male sex comb size, in Drosophila subobscura. This species bears unusually large sex combs for its species group, and therefore, this trait may be a good candidate for having been affected by natural or sexual selection. We observed significant heritable variation in number of teeth of the distal sex comb across strains. While reciprocal F1 crosses seemed to implicate a disproportionate X-chromosome effect, further examination in the F2 progeny showed that transgressive autosomal effects inflated the estimate of variation associated with the X-chromosome in the F1. Instead, the X-chromosome appears to confer the smallest contribution of all major chromosomes to the observed phenotypic variation. Further, we failed to detect effects on copulation latency or duration associated with the observed phenotypic variation. Overall, this study presents an examination of the genetics underlying segregating phenotypic variation within species and illustrates two common pitfalls associated with some past studies of the genetic basis of secondary sexual traits.

  9. Structural stigma and all-cause mortality in sexual minority populations.

    PubMed

    Hatzenbuehler, Mark L; Bellatorre, Anna; Lee, Yeonjin; Finch, Brian K; Muennig, Peter; Fiscella, Kevin

    2014-02-01

    Stigma operates at multiple levels, including intrapersonal appraisals (e.g., self-stigma), interpersonal events (e.g., hate crimes), and structural conditions (e.g., community norms, institutional policies). Although prior research has indicated that intrapersonal and interpersonal forms of stigma negatively affect the health of the stigmatized, few studies have addressed the health consequences of exposure to structural forms of stigma. To address this gap, we investigated whether structural stigma-operationalized as living in communities with high levels of anti-gay prejudice-increases risk of premature mortality for sexual minorities. We constructed a measure capturing the average level of anti-gay prejudice at the community level, using data from the General Social Survey, which was then prospectively linked to all-cause mortality data via the National Death Index. Sexual minorities living in communities with high levels of anti-gay prejudice experienced a higher hazard of mortality than those living in low-prejudice communities (Hazard Ratio [HR] = 3.03, 95% Confidence Interval [CI] = 1.50, 6.13), controlling for individual and community-level covariates. This result translates into a shorter life expectancy of approximately 12 years (95% C.I.: 4-20 years) for sexual minorities living in high-prejudice communities. Analysis of specific causes of death revealed that suicide, homicide/violence, and cardiovascular diseases were substantially elevated among sexual minorities in high-prejudice communities. Strikingly, there was an 18-year difference in average age of completed suicide between sexual minorities in the high-prejudice (age 37.5) and low-prejudice (age 55.7) communities. These results highlight the importance of examining structural forms of stigma and prejudice as social determinants of health and longevity among minority populations.

  10. Structural Stigma and All-Cause Mortality in Sexual Minority Populations

    PubMed Central

    Hatzenbuehler, Mark L.; Bellatorre, Anna; Lee, Yeonjin; Finch, Brian; Muennig, Peter; Fiscella, Kevin

    2013-01-01

    Stigma operates at multiple levels, including intrapersonal appraisals (e.g., self-stigma), interpersonal events (e.g., hate crimes), and structural conditions (e.g., community norms, institutional policies). Although prior research has indicated that intrapersonal and interpersonal forms of stigma negatively affect the health of the stigmatized, few studies have addressed the health consequences of exposure to structural forms of stigma. To address this gap, we investigated whether structural stigma—operationalized as living in communities with high levels of anti-gay prejudice—increases risk of premature mortality for sexual minorities. We constructed a measure capturing the average level of anti-gay prejudice at the community level, using data from the General Social Survey, which was then prospectively linked to all-cause mortality data via the National Death Index. Sexual minorities living in communities with high levels of anti-gay prejudice experienced a higher hazard of mortality than those living in low-prejudice communities (Hazard Ratio [HR] =3.03, 95% Confidence Interval [CI]=1.50, 6.13), controlling for individual and community-level covariates. This result translates into a shorter life expectancy of approximately 12 years (95% C.I.: 4-20 years) for sexual minorities living in high-prejudice communities. Analysis of specific causes of death revealed that suicide, homicide/violence, and cardiovascular diseases were substantially elevated among sexual minorities in high-prejudice communities. Strikingly, there was an 18-year difference in average age of completed suicide between sexual minorities in the high-prejudice (age 37.5) and low-prejudice (age 55.7) communities. These results highlight the importance of examining structural forms of stigma and prejudice as social determinants of health and longevity among minority populations. PMID:23830012

  11. Evaluation of sexuality in a Paraguayan mid-aged female urban population using the six-item Female Sexual Function Index.

    PubMed

    Sánchez, S C; Chedraui, P; Pérez-López, F R; Ortiz-Benegas, M E; Palacios-De Franco, Y

    2016-06-01

    Background There are scant data related to sexuality assessed among mid-aged women from Paraguay. Objective To assess sexual function in a sample of mid-aged Paraguayan women. Methods This was a cross-sectional study in which 265 urban-living women from Asunción (Paraguay) aged 40-65 years were surveyed with the six-item version of the Female Sexual Function Index (FSFI-6) and a questionnaire containing personal and partner data. Results The median age of the sample was 48 years, 48.2% were postmenopausal (median/interquartile range age at menopause 46/13 years), 11.3% used hormone therapy, 37.0% used psychotropic drugs, 44.5% had hypertension, 7.2% diabetes, 46.1% abdominal obesity and 89.4% had a partner (n = 237). Overall, 84.1% (223/265) of surveyed women were sexually active, presenting a median total FSFI-6 score of 23.0, and 25.6% obtained a total score of 19 or less, suggestive of sexual dysfunction (lower sexual function). Upon bivariate analysis, several factors were associated with lower total FSFI-6 scores; however, multiple linear regression analysis found that lower total FSFI-6 scores (worse sexual function) were significantly correlated to the postmenopausal status and having an older partner, whereas coital frequency was positively correlated to higher scores (better sexual function). Conclusion In this pilot sample of urban-living, mid-aged Paraguayan women, as determined with the FSFI-6, lower sexual function was related to menopausal status, coital frequency and partner age. There is a need for more research in this regard in this population.

  12. Epidemiology of sexually transmitted infections in global indigenous populations: data availability and gaps.

    PubMed

    Minichiello, Victor; Rahman, Saifur; Hussain, Rafat

    2013-10-01

    Socioeconomic and health disadvantage is widespread within and across indigenous communities in the world, leading to differentials in morbidity and mortality between indigenous and non-indigenous populations. Sexually transmitted infections (STIs), including HIV/AIDS, among indigenous populations are an emerging public health concern. The focus of this paper is on examining the STI epidemiology in indigenous communities in various parts of the world utilizing a range of data sources. Most of the STI research on global indigenous communities has concentrated on developed countries, neglecting more than half the world's indigenous people in the developing countries. This has resulted in major gaps in data at global level for STIs and HIV/AIDS among indigenous populations. Available data show that the prevalence of STIs is increasing among the indigenous communities and in several instances, the rates of these infections are higher than among non-indigenous populations. However, HIV still remains low when compared with the rates of other STIs. The paper argues that there is an urgent need to collect more comprehensive and reliable data at the global level across various indigenous communities. There is also an opportunity to reverse current trends in STIs through innovative, evidence-based and culturally appropriate targeted sexual health programmes.

  13. Comparison of sexual assaults by strangers and known assailants in an urban population of women.

    PubMed Central

    Stermac, L E; Du Mont, J A; Kalemba, V

    1995-01-01

    OBJECTIVE: To examine the characteristics of sexual assaults by strangers and those by people known to the victims in an urban community-based population of women. DESIGN: Descriptive study. SETTING: Sexual Assault Care Centre, Women's College Hospital, Toronto. PARTICIPANTS: All 677 women who presented to the centre between June 1, 1991, and Sept. 30, 1993, and for whom the victim-assailant relationship was known. OUTCOME MEASURES: Assailant's relationship to victim, sex of assailant, number of assailants, number, type and location of assaults, use of weapons, type of coercion and extent of physical trauma or injury. RESULTS: Sexual assault by a person known to the victim accounted for 456 (67.4%) of the assaults reported. In 344 cases the person was known more than 24 hours; 99 (28.8%) were current or previous boyfriends or spouses. Assailants who were strangers were more likely to assault the victim more than once (t = -2.42, 355 degrees of freedom [df], p < 0.05), force the victim to perform fellatio (chi 2 = 8.63, 1 df, p < 0.005), use weapons (chi 2 = 12.01, 1 df, p < 0.001) and use physical coercion (chi 2 = 4.42, 1 df, p < 0.05), whereas assailants who were known to the victims were more likely to assault a woman who was sleeping or drugged (chi 2 = 10.38, 1 df, p < 0.005). Sexual assault by a known assailant was more likely to occur in the home of the victim (chi 2 = 36.27, 1 df, p < 0.001) or the assailant (chi 2 = 8.46, 1 df, p < 0.005), whereas sexual assault by a stranger was more likely to occur outdoors (chi 2 = 89.80, 1 df, p < 0.001) or in a vehicle (chi 2 = 32.81, 1 df, p < 0.001). Overall, the mean number of trauma sites was greater among victims assaulted by strangers than among those assaulted by people they knew (t = -4.29, 180 df, p < 0.001). CONCLUSION: Two thirds of the sexual assaults in this urban population were committed by people known to the victims, and over two thirds of these assaults were associated with physical trauma. Improved

  14. Protocol Design for Large-Scale Cross-Sectional Studies of Sexual Abuse and Associated Factors in Individual Sports: Feasibility Study in Swedish Athletics

    PubMed Central

    Timpka, Toomas; Janson, Staffan; Jacobsson, Jenny; Ekberg, Joakim; Dahlström, Örjan; Kowalski, Jan; Bargoria, Victor; Mountjoy, Margo; Svedin, Carl G.

    2015-01-01

    research protocol for cross-sectional epidemiological studies of sexual abuse in athletics was designed and its feasibility evaluated. The definition of sexual abuse, ethical soundness of the protocol, reference populations and study of co-morbidity, and means for athlete-level data collection were in requirements analyses identified as particularly complex design issues. The feasibility evaluation showed a high non-participation rate (61%), but also that the large majority of participants found the study important and that questions were answered truthfully. Responding that partaking in the study was not personally gratifying was associated with training more hours. When implementing cross-sectional epidemiological studies of sexual abuse in athletics, it is necessary to promote and facilitate athlete participation. PMID:25729306

  15. Protocol design for large-scale cross-sectional studies of sexual abuse and associated factors in individual sports: feasibility study in Swedish athletics.

    PubMed

    Timpka, Toomas; Janson, Staffan; Jacobsson, Jenny; Ekberg, Joakim; Dahlström, Örjan; Kowalski, Jan; Bargoria, Victor; Mountjoy, Margo; Svedin, Carl G

    2015-03-01

    A research protocol for cross-sectional epidemiological studies of sexual abuse in athletics was designed and its feasibility evaluated.The definition of sexual abuse, ethical soundness of the protocol, reference populations and study of co-morbidity, and means for athlete-level data collection were in requirements analyses identified as particularly complex design issues.The feasibility evaluation showed a high non-participation rate (61%), but also that the large majority of participants found the study important and that questions were answered truthfully.Responding that partaking in the study was not personally gratifying was associated with training more hours.When implementing cross-sectional epidemiological studies of sexual abuse in athletics, it is necessary to promote and facilitate athlete participation.

  16. Gender moderates the relationship between impulsivity and sexual risk-taking in a cocaine-using psychiatric outpatient population.

    PubMed

    Black, Anne C; McMahon, Thomas J; Potenza, Marc N; Fiellin, Lynn E; Rosen, Marc I

    2015-03-01

    Adults who abuse substances are at increased risk for contracting sexually transmitted infections, including HIV. Within this population, sexual risk behaviors have been associated with increased impulsivity. Studies in non-clinical populations showing gender-related differences in sexual decision-making and casual sexual partnering suggest impulsivity has a greater influence on men than women, but these differences have not been documented in substance-using patients. In a sample of 89 adults with recent cocaine use and receiving outpatient psychiatric treatment, we tested the hypothesis that gender moderates the effect of impulsivity on sexual risk-taking. Using logistic regression modeling, we tested the main and gender-moderated effects of task-related impulsivity on the probability of having a casual sexual partner and multiple sexual partners. Results confirmed a significant gender-by-impulsivity interaction; men who were more impulsive on a continuous performance task had significantly higher rates of sexual risk-taking than less impulsive men, but women's impulsivity was unrelated to these outcomes. Impulsive men were over three times as likely as less impulsive men to have a recent casual partner. Implications of these results and suggestions for future research are discussed.

  17. Gender moderates the relationship between impulsivity and sexual risk-taking in a cocaine-using psychiatric outpatient population

    PubMed Central

    Black, Anne C.; McMahon, Thomas J.; Potenza, Marc N.; Fiellin, Lynn E.; Rosen, Marc I.

    2014-01-01

    Adults who abuse substances are at increased risk for contracting sexually transmitted infections, including HIV. Within this population, sexual risk behaviors have been associated with increased impulsivity. Studies in non-clinical populations showing gender-related differences in sexual decision-making and casual sexual partnering suggest impulsivity has a greater influence on men than women, but these differences have not been documented in substance-using patients. In a sample of 89 adults with recent cocaine use and receiving outpatient psychiatric treatment, we tested the hypothesis that gender moderates the effect of impulsivity on sexual risk-taking. Using logistic regression modeling, we tested the main and gender-moderated effects of task-related impulsivity on the probability of having a casual sexual partner and multiple sexual partners. Results confirmed a significant gender-by-impulsivity interaction; men who were more impulsive on a continuous performance task had significantly higher rates of sexual risk-taking than less impulsive men, but women's impulsivity was unrelated to these outcomes. Impulsive men were over three times as likely as less impulsive men to have a recent casual partner. Implications of these results and suggestions for future research are discussed. PMID:25554716

  18. Argentine Population Genetic Structure: Large Variance in Amerindian Contribution

    PubMed Central

    Seldin, Michael F.; Tian, Chao; Shigeta, Russell; Scherbarth, Hugo R.; Silva, Gabriel; Belmont, John W.; Kittles, Rick; Gamron, Susana; Allevi, Alberto; Palatnik, Simon A.; Alvarellos, Alejandro; Paira, Sergio; Caprarulo, Cesar; Guillerón, Carolina; Catoggio, Luis J.; Prigione, Cristina; Berbotto, Guillermo A.; García, Mercedes A.; Perandones, Carlos E.; Pons-Estel, Bernardo A.; Alarcon-Riquelme, Marta E.

    2011-01-01

    Argentine population genetic structure was examined using a set of 78 ancestry informative markers (AIMs) to assess the contributions of European, Amerindian, and African ancestry in 94 individuals members of this population. Using the Bayesian clustering algorithm STRUCTURE, the mean European contribution was 78%, the Amerindian contribution was 19.4%, and the African contribution was 2.5%. Similar results were found using weighted least mean square method: European, 80.2%; Amerindian, 18.1%; and African, 1.7%. Consistent with previous studies the current results showed very few individuals (four of 94) with greater than 10% African admixture. Notably, when individual admixture was examined, the Amerindian and European admixture showed a very large variance and individual Amerindian contribution ranged from 1.5 to 84.5% in the 94 individual Argentine subjects. These results indicate that admixture must be considered when clinical epidemiology or case control genetic analyses are studied in this population. Moreover, the current study provides a set of informative SNPs that can be used to ascertain or control for this potentially hidden stratification. In addition, the large variance in admixture proportions in individual Argentine subjects shown by this study suggests that this population is appropriate for future admixture mapping studies. PMID:17177183

  19. Host sexual selection and cuckoo parasitism: an analysis of nest size in sympatric and allopatric magpie Pica pica populations parasitized by the great spotted cuckoo Clamator glandarius

    PubMed Central

    Soler, J. J.; nez, J. G. Mart; Soler, M.; ller, A. P. M

    1999-01-01

    Magpies (Pica pica) build large nests that are the target of sexual selection, since males of early breeding pairs provide many sticks for nests and females mated to such males enjoy a material fitness benefit in terms of better quality territory and parental care of superior quality. Great spotted cuckoos (Clamator glandarius) preferentially parasitize large magpie nests and sexual selection for large nests is thus opposed by natural selection due to brood parasitism. Consistent with the hypothesized opposing selection pressures, in a comparative analysis of 14 magpie populations in Europe we found that nest volume was consistently smaller in sympatry than in allopatry with the great spotted cuckoo, in particular in areas with a high parasitism rate and high rates of rejection of mimetic model cuckoo eggs. These observations are consistent with the suggestion that magpies have evolved a smaller nest size in areas where cuckoos have exerted strong selection pressures on them in the recent past.

  20. Changes and Correlates in Multiple Sexual Partnerships among Chinese Adult Women——Population Based Surveys in 2000 and 2006

    PubMed Central

    Yingying, Huang; Smith, Kumi; Suiming, Pan

    2011-01-01

    The sexual transmission of HIV and STI is becoming a major public health concern in China. However, studies on sexuality in China remain scant, particularly those that analyze female sexuality. This study is to investigate the prevalence of multiple sexual partnerships among adult women, and to examine trends and correlates for having more than one lifetime sexual partner. Multiple sexual partnership (MSP), coded as having one or none vs. two or more lifetime sexual partners, was the key binary outcome measure. The data were from two national probability surveys on sexual behaviors in China carried out in 2000 and 2006. The sample size of adult women was 1899 in 2000 (total sample n= 3812), and 2626 in 2006 (n=5404). Overall prevalence of MSP increased from 8.1% in 2000 to 29.6% in 2006 (Chi-square test, sig.=0.000). The most rapid changes took place among women with less education, those who worked in blue collar jobs and lower social status positions, and those living in rural areas or small towns. Women who were better educated, lived in big cities, and held management level occupations exhibited less change but had a higher baselines prevalence of MSP, suggesting that changes in MSP behavior may occur initially among women of higher socioeconomic status. Based on the 2006 dataset, significant positive correlates of MSP included more years of education, being in a long-term relationship, being middle aged, having a lower status job, going out dancing at entertainments venues, and being a state of overall health in the past 12 months. The significant recent increase in MSP among women reinforces the need to examine China’s sexual revolution in the context of a rapidly transitioning society. Findings regarding female sexuality also raise new questions to be explored in further sexuality studies, in order to better understand population sexual behaviors and to inform future HIV prevention efforts. PMID:21660755

  1. Prevalence and predictors of concurrent sexual partnerships in a predominantly African American population in Jackson, Mississippi

    PubMed Central

    Nunn, Amy; MacCarthy, Sarah; Barnett, Nancy; Rose, Jennifer; Chan, Philip; Yolken, Annajane; Cornwall, Alexandra; Chamberlain, Nicholas; Barnes, Arti; Riggins, Reginald; Moore, Elya; Simmons, Dantrell; Parker, Sharon; Mena, Leandro

    2014-01-01

    Concurrent sexual partnerships, or sexual partnerships that overlap in time, have been associated with HIV and sexually transmitted infections (STI) infection. How best to measure concurrency and the personal characteristics and predictors of concurrency are not yet well understood. We compared two frequently used concurrency definitions, including a self-reported measure based on participant response regarding overlapping sex with partners, and the UNAIDS measure based on overlapping dates of last sex and intention to have sex again. We performed multivariable logistic regression analyses to identify socio-demographic, behavioral, and structural predictors of concurrency among 1,542 patients at an urban STI clinic in Jackson, Mississippi. Nearly half (44%) reported concurrency based on self-reported sex with other partners, and 26% reported concurrency according to the UNAIDS concurrency measure. Using the self-reported concurrency measure, the strongest predictors of concurrency were perceived partner concurrency, drug use at last sex, having more than 10 lifetime partners, and being recently incarcerated. Strongest predictors of concurrency using the UNAIDS measure were lifetime number of partners and perceived partner concurrency. Concurrency is highly prevalent in this population in the Deep South and social, structural and behavioral factors were important predictors of concurrency for both measures. Future research should use time anchored data collection methods and biomarkers to assess whether both definitions of concurrency are associated with HIV outcomes. PMID:24803130

  2. Food choice behaviour may promote habitat specificity in mixed populations of clonal and sexual Potamopyrgus antipodarum.

    PubMed

    Negovetic; Jokela

    2000-10-01

    Genetic polymorphism along an environmental gradient may be maintained if disruptive selection on habitat-specific traits leads to a correlated response in traits that reduce gene flow between habitats. We studied a short-distance cline in a population of freshwater snails Potamopyrgus antipodarum in which sexual and clonal snails coexist. Sexuals and clones show a life history cline by depth: snails reproduce at a smaller size in shallower habitats. Clones are also structured genetically across habitats and seem not to mix, even though habitats are within the dispersal distance of the snails and the opportunity for gene flow via migration must be considerable. Because habitat preference may promote divergence in both clones and sexuals along the depth gradient, we investigated whether snails show habitat-specific food choice behaviour that could reduce migration. We tested the food choice behaviour of the snails by exposing them simultaneously to food from their home and adjacent habitats. Both juvenile and adult snails from the shallow shore bank and a mid-water macrophyte habitat preferentially grazed on the vegetation of their original habitats. We suggest that the observed genetic and life history cline may be maintained by food choice behaviour that may promote a partial barrier to gene flow between the habitats. Copyright 2000 The Association for the Study of Animal Behaviour.

  3. Influence of breeding habitat on bear predation and age at maturity and sexual dimorphism of sockeye salmon populations

    USGS Publications Warehouse

    Quinn, Thomas P; Wetzel, Lisa A.; Bishop, Susan; Overberg, Kristi; Rogers, Donald E.

    2001-01-01

    Age structure and morphology differ among Pacific salmon (Oncorhynchus spp.) populations. Sexual selection and reproductive capacity (fecundity and egg size) generally favor large (old), deep-bodied fish. We hypothesized that natural selection from physical access to spawning grounds and size-biased predation by bears, Ursus spp., opposes such large, deep-bodied salmon. Accordingly, size and shape of salmon should vary predictably among spawning habitats. We tested this hypothesis by measuring the age composition and body depth of sockeye salmon, Oncorhynchus nerka, and the intensity of predation in a range of breeding habitats in southwestern Alaska. Stream width was positively correlated with age at maturity and negatively correlated with predation level. However, salmon spawning on lake beaches were not consistently old, indicating that different factors affect age in riverine- and beach-spawning populations. Body depths of male and female salmon were positively correlated with water depth across all sites, as predicted. However, the mouths of some streams were so shallow that they might select against large or deep-bodied salmon, even in the absence of bear predation. Taken together, the results indicated that habitat has direct and indirect effects (via predation) on life history and morphology of mature salmon.

  4. Genome size variation affects song attractiveness in grasshoppers: evidence for sexual selection against large genomes.

    PubMed

    Schielzeth, Holger; Streitner, Corinna; Lampe, Ulrike; Franzke, Alexandra; Reinhold, Klaus

    2014-12-01

    Genome size is largely uncorrelated to organismal complexity and adaptive scenarios. Genetic drift as well as intragenomic conflict have been put forward to explain this observation. We here study the impact of genome size on sexual attractiveness in the bow-winged grasshopper Chorthippus biguttulus. Grasshoppers show particularly large variation in genome size due to the high prevalence of supernumerary chromosomes that are considered (mildly) selfish, as evidenced by non-Mendelian inheritance and fitness costs if present in high numbers. We ranked male grasshoppers by song characteristics that are known to affect female preferences in this species and scored genome sizes of attractive and unattractive individuals from the extremes of this distribution. We find that attractive singers have significantly smaller genomes, demonstrating that genome size is reflected in male courtship songs and that females prefer songs of males with small genomes. Such a genome size dependent mate preference effectively selects against selfish genetic elements that tend to increase genome size. The data therefore provide a novel example of how sexual selection can reinforce natural selection and can act as an agent in an intragenomic arms race. Furthermore, our findings indicate an underappreciated route of how choosy females could gain indirect benefits.

  5. Surrogate population models for large-scale neural simulations.

    PubMed

    Tripp, Bryan P

    2015-06-01

    Because different parts of the brain have rich interconnections, it is not possible to model small parts realistically in isolation. However, it is also impractical to simulate large neural systems in detail. This article outlines a new approach to multiscale modeling of neural systems that involves constructing efficient surrogate models of populations. Given a population of neuron models with correlated activity and with specific, nonrandom connections, a surrogate model is constructed in order to approximate the aggregate outputs of the population. The surrogate model requires less computation than the neural model, but it has a clear and specific relationship with the neural model. For example, approximate spike rasters for specific neurons can be derived from a simulation of the surrogate model. This article deals specifically with neural engineering framework (NEF) circuits of leaky-integrate-and-fire point neurons. Weighted sums of spikes are modeled by interpolating over latent variables in the population activity, and linear filters operate on gaussian random variables to approximate spike-related fluctuations. It is found that the surrogate models can often closely approximate network behavior with orders-of-magnitude reduction in computational demands, although there are certain systematic differences between the spiking and surrogate models. Since individual spikes are not modeled, some simulations can be performed with much longer steps sizes (e.g., 20 ms). Possible extensions to non-NEF networks and to more complex neuron models are discussed.

  6. Response of human populations to large-scale emergencies

    NASA Astrophysics Data System (ADS)

    Bagrow, James; Wang, Dashun; Barabási, Albert-László

    2010-03-01

    Until recently, little quantitative data regarding collective human behavior during dangerous events such as bombings and riots have been available, despite its importance for emergency management, safety and urban planning. Understanding how populations react to danger is critical for prediction, detection and intervention strategies. Using a large telecommunications dataset, we study for the first time the spatiotemporal, social and demographic response properties of people during several disasters, including a bombing, a city-wide power outage, and an earthquake. Call activity rapidly increases after an event and we find that, when faced with a truly life-threatening emergency, information rapidly propagates through a population's social network. Other events, such as sports games, do not exhibit this propagation.

  7. Constraints on Intervening Stellar Populations toward the Large Magellanic Cloud

    NASA Astrophysics Data System (ADS)

    Zaritsky, Dennis; Shectman, Stephen A.; Thompson, Ian; Harris, Jason; Lin, D. N. C.

    1999-05-01

    The suggestion by Zaritsky & Lin (ZL) that a vertical extension of the red clump feature (the VRC) in color-magnitude diagrams (CMDs) of the Large Magellanic Cloud is consistent with a significant population of foreground stars to the LMC that could account for the observed microlensing optical depth has been challenged by various investigators. We respond by (1) examining each of the challenges presented, to determine whether any or all of those arguments invalidate the claims made by ZL, and (2) presenting new photometric and spectroscopic data obtained in an attempt to resolve this issue. We systematically discuss why the objections raised so far do not unequivocally refute ZL's claim. We conclude that although the CMD data do not mandate the existence of a foreground population, they are entirely consistent with a foreground population associated with the LMC that contributes significantly (~50%) to the observed microlensing optical depth. From our new data, we conclude that <~40% of the VRC stars are young, massive red clump stars, because (1) synthetic CMDs created using the star formation history derived independently from Hubble Space Telescope data suggest that fewer than 50% of the VRC stars are young, massive red clump stars, (2) the angular distribution of the VRC stars is more uniform than that of the young (<1 Gyr) main-sequence stars, and (3) the velocity dispersion of the VRC stars in the region of the LMC examined by ZL, 18.4+/-2.8 km s^-1 (95% confidence limits), is inconsistent with the expectation for a young disk population. Each of these arguments is predicated on assumptions, and the conclusions are uncertain. Therefore, an exact determination of the contribution to the microlensing optical depth by the various hypothesized foreground populations, and the subsequent conclusions regarding the existence of halo MACHOs, requires a detailed knowledge of many complex astrophysical issues, such as the initial mass function, star formation history

  8. Mating-type distribution and genetic diversity of Cercospora sojina populations on soybean from Arkansas: evidence for potential sexual reproduction.

    PubMed

    Kim, Hun; Newell, Annakay D; Cota-Sieckmeyer, Robyn G; Rupe, John C; Fakhoury, Ahmad M; Bluhm, Burton H

    2013-10-01

    Cercospora sojina causes frogeye leaf spot of soybean, which can cause serious economic losses in the United States. In this study, 132 C. sojina isolates were collected from six fields (from two counties, Cross and Crawford) in Arkansas. To determine mating type, a multiplex polymerase chain reaction assay was developed with primers specific for C. sojina. Of the 132 isolates, 68 isolates had the MAT1-1-1 idiomorph and 64 isolates had the MAT1-2 idiomorph; no isolates possessed both idiomorphs. Both mating types were present in a variety of spatial scales, including separate lesions on individual leaves. Clone-corrected data from eight microsatellites indicated that mating-type loci were present in approximately equal proportions in all populations analyzed, which suggests that Arkansas populations of C. sojina are undergoing cryptic sexual reproduction. All six populations evaluated had high genotypic diversity of 26 to 79%. In addition, among strains isolated from a single leaf, multiple and distinct haplotypes were associated with both mating types, supporting the hypothesis that sexual reproduction occurs within the populations. Most populations showed significant gametic disequilibrium but levels of disequilibrium were relatively low, particularly in populations from Crawford County. A low differentiation index (GST) was observed for all simple-sequence repeat markers across all populations. Furthermore, the value of G statistics between populations suggests that significant genetic exchange exists among the populations. Taken together, these results demonstrate that C. sojina populations from Arkansas are genetically diverse and most likely undergoing sexual reproduction.

  9. Large-scale MHC class II genotyping of a wild lemur population by next generation sequencing.

    PubMed

    Huchard, Elise; Albrecht, Christina; Schliehe-Diecks, Susanne; Baniel, Alice; Roos, Christian; Kappeler, Peter M; Peter, Peter M Kappeler; Brameier, Markus

    2012-12-01

    The critical role of major histocompatibility complex (MHC) genes in disease resistance, along with their putative function in sexual selection, reproduction and chemical ecology, make them an important genetic system in evolutionary ecology. Studying selective pressures acting on MHC genes in the wild nevertheless requires population-wide genotyping, which has long been challenging because of their extensive polymorphism. Here, we report on large-scale genotyping of the MHC class II loci of the grey mouse lemur (Microcebus murinus) from a wild population in western Madagascar. The second exons from MHC-DRB and -DQB of 772 and 672 individuals were sequenced, respectively, using a 454 sequencing platform, generating more than 800,000 reads. Sequence analysis, through a stepwise variant validation procedure, allowed reliable typing of more than 600 individuals. The quality of our genotyping was evaluated through three independent methods, namely genotyping the same individuals by both cloning and 454 sequencing, running duplicates, and comparing parent-offspring dyads; each displaying very high accuracy. A total of 61 (including 20 new) and 60 (including 53 new) alleles were detected at DRB and DQB genes, respectively. Both loci were non-duplicated, in tight linkage disequilibrium and in Hardy-Weinberg equilibrium, despite the fact that sequence analysis revealed clear evidence of historical selection. Our results highlight the potential of 454 sequencing technology in attempts to investigate patterns of selection shaping MHC variation in contemporary populations. The power of this approach will nevertheless be conditional upon strict quality control of the genotyping data.

  10. Macroecology of Sexual Selection: A Predictive Conceptual Framework for Large-Scale Variation in Reproductive Traits.

    PubMed

    Machado, Glauco; Buzatto, Bruno A; García-Hernández, Solimary; Macías-Ordóñez, Rogelio

    2016-09-01

    Abiotic factors exert direct and indirect influences on behavioral, morphological, and life-history traits. Because some of these traits are related to reproduction, there is a causal link between climatic conditions and the expression of reproductive traits. This link allows us to generate predictions on how reproductive traits vary in large geographic scales. Here we formalize this macroecological framework, present some general predictions, and explore empirical examples using harvestmen as study organisms. Our results show that the length of breeding season in harvestmen is primarily influenced by the number of warm months and that precipitation plays a secondary role in modulating the period devoted to reproduction. Moreover, we show that the probability of resource defense polygyny increases with longer breeding seasons and that the presence of this type of mating system positively affects the magnitude of sexual dimorphism in harvestmen. Finally, the presence of postovipositional parental care is also influenced by the length of breeding season but not by actual evapotranspiration, which is our proxy for the intensity of biotic interactions. We argue that the macroecological framework proposed here may be a fruitful field of investigation, with important implications for our understanding of sexual selection and the evolution of reproductive traits in both animals and plants.

  11. Sexual selection and population divergence I: The influence of socially flexible cuticular hydrocarbon expression in male field crickets (Teleogryllus oceanicus).

    PubMed

    Pascoal, Sonia; Mendrok, Magdalena; Mitchell, Christopher; Wilson, Alastair J; Hunt, John; Bailey, Nathan W

    2016-01-01

    Debates about how coevolution of sexual traits and preferences might promote evolutionary diversification have permeated speciation research for over a century. Recent work demonstrates that the expression of such traits can be sensitive to variation in the social environment. Here, we examined social flexibility in a sexually selected male trait-cuticular hydrocarbon (CHC) profiles-in the field cricket Teleogryllus oceanicus and tested whether population genetic divergence predicts the extent or direction of social flexibility in allopatric populations. We manipulated male crickets' social environments during rearing and then characterized CHC profiles. CHC signatures varied considerably across populations and also in response to the social environment, but our prediction that increased social flexibility would be selected in more recently founded populations exposed to fluctuating demographic environments was unsupported. Furthermore, models examining the influence of drift and selection failed to support a role of sexual selection in driving population divergence in CHC profiles. Variation in social environments might alter the dynamics of sexual selection, but our results align with theoretical predictions that the role social flexibility plays in modulating evolutionary divergence depends critically on whether responses to variation in the social environment are homogeneous across populations, or whether gene by social environment interactions occur.

  12. Species Detection and Identification in Sexual Organisms Using Population Genetic Theory and DNA Sequences

    PubMed Central

    Birky, C. William

    2013-01-01

    Phylogenetic trees of DNA sequences of a group of specimens may include clades of two kinds: those produced by stochastic processes (random genetic drift) within a species, and clades that represent different species. The ratio of the mean pairwise sequence difference between a pair of clades (K) to the mean pairwise sequence difference within a clade (θ) can be used to determine whether the clades are samples from different species (K/θ≥4) or the same species (K/θ<4) with probability ≥0.95. Previously I applied this criterion to delimit species of asexual organisms. Here I use data from the literature to show how it can also be applied to delimit sexual species using four groups of sexual organisms as examples: ravens, spotted leopards, sea butterflies, and liverworts. Mitochondrial or chloroplast genes are used because these segregate earlier during speciation than most nuclear genes and hence detect earlier stages of speciation. In several cases the K/θ ratio was greater than 4, confirming the original authors' intuition that the clades were sufficiently different to be assigned to different species. But the K/θ ratio split each of two liverwort species into two evolutionary species, and showed that support for the distinction between the common and Chihuahuan raven species is weak. I also discuss some possible sources of error in using the K/θ ratio; the most significant one would be cases where males migrate between different populations but females do not, making the use of maternally inherited organelle genes problematic. The K/θ ratio must be used with some caution, like all other methods for species delimitation. Nevertheless, it is a simple theory-based quantitative method for using DNA sequences to make rigorous decisions about species delimitation in sexual as well as asexual eukaryotes. PMID:23308113

  13. International Conference on Population and Development at 15 Years: Achieving Sexual and Reproductive Health and Rights for All?

    PubMed Central

    Roseman, Mindy Jane

    2010-01-01

    Sexual and reproductive health remains the contentious concept it was at the 1994 United Nations International Conference on Population and Development (ICPD), held in Cairo, Egypt. In light of the recent 15-year review of ICPD, we suggest several areas where advocates, practitioners, and researchers can inform future progress for sexual and reproductive health. These include the following: improving measurement and accountability related to the evidence base for sexual and reproductive health, indicators of program success, and the tracking of resource flows; creating and renewing alliances to strengthen advocacy; and employing new resource mobilization strategies. Given the 20-year goals established at ICPD, now is the time to move toward finally achieving the sexual and reproductive health and rights agenda. PMID:20075310

  14. Can sexual selection theory inform genetic management of captive populations? A review

    PubMed Central

    Chargé, Rémi; Teplitsky, Céline; Sorci, Gabriele; Low, Matthew

    2014-01-01

    Captive breeding for conservation purposes presents a serious practical challenge because several conflicting genetic processes (i.e., inbreeding depression, random genetic drift and genetic adaptation to captivity) need to be managed in concert to maximize captive population persistence and reintroduction success probability. Because current genetic management is often only partly successful in achieving these goals, it has been suggested that management insights may be found in sexual selection theory (in particular, female mate choice). We review the theoretical and empirical literature and consider how female mate choice might influence captive breeding in the context of current genetic guidelines for different sexual selection theories (i.e., direct benefits, good genes, compatible genes, sexy sons). We show that while mate choice shows promise as a tool in captive breeding under certain conditions, for most species, there is currently too little theoretical and empirical evidence to provide any clear guidelines that would guarantee positive fitness outcomes and avoid conflicts with other genetic goals. The application of female mate choice to captive breeding is in its infancy and requires a goal-oriented framework based on the needs of captive species management, so researchers can make honest assessments of the costs and benefits of such an approach, using simulations, model species and captive animal data. PMID:25553072

  15. Large scale structure of the globular cluster population in Coma

    NASA Astrophysics Data System (ADS)

    Gagliano, Alexander T.; O'Neill, Conor; Madrid, Juan P.

    2016-01-01

    A search for globular cluster candidates in the Coma Cluster was carried out using Hubble Space Telescope data taken with the Advanced Camera for Surveys. We combine different observing programs including the Coma Treasury Survey in order to obtain the large scale distribution of globular clusters in Coma. Globular cluster candidates were selected through careful morphological inspection and a detailed analysis of their magnitude and colors in the two available wavebands, F475W (Sloan g) and F814W (I). Color Magnitude Diagrams, radial density plots and density maps were then created to characterize the globular cluster population in Coma. Preliminary results show the structure of the intergalactic globular cluster system throughout Coma, among the largest globular clusters catalogues to date. The spatial distribution of globular clusters shows clear overdensities, or bridges, between Coma galaxies. It also becomes evident that galaxies of similar luminosity have vastly different numbers of associated globular clusters.

  16. Prevalence of sexual problems in Portugal: results of a population-based study using a stratified sample of men aged 18 to 70 years.

    PubMed

    Quinta Gomes, Ana Luísa; Nobre, Pedro J

    2014-01-01

    Despite the use of different methodologies, target populations, and clinical definitions of sexual problems, recent epidemiological studies have shown that the occurrence of sexual difficulties is a very common experience among men from the general population regardless of their age. The objective of this study was to present epidemiological data on the prevalence of sexual difficulties in a community sample of 650 sexually active Portuguese men, stratified by age, marital status, and educational level. Participants completed a self-reported questionnaire assessing sexual function in the previous four weeks (International Index of Erectile Function). Results showed that sexual difficulties were relatively common among this sample. Rapid ejaculation was the most frequently reported sexual difficulty (23.2%), followed by erectile difficulties (10.2%), orgasm problems (8.2%), and low desire (2.9%) in the previous four weeks. With the exception of rapid ejaculation, all categories showed age-specific prevalence rates, with sexual difficulties increasing gradually in men above age 45. Age was a significant predictor of all sexual difficulties except rapid ejaculation, and lower educational levels were related to orgasm difficulties. Findings are consistent with the majority of epidemiological studies indicating a high prevalence of sexual difficulties among men in the general population and highlight the importance and the need to implement sexual health promotion programs in the target population.

  17. Self-reported psychopathic traits in sexually offending juveniles compared with generally offending juveniles and general population youth.

    PubMed

    Boonmann, Cyril; Jansen, Lucres M C; 't Hart-Kerkhoffs, Lisette A; Vahl, Pauline; Hillege, Sanne L; Doreleijers, Theo A H; Vermeiren, Robert R J M

    2015-01-01

    The aim of the current study is to gain a better insight into the relationship between sexually aggressive behaviour and psychopathy in youths; juveniles who sexually offended (JSOs) were compared with generally offending youths and a general population group. Seventy-one JSOs, 416 detained general offenders, and 331 males from the general population were assessed by means of the Youth Psychopathic traits Inventory (YPI), a self-report instrument. Sexually and generally offending juveniles had significantly lower levels of self-reported psychopathic traits than youths from the general population. Juvenile sexual offenders and generally offending juveniles did not differ in self-reported psychopathic traits. Furthermore, no differences in self-reported psychopathic traits were found between subgroups of JSOs (i.e., child molesters, solo offenders, and group offenders). The finding that self-reported psychopathic traits are less prevalent in offending juveniles than in general population youths raises questions about the usefulness of the YPI when comparing psychopathic traits between clinical samples and general-population samples.

  18. The Relation Between Compulsive Sexual Behaviors and Aggression in a Substance-Dependent Population

    PubMed Central

    Elmquist, JoAnna; Shorey, Ryan C.; Anderson, Scott; Stuart, Gregory L.

    2016-01-01

    Research supports a high comorbidity between compulsive sexual behaviors (CSBs) and SUDs, which are both classified by increased impulsivity. Literature has also indicated that increased impulsivity and substance use are associated with aggression. However, no known research has examined the relationship between CSBs and aggression among a substance dependent population. The purpose of the current study was to examine this relationship. Participants included 349 male patients in treatment for SUDs. Results indicated that after controlling for alcohol and drug use and problems and age, CSBs were significantly associated with total aggression, aggressive attitudes, physical aggression, and verbal aggression. This is the first known study to examine this relationship, thus continued research is needed to extend and replicate these findings. PMID:27445453

  19. Advances in Substance Abuse Prevention and Treatment Interventions Among Racial, Ethnic, and Sexual Minority Populations.

    PubMed

    Bloom, Arthur W

    2016-01-01

    Substance abuse research among racial, ethnic, and sexual minority populations historically has lagged behind that conducted with majority samples. However, interesting and potentially important advances in prevention, brief interventions, and treatment have been made in the last few years, at least among some minority populations, such as American Indian youth. New prevention efforts have focused on point-of-sale interventions for alcohol, as well as on family-unit interventions designed with subpopulation cultural values in mind. In addition, previously established evidence-based and culturally relevant interventions are being combined with computer technology. Empirical data support using brief interventions with patients of color in medical settings, capitalizing on teachable and reachable moments during a physical trauma or other health crisis. Finally, use of empirically supported treatment may be helpful, with a caveat that these interventions must appropriately match cultural traditions and respect the values of the clients. More research clearly is needed, especially among certain minority populations in the United States. A greater emphasis should be placed on developing novel, culturally grounded interventions in partnership with communities, in addition to adapting existing mainstream interventions for use by other cultures.

  20. Advances in Substance Abuse Prevention and Treatment Interventions Among Racial, Ethnic, and Sexual Minority Populations

    PubMed Central

    Blume, Arthur W.

    2016-01-01

    Substance abuse research among racial, ethnic, and sexual minority populations historically has lagged behind that conducted with majority samples. However, interesting and potentially important advances in prevention, brief interventions, and treatment have been made in the last few years, at least among some minority populations, such as American Indian youth. New prevention efforts have focused on point-of-sale interventions for alcohol, as well as on family-unit interventions designed with subpopulation cultural values in mind. In addition, previously established evidence-based and culturally relevant interventions are being combined with computer technology. Empirical data support using brief interventions with patients of color in medical settings, capitalizing on teachable and reachable moments during a physical trauma or other health crisis. Finally, use of empirically supported treatment may be helpful, with a caveat that these interventions must appropriately match cultural traditions and respect the values of the clients. More research clearly is needed, especially among certain minority populations in the United States. A greater emphasis should be placed on developing novel, culturally grounded interventions in partnership with communities, in addition to adapting existing mainstream interventions for use by other cultures. PMID:27159811

  1. Use of the Internet for Sexual Health Among Sexually Experienced Persons Aged 16 to 44 Years: Evidence from a Nationally Representative Survey of the British Population

    PubMed Central

    Estcourt, Claudia S; Johnson, Anne M; Sonnenberg, Pam; Wellings, Kaye; Mercer, Catherine H

    2016-01-01

    Background Those who go online regarding their sexual health are potential users of new Internet-based sexual health interventions. Understanding the size and characteristics of this population is important in informing intervention design and delivery. Objective We aimed to estimate the prevalence in Britain of recent use of the Internet for key sexual health reasons (for chlamydia testing, human immunodeficiency virus [HIV] testing, sexually transmitted infection [STI] treatment, condoms/contraceptives, and help/advice with one’s sex life) and to identify associated sociodemographic and behavioral factors. Methods Complex survey analysis of data from 8926 sexually experienced persons aged 16-44 years in a 2010-2012 probability survey of Britain’s resident population. Prevalence of recent (past year) use of Internet sources for key sexual health reasons was estimated. Factors associated with use of information/support websites were identified using logistic regression to calculate age-adjusted odds ratios (AORs). Results Recent Internet use for chlamydia/HIV testing or STI treatment (combined) was very low (men: 0.31%; women: 0.16%), whereas 2.35% of men and 0.51% of women reported obtaining condoms/contraceptives online. Additionally, 4.49% of men and 4.57% of women reported recent use of information/support websites for advice/help with their sex lives. Prevalence declined with age (men 16-24 years: 7.7%; 35-44 years: 1.84%, P<.001; women 16-24 years: 7.8%; 35-44 years: 1.84%, P<.001). Use of information/support websites was strongly associated with men’s higher socioeconomic status (managerial/professional vs semiroutine/routine: AOR 1.93, 95% CI 1.27-2.93, P<.001). Despite no overall association with area-level deprivation, those in densely populated urban areas were more likely to report use of information/support websites than those living in rural areas (men: AOR 3.38, 95% CI 1.68-6.77, P<.001; women: AOR 2.51, 95% CI 1.34-4.70, P<.001). No

  2. Genetic variation in male sexual behaviour in a population of white-footed mice in relation to photoperiod

    PubMed Central

    Sharp, Kathy; Bucci, Donna; Zelensky, Paul K.; Chesney, Alanna; Tidhar, Wendy; Broussard, David R.; Heideman, Paul D.

    2015-01-01

    In natural populations, genetic variation in seasonal male sexual behaviour could affect behavioural ecology and evolution. In a wild-source population of white-footed mice, Peromyscus leucopus, from Virginia, U.S.A., males experiencing short photoperiod show high levels of genetic variation in reproductive organ mass and neuroendocrine traits related to fertility. We tested whether males from two divergent selection lines, one that strongly suppresses fertility under short photoperiod (responder) and one that weakly suppresses fertility under short photoperiod (nonresponder), also differ in photoperiod-dependent sexual behaviour and responses to female olfactory cues. Under short, but not long, photoperiod, there were significant differences between responder and nonresponder males in sexual behaviour and likelihood of inseminating a female. Males that were severely oligospermic or azoospermic under short photoperiod failed to display sexual behaviour in response to an ovariectomized and hormonally primed receptive female. However, on the day following testing, females were positive for spermatozoa only when paired with a male having a sperm count in the normal range for males under long photoperiod. Males from the nonresponder line showed accelerated reproductive development under short photoperiod in response to urine-soiled bedding from females, but males from the responder line did not. The results indicate genetic variation in sexual behaviour that is expressed under short, but not long, photoperiod, and indicate a potential link between heritable neuroendocrine variation and male sexual behaviour. In winter in a natural population, this heritable behavioural variation could affect fitness, seasonal life history trade-offs and population growth. PMID:25983335

  3. The power to detect quantitative trait loci using resequenced, experimentally evolved populations of diploid, sexual organisms.

    PubMed

    Baldwin-Brown, James G; Long, Anthony D; Thornton, Kevin R

    2014-04-01

    A novel approach for dissecting complex traits is to experimentally evolve laboratory populations under a controlled environment shift, resequence the resulting populations, and identify single nucleotide polymorphisms (SNPs) and/or genomic regions highly diverged in allele frequency. To better understand the power and localization ability of such an evolve and resequence (E&R) approach, we carried out forward-in-time population genetics simulations of 1 Mb genomic regions under a large combination of experimental conditions, then attempted to detect significantly diverged SNPs. Our analysis indicates that the ability to detect differentiation between populations is primarily affected by selection coefficient, population size, number of replicate populations, and number of founding haplotypes. We estimate that E&R studies can detect and localize causative sites with 80% success or greater when the number of founder haplotypes is over 500, experimental populations are replicated at least 25-fold, population size is at least 1,000 diploid individuals, and the selection coefficient on the locus of interest is at least 0.1. More achievable experimental designs (less replicated, fewer founder haplotypes, smaller effective population size, and smaller selection coefficients) can have power of greater than 50% to identify a handful of SNPs of which one is likely causative. Similarly, in cases where s ≥ 0.2, less demanding experimental designs can yield high power.

  4. The Sexual Risk Context among the FEM-PrEP Study Population in Bondo, Kenya and Pretoria, South Africa

    PubMed Central

    Headley, Jennifer; Lemons, Ansley; Corneli, Amy; Agot, Kawango; Ahmed, Khatija; Wang, Meng; Odhiambo, Jacob; Skhosana, Joseph; Tharaldson, Jenae; Van Damme, Lut; MacQueen, Kathleen

    2014-01-01

    Background Incidence rates in the FEM-PrEP and VOICE trials demonstrate that women from diverse sub-Saharan African communities continue to be at substantial HIV risk. Objective To describe and compare the sexual risk context of the study population from two FEM-PrEP trial sites–Bondo, Kenya, and Pretoria, South Africa. Methods At baseline we collected information about demographics, sexual behaviors, and partnership beliefs through quantitative questionnaires with all participants (Bondo, n = 720; Pretoria, n = 750). To explore the sexual risk context, we also conducted qualitative, semi-structured interviews with HIV-negative participants randomly selected at several time points (Bondo, n = 111; Pretoria, n = 69). Results Demographics, sexual behavior, and partnership beliefs varied significantly between the sites. Bondo participants were generally older, had fewer years of schooling, and were more likely to be employed and married compared to Pretoria participants. Bondo participants were more likely to report multiple partners and not knowing whether their partner had HIV than Pretoria participants. A significantly higher percentage of Bondo participants reported engaging in sex without a condom with their primary and other partners compared to Pretoria participants. We found a borderline association between participants who reported not using condoms in the 4 weeks prior to baseline and lower risk of HIV infection, and no association between having more than one sexual partner at baseline and HIV infection. Discussion Despite significantly different demographics, sexual behaviors, and partnership beliefs, many women in the FEM-PrEP trial were at risk of acquiring HIV as demonstrated by the sites’ high HIV incidence. Though gender dynamics differed between the populations, they appear to play a critical role in women’s sexual practices. The findings highlight different ways women from diverse contexts may be at-risk for HIV and the

  5. Sexual Abuse and Suicidality: Gender Differences in a Large Community Sample of Adolescents

    ERIC Educational Resources Information Center

    Martin, Graham; Bergen, Helen A.; Richardson, Angela S.; Roeger, Leigh; Allison, Stephen

    2004-01-01

    Objective: A cross-sectional study of gender specific relationships between self-reported child sexual abuse and suicidality in a community sample of adolescents. Method: Students aged 14 years on average (N=2,485) from 27 schools in South Australia completed a questionnaire including items on sexual abuse and suicidality, and measures of…

  6. Psychopathology in a Large Cohort of Sexually Abused Children Followed up to 43 Years

    ERIC Educational Resources Information Center

    Cutajar, Margaret C.; Mullen, Paul E.; Ogloff, James R. P.; Thomas, Stuart D.; Wells, David L.; Spataro, Josie

    2010-01-01

    Objective: To determine the rate and risk of clinical and personality disorders diagnosed in childhood and adulthood in those known to have been sexually abused during childhood. Methods: Forensic medical records of 2,759 sexually abused children assessed between 1964 and 1995 were linked with a public psychiatric database between 12 and 43 years…

  7. Prevalence of sexually transmitted pathogens associated with HPV infection in cervical samples in a Mexican population.

    PubMed

    Magaña-Contreras, Mariana; Contreras-Paredes, Adriana; Chavez-Blanco, Alma; Lizano, Marcela; De la Cruz-Hernandez, Yanira; De la Cruz-Hernandez, Erick

    2015-12-01

    Cervical cancer development has been mainly associated with persistent human papillomavirus (HPV) infections. However, HPV infection is unlikely to be sufficient to cause cervical cancer, and the contribution of other sexually transmitted infections (STIs) could be the determining factor for cervical lesion-progression. The aim of this study was to estimate the prevalence of STIs associated with HPV-positivity in 201 cervical samples from patients who underwent annual routine gynecological exams. The overall prevalence of STIs was 57.7%, and the most frequent infection was Ureaplasma spp (UP) (39.8%), followed by Gardnerella vaginalis (GV) (25.9%), α-HPV (18.4%), Chlamydia trachomatis (CT) (1.5%), and Mycoplasma genitalium (MG) (0.5%). The highest prevalence rate of multiple non-HPV infections was observed for the age-range 31-40; for papillomavirus infection, the age-range was 21-30. In normal cervical samples, HPV16 was the most prevalent genotype (24.3%), followed by genotypes 58 (13.5%) and 52 (10.8%). Intriguingly, HPV18 was not detected in the study population, and genotypes 52 and 58 were found exclusively in samples with abnormal cytology. Papillomavirus infection with oncogenic types was significantly associated with GV (P = 0.025) and strongly associated with multiple non-HPV pathogens (P = 0.002). The following variables correlated significantly with cytological diagnosis of low-grade squamous intraepithelial lesion (LSIL): GV (P = 0.028), multiple non-HPV infections (P = 0.001), and high-risk HPV positivity (P = 0.001). Epidemiological data from this study will contribute to the molecular detection of sexually transmitted pathogens from screening programs to identify those women who are at risk for developing cervical lesions.

  8. Cryptic sexual populations account for genetic diversity and ecological success in a widely distributed, asexual fungus-growing ant

    PubMed Central

    Rabeling, Christian; Gonzales, Omar; Schultz, Ted R.; Bacci, Maurício; Garcia, Marcos V. B.; Verhaagh, Manfred; Ishak, Heather D.; Mueller, Ulrich G.

    2011-01-01

    Sex and recombination are central processes in life generating genetic diversity. Organisms that rely on asexual propagation risk extinction due to the loss of genetic diversity and the inability to adapt to changing environmental conditions. The fungus-growing ant species Mycocepurus smithii was thought to be obligately asexual because only parthenogenetic populations have been collected from widely separated geographic localities. Nonetheless, M. smithii is ecologically successful, with the most extensive distribution and the highest population densities of any fungus-growing ant. Here we report that M. smithii actually consists of a mosaic of asexual and sexual populations that are nonrandomly distributed geographically. The sexual populations cluster along the Rio Amazonas and the Rio Negro and appear to be the source of independently evolved and widely distributed asexual lineages, or clones. Either apomixis or automixis with central fusion and low recombination rates is inferred to be the cytogenetic mechanism underlying parthenogenesis in M. smithii. Males appear to be entirely absent from asexual populations, but their existence in sexual populations is indicated by the presence of sperm in the reproductive tracts of queens. A phylogenetic analysis of the genus suggests that M. smithii is monophyletic, rendering a hybrid origin of asexuality unlikely. Instead, a mitochondrial phylogeny of sexual and asexual populations suggests multiple independent origins of asexual reproduction, and a divergence-dating analysis indicates that M. smithii evolved 0.5–1.65 million years ago. Understanding the evolutionary origin and maintenance of asexual reproduction in this species contributes to a general understanding of the adaptive significance of sex. PMID:21768368

  9. Cryptic sexual populations account for genetic diversity and ecological success in a widely distributed, asexual fungus-growing ant.

    PubMed

    Rabeling, Christian; Gonzales, Omar; Schultz, Ted R; Bacci, Maurício; Garcia, Marcos V B; Verhaagh, Manfred; Ishak, Heather D; Mueller, Ulrich G

    2011-07-26

    Sex and recombination are central processes in life generating genetic diversity. Organisms that rely on asexual propagation risk extinction due to the loss of genetic diversity and the inability to adapt to changing environmental conditions. The fungus-growing ant species Mycocepurus smithii was thought to be obligately asexual because only parthenogenetic populations have been collected from widely separated geographic localities. Nonetheless, M. smithii is ecologically successful, with the most extensive distribution and the highest population densities of any fungus-growing ant. Here we report that M. smithii actually consists of a mosaic of asexual and sexual populations that are nonrandomly distributed geographically. The sexual populations cluster along the Rio Amazonas and the Rio Negro and appear to be the source of independently evolved and widely distributed asexual lineages, or clones. Either apomixis or automixis with central fusion and low recombination rates is inferred to be the cytogenetic mechanism underlying parthenogenesis in M. smithii. Males appear to be entirely absent from asexual populations, but their existence in sexual populations is indicated by the presence of sperm in the reproductive tracts of queens. A phylogenetic analysis of the genus suggests that M. smithii is monophyletic, rendering a hybrid origin of asexuality unlikely. Instead, a mitochondrial phylogeny of sexual and asexual populations suggests multiple independent origins of asexual reproduction, and a divergence-dating analysis indicates that M. smithii evolved 0.5-1.65 million years ago. Understanding the evolutionary origin and maintenance of asexual reproduction in this species contributes to a general understanding of the adaptive significance of sex.

  10. How large was the founding population of Darwin's finches?

    PubMed Central

    Vincek, V.; O'Huigin, C.; Satta, Y.; Takahata, Y.; Boag, P. T.; Grant, P. R.; Grant, B. R.; Klein, J.

    1997-01-01

    A key assumption of many allopatric speciation models is that evolution in peripheral or isolated populations is facilitated by drastic reductions in population size. Population bottlenecks are believed to lead to rapid changes in gene frequencies through genetic drift, to facilitate rapid emergence of novel phenotypes, and to enhance reproductive isolation via genetic revolutions. For such effects to occur, founding populations must be very small, and remain small for some time after founding. This assumption has, however, rarely been tested in nature. One approach is to exploit the polymorphism of the major histocompatibility complex (Mhc) to obtain information about the founding population. Here, we use the Mhc polymorphism to estimate the size of the founding population of Darwin's finches in the Galápagos Archipelago. The results indicate that the population could not have been smaller than 30 individuals.

  11. Seroprevalence and incidence of sexually transmitted diseases in a rural Ugandan population.

    PubMed

    Wagner, H U; Van Dyck, E; Roggen, E; Nunn, A J; Kamali, A; Schmid, D S; Dobbins, J G; Mulder, D W

    1994-01-01

    The aim of the study was to determine in a rural population the age- and sex-specific prevalence and incidence rates of serological reactivity of 5 common sexually transmitted diseases (STDs) and their association with HIV-1 antibody status. Of the adult population of two villages (529 adults aged 15 years or more) 294 provided an adequate blood specimen both on enrollment and at 12 months. The sera were tested at 3 collaborating laboratories for antibodies against HIV-1, Treponema pallidum, Haemophilus ducreyi, Chlamydia trachomatis and herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2). A sample of 45 children were tested for HSV-1 and HSV-2. Seroprevalence rates in adults on enrollment were 7.8% for HIV-1, 10.8% for active syphilis, 10.4% for H. ducreyi, 66.0% for C. trachomatis, 91.2% for HSV-1 and 67.9% for HSV-2. Males were significantly more likely than females to be seropositive for H. ducreyi (15.6% versus 6.6%), but less likely to be HSV-2 antibody positive (57.0% versus 74.4%). Reactivity to H. ducreyi, C. trachomatis and HSV-2 rose with increasing age. In contrast, active syphilis showed no age trend. All STDs tended to be more common in those HIV-1 seropositive. Incidence rates over the 12 months were nil for HIV-1, 0.5% for syphilis, 1.2% for H. ducreyi, 11.3% for C. trachomatis, and 16.7% for HSV-2. The results of this exploratory study indicate that all STDs included are common in this rural population. The high HSV-2 prevalence rate among adolescents suggests that HSV-2 may be an important risk factor for HIV-1 infection.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Getting the timing right: antler growth phenology and sexual selection in a wild red deer population.

    PubMed

    Clements, Michelle N; Clutton-Brock, Tim H; Albon, Steve D; Pemberton, Josephine M; Kruuk, Loeske E B

    2010-10-01

    There has been growing interest in the determinants of the annual timing of biological phenomena, or phenology, in wild populations, but research on vertebrate taxa has primarily focused on the phenology of reproduction. We present here analyses of the phenology of the annual growth of a secondary sexual characteristic, antlers in red deer (Cervus elaphus) males. The long-term individual-based data from a wild population of red deer on the Isle of Rum, Scotland allow us to consider ecological factors influencing variation in the phenology of growth of antlers, and the implications of variation in antler growth phenology with respect to the phenotype of antler grown (antler mass) and annual breeding success. The phenology of antler growth was influenced by local environmental conditions: higher population density delayed both the start date (during spring) and the relative end date (in late summer) of antler growth, and warmer temperatures in the September and April prior to growth advanced start and end dates, respectively. Furthermore, there was variation between individuals in this phenotypic plasticity of start date, although not in that of end date of growth. The phenology of antler growth impacted on the morphology of antlers grown, with individuals who started and ended growth earliest having the heaviest antlers. The timing of antler growth phenology was associated with breeding success in the following mating season, independently of the mass of antlers grown: an earlier start of antler growth was associated with siring a higher number of the calves born the following spring. Our results suggest that the phenology of traits that are not directly correlated with offspring survival may also regularly show correlations with fitness.

  13. Engaging a state: Facebook comments on a large population biobank.

    PubMed

    Platt, Tevah; Platt, Jodyn; Thiel, Daniel; Kardia, Sharon L R

    2017-04-05

    Scholarship on newborn screening, dried bloodspot retention, and large population biobanking call consistently for improved public engagement. Communication with participants likely occurs only in the context of collection, consent, or notification, if at all. We ran an 11-week advertising campaign to inform Michigan Facebook users unlikely to know that their or their children's dried bloodspots (DBSs) were stored in a state biobank. We investigated the pattern and content of comments posted during the campaign, focusing on users' questions, attitudes and concerns, and the role the moderator played in addressing them. We used Facebook data to quantitatively assess engagement and employed conventional content analysis to investigate themes, attitudes, and social dynamics among user and moderator comments. Five ad sets elicited comments during campaign weeks 4-8, reaching ∼800,000 Facebook users ($6000). Gravitating around broad, underlying ethical, legal, and social issues, 180 posts from 129 unique users related to newborn screening or biobanking. Thirty six conveyed negative attitudes and 33 conveyed positive attitudes; 53 posed questions. The most prevalent themes identified were consent, privacy, bloodspot use, identifiability, inclusion criteria, research benefits, (mis)trust, genetics, DBS destruction, awareness, and the role of government. The moderator's 81 posts were responsive-answering questions, correcting or clarifying information, or providing information about opting out. Facebook ad campaigns can improve engagement by pushing out relevant content and creating dynamic, responsive, visible forums for discussion. Reduced control over messaging may be worth the trade-off for creating accessible, transparent, people-centered engagement on public health issues that are sensitive and complex.

  14. Antarctic krill population genomics: apparent panmixia, but genome complexity and large population size muddy the water.

    PubMed

    Deagle, Bruce E; Faux, Cassandra; Kawaguchi, So; Meyer, Bettina; Jarman, Simon N

    2015-10-01

    Antarctic krill (Euphausia superba; hereafter krill) are an incredibly abundant pelagic crustacean which has a wide, but patchy, distribution in the Southern Ocean. Several studies have examined the potential for population genetic structuring in krill, but DNA-based analyses have focused on a limited number of markers and have covered only part of their circum-Antarctic range. We used mitochondrial DNA and restriction site-associated DNA sequencing (RAD-seq) to investigate genetic differences between krill from five sites, including two from East Antarctica. Our mtDNA results show no discernible genetic structuring between sites separated by thousands of kilometres, which is consistent with previous studies. Using standard RAD-seq methodology, we obtained over a billion sequences from >140 krill, and thousands of variable nucleotides were identified at hundreds of loci. However, downstream analysis found that markers with sufficient coverage were primarily from multicopy genomic regions. Careful examination of these data highlights the complexity of the RAD-seq approach in organisms with very large genomes. To characterize the multicopy markers, we recorded sequence counts from variable nucleotide sites rather than the derived genotypes; we also examined a small number of manually curated genotypes. Although these analyses effectively fingerprinted individuals, and uncovered a minor laboratory batch effect, no population structuring was observed. Overall, our results are consistent with panmixia of krill throughout their distribution. This result may indicate ongoing gene flow. However, krill's enormous population size creates substantial panmictic inertia, so genetic differentiation may not occur on an ecologically relevant timescale even if demographically separate populations exist.

  15. Prevalence and sociodemographic predictors of sexual problems in Portugal: a population-based study with women aged 18 to 79 years.

    PubMed

    Peixoto, Maria Manuela; Nobre, Pedro

    2015-01-01

    Studies on epidemiology of female sexual problems consistently indicate high prevalence rates worldwide, suggesting that this clinical presentation should be considered as a public health concern. However, there are no published studies on prevalence of sexual problems in Portugal. The present study investigated the prevalence, severity, and comorbidity of female sexual problems in a Portuguese community sample. In addition, the authors assessed the role of sociodemographic predictors of women's sexual difficulties. The authors recruited 500 women using quota methods to resemble the Portuguese population according to its demographic characteristics. Participants answered to the Female Sexual Function Index and to a sociodemographic questionnaire. Findings indicated that 37.9% of the Portuguese women reported symptoms of sexual problems. Symptoms of lack of sexual desire was the most frequent sexual difficulty with 25.4% of the women reporting low desire most times or always, followed by symptoms of orgasmic (16.8%), sexual arousal (15.1%), and lubrication difficulties (12.9%), dyspareunia (9.8%), and vaginismus (6.6%). Results indicated that age was a significant predictor of female sexual problems. Results also indicated that symptoms of female sexual problems are a significant health concern in Portugal, suggesting that public policies should be developed to promote sexual health.

  16. The Relationship between Mating System and Genetic Diversity in Diploid Sexual Populations of Cyrtomium falcatum in Japan

    PubMed Central

    Matsumoto, Sadamu; Ebihara, Atsushi; Watano, Yasuyuki

    2016-01-01

    The impact of variation in mating system on genetic diversity is a well-debated topic in evolutionary biology. The diploid sexual race of Cyrtomium falcatum (Japanese holly fern) shows mating system variation, i.e., it displays two different types of sexual expression (gametangia formation) in gametophytes: mixed (M) type and separate (S) type. We examined whether there is variation in the selfing rate among populations of this species, and evaluated the relationship between mating system, genetic diversity and effective population size using microsatellites. In this study, we developed eight new microsatellite markers and evaluated genetic diversity and structure of seven populations (four M-type and three S-type). Past effective population sizes (Ne) were inferred using Approximate Bayesian computation (ABC). The values of fixation index (FIS), allelic richness (AR) and gene diversity (h) differed significantly between the M-type (FIS: 0.626, AR: 1.999, h: 0.152) and the S-type (FIS: 0.208, AR: 2.718, h: 0.367) populations (when admixed individuals were removed from two populations). Although evidence of past bottleneck events was detected in all populations by ABC, the current Ne of the M-type populations was about a third of that of the S-type populations. These results suggest that the M-type populations have experienced more frequent bottlenecks, which could be related to their higher colonization ability via gametophytic selfing. Although high population differentiation among populations was detected (FST = 0.581, F’ST = 0.739), there was no clear genetic differentiation between the M- and S-types. Instead, significant isolation by distance was detected among all populations. These results suggest that mating system variation in this species is generated by the selection for single spore colonization during local extinction and recolonization events and there is no genetic structure due to mating system. PMID:27706257

  17. Sexual and reproductive knowledge, attitudes and behaviours in a school going population of Sri Lankan adolescents.

    PubMed

    Rajapaksa-Hewageegana, Neelamani; Piercy, Hilary; Salway, Sarah; Samarage, Sarath

    2015-03-01

    The reproductive and sexual health of adolescents is an important health concern and a focus of global attention. In Sri Lanka, a lack of understanding about adolescent reproductive and sexual health needs is a matter of national concern. A survey was undertaken to examine the sexual knowledge, attitudes and behaviours of school going adolescents in Sri Lanka. A random sample of schools was selected from one district. Data were collected by a self-completion questionnaire and analysed using SPSS. Response rate was 90%. 2020 pupils (26% boys, 74% girls) aged 16-19 years (mean=16.9) participated, the majority Sinhalese (97%). Most reported a good parent-child relationship (88%). A minority (34%) discussed sexual issues with parents. Health professionals were the preferred source of sexual information (32%) rather than parents (12.5%) or friends (5.6%). Less than 1% demonstrated satisfactory sexual and reproductive knowledge levels. 1.7% were sexually active (30 boys vs 5 girls), the majority with same age partners. 57% used contraception at first intercourse. There is an imperative to address the lack of sexual and reproductive knowledge. A minority of school going adolescents become sexually active. These individuals are potentially vulnerable and services need to be developed to meet their needs.

  18. Large variation in mitochondrial DNA of sexual and parthenogenetic Dahlica triquetrella (Lepidoptera: Psychidae) shows multiple origins of parthenogenesis

    PubMed Central

    2013-01-01

    Background Obligate parthenogenesis is relatively rare in animals. Still, in some groups it is quite common and has evolved and persisted multiple times. These groups may provide important clues to help solve the ‘paradox of sex’. Several species in the Psychidae (Lepidoptera) have obligate parthenogenesis. Dahlica triquetrella is one of those species where multiple transitions to parthenogenesis are postulated based on intensive cytological and behavioural studies. This has led to the hypothesis that multiple transitions from sexuals to diploid parthenogens occurred during and after the last glacial period, followed by transitions from parthenogenetic diploids to parthenogenetic tetraploids. Our study is the first to test these hypotheses using a molecular phylogeny based on mtDNA from multiple sexual and parthenogenetic populations from a wide geographic range. Results Parthenogenetic (and sexual) D. triquetrella are not monophyletic, and considerable sequence variation is present suggesting multiple transitions to parthenogenesis. However, we could not establish ancestral sexual haplotypes from our dataset. Our data suggest that some parthenogenetic clades have evolved, indicating origins of parthenogenesis before the last glacial period. Conclusions Multiple transitions to parthenogenesis have taken place in Dahlica triquetrella, confirming previous hypotheses. The number of different parthenogenetic clades, haplotypes and their apparent evolutionary age, clearly show that parthenogenesis has been a very successful reproductive strategy in this species over a long period. PMID:23622052

  19. Sexually transmitted infections treatment and care available to high risk populations in Pakistan.

    PubMed

    Rahimtoola, Minal; Hussain, Hamidah; Khowaja, Saira N; Khan, Aamir J

    2008-01-01

    Limited literature exists on the quality and availability of treatment and care of sexually transmitted infections (STIs) in Pakistan. This article aims to document existing services for the care and treatment of STIs available in Pakistan's public and private sectors to high risk groups (HRG), particularly the transgendered population. We conducted a cross-sectional survey to document STI services in Lahore, Karachi, Rawalpindi, Peshawar, and Quetta. Seventy-three interviews were administered with health service providers at the 3 largest public sector hospitals in each city, as well as with general physicians and traditional healers in the private sector. Twenty-five nongovernmental organizations (NGO) providing STI services were also interviewed. Fewer than 45% of private and public sector general practitioners had been trained in STI treatment after the completion of their medical curriculum, and none of the traditional healers had received any formal training or information on STIs. The World Health Organization (WHO) syndromic management guidelines were followed for STI management by 29% of public and private sector doctors and 5% of traditional healers. STI drugs were available at no cost at 44% of NGOs and at some public sector hospitals. Our findings show that although providers do treat HRGs for STIs, there are significant limitations in their ability to provide these services. These deterrents include, but are not limited to, a lack of STI training of service providers, privacy and adherence to recommended WHO syndromic management guidelines, and costly diagnostic and consultation fees.

  20. Sexual dimorphism in foramen magnum dimensions in the South Indian population: A digital submentovertex radiographic study

    PubMed Central

    Raikar, Neha Ajit; Meundi, Manasa A; David, Chaya M; Rao, Mahesh Dathu; Jogigowda, Sanjay Chikkarasinakere

    2016-01-01

    Purpose of the Study: Personal identification is a vital arena of forensic investigation, facilitating the search for missing persons. This process of identification is eased by the determination of age, sex, and ethnicity. In situations where there are fragmented and mutilated skeletal remains, sex determination is relatively difficult, and it becomes important to establish the accuracy of individual bones. Aim: This study aims to evaluate sexual dimorphism in foramen magnum (FM) dimensions in the South Indian population using digital submentovertex (SMV) radiograph. Materials and Methods: 150 individuals (75 males and 75 females) were subjected to digital SMV radiography. FM in the resultant image was assessed for longitudinal and transverse diameters, circumference, and area. Also, one particular shape was assigned to each image based on the classification of Chethan et al. of FM shapes. Three qualified oral radiologists performed all the measurements twice within an interval of 10 days. Results and Conclusion: The values obtained for all four parameters were statistically significant and higher in males than in females. The most common morphology of FM was an egg shape while hexagonal was the least common morphology. Circumference was the best indicator of sex followed by area, transverse diameter, and longitudinal diameter. Having achieved a high accuracy of 67.3% with digital SMV radiograph makes it a reliable and reproducible alternative to dry skulls for sex determination. PMID:28123285

  1. Twenty years after International Conference on Population and Development: where are we with adolescent sexual and reproductive health and rights?

    PubMed

    Chandra-Mouli, Venkatraman; Svanemyr, Joar; Amin, Avni; Fogstad, Helga; Say, Lale; Girard, Françoise; Temmerman, Marleen

    2015-01-01

    The International Conference on Population and Development in Cairo in 1994 laid out a bold, clear, and comprehensive definition of reproductive health and called for nations to meet the educational and service needs of adolescents to enable them to deal in a positive and responsible way with their sexuality. In the context of the ongoing review of the International Conference on Population and Development Programme of Action and the considerations for a post-2015 development agenda, this article summarizes the findings of the articles presented in this volume and identifies key challenges and critical answers that need to be tackled in addressing adolescent sexual and reproductive health and rights. The key recommendations are to link the provision of sexuality education and sexual and reproductive health (SRH) services; build awareness, acceptance, and support for youth-friendly SRH education and services; address gender inequality in terms of beliefs, attitudes, and norms; and target the early adolescent period (10-14 years). The many knowledge gaps, however, point to the pressing need for further research on how to best design effective adolescent SRH intervention packages and how best to deliver them.

  2. Sex in an uncertain world: environmental stochasticity helps restore competitive balance between sexually and asexually reproducing populations.

    PubMed

    Park, A W; Vandekerkhove, J; Michalakis, Y

    2014-08-01

    Like many organisms, individuals of the freshwater ostracod species Eucypris virens exhibit either obligate sexual or asexual reproductive modes. Both types of individual routinely co-occur, including in the same temporary freshwater pond (their natural habitat in which they undergo seasonal diapause). Given the well-known two-fold cost of sex, this begs the question of how sexually reproducing individuals are able to coexist with their asexual counterparts in spite of such overwhelming costs. Environmental stochasticity in the form of 'false dawn' inundations (where the first hydration is ephemeral and causes loss of early hatching individuals) may provide an advantage to the sexual subpopulation, which shows greater variation in hatching times following inundation. We explore the potential role of environmental stochasticity in this system using life-history data analysis, climate data, and matrix projection models. In the absence of environmental stochasticity, the population growth rate is significantly lower in sexual subpopulations. Climate data reveal that 'false dawn' inundations are common. Using matrix projection modelling with and without environmental stochasticity, we demonstrate that this phenomenon can restore appreciable balance to the system, in terms of population growth rates. This provides support for the role of environmental stochasticity in helping to explain the maintenance of sex and the occurrence of geographical parthenogenesis.

  3. Large Martian regolith water content implied by rampart crater population

    NASA Astrophysics Data System (ADS)

    Stewart, S. T.; Ahrens, T. J.; O'Keefe, J. D.

    2001-12-01

    We estimate the global regolith water content using a new model for rampart crater formation (Stewart et al.~LPSC 2001). The Martian surface has a high fraction (probably significantly >20%) of craters with so-called fluidized ejecta blankets, characterized by the appearance of ground-hugging flow terminating in one or more continuous distal ramparts. While rampart craters have long held the promise of revealing information about the water content of the Martian regolith, the lack of a comprehensive physical model for the formation of fluidized ejecta blankets has hindered quantitative studies. We have developed a model for rampart crater formation based on ice shock data obtained at Martian temperatures and numerical simulations of impacts onto ice-rock mixtures under Martian conditions. We find that significant quantities of liquid water may be produced by an impact event and that the excavation process is modified by the presence of interstitial ice. As a result, single or multiple rampart ejecta blankets do not require the presence of pre-existing water in the liquid phase. A few to several volume percent of shock-produced liquid water may be incorporated into the continuous ejecta blanket for average impact conditions and reasonable regolith pore space assumptions, e.g. 15~vol% ice-filled near-surface pores. For a given diameter rampart crater, we calculate the associated minimum regolith ice content. Using the Viking-based rampart crater database by Barlow and Bradley (1990), the observed rampart crater population ( ~20% of all craters) implies a minimum regolith ice content of order 0.1~m global layer equivalent. The Mars Orbiter Laser Altimeter (MOLA) data suggest that a much larger fraction of craters, especially in the northern plains, may have rampart ejecta features. To derive the implied global regolith ice content, we correct for the impact flux rate over the past ~3~Ga using a number density for 1-10~km diameter craters, the peak rampart crater size

  4. The interplay between local ecology, divergent selection, and genetic drift in population divergence of a sexually antagonistic female trait.

    PubMed

    Green, Kristina Karlsson; Svensson, Erik I; Bergsten, Johannes; Härdling, Roger; Hansson, Bengt

    2014-07-01

    Genetically polymorphic species offer the possibility to study maintenance of genetic variation and the potential role for genetic drift in population divergence. Indirect inference of the selection regimes operating on polymorphic traits can be achieved by comparing population divergence in neutral genetic markers with population divergence in trait frequencies. Such an approach could further be combined with ecological data to better understand agents of selection. Here, we infer the selective regimes acting on a polymorphic mating trait in an insect group; the dorsal structures (either rough or smooth) of female diving beetles. Our recent work suggests that the rough structures have a sexually antagonistic function in reducing male mating attempts. For two species (Dytiscus lapponicus and Graphoderus zonatus), we could not reject genetic drift as an explanation for population divergence in morph frequencies, whereas for the third (Hygrotus impressopunctatus) we found that divergent selection pulls morph frequencies apart across populations. Furthermore, population morph frequencies in H. impressopunctatus were significantly related to local bioclimatic factors, providing an additional line of evidence for local adaptation in this species. These data, therefore, suggest that local ecological factors and sexual conflict interact over larger spatial scales to shape population divergence in the polymorphism.

  5. Sexual satisfaction in the elderly female population: A special focus on women with gynecologic pathology

    PubMed Central

    Ratner, Elena S.; Erekson, Elisabeth A.; Minkin, Mary Jane; Foran-Tuller, Kelly A.

    2013-01-01

    Sexual function in aging women Sexuality is an integral part of human expressions. Mental health plays a major role in sexuality. Several psychological interventions are proposed to increase the sexual quality of life in older women with diverse gynecologic pathology. A biopsychosocial approach utilizing brief strategies can be easily implemented in clinics to help women of all ages increase their sexual quality of life. The impact of female pelvic floor disorders on sexual function in older women Female pelvic floor disorders include urinary incontinence, pelvic organ prolapse, and fecal incontinence. These disorders increase dramatically with increasing age. Urinary incontinence has been demonstrated to have a negative impact on a woman’s sexual function. Among sexually active older women with urinary incontinence, 22% report being moderately or extremely worried that sexual activity would cause urine loss. An increased prevalence of sexual distress [9% (6/76) vs. 1.3% (2/216), p=0.005] has been reported in sexually active women over 40 years old with urinary incontinence. Treatment of urinary incontinence can improve sexual function in older women. Among sexually active women (N=53) who underwent midurethral slings procedures for the correction of urinary incontinence, increased coital frequency, decrease fear of incontinence with coitus, decreased embarrassment due to incontinence was reported six months after surgery. Pelvic organ prolapse, a hernia of the vagina resulting in a visible vaginal bulge, has also been associated with a negative impact on sexual function. Women with advanced pelvic organ prolapse (POP-Q stage III or IV) have been demonstrated to have decreased body image reporting that they are more self-conscious about their appearance [adjusted odds ratio (AOR) 4.7; 95% confidence interval (CI) 2.9, 51], feel less feminine (AOR 4.0; 95% CI 1.2, 15) and less sexually attractive (AOR 4.6; 95% CI 1.4, 17) compared with women who have normal pelvic

  6. Abortion Research: Attitudes, Sexual Behavior, and Problems in a Community College Population.

    ERIC Educational Resources Information Center

    Bryan, Janice Westlund; Freed, Florence Wallach

    1993-01-01

    Surveys of 70 male and 80 female community college students about their attitudes toward abortion, sexual behavior, and life problems support abortion rights. Antiabortion students were more religious, less sexually active, and less likely to know someone who had an abortion. Many students currently experienced serious problems. (SLD)

  7. Adjustment among mothers reporting same-gender sexual partners: a study of a representative population sample from Quebec Province (Canada).

    PubMed

    Julien, Danielle; Jouvin, Emilie; Jodoin, Emilie; L'archevêque, Alexandre; Chartrand, Elise

    2008-12-01

    We examined the well-being of mothers and non-mothers reporting exclusive opposite-gender sexual partners (OG), same-gender sexual partners (SG), or both (BI) in a representative sample of 20,773 participants (11,034 women) 15-years-old or older from the population of Quebec province in Canada. Participants completed a self-administered questionnaire and SG and BI women (n = 179) were matched to a sample of OG women (n = 179) based on age, income, geographical area, and children (having at least one 18-year-old or younger biological or adopted child at home). We assessed social milieu variables, risk factors for health disorders, mental health, and quality of mothers' relationship with children. The findings indicated a sexual orientation main effect: Mothers and non-mothers in the SG and BI group, as compared to their OG controls, were significantly less likely to live in a couple relationship, had significantly lower levels of social support, higher prevalence of early negative life events, substance abuse, suicide ideation, and higher levels of psychological distress. There were no Sexual Orientation X Parenthood status effects. The results further indicated that sexual orientation did not account for unique variance in women's psychological distress beyond that afforded by their social milieu, health risk factors, and parenthood status. No significant differences were found for the quality of mothers' relationship with children. SG-BI and OG mothers with low levels of social integration were significantly more likely to report problems with children than parents with high levels of social integration. We need to understand how marginal sexualities and their associated social stigma, as risk indicators for mothers, interact with other factors to impact family life, parenting skills, and children's adjustment.

  8. Measuring a hidden population: A novel technique to estimate the population size of women with sexual violence-related pregnancies in South Kivu Province, Democratic Republic of Congo.

    PubMed

    Johnston, Lisa G; McLaughlin, Katherine R; Rouhani, Shada A; Bartels, Susan A

    2017-03-01

    Successive sampling (SS)-population size estimation (PSE) is a technique used to estimate the sizes of hidden populations using data collected in respondent-driven sampling (RDS) surveys. We assess past estimations and use new data from an RDS survey to calculate a new PSE. In 2012, 852 adult women in South Kivu Province, Democratic Republic of Congo, who self-identified as survivors of sexual violence, resulting in a pregnancy, since the start of the war (in 1996) were sampled using RDS. We used imputed visibility, enrollment order, and prior estimates for PSE using SS-PSE in RDS Analyst. Prior estimates varied between Congolese local experts and researchers. We calculated the PSE of women with a sexual violence-related pregnancy in South Kivu using researchers' priors to be approximately 17,400. SS-PSE is an effective method for estimating the population sizes of hidden populations, useful for providing evidence for services and resource allocation. SS-PSE is beneficial because population sizes can be calculated after conducting the survey and do not rely on separate studies or additional data (as in network scale-up, multiplier, and capture-recapture methods).

  9. Sexual Cannibalism: High Incidence in a Natural Population with Benefits to Females

    PubMed Central

    Rabaneda-Bueno, Rubén; Rodríguez-Gironés, Miguel Á.; Aguado-de-la-Paz, Sara; Fernández-Montraveta, Carmen; De Mas, Eva; Wise, David H.; Moya-Laraño, Jordi

    2008-01-01

    Background Sexual cannibalism may be a form of extreme sexual conflict in which females benefit more from feeding on males than mating with them, and males avoid aggressive, cannibalistic females in order to increase net fitness. A thorough understanding of the adaptive significance of sexual cannibalism is hindered by our ignorance of its prevalence in nature. Furthermore, there are serious doubts about the food value of males, probably because most studies that attempt to document benefits of sexual cannibalism to the female have been conducted in the laboratory with non-natural alternative prey. Thus, to understand more fully the ecology and evolution of sexual cannibalism, field experiments are needed to document the prevalence of sexual cannibalism and its benefits to females. Methodology/Principal Findings We conducted field experiments with the Mediterranean tarantula (Lycosa tarantula), a burrowing wolf spider, to address these issues. At natural rates of encounter with males, approximately a third of L. tarantula females cannibalized the male. The rate of sexual cannibalism increased with male availability, and females were more likely to kill and consume an approaching male if they had previously mated with another male. We show that females benefit from feeding on a male by breeding earlier, producing 30% more offspring per egg sac, and producing progeny of higher body condition. Offspring of sexually cannibalistic females dispersed earlier and were larger later in the season than spiderlings of non-cannibalistic females. Conclusions/Significance In nature a substantial fraction of female L. tarantula kill and consume approaching males instead of mating with them. This behaviour is more likely to occur if the female has mated previously. Cannibalistic females have higher rates of reproduction, and produce higher-quality offspring, than non-cannibalistic females. Our findings further suggest that female L. tarantula are nutrient-limited in nature and that

  10. Sexual selection has minimal impact on effective population sizes in species with high rates of random offspring mortality: an empirical demonstration using fitness distributions

    PubMed Central

    Pischedda, Alison; Friberg, Urban; Stewart, Andrew D.; Miller, Paige M.; Rice, William R.

    2015-01-01

    The effective population size (Ne) is a fundamental parameter in population genetics that influences the rate of loss of genetic diversity. Sexual selection has the potential to reduce Ne by causing the sex-specific distributions of individuals that successfully reproduce to diverge. To empirically estimate the effect of sexual selection on Ne, we obtained fitness distributions for males and females from an outbred, laboratory-adapted population of Drosophila melanogaster. We observed strong sexual selection in this population (the variance in male reproductive success was ∼14 times higher than that for females), but found that sexual selection had only a modest effect on Ne, which was 75% of the census size. This occurs because the substantial random offspring mortality in this population diminishes the effects of sexual selection on Ne, a result that necessarily applies to other high fecundity species. The inclusion of this random offspring mortality creates a scaling effect that reduces the variance/mean ratios for male and female reproductive success and causes them to converge. Our results demonstrate that measuring reproductive success without considering offspring mortality can underestimate Ne and overestimate the genetic consequences of sexual selection. Similarly, comparing genetic diversity among different genomic components may fail to detect strong sexual selection. PMID:26374275

  11. Sexual dimorphism in human cranial trait scores: effects of population, age, and body size.

    PubMed

    Garvin, Heather M; Sholts, Sabrina B; Mosca, Laurel A

    2014-06-01

    Sex estimation from the skull is commonly performed by physical and forensic anthropologists using a five-trait scoring system developed by Walker. Despite the popularity of this method, validation studies evaluating its accuracy across a variety of samples are lacking. Furthermore, it remains unclear what other intrinsic or extrinsic variables are related to the expression of these traits. In this study, cranial trait scores and postcranial measurements were collected from four diverse population groups (U.S. Whites, U.S. Blacks, medieval Nubians, and Arikara Native Americans) following Walker's protocols (total n = 499). Univariate and multivariate analyses were utilized to evaluate the accuracy of these traits in sex estimation, and to test for the effects of population, age, and body size on trait expressions. Results revealed significant effects of population on all trait scores. Sample-specific correct sex classification rates ranged from 74% to 94%, with an overall accuracy of 85% for the pooled sample. Classification performance varied among the traits (best for glabella and mastoid scores and worst for nuchal scores). Furthermore, correlations between traits were weak or nonsignificant, suggesting that different factors may influence individual traits. Some traits displayed correlations with age and/or postcranial size that were significant but weak, and within-population analyses did not reveal any consistent relationships between these traits across all groups. These results indicate that neither age nor body size plays a large role in trait expression, and thus does not need to be incorporated into sex estimation methods.

  12. Bridging populations-sexual risk behaviors and HIV prevalence in clients and partners of female sex workers, Bangkok, Thailand 2007.

    PubMed

    Shah, Neha S; Shiraishi, Ray W; Subhachaturas, Wonchart; Anand, Abhijeet; Whitehead, Sara J; Tanpradech, Suvimon; Manopaiboon, Chomnad; Sabin, Keith M; Fox, Kimberley K; Kim, Andrea Y

    2011-06-01

    The aim of this study is to estimate HIV prevalence and assess sexual behaviors in a high-risk and difficult-to-reach population of clients of female sex workers (FSWs). A modified variation of respondent-driven sampling was conducted among FSWs in Bangkok, where FSWs recruited 3 FSW peers, 1 client, and 1 nonpaying partner. After informed consent was obtained, participants completed a questionnaire, were HIV-tested, and were asked to return for results. Analyses were weighted to control for the design of the survey. Among 540 FSWs, 188 (35%) recruited 1 client, and 88 (16%) recruited 1 nonpaying partner. Clients' median age was 38 years. HIV prevalence was 20% and was associated with younger age at first sexual experience [relative risk (RR) = 3.10, 95% confidence interval (CI) 1.16-8.24] and condom use during last sexual encounter with regular partner (RR = 3.97, 95% CI 1.09-14.61). Median age of nonpaying partners was 34 years, and HIV prevalence was 15.1%. There were 56 discordant FSW-client pairs and 14 discordant FSW-nonpaying partner pairs. Condom use was relatively high among discordant FSW-client pairs (90.1%) compared to discordant FSW-nonpaying partner pairs (18.7%). Results suggest that sexual partners of FSWs have a high HIV prevalence and can be a bridge for HIV transmission to other populations. Findings also highlight the importance of initiating surveillance and targeted programs for FSW partners, and demonstrate a recruitment method for hard-to-reach populations.

  13. Bowel, Urinary, and Sexual Problems Among Long-Term Prostate Cancer Survivors: A Population-Based Study

    SciTech Connect

    Mols, Floortje Korfage, Ida J.; Vingerhoets, Ad J.J.M.; Kil, Paul J.M.; Coebergh, Jan Willem W.; Essink-Bot, Marie-Louise; Poll-Franse, Lonneke V. van de

    2009-01-01

    Purpose: To obtain insight into the long-term (5- to 10-year) effects of prostate cancer and treatment on bowel, urinary, and sexual function, we performed a population-based study. Prostate-specific function was compared with an age-matched normative population without prostate cancer. Methods and Materials: Through the population-based Eindhoven Cancer Registry, we selected all men diagnosed with prostate cancer between 1994 and 1998 in the southern Netherlands. In total, 964 patients, alive in November 2004, received questionnaire; 780 (81%) responded. Results: Urinary problems were most common after a prostatectomy; bowel problems were most common after radiotherapy. Compared with an age-matched normative population both urinary and bowel functioning and bother were significantly worse among survivors. Urinary incontinence was reported by 23-48% of survivors compared with 4% of the normative population. Bowel leakage occurred in 5-14% of patients compared with 2% of norms. Erection problems occurred in 40-74% of patients compared with 18% of norms. Conclusions: These results form an important contribution to the limited information available on prostate-specific problems in the growing group of long-term prostate cancer survivors. Bowel, urinary, and sexual problems occur more often among long-term survivors compared with a reference group and cannot be explained merely by age. Because these problems persist for many years, urologists should provide patients with adequate information before treatment. After treatment, there should be an appropriate focus on these problems.

  14. Limited Sexual Reproduction and Quick Turnover in the Population Genetic Structure of Phytophthora infestans in Fujian, China.

    PubMed

    Zhu, Wen; Yang, Li-Na; Wu, E-Jiao; Qin, Chun-Fang; Shang, Li-Ping; Wang, Zong-Hua; Zhan, Jiasui

    2015-05-13

    The mating system plays an important role in the spatiotemporal dynamics of pathogen populations through both its direct and indirect impact on the generation and distribution of genetic variation. Here, we used a combination of microsatellite and phenotypic markers to investigate the spatiotemporal distribution of genetic variation in Phytophthora infestans isolates collected from Fujian, China and to determine the role of sexual reproduction in the dynamics. Although the pathogen populations in this region were dominated by self-fertile genotypes, sexual reproduction only occurred occasionally and its contributions to the population genetic structure of P. infestans and epidemics of late blight in the region were limited. Only 49 genotypes were detected among the 534 isolates assayed and the pathogen populations displayed significant heterozygosity excess. Hierarchical analysis revealed that 21.42% of genetic variation was attributed to the difference among sampling years while only 4.45% was attributed to the difference among locations, suggesting temporal factors play a more important role in the population genetic dynamics of P. infestans than spatial factors in this region. We propose that clonal reproduction, combined with founder effects and long distance dispersal of sporangia, is responsible for the observed pattern of spatiotemporal dynamics in P. infestans.

  15. Echo Behavior in Large Populations of Chemical Oscillators

    NASA Astrophysics Data System (ADS)

    Chen, Tianran; Tinsley, Mark R.; Ott, Edward; Showalter, Kenneth

    2016-10-01

    Experimental and theoretical studies are reported, for the first time, on the observation and characterization of echo phenomena in oscillatory chemical reactions. Populations of uncoupled and coupled oscillators are globally perturbed. The macroscopic response to this perturbation dies out with time: At some time τ after the perturbation (where τ is long enough that the response has died out), the system is again perturbed, and the initial response to this second perturbation again dies out. Echoes can potentially appear as responses that arise at 2 τ ,3 τ ,... after the first perturbation. The phase-resetting character of the chemical oscillators allows a detailed analysis, offering insights into the origin of the echo in terms of an intricate structure of phase relationships. Groups of oscillators experiencing different perturbations are analyzed with a geometric approach and in an analytical theory. The characterization of echo phenomena in populations of chemical oscillators reinforces recent theoretical studies of the behavior in populations of phase oscillators [E. Ott et al., Chaos 18, 037115 (2008)]. This indicates the generality of the behavior, including its likely occurrence in biological systems.

  16. The prevalence of Chlamydia trachomatis in a young, sexually-active population.

    PubMed

    Kovacs, G T; Westcott, M; Rusden, J; Asche, V; King, H; Haynes, S E; Moore, E K; Ketelbey, J W

    A prospective study was carried out to determine the prevalence of Chlamydia trachomatis among 1000 sexually-active women at the Family Planning Association Clinic in Melbourne. This organism was isolated from the cervices of 5.1% of screened women. The women were surveyed about their sexual and gynaecological history, and symptoms of discharge or pain. It was found that women who gave positive results for the presence of Chlamydia were younger, and had commenced intercourse at an earlier age. Risk factors of multiple sexual partners, cervical ectopy and symptoms of urethritis were identified. We recommend that women who have more than one sexual partner should ask their partners to use condoms or, failing this, undergo annual screening for Chlamydia by immunofluorescent staining.

  17. Distinct human stem cell populations in small and large intestine.

    PubMed

    Cramer, Julie M; Thompson, Timothy; Geskin, Albert; LaFramboise, William; Lagasse, Eric

    2015-01-01

    The intestine is composed of an epithelial layer containing rapidly proliferating cells that mature into two regions, the small and the large intestine. Although previous studies have identified stem cells as the cell-of-origin for intestinal epithelial cells, no studies have directly compared stem cells derived from these anatomically distinct regions. Here, we examine intrinsic differences between primary epithelial cells isolated from human fetal small and large intestine, after in vitro expansion, using the Wnt agonist R-spondin 2. We utilized flow cytometry, fluorescence-activated cell sorting, gene expression analysis and a three-dimensional in vitro differentiation assay to characterize their stem cell properties. We identified stem cell markers that separate subpopulations of colony-forming cells in the small and large intestine and revealed important differences in differentiation, proliferation and disease pathways using gene expression analysis. Single cells from small and large intestine cultures formed organoids that reflect the distinct cellular hierarchy found in vivo and respond differently to identical exogenous cues. Our characterization identified numerous differences between small and large intestine epithelial stem cells suggesting possible connections to intestinal disease.

  18. Child Sexual Abuse Is Largely Hidden from the Adult Society: An Epidemiological Study of Adolescents' Disclosures

    ERIC Educational Resources Information Center

    Priebe, Gisela; Svedin, Carl Goran

    2008-01-01

    Objectives: The aim of this study was to investigate disclosure rates and disclosure patterns and to examine predictors of non-disclosure in a sample of male and female adolescents with self-reported experiences of sexual abuse. Method: A sample of 4,339 high school seniors (2,324 girls, 2,015 boys) was examined with a questionnaire concerning…

  19. Assessing Health Issues in States with Large Minority Populations.

    PubMed

    Long, Michelle; Menifield, Charles E; Fletcher, Audwin B

    2015-09-01

    Health care spending is often addressed in discussions of budgeting and deficits in the United States. It is important to many Americans that funds allocated for health care spending be allocated and spent in the most efficient and effective manner, leading to improved health outcomes, particularly for underserved populations. Many studies address health care spending, but few address the issue of spending as it relates to societal well-being, or certain health outcomes that adversely impact communities. This study seeks to expand the available literature by analyzing data from national sources at the state level.

  20. Populations and determinants of airborne fungi in large office buildings.

    PubMed Central

    Chao, H Jasmine; Schwartz, Joel; Milton, Donald K; Burge, Harriet A

    2002-01-01

    Bioaerosol concentrations in office environments and their roles in causing building-related symptoms have drawn much attention in recent years. Most bioaerosol studies have been cross-sectional. We conducted a longitudinal study to examine the characteristics of airborne fungal populations and correlations with other environmental parameters in office environments. We investigated four office buildings in Boston, Massachusetts, during 1 year beginning May 1997, recruiting 21 offices with open workstations. We conducted intensive bioaerosol sampling every 6 weeks resulting in 10 sets of measurement events at each workstation, and recorded relative humidity, temperature, and CO2 concentrations continuously. We used principal component analysis (PCA) to identify groups of culturable fungal taxa that covaried in air. Four major groupings (PCA factors) were derived where the fungal taxa in the same groupings shared similar ecological requirements. Total airborne fungal concentrations varied significantly by season (highest in summer, lowest in winter) and were positively correlated with relative humidity and negatively related to CO2 concentrations. The first and second PCA factors had similar correlations with environmental variables compared with total fungi. The results of this study provide essential information on the variability within airborne fungal populations in office environments over time. These data also provide background against which cross-sectional data can be compared to facilitate interpretation. More studies are needed to correlate airborne fungi and occupants' health, controlling for seasonal effects and other important environmental factors. PMID:12153758

  1. Quantifying prion disease penetrance using large population control cohorts.

    PubMed

    Minikel, Eric Vallabh; Vallabh, Sonia M; Lek, Monkol; Estrada, Karol; Samocha, Kaitlin E; Sathirapongsasuti, J Fah; McLean, Cory Y; Tung, Joyce Y; Yu, Linda P C; Gambetti, Pierluigi; Blevins, Janis; Zhang, Shulin; Cohen, Yvonne; Chen, Wei; Yamada, Masahito; Hamaguchi, Tsuyoshi; Sanjo, Nobuo; Mizusawa, Hidehiro; Nakamura, Yosikazu; Kitamoto, Tetsuyuki; Collins, Steven J; Boyd, Alison; Will, Robert G; Knight, Richard; Ponto, Claudia; Zerr, Inga; Kraus, Theo F J; Eigenbrod, Sabina; Giese, Armin; Calero, Miguel; de Pedro-Cuesta, Jesús; Haïk, Stéphane; Laplanche, Jean-Louis; Bouaziz-Amar, Elodie; Brandel, Jean-Philippe; Capellari, Sabina; Parchi, Piero; Poleggi, Anna; Ladogana, Anna; O'Donnell-Luria, Anne H; Karczewski, Konrad J; Marshall, Jamie L; Boehnke, Michael; Laakso, Markku; Mohlke, Karen L; Kähler, Anna; Chambert, Kimberly; McCarroll, Steven; Sullivan, Patrick F; Hultman, Christina M; Purcell, Shaun M; Sklar, Pamela; van der Lee, Sven J; Rozemuller, Annemieke; Jansen, Casper; Hofman, Albert; Kraaij, Robert; van Rooij, Jeroen G J; Ikram, M Arfan; Uitterlinden, André G; van Duijn, Cornelia M; Daly, Mark J; MacArthur, Daniel G

    2016-01-20

    More than 100,000 genetic variants are reported to cause Mendelian disease in humans, but the penetrance-the probability that a carrier of the purported disease-causing genotype will indeed develop the disease-is generally unknown. We assess the impact of variants in the prion protein gene (PRNP) on the risk of prion disease by analyzing 16,025 prion disease cases, 60,706 population control exomes, and 531,575 individuals genotyped by 23andMe Inc. We show that missense variants in PRNP previously reported to be pathogenic are at least 30 times more common in the population than expected on the basis of genetic prion disease prevalence. Although some of this excess can be attributed to benign variants falsely assigned as pathogenic, other variants have genuine effects on disease susceptibility but confer lifetime risks ranging from <0.1 to ~100%. We also show that truncating variants in PRNP have position-dependent effects, with true loss-of-function alleles found in healthy older individuals, a finding that supports the safety of therapeutic suppression of prion protein expression.

  2. Sexual Behaviors and HIV Status: A Population-Based Study Among Older Adults in Rural South Africa

    PubMed Central

    Gómez-Olivé, Francesc X.; Rohr, Julia K.; Houle, Brian C.; Kabudula, Chodziwadziwa W.; Wagner, Ryan G.; Salomon, Joshua A.; Kahn, Kathleen; Berkman, Lisa F.; Tollman, Stephen M.; Bärnighausen, Till

    2017-01-01

    Objective: To identify the unmet needs for HIV prevention among older adults in rural South Africa. Methods: We analyzed data from a population-based sample of 5059 men and women aged 40 years and older from the study Health and Aging in Africa: Longitudinal Studies of INDEPTH Communities (HAALSI), which was carried out in the Agincourt health and sociodemographic surveillance system in the Mpumalanga province of South Africa. We estimated the prevalence of HIV (laboratory-confirmed and self-reported) and key sexual behaviors by age and sex. We compared sexual behavior profiles across HIV status categories with and without age–sex standardization. Results: HIV prevalence was very high among HAALSI participants (23%, 95% confidence interval [CI]: 21 to 24), with no sex differences. Recent sexual activity was common (56%, 95% CI: 55 to 58) across all HIV status categories. Condom use was low among HIV-negative adults (15%, 95% CI: 14 to 17), higher among HIV-positive adults who were unaware of their HIV status (27%, 95% CI: 22 to 33), and dramatically higher among HIV-positive adults who were aware of their status (75%, 95% CI: 70 to 80). Casual sex and multiple partnerships were reported at moderate levels, with slightly higher estimates among HIV-positive compared to HIV-negative adults. Differences by HIV status remained after age–sex standardization. Conclusions: Older HIV-positive adults in an HIV hyperendemic community of rural South Africa report sexual behaviors consistent with high HIV transmission risk. Older HIV-negative adults report sexual behaviors consistent with high HIV acquisition risk. Prevention initiatives tailored to the particular prevention needs of older adults are urgently needed to reduce HIV risk in this and similar communities in sub-Saharan Africa. PMID:27926667

  3. Computing Ro in a population with heterogeneity in sexual activity and proportionate mixing using a STM-solver

    NASA Astrophysics Data System (ADS)

    Gutierrez A., Natalia A.

    2014-06-01

    A model to determinate the reproductive basic number, detonated Ro, for the case of population with heterogeneity in sexual activity and proportionate mixing is solved using computer algebra and SMT solvers. Specifically Maple and Z3 were used. The code for the solution of the model was written in Z3-Python, but it can also be played by Z3-SMT-Lib. Ro represents an algebraic synthesis of every epidemiological parameter. Numerical simulations were done to prove the effectiveness of the model and the code. The algebraic structure of Ro suggests the possible control measurements that should be implemented to avoid the propagation of the sexual transmitted diseases. The obtained results are important on the computational epidemiology field. As a future investigation, it is suggested to apply the STM solvers to analyze models for other kinds of epidemic diseases.

  4. Detecting differential protein expression in large-scale population proteomics

    SciTech Connect

    Ryu, Soyoung; Qian, Weijun; Camp, David G.; Smith, Richard D.; Tompkins, Ronald G.; Davis, Ronald W.; Xiao, Wenzhong

    2014-06-17

    Mass spectrometry-based high-throughput quantitative proteomics shows great potential in clinical biomarker studies, identifying and quantifying thousands of proteins in biological samples. However, methods are needed to appropriately handle issues/challenges unique to mass spectrometry data in order to detect as many biomarker proteins as possible. One issue is that different mass spectrometry experiments generate quite different total numbers of quantified peptides, which can result in more missing peptide abundances in an experiment with a smaller total number of quantified peptides. Another issue is that the quantification of peptides is sometimes absent, especially for less abundant peptides and such missing values contain the information about the peptide abundance. Here, we propose a Significance Analysis for Large-scale Proteomics Studies (SALPS) that handles missing peptide intensity values caused by the two mechanisms mentioned above. Our model has a robust performance in both simulated data and proteomics data from a large clinical study. Because varying patients’ sample qualities and deviating instrument performances are not avoidable for clinical studies performed over the course of several years, we believe that our approach will be useful to analyze large-scale clinical proteomics data.

  5. Sexual selection and alternative mating behaviours generate demographic stochasticity in small populations.

    PubMed Central

    Calsbeek, Ryan; Alonzo, Suzanne H; Zamudio, Kelly; Sinervo, Barry

    2002-01-01

    Recent theory predicts that environmental variation and small population size facilitate the coexistence of alternative phenotypes despite unequal mean fitness. However, traditional studies of reproductive strategies often assume that the stability of alternative mating behaviours relies on equal male fitness. We present results from field observations and experimental manipulations of thermal resources on territories demonstrating the coexistence of alternative reproductive behaviours with unequal fitness. The side-blotched lizard Uta stansburiana exhibits two alternative strategies for territoriality: "usurp" and "defend". Paternity analysis revealed significantly greater mean fitness for "usurpers" than "defenders" in our study of natural variation. Moreover, variance in fitness was significantly higher for usurpers on both experimental and natural plots, implying that "usurp" is a risky strategy with potentially large pay-offs or none at all. We show theoretically that significantly higher variance in usurper fitness can allow for coexistence with defenders despite higher mean fitness of usurpers. This coexistence is facilitated by small population size. Our results have general implications for the evolution of alternative strategies and the maintenance of genetic diversity in small populations. PMID:11798431

  6. [Effects of water temperature and edible algal density on the population dynamics and sexual reproduction of Moina irrasa].

    PubMed

    Li, Yu-Ying; Deng, Dao-Gui; Lei, Juan; Xi, Yi-Long

    2011-12-01

    This paper studied the population dynamics and sexual reproduction of Moina irrasa at different water temperature and edible algal density. The population density of M. irrasa was obviously higher at high than at medium and low densities of edible algae, with the maximum at high edible algal density and 20 degrees C. At the same temperatures, the average number of the offsprings first produced by per female M. irrasa declined with decreasing edible algal density, and the maximum value appeared at 25 degrees C and at high edible algal density. The male offsprings produced were obviously higher at high than at medium and low edible algal densities. There was a significant correlation between the male density and the population density of M. irrasa. The number of ephippia produced by M. irrasa declined with decreasing edible algal density, and was higher at 25 degrees C than at other temperatures. Edible algal density had larger effects on the population dynamics and sexual reproduction of M. irrasa, as compared with temperature.

  7. Comparing cestode infections and their consequences for host fitness in two sexual branchiopods: alien Artemia franciscana and native A. salina from syntopic-populations

    PubMed Central

    Amat, Francisco; Sánchez, Marta I.; Green, Andy J.

    2015-01-01

    The American brine shrimp Artemia franciscana is invasive in the Mediterranean region where it has displaced native species (the sexual A. salina, and the clonal A. parthenogenetica) from many salt pond complexes. Artemia populations are parasitized by numerous avian cestodes whose effects have been studied in native species. We present a study from the Ebro Delta salterns (NE Spain), in a salt pond where both A. franciscana and native A. salina populations coexist, providing a unique opportunity to compare the parasite loads of the two sexual species in syntopy. The native species had consistently higher infection parameters, largely because the dominant cestode in A. salina adults and juveniles (Flamingolepis liguloides) was much rarer in A. franciscana. The most abundant cestodes in the alien species were Eurycestus avoceti (in adults) and Flamingolepis flamingo (in juveniles). The abundance of E. avoceti and F. liguloides was higher in the A. franciscana population syntopic with A. salina than in a population sampled at the same time in another pond where the native brine shrimp was absent, possibly because the native shrimp provides a better reservoir for parasite circulation. Infection by cestodes caused red colouration in adult and juvenile A. salina, and also led to castration in a high proportion of adult females. Both these effects were significantly stronger in the native host than in A. franciscana with the same parasite loads. However, for the first time, significant castration effects (for E. avoceti and F. liguloides) and colour change (for six cestode species) were observed in infected A. franciscana. Avian cestodes are likely to help A. franciscana outcompete native species. At the same time, they are likely to reduce the production of A. franciscana cysts in areas where they are harvested commercially. PMID:26157636

  8. Collective response of human populations to large-scale emergencies.

    PubMed

    Bagrow, James P; Wang, Dashun; Barabási, Albert-László

    2011-03-30

    Despite recent advances in uncovering the quantitative features of stationary human activity patterns, many applications, from pandemic prediction to emergency response, require an understanding of how these patterns change when the population encounters unfamiliar conditions. To explore societal response to external perturbations we identified real-time changes in communication and mobility patterns in the vicinity of eight emergencies, such as bomb attacks and earthquakes, comparing these with eight non-emergencies, like concerts and sporting events. We find that communication spikes accompanying emergencies are both spatially and temporally localized, but information about emergencies spreads globally, resulting in communication avalanches that engage in a significant manner the social network of eyewitnesses. These results offer a quantitative view of behavioral changes in human activity under extreme conditions, with potential long-term impact on emergency detection and response.

  9. Medullary carcinoma of the large intestine: a population based analysis.

    PubMed

    Thirunavukarasu, Pragatheeshwar; Sathaiah, Magesh; Singla, Smit; Sukumar, Shyam; Karunamurthy, Arivarasan; Pragatheeshwar, Kothai Divya; Lee, Kenneth K W; Zeh, Herbert; Kane, Kevin M; Bartlett, David L

    2010-10-01

    Medullary carcinoma (MC) of the colorectum is a relatively new histological type of adenocarcinoma characterized by poor glandular differentiation and intraepithelial lymphocytic infiltrate. To date, there has been no epidemiological study of this rare tumor type, which has now been incorporated as a separate entity in the World Health Organization (WHO) classification of colorectal cancers. We used the population-based registries of the Surveillance, Epidemiology and End Results (SEER) database to identify all cases of colorectal MC between 1973 and 2006 and compared them to poorly and undifferentiated colonic adenocarcinomas (PDA and UDA, respectively). We observed that MCs were rare tumors, constituting approximately 5-8 cases for every 10,000 colon cancers diagnosed, with a mean annual incidence of 3.47 (+/-0.75) per 10 million population. Mean age at diagnosis was 69.3 (+/-12.5) years, with incidence increasing with age. MCs were twice as common in females, who presented at a later age, with a lower stage and a trend towards favorable prognosis. MCs were extremely rare among African-Americans. MCs were most common in the proximal colon (74%), where they present at a later age than the sigmoid colon. There were no cases reliably identified in the rectum or appendix. Serum carcinoembryonic antigen levels (CEA) were elevated prior to first course of treatment in 40% of the patients. MCs were more commonly poorly differentiated (72%), with 22% being undifferentiated. MCs commonly presented with Stage II disease, with 10% presenting with metastases. Only one patient presented with N2b disease (>7 positive nodes). Early outcome analyses showed that MCs have 1- and 2-year relative survival rates of 92.7 and 73.8% respectively. Although MCs showed a trend towards better early overall survival, undifferentiated MCs present more commonly with Stage III, with comparatively worse early outcomes.

  10. Insertion Polymorphisms of Mobile Genetic Elements in Sexual and Asexual Populations of Daphnia pulex

    PubMed Central

    Ye, Zhiqiang; Lynch, Michael

    2017-01-01

    Transposable elements (TEs) constitute a substantial portion of many eukaryotic genomes, and can in principle contribute to evolutionary innovation as well as genomic deterioration. Daphnia pulex serves as a useful model for studying TE dynamics as a potential cause and/or consequence of asexuality. We analyzed insertion polymorphisms of TEs in 20 sexual and 20 asexual isolates of D. pulex across North American from their available whole-genome sequencing data. Our results show that the total fraction of the derived sequences of TEs is not substantially different between asexual and sexual D. pulex isolates. However, in general, sexual clones contain fewer fixed TE insertions but more total insertion polymorphisms than asexual clones, supporting the hypothesis that sexual reproduction facilitates the spread and elimination of TEs. We identified nine asexual-specific fixed TE insertions, eight long terminal repeat retrotransposons, and one DNA transposon. By comparison, no sexual-specific fixed TE insertions were observed in our analysis. Furthermore, except one TE insertion located on a contig from chromosome 7, the other eight asexual-specific insertion sites are located on contigs from chromosome 9 that is known to be associated with obligate asexuality in D. pulex. We found that all nine asexual-specific fixed TE insertions can also be detected in some Daphnia pulicaria isolates, indicating that a substantial number of TE insertions in asexual D. pulex have been directly inherited from D. pulicaria during the origin of obligate asexuals. PMID:28057730

  11. Insertion Polymorphisms of Mobile Genetic Elements in Sexual and Asexual Populations of Daphnia pulex.

    PubMed

    Jiang, Xiaoqian; Tang, Haixu; Ye, Zhiqiang; Lynch, Michael

    2017-02-01

    Transposable elements (TEs) constitute a substantial portion of many eukaryotic genomes, and can in principle contribute to evolutionary innovation as well as genomic deterioration. Daphnia pulex serves as a useful model for studying TE dynamics as a potential cause and/or consequence of asexuality. We analyzed insertion polymorphisms of TEs in 20 sexual and 20 asexual isolates of D. pulex across North American from their available whole-genome sequencing data. Our results show that the total fraction of the derived sequences of TEs is not substantially different between asexual and sexual D. pulex isolates. However, in general, sexual clones contain fewer fixed TE insertions but more total insertion polymorphisms than asexual clones, supporting the hypothesis that sexual reproduction facilitates the spread and elimination of TEs. We identified nine asexual-specific fixed TE insertions, eight long terminal repeat retrotransposons, and one DNA transposon. By comparison, no sexual-specific fixed TE insertions were observed in our analysis. Furthermore, except one TE insertion located on a contig from chromosome 7, the other eight asexual-specific insertion sites are located on contigs from chromosome 9 that is known to be associated with obligate asexuality in D. pulex. We found that all nine asexual-specific fixed TE insertions can also be detected in some Daphnia pulicaria isolates, indicating that a substantial number of TE insertions in asexual D. pulex have been directly inherited from D. pulicaria during the origin of obligate asexuals.

  12. The Influence of Cultural Adaptation and Sexual Risk Behaviors on Cervical Cytology in a Hispanic Population

    PubMed Central

    Ward, Kristy K.; Roncancio, Angelica M.; Breitkopf, Carmen Radecki

    2010-01-01

    OBJECTIVE To determine if the level of cultural adaptation (acculturation) of Hispanic women is associated with increased sexual risk behaviors and cervical cytological abnormalities. METHODS Hispanic women 18 to 55 years of age (mean = 30.5 ± 8.32) underwent routine Papanicoulaou (Pap) testing and completed a comprehensive survey (N=3149). Acculturation (cultural adaptation) was measured using the Short Acculturation Scale for Hispanics. Structural equation modeling (SEM) was employed to test a mediation model. RESULTS Highly acculturated women engaged in a greater number of sexual risk behaviors and were more likely to have an abnormal Pap test when compared to less acculturated Hispanic women (p < .001). CONCLUSION Acculturation is related to sexual risk taking and abnormal cervical cytology. Determination of acculturation level as part of culturally competent healthcare will aid in tailoring patient communication and counseling on the prevention of cervical cancer among Hispanic women. PMID:20864073

  13. Sexual harassment victimization and perpetration among high school students.

    PubMed

    Clear, Emily R; Coker, Ann L; Cook-Craig, Patricia G; Bush, Heather M; Garcia, Lisandra S; Williams, Corrine M; Lewis, Alysha M; Fisher, Bonnie S

    2014-10-01

    This large, population-based study is one of the few to examine prevalence rates of sexual harassment occurring during the past 12 months by victimization and perpetration among adolescents. In this large, cross-sectional survey of students attending 26 high schools, sexual harassment was defined using three questions from the Sexual Experiences Questionnaire. Among 18,090 students completing the survey, 30% disclosed sexual harassment victimization (37% of females, 21% of males) and 8.5% reported perpetration (5% of females, 12% of males). Sexual harassment perpetration was highly correlated with male sex, minority race/ethnicity, same-sex attraction, bullying, alcohol binge drinking, and intraparental partner violence.

  14. Dynamics of airborne fungal populations in a large office building

    NASA Technical Reports Server (NTRS)

    Burge, H. A.; Pierson, D. L.; Groves, T. O.; Strawn, K. F.; Mishra, S. K.

    2000-01-01

    The increasing concern with bioaerosols in large office buildings prompted this prospective study of airborne fungal concentrations in a newly constructed building on the Gulf coast. We collected volumetric culture plate air samples on 14 occasions over the 18-month period immediately following building occupancy. On each sampling occasion, we collected duplicate samples from three sites on three floors of this six-story building, and an outdoor sample. Fungal concentrations indoors were consistently below those outdoors, and no sample clearly indicated fungal contamination in the building, although visible growth appeared in the ventilation system during the course of the study. We conclude that modern mechanically ventilated buildings prevent the intrusion of most of the outdoor fungal aerosol, and that even relatively extensive air sampling protocols may not sufficiently document the microbial status of buildings.

  15. Sexual dimorphism of the humerus in contemporary Cretans--a population-specific study and a review of the literature*.

    PubMed

    Kranioti, Elena F; Michalodimitrakis, Manolis

    2009-09-01

    Sex determination is the first essential step for positive identification when a decomposed body is recovered. Taking into consideration the population aspect of sexual dimorphism of the skeleton, the present study aimed to create a sex identification technique using osteometric standards, derived from a contemporary Cretan population. A total of 168 left humeri were measured according to standard osteometric techniques. The differences between the means in males and females were significant (p < 0.0005). About 92.3% of cases were correctly classified when all measurements were applied jointly. Stepwise procedure produced an accuracy rate of 92.9%. The most effective single dimension was vertical head diameter (89.9%). The current study provides standards for a population that has not been represented so far in the existing databases. It demonstrates that the humerus is an effective bone for the estimation of sex because even in a fragmentary state it can give high classification accuracy.

  16. Psychopharmacology of male rat sexual behavior: modeling human sexual dysfunctions?

    PubMed

    Olivier, B; Chan, J S W; Pattij, T; de Jong, T R; Oosting, R S; Veening, J G; Waldinger, M D

    2006-01-01

    Most of our current understanding of the neurobiology, neuroanatomy and psychopharmacology of sexual behavior and ejaculatory function has been derived from preclinical studies in the rat. When a large population of male rats is tested on sexual activity during a number of successive tests, over time individual rats display a very stable sexual behavior that is either slow, normal or fast as characterized by the number of ejaculations performed. These sexual endophenotypes are postulated as rat counterparts of premature (fast rats) or retarded ejaculation (slow rats). Psychopharmacology in these endophenotypes helps to delineate the underlying mechanisms and pathology. This is illustrated by the effects of serotonergic antidepressants and serotonergic compounds on sexual and ejaculatory behavior of rats. These preclinical studies and models contribute to a better understanding of the neurobiology of ejaculation and boost the development of novel drug targets to treat ejaculatory disorders such as premature and retarded ejaculation.

  17. Different Evolutionary Paths to Complexity for Small and Large Populations of Digital Organisms

    PubMed Central

    2016-01-01

    A major aim of evolutionary biology is to explain the respective roles of adaptive versus non-adaptive changes in the evolution of complexity. While selection is certainly responsible for the spread and maintenance of complex phenotypes, this does not automatically imply that strong selection enhances the chance for the emergence of novel traits, that is, the origination of complexity. Population size is one parameter that alters the relative importance of adaptive and non-adaptive processes: as population size decreases, selection weakens and genetic drift grows in importance. Because of this relationship, many theories invoke a role for population size in the evolution of complexity. Such theories are difficult to test empirically because of the time required for the evolution of complexity in biological populations. Here, we used digital experimental evolution to test whether large or small asexual populations tend to evolve greater complexity. We find that both small and large—but not intermediate-sized—populations are favored to evolve larger genomes, which provides the opportunity for subsequent increases in phenotypic complexity. However, small and large populations followed different evolutionary paths towards these novel traits. Small populations evolved larger genomes by fixing slightly deleterious insertions, while large populations fixed rare beneficial insertions that increased genome size. These results demonstrate that genetic drift can lead to the evolution of complexity in small populations and that purifying selection is not powerful enough to prevent the evolution of complexity in large populations. PMID:27923053

  18. Extending Sexual Objectification Theory and Research to Minority Populations, Couples, and Men

    ERIC Educational Resources Information Center

    Heimerdinger-Edwards, Sarah R.; Vogel, David L.; Hammer, Joseph H.

    2011-01-01

    This reaction highlights several strengths of this major contribution and discusses some future directions in this line of research. The authors offer research ideas in the areas of cultural and cross-cultural issues, couples and relationships, as well as direct and indirect effects of sexual objectification on men. In terms of providing…

  19. The Prevalence of a History of Childhood Sexual Abuse in an Acute Adult Inpatient Population.

    ERIC Educational Resources Information Center

    Wurr, Catherine J.; Partridge, Ian M.

    1996-01-01

    In a survey of 120 inpatients admitted to a United Kingdom acute psychiatric ward, 46% reported a history of childhood sexual abuse. Only 14%, however, had disclosed the abuse previously to psychiatrists. The patterns of abuse were found to correspond with those causing problems with adjustment in adult life. (CR)

  20. The Link between Childhood Sexual Abuse and Myocardial Infarction in a Population-Based Study

    ERIC Educational Resources Information Center

    Fuller-Thomson, Esme; Bejan, Raluca; Hunter, John T.; Grundland, Tamara; Brennenstuhl, Sarah

    2012-01-01

    Objectives: This study examined the relationship between childhood sexual abuse (CSA) and myocardial infarction in men and women, while controlling for social determinants (i.e., socioeconomic status, social support, mental health) and traditional cardiovascular risk factors (i.e., age, race, obesity, smoking, physical inactivity, diabetes…

  1. Sexual and geographic organisation of men who have sex with men in a large East African city: opportunities for outreach

    PubMed Central

    Ross, Michael W; Nyoni, Joyce; Bowen, Anne M; Williams, Mark L; Kashiha, John J

    2012-01-01

    Objectives To describe geographical and dispersion patterns of men who have sex with men (MSM)-related venues in a large East African city and their associations with times, participants and venue type. Methods Mapping of MSM sites in Dar es Salaam was carried out by community research workers who catalogued, observed and reported data on venue sites, formality, times of operation, type of participant, police or vigilante activity, length of operation and the degree to which it is known both in and outside the MSM and gay communities. Results There is a large and widely disseminated MSM/gay satellite cultures of at least 98 sites, which has some formal sites, but is largely informal and operates within mixed entertainment environments and at particular times (including some weekend-only locales) across the city. There is a mix of places for sexual contact, largely social venues and sex on location sites. Cruising appears to be limited to open spaces and parks, with no vehicular component and almost no internet component. They are widely disseminated across all suburbs and there is no central location for MSM activities. MSM sex workers (SWs) operate at a third of these sites. Conclusions There is a large number of ‘local’ MSM contact, social and sex sites and any work with MSM will have to include these less-formal and less-known sites. The widely disseminated nature of the MSM sites, however, also suggests that sexual networks may not be closely linked between sites. The climate of stigma, abuse and potential violence appear to be limiting the development of more formal sites. This pattern is probably typical of other large urban areas in East Africa and perhaps across sub-Saharan Africa (SSA). PMID:23180391

  2. Smoking and intention to quit among a large sample of black sexual and gender minorities.

    PubMed

    Jordan, Jenna N; Everett, Kevin D; Ge, Bin; McElroy, Jane A

    2015-01-01

    The purpose of this study is to more completely quantify smoking and intention to quit from a sample of sexual and gender minority (SGM) Black individuals (N = 639) through analysis of data collected at Pride festivals and online. Frequencies described demographic characteristics; chi-square analyses were used to compare tobacco-related variables. Black SGM smokers were more likely to be trying to quit smoking than White SGM smokers. However, Black SGM individuals were less likely than White SGM individuals to become former smokers. The results of this study indicate that smoking behaviors may be heavily influenced by race after accounting for SGM status.

  3. Highly Recombinant VGII Cryptococcus gattii Population Develops Clonal Outbreak Clusters through both Sexual Macroevolution and Asexual Microevolution

    PubMed Central

    Croll, Daniel; Li, Wenjun; Mieczkowski, Piotr; Carter, Dee A.; Cuomo, Christina A.; Kronstad, James W.

    2014-01-01

    ABSTRACT An outbreak of the fungal pathogen Cryptococcus gattii began in the Pacific Northwest (PNW) in the late 1990s. This outbreak consists of three clonal subpopulations: VGIIa/major, VGIIb/minor, and VGIIc/novel. Both VGIIa and VGIIc are unique to the PNW and exhibit increased virulence. In this study, we sequenced the genomes of isolates from these three groups, as well as global isolates, and analyzed a total of 53 isolates. We found that VGIIa/b/c populations show evidence of clonal expansion in the PNW. Whole-genome sequencing provided evidence that VGIIb originated in Australia, while VGIIa may have originated in South America, and these were likely independently introduced. Additionally, the VGIIa outbreak lineage may have arisen from a less virulent clade that contained a mutation in the MSH2 ortholog, but this appears to have reverted in the VGIIa outbreak strains, suggesting that a transient mutator phenotype may have contributed to adaptation and evolution of virulence in the PNW outbreak. PNW outbreak isolates share genomic islands, both between the clonal lineages and with global isolates, indicative of sexual recombination. This suggests that VGII C. gattii has undergone sexual reproduction, either bisexual or unisexual, in multiple locales contributing to the production of novel, virulent subtypes. We also found that the genomes of two basal VGII isolates from HIV+ patients contain an introgression tract spanning three genes. Introgression substantially contributed to intra-VGII polymorphism and likely occurred through sexual reproduction with VGI. More broadly, these findings illustrate how both microevolution and sexual reproduction play central roles in the development of infectious outbreaks from avirulent or less virulent progenitors. PMID:25073643

  4. Phenology of scramble polygyny in a wild population of chrysomelid beetles: the opportunity for and the strength of sexual selection [corrected].

    PubMed

    Baena, Martha Lucía; Macías-Ordóñez, Rogelio

    2012-01-01

    Recent debate has highlighted the importance of estimating both the strength of sexual selection on phenotypic traits, and the opportunity for sexual selection. We describe seasonal fluctuations in mating dynamics of Leptinotarsa undecimlineata (Coleoptera: Chrysomelidae). We compared several estimates of the opportunity for, and the strength of, sexual selection and male precopulatory competition over the reproductive season. First, using a null model, we suggest that the ratio between observed values of the opportunity for sexual selections and their expected value under random mating results in unbiased estimates of the actual nonrandom mating behavior of the population. Second, we found that estimates for the whole reproductive season often misrepresent the actual value at any given time period. Third, mating differentials on male size and mobility, frequency of male fighting and three estimates of the opportunity for sexual selection provide contrasting but complementary information. More intense sexual selection associated to male mobility, but not to male size, was observed in periods with high opportunity for sexual selection and high frequency of male fights. Fourth, based on parameters of spatial and temporal aggregation of female receptivity, we describe the mating system of L. undecimlineata as a scramble mating polygyny in which the opportunity for sexual selection varies widely throughout the season, but the strength of sexual selection on male size remains fairly weak, while male mobility inversely covaries with mating success. We suggest that different estimates for the opportunity for, and intensity of, sexual selection should be applied in order to discriminate how different behavioral and demographic factors shape the reproductive dynamic of populations.

  5. Erectile dysfunction and phosphodiesterase type 5 inhibitor use: associations with sexual activities, function and satisfaction in a population sample of older men.

    PubMed

    Lee, D M; Nazroo, J; Pendleton, N

    2015-07-01

    The objective of this study was to examine the association between sexual activities, problems and satisfaction, and ED and PDE5 inhibitor (PDE5i) use. A nationally representative sample of men (n=2612) aged 51-87 years from the English Longitudinal Study of Ageing completed an in-depth Sexual Relationships and Activities Questionnaire. Associations between ED and/or PDE5i use and sexual outcomes were explored using logistic regression models adjusted for age, health and lifestyle factors. PDE5i use in the preceding 3 months was reported by a total of 191 (7%) men, whereas 542 (21%) reported ED but no PDE5i use (untreated ED). Compared with men without ED, PDE5i users were more likely to be sexually active and report more frequent sexual intercourse. Men with untreated ED reported the lowest frequency of sexual activities. Compared with men without ED, both PDE5i users and those with untreated ED were more likely to report being concerned about their level of sexual desire, frequency of sexual activities, erectile function, waking erections and orgasmic experience. PDE5i users were also more concerned about and dissatisfied with their overall sex life than men without ED. This population-based study shows that while PDE5i use is associated with improved sexual functioning, this is not equally reflected in decreased levels of concern and dissatisfaction with their overall sexual health. Clinicians should be aware of this disparity between functional gains and continuing sexual concerns and dissatisfaction, and, where appropriate, offer psychosexual counselling as an adjunct to PDE5i medication.

  6. The use of social networking applications of smartphone and associated sexual risks in lesbian, gay, bisexual, and transgender populations: a systematic review.

    PubMed

    Choi, E P H; Wong, J Y H; Fong, D Y T

    2017-02-01

    The use of social networking applications (apps) on smartphones has the potential to impact sexual health and behaviour. This was the first systematic review to critically appraise and summarize the existing literature on the use of social networking apps on smartphones and their associated sexual health and sexual behaviour effects in lesbian, gay, bisexual and transgender populations. A systematic search was conducted in five databases (CINAHL Plus, PsycINFO, PubMed, SCOPUS and Sociological Abstracts), using controlled terms and keywords. Thirteen articles from 11 studies were included in this review. Studied outcomes included rates of unprotected sexual intercourse, the number of sexual partners, drug/alcohol use prior to/during sexual intercourse, sexually transmitted infections (STIs) testing and the prevalence of STIs. Among app users, the prevalence of unprotected sex ranged from 17.0% to 66.7%. The mean number of sexual partners ranged from 1.4 to 2.9 (last 1-month period), and from 46.2 to 79.6 (lifetime). Two studies found that the prevalence of HIV infection was 1.9% and 11.4%, respectively. The self-reported prevalence of prior diagnosis of STIs other than HIV ranged from 9.1% to 51.0%. It should be noted that the heterogeneity of the study design and outcome measures across different studies hindered the comparison of findings across different studies. Furthermore, the findings in some studies are not reliable due to methodological problems. Our results highlight the need for more research with rigorous methodology to understand the negative impacts of using these apps on sexual health and sexual behaviour. For future studies, the operational definition of outcomes, including social networking app use and unprotected anal intercourse (UAI), should be clearly outlined. The use of validated tools to measure sexual behaviour and biological measures of HIV and other STDs is preferable so that outcomes can be standardized to facilitate comparisons between

  7. Identification and analysis of genomic regions with large between-population differentiation in humans.

    PubMed

    Myles, S; Tang, K; Somel, M; Green, R E; Kelso, J; Stoneking, M

    2008-01-01

    The primary aim of genetic association and linkage studies is to identify genetic variants that contribute to phenotypic variation within human populations. Since the overwhelming majority of human genetic variation is found within populations, these methods are expected to be effective and can likely be extrapolated from one human population to another. However, they may lack power in detecting the genetic variants that contribute to phenotypes that differ greatly between human populations. Phenotypes that show large differences between populations are expected to be associated with genomic regions exhibiting large allele frequency differences between populations. Thus, from genome-wide polymorphism data genomic regions with large allele frequency differences between populations can be identified, and evaluated as candidates for large between-population phenotypic differences. Here we use allele frequency data from approximately 1.5 million SNPs from three human populations, and present an algorithm that identifies genomic regions containing SNPs with extreme Fst. We demonstrate that our candidate regions have reduced heterozygosity in Europeans and Chinese relative to African-Americans, and are likely enriched with genes that have experienced positive natural selection. We identify genes that are likely responsible for phenotypes known to differ dramatically between human populations and present several candidates worthy of future investigation. Our list of high Fst genomic regions is a first step in identifying the genetic variants that contribute to large phenotypic differences between populations, many of which have likely experienced positive natural selection. Our approach based on between population differences can compliment traditional within population linkage and association studies to uncover novel genotype-phenotype relationships.

  8. Sexual Trauma Increases the Risk of Developing Psychosis in an Ultra High-Risk “Prodromal” Population

    PubMed Central

    Thompson, Andrew D.

    2014-01-01

    Studies indicate a high prevalence of childhood trauma in patient cohorts with established psychotic disorder and in those at risk of developing psychosis. A causal link between childhood trauma and development of psychosis has been proposed. We aimed to examine the association between experience of childhood trauma and the development of a psychotic disorder in a large “Ultra High Risk” (UHR) for psychosis cohort. The data were collected as part of a longitudinal cohort study of all UHR patients recruited to research studies at the Personal Assessment and Clinical Evaluation clinic between 1993 and 2006. Baseline data were collected at recruitment to these studies. The participants completed a comprehensive follow-up assessment battery (mean time to follow-up 7.5 years, range 2.4–14.9 years), which included the Childhood Trauma Questionnaire (CTQ), a self-report questionnaire that assesses experience of childhood trauma. The outcome of interest was transition to a psychotic disorder during the follow-up period. Data were available on 233 individuals. Total CTQ trauma score was not associated with transition to psychosis. Of the individual trauma types, only sexual abuse was associated with transition to psychosis (P = .02). The association remained when adjusting for potential confounding factors. Those with high sexual abuse scores were estimated to have a transition risk 2–4 times that of those with low scores. The findings suggest that sexual trauma may be an important contributing factor in development of psychosis for some individuals. PMID:23455040

  9. Romantic and Sexual Behavior in Young Adolescents: Repeated Surveys in a Population-Based Cohort

    ERIC Educational Resources Information Center

    Waylen, Andrea E.; Ness, Andrew; McGovern, Phil; Wolke, Dieter; Low, Nicola

    2010-01-01

    Adverse outcomes of teenage sexual activity are common in the United Kingdom. The authors used a computer-assisted interview to ask young adolescents aged 11 to 12 years (N = 6,856) and 12 to 13 years (N = 6,801) who were part of the Avon Longitudinal Study of Parents and Children about romantic and intimate behaviors. A total of 24% of 11- to…

  10. Population expansion and individual age affect endoparasite richness and diversity in a recolonising large carnivore population

    PubMed Central

    Lesniak, Ines; Heckmann, Ilja; Heitlinger, Emanuel; Szentiks, Claudia A.; Nowak, Carsten; Harms, Verena; Jarausch, Anne; Reinhardt, Ilka; Kluth, Gesa; Hofer, Heribert; Krone, Oliver

    2017-01-01

    The recent recolonisation of the Central European lowland (CEL) by the grey wolf (Canis lupus) provides an excellent opportunity to study the effect of founder events on endoparasite diversity. Which role do prey and predator populations play in the re-establishment of endoparasite life cycles? Which intrinsic and extrinsic factors control individual endoparasite diversity in an expanding host population? In 53 individually known CEL wolves sampled in Germany, we revealed a community of four cestode, eight nematode, one trematode and 12 potential Sarcocystis species through molecular genetic techniques. Infections with zoonotic Echinococcus multilocularis, Trichinella britovi and T. spiralis occurred as single cases. Per capita endoparasite species richness and diversity significantly increased with population size and changed with age, whereas sex, microsatellite heterozygosity, and geographic origin had no effect. Tapeworm abundance (Taenia spp.) was significantly higher in immigrants than natives. Metacestode prevalence was slightly higher in ungulates from wolf territories than from control areas elsewhere. Even though alternative canid definitive hosts might also play a role within the investigated parasite life cycles, our findings indicate that (1) immigrated wolves increase parasite diversity in German packs, and (2) prevalence of wolf-associated parasites had declined during wolf absence and has now risen during recolonisation. PMID:28128348

  11. Population expansion and individual age affect endoparasite richness and diversity in a recolonising large carnivore population

    NASA Astrophysics Data System (ADS)

    Lesniak, Ines; Heckmann, Ilja; Heitlinger, Emanuel; Szentiks, Claudia A.; Nowak, Carsten; Harms, Verena; Jarausch, Anne; Reinhardt, Ilka; Kluth, Gesa; Hofer, Heribert; Krone, Oliver

    2017-01-01

    The recent recolonisation of the Central European lowland (CEL) by the grey wolf (Canis lupus) provides an excellent opportunity to study the effect of founder events on endoparasite diversity. Which role do prey and predator populations play in the re-establishment of endoparasite life cycles? Which intrinsic and extrinsic factors control individual endoparasite diversity in an expanding host population? In 53 individually known CEL wolves sampled in Germany, we revealed a community of four cestode, eight nematode, one trematode and 12 potential Sarcocystis species through molecular genetic techniques. Infections with zoonotic Echinococcus multilocularis, Trichinella britovi and T. spiralis occurred as single cases. Per capita endoparasite species richness and diversity significantly increased with population size and changed with age, whereas sex, microsatellite heterozygosity, and geographic origin had no effect. Tapeworm abundance (Taenia spp.) was significantly higher in immigrants than natives. Metacestode prevalence was slightly higher in ungulates from wolf territories than from control areas elsewhere. Even though alternative canid definitive hosts might also play a role within the investigated parasite life cycles, our findings indicate that (1) immigrated wolves increase parasite diversity in German packs, and (2) prevalence of wolf-associated parasites had declined during wolf absence and has now risen during recolonisation.

  12. Population expansion and individual age affect endoparasite richness and diversity in a recolonising large carnivore population.

    PubMed

    Lesniak, Ines; Heckmann, Ilja; Heitlinger, Emanuel; Szentiks, Claudia A; Nowak, Carsten; Harms, Verena; Jarausch, Anne; Reinhardt, Ilka; Kluth, Gesa; Hofer, Heribert; Krone, Oliver

    2017-01-27

    The recent recolonisation of the Central European lowland (CEL) by the grey wolf (Canis lupus) provides an excellent opportunity to study the effect of founder events on endoparasite diversity. Which role do prey and predator populations play in the re-establishment of endoparasite life cycles? Which intrinsic and extrinsic factors control individual endoparasite diversity in an expanding host population? In 53 individually known CEL wolves sampled in Germany, we revealed a community of four cestode, eight nematode, one trematode and 12 potential Sarcocystis species through molecular genetic techniques. Infections with zoonotic Echinococcus multilocularis, Trichinella britovi and T. spiralis occurred as single cases. Per capita endoparasite species richness and diversity significantly increased with population size and changed with age, whereas sex, microsatellite heterozygosity, and geographic origin had no effect. Tapeworm abundance (Taenia spp.) was significantly higher in immigrants than natives. Metacestode prevalence was slightly higher in ungulates from wolf territories than from control areas elsewhere. Even though alternative canid definitive hosts might also play a role within the investigated parasite life cycles, our findings indicate that (1) immigrated wolves increase parasite diversity in German packs, and (2) prevalence of wolf-associated parasites had declined during wolf absence and has now risen during recolonisation.

  13. Population dynamics of Empetrum hermaphroditum (Ericaceae) on a subarctic sand dune: Evidence of rapid colonization through efficient sexual reproduction.

    PubMed

    Boudreau, Stéphane; Ropars, Pascale; Harper, Karen Amanda

    2010-05-01

    The importance of sexual reproduction for clonal plant species has long been underestimated, perhaps as a consequence of the difficulty in identifying individuals, preventing the study of their population dynamics. Such is the case for Empetrum hermaphroditum, an ericaceous species, which dominates the ground vegetation of subarctic ecosystems. Despite abundant seed production, seedlings are rarely observed. Therefore, prevalent seedling recruitment on a subarctic dune system provided an opportunity to study the population dynamics and spatial pattern of the colonization phase of this species. We established a 6-ha grid on the dune systems that extended from the shoreline to the fixed dunes and mapped and measured all E. hermaphroditum individuals in the grid. Moreover, we sampled 112 individuals just outside the grid to identify any allometric relationship between the size and age of the individuals, which allowed us to reconstruct population expansion. The overall size structure suggests that the population is still expanding. In the last 50 yr, E. hermaphroditum advanced more than 200 m in the dune system. Expansion started in the 1960s simultaneously at different distances from the shoreline. Colonization did not proceed gradually from the fixed dune toward the shoreline but instead individuals established earlier in the troughs between the dunes, with an increasingly clumped spatial pattern as the population filled in with time.

  14. Sexual orientation, social capital and daily tobacco smoking: a population-based study

    PubMed Central

    2014-01-01

    Background Studies have suggested poorer health in the homosexual and bisexual groups compared to heterosexuals. Tobacco smoking, which is a health-related behavior associated with psychosocial stress, may be one explanation behind such health differences. Social capital, i.e. the generalized trust in other people and social participation/social networks which decreases the costs of social interaction, has been suggested to affect health through psychosocial pathways and through norms connected with health related behaviours, The aim of this study is to investigate the association between sexual orientation and daily tobacco smoking, taking social capital into account and analyzing the attenuation of the logit after the introduction of social participation, trust and their combination in the models. Methods In 2008 a cross-sectional public health survey was conducted in southern Sweden with a postal questionnaire with 28,198 participants aged 18–80 (55% participation rate). This study was restricted to 24,348 participants without internally missing values on all included variables. Associations between sexual orientation and tobacco smoking were analyzed with logistic regression analysis. Results Overall, 11.9% of the men and 14.8% of the women were daily tobacco smokers. Higher and almost unaltered odds ratios of daily smoking compared to heterosexuals were observed for bisexual men and women, and for homosexual men throughout the analyses. The odds ratios of daily smoking among homosexual women were not significant. Only for the “other” sexual orientation group the odds ratios of daily smoking were reduced to not significant levels among both men and women, with a corresponding 54% attenuation of the logit in the “other” group among men and 31.5% among women after the inclusion of social participation and trust. In addition, only the “other” sexual orientation group had higher odds ratios of low participation than heterosexuals. Conclusions Bisexual

  15. The evolution of the female sexual response concept: treatment implications.

    PubMed

    Damjanović, Aleksandar; Duisin, Dragana; Barisić, Jasmina

    2013-01-01

    Sexual dysfunctions have been the most prevalent group of sexual disorders and include a large number of populations of both sexes.The research of sexual behavior and treatment of women with sexual distress arises many questions related to differences in sexual response of men and women. The conceptualization of this response in modern sexology has changed over time.The objective of our paper was to present the changes and evolution of the female's sexual response concept in a summarized and integrated way, to analyze the expanded and revised definitions of the female sexual response as well as implications and recommendations of new approaches to diagnostics and treatment according to the established changes.The lack of adequate empirical basis of the female sexual response model is a critical question in the literature dealing with this issue. Some articles report that linear models demonstrate more correctly and precisely the sexual response of women with normal sexual functions in relation to women with sexual dysfunction. Modification of this model later resulted in a circular model which more adequately presented the sexual response of women with sexual function disorder than of women with normal sexual function.The nonlinear model of female sexual response constructed by Basson incorporates the value of emotional intimacy, sexual stimulus and satisfaction with the relationship. Female functioning is significantly affected by multiple psychosocial factors such as satisfaction with the relationship, self-image, earlier negative sexual experience, etc. Newly revised, expanded definitions of female sexual dysfunction try to contribute to new knowledge about a highly contextual nature of woman's sexuality so as to enhance clinical treatment of dysfunctions.The definitions emphasize the evaluation of the context of women's problematic sexual experiences.

  16. Highly recombinant VGII Cryptococcus gattii population develops clonal outbreak clusters through both sexual macroevolution and asexual microevolution.

    PubMed

    Billmyre, R Blake; Croll, Daniel; Li, Wenjun; Mieczkowski, Piotr; Carter, Dee A; Cuomo, Christina A; Kronstad, James W; Heitman, Joseph

    2014-07-29

    An outbreak of the fungal pathogen Cryptococcus gattii began in the Pacific Northwest (PNW) in the late 1990s. This outbreak consists of three clonal subpopulations: VGIIa/major, VGIIb/minor, and VGIIc/novel. Both VGIIa and VGIIc are unique to the PNW and exhibit increased virulence. In this study, we sequenced the genomes of isolates from these three groups, as well as global isolates, and analyzed a total of 53 isolates. We found that VGIIa/b/c populations show evidence of clonal expansion in the PNW. Whole-genome sequencing provided evidence that VGIIb originated in Australia, while VGIIa may have originated in South America, and these were likely independently introduced. Additionally, the VGIIa outbreak lineage may have arisen from a less virulent clade that contained a mutation in the MSH2 ortholog, but this appears to have reverted in the VGIIa outbreak strains, suggesting that a transient mutator phenotype may have contributed to adaptation and evolution of virulence in the PNW outbreak. PNW outbreak isolates share genomic islands, both between the clonal lineages and with global isolates, indicative of sexual recombination. This suggests that VGII C. gattii has undergone sexual reproduction, either bisexual or unisexual, in multiple locales contributing to the production of novel, virulent subtypes. We also found that the genomes of two basal VGII isolates from HIV(+) patients contain an introgression tract spanning three genes. Introgression substantially contributed to intra-VGII polymorphism and likely occurred through sexual reproduction with VGI. More broadly, these findings illustrate how both microevolution and sexual reproduction play central roles in the development of infectious outbreaks from avirulent or less virulent progenitors. Importance: Cryptococcus gattii is the causative agent responsible for ongoing infections in the Pacific Northwest of the United States and western Canada. The incidence of these infections increased dramatically in

  17. Changes in Sexual Behavior and Attitudes Across Generations and Gender Among a Population-Based Probability Sample From an Urbanizing Province in Thailand.

    PubMed

    Techasrivichien, Teeranee; Darawuttimaprakorn, Niphon; Punpuing, Sureeporn; Musumari, Patou Masika; Lukhele, Bhekumusa Wellington; El-Saaidi, Christina; Suguimoto, S Pilar; Feldman, Mitchell D; Ono-Kihara, Masako; Kihara, Masahiro

    2016-02-01

    Thailand has undergone rapid modernization with implications for changes in sexual norms. We investigated sexual behavior and attitudes across generations and gender among a probability sample of the general population of Nonthaburi province located near Bangkok in 2012. A tablet-based survey was performed among 2,138 men and women aged 15-59 years identified through a three-stage, stratified, probability proportional to size, clustered sampling. Descriptive statistical analysis was carried out accounting for the effects of multistage sampling. Relationship of age and gender to sexual behavior and attitudes was analyzed by bivariate analysis followed by multivariate logistic regression analysis to adjust for possible confounding. Patterns of sexual behavior and attitudes varied substantially across generations and gender. We found strong evidence for a decline in the age of sexual initiation, a shift in the type of the first sexual partner, and a greater rate of acceptance of adolescent premarital sex among younger generations. The study highlighted profound changes among young women as evidenced by a higher number of lifetime sexual partners as compared to older women. In contrast to the significant gender gap in older generations, sexual profiles of Thai young women have evolved to resemble those of young men with attitudes gradually converging to similar sexual standards. Our data suggest that higher education, being never-married, and an urban lifestyle may have been associated with these changes. Our study found that Thai sexual norms are changing dramatically. It is vital to continue monitoring such changes, considering the potential impact on the HIV/STIs epidemic and unintended pregnancies.

  18. Compulsory sexuality.

    PubMed

    Emens, Elizabeth F

    2014-02-01

    Asexuality is an emerging identity category that challenges the common assumption that everyone is defined by some type of sexual attraction. Asexuals--those who report feeling no sexual attraction to others--constitute one percent of the population, according to one prominent study. In recent years, some individuals have begun to identify as asexual and to connect around their experiences interacting with a sexual society. Asexuality has also become a protected classification under the antidiscrimination law of one state and several localities, but legal scholarship has thus far neglected the subject. This Article introduces asexuality to the legal literature as a category of analysis, an object of empirical study, and a phenomenon of medical science. It then offers a close examination of the growing community of self-identified asexuals. Asexual identity has revealing intersections with the more familiar categories of gender, sexual orientation, and disability, and inspires new models for understanding sexuality. Thinking about asexuality also sheds light on our legal system. Ours is arguably a sexual law, predicated on the assumption that sex is important. This Article uses asexuality to develop a framework for identifying the ways that law privileges sexuality. Across various fields, these interactions include legal requirements of sexual activity, special carve-outs to shield sexuality from law, legal protections from others' sexuality, and legal protections for sexual identity. Applying this framework, the Article traces several ways that our sexual law burdens, and occasionally benefits, asexuals. This Article concludes by closely examining asexuality's prospects for broader inclusion into federal, state, and local antidiscrimination laws.

  19. Assessment of sexual risk behaviors and perception of vulnerability to sexually transmitted diseases/acquired immunodeficiency syndrome in women, 1999-2012: a population based survey in a medium-sized Brazilian city.

    PubMed

    Mesenburg, Marilia Arndt; Muniz, Ludmila Correa; Silveira, Mariângela Freitas

    2014-01-01

    Sexual behavior is a key factor for susceptibility to sexually transmitted diseases. An evaluation of the sexual behavior of women at reproductive age was conducted in 1999. A replication of this study aims to evaluate the current situation and identify changes in sexual behavior, 13 years later. This is a population-based cross-sectional study, conducted with 1071 women in Pelotas, Brazil. Compared to the 1999 study, a 14% increase in early sexual debut and an 8% decrease in the non-use of condoms were observed in 2012. The proportion of women who reported anal sex doubled between these periods. There was no trend of increase or decrease in the prevalence of behaviors with distinct patterns being observed for each of them. Reduction of non-use of condoms may be an indicator of the effectiveness of campaigns to promote safe sex. However, the increased prevalence of early sexual debut and anal sex indicates the need for campaigns to continue and to expand their focus, especially among vulnerable groups.

  20. Decline and recovery of a large carnivore: environmental change and long-term trends in an endangered brown bear population.

    PubMed

    Martínez Cano, Isabel; Taboada, Fernando González; Naves, Javier; Fernández-Gil, Alberto; Wiegand, Thorsten

    2016-11-30

    Understanding what factors drive fluctuations in the abundance of endangered species is a difficult ecological problem but a major requirement to attain effective management and conservation success. The ecological traits of large mammals make this task even more complicated, calling for integrative approaches. We develop a framework combining individual-based modelling and statistical inference to assess alternative hypotheses on brown bear dynamics in the Cantabrian range (Iberian Peninsula). Models including the effect of environmental factors on mortality rates were able to reproduce three decades of variation in the number of females with cubs of the year (Fcoy), including the decline that put the population close to extinction in the mid-nineties, and the following increase in brown bear numbers. This external effect prevailed over density-dependent mechanisms (sexually selected infanticide and female reproductive suppression), with a major impact of climate driven changes in resource availability and a secondary role of changes in human pressure. Predicted changes in population structure revealed a nonlinear relationship between total abundance and the number of Fcoy, highlighting the risk of simple projections based on indirect abundance indices. This study demonstrates the advantages of integrative, mechanistic approaches and provides a widely applicable framework to improve our understanding of wildlife dynamics.

  1. Assessment of Sexual Activity and Dysfunction in Medically Underserved Women with Gynecologic Cancers

    PubMed Central

    Bradford, Andrea; Fellman, Bryan; Urbauer, Diana; Gallegos, Jessica; Meaders, Kristen; Tung, Celestine; Ramondetta, Lois

    2015-01-01

    Background Sexual dysfunction is a common long-term side effect of treatments for gynecologic cancer. Studies of sexual problems in gynecologic cancer survivors overrepresent White non-Hispanic, highly educated, and married women. Less is known about the sexual health needs of women in medically underserved populations. We therefore conducted a study to characterize sexual activity and sexual function in this population. Methods We recruited patients attending two gynecologic oncology clinics in a large public healthcare system that primarily serves uninsured and low-income patients. Participants were invited to complete a one-time survey to assess sexual function, sexual communication, sexual distress, relationship adjustment, depression, anxiety, prior help-seeking and help-seeking preferences, and reasons for sexual inactivity. Data were analyzed using descriptive statistics and multivariate models to predict sexual activity status and sexual dysfunction. Results Among 243 participants, the majority (n=160, 65.8%) were not sexually active in the past 4 weeks, most often due to lack of a partner or lack of desire for sex. Just over one-fourth of sexually active participants were identified as likely cases of sexual dysfunction. Greater endorsement of depressive symptoms predicted both sexual inactivity and sexual dysfunction in multivariate analyses. Prior help-seeking for sexual problems was uncommon; however, a significant minority of participants expressed interest in receiving care for sexual problems. Conclusions Gynecologic cancer survivors in our medically underserved population have high rates of sexual inactivity and sexual dysfunction. Future research should identify feasible strategies to address barriers to sexual health care in low-resource settings. PMID:26325527

  2. Per-capita Incidence of Sexually Transmitted Infections Increases Systematically with Urban Population Size: a cross-sectional study

    PubMed Central

    Patterson-Lomba, Oscar; Goldstein, Edward; Gómez-Liévano, Andrés; Castillo-Chavez, Carlos; Towers, Sherry

    2015-01-01

    Objectives Rampant urbanization rates across the globe demand that we improve our understanding of how infectious diseases spread in modern urban landscapes, where larger and more connected host populations enhance the thriving capacity of certain pathogens. Methods A data-driven approach is employed to study the ability of sexually transmitted diseases (STDs) to thrive in urban areas. The conduciveness of population size of urban areas and their socio-economic characteristics are used as predictors of disease incidence, using confirmed-case data on STDs in the United States as a case study. Results A superlinear relation between STD incidence and urban population size is found, even after controlling for various socio-economic aspects, suggesting that doubling the population size of a city results in an expected increase in STD incidence larger than twofold, provided that all other socio-economic aspects remain fixed. Additionally, the percentage of African Americans, income inequalities, education, and per capita income are found to have a significant impact on the incidence of each of the three STDs studied. Conclusions STDs disproportionally concentrate in larger cities. Hence, larger urban areas merit extra prevention and treatment efforts, especially in developing countries where urbanization rates are higher. PMID:25921021

  3. Testing alternative models for sexual isolation in natural populations of Littorina saxatilis: indirect support for by-product ecological speciation?

    PubMed

    Cruz, R; Carballo, M; Conde-Padín, P; Rolán-Alvarez, E

    2004-03-01

    Two ecotypes of the rough periwinkle Littorina saxatilis occur at different shore levels, showing assortative mating for size and partial reproductive isolation when they meet at the mid-shore. This system represents a putative case of incomplete speciation in sympatry. Two processes contribute to the assortative mating: morph-specific microhabitat aggregation and mate choice. The estimation of mate choice coefficients in nature and a simulation of the aggregation effects on sexual isolation were used to disentangle these processes as well as to test alternative mechanisms of mate choice. Mate choice significantly increased the frequency of within-morph pairs and significantly decreased the frequency of between-morph pairs, whereas those pairs including at least one hybrid morph mated randomly. These results allow us to reject a discriminant mate choice and support a model of evolution of sexual isolation as a side-effect of size-assortative mating in a context of divergent natural selection for size in the population. This mechanism is more compatible with a model of incomplete by-product ecological speciation, as suggested by previous evidence.

  4. Using behavior-analytic implicit tests to assess sexual interests among normal and sex-offender populations

    PubMed Central

    Roche, Bryan; O’Reilly, Anthony; Gavin, Amanda; Ruiz, Maria R.; Arancibia, Gabriela

    2012-01-01

    Background The development of implicit tests for measuring biases and behavioral predispositions is a recent development within psychology. While such tests are usually researched within a social-cognitive paradigm, behavioral researchers have also begun to view these tests as potential tests of conditioning histories, including in the sexual domain. Objective The objective of this paper is to illustrate the utility of a behavioral approach to implicit testing and means by which implicit tests can be built to the standards of behavioral psychologists. Design Research findings illustrating the short history of implicit testing within the experimental analysis of behavior are reviewed. Relevant parallel and overlapping research findings from the field of social cognition and on the Implicit Association Test are also outlined. Results New preliminary data obtained with both normal and sex offender populations are described in order to illustrate how behavior-analytically conceived implicit tests may have potential as investigative tools for assessing histories of sexual arousal conditioning and derived stimulus associations. Conclusion It is concluded that popular implicit tests are likely sensitive to conditioned and derived stimulus associations in the history of the test-taker rather than ‘unconscious cognitions’, per se. PMID:24693346

  5. Complex Population Patterns of Eunica tatila Herrich-Schäffer (Lepidoptera: Nymphalidae), with Special Emphasis on Sexual Dimorphism.

    PubMed

    Cavanzón-Medrano, L; Pozo, C; Hénaut, Y; Legal, L; Salas-Suárez, N; Machkour-M'Rabet, S

    2016-04-01

    The species Eunica tatila (Herrich-Schäffer) is present in the Neotropical region and comprises three subspecies. In Mexico, only one subspecies is reported: E. t. tatila (Herrich-Schäffer). The Yucatan Peninsula, in southeastern Mexico, is located in a transitional geographical position, between southern Florida, the West Indies and Central America. It is part of a transitional region, important for the dispersion of insects from southern Florida via Cuba and the Yucatan Peninsula. Considering the possibility of the overlapping and delimitation of described subspecies, we sampled different populations in the Yucatan Peninsula to possibly assign a subspecies name and evaluate the magnitude of sexual dimorphism. We collected 591 individuals (♀284, ♂307) in conserved areas. The study of male genitalia led to the identification of Eunica tatila tatilista (Kaye) as a subspecies; however, hypandrium structure and wing pattern analysis suggest a mix of E. t. tatila and E. t. tatilista characteristics. The analysis of sexual dimorphism provided evidence of more complex wing morphs for females, with 12 patterns instead of four as previously described. Our results demonstrate the complexity of characterizing E. tatila and suggest that the Yucatan Peninsula is a transitional zone for subspecies of some butterflies.

  6. Is female preference for large sexual ornaments due to a bias to escape predation risk?

    PubMed Central

    2012-01-01

    Background A female preference for intense sexual visual signals is widespread in animals. Although the preferences for a signal per se and for the intensity of the signal were often regarded to have the identical origin, no study has demonstrated if this is true. It was suggested that the female fiddler crabs prefer males with courtship structures because of direct benefit to escape predation. Here we tested if female preference for both components (i.e. presence and size) of the courtship structure in Uca lactea is from the sensory bias to escape predation. If both components have the identical origin, females should show the same response to different-sized courtship structures regardless of predation risk. Results First, we observed responses of mate-searching female U. lactea to courting males with full-sized, half-sized and no semidomes which were experimentally manipulated. Females had a directional preference for males with bigger semidomes within normal variation. Thereafter, we tested the effect of predation risk on the female bias in the non-courtship context. When threatened by an avian mock predator, females preferentially approached burrows with full-sized semidomes regardless of reproductive cycles (i.e. reproductive periods and non-reproductive periods). When the predator cue was absent, however, females preferred burrows with semidomes without discriminating structure size during reproductive periods but did not show any bias during non-reproductive periods. Conclusions Results indicate that selection for the size of courtship structures in U. lactea may have an origin in the function to reduce predation risk, but that the preference for males with structures may have evolved by female choice, independent of predation pressure. PMID:22413838

  7. Overcoming the dichotomy between open and isolated populations using genomic data from a large European dataset

    PubMed Central

    Anagnostou, Paolo; Dominici, Valentina; Battaggia, Cinzia; Pagani, Luca; Vilar, Miguel; Wells, R. Spencer; Pettener, Davide; Sarno, Stefania; Boattini, Alessio; Francalacci, Paolo; Colonna, Vincenza; Vona, Giuseppe; Calò, Carla; Destro Bisol, Giovanni; Tofanelli, Sergio

    2017-01-01

    Human populations are often dichotomized into “isolated” and “open” categories using cultural and/or geographical barriers to gene flow as differential criteria. Although widespread, the use of these alternative categories could obscure further heterogeneity due to inter-population differences in effective size, growth rate, and timing or amount of gene flow. We compared intra and inter-population variation measures combining novel and literature data relative to 87,818 autosomal SNPs in 14 open populations and 10 geographic and/or linguistic European isolates. Patterns of intra-population diversity were found to vary considerably more among isolates, probably due to differential levels of drift and inbreeding. The relatively large effective size estimated for some population isolates challenges the generalized view that they originate from small founding groups. Principal component scores based on measures of intra-population variation of isolated and open populations were found to be distributed along a continuum, with an area of intersection between the two groups. Patterns of inter-population diversity were even closer, as we were able to detect some differences between population groups only for a few multidimensional scaling dimensions. Therefore, different lines of evidence suggest that dichotomizing human populations into open and isolated groups fails to capture the actual relations among their genomic features. PMID:28145502

  8. Overcoming the dichotomy between open and isolated populations using genomic data from a large European dataset.

    PubMed

    Anagnostou, Paolo; Dominici, Valentina; Battaggia, Cinzia; Pagani, Luca; Vilar, Miguel; Wells, R Spencer; Pettener, Davide; Sarno, Stefania; Boattini, Alessio; Francalacci, Paolo; Colonna, Vincenza; Vona, Giuseppe; Calò, Carla; Destro Bisol, Giovanni; Tofanelli, Sergio

    2017-02-01

    Human populations are often dichotomized into "isolated" and "open" categories using cultural and/or geographical barriers to gene flow as differential criteria. Although widespread, the use of these alternative categories could obscure further heterogeneity due to inter-population differences in effective size, growth rate, and timing or amount of gene flow. We compared intra and inter-population variation measures combining novel and literature data relative to 87,818 autosomal SNPs in 14 open populations and 10 geographic and/or linguistic European isolates. Patterns of intra-population diversity were found to vary considerably more among isolates, probably due to differential levels of drift and inbreeding. The relatively large effective size estimated for some population isolates challenges the generalized view that they originate from small founding groups. Principal component scores based on measures of intra-population variation of isolated and open populations were found to be distributed along a continuum, with an area of intersection between the two groups. Patterns of inter-population diversity were even closer, as we were able to detect some differences between population groups only for a few multidimensional scaling dimensions. Therefore, different lines of evidence suggest that dichotomizing human populations into open and isolated groups fails to capture the actual relations among their genomic features.

  9. Rapid declines of large mammal populations after the collapse of the Soviet Union.

    PubMed

    Bragina, Eugenia V; Ives, A R; Pidgeon, A M; Kuemmerle, T; Baskin, L M; Gubar, Y P; Piquer-Rodríguez, M; Keuler, N S; Petrosyan, V G; Radeloff, V C

    2015-06-01

    Anecdotal evidence suggests that socioeconomic shocks strongly affect wildlife populations, but quantitative evidence is sparse. The collapse of socialism in Russia in 1991 caused a major socioeconomic shock, including a sharp increase in poverty. We analyzed population trends of 8 large mammals in Russia from 1981 to 2010 (i.e., before and after the collapse). We hypothesized that the collapse would first cause population declines, primarily due to overexploitation, and then population increases due to adaptation of wildlife to new environments following the collapse. The long-term Database of the Russian Federal Agency of Game Mammal Monitoring, consisting of up to 50,000 transects that are monitored annually, provided an exceptional data set for investigating these population trends. Three species showed strong declines in population growth rates in the decade following the collapse, while grey wolf (Canis lupus) increased by more than 150%. After 2000 some trends reversed. For example, roe deer (Capreolus spp.) abundance in 2010 was the highest of any period in our study. Likely reasons for the population declines in the 1990s include poaching and the erosion of wildlife protection enforcement. The rapid increase of the grey wolf populations is likely due to the cessation of governmental population control. In general, the widespread declines in wildlife populations after the collapse of the Soviet Union highlight the magnitude of the effects that socioeconomic shocks can have on wildlife populations and the possible need for special conservation efforts during such times.

  10. Population diversity of Puccinia graminis is sustained through sexual cycle on alternate hosts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A high degree of virulence diversity has been maintained in the population of Puccinia graminis f. sp. tritici (Pgt) in northwestern United States. Although Berberis vulgaris is present in the region and Pgt has been isolated from aecial infections on B. vulgaris, the population is too diverse to be...

  11. Structural approaches for prevention of sexually transmitted HIV in general populations: definitions and an operational approach

    PubMed Central

    Parkhurst, Justin O

    2014-01-01

    Introduction Although biomedical HIV prevention efforts have seen a number of recent promising developments, behavioural interventions have often been described as failing. However, clear lessons have been identified from past efforts, including the need to address influential social, economic and legal structures; to tailor efforts to local contexts; and to address multiple influencing factors in combination. Despite these insights, there remains a pervasive strategy to try to achieve sexual behaviour change through single, decontextualized, interventions or sets of activities. With current calls for structural approaches to HIV as part of combination HIV prevention, though, there is a unique opportunity to define a structural approach to HIV prevention as one which moves beyond these past limitations and better incorporates our knowledge of the social world and the lessons from past efforts. Discussion A range of interlinked concepts require delineation and definition within the broad concept of a structural approach to HIV. This includes distinguishing between “structural factors,” which can be seen as any number of elements (other than knowledge) which influence risk and vulnerability, and “structural drivers,” which should be reserved for situations where an empirically established relationship to a target group is known. Operationalizing structural approaches similarly can take different paths, either working to alter structural drivers or alternatively working to build individual and community resilience to infection. A “structural diagnostic approach” is further defined as the process one undertakes to develop structural intervention strategies tailored to target groups. Conclusions For three decades, the HIV prevention community has struggled to reduce the spread of HIV through sexual risk behaviours with limited success, but equally with limited engagement with the lessons that have been learned about the social realities shaping patterns of

  12. Highly active antiretroviral therapy is associated with decreased incidence of sexually transmitted diseases in a Taiwanese HIV-positive population.

    PubMed

    Cheng, Shu-Hsing; Yang, Chin-Hui; Hsueh, Yu-Mei

    2013-03-01

    There are reports of increased sexual risk behaviors in the HIV-positive population since the introduction of highly active antiretroviral therapy (HAART). Little is known about the effects of the case management (CM) program and HAART on sexually transmitted diseases (STDs) in Taiwan. HIV-positive subjects, who visited the outpatient clinics of Taoyuan General Hospital between 2007 and 2010, were enrolled. A total of 574 subjects and 14,462 person-months were reviewed. Incident STDs occurred in 104 (18.1%) subjects, and the incidence rate was 8.6 (95% confidence interval [CI], 7.1-10.5) per 100 person-years (PY). For men who have sex with men (MSM), heterosexual men and women, and injection drug users (IDU), 19.4 per 100 PY(95% CI, 15.7-24.0), 3.5 per 100 PY (95% CI, 1.4-7.3), and 1.1 per 100 PY (95% CI, 0.4-2.4) of STDs were noted, respectively; (MSM versus IDU and MSM versus heterosexual subjects, p<0.000001; heterosexual subjects versus IDU, p=0.061). Syphilis (59.6%) was the most common STD. Regular CM and no HAART (hazard ratio, 2.58; 95% CI, 1.14-5.84; p=0.02) was significantly associated with STDs in MSM. Though this retrospective study might underestimate the incidence of STDs and not draw the conclusion of causality, we concluded that the CM program and HAART are associated with lower acquisition of STDs in the Taiwanese HIV-positive population.

  13. Premating isolation is determined by larval rearing substrates in cactophilic Drosophila mojavensis. IX. Host plant and population specific epicuticular hydrocarbon expression influences mate choice and sexual selection.

    PubMed

    Havens, J A; Etges, W J

    2013-03-01

    Sexual signals in cactophilic Drosophila mojavensis include cuticular hydrocarbons (CHCs), contact pheromones that mediate female discrimination of males during courtship. CHCs, along with male courtship songs, cause premating isolation between diverged populations, and are influenced by genotype × environment interactions caused by different host cacti. CHC profiles of mated and unmated adult flies from a Baja California and a mainland Mexico population of D. mojavensis reared on two host cacti were assayed to test the hypothesis that male CHCs mediate within-population female discrimination of males. In multiple choice courtship trials, mated and unmated males differed in CHC profiles, indicating that females prefer males with particular blends of CHCs. Mated and unmated females significantly differed in CHC profiles as well. Adults in the choice trials had CHC profiles that were significantly different from those in pair-mated adults from no-choice trials revealing an influence of sexual selection. Females preferred different male CHC blends in each population, but the influence of host cactus on CHC variation was significant only in the mainland population indicating population-specific plasticity in CHCs. Different groups of CHCs mediated female choice-based sexual selection in each population suggesting that geographical and ecological divergence has the potential to promote divergence in mate communication systems.

  14. Sexual Abuse and Sexual Functioning in a Chronic Pelvic Pain Sample

    ERIC Educational Resources Information Center

    Randolph, Mary E.; Reddy, Diane M.

    2006-01-01

    Sexual abuse, particularly childhood sexual abuse, has been linked to chronic pelvic pain and to sexual dysfunction, though the sexual functioning of survivors of sexual abuse has not been studied in a chronic pain population. Sixty-three women with chronic pelvic pain completed measures of sexual function, sexual abuse, and pain. Using an index…

  15. Large-scale control site selection for population monitoring: an example assessing Sage-grouse trends

    USGS Publications Warehouse

    Fedy, Bradley C.; O'Donnell, Michael; Bowen, Zachary H.

    2015-01-01

    Human impacts on wildlife populations are widespread and prolific and understanding wildlife responses to human impacts is a fundamental component of wildlife management. The first step to understanding wildlife responses is the documentation of changes in wildlife population parameters, such as population size. Meaningful assessment of population changes in potentially impacted sites requires the establishment of monitoring at similar, nonimpacted, control sites. However, it is often difficult to identify appropriate control sites in wildlife populations. We demonstrated use of Geographic Information System (GIS) data across large spatial scales to select biologically relevant control sites for population monitoring. Greater sage-grouse (Centrocercus urophasianus; hearafter, sage-grouse) are negatively affected by energy development, and monitoring of sage-grouse population within energy development areas is necessary to detect population-level responses. Weused population data (1995–2012) from an energy development area in Wyoming, USA, the Atlantic Rim Project Area (ARPA), and GIS data to identify control sites that were not impacted by energy development for population monitoring. Control sites were surrounded by similar habitat and were within similar climate areas to the ARPA. We developed nonlinear trend models for both the ARPA and control sites and compared long-term trends from the 2 areas. We found little difference between the ARPA and control sites trends over time. This research demonstrated an approach for control site selection across large landscapes and can be used as a template for similar impact-monitoring studies. It is important to note that identification of changes in population parameters between control and treatment sites is only the first step in understanding the mechanisms that underlie those changes. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  16. Simulating natural conditions in the laboratory: a re-examination of sexual isolation between sympatric and allopatric populations of Drosophila pseudoobscura and D. persimilis.

    PubMed

    Noor, Mohamed A F; Ortíz-Barrientos, Daniel

    2006-03-01

    Simulating natural conditions in the laboratory poses one of the most significant challenges to behavioral studies. Some authors have argued that laboratory "choice" experiments reflect mate choice in nature more accurately than "no-choice" experiments. A recent choice experiment study questioned the conclusions of several earlier studies by failing to detect a published difference in sexual isolation between populations of Drosophila pseudoobscura, and suggested their result was more robust because of the more realistic design. Here, we re-examine the methods and analyses of this recent study, and we find there was indeed a difference in sexual isolation between populations of D. pseudoobscura. We also conduct a more rigorously controlled choice experiment and, in agreement with previous studies, note that D. pseudoobscura females from populations sympatric to their sibling species, D. persimilis, exhibit greater sexual isolation than those from allopatric populations. Our results confirm the existence of a geographic pattern in sexual isolation in D. pseudoobscura, and we discuss differences in experimental designs in light of the biology of this species.

  17. Challenges of cardiac image analysis in large-scale population-based studies.

    PubMed

    Medrano-Gracia, Pau; Cowan, Brett R; Suinesiaputra, Avan; Young, Alistair A

    2015-03-01

    Large-scale population-based imaging studies of preclinical and clinical heart disease are becoming possible due to the advent of standardized robust non-invasive imaging methods and infrastructure for big data analysis. This gives an exciting opportunity to gain new information about the development and progression of heart disease across population groups. However, the large amount of image data and prohibitive time required for image analysis present challenges for obtaining useful derived data from the images. Automated analysis tools for cardiac image analysis are only now becoming available. This paper reviews the challenges and possible solutions to the analysis of big imaging data in population studies. We also highlight the potential of recent large epidemiological studies using cardiac imaging to discover new knowledge on heart health and well-being.

  18. Abortion research: attitudes, sexual behavior, and problems in a community college population.

    PubMed

    Bryan, J W; Freed, F W

    1993-02-01

    150 (80 females and 70 males) community college students were surveyed regarding their attitudes toward abortion, their sexual behavior, and their problems. The profile of the students was Caucasian (95%), young (18-24 years = 87%), single (87%), middle and lower middle class, and Catholic (70%). 82% supported abortion choice, 86% had engaged in premarital sex, 70% used contraception, and 26% had premarital pregnancies. The hard reasons for abortion (rape, the woman's life, is endangered, and the fetus is defective) received high support. The soft reasons (the family cannot afford more children or the woman does not want to marry the man) received lower support. The students were divided into 3 groups of 50 students based on the number of abortion reasons they supported out of 43 reasons. The low-group that accepted 0-10 reasons was called anti-abortion. 50% of them still believed a woman has a right to an abortion vs. 97% of the pro-abortion students. The students reported many problems in their families: alcoholic home (39%), loss of a parent through death, divorce, or separation (33%), victims of severe corporal punishment (31%), one or more family members physically abused (20%), and deprived of parental affection while growing up (20%). When the anti-abortion females (N=30) were compared with the pro-abortion females (N=50), they reported significantly (p.01) more hospitalization, a greater number of physical handicaps, and more shyness (p.1). When the anti-abortion males (N=20) were compared with the pro-abortion males (N=50), they reported significantly more obesity and agoraphobia (p.05) and more convictions for a crime (p.1). Comparison of women who had abortion (N=13) with the women who had their baby (N=8) indicated that the latter reported significantly (p.01) more battering by their boyfriend or husband, significantly (p.05) more battering in their family of origin and childhood sexual abuse, and a greater tendency (p.1) to have been raped.

  19. Let’s Get Physical: Sexual Orientation Disparities in Physical Activity, Sports Involvement, and Obesity Among a Population-Based Sample of Adolescents

    PubMed Central

    Poteat, V. Paul

    2015-01-01

    Objectives. We examined sexual orientation disparities in physical activity, sports involvement, and obesity among a population-based adolescent sample. Methods. We analyzed data from the 2012 Dane County Youth Assessment for 13 933 students in grades 9 through 12 in 22 Wisconsin high schools. We conducted logistic regressions to examine sexual orientation disparities in physical activity, sports involvement, and body mass index among male and female adolescents. Results. When we accounted for several covariates, compared with heterosexual females, sexual minority females were less likely to participate in team sports (adjusted odds ratio [AOR] = 0.44; 95% confidence interval [CI] = 0.37, 0.53) and more likely to be overweight (AOR = 1.28; 95% CI = 1.02, 1.62) or obese (AOR = 1.88; 95% CI = 1.43, 2.48). Sexual minority males were less likely than heterosexual males to be physically active (AOR = 0.62; 95% CI = 0.46, 0.83) or to participate in team sports (AOR = 0.26; 95% CI = 0.20, 0.32), but the 2 groups did not differ in their risk of obesity. Conclusions. Sexual orientation health disparities in physical activity and obesity are evident during adolescence. Culturally affirming research, interventions, and policies are needed for sexual minority youths. PMID:26180946

  20. Population structure and the evolution of sexual size dimorphism and sex ratios in an insular population of Florida box turtles (Terrapene carolina bauri)

    USGS Publications Warehouse

    Dodd, C.K.

    1997-01-01

    Hypotheses in the chelonian literature suggest that in species with sexual size dimorphism, the smaller sex will mature at a smaller size and a younger age than the larger sex, sex ratios should be biased in favor of the earlier maturing sex, and deviations from a 1:1 sex ratio result from maturation of the smaller sex at a younger age. I tested these hypotheses using data collected from 1991 to 1995 on an insular (Egmont Key) population of Florida box turtles, Terrapene carolina bauri. Contrary to predictions, the earlier maturing sex (males) grew to larger sizes than the late maturing sex. Males were significantly larger than females in mean carapace length but not mean body mass. Sex ratios were not balanced, favoring the earlier maturing sex (1.6 males:1 female), but the sex-ratio imbalance did not result from faster maturation of the smaller sex. The imbalance in the sex ratio in Egmont Key's box turtles is not the result of sampling biases; it may result from nest placement. Size-class structure and sex ratios can provide valuable insights into the status and trends of populations of long-lived turtles.

  1. Minireview: Hormones and human sexual orientation.

    PubMed

    Balthazart, Jacques

    2011-08-01

    Many people believe that sexual orientation (homosexuality vs. heterosexuality) is determined by education and social constraints. There are, however, a large number of studies indicating that prenatal factors have an important influence on this critical feature of human sexuality. Sexual orientation is a sexually differentiated trait (over 90% of men are attracted to women and vice versa). In animals and men, many sexually differentiated characteristics are organized during early life by sex steroids, and one can wonder whether the same mechanism also affects human sexual orientation. Two types of evidence support this notion. First, multiple sexually differentiated behavioral, physiological, or even morphological traits are significantly different in homosexual and heterosexual populations. Because some of these traits are known to be organized by prenatal steroids, including testosterone, these differences suggest that homosexual subjects were, on average, exposed to atypical endocrine conditions during development. Second, clinical conditions associated with significant endocrine changes during embryonic life often result in an increased incidence of homosexuality. It seems therefore that the prenatal endocrine environment has a significant influence on human sexual orientation but a large fraction of the variance in this behavioral characteristic remains unexplained to date. Genetic differences affecting behavior either in a direct manner or by changing embryonic hormone secretion or action may also be involved. How these biological prenatal factors interact with postnatal social factors to determine life-long sexual orientation remains to be determined.

  2. Minireview: Hormones and Human Sexual Orientation

    PubMed Central

    2011-01-01

    Many people believe that sexual orientation (homosexuality vs. heterosexuality) is determined by education and social constraints. There are, however, a large number of studies indicating that prenatal factors have an important influence on this critical feature of human sexuality. Sexual orientation is a sexually differentiated trait (over 90% of men are attracted to women and vice versa). In animals and men, many sexually differentiated characteristics are organized during early life by sex steroids, and one can wonder whether the same mechanism also affects human sexual orientation. Two types of evidence support this notion. First, multiple sexually differentiated behavioral, physiological, or even morphological traits are significantly different in homosexual and heterosexual populations. Because some of these traits are known to be organized by prenatal steroids, including testosterone, these differences suggest that homosexual subjects were, on average, exposed to atypical endocrine conditions during development. Second, clinical conditions associated with significant endocrine changes during embryonic life often result in an increased incidence of homosexuality. It seems therefore that the prenatal endocrine environment has a significant influence on human sexual orientation but a large fraction of the variance in this behavioral characteristic remains unexplained to date. Genetic differences affecting behavior either in a direct manner or by changing embryonic hormone secretion or action may also be involved. How these biological prenatal factors interact with postnatal social factors to determine life-long sexual orientation remains to be determined. PMID:21693676

  3. Quantitative digital and palmar dermatoglyphics: sexual dimorphism in the Chuvashian population of Russia.

    PubMed

    Karmakar, B; Yakovenko, K; Kobyliansky, E

    2008-01-01

    With the aim of determining sex dimorphism among the Chuvashian population of Russia, digital and palmar dermatoglyphics of 547 individuals (293 males, 254 females) were analyzed. The sex differences for PII, TRC, and AFRC are similar to Indian and Jewish populations. Correlation coefficients between individual finger ridge counts are a little lower than in Jews but are almost equal to Indian populations. The Mantel test of matrix correlation between sexes for 22 traits shows a very good similarity. However, sex differences of palmar traits display different levels when compared with other human populations. In light of this, our evidence indicates the possible role of environmental (prenatal) factors in the realization of dermatoglyphic sex differences. The development of palmar dermatoglyphics has had a relatively longer growth period compared with fingers [Cummins, H., 1929. The topographic history of the volar pads (walking pads, tast ballen) in the human embryo. Embryol. 20, 103-126]. The palmar dermatoglyphic pattern of affinities therefore corresponds better than fingers to the ethno historical background of the populations, ascertained by numerous studies.

  4. Religious Climate and Health Risk Behaviors in Sexual Minority Youths: A Population-Based Study

    PubMed Central

    Pachankis, John E.; Wolff, Joshua

    2012-01-01

    Objectives. We examined whether the health risk behaviors of lesbian, gay, and bisexual (LGB) youths are determined in part by the religious composition of the communities in which they live. Methods. Data were collected from 31 852 high school students, including 1413 LGB students, who participated in the Oregon Healthy Teens survey in 2006 through 2008. Supportive religious climate was operationalized according to the proportion of individuals (of the total number of religious adherents) who adhere to a religion supporting homosexuality. Comprehensive data on religious climate were derived from 85 denominational groups in 34 Oregon counties. Results. Among LGB youths, living in a county with a religious climate that was supportive of homosexuality was associated with significantly fewer alcohol abuse symptoms (odds ratio [OR] = 0.58; 95% confidence interval [CI] = 0.40, 0.85) and fewer sexual partners (OR = 0.77; 95% CI = 0.60, 0.99). The effect of religious climate on health behaviors was stronger among LGB than heterosexual youths. Results remained robust after adjustment for multiple confounding factors. Conclusions. The religious climate surrounding LGB youths may serve as a determinant of their health risk behaviors. PMID:22397347

  5. Sexually Transmitted Diseases as a Risk for Acquiring HIV Infection among the Population of Men Who Have Sex with Men--A Case-Control Study.

    PubMed

    Lakoseljac, Danijela; Gjenero-Margan, Ira; Kolarić, Branko; Rukavina, Tomislav; Blazić, Tatjana Nemeth

    2015-09-01

    At the beginning of the 1980-ies, HIV infection and AIDS were described for the first time, this among the population of men who have sex with other men. Nearly thirty years later, the MSM population is still a population under heightened risk for acquiring HIV infection and other sexually transmitted diseases. This study investigates sexually transmitted diseases as a risk for HIV infection. A total of 296 men who have sex with men (MSM) were included in this case control study. Differences among the frequencies of sexually transmitted diseases among the MSM of HIV positive and HIV negative status were tested. The history of HIV positive more often states falling ill with sexually transmitted diseases than this was the case before they became HIV positive, unlike those MSM who are not HIV infected (45.9%:11.1% that is OR 6.79, 95% CI 3.49-13.19). Hepatitis B infection is more frequent in HIV positive MSM (11.5%:1.9%; OR 6.58, 95% CI 1.86-23.3). The frequency of gonorrhea in case history of HIV positive MSM is significantly higher than in the HIV negative group (11.5%:3.8%, OR 3.24, 95% CI 1.13-9.34). In the group of HIV positive MSM, unlike the HIV negative group, syphilis (14.8:1.0%, OR 1774, 95% CI 3.43-122.87) and genital herpes (8.2%:0.5%, OR 18.39, 95% CI 2.03-424.7) are more frequent. The results of this study will be used in future preventive activities focused on the population of MSM, as a population under particular risk for acquiring sexually transmitted infections.

  6. Salivary Testosterone Levels and Health Status in Men and Women in the British General Population: Findings from the Third National Survey of Sexual Attitudes and Lifestyles (Natsal-3)

    PubMed Central

    Macdowall, W.; Copas, A. J.; Tanton, C.; Keevil, B. G.; Lee, D. M.; Mitchell, K. R.; Field, N.; Sonnenberg, P.; Bancroft, J.; Mercer, C. H.; Wallace, A. M.; Johnson, A. M.; Wellings, K.; Wu, F. C. W.

    2016-01-01

    Context: Salivary T (Sal-T) measurement by liquid chromatography–tandem mass spectroscopy resents the opportunity to examine health correlates of Sal-T in a large-scale population survey. Objective: This study sought to examine associations between Sal-T and health-related factors in men and women age 18–74 years. Design and Setting: Morning saliva samples were obtained from participants in a cross-sectional probability-sample survey of the general British population (Natsal-3). Self-reported health and lifestyle questions were administered as part of a wider sexual health interview. Participants: Study participants included 1599 men and 2123 women. Methods: Sal-T was measured using liquid chromatography–tandem mass spectroscopy. Linear regression was used to examine associations between health factors and mean Sal-T. Results: In men, mean Sal-T was associated with a range of health factors after age adjustment, and showed a strong independent negative association with body mass index (BMI) in multivariable analysis. Men reporting cardiovascular disease or currently taking medication for depression had lower age-adjusted Sal-T, although there was no association with cardiovascular disease after adjustment for BMI. The decline in Sal-T with increasing age remained after adjustment for health-related factors. In women, Sal-T declined with increasing age; however, there were no age-independent associations with health-related factors or specific heath conditions with the exception of higher Sal-T in smokers. Conclusions: Sal-T levels were associated, independently of age, with a range of self-reported health markers, particularly BMI, in men but not women. The findings support the view that there is an age-related decline in Sal-T in men and women, which cannot be explained by an increase in ill health. Our results demonstrate the potential of Sal-T as a convenient measure of tissue androgen exposure for population research. PMID:27552539

  7. Population structure of a large blue butterfly and its specialist parasitoid in a fragmented landscape.

    PubMed

    Anton, Christian; Zeisset, Inga; Musche, Martin; Durka, Walter; Boomsma, Jacobus J; Settele, Josef

    2007-09-01

    Habitat fragmentation may interrupt trophic interactions if herbivores and their specific parasitoids respond differently to decreasing connectivity of populations. Theoretical models predict that species at higher trophic levels are more negatively affected by isolation than lower trophic level species. By combining ecological data with genetic information from microsatellite markers we tested this hypothesis on the butterfly Maculinea nausithous and its specialist hymenopteran parasitoid Neotypus melanocephalus. We assessed the susceptibility of both species to habitat fragmentation by measuring population density, rate of parasitism, overall genetic differentiation (theta(ST)) and allelic richness in a large metapopulation. We also simulated the dynamics of genetic differentiation among local populations to asses the relative effects of migration rate, population size, and haplodiploid (parasitoid) and diploid (host) inheritance on metapopulation persistence. We show that parasitism by N. melanocephalus is less frequent at larger distances to the nearest neighbouring population of M. nausithous hosts, but that host density itself is not affected by isolation. Allelic richness was independent of isolation, but the mean genetic differentiation among local parasitoid populations increased with the distance between these populations. Overall, genetic differentiation in the parasitoid wasp was much greater than in the butterfly host and our simulations indicate that this difference is due to a combination of haplodiploidy and small local population sizes. Our results thus support the hypothesis that Neotypus parasitoid wasps are more sensitive to habitat fragmentation than their Maculinea butterfly hosts.

  8. Effects of genotoxicity and its consequences at the population level in sexual and asexual Artemia assessed by analysis of inter-simple sequence repeats (ISSR).

    PubMed

    Sukumaran, Sandhya; Grant, Alastair

    2013-09-18

    There is considerable evidence that genetic damage in organisms occurs in the environment as a result of exposure to genotoxins and ionising radiation, but we have limited understanding of the extent to which this results in adverse consequences at a population level. We used inter-simple sequence repeat (ISSR) markers to quantify genotoxic effects of the mutagen ethylmethane sulfonate (EMS) on a sexual (Artemia franciscana) and an asexual (Artemia parthenogenetica) species of brine shrimp. The method provides information similar to that obtained with assessment of RAPD (random amplification of polymorphic DNA) but is more robust. Genetic damage was transmitted to the F1 generation in both Artemia species, but the sexual species showed a greater degree of recovery, as shown by higher values of genomic template stability. There was a strong correlation between DNA damage and effects on individual fitness parameters: size, survival, reproduction and population growth. These effects persisted into the F2 generation in A. parthenogenetica, but in the sexual A. franciscana only effects on fecundity continued beyond the exposed generation, even though there were substantial alterations in ISSR patterns in the F1 generation. Genetic biomarkers can thus be indicative of effects at the population level, but sexually reproducing species have a considerable assimilative capacity for the effects of genotoxins.

  9. Sexual dimorphism in the Turkmenian population in two types of dermatoglyphic traits: discriminant analysis.

    PubMed

    Karmakar, Bibha; Kobyliansky, Eugene

    2009-12-01

    The aim of this study is to compare the pattern of sex differences between two different sets of dermatoglyphic traits (22 quantitative and 42 indices of diversity and asymmetry). Finger and palmar prints of Turkmenian population (547 individuals) were used for Multivariate analyses includes Cluster, Discriminant and Mantel test of matrix correlations. All variables (two groups) scattered into a number of small clusters those are markedly similar between males and females. These results were confirmed by Discriminant analysis--the two groups of variables are almost similar, the percentages of correctly classified individuals are 64.14% (22 traits) and 65.45% (42 traits); and Mantel statistics--the Z values are within the level of non-significance, very good similarities in 22 (0.95) and good similarities in 42 (0.87) traits. Sex dimorphism is similar between two categories of dermatoglyphic variables may be used for sex-discrimination in different populations.

  10. HIV populations are large and accumulate high genetic diversity in a nonlinear fashion.

    PubMed

    Maldarelli, Frank; Kearney, Mary; Palmer, Sarah; Stephens, Robert; Mican, JoAnn; Polis, Michael A; Davey, Richard T; Kovacs, Joseph; Shao, Wei; Rock-Kress, Diane; Metcalf, Julia A; Rehm, Catherine; Greer, Sarah E; Lucey, Daniel L; Danley, Kristen; Alter, Harvey; Mellors, John W; Coffin, John M

    2013-09-01

    HIV infection is characterized by rapid and error-prone viral replication resulting in genetically diverse virus populations. The rate of accumulation of diversity and the mechanisms involved are under intense study to provide useful information to understand immune evasion and the development of drug resistance. To characterize the development of viral diversity after infection, we carried out an in-depth analysis of single genome sequences of HIV pro-pol to assess diversity and divergence and to estimate replicating population sizes in a group of treatment-naive HIV-infected individuals sampled at single (n = 22) or multiple, longitudinal (n = 11) time points. Analysis of single genome sequences revealed nonlinear accumulation of sequence diversity during the course of infection. Diversity accumulated in recently infected individuals at rates 30-fold higher than in patients with chronic infection. Accumulation of synonymous changes accounted for most of the diversity during chronic infection. Accumulation of diversity resulted in population shifts, but the rates of change were low relative to estimated replication cycle times, consistent with relatively large population sizes. Analysis of changes in allele frequencies revealed effective population sizes that are substantially higher than previous estimates of approximately 1,000 infectious particles/infected individual. Taken together, these observations indicate that HIV populations are large, diverse, and slow to change in chronic infection and that the emergence of new mutations, including drug resistance mutations, is governed by both selection forces and drift.

  11. Genetic population structure and relatedness in the narrow-striped mongoose (Mungotictis decemlineata), a social Malagasy carnivore with sexual segregation.

    PubMed

    Schneider, Tilman C; Kappeler, Peter M; Pozzi, Luca

    2016-05-05

    Information on the genetic structure of animal populations can allow inferences about mechanisms shaping their social organization, dispersal, and mating system. The mongooses (Herpestidae) include some of the best-studied mammalian systems in this respect, but much less is known about their closest relatives, the Malagasy carnivores (Eupleridae), even though some of them exhibit unusual association patterns. We investigated the genetic structure of the Malagasy narrow-striped mongoose (Mungotictis decemlineata), a small forest-dwelling gregarious carnivore exhibiting sexual segregation. Based on mtDNA and microsatellite analyses, we determined population-wide haplotype structure and sex-specific and within-group relatedness. Furthermore, we analyzed parentage and sibship relationships and the level of reproductive skew. We found a matrilinear population structure, with several neighboring female units sharing identical haplotypes. Within-group female relatedness was significantly higher than expected by chance in the majority of units. Haplotype diversity of males was significantly higher than in females, indicating male-biased dispersal. Relatedness within the majority of male associations did not differ from random, not proving any kin-directed benefits of male sociality in this case. We found indications for a mildly promiscuous mating system without monopolization of females by males, and low levels of reproductive skew in both sexes based on parentages of emergent young. Low relatedness within breeding pairs confirmed immigration by males and suggested similarities with patterns in social mongooses, providing a starting point for further investigations of mate choice and female control of reproduction and the connected behavioral mechanisms. Our study contributes to the understanding of the determinants of male sociality in carnivores as well as the mechanisms of female competition in species with small social units.

  12. Human Papillomavirus Infection in a Male Population Attending a Sexually Transmitted Infection Service

    PubMed Central

    Álvarez-Argüelles, Marta Elena; Melón, Santiago; Junquera, Maria Luisa; Boga, Jose Antonio; Villa, Laura; Pérez-Castro, Sonia; de Oña, María

    2013-01-01

    Objective Human Papillomavirus (HPV) infection in men may produce cancer and other major disorders. Men play an important role in the transmission of the virus and act as a reservoir. The aim of this study was to determine the HPV-genotypes and their prevalence in a group of men attending a Sexually Transmitted Infection service. Patients and Samples Between July 2002 and June 2011, 1392 balanopreputial, 435 urethral, 123 anal, and 67 condyloma lesions from 1551 men with a mean age of 35.8±11.3 years old (range: 17–87) were collected for HPV-DNA testing. Methods A fragment of the L1-gene and a fragment of the E6/E7-genes were amplified by PCR. Positive samples were typed by hybridization. Results The HPV genome was detected in 36.9% (486/1318) balanopreputial and in 24.9% (101/405) urethral (p<0.0001) swabs from 38.1% (538) of 1469 men. Co-infections were present in 5.4% (80/1469) of cases. HPV was found in 43.9% (373/850) of men younger than 35 vs. 31.7% (187/589) of men aged >35. HPV was found in 59.4% (104) of 165 men with lesions (macroscopic or positive peniscopy), and in 22.8% (61/267) without clinical alterations. HPV was also detected in 71.4% (40/56) men with condylomata and in 58.7% (64/109) of men with positive peniscopy. Conclusions HPV prevalence in men was high and decreased with age. HPV was found more frequently in balanopreputial than in urethral swabs. There was a low rate of co-infections. Low-risk HPV vaccine genotypes were the most recurrent especially in younger. Although HPV has been associated with clinical alterations, it was also found in men without any clinical presentation. Inclusion of men in the national HPV vaccination program may reduce their burden of HPV-related disease and reduce transmission of the virus to non-vaccinated women. PMID:23372715

  13. A New Argument against an Intervening Stellar Population toward the Large Magellanic Cloud

    NASA Astrophysics Data System (ADS)

    Gould, Andrew

    1999-11-01

    Zaritsky & Lin have claimed detection of an intervening population of stars toward the Large Magellanic Cloud (LMC), which, they believe, could account for a substantial fraction of the observed microlensing events. I show that the observed timescales of these events imply that if such an intervening population were composed of ordinary stars that gave rise to a significant fraction of the microlensing events, then the population could not be associated with the LMC. I present two independent statistical arguments which together essentially rule out such a chance alignment of unassociated structures. On the other hand, if the intervening structure is associated with the LMC, I show that of order half the mass in this structure is in substellar objects, which would make it unlike any known stellar population.

  14. [Population aspects of sexual dimorphism in guild of the Mustelidae: Mustela lutreola, Neovison vison, Mustela putorius, Martes martes as an example].

    PubMed

    Korablev, M P; Korablev, N P; Korablev, P N

    2013-01-01

    Size sexual dimorphism was investigated on 695 skulls of four Mustelidae species. By extent of increasing of differences between sexes the species are placed in following order: European pine marten (Martes martes), European mink (Mustela lutreola), American mink (Neovison vison), and European polecat (Mustela putorius). Extent of the dimorphism characterizes ecological plasticity of the species and is population characteristic. It is shown that M. martes takes specific and relatively narrow ecological niche of forest ecosystems, entering into weak competitive relationships with smaller Mustelidae species. The level of sexual dimorphism of M. lutreola, N. vison and M. putorius reflects intensity of its interspecific relationships within study area. High level of sexual dimorphism of M. putorius is determined by further divergence of ecological niches of males and females, and also appears to be compensatory mechanism reducing consequences of hardened environmental requirements.

  15. Documentation of sexual partner gender is low in electronic health records: observations, predictors, and recommendations to improve population health management in primary care.

    PubMed

    Nguyen, Giang T; Yehia, Baligh R

    2015-06-01

    The 2011 Institute of Medicine report on LGBT health recommended that sexual orientation and gender identity (SO/GI) be documented in electronic health records (EHRs). Most EHRs cannot document all aspects of SO/GI, but some can record gender of sexual partners. This study sought to determine the proportion of patients who have the gender of sexual partners recorded in the EHR and to identify factors associated with documentation. A retrospective analysis was done of EHR data for 40 family medicine (FM) and general internal medicine (IM) practices, comprising 170,570 adult patients seen in 2012. The primary outcome was EHR documentation of sexual partner gender. Multivariate logistic regression assessed the impact of patient, provider, and practice factors on documentation. In all, 76,767 patients (45%) had the gender of sexual partners recorded, 4.3% of whom had same-gender partners (3.5% of females, 5.6% of males). Likelihood of documentation was independently higher for women; blacks; those with a preventive visit; those with a physician assistant, nurse practitioner, or resident primary care provider (vs. attending); those at urban practices; those at smaller practices; and those at a residency FM practice. Older age and Medicare insurance were associated with lower documentation. Sexual partner gender documentation is important to identify patients for targeted prevention and support, and holds great potential for population health management, yet documentation in the EHR currently is low. Primary care practices should routinely record the gender of sexual partners, and additional work is needed to identify best practices for collecting and using SO/GI data in this setting.

  16. HIV Risk Behaviors in the U.S. Transgender Population: Prevalence and Predictors in a Large Internet Sample

    PubMed Central

    Feldman, Jamie; Romine, Rebecca Swinburne; Bockting, Walter O.

    2014-01-01

    To study the influence of gender on HIV risk, a sample of the U.S. transgender population (N = 1,229) was recruited via the Internet. HIV risk and prevalence were lower than reported in prior studies of localized, urban samples, but higher than the overall U.S. population. Findings suggest that gender nonconformity alone does not itself result in markedly higher HIV risk. Sex with nontransgender men emerged as the strongest independent predictor of unsafe sex for both male-to-female (MtF) and female-to-male (FtM) participants. These sexual relationships constitute a process that may either affirm or problematize gender identity and sexual orientation, with different emphases for MtFs and FtMs, respectively. PMID:25022491

  17. HIV risk behaviors in the U.S. transgender population: prevalence and predictors in a large internet sample.

    PubMed

    Feldman, Jamie; Romine, Rebecca Swinburne; Bockting, Walter O

    2014-01-01

    To study the influence of gender on HIV risk, a sample of the U.S. transgender population (N = 1,229) was recruited via the Internet. HIV risk and prevalence were lower than reported in prior studies of localized, urban samples but higher than the overall U.S. population. Findings suggest that gender nonconformity alone does not itself result in markedly higher HIV risk. Sex with nontransgender men emerged as the strongest independent predictor of unsafe sex for both male-to-female (MtF) and female-to-male (FtM) participants. These sexual relationships constitute a process that may either affirm or problematize gender identity and sexual orientation, with different emphases for MtFs and FtMs, respectively.

  18. 4P: fast computing of population genetics statistics from large DNA polymorphism panels

    PubMed Central

    Benazzo, Andrea; Panziera, Alex; Bertorelle, Giorgio

    2015-01-01

    Massive DNA sequencing has significantly increased the amount of data available for population genetics and molecular ecology studies. However, the parallel computation of simple statistics within and between populations from large panels of polymorphic sites is not yet available, making the exploratory analyses of a set or subset of data a very laborious task. Here, we present 4P (parallel processing of polymorphism panels), a stand-alone software program for the rapid computation of genetic variation statistics (including the joint frequency spectrum) from millions of DNA variants in multiple individuals and multiple populations. It handles a standard input file format commonly used to store DNA variation from empirical or simulation experiments. The computational performance of 4P was evaluated using large SNP (single nucleotide polymorphism) datasets from human genomes or obtained by simulations. 4P was faster or much faster than other comparable programs, and the impact of parallel computing using multicore computers or servers was evident. 4P is a useful tool for biologists who need a simple and rapid computer program to run exploratory population genetics analyses in large panels of genomic data. It is also particularly suitable to analyze multiple data sets produced in simulation studies. Unix, Windows, and MacOs versions are provided, as well as the source code for easier pipeline implementations. PMID:25628874

  19. Large population solution of the stochastic Luria-Delbruck evolution model.

    PubMed

    Kessler, David A; Levine, Herbert

    2013-07-16

    Luria and Delbrück introduced a very useful and subsequently widely adopted framework for quantitatively understanding the emergence of new cellular lineages. Here, we provide an analytical treatment of the fully stochastic version of the model, enabled by the fact that population sizes at the time of measurement are invariably very large and mutation rates are low. We show that the Lea-Coulson generating function describes the "inner solution," where the number of mutants is much smaller than the total population. We find that the corresponding distribution function interpolates between a monotonic decrease at relatively small populations, (compared with the inverse of the mutation probability), whereas it goes over to a Lévy α-stable distribution in the very large population limit. The moments are completely determined by the outer solution, and so are devoid of practical significance. The key to our solution is focusing on the fixed population size ensemble, which we show is very different from the fixed time ensemble due to the extreme variability in the evolutionary process.

  20. Managing Natural and Reintroduced Rare Plant Populations within a Large Government Reservation

    SciTech Connect

    Carlsen, T M; Paterson, L E; Alfaro, T M

    2009-07-15

    California is home to many large government reservations that have been in existence for decades. Many of these reservations were formed to support various Department of Defense and Department of Energy national defense activities. Often, only a very small percentage of the reservation is actively used for programmatic activities, resulting in large areas of intact habitat. In some cases, this has benefited rare plant populations, as surrounding lands have been developed for residential or industrial use. However, land management activities such as the suppression or active use of fire and other disturbance (such as fire trail grading) can also work to either the detriment or benefit of rare plant populations at these sites. A management regime that is beneficial to the rare plant populations of interest and is at best consistent with existing site programmatic activities, and at a minimum does not impact such activities, has the best potential for a positive outcome. As a result, some species may be 'difficult' while others may be 'easy' to manage in this context, depending on how closely the species biological requirements match the programmatic activities on the reservation. To illustrate, we compare and contrast two rare annual plant species found at Lawrence Livermore National Laboratory's Site 300. Although several populations of Amsinckia grandiflora have been restored on the site, and all populations are intensively managed, this species continues to decline. In contrast, Blepharizonia plumosa appears to take advantage of the annual controlled burns conducted on the site, and is thriving.

  1. Disease-mediated inbreeding depression in a large, open population of cooperative crows

    PubMed Central

    Townsend, Andrea K.; Clark, Anne B.; McGowan, Kevin J.; Buckles, Elizabeth L.; Miller, Andrew D.; Lovette, Irby J.

    2009-01-01

    Disease-mediated inbreeding depression is a potential cost of living in groups with kin, but its general magnitude in wild populations is unclear. We examined the relationships between inbreeding, survival and disease for 312 offspring, produced by 35 parental pairs, in a large, open population of cooperatively breeding American crows (Corvus brachyrhynchos). Genetic analyses of parentage, parental relatedness coefficients and pedigree information suggested that 23 per cent of parental dyads were first- or second-order kin. Heterozygosity–heterozygosity correlations suggested that a microsatellite-based index of individual heterozygosity predicted individual genome-wide heterozygosity in this population. After excluding birds that died traumatically, survival probability was lower for relatively inbred birds during the 2–50 months after banding: the hazard rate for the most inbred birds was 170 per cent higher than that for the least inbred birds across the range of inbreeding index values. Birds that died with disease symptoms had higher inbreeding indices than birds with other fates. Our results suggest that avoidance of close inbreeding and the absence of inbreeding depression in large, open populations should not be assumed in taxa with kin-based social systems, and that microsatellite-based indices of individual heterozygosity can be an appropriate tool for examining the inbreeding depression in populations where incest and close inbreeding occur. PMID:19324784

  2. Models of population-based analyses for data collected from large extended families.

    PubMed

    Wang, Wenyu; Lee, Elisa T; Howard, Barbara V; Fabsitz, Richard R; Devereux, Richard B; MacCluer, Jean W; Laston, Sandra; Comuzzie, Anthony G; Shara, Nawar M; Welty, Thomas K

    2010-12-01

    Large studies of extended families usually collect valuable phenotypic data that may have scientific value for purposes other than testing genetic hypotheses if the families were not selected in a biased manner. These purposes include assessing population-based associations of diseases with risk factors/covariates and estimating population characteristics such as disease prevalence and incidence. Relatedness among participants however, violates the traditional assumption of independent observations in these classic analyses. The commonly used adjustment method for relatedness in population-based analyses is to use marginal models, in which clusters (families) are assumed to be independent (unrelated) with a simple and identical covariance (family) structure such as those called independent, exchangeable and unstructured covariance structures. However, using these simple covariance structures may not be optimally appropriate for outcomes collected from large extended families, and may under- or over-estimate the variances of estimators and thus lead to uncertainty in inferences. Moreover, the assumption that families are unrelated with an identical family structure in a marginal model may not be satisfied for family studies with large extended families. The aim of this paper is to propose models incorporating marginal models approaches with a covariance structure for assessing population-based associations of diseases with their risk factors/covariates and estimating population characteristics for epidemiological studies while adjusting for the complicated relatedness among outcomes (continuous/categorical, normally/non-normally distributed) collected from large extended families. We also discuss theoretical issues of the proposed models and show that the proposed models and covariance structure are appropriate for and capable of achieving the aim.

  3. Mental health indicators fifty years later: A population-based study of men with histories of child sexual abuse.

    PubMed

    Easton, Scott D; Kong, Jooyoung

    2017-01-01

    Childhood sexual abuse (CSA) is a widely acknowledged trauma that affects a substantial number of boys/men and has the potential to undermine mental health across the lifespan. Despite the topic's importance, few studies have examined the long-term effects of CSA on mental health in middle and late life for men. Most empirical studies on the effects of CSA have been conducted with women, non-probability samples, and samples of young or emerging adults with inadequate control variables. Based on complex trauma theory, the current study investigated: a) the effect of CSA on mental health outcomes (depressive symptoms, somatic symptom severity, hostility) in late life for men, and b) the moderating effects of childhood adversities and masculine norms in the relationship between CSA and the three mental health outcomes. Using a population-based sample from the 2004-2005 Wisconsin Longitudinal Study, multivariate analyses found that CSA was positively related to both depressive and somatic symptoms and increased the likelihood of hostility for men who reported a history of CSA. Both childhood adversities and masculine norms were positively related to the three outcomes for the entire sample. Among CSA survivors, childhood adversities exerted a moderating effect in terms of depressive symptoms. Mental health practitioners should include CSA and childhood adversities in assessment and treatment with men. To more fully understand the effects of CSA, future studies are needed that use longitudinal designs, compare male and female survivors, and examine protective mechanisms such as social support.

  4. Prevalence of Intimate Partner Violence, Stalking, and Sexual Violence Among Active Duty Women and Wives of Active Duty Men - Comparisons with Women in the U.S. General Population, 2010

    DTIC Science & Technology

    2013-03-01

    Prevalence of Intimate Partner Violence, Stalking, and Sexual Violence Among Active Duty Women and Wives of Active Duty Men—Comparisons with Women...Technical Report Prevalence of Intimate Partner Violence, Sexual Violence, and Stalking among Active Duty Women and Wives of Active Duty Men— Comparisons...the General U.S. Population, Active Duty Women, and Wives of Active Duty Men by Type of Perpetrator — NISVS 2010 Table 3 Prevalence of Contact Sexual

  5. Genetic diversity and population genetics of large lungworms (Dictyocaulus, Nematoda) in wild deer in Hungary.

    PubMed

    Ács, Zoltán; Hayward, Alexander; Sugár, László

    2016-09-01

    Dictyocaulus nematode worms live as parasites in the lower airways of ungulates and can cause significant disease in both wild and farmed hosts. This study represents the first population genetic analysis of large lungworms in wildlife. Specifically, we quantify genetic variation in Dictyocaulus lungworms from wild deer (red deer, fallow deer and roe deer) in Hungary, based on mitochondrial cytochrome c oxidase subunit 1 (cox1) sequence data, using population genetic and phylogenetic analyses. The studied Dictyocaulus taxa display considerable genetic diversity. At least one cryptic species and a new parasite-host relationship are revealed by our molecular study. Population genetic analyses for Dictyocaulus eckerti revealed high gene flow amongst weakly structured spatial populations that utilise the three host deer species considered here. Our results suggest that D. eckerti is a widespread generalist parasite in ungulates, with a diverse genetic backround and high evolutionary potential. In contrast, evidence of cryptic genetic structure at regional geographic scales was observed for Dictyocaulus capreolus, which infects just one host species, suggesting it is a specialist within the studied area. D. capreolus displayed lower genetic diversity overall, with only moderate gene flow compared to the closely related D. eckerti. We suggest that the differing vagility and dispersal behaviour of hosts are important contributing factors to the population structure of lungworms, and possibly other nematode parasites with single-host life cycles. Our findings are of relevance for the management of lungworms in deer farms and wild deer populations.

  6. fastSTRUCTURE: variational inference of population structure in large SNP data sets.

    PubMed

    Raj, Anil; Stephens, Matthew; Pritchard, Jonathan K

    2014-06-01

    Tools for estimating population structure from genetic data are now used in a wide variety of applications in population genetics. However, inferring population structure in large modern data sets imposes severe computational challenges. Here, we develop efficient algorithms for approximate inference of the model underlying the STRUCTURE program using a variational Bayesian framework. Variational methods pose the problem of computing relevant posterior distributions as an optimization problem, allowing us to build on recent advances in optimization theory to develop fast inference tools. In addition, we propose useful heuristic scores to identify the number of populations represented in a data set and a new hierarchical prior to detect weak population structure in the data. We test the variational algorithms on simulated data and illustrate using genotype data from the CEPH-Human Genome Diversity Panel. The variational algorithms are almost two orders of magnitude faster than STRUCTURE and achieve accuracies comparable to those of ADMIXTURE. Furthermore, our results show that the heuristic scores for choosing model complexity provide a reasonable range of values for the number of populations represented in the data, with minimal bias toward detecting structure when it is very weak. Our algorithm, fastSTRUCTURE, is freely available online at http://pritchardlab.stanford.edu/structure.html.

  7. How populations differentiate despite gene flow: sexual and natural selection drive phenotypic divergence within a land fish, the Pacific leaping blenny

    PubMed Central

    2014-01-01

    Background Divergence between populations in reproductively important features is often vital for speciation. Many studies attempt to identify the cause of population differentiation in phenotype through the study of a specific selection pressure. Holistic studies that consider the interaction of several contrasting forms of selection are more rare. Most studies also fail to consider the history of connectivity among populations and the potential for genetic drift or gene flow to facilitate or limit phenotypic divergence. We examined the interacting effects of natural selection, sexual selection and the history of connectivity on phenotypic differentiation among five populations of the Pacific leaping blenny (Alticus arnoldorum), a land fish endemic to the island of Guam. Results We found key differences among populations in two male ornaments—the size of a prominent head crest and conspicuousness of a coloured dorsal fin—that reflected a trade-off between the intensity of sexual selection (male biased sex ratios) and natural selection (exposure to predators). This differentiation in ornamentation has occurred despite evidence suggesting extensive gene flow among populations, which implies that the change in ornament expression has been recent (and potentially plastic). Conclusions Our study provides an early snapshot of divergence in reproductively important features that, regardless of whether it reflects genetic or plastic changes in phenotype, could ultimately form a reproductive barrier among populations. PMID:24884492

  8. Selfish Mitochondrial DNA Proliferates and Diversifies in Small, but not Large, Experimental Populations of Caenorhabditis briggsae

    PubMed Central

    Phillips, Wendy S.; Coleman-Hulbert, Anna L.; Weiss, Emily S.; Howe, Dana K.; Ping, Sita; Wernick, Riana I.; Estes, Suzanne; Denver, Dee R.

    2015-01-01

    Evolutionary interactions across levels of biological organization contribute to a variety of fundamental processes including genome evolution, reproductive mode transitions, species diversification, and extinction. Evolutionary theory predicts that so-called “selfish” genetic elements will proliferate when the host effective population size (Ne) is small, but direct tests of this prediction remain few. We analyzed the evolutionary dynamics of deletion-containing mitochondrial DNA (ΔmtDNA) molecules, previously characterized as selfish elements, in six different natural strains of the nematode Caenorhabditis briggsae allowed to undergo experimental evolution in a range of population sizes (N = 1, 10, 100, and 1,000) for a maximum of 50 generations. Mitochondrial DNA (mtDNA) was analyzed for replicate lineages at each five-generation time point. Ten different ΔmtDNA molecule types were observed and characterized across generations in the experimental populations. Consistent with predictions from evolutionary theory, lab lines evolved in small-population sizes (e.g., nematode N = 1) were more susceptible to accumulation of high levels of preexisting ΔmtDNA compared with those evolved in larger populations. New ΔmtDNA elements were observed to increase in frequency and persist across time points, but almost exclusively at small population sizes. In some cases, ΔmtDNA levels decreased across generations when population size was large (nematode N = 1,000). Different natural strains of C. briggsae varied in their susceptibilities to ΔmtDNA accumulation, owing in part to preexisting compensatory mtDNA alleles in some strains that prevent deletion formation. This analysis directly demonstrates that the evolutionary trajectories of ΔmtDNA elements depend upon the population-genetic environments and molecular-genetic features of their hosts. PMID:26108490

  9. A Population-Based Study of Childhood Sexual Contact in China: Prevalence and Long-Term Consequences

    ERIC Educational Resources Information Center

    Luo, Ye; Parish, William L.; Laumann, Edward O.

    2008-01-01

    Objectives: This study provides national estimates of the prevalence of childhood sexual contact and its association with sexual well-being and psychological distress among adults in China. Method: A national stratified probability sample of 1,519 women and 1,475 men aged 20-64 years in urban China completed a computer-administered survey in…

  10. Lifestyle and Risk of Premature Sexual Activity in a High School Population of Seventh-Day Adventists: Valuegenesis 1989.

    ERIC Educational Resources Information Center

    Weinbender, Miriam L. M.; Rossignol, Annette MacKay

    1996-01-01

    Evaluated Adventist lifestyle as a modification of popular American culture which reduces the risk of early sexual activity in adolescents and thus also reduces the risk for both STDs and teen pregnancy. Data analysis demonstrated a wide variety of behaviors were associated with premature sexual activity, including previously reported high-risk…

  11. Management of fish populations in large rivers: a review of tools and approaches

    USGS Publications Warehouse

    Petts, Geoffrey E.; Imhoff, Jack G.; Manny, Bruce A.; Maher, John F. B.; Weisberg, Stephen B.

    1989-01-01

    In common with most branches of science, the management of riverine fish populations is characterised by reductionist and isolationist philosophies. Traditional fish management focuses on stocking and controls on fishing. This paper presents a concensus of scientists involved in the LARS workshop on the management of fish populations in large rivers. A move towards a more holistic philosophy is advocated, with fish management forming an integral part of sustainable river development. Based upon a questionnaire survey of LARS members, with wide-ranging expertise and experience from all parts of the world, lists of management tools currently in use are presented. Four categories of tools are described: flow, water-quality, habitat, and biological. The potential applications of tools for fish management in large rivers is discussed and research needs are identified. The lack of scientific evaluations of the different tools remains the major constraint to their wider application.

  12. Can simple population genetic models reconcile partial match frequencies observed in large forensic databases?

    PubMed

    Mueller, Laurence D

    2008-08-01

    A recent study of partial matches in the Arizona offender database of DNA profiles has revealed a large number of nine and ten locus matches. I use simple models that incorporate the product rule, population substructure, and relatedness to predict the expected number of matches in large databases. I find that there is a relatively narrow window of parameter values that can plausibly describe the Arizona results. Further research could help determine if the Arizona samples are congruent with some of the models presented here or whether fundamental assumptions for predicting these match frequencies requires adjustments.

  13. Variable responses to large-scale climate change in European Parus populations.

    PubMed Central

    Visser, Marcel E; Adriaensen, Frank; Van Balen, Johan H; Blondel, Jacques; Dhondt, André A; Van Dongen, Stefan; Du Feu, Chris; Ivankina, Elena V; Kerimov, Anvar B; De Laet, Jenny; Matthysen, Erik; McCleery, Robin; Orell, Markku; Thomson, David L

    2003-01-01

    Spring temperatures in temperate regions have increased over the past 20 years and many organisms have responded to this increase by advancing the timing of their growth and reproduction. However, not all populations show an advancement of phenology. Understanding why some populations advance and others do not will give us insight into the possible constraints and selection pressures on the advancement of phenology. By combining two decades of data on 24 populations of tits (Parus sp.) from six European countries, we show that the phenological response to large-scale changes in spring temperature varies across a species' range, even between populations situated close to each other. We show that this variation cannot be fully explained by variation in the temperature change during the pre- and post-laying periods, as recently suggested. Instead, we find evidence for a link between rising temperatures and the frequency of second broods, which results in complex shifts in the laying dates of first clutches. Our results emphasize the need to consider links between different life-history parameters in order to predict the ecological consequences of large-scale climate changes. PMID:12639315

  14. Biotic and abiotic factors predicting the global distribution and population density of an invasive large mammal

    PubMed Central

    Lewis, Jesse S.; Farnsworth, Matthew L.; Burdett, Chris L.; Theobald, David M.; Gray, Miranda; Miller, Ryan S.

    2017-01-01

    Biotic and abiotic factors are increasingly acknowledged to synergistically shape broad-scale species distributions. However, the relative importance of biotic and abiotic factors in predicting species distributions is unclear. In particular, biotic factors, such as predation and vegetation, including those resulting from anthropogenic land-use change, are underrepresented in species distribution modeling, but could improve model predictions. Using generalized linear models and model selection techniques, we used 129 estimates of population density of wild pigs (Sus scrofa) from 5 continents to evaluate the relative importance, magnitude, and direction of biotic and abiotic factors in predicting population density of an invasive large mammal with a global distribution. Incorporating diverse biotic factors, including agriculture, vegetation cover, and large carnivore richness, into species distribution modeling substantially improved model fit and predictions. Abiotic factors, including precipitation and potential evapotranspiration, were also important predictors. The predictive map of population density revealed wide-ranging potential for an invasive large mammal to expand its distribution globally. This information can be used to proactively create conservation/management plans to control future invasions. Our study demonstrates that the ongoing paradigm shift, which recognizes that both biotic and abiotic factors shape species distributions across broad scales, can be advanced by incorporating diverse biotic factors. PMID:28276519

  15. Prevalence of antibodies to hepatitis C virus in populations at low and high risk for sexually transmitted diseases in Rio de Janeiro.

    PubMed

    Edelenyi-Pinto, M; Carvalho, A P; Nogueira, C; Ferreira Júnior, O; Schechter, M

    1993-01-01

    In order to investigate the sexual transmission of the Hepatitis C Virus (HCV), the prevalence of specific antibodies in populations at high and low risk for sexually transmitted diseases (STDs) was evaluated. The population at low risk for STDs was composed of persons who voluntarily donated blood at the Hospital Universitário Clementino Fraga Filho (HUCFF) between July and November, 1990 (n = 2494). The population at high risk for STDs was drawn from an ongoing study on the natural history of Human Immunodeficiency Virus (HIV) infection (n = 210, 187 with sexual risk factors for HIV infection). All samples were screened using a first generation ELISA. Repeat reactive samples were then tested in a second generation RIBA. For all ELISA positive samples, two sex and age-matched ELISA negative controls were selected. Data pertaining to the presence of antibodies to the Hepatitis B core antigen (anti-HBC antibodies) and to Treponema pallidum were abstracted from the medical records. The prevalence of RIBA 2 confirmed HCV infection among the blood donors was 2.08%, which is well above the reported prevalence in similar populations from developed western countries. Among the HIV infected homosexuals, the encountered prevalence was 7.96% (p < 0.0005). For the whole group with sexually acquired HIV infection, the prevalence was 8.02% (p < 0.000005). Anti-HBc antibodies were more frequently present in anti-HCV RIBA-2 confirmed positive blood donors than in controls (p < 0.001). 33.3% of the HCV-positive blood donors and 11.04% controls were found to be anti-HBc positive (p < 0.0005).(ABSTRACT TRUNCATED AT 250 WORDS)

  16. New method of estimating inbreeding in large semi-isolated populations with application to historic Britain.

    PubMed

    Pattison, J E

    2001-01-01

    The purpose of this paper is to introduce a new method of estimating inbreeding in large, relatively isolated, populations over historic times, to demonstrate its application, and indicate some of its limitations and future developments. The method is based on the "paradox" of genealogy, and requires only that the variation of the population size be known, at least reasonably well, over an extended historic period. In this study a method has been developed to model this "paradox" which allows an estimation of the minimum level of inbreeding necessary for a given population curve in terms of values of Pearl's coefficients for each generation. As an example, the method is applied to the population of Britain. It is found that the frequency of siblings occurring in the same generation of a pedigree varies with the population size according to the Fermi-Dirac equation of statistical physics. The effect of introducing a single known estimate of inbreeding into the model is to make the otherwise diverse results for both the actual numbers of ancestors in a generation and the corresponding coefficients of inbreeding to converge.

  17. HIV-Related Risk Behaviors Among Male High School Students Who Had Sexual Contact with Males - 17 Large Urban School Districts, United States, 2009-2013.

    PubMed

    Kann, Laura; Olsen, Emily O'Malley; Kinchen, Steve; Morris, Elana; Wolitski, Richard J

    2016-02-12

    Young persons aged 13-24 years accounted for an estimated 22% of all new diagnoses of human immunodeficiency virus (HIV) infection in the United States in 2014. Most new HIV diagnoses among youths occur among males who have sex with males (MSM). Among all MSM, young black MSM accounted for the largest number of new HIV diagnoses in 2014 (1). To determine whether the prevalence of HIV-related risk behaviors among black male high school students who had sexual contact with males differed from the prevalence among white and Hispanic male students who had sexual contact with males, potentially contributing to the racial/ethnic disparities in new HIV diagnoses, CDC analyzed data from Youth Risk Behavior Surveys conducted by 17 large urban school districts during 2009-2013. Although other studies have examined HIV-related risk behaviors among MSM (2,3), less is known about MSM aged <18 years. Black male students who had sexual contact with males had a lower or similar prevalence of most HIV-related risk behaviors than did white and Hispanic male students who had sexual contact with males. These findings highlight the need to increase access to effective HIV prevention strategies for all young MSM.

  18. The Strategies of Heterosexuals from Large Metropolitan Areas for Assessing the Risks of Exposure to HIV or Other Sexually Transmitted Infections from Partners Met Online.

    PubMed

    Siegel, Karolynn; Lekas, Helen-Maria; Onaga, Marie; Verni, Rachel; Gunn, Hamish

    2017-03-24

    Heterosexuals' use of the Internet for meeting romantic or sexual partners is rapidly increasing, raising concerns about the Internet's potential to facilitate encounters that place individuals at risk for acquiring HIV or other sexually transmitted infections (STIs). For example, online sharing of personal information and self-revelations can foster virtual intimacy, promoting a false sense of familiarity that might accelerate progression to unprotected sex. Therefore, it is critical to understand how those who meet sexual partners online attempt to assess the possible risk of acquiring HIV or STIs posed by having unprotected sex with a new partner and decide whether to use a condom. To investigate this issue, in-depth interviews were conducted with a diverse sample of heterosexual male and female participants from large metropolitan cities who had had unprotected vaginal or anal sex with at least two partners met online in the past 3 months. With few exceptions, participants relied on faulty strategies and heuristics to estimate these risks; yet, most engaged in unprotected sex at their first meeting or very soon afterward. While some seemed to try to make a genuine effort to arrive at a reliable assessment of the HIV risk posed, most appeared to be looking for a way to justify their desire and intention to have unprotected sex. The findings suggest the need for more HIV and sexual health education targeted at heterosexuals, especially for those who go online to meet partners.

  19. Evidence for an Intervening Stellar Population Toward the Large Magellanic Cloud

    NASA Astrophysics Data System (ADS)

    Zaritsky, Dennis; Lin, D. N. C.

    1997-12-01

    We identify a vertical extension of the red clump stars in the color magnitude diagram (CMD) of a section of the Large Magellanic Cloud (LMC). The distribution of stars in this extension is indistinguishable in the U, B, V, and I bands - confirming that the detection is real and placing a strong constraint on models of this stellar population. After subtracting the principal red clump component, we find a peak in the residual stellar distribution that is ˜0.9 mag brighter than the peak of the principal red clump distribution. We consider and reject the following possible explanations for this population: inhomogeneous reddening, Galactic disk stars, random blends of red clump stars, correlated blends of red clump stars (binaries), evolution of the red clump stars, and red clump stars from a younger LMC stellar population. Combinations of these effects cannot be ruled out as the origin of this stellar population. A natural interpretation of this new population is that it consists of red clump stars that are closer to us than those in the LMC. We derive a distance for this population of 33 to 35 kpc, although the measurement is sensitive to the modeling of the LMC red clump component. We find corroborating evidence for this interpretation in Holtzman et al.'s (1997, AJ, 113, 656) Hubble Space Telescope CMD of the LMC field stars. The derived distance and projected angular surface density of these stars relative to the LMC stars ( ≤5 to 7%) are consistent with (1) models that attribute the observed microlensing lensing optical depth (Alcock et al. 1997, ApJ, 486, 697) to a distinct foreground stellar population (Zhao 1997, preprint, astro-ph/9703097) and (2) tidal models of the interaction between the LMC and the Milky Way (Lin et al. 1995, ApJ, 439, 652). The first result suggests that the Galactic halo may contain few, if any, purely halo MACHO objects. The second result suggests that this new population may be evidence of a tidal tail from the interaction

  20. Sexual Health

    MedlinePlus

    ... Statistics Resources on infectious diseases, reproductive health and sexual violence prevention. Sexually Transmitted Diseases Up-to-date Sexually ... Health Answers to women's and men's reproductive concerns Sexual Violence Prevention Sexual violence affects all people, particularly women ...

  1. Population genetic structure of Bellamya aeruginosa (Mollusca: Gastropoda: Viviparidae) in China: weak divergence across large geographic distances.

    PubMed

    Gu, Qian H; Husemann, Martin; Ding, Baoqing; Luo, Zhi; Xiong, Bang X

    2015-11-01

    Bellamya aeruginosa is a widely distributed Chinese freshwater snail that is heavily harvested, and its natural habitats are under severe threat due to fragmentation and loss. We were interested whether the large geographic distances between populations and habitat fragmentation have led to population differentiation and reduced genetic diversity in the species. To estimate the genetic diversity and population structure of B. aeruginosa, 277 individuals from 12 populations throughout its distribution range across China were sampled: two populations were sampled from the Yellow River system, eight populations from the Yangtze River system, and two populations from isolated plateau lakes. We used seven microsatellite loci and mitochondrial cytochrome oxidase I sequences to estimate population genetic parameters and test for demographic fluctuations. Our results showed that (1) the genetic diversity of B. aeruginosa was high for both markers in most of the studied populations and effective population sizes appear to be large, (2) only very low and mostly nonsignificant levels of genetic differentiation existed among the 12 populations, gene flow was generally high, and (3) relatively weak geographic structure was detected despite large geographic distances between populations. Further, no isolation by linear or stream distance was found among populations within the Yangtze River system and no signs of population bottlenecks were detected. Gene flow occurred even between far distant populations, possibly as a result of passive dispersal during flooding events, zoochoric dispersal, and/or anthropogenic translocations explaining the lack of stronger differentiation across large geographic distances. The high genetic diversity of B. aeruginosa and the weak population differentiation are likely the results of strong gene flow facilitated by passive dispersal and large population sizes suggesting that the species currently is not of conservation concern.

  2. Prevalence and risk factors of early onset of sexual intercourse in a random sample of a multiethnic adolescent population in French Guiana.

    PubMed

    Ayhan, Gülen; Martin, Loic; Levy-Loeb, Mathieu; Thomas, Stéphanie; Euzet, Géneviève; Van Melle, Astrid; Parriault, Marie-Claire; Basurko, Célia; Nacher, Mathieu

    2015-01-01

    French Guiana, a French overseas department in South America, has been classified epidemic for HIV. This territory is consisting of a very young population with almost 45% of them being younger than 20 years of age. Delaying the onset of first sexual intercourse (SI) is one of the major objectives to fight HIV infection in adolescents. The objective of this study is to identify the age of first SI and the risk factors of early onset. A behavioural surveillance survey among students living on the coastline and alongside the Maroni River was conducted in 2011/2012. A total of 1603 students filled out the survey. While 60% had already SI, the mean age of first intercourse was 12.1 years for boys and 13.9 years for girls. Accordingly, over 90% had a premature onset of SI. Risk factors are age, male gender, living alongside the Maroni River, another language than the French being mother tongue, not being religious, alcohol and cannabis consumption and a bad attitude towards condom use. Risk factors for girls are an older first sexual partner, having more than three lifetime sexual partners and condom rupture. Evidence-based implementation with respect of local and socio-demographic aspects is necessary to improve youths' appreciation of SI and related risk of sexual transmitted diseases.

  3. Category Specificity of Self-Reported Sexual Attraction and Viewing Times to Male and Female Models in a Large U.S. Sample: Sex, Sexual Orientation, and Demographic Effects.

    PubMed

    Lippa, Richard A

    2017-01-01

    Recent research has documented large and robust sex differences in the category specificity of self-reported sexual attraction and viewing times to men and women, with men showing more polarized responses to the two sexes than women. However, this research has been limited by the use of small and restricted samples. To address this, the current study assessed a representative sample of more than 2800 U.S. adults on demographic and attitudinal variables and on two measures of category specificity: one based on self-reported sexual attraction and the other based on viewing times to male and female swimsuit models. Key findings were replicated. On average, men were considerably more category specific in self-reported sexual attraction and viewing times than women, and this was true for both heterosexual and homosexual participants. Self-identified bisexual and asexual participants tended to be lower on category specificity than other groups. Although demographic and attitudinal factors such as age, ethnicity, state and region of residence, social class, political liberalism-conservatism, and religiousness were sometimes weakly related to category specificity, sex differences in category specificity remained robust despite demographic and attitudinal variation.

  4. The limits of weak selection and large population size in evolutionary game theory.

    PubMed

    Sample, Christine; Allen, Benjamin

    2017-03-28

    Evolutionary game theory is a mathematical approach to studying how social behaviors evolve. In many recent works, evolutionary competition between strategies is modeled as a stochastic process in a finite population. In this context, two limits are both mathematically convenient and biologically relevant: weak selection and large population size. These limits can be combined in different ways, leading to potentially different results. We consider two orderings: the [Formula: see text] limit, in which weak selection is applied before the large population limit, and the [Formula: see text] limit, in which the order is reversed. Formal mathematical definitions of the [Formula: see text] and [Formula: see text] limits are provided. Applying these definitions to the Moran process of evolutionary game theory, we obtain asymptotic expressions for fixation probability and conditions for success in these limits. We find that the asymptotic expressions for fixation probability, and the conditions for a strategy to be favored over a neutral mutation, are different in the [Formula: see text] and [Formula: see text] limits. However, the ordering of limits does not affect the conditions for one strategy to be favored over another.

  5. Exploring associations in developmental trends of adolescent substance use and risky sexual behavior in a high-risk population.

    PubMed

    Duncan, S C; Strycker, L A; Duncan, T E

    1999-02-01

    This study examined associations between the development of adolescent alcohol, cigarette, and marijuana use and risky sexual behavior, over time, using latent growth modeling methodology. Gender differences in the development and relationships between use of substances and risky sexual behavior were also examined. Participants were 257 adolescents (mean age = 15.96 years) assessed at three time points over an 18-month period. The intercepts of marijuana with cigarettes and alcohol, and all three substances with risky sexual behavior were significantly related. Development of the three substances showed similar patterns and development of cigarette use covaried with development of risky sexual behavior. There were no significant differences for boys and girls in these relationships. Results are discussed in relation to the need for greater understanding of nonsexual and sex-related problem behaviors and for analyses examining development and change in these behaviors during adolescence.

  6. High Accuracy Decoding of Dynamical Motion from a Large Retinal Population

    PubMed Central

    Marre, Olivier; Botella-Soler, Vicente; Simmons, Kristina D.; Mora, Thierry; Tkačik, Gašper; Berry, Michael J.

    2015-01-01

    Motion tracking is a challenge the visual system has to solve by reading out the retinal population. It is still unclear how the information from different neurons can be combined together to estimate the position of an object. Here we recorded a large population of ganglion cells in a dense patch of salamander and guinea pig retinas while displaying a bar moving diffusively. We show that the bar’s position can be reconstructed from retinal activity with a precision in the hyperacuity regime using a linear decoder acting on 100+ cells. We then took advantage of this unprecedented precision to explore the spatial structure of the retina’s population code. The classical view would have suggested that the firing rates of the cells form a moving hill of activity tracking the bar’s position. Instead, we found that most ganglion cells in the salamander fired sparsely and idiosyncratically, so that their neural image did not track the bar. Furthermore, ganglion cell activity spanned an area much larger than predicted by their receptive fields, with cells coding for motion far in their surround. As a result, population redundancy was high, and we could find multiple, disjoint subsets of neurons that encoded the trajectory with high precision. This organization allows for diverse collections of ganglion cells to represent high-accuracy motion information in a form easily read out by downstream neural circuits. PMID:26132103

  7. Patient Population Loss At A Large Pioneer Accountable Care Organization And Implications For Refining The Program.

    PubMed

    Hsu, John; Price, Mary; Spirt, Jenna; Vogeli, Christine; Brand, Richard; Chernew, Michael E; Chaguturu, Sreekanth K; Mohta, Namita; Weil, Eric; Ferris, Timothy

    2016-03-01

    There is an ongoing move toward payment models that hold providers increasingly accountable for the care of their patients. The success of these new models depends in part on the stability of patient populations. We investigated the amount of population turnover in a large Medicare Pioneer accountable care organization (ACO) in the period 2012-14. We found that substantial numbers of beneficiaries became part of or left the ACO population during that period. For example, nearly one-third of beneficiaries who entered in 2012 left before 2014. Some of this turnover reflected that of ACO physicians-that is, beneficiaries whose physicians left the ACO were more likely to leave than those whose physicians remained. Some of the turnover also reflected changes in care delivery. For example, beneficiaries who were active in a care management program were less likely to leave the ACO than similar beneficiaries who had not yet started such a program. We recommend policy changes to increase the stability of ACO beneficiary populations, such as permitting lower cost sharing for care received within an ACO and requiring all beneficiaries to identify their primary care physician before being linked to an ACO.

  8. Population genetic divergence corresponds with species-level biodiversity patterns in the large genus Begonia.

    PubMed

    Hughes, M; Hollingsworth, P M

    2008-06-01

    Begonia is one of the largest angiosperm genera, containing over 1500 species. Some aspects of the distribution of biodiversity in the genus, such as the geographical restrictions of monophyletic groups, the rarity and morphological variability of widespread species, and a preponderance of narrow endemics, suggest that restricted gene flow may have been a factor in the formation of so many species. In order to investigate whether this inference based on large-scale patterns is supported by data at the population level, we examined the distribution of genetic variation within Begonia sutherlandii in the indigenous forests of Kwazulu-Natal, South Africa, using microsatellite markers. Despite the species being predominantly outbreeding, we found high and significant levels of population structure (standardized =F'ST= 0.896). Even within individual populations, there was evidence for clear differentiation of subpopulations. There is thus congruence in evolutionary patterns ranging from interspecific phylogeny, the distribution of individual species, to the levels of population differentiation. Despite this species-rich genus showing a pan-tropical distribution, these combined observations suggest that differentiation occurs over very local scales. Although strongly selected allelic variants can maintain species cohesion with only low levels of gene flow, we hypothesize that in Begonia, gene flow levels are often so low, that divergence in allopatry is likely to be a frequent occurrence, and the lack of widespread species may in part be attributable to a lack of a mechanism for holding them together.

  9. Spike Detection for Large Neural Populations Using High Density Multielectrode Arrays.

    PubMed

    Muthmann, Jens-Oliver; Amin, Hayder; Sernagor, Evelyne; Maccione, Alessandro; Panas, Dagmara; Berdondini, Luca; Bhalla, Upinder S; Hennig, Matthias H

    2015-01-01

    An emerging generation of high-density microelectrode arrays (MEAs) is now capable of recording spiking activity simultaneously from thousands of neurons with closely spaced electrodes. Reliable spike detection and analysis in such recordings is challenging due to the large amount of raw data and the dense sampling of spikes with closely spaced electrodes. Here, we present a highly efficient, online capable spike detection algorithm, and an offline method with improved detection rates, which enables estimation of spatial event locations at a resolution higher than that provided by the array by combining information from multiple electrodes. Data acquired with a 4096 channel MEA from neuronal cultures and the neonatal retina, as well as synthetic data, was used to test and validate these methods. We demonstrate that these algorithms outperform conventional methods due to a better noise estimate and an improved signal-to-noise ratio (SNR) through combining information from multiple electrodes. Finally, we present a new approach for analyzing population activity based on the characterization of the spatio-temporal event profile, which does not require the isolation of single units. Overall, we show how the improved spatial resolution provided by high density, large scale MEAs can be reliably exploited to characterize activity from large neural populations and brain circuits.

  10. Spike Detection for Large Neural Populations Using High Density Multielectrode Arrays

    PubMed Central

    Muthmann, Jens-Oliver; Amin, Hayder; Sernagor, Evelyne; Maccione, Alessandro; Panas, Dagmara; Berdondini, Luca; Bhalla, Upinder S.; Hennig, Matthias H.

    2015-01-01

    An emerging generation of high-density microelectrode arrays (MEAs) is now capable of recording spiking activity simultaneously from thousands of neurons with closely spaced electrodes. Reliable spike detection and analysis in such recordings is challenging due to the large amount of raw data and the dense sampling of spikes with closely spaced electrodes. Here, we present a highly efficient, online capable spike detection algorithm, and an offline method with improved detection rates, which enables estimation of spatial event locations at a resolution higher than that provided by the array by combining information from multiple electrodes. Data acquired with a 4096 channel MEA from neuronal cultures and the neonatal retina, as well as synthetic data, was used to test and validate these methods. We demonstrate that these algorithms outperform conventional methods due to a better noise estimate and an improved signal-to-noise ratio (SNR) through combining information from multiple electrodes. Finally, we present a new approach for analyzing population activity based on the characterization of the spatio-temporal event profile, which does not require the isolation of single units. Overall, we show how the improved spatial resolution provided by high density, large scale MEAs can be reliably exploited to characterize activity from large neural populations and brain circuits. PMID:26733859

  11. Emergence of a super-synchronized mobbing state in a large population of coupled chemical oscillators

    NASA Astrophysics Data System (ADS)

    Ghoshal, Gourab; Muñuzuri, Alberto P.; Pérez-Mercader, Juan

    2016-01-01

    Oscillatory phenomena are ubiquitous in Nature. The ability of a large population of coupled oscillators to synchronize constitutes an important mechanism to express information and establish communication among members. To understand such phenomena, models and experimental realizations of globally coupled oscillators have proven to be invaluable in settings as varied as chemical, biological and physical systems. A variety of rich dynamical behavior has been uncovered, although usually in the context of a single state of synchronization or lack thereof. Through the experimental and numerical study of a large population of discrete chemical oscillators, here we report on the unexpected discovery of a new phenomenon revealing the existence of dynamically distinct synchronized states reflecting different degrees of communication. Specifically, we discover a novel large-amplitude super-synchronized state separated from the conventionally reported synchronized and quiescent states through an unusual sharp jump transition when sampling the strong coupling limit. Our results assume significance for further elucidating globally coherent phenomena, such as in neuropathologies, bacterial cell colonies, social systems and semiconductor lasers.

  12. Emergence of a super-synchronized mobbing state in a large population of coupled chemical oscillators

    PubMed Central

    Ghoshal, Gourab; Muñuzuri, Alberto P.; Pérez-Mercader, Juan

    2016-01-01

    Oscillatory phenomena are ubiquitous in Nature. The ability of a large population of coupled oscillators to synchronize constitutes an important mechanism to express information and establish communication among members. To understand such phenomena, models and experimental realizations of globally coupled oscillators have proven to be invaluable in settings as varied as chemical, biological and physical systems. A variety of rich dynamical behavior has been uncovered, although usually in the context of a single state of synchronization or lack thereof. Through the experimental and numerical study of a large population of discrete chemical oscillators, here we report on the unexpected discovery of a new phenomenon revealing the existence of dynamically distinct synchronized states reflecting different degrees of communication. Specifically, we discover a novel large-amplitude super-synchronized state separated from the conventionally reported synchronized and quiescent states through an unusual sharp jump transition when sampling the strong coupling limit. Our results assume significance for further elucidating globally coherent phenomena, such as in neuropathologies, bacterial cell colonies, social systems and semiconductor lasers. PMID:26753772

  13. Emergence of a super-synchronized mobbing state in a large population of coupled chemical oscillators.

    PubMed

    Ghoshal, Gourab; Muñuzuri, Alberto P; Pérez-Mercader, Juan

    2016-01-12

    Oscillatory phenomena are ubiquitous in Nature. The ability of a large population of coupled oscillators to synchronize constitutes an important mechanism to express information and establish communication among members. To understand such phenomena, models and experimental realizations of globally coupled oscillators have proven to be invaluable in settings as varied as chemical, biological and physical systems. A variety of rich dynamical behavior has been uncovered, although usually in the context of a single state of synchronization or lack thereof. Through the experimental and numerical study of a large population of discrete chemical oscillators, here we report on the unexpected discovery of a new phenomenon revealing the existence of dynamically distinct synchronized states reflecting different degrees of communication. Specifically, we discover a novel large-amplitude super-synchronized state separated from the conventionally reported synchronized and quiescent states through an unusual sharp jump transition when sampling the strong coupling limit. Our results assume significance for further elucidating globally coherent phenomena, such as in neuropathologies, bacterial cell colonies, social systems and semiconductor lasers.

  14. Influences of clonality on plant sexual reproduction

    PubMed Central

    Barrett, Spencer C. H.

    2015-01-01

    Flowering plants possess an unrivaled diversity of mechanisms for achieving sexual and asexual reproduction, often simultaneously. The commonest type of asexual reproduction is clonal growth (vegetative propagation) in which parental genotypes (genets) produce vegetative modules (ramets) that are capable of independent growth, reproduction, and often dispersal. Clonal growth leads to an expansion in the size of genets and increased fitness because large floral displays increase fertility and opportunities for outcrossing. Moreover, the clonal dispersal of vegetative propagules can assist “mate finding,” particularly in aquatic plants. However, there are ecological circumstances in which functional antagonism between sexual and asexual reproductive modes can negatively affect the fitness of clonal plants. Populations of heterostylous and dioecious species have a small number of mating groups (two or three), which should occur at equal frequency in equilibrium populations. Extensive clonal growth and vegetative dispersal can disrupt the functioning of these sexual polymorphisms, resulting in biased morph ratios and populations with a single mating group, with consequences for fertility and mating. In populations in which clonal propagation predominates, mutations reducing fertility may lead to sexual dysfunction and even the loss of sex. Recent evidence suggests that somatic mutations can play a significant role in influencing fitness in clonal plants and may also help explain the occurrence of genetic diversity in sterile clonal populations. Highly polymorphic genetic markers offer outstanding opportunities for gaining novel insights into functional interactions between sexual and clonal reproduction in flowering plants. PMID:26195747

  15. Evolutionary potential of a large marine vertebrate: quantitative genetic parameters in a wild population.

    PubMed

    Dibattista, Joseph D; Feldheim, Kevin A; Garant, Dany; Gruber, Samuel H; Hendry, Andrew P

    2009-04-01

    Estimating quantitative genetic parameters ideally takes place in natural populations, but relatively few studies have overcome the inherent logistical difficulties. For this reason, no estimates currently exist for the genetic basis of life-history traits in natural populations of large marine vertebrates. And yet such estimates are likely to be important given the exposure of this taxon to changing selection pressures, and the relevance of life-history traits to population productivity. We report such estimates from a long-term (1995-2007) study of lemon sharks (Negaprion brevirostris) conducted at Bimini, Bahamas. We obtained these estimates by genetically reconstructing a population pedigree (117 dams, 487 sires, and 1351 offspring) and then using an "animal model" approach to estimate quantitative genetic parameters. We find significant additive genetic (co)variance, and hence moderate heritability, for juvenile length and mass. We also find substantial maternal effects for these traits at age-0, but not age-1, confirming that genotype-phenotype interactions between mother and offspring are strongest at birth; although these effects could not be parsed into their genetic and nongenetic components. Our results suggest that human-imposed selection pressures (e.g., size-selective harvesting) might impose noteworthy evolutionary change even in large marine vertebrates. We therefore use our findings to explain how maternal effects may sometimes promote maladaptive juvenile traits, and how lemon sharks at different nursery sites may show "constrained local adaptation." We also show how single-generation pedigrees, and even simple marker-based regression methods, can provide accurate estimates of quantitative genetic parameters in at least some natural systems.

  16. Determinants and Time Trends for Ischaemic and Haemorrhagic Stroke in a Large Chinese Population

    PubMed Central

    Guo, Yutao; Wang, Hao; Tao, Tao; Tian, Yingchun; Wang, Yutang; Chen, Yundai; Lip, Gregory Y. H.

    2016-01-01

    Background The clinical epidemiology of stroke has been widely investigated in Caucasian populations, but the changes over time in the proportion of ischaemic to haemorrhagic strokes is less clear, especially in the Chinese population. Aims Our objective was to study the determinants and time trends for ischaemic and haemorrhagic stroke, in relation to age, in a large Chinese population cohort. Methods Using a medical insurance database in the southwest of China from 2001 to 2012, time trends in age-adjusted ischaemic and haemorrhagic stroke incidence and the contributing risk factors associated with age were investigated. Results Among 425,901 individuals without prior stroke (52.4% male, median age 54), the rate of ischaemic stroke (per 1000 patient-years) decreased between 2002–2007, then remained broadly similar between 2008–2012. The rate of haemorrhagic stroke showed a similar trend, being approximately 1.3–1.9 from 2008–2012. Compared to patients age<65, ischaemic and haemorrhagic stroke incidences (rate, 95% confidential interval, CI) were higher in the elderly population (age <65 versus age ≥65: ischaemic: 3.64, 3.33–4.00, vs 14.33, 14.01–14.60; haemorrhagic: 1.09, 1.00–1.10 vs 2.52,2.40–2.70, respectively, both p<0.001). There were no significant differences in haemorrhagic stroke rates between the elderly and the very elderly population. Ischaemic and haemorrhagic stroke shared similar risk factors (age, hypertension, coronary artery disease (CAD), vascular disease, and diabetes mellitus) (all p<0.05). In subjects age<75 years, CAD (7.17, 4.14–12.37) and diabetes mellitus (3.27, 2.42–4.42) contributed most to the developing of haemorrhagic stroke (all p<0.001). Amongst the very elderly, vascular disease (2.24, 1.49–3.37) was an additional major risk factor for haemorrhagic stroke, together with CAD and diabetes mellitus (all p<0.001). Conclusion In this large Chinese cohort, there was an increased risk of ischaemic stroke compared

  17. A Connectionist Modeling Approach to Rapid Analysis of Emergent Social Cognition Properties in Large-Populations

    SciTech Connect

    Perumalla, Kalyan S; Schryver, Jack C

    2009-01-01

    Traditional modeling methodologies, such as those based on rule-based agent modeling, are exhibiting limitations in application to rich behavioral scenarios, especially when applied to large population aggregates. Here, we propose a new modeling methodology based on a well-known "connectionist approach," and articulate its pertinence in new applications of interest. This methodology is designed to address challenges such as speed of model development, model customization, model reuse across disparate geographic/cultural regions, and rapid and incremental updates to models over time.

  18. Large numbers of vertebrates began rapid population decline in the late 19th century

    PubMed Central

    Li, Haipeng; Xiang-Yu, Jinggong; Dai, Guangyi; Gu, Zhili; Ming, Chen; Yang, Zongfeng; Ryder, Oliver A.; Li, Wen-Hsiung; Fu, Yun-Xin; Zhang, Ya-Ping

    2016-01-01

    Accelerated losses of biodiversity are a hallmark of the current era. Large declines of population size have been widely observed and currently 22,176 species are threatened by extinction. The time at which a threatened species began rapid population decline (RPD) and the rate of RPD provide important clues about the driving forces of population decline and anticipated extinction time. However, these parameters remain unknown for the vast majority of threatened species. Here we analyzed the genetic diversity data of nuclear and mitochondrial loci of 2,764 vertebrate species and found that the mean genetic diversity is lower in threatened species than in related nonthreatened species. Our coalescence-based modeling suggests that in many threatened species the RPD began ∼123 y ago (a 95% confidence interval of 20–260 y). This estimated date coincides with widespread industrialization and a profound change in global living ecosystems over the past two centuries. On average the population size declined by ∼25% every 10 y in a threatened species, and the population size was reduced to ∼5% of its ancestral size. Moreover, the ancestral size of threatened species was, on average, ∼22% smaller than that of nonthreatened species. Because the time period of RPD is short, the cumulative effect of RPD on genetic diversity is still not strong, so that the smaller ancestral size of threatened species may be the major cause of their reduced genetic diversity; RPD explains 24.1–37.5% of the difference in genetic diversity between threatened and nonthreatened species. PMID:27872315

  19. Patterns of Variation at Ustilago maydis Virulence Clusters 2A and 19A Largely Reflect the Demographic History of Its Populations

    PubMed Central

    Kellner, Ronny; Hanschke, Christian; Begerow, Dominik

    2014-01-01

    The maintenance of an intimate interaction between plant-biotrophic fungi and their hosts over evolutionary times involves strong selection and adaptative evolution of virulence-related genes. The highly specialised maize pathogen Ustilago maydis is assigned with a high evolutionary capability to overcome host resistances due to its high rates of sexual recombination, large population sizes and long distance dispersal. Unlike most studied fungus-plant interactions, the U. maydis – Zea mays pathosystem lacks a typical gene-for-gene interaction. It exerts a large set of secreted fungal virulence factors that are mostly organised in gene clusters. Their contribution to virulence has been experimentally demonstrated but their genetic diversity within U. maydis remains poorly understood. Here, we report on the intraspecific diversity of 34 potential virulence factor genes of U. maydis. We analysed their sequence polymorphisms in 17 isolates of U. maydis from Europe, North and Latin America. We focused on gene cluster 2A, associated with virulence attenuation, cluster 19A that is crucial for virulence, and the cluster-independent effector gene pep1. Although higher compared to four house-keeping genes, the overall levels of intraspecific genetic variation of virulence clusters 2A and 19A, and pep1 are remarkably low and commensurate to the levels of 14 studied non-virulence genes. In addition, each gene is present in all studied isolates and synteny in cluster 2A is conserved. Furthermore, 7 out of 34 virulence genes contain either no polymorphisms or only synonymous substitutions among all isolates. However, genetic variation of clusters 2A and 19A each resolve the large scale population structure of U. maydis indicating subpopulations with decreased gene flow. Hence, the genetic diversity of these virulence-related genes largely reflect the demographic history of U. maydis populations. PMID:24887029

  20. The effect of psychosocial syndemic production on 4-year HIV incidence and risk behavior in a large cohort of sexually active men who have sex with men

    PubMed Central

    MIMIAGA, Matthew J.; O’CLEIRIGH, Conall; BIELLO, Katie B.; ROBERTSON, Angela M.; SAFREN, Steven A.; COATES, Thomas J.; KOBLIN, Beryl A.; CHESNEY, Margaret A.; DONNELL, Deborah J.; STALL, Ron D.; MAYER, Kenneth H.

    2014-01-01

    Background Cross-sectional studies have suggested that co-occurring epidemics or “syndemics” of psychosocial health problems may accelerate HIV transmission among men who have sex with men (MSM) in the United States. We aimed to assess how five syndemic conditions (depressive symptoms, heavy alcohol use, stimulant use, polydrug use, and childhood sexual abuse) affected HIV incidence and sexual risk behavior over time. Methods Eligible men in a large, prospective cohort of sexually active, HIV-uninfected MSM completed HIV testing and behavioral surveys at baseline and every 6 months for 48 months. We examined interrelationships between psychosocial problems and whether these interactions increased the odds of HIV risk behaviors and risk of seroconversion over study follow-up. Results Among 4295 men, prevalence of psychosocial conditions was substantial at baseline and was positively associated with each other. We identified a statistically significant positive dose-response relationship between numbers of syndemic conditions and HIV seroconversion for all comparisons (with the greatest hazard among those with 4-5 conditions, aHR=8.69; 95% CI: 4.78-15.44). The number of syndemic conditions also predicted increased HIV related risk behaviors over time, which mediated the syndemic-HIV seroconversion association. Conclusions The accumulation of “syndemic” psychosocial problems predicted HIV-related sexual risk behaviors and seroconversion in a large sample of U.S. MSM. Given the high prevalence of syndemic conditions among MSM and the moderate effect sizes attained by traditional brief behavioral interventions to date, the HIV prevention agenda requires a shift toward improved assessment of psychosocial comorbidities and stronger integration with mental health and substance abuse treatment services. PMID:25501609

  1. Prevalence and predictors of Axis I disorders in a large sample of treatment-seeking victims of sexual abuse and incest

    PubMed Central

    McElroy, Eoin; Shevlin, Mark; Elklit, Ask; Hyland, Philip; Murphy, Siobhan; Murphy, Jamie

    2016-01-01

    Background Childhood sexual abuse (CSA) is a common occurrence and a robust, yet non-specific, predictor of adult psychopathology. While many demographic and abuse factors have been shown to impact this relationship, their common and specific effects remain poorly understood. Objective This study sought to assess the prevalence of Axis I disorders in a large sample of help-seeking victims of sexual trauma, and to examine the common and specific effects of demographic and abuse characteristics across these different diagnoses. Method The participants were attendees at four treatment centres in Denmark that provide psychological therapy for victims of CSA (N=434). Axis I disorders were assessed using the Millon Clinical Multiaxial Inventory-III (MCMI-III). Multivariate logistic regression analysis was used to examine the associations between CSA characteristics (age of onset, duration, number of abusers, number of abusive acts) and 10 adult clinical syndromes. Results There was significant variation in the prevalence of disorders and the abuse characteristics were differentially associated with the outcome variables. Having experienced sexual abuse from more than one perpetrator was the strongest predictor of psychopathology. Conclusions The relationship between CSA and adult psychopathology is complex. Abuse characteristics have both unique and shared effects across different diagnoses. Highlights of the article The prevalence of Axis I disorders were assessed in a large sample of sexual abuse and incest survivors. The impact of demographic and abuse characteristics were also examined. There was significant variation in the prevalence of disorders. Abuse characteristics were differentially associated with the disorders. Abuse from multiple perpetrators was the strongest overall predictor of psychopathology. PMID:27064976

  2. Indirect methods to control population distribution in a large spin system

    NASA Astrophysics Data System (ADS)

    Zhao, Lingfei; Goryachev, Maxim; Bourhill, Jeremy; Tobar, Michael E.

    2017-03-01

    We demonstrate how a large spin system (S=7/2) with the ground and first excited state separated by a seven-photon transition exhibits nonequilibrium thermodynamic properties and how the population distribution may be manipulated using coupling between energy levels. The first method involves non-adiabatic passage through an avoided level crossing controlled with an external DC magnetic field and the resulting Landau–Zener transition. The second method is based on external cavity pumping to a higher energy state hybridised with another state that is two single-photon transitions away from the ground state. The results are confirmed experimentally with a Gd3+ impurity ion ensemble in a YVO4 crystal cooled to 20 mK, which also acts as a microwave photonic whispering gallery mode resonator. Extremely long lifetimes are observed due to the large number of photons required for the transition between the ground and first excited states.

  3. Validation of Blood-Based Assays Using Dried Blood Spots for Use in Large Population Studies

    PubMed Central

    CRIMMINS, EILEEN; KIM, JUNG KI; McCREATH, HEATHER; FAUL, JESSICA; WEIR, DAVID; SEEMAN, TERESA

    2014-01-01

    Assessment of health in large population studies has increasingly incorporated measures of blood-based biomarkers based on the use of dried blood spots (DBS). The validity of DBS assessments made by labs used by large studies is addressed by comparing assay values from DBS collected using conditions similar to those used in the field with values from whole blood samples. The DBS approach generates values that are strongly related to whole blood levels of HbA1c, cystatin C, and C-reactive protein. Assessing lipid levels reliably with DBS appears to be a greater challenge. However, even when DBS values and values from venous blood are highly correlated, they are often on a different scale, and using conventional cutoffs may be misleading. PMID:24784986

  4. Population growth rate and genetic variability of small and large populations of Red flour beetle (Tribolium castaneum) following multigenerational exposure to copper.

    PubMed

    Laskowski, Ryszard; Radwan, Jacek; Kuduk, Katarzyna; Mendrok, Magdalena; Kramarz, Paulina

    2015-07-01

    We reared large (1000 individuals) and small (20 individuals) populations of Tribolium castaneum on diet contaminated with copper in order to determine if the size of a population affects its ability to adapt to adverse environmental conditions. After 10 generations, we used microsatellite markers to estimate and subsequently compare the genetic variability of the copper-treated populations with that of the control populations, which were reared on uncontaminated medium. Additionally, we conducted a full cross-factorial experiment which evaluated the effects of 10 generations of "pre-exposure" to copper on a population's fitness in control and copper-contaminated environments. In order to distinguish results potentially arising from genetic adaptation from those due to non-genetic effects associated to parental exposure to copper, we subjected also F11 generation, originating from parents not exposed to copper, to the same cross-factorial experiment. The effects of long-term exposure to copper depended on population size: the growth rates of small populations that were pre-exposed to copper were inhibited compared to those of small populations reared in uncontaminated environments. Large Cu-exposed populations had a higher growth rate in the F10 generation compared to the control groups, while the growth rate of the F11 generation was unaffected by copper exposure history. The only factor that had a significant effect on genetic variability was population size, but this was to be expected given the large difference in the number of individuals between large and small populations. Neither copper contamination nor its interaction with population size affected the number of microsatellite alleles retained in the F10 generation.

  5. The stellar accretion origin of stellar population gradients in massive galaxies at large radii

    NASA Astrophysics Data System (ADS)

    Hirschmann, Michaela; Naab, Thorsten; Ostriker, Jeremiah P.; Forbes, Duncan A.; Duc, Pierre-Alain; Davé, Romeel; Oser, Ludwig; Karabal, Emin

    2015-05-01

    We investigate the evolution of stellar population gradients from z = 2 to 0 in massive galaxies at large radii (r > 2Reff) using 10 cosmological zoom simulations of haloes with 6 × 1012 M⊙ < Mhalo < 2 × 1013 M⊙. The simulations follow metal cooling and enrichment from SNII, SNIa and asymptotic giant branch winds. We explore the differential impact of an empirical model for galactic winds that reproduces the mass-metallicity relation and its evolution with redshift. At larger radii the galaxies, for both models, become more dominated by stars accreted from satellite galaxies in major and minor mergers. In the wind model, fewer stars are accreted, but they are significantly more metal-poor resulting in steep global metallicity (<∇Zstars> = -0.35 dex dex-1) and colour (e.g. <∇g - r> = -0.13 dex dex-1) gradients in agreement with observations. In contrast, colour and metallicity gradients of the models without winds are inconsistent with observations. Age gradients are in general mildly positive at z = 0 (<∇Agestars> = 0.04 dex dex-1) with significant differences between the models at higher redshift. We demonstrate that for the wind model, stellar accretion is steepening existing in situ metallicity gradients by about 0.2 dex by the present day and helps to match observed gradients of massive early-type galaxies at large radii. Colour and metallicity gradients are significantly steeper for systems which have accreted stars in minor mergers, while galaxies with major mergers have relatively flat gradients, confirming previous results. The effect of stellar migration of in situ formed stars to large radii is discussed. This study highlights the importance of stellar accretion for stellar population properties of massive galaxies at large radii, which can provide important constraints for formation models.

  6. Extreme genetic diversity in asexual grass thrips populations.

    PubMed

    Fontcuberta García-Cuenca, A; Dumas, Z; Schwander, T

    2016-05-01

    The continuous generation of genetic variation has been proposed as one of the main factors explaining the maintenance of sexual reproduction in nature. However, populations of asexual individuals may attain high levels of genetic diversity through within-lineage diversification, replicate transitions to asexuality from sexual ancestors and migration. How these mechanisms affect genetic variation in populations of closely related sexual and asexual taxa can therefore provide insights into the role of genetic diversity for the maintenance of sexual reproduction. Here, we evaluate patterns of intra- and interpopulation genetic diversity in sexual and asexual populations of Aptinothrips rufus grass thrips. Asexual A. rufus populations are found throughout the world, whereas sexual populations appear to be confined to few locations in the Mediterranean region. We found that asexual A. rufus populations are characterized by extremely high levels of genetic diversity, both in comparison with their sexual relatives and in comparison with other asexual species. Migration is extensive among asexual populations over large geographic distances, whereas close sexual populations are strongly isolated from each other. The combination of extensive migration with replicate evolution of asexual lineages, and a past demographic expansion in at least one of them, generated high local clone diversities in A. rufus. These high clone diversities in asexual populations may mimic certain benefits conferred by sex via genetic diversity and could help explain the extreme success of asexual A. rufus populations.

  7. A trade-off between sexual signalling and immune function in a natural population of the drumming wolf spider Hygrolycosa rubrofasciata.

    PubMed

    Ahtiainen, J J; Alatalo, R V; Kortet, R; Rantala, M J

    2005-07-01

    The field of ecological immunology is ultimately seeking to address the question 'Why is there variation in immune function?' Here, we provide experimental evidence that costs of ubiquitous sexual signals are a significant source of variation in immune function. In the mating season, males of the wolf spider Hygrolycosa rubrofasciata drum against dry leaves while wandering around the habitat searching for receptive females. According to a previous study, the male metabolic rate during the drumming increases 22-fold compared to the resting metabolic rate. In the present study, we examined whether investment in costly courtship drumming decreases male immune function in a wild population of H. rubrofasciata. We induced males to increase their drumming rate by introducing females in proximity. As estimates of male immune function, we used lytic activity and encapsulation rate. Lytic activity estimates the concentration of antimicrobial peptides in haemolymph, which have been shown to play an important role in defence against bacteria, viruses and fungi. Encapsulation is an important defence mechanism against nematodes and insect parasitoids, but it also plays a role in defence against viruses. Our results show that males with nonarbitrarily increased investment in drumming rate had considerably lower lytic activities than control males. Also, there was a tendency for males with nonarbitrarily increased investment in drumming rate to have lower encapsulation rates than control males. This study provides experimental evidence for the first time, to our knowledge, that there are direct immunological costs of sexual signalling in natural populations. Therefore, immunological costs of sexual signals may provide significant phenotypic variation to parasite-mediated sexual selection.

  8. Lifestyle and risk of premature sexual activity in a high school population of Seventh-Day Adventists: Valuegenesis 1989.

    PubMed

    Weinbender, M L; Rossignol, A M

    1996-01-01

    In the past 20 years, sexually transmitted diseases (STDs), including AIDS, and the physical, psychological, and economic difficulties associated with unwanted pregnancy have increased steadily among American adolescents. The objective of this study was to evaluate Adventist lifestyle as a modification of popular American culture which reduces the risk of early sexual activity in adolescents and thus also reduces the risk for both STDs and teen pregnancy. The study was based on 8,321 respondents to a questionnaire concerning specific behaviors, beliefs, and attitudes among Seventh-Day Adventist youth attending 58 high schools in North American. Analysis of the data demonstrated that a wide variety of behaviors were associated with premature sexual activity, including previously reported high-risk behaviors such as drug or alcohol use. In addition, several behaviors that are discouraged within Adventist culture, such as going to a movie theater or participating in competitive sports, also were associated with early sexual activity. It is hypothesized that these latter behaviors may predict the emergence of other high-risk behaviors, such as early sexual activity, in both Adventist and popular cultures, and thus may be "transition-marking behaviors" as described by Jessor and Jessor (1975).

  9. Determination of the coenzyme Q10 status in a large Caucasian study population.

    PubMed

    Onur, Simone; Niklowitz, Petra; Fischer, Alexandra; Jacobs, Gunnar; Lieb, Wolfgang; Laudes, Matthias; Menke, Thomas; Döring, Frank

    2015-01-01

    Coenzyme Q10 (CoQ10 ) exists in a reduced (ubiquinol) and an oxidized (ubiquinone) form in all human tissues and functions, amongst others, in the respiratory chain, redox-cycles, and gene expression. As the status of CoQ10 is an important risk factor for several diseases, here we determined the CoQ10 status (ubiquinol, ubiquinone) in a large Caucasian study population (n = 1,911). The study population covers a wide age range (age: 18-83 years, 43.4% men), has information available on more than 10 measured clinical phenotypes, more than 30 diseases (presence vs. absence), about 30 biomarkers, and comprehensive genetic information including whole-genome SNP typing (>891,000 SNPs). The major aim of this long-term resource in CoQ10 research is the comprehensive analysis of the CoQ10 status with respect to integrated health parameters (i.e., fat metabolism, inflammation), disease-related biomarkers (i.e., liver enzymes, marker for heart failure), common diseases (i.e., neuropathy, myocardial infarction), and genetic risk in humans. Based on disease status, biomarkers, and genetic variants, our cohort is also useful to perform Mendelian randomisation approaches. In conclusion, the present study population is a promising resource to gain deeper insight into CoQ10 status in human health and disease.

  10. Large Magellanic Cloud Planetary Nebula Morphology: Probing Stellar Populations and Evolution.

    PubMed

    Stanghellini; Shaw; Balick; Blades

    2000-05-10

    Planetary nebulae (PNe) in the Large Magellanic Cloud (LMC) offer the unique opportunity to study both the population and evolution of low- and intermediate-mass stars, by means of the morphological type of the nebula. Using observations from our LMC PN morphological survey, and including images available in the Hubble Space Telescope Data Archive and published chemical abundances, we find that asymmetry in PNe is strongly correlated with a younger stellar population, as indicated by the abundance of elements that are unaltered by stellar evolution (Ne, Ar, and S). While similar results have been obtained for Galactic PNe, this is the first demonstration of the relationship for extragalactic PNe. We also examine the relation between morphology and abundance of the products of stellar evolution. We found that asymmetric PNe have higher nitrogen and lower carbon abundances than symmetric PNe. Our two main results are broadly consistent with the predictions of stellar evolution if the progenitors of asymmetric PNe have on average larger masses than the progenitors of symmetric PNe. The results bear on the question of formation mechanisms for asymmetric PNe-specifically, that the genesis of PNe structure should relate strongly to the population type, and by inference the mass, of the progenitor star and less strongly on whether the central star is a member of a close binary system.

  11. Spatial and temporal variability modify density dependence in populations of large herbivores.

    PubMed

    Wang, Guiming; Hobbs, N Thompson; Boone, Randall B; Illius, Andrew W; Gordon, Iain J; Gross, John E; Hamlin, Kenneth L

    2006-01-01

    A central challenge in ecology is to understand the interplay of internal and external controls on the growth of populations. We examined the effects of temporal variation in weather and spatial variation in vegetation on the strength of density dependence in populations of large herbivores. We fit three subsets of the model ln(Nt) = a + (1 + b) x ln(N(t-1)) + c x ln(N(t-2)) to five time series of estimates (Nt) of abundance of ungulates in the Rocky Mountains, USA. The strength of density dependence was estimated by the magnitude of the coefficient b. We regressed the estimates of b on indices of temporal heterogeneity in weather and spatial heterogeneity in resources. The 95% posterior intervals of the slopes of these regressions showed that temporal heterogeneity strengthened density-dependent feedbacks to population growth, whereas spatial heterogeneity weakened them. This finding offers the first empirical evidence that density dependence responds in different ways to spatial heterogeneity and temporal heterogeneity.

  12. Absence of population structure across elevational gradients despite large phenotypic variation in mountain chickadees (Poecile gambeli)

    PubMed Central

    Jahner, Joshua P.; Kozlovsky, Dovid Y.; Parchman, Thomas L.; Pravosudov, Vladimir V.

    2017-01-01

    Montane habitats are characterized by predictably rapid heterogeneity along elevational gradients and are useful for investigating the consequences of environmental heterogeneity for local adaptation and population genetic structure. Food-caching mountain chickadees inhabit a continuous elevation gradient in the Sierra Nevada, and birds living at harsher, high elevations have better spatial memory ability and exhibit differences in male song structure and female mate preference compared to birds inhabiting milder, low elevations. While high elevation birds breed, on average, two weeks later than low elevation birds, the extent of gene flow between elevations is unknown. Despite phenotypic variation and indirect evidence for local adaptation, population genetic analyses based on 18 073 single nucleotide polymorphisms across three transects of high and low elevation populations provided no evidence for genetic differentiation. Analyses based on individual genotypes revealed no patterns of clustering, pairwise estimates of genetic differentiation (FST, Nei's D) were very low, and AMOVA revealed no evidence for genetic variation structured by transect or by low and high elevation sites within transects. In addition, we found no consistent evidence for strong parallel allele frequency divergence between low and high elevation sites within the three transects. Large elevation-related phenotypic variation may be maintained by strong selection despite gene flow and future work should focus on the mechanisms underlying such variation.

  13. Artemia parthenogenetica (Branchiopoda: Anostraca) from the Large Aral Sea: Abundance, distribution, population structure and cyst production

    NASA Astrophysics Data System (ADS)

    Arashkevich, Elena G.; Sapozhnikov, P. V.; Soloviov, K. A.; Kudyshkin, T. V.; Zavialov, P. O.

    2009-03-01

    The brine shrimp Artemia parthenogenetica appeared in the Large Aral Sea (Central Asia) in 1998 when mineralization reached 63 ppt. Data on Artemia abundance and biomass, along with temperature and salinity measurements were collected in the western basin during 2002-2006, primarily in the autumn. During the study period, population density grew progressively, both in terms of number, from 250 to 1260 individuals per m 3, and in terms of biomass, from 0.3 to 1.3 g per m 3. In 2005, the population density and spatial distribution in the different parts of the sea (western and eastern basins and strait) was assessed. The horizontal distribution of the Artemia population was uniform in the deep central part of the western basin, although the distribution was quite patchy in the shallow coastal zone. Depth habitat of Artemia was restricted to the upper 20-25 m of depth, as the oxygen depletion and formation of anoxic layer prevented distribution of Artemia to the deeper waters. In autumn, all females reproduced oviparously, with an average clutch size of 30-35 eggs per female. The number of eggs in a clutch was positively correlated with female body length ( r2 = 0.36-0.44).

  14. Epidemiological features of amyotrophic lateral sclerosis in a large clinic-based African American population.

    PubMed

    Kazamel, Mohamed; Cutter, Gary; Claussen, Gwendolyn; Alsharabati, Mohammad; Oh, Shin J; Lu, Liang; King, Peter H

    2013-09-01

    Our objective was to identify the main clinical and epidemiological features of ALS in a large cohort of African American (AA) patients and compare them to Caucasian (CA) patients in a clinic-based population. We retrospectively identified 207 patients who were diagnosed with ALS based on the revised El Escorial criteria (60 AA and 147 CA subjects). Patients were seen in the Neuromuscular Division at the University Medical Center. We compared epidemiological and clinical features of these two groups, focusing on age of onset and diagnosis, clinical presentation and survival. Results showed that AA patients had a significantly younger age of disease onset (55 years vs. 61 years for CA, p = 0.011) and were diagnosed at an earlier age (56 years vs. 62 years, p = 0.012). In younger ALS patients (< 45 years of age), there was a significant difference in gender frequency, with females predominating in the AA population and males in the CA population (p = 0.025). In a multivariable Cox proportional hazard model, survival rates were not different between the groups. In both groups, survival significantly increased with younger age. In conclusion, AA patients presented at an earlier age, but there was no difference in survival compared to CA patients. A gender reversal occurred in younger ALS patients, with AA patients more likely to be female and CA patients more likely to be male.

  15. Voluntary rewards mediate the evolution of pool punishment for maintaining public goods in large populations.

    PubMed

    Sasaki, Tatsuya; Uchida, Satoshi; Chen, Xiaojie

    2015-03-10

    Punishment is a popular tool when governing commons in situations where free riders would otherwise take over. It is well known that sanctioning systems, such as the police and courts, are costly and thus can suffer from those who free ride on other's efforts to maintain the sanctioning systems (second-order free riders). Previous game-theory studies showed that if populations are very large, pool punishment rarely emerges in public good games, even when participation is optional, because of second-order free riders. Here we show that a matching fund for rewarding cooperation leads to the emergence of pool punishment, despite the presence of second-order free riders. We demonstrate that reward funds can pave the way for a transition from a population of free riders to a population of pool punishers. A key factor in promoting the transition is also to reward those who contribute to pool punishment, yet not abstaining from participation. Reward funds eventually vanish in raising pool punishment, which is sustainable by punishing the second-order free riders. This suggests that considering the interdependence of reward and punishment may help to better understand the origins and transitions of social norms and institutions.

  16. Voluntary rewards mediate the evolution of pool punishment for maintaining public goods in large populations

    NASA Astrophysics Data System (ADS)

    Sasaki, Tatsuya; Uchida, Satoshi; Chen, Xiaojie

    2015-03-01

    Punishment is a popular tool when governing commons in situations where free riders would otherwise take over. It is well known that sanctioning systems, such as the police and courts, are costly and thus can suffer from those who free ride on other's efforts to maintain the sanctioning systems (second-order free riders). Previous game-theory studies showed that if populations are very large, pool punishment rarely emerges in public good games, even when participation is optional, because of second-order free riders. Here we show that a matching fund for rewarding cooperation leads to the emergence of pool punishment, despite the presence of second-order free riders. We demonstrate that reward funds can pave the way for a transition from a population of free riders to a population of pool punishers. A key factor in promoting the transition is also to reward those who contribute to pool punishment, yet not abstaining from participation. Reward funds eventually vanish in raising pool punishment, which is sustainable by punishing the second-order free riders. This suggests that considering the interdependence of reward and punishment may help to better understand the origins and transitions of social norms and institutions.

  17. Individual quality, early-life conditions, and reproductive success in contrasted populations of large herbivores.

    PubMed

    Hamel, Sandra; Gaillard, Jean-Michel; Festa-Bianchet, Marco; Côté, Steeve D

    2009-07-01

    Variations among individuals in phenotypic quality and fitness often confound analyses of life-history strategies assessed at the population level. We used detailed long-term data from three populations of large herbivores with generation times ranging from four to nine years to quantify heterogeneity in individual quality among females, and to assess its influence on mean annual reproductive success over the lifetime (MRS). We also determined how environmental conditions in early life shaped individual quality and tested A. Lomnicki's hypothesis that variance in individual quality should increase when environmental conditions deteriorate. Using multivariate analyses (PCA), we identified one (in sheep and deer) or two (in goats) covariations among life-history traits (longevity, success in the last breeding opportunity, adult mass, and social rank) as indexes of individual quality that positively influenced MRS of females. Individual quality was reduced by unfavorable weather, low resource availability, and high population density in the year of birth. Early-life conditions accounted for 35-55% of variation in individual quality. In roe deer, we found greater variance in individual quality for cohorts born under unfavorable conditions as opposed to favorable ones, but the opposite was found in bighorn sheep and mountain goats. Our results demonstrate that heterogeneity in female quality can originate from environmental conditions in early life and can markedly influence the fitness of females in species located at different positions along the slow-fast continuum of life-history strategies.

  18. Which processes shape stellar population gradients of massive galaxies at large radii?

    NASA Astrophysics Data System (ADS)

    Hirschmann, Michaela

    2016-08-01

    We investigate the differential impact of physical mechanisms, mergers (stellar accretion) and internal energetic phenomena, on the evolution of stellar population gradients in massive, present-day galaxies employing a set of high-resolution, cosmological zoom simulations. We demonstrate that negative metallicity and color gradients at large radii (>2Reff) originate from the accretion of metal-poor stellar systems. At larger radii, galaxies become typically more dominated by stars accreted from satellite galaxies in major and minor mergers. However, only strong galactic winds can sufficiently reduce the metallicity content of the accreted stars to realistically steepen the outer metallicity and colour gradients in agreement with present-day observations. In contrast, the gradients of the models without winds are inconsistent with observations (too flat). In the wind model, colour and metallicity gradients are significantly steeper for systems which have accreted stars in minor mergers, while galaxies with major mergers have relatively flat gradients, confirming previous results. This analysis greatly highlights the importance of both energetic processes and merger events for stellar population properties of massive galaxies at large radii. Our results are expected to significantly contribute to the interpretation of current and up-coming IFU surveys (like MaNGA and Califa), which in turn can help to better constrain still uncertain models for energetic processes in simulations.

  19. Theory of population coupling and applications to describe high order correlations in large populations of interacting neurons

    NASA Astrophysics Data System (ADS)

    Huang, Haiping

    2017-03-01

    To understand the collective spiking activity in neuronal populations, it is essential to reveal basic circuit variables responsible for these emergent functional states. Here, I develop a mean field theory for the population coupling recently proposed in the studies of the visual cortex of mouse and monkey, relating the individual neuron activity to the population activity, and extend the original form to the second order, relating neuron-pair’s activity to the population activity, to explain the high order correlations observed in the neural data. I test the computational framework on the salamander retinal data and the cortical spiking data of behaving rats. For the retinal data, the original form of population coupling and its advanced form can explain a significant fraction of two-cell correlations and three-cell correlations, respectively. For the cortical data, the performance becomes much better, and the second order population coupling reveals non-local effects in local cortical circuits.

  20. Characterization of mitochondrial haplogroups in a large population-based sample from the United States.

    PubMed

    Mitchell, Sabrina L; Goodloe, Robert; Brown-Gentry, Kristin; Pendergrass, Sarah A; Murdock, Deborah G; Crawford, Dana C

    2014-07-01

    Mitochondrial DNA (mtDNA) haplogroups are valuable for investigations in forensic science, molecular anthropology, and human genetics. In this study, we developed a custom panel of 61 mtDNA markers for high-throughput classification of European, African, and Native American/Asian mitochondrial haplogroup lineages. Using these mtDNA markers, we constructed a mitochondrial haplogroup classification tree and classified 18,832 participants from the National Health and Nutrition Examination Surveys (NHANES). To our knowledge, this is the largest study to date characterizing mitochondrial haplogroups in a population-based sample from the United States, and the first study characterizing mitochondrial haplogroup distributions in self-identified Mexican Americans separately from Hispanic Americans of other descent. We observed clear differences in the distribution of maternal genetic ancestry consistent with proposed admixture models for these subpopulations, underscoring the genetic heterogeneity of the United States Hispanic population. The mitochondrial haplogroup distributions in the other self-identified racial/ethnic groups within NHANES were largely comparable to previous studies. Mitochondrial haplogroup classification was highly concordant with self-identified race/ethnicity (SIRE) in non-Hispanic whites (94.8 %), but was considerably lower in admixed populations including non-Hispanic blacks (88.3 %), Mexican Americans (81.8 %), and other Hispanics (61.6 %), suggesting SIRE does not accurately reflect maternal genetic ancestry, particularly in populations with greater proportions of admixture. Thus, it is important to consider inconsistencies between SIRE and genetic ancestry when performing genetic association studies. The mitochondrial haplogroup data that we have generated, coupled with the epidemiologic variables in NHANES, is a valuable resource for future studies investigating the contribution of mtDNA variation to human health and disease.

  1. Reproductive and resource benefits to large female body size in a mammal with female-biased sexual size dimorphism

    SciTech Connect

    Fokidis, H.B., T.S. Risch and T.C. Glenn

    2007-01-01

    Factors underlying the evolution of female-biased sexual size dimorphism in mammals are poorly understood. In an effort to better understand these factors we tested whether larger female southern flying squirrels, Glaucomys volans, gained reproductive advantages (larger litters or more male mates) and direct resource benefits, such as larger home ranges or access to more food (i.e. mast-producing trees). As dimorphism can vary with age in precocial breeding species, we compared females during their first reproduction and during a subsequent breeding attempt. Females were not significantly larger or heavier than males at first reproduction, but became about 7% heavier and 22% larger than males at subsequent breeding. Larger females produced larger litters and had home ranges containing a greater proportion of upland hardwood trees. Female body size was not associated with either multiple male mating or home range size, but females with larger home ranges had higher indexes of body condition. Females in precocial breeding flying squirrels initiate reproduction before sexual size dimorphism is evident, and thus, may be allocating resources to both reproduction and growth simultaneously, or delaying growth entirely. Larger females produce more pups and have access to more food resources. Thus, selection for increased female size may partly explain how female-biased sexual size dimorphism is maintained in this species.

  2. Seed Population in Large Solar Energetic Particle Events and the Twin-CME Scenario

    NASA Astrophysics Data System (ADS)

    Ding, Liu-Guan; Li, Gang; Le, Gui-Ming; Gu, Bin; Cao, Xin-Xin

    2015-10-01

    It has recently been suggested that large solar energetic particle (SEP) events are often caused by twin coronal mass ejections (CMEs). In the twin-CME scenario, the preceding CME provides both an enhanced turbulence level and enhanced seed population at the main CME-driven shock. In this work, we study the effect of the preceding CMEs on the seed population. We examine event-integrated abundance of iron to oxygen ratio (Fe/O) at energies above 25 MeV/nuc for large SEP events in solar cycle 23. We find that the Fe/O ratio (normalized to the reference coronal value of 0.134) ≤2.0 for almost all single-CME events and these events tend to have smaller peak intensities. In comparison, the Fe/O ratio of twin-CME events scatters in a larger range, reaching as high as 8, suggesting the presence of flare material from perhaps preceding flares. For extremely large SEP events with peak intensities above 1000 pfu, the Fe/O ratios drop below 2, indicating that the seed particles are dominated by coronal material rather than flare material in these extreme events. The Fe/O ratios of ground level enhancement (GLE) events, which are all twin-CME events, scatter in a broad range. For a given Fe/O ratio, GLE events tend to have larger peak intensities than non-GLE events. Using velocity dispersion analysis, we find that GLE events have lower solar particle release heights than non-GLE events, agreeing with earlier results by Reames.

  3. Sexual Difficulties

    MedlinePlus

    ... and conditions Caregiving Wellness Staying active Mental health Sexual health Sexual difficulties Protecting yourself Safety and abuse Falls ... updates. Enter email address Submit Home > Healthy Aging > Sexual health Healthy Aging Sexual difficulties Learn more about men's ...

  4. Rapid assessment of drug use and sexual HIV risk patterns among vulnerable drug-using populations in Cape Town, Durban and Pretoria, South Africa.

    PubMed

    Parry, Charles; Petersen, Petal; Carney, Tara; Dewing, Sarah; Needle, Richard

    2008-09-01

    This exploratory study examines the links between drug use and high-risk sexual practices and HIV in vulnerable drug-using populations in South Africa, including commercial sex workers (CSWs), men who have sex with men (MSM), injecting drug users (IDUs) and non-injecting drug users who are not CSWs or MSM (NIDUs). A rapid assessment ethnographic study was undertaken using observation, mapping, key informant interviews and focus groups in known 'hotspots' for drug use and sexual risk in Cape Town, Durban and Pretoria. Key informant (KI) and focus group interviews involved drug users and service providers. Purposeful snowball sampling and street intercepts were used to recruit drug users. Outcome measures included drug-related sexual HIV risk behaviour, and risk behaviour related to injection drug use, as well as issues related to service use. HIV testing of drug-using KIs was conducted using the SmartCheck Rapid HIV-1 Antibody Test. Non-injection drug use (mainly cannabis, methaqualone, crack cocaine and crystal methamphetamine) and injection drug use (mainly heroin) was occurring in these cities. Drug users report selling sex for money to buy drugs, and CSWs used drugs before, during and after sex. Most (70%) of the drug-using KIs offered HIV testing accepted and 28% were positive, with rates highest among CSWs and MSM. IDUs reported engaging in needle sharing and needle disposal practices that put them and others at risk for contracting HIV. There was a widespread lack of awareness about where to access HIV treatment and preventive services, and numerous barriers to accessing appropriate HIV and drug-intervention services were reported. Multiple risk behaviours of vulnerable populations and lack of access to HIV prevention services could accelerate the diffusion of HIV. Targeted interventions could play an important role in limiting the spread of HIV in and through these under-reached and vulnerable populations.

  5. Screening and management practices for renal disease in the HIV-positive patient population of an inner metropolitan sexual health service.

    PubMed

    Kakar, Sheena; Drak, Douglas; Amin, Tahiya; Cheung, Jason; O'Connor, Catherine C; Gracey, David M

    2017-02-01

    Renal disease is an important and commonly encountered co-morbidity in HIV infection. Despite this, few data are available concerning renal disease in this patient group. A retrospective review was conducted of all HIV-positive patients of an inner metropolitan sexual health service who attended from 1 August 2013 to 31 July 2014 for HIV management. One hundred eighty-eight HIV-positive patients attended the clinic during the study period. The majority were male (96%), Caucasian (70%) and 30-39 years of age (37%). There was a high prevalence of renal risk factors in the population, including potentially nephrotoxic antiretroviral therapy (61%), smoking (38%), hypertension (12%), dyslipidemia (11%) and hepatitis C co-infection (7%). In the previous year, measurements of estimated glomerular filtration rate were performed in all patients, but measurements of lipid profiles, urinary protein and serum phosphate were performed within the last year in only 48%, 33% and 30% of patients, respectively. These are the first comprehensive data regarding renal disease, associated risk factors and screening and management practices in the HIV-positive patient population of a specialized sexual health service in Australia. This patient population demonstrates a particularly high prevalence of risk factors for renal disease. Despite this, screening investigations were not performed as recommended. This represents a potential area to improve patient care.

  6. A Washington Photometric Survey of the Large Magellanic Cloud Field Star Population

    NASA Astrophysics Data System (ADS)

    Piatti, Andrés E.; Geisler, Doug; Mateluna, Renee

    2012-10-01

    We present photometry for an unprecedented database of some 5.5 million stars distributed throughout the Large Magellanic Cloud main body, from 21 fields covering a total area of 7.6 deg2, obtained from Washington CT 1 T 2 CTIO 4 m MOSAIC data. Extensive artificial star tests over the whole mosaic image data set and the observed behavior of the photometric errors with magnitude demonstrate the accuracy of the morphology and clearly delineate the position of the main features in the color-magnitude diagrams (CMDs). The representative T 1(MS TO) mags are on average ~0.5 mag brighter than the T 1 mags for the 100% completeness level of the respective field, allowing us to derive an accurate age estimate. We have analyzed the CMD Hess diagrams and used the peaks in star counts at the main sequence turnoff and red clump (RC) locations to age date the most dominant sub-population (or "representative" population) in the stellar population mix. The metallicity of this representative population is estimated from the locus of the most populous red giant branch track. We use these results to derive age and metallicity estimates for all of our fields. The analyzed fields span age and metallicity ranges covering most of the galaxy's lifetime and chemical enrichment, i.e., ages and metallicities between ~1 and 13 Gyr and ~-0.2 and -1.2 dex, respectively. We show that the dispersions associated with the mean ages and metallicities represent in general a satisfactory estimate of the age/metallicity spread (~1-3 Gyr/0.2-0.3 dex), although a few subfields have a slightly larger age/metallicity spread. Finally, we revisit the study of the vertical structure (VS) phenomenon, a striking feature composed of stars that extend from the bottom, bluest end of the RC to ~0.45 mag fainter. We confirm that the VS phenomenon is not clearly seen in most of the studied fields and suggest that its occurrence is linked to some other condition(s) in addition to the appropriate age, metallicity, and

  7. Narrative constructions of sexual violence as told by female rape survivors in three populations of the southwestern United States: scripts of coercion, scripts of consent.

    PubMed

    Bletzer, Keith V; Koss, Mary P

    2004-01-01

    There is a growing literature on the narrative construction of rape as sexual violence. This is puzzling, since, in certain contexts, violence may stifle narrative production. Researchers of atrocities, for example, propose that the experience of recurring terror disrupts narrative cohesion in reporting lived trauma. Genocidal horror occurs in the context of communities and ethnic groups. Our rape survival data from women of three populations in the southwestern United States reflect traumas of sexual violence against women, experienced within everyday lives. From interviews with 62 female rape survivors, we (1) identify narrative conventions and linguistic devices to show how these women structure accounts of sexual assault that reflect their cultural background; (2) contrast scripts of coercion and consent; (3) examine how the way in which these women describe the coercive actions of the perpetrator(s) contradicts the assumptions of legal discourse; and (4) discuss the narrative production of several women in abusive relationships and compare it to the narrative production (or lack thereof) of persons who experience state-engineered terror.

  8. Prevention of Sexually Transmitted Infections in Different Populations: A Review of Behaviourally Effective and Cost-Effective Interventions.

    ERIC Educational Resources Information Center

    McKay, Alexander

    2000-01-01

    Reviews literature supporting the development and implementation of effective human immunodeficiency virus/sexually transmitted disease behavioral interventions for adolescents, street youth, clinic patients, women, heterosexually active men, men who have sex with men, and communities, discussing favorable behavioral outcomes, describing…

  9. Leveraging domain knowledge to facilitate visual exploration of large population datasets.

    PubMed

    Hsu, William; Bui, Alex A T

    2013-01-01

    Observational patient data provides an unprecedented opportunity to gleam new insights into diseases and assess patient quality of care, but a challenge lies in matching our ability to collect data with a comparable ability to understand and apply this information. Visual analytic techniques are promising as they permit the exploration and manipulation of complex datasets through a graphical user interface. Nevertheless, current visualization tools rely on users to manually configure which aspects of the dataset are shown and how they are presented. In this paper, we describe an approach that utilizes characteristics of the data and domain knowledge to assist users with summarizing the information space of a large population. We present a representation that captures contextual information about the data and constructs that operate on this information to tailor the data's presentation. We describe a use case of this approach in exploring a claims dataset of individuals with spinal dysraphism.

  10. A phenomenological approach to the simulation of metabolism and proliferation dynamics of large tumour cell populations

    NASA Astrophysics Data System (ADS)

    Chignola, Roberto; Milotti, Edoardo

    2005-03-01

    A major goal of modern computational biology is to simulate the collective behaviour of large cell populations starting from the intricate web of molecular interactions occurring at the microscopic level. In this paper we describe a simplified model of cell metabolism, growth and proliferation, suitable for inclusion in a multicell simulator, now under development (Chignola R and Milotti E 2004 Physica A 338 261-6). Nutrients regulate the proliferation dynamics of tumour cells which adapt their behaviour to respond to changes in the biochemical composition of the environment. This modelling of nutrient metabolism and cell cycle at a mesoscopic scale level leads to a continuous flow of information between the two disparate spatiotemporal scales of molecular and cellular dynamics that can be simulated with modern computers and tested experimentally.

  11. Comparison of large crater and multiringed basin populations on Mars, Mercury, and the moon

    NASA Technical Reports Server (NTRS)

    Malin, M. C.

    1976-01-01

    The maximum regional areal densities of large impact craters on Mars, Mercury, and the moon appear to be inversely proportional to the surface areas of the planets. This would not be expected if the objects impacting the planetary surfaces came from common sources and were moving with high velocities relative to the planets; rather, a uniform areal density would be anticipated. Another way of stating the observation is that each planet was bombarded by the same number of objects. Two speculative explanations for the observation are that: (1) all planets underwent a uniform bombardment but were resurfaced by processes proportional to planetary surface area, or (2) equally populated families of objects, moving about the sun in orbits similar to those of the planets, were independently depopulated by the respective planets.

  12. Canadian fishery closures provide a large-scale test of the impact of gillnet bycatch on seabird populations.

    PubMed

    Regular, Paul; Montevecchi, William; Hedd, April; Robertson, Gregory; Wilhelm, Sabina

    2013-08-23

    In 1992, the eastern Canadian gillnet fisheries for northern cod and Atlantic salmon were largely closed. These large-scale fishery closures resulted in the removal of tens of thousands of gillnets known to inflict high levels of seabird mortality. We used this unprecedented opportunity to test the effects of gillnet removal on seabird populations. Consistent with predictions, we show that the breeding populations of divers (auks, gannets; susceptible to gillnet bycatch) have increased from pre-closure levels, whereas the populations of scavenging surface-feeders (gulls; low vulnerability to gillnet bycatch but susceptible to removal of fisheries discards) have decreased. Using the most complete series of seabird census data for the species most vulnerable to bycatch, we demonstrate a positive population response of common murres to reduction in gillnet fishing within its foraging range. These findings support the widespread but seldom documented contention that fisheries bycatch negatively impacts populations of non-target large vertebrates.

  13. Mass-loss From Evolved Stellar Populations In The Large Magellanic Cloud

    NASA Astrophysics Data System (ADS)

    Riebel, David

    2012-01-01

    I have conducted a study of a sample of 30,000 evolved stars in the Large Magellanic Cloud (LMC) and 6,000 in the Small Magellanic Cloud (SMC), covering their variability, mass-loss properties, and chemistry. The initial stages of of my thesis work focused on the infrared variability of Asymptotic Giant Branch (AGB) stars in the LMC. I determined the period-luminosity (P-L) relations for 6 separate sequences of 30,000 evolved star candidates at 8 wavelengths, as a function of photometrically assigned chemistry, and showed that the P-L relations are different for different chemical populations (O-rich or C-rich). I also present results from the Grid of Red supergiant and Asymptotic giant branch star ModelS (GRAMS) radiative transfer (RT) model grid applied to the evolved stellar population of the LMC. GRAMS is a pre-computed grid of RT models of RSG and AGB stars and surrounding circumstellar dust. Best-fit models are determined based on 12 bands of photometry from the optical to the mid-infrared. Using a pre-computed grid, I can present the first reasonably detailed radiative transfer modeling for tens of thousands of stars, allowing me to make statistically accurate estimations of the carbon-star luminosity function and the global dust mass return to the interstellar medium from AGB stars, both key parameters for stellar population synthesis models to reproduce. In the SAGE-Var program, I used the warm Spitzer mission to take 4 additional epochs of observations of 7500 AGB stars in the LMC and SMC. These epochs, combined with existing data, enable me to derive mean fluxes at 3.6 and 4.5 microns, that will be used for tighter constraints for GRAMS, which is currently limited by the variability induced error on the photometry. This work is support by NASA NAG5-12595 and Spitzer contract 1415784.

  14. Platelet serotonin transporter (5HTt): physiological influences on kinetic characteristics in a large human population.

    PubMed

    Banović, Miroslav; Bordukalo-Niksić, Tatjana; Balija, Melita; Cicin-Sain, Lipa; Jernej, Branimir

    2010-01-01

    The present study had two goals: first, to give a detailed description of a reliable method for full kinetic analysis of serotonin transporter (5HTt) on the membrane of human platelets, and second, as a main issue, to report on physiological influences on kinetic characteristics of this transmembrane transport on a large population of healthy individuals. Full kinetic analyses of platelet serotonin uptake were performed on 334 blood donors of both sexes by the use of 14C-radioisotopic method, which was first optimized according to assumptions of enzyme kinetic analyses, with regard to platelet concentration, duration of uptake, concentration of substrate as well as important technical parameters (underpressure of filtration, blanks, incubating temperature, etc). Kinetic parameters of platelet serotonin uptake in the whole population were for V(max): 142 +/- 25.3 pmol 5HT/10(8) platelets/minute and for K(m): 0.404 +/- 0.089 microM 5HT. Besides the report on kinetic values of 5HT transporter protein, we have also described major physiological influences on the mentioned parameters, V(max), K(m) and their derivative, V(max)/K(m) (transporter efficiency): range and frequency distribution of normal values, intraindividual stability over time, lack of age influence, gender dependence and seasonal variations. The report on kinetic values and main physiological influences on platelet serotonin transport kinetics, obtained by the use of thoroughly reassessed methodology, and on by far the largest human population studied until now, offers a reliable frame of reference for pathophysiological studies of this parameter in various clinical fields.

  15. Sexual size dimorphism in anurans.

    PubMed Central

    Monnet, Jean-Matthieu; Cherry, Michael I

    2002-01-01

    Several hypotheses have been proposed to explain the direction and extent of sexual size dimorphism in anurans (in which males are usually smaller than females) as a result of sexual selection. Here, we present an analysis to test the hypothesis that sexual dimorphism in anurans is largely a function of differences between the sexes in life-history strategies. Morphological and demographic data for anurans were collected from the literature, and the mean size and age in each sex were calculated for 51 populations, across 30 species and eight genera. Comparisons across 14 Rana species, eight Bufo species and across the genera showed a highly significant relationship between size dimorphism, measured using the female-male size ratio, and mean female-male age difference. A comparison of a subset of 17 of these species for which phylogenetic information was available, using the method of independent contrasts, yielded a similar result. These results indicate that most of the variation in size dimorphism in the anura can be explained in terms of differences in the age structure between the sexes in breeding populations. If sexual selection has an effect on size dimorphism in anurans, it is likely to be only a secondary one. PMID:12495496

  16. Circadian analysis of large human populations: inferences from the power grid.

    PubMed

    Stowie, Adam C; Amicarelli, Mario J; Crosier, Caitlin J; Mymko, Ryan; Glass, J David

    2015-03-01

    Few, if any studies have focused on the daily rhythmic nature of modern industrialized populations. The present study utilized real-time load data from the U.S. Pacific Northwest electrical power grid as a reflection of human operative household activity. This approach involved actigraphic analyses of continuously streaming internet data (provided in 5 min bins) from a human subject pool of approximately 43 million primarily residential users. Rhythm analyses reveal striking seasonal and intra-week differences in human activity patterns, largely devoid of manufacturing and automated load interference. Length of the diurnal activity period (alpha) is longer during the spring than the summer (16.64 h versus 15.98 h, respectively; p < 0.01). As expected, significantly more activity occurs in the solar dark phase during the winter than during the summer (6.29 h versus 2.03 h, respectively; p < 0.01). Interestingly, throughout the year a "weekend effect" is evident, where morning activity onset occurs approximately 1 h later than during the work week (5:54 am versus 6:52 am, respectively; p < 0.01). This indicates a general phase-delaying response to the absence of job-related or other weekday morning arousal cues, substantiating a preference or need to sleep longer on weekends. Finally, a shift in onset time can be seen during the transition to Day Light Saving Time, but not the transition back to Standard Time. The use of grid power load as a means for human actimetry assessment thus offers new insights into the collective diurnal activity patterns of large human populations.

  17. Ab initio phenomenological simulation of the growth of large tumor cell populations

    NASA Astrophysics Data System (ADS)

    Chignola, Roberto; DelFabbro, Alessio; Dalla Pellegrina, Chiara; Milotti, Edoardo

    2007-06-01

    In a previous paper we have introduced a phenomenological model of cell metabolism and of the cell cycle to simulate the behavior of large tumor cell populations (Chignola and Milotti 2005 Phys. Biol. 2 8). Here we describe a refined and extended version of the model that includes some of the complex interactions between cells and their surrounding environment. The present version takes into consideration several additional energy-consuming biochemical pathways such as protein and DNA synthesis, the tuning of extracellular pH and of the cell membrane potential. The control of the cell cycle, which was previously modeled by means of ad hoc thresholds, has been directly addressed here by considering checkpoints from proteins that act as targets for phosphorylation on multiple sites. As simulated cells grow, they can now modify the chemical composition of the surrounding environment which in turn acts as a feedback mechanism to tune cell metabolism and hence cell proliferation: in this way we obtain growth curves that match quite well those observed in vitro with human leukemia cell lines. The model is strongly constrained and returns results that can be directly compared with actual experiments, because it uses parameter values in narrow ranges estimated from experimental data, and in perspective we hope to utilize it to develop in silico studies of the growth of very large tumor cell populations (106 cells or more) and to support experimental research. In particular, the program is used here to make predictions on the behavior of cells grown in a glucose-poor medium: these predictions are confirmed by experimental observation.

  18. Fundamental form of a population TCP model in the limit of large heterogeneity.

    PubMed

    Carlone, Marco C; Warkentin, Brad; Stavrev, Pavel; Fallone, B Gino

    2006-06-01

    A population tumor control probability (TCP) model for fractionated external beam radiotherapy, based on Poisson statistics and in the limit of large parameter heterogeneity, is studied. A reduction of a general eight-parameter TCP equation, which incorporates heterogeneity in parameters characterizing linear-quadratic radiosensitivity, repopulation, and clonogen number, to an equation with four parameters is obtained. The four parameters represent the mean and standard deviation for both clonogen number and a generalized radiosensitivity that includes linear-quadratic and repopulation descriptors. Further, owing to parameter inter-relationship, it is possible to express these four parameters as three ratios of parameters in the large heterogeneity limit. These ratios can be directly linked to two defining features of the TCP dose response: D50 and gamma50. In the general case, the TCP model can be written in terms of D50, gamma50 and a third parameter indicating the ratio of the levels of heterogeneity in clonogen number and generalized radiosensitivity; however, the third parameter is unnecessary when either of these two sources of heterogeneity is dominant. It is shown that heterogeneity in clonogen number will have little impact on the TCP formula for clinical scenarios, and thus it will generally be the case that the fundamental form of the Poisson-based population TCP model can be specified completely in terms of D50 and gamma50: TCP= 1/2 erfc[square root of pi(gamma50)(D50/D-1)]. This implies that limited radiobiological information can be determined by the analysis of dose response data: information about parameter ratios can be ascertained, but knowledge of absolute values for the fundamental radiobiological parameters will require independent auxiliary measurements.

  19. Factor analysis of the Hospital Anxiety and Depression Scale from a large cancer population.

    PubMed

    Smith, Adam B; Selby, Peter J; Velikova, Galina; Stark, Dan; Wright, E Penny; Gould, Ann; Cull, Ann

    2002-06-01

    The Hospital Anxiety and Depression Scale (HADS) is widely used as a tool for assessing psychological distress in patients and non-clinical groups. Previous studies have demonstrated conflicting results regarding the factor structure of the questionnaire for different groups of patients, and the general population. This study investigated the factor structure of the HADS in a large heterogeneous cancer population of 1474 patients. It also sought to investigate emerging evidence that the HADS conforms to the tripartite model of anxiety and depression (Clark & Watson, 1993), and to test the proposal that detection rates for clinical cases of anxiety and depression could be enhanced by partialling out the effects of higher order factors from the HADS (Dunbar et al., 2000). The results demonstrated a two-factor structure corresponding to the Anxiety and Depression subscales of the questionnaire. The factor structure remained stable for different subgroups of the sample, for males and females, as well as for different age groups, and a subgroup of metastatic cancer patients. The two factors were highly correlated (r =.52) and subsequent secondary factor analyses demonstrated a single higher order factor corresponding to psychological distress or negative affectivity. We concluded that the HADS comprises two factors corresponding to anhedonia and autonomic anxiety, which share a common variance with a primary factor namely psychological distress, and that the subscales of the HADS, rather than the residual scores (e.g. Dunbar et al., 2000) were more effective at detecting clinical cases of anxiety and depression.

  20. Did Large-Scale Vaccination Drive Changes in the Circulating Rotavirus Population in Belgium?

    PubMed

    Pitzer, Virginia E; Bilcke, Joke; Heylen, Elisabeth; Crawford, Forrest W; Callens, Michael; De Smet, Frank; Van Ranst, Marc; Zeller, Mark; Matthijnssens, Jelle

    2015-12-21

    Vaccination can place selective pressures on viral populations, leading to changes in the distribution of strains as viruses evolve to escape immunity from the vaccine. Vaccine-driven strain replacement is a major concern after nationwide rotavirus vaccine introductions. However, the distribution of the predominant rotavirus genotypes varies from year to year in the absence of vaccination, making it difficult to determine what changes can be attributed to the vaccines. To gain insight in the underlying dynamics driving changes in the rotavirus population, we fitted a hierarchy of mathematical models to national and local genotype-specific hospitalization data from Belgium, where large-scale vaccination was introduced in 2006. We estimated that natural- and vaccine-derived immunity was strongest against completely homotypic strains and weakest against fully heterotypic strains, with an intermediate immunity amongst partially heterotypic strains. The predominance of G2P[4] infections in Belgium after vaccine introduction can be explained by a combination of natural genotype fluctuations and weaker natural and vaccine-induced immunity against infection with strains heterotypic to the vaccine, in the absence of significant variation in strain-specific vaccine effectiveness against disease. However, the incidence of rotavirus gastroenteritis is predicted to remain low despite vaccine-driven changes in the distribution of genotypes.

  1. The characteristics of large bowel cancer in the low-risk black population of the Witwatersrand.

    PubMed

    Boytchev, H; Marcovic, S; Oettle, G J

    1999-12-01

    Sporadic colorectal cancer may follow a different pathogenic pathway in low-risk populations. The black population of the Witwatersrand has been urbanized for a long time, and has a westernized lifestyle, but colorectal cancer is still infrequent. This study aimed to define the characteristics of the disease in this group. All histologically proven large bowel cancers arising in blacks resident in the Witwatersrand in 1991 and 1996 were extracted from the registry records. Mean age was 54.3 years (range 16-90 years); 6% occurred before 30 years and 22% before 40 years. Male:female ratio was 1.32:1. Over three-quarters of the tumours arose in the rectum and sigmoid; there was no evidence of a right-sided preponderance. More than half the cases were advanced at presentation, and nearly one third were mucinous or signet ring on pathological assessment. Associated adenomata were rare (5.2%), suggesting a different pathogenic pathway from the classical adenoma-carcinoma sequence.

  2. Searching for large genomic rearrangements of the BRCA1 gene in a Nigerian population.

    PubMed

    Zhang, Jing; Fackenthal, James D; Huo, Dezheng; Zheng, Yonglan; Olopade, Olufunmilayo I

    2010-11-01

    BRCA1/2 germline mutations predispose to breast and ovarian cancer. Large genomic rearrangements (LGRs) have widened the mutational spectrum of the BRCA1 gene, but the frequencies vary in different populations. In this study, we want to determine the spectrum of LGRs in BRCA1 gene in Nigerian breast cancer patients. The multiplex ligation-dependent probe amplification (MLPA) assay was used to screen BRCA1 rearrangements in 352 patients who previously tested negative for BRCA1 and BRCA2 point mutations and small insertions/deletions. Positive MLPA result was confirmed and located by long-range PCR. The breakpoints of the candidate rearrangement were characterized by sequencing. A novel deletion of BRCA1 exon 21 (c.5277 + 480_5332 + 672del) was detected in 1 out of 352 Nigerian breast cancer patients (0.3% occurrence frequency). Further analysis of breakpoints revealed that the deletion involves two Alu-elements: one AluSg in intron 20 and the AluY in intron 21. These data suggest that while BRCA1 genomic rearrangement exists, they do not contribute significantly to BRCA1-associated risk in the Nigerian population.

  3. Genital abnormalities in early childhood in sexual homicide perpetrators.

    PubMed

    Rettenberger, Martin; Hill, Andreas; Dekker, Arne; Berner, Wolfgang; Briken, Peer

    2013-04-01

    INTRODUCTION.: The present study investigates the relevance of genital abnormalities (GA) like cryptorchidism, hypospadias, and phimosis usually diagnosed in early childhood for the development of psychosexual problems and deficits in a sample of N = 163 convicted sexual homicide perpetrators. AIMS.: The first aim was to investigate the prevalence of early childhood GA in a sample of sexual homicide perpetrators. The second was to explore differences in the psychosexual development of participants with GA in early childhood compared with those without GA. It was expected that offenders with GA show specific problems in their psychosexual development compared with offenders without GA. METHODS.: The data for the present study were obtained by reanalyzing an existing database derived from a large-scale research project about sexual homicide. Using a predominantly exploratory design we, therefore, divided the total sample into two subgroups (with vs. without indicators of GA). MAIN OUTCOME MEASURES.: Main outcome measures were the number of sexual homicide perpetrators showing GA in early childhood and the differences of subjects with and without GA with regard to their psychosexual development (i.e., according to sexual deviant interests or sexual dysfunctions). RESULTS.: The prevalence of GA is substantially higher in this sample than epidemiological studies indicated in the normal population. This result provided first support for the importance of GA in the population of sexual homicide perpetrators. Further analyses indicate significant differences between both subgroups: Offenders with GA in early childhood showed indicators for more sexual dysfunctions (e.g., erectile dysfunction) in adulthood and a distinct tendency of more masochistic sexual interests. CONCLUSION.: Even if the exploratory design of the present investigation allows no causal conclusions between GA and sexual homicide offenses, the result provided support for the relevance of early

  4. Prevalence of metabolic syndrome-related disorders in a large adult population in Turkey

    PubMed Central

    Sanisoglu, S Yavuz; Oktenli, Cagatay; Hasimi, Adnan; Yokusoglu, Mehmet; Ugurlu, Mehmet

    2006-01-01

    Background There are few existing large population studies on the epidemiology of metabolic syndrome-related disorders of Turkey. The purpose of this study was to assess the prevalence of metabolic syndrome-related disorders in the Turkish adult population, to address sex, age, educational and geographical differences, and to examine blood pressure, body mass index, fasting blood glucose and serum lipids in Turkey. Methods This study was executed under the population study "The Healthy Nutrition for Healthy Heart Study" conducted between December 2000 and December 2002 by the Health Ministry of Turkey. Overall, 15,468 Caucasian inhabitants aged over 30 were recruited in 14 centers in the seven main different regions of Turkey. The data were analyzed with the Students' t, ANOVA or Chi-Square tests. Results Overall, more than one-third (35.08 %) of the participants was obese. The hypertensive people ratio in the population was 13.66 %, while these ratios for DM and metabolic syndrome were 4.16 % and 17.91 %, respectively. The prevalence of hypertension, metabolic syndrome and obesity were higher in females than males, whereas diabetes mellitus was higher in males than females. The prevalence of metabolic syndrome and related disorders were found to be significantly different across educational attainments for both men and women. The prevalence of hypertension increased with age, while it was remarkable that in the age group of 60–69 years, prevalence of diabetes mellitus and metabolic syndrome reached a peak value and than decreased. For obesity, the peak prevalence occurred in the 50–59 year old group. The prevalence of metabolic syndrome and related disorders were found to be significantly different according to geographical region. Conclusion In conclusion, high prevalence of obesity and metabolic syndrome, particularly among women, is one of the major public health problems in Turkey. Interestingly, obesity prevalence is relatively high, but the prevalence of

  5. A POPULATION OF ACCRETED SMALL MAGELLANIC CLOUD STARS IN THE LARGE MAGELLANIC CLOUD

    SciTech Connect

    Olsen, Knut A. G.; Blum, Robert D.; Zaritsky, Dennis; Boyer, Martha L.; Gordon, Karl D. E-mail: rblum@noao.edu E-mail: mboyer@stsci.edu

    2011-08-10

    We present an analysis of the stellar kinematics of the Large Magellanic Cloud (LMC) based on {approx}5900 new and existing velocities of massive red supergiants, oxygen-rich and carbon-rich asymptotic giant branch (AGB) stars, and other giants. After correcting the line-of-sight velocities for the LMC's space motion and accounting for asymmetric drift in the AGB population, we derive a rotation curve that is consistent with all of the tracers used, as well as that of published H I data. The amplitude of the rotation curve is v{sub 0} = 87 {+-} 5 km s{sup -1} beyond a radius R{sub 0} = 2.4 {+-} 0.1 kpc and has a position angle of the kinematic line of nodes of {theta} = 142 deg. {+-} 5 deg. By examining the outliers from our fits, we identify a population of 376 stars, or {approx}>5% of our sample, that have line-of-sight velocities that apparently oppose the sense of rotation of the LMC disk. We find that these kinematically distinct stars are either counter-rotating in a plane closely aligned with the LMC disk, or rotating in the same sense as the LMC disk, but in a plane that is inclined by 54 deg. {+-} 2 deg. to the LMC. Their kinematics clearly link them to two known H I arms, which have previously been interpreted as being pulled out from the LMC. We measure metallicities from the Ca triplet lines of {approx}1000 LMC field stars and 30 stars in the kinematically distinct population. For the LMC field, we find a median [Fe/H] = -0.56 {+-} 0.02 with dispersion of 0.5 dex, while for the kinematically distinct stars the median [Fe/H] is -1.25 {+-} 0.13 with a dispersion of 0.7 dex. The metallicity differences provide strong evidence that the kinematically distinct population originated in the Small Magellanic Cloud. This interpretation has the consequence that the H I arms kinematically associated with the stars are likely falling into the LMC, instead of being pulled out.

  6. Large scale, synchronous variability of marine fish populations driven by commercial exploitation

    PubMed Central

    Frank, Kenneth T.; Petrie, Brian; Leggett, William C.; Boyce, Daniel G.

    2016-01-01

    Synchronous variations in the abundance of geographically distinct marine fish populations are known to occur across spatial scales on the order of 1,000 km and greater. The prevailing assumption is that this large-scale coherent variability is a response to coupled atmosphere–ocean dynamics, commonly represented by climate indexes, such as the Atlantic Multidecadal Oscillation and North Atlantic Oscillation. On the other hand, it has been suggested that exploitation might contribute to this coherent variability. This possibility has been generally ignored or dismissed on the grounds that exploitation is unlikely to operate synchronously at such large spatial scales. Our analysis of adult fishing mortality and spawning stock biomass of 22 North Atlantic cod (Gadus morhua) stocks revealed that both the temporal and spatial scales in fishing mortality and spawning stock biomass were equivalent to those of the climate drivers. From these results, we conclude that greater consideration must be given to the potential of exploitation as a driving force behind broad, coherent variability of heavily exploited fish species. PMID:27382163

  7. Enduring, Sexually Dimorphic Impact of In Utero Exposure to Elevated Levels of Glucocorticoids on Midbrain Dopaminergic Populations

    PubMed Central

    Gillies, Glenda E.; Virdee, Kanwar; Pienaar, Ilse; Al-Zaid, Felwah; Dalley, Jeffrey W.

    2016-01-01

    Glucocorticoid hormones (GCs) released from the fetal/maternal glands during late gestation are required for normal development of mammalian organs and tissues. Accordingly, synthetic glucocorticoids have proven to be invaluable in perinatal medicine where they are widely used to accelerate fetal lung maturation when there is risk of pre-term birth and to promote infant survival. However, clinical and pre-clinical studies have demonstrated that inappropriate exposure of the developing brain to elevated levels of GCs, either as a result of clinical over-use or after stress-induced activation of the fetal/maternal adrenal cortex, is linked with significant effects on brain structure, neurological function and behaviour in later life. In order to understand the underlying neural processes, particular interest has focused on the midbrain dopaminergic systems, which are critical regulators of normal adaptive behaviours, cognitive and sensorimotor functions. Specifically, using a rodent model of GC exposure in late gestation (approximating human brain development at late second/early third trimester), we demonstrated enduring effects on the shape and volume of the ventral tegmental area (VTA) and substantia nigra pars compacta (SNc) (origins of the mesocorticolimbic and nigrostriatal dopaminergic pathways) on the topographical organisation and size of the dopaminergic neuronal populations and astrocytes within these nuclei and on target innervation density and neurochemical markers of dopaminergic transmission (receptors, transporters, basal and amphetamine-stimulated dopamine release at striatal and prefrontal cortical sites) that impact on the adult brain. The effects of antenatal GC treatment (AGT) were both profound and sexually-dimorphic, not only in terms of quantitative change but also qualitatively, with several parameters affected in the opposite direction in males and females. Although such substantial neurobiological changes might presage marked behavioural

  8. Gambling behavior and problem gambling reflecting social transition and traumatic childhood events among Greenland Inuit: a cross-sectional study in a large indigenous population undergoing rapid change.

    PubMed

    Larsen, Christina Viskum Lytken; Curtis, Tine; Bjerregaard, Peter

    2013-12-01

    An increase in social pathologies is a key feature in indigenous populations undergoing transition. The Greenland Inuit are a large indigenous population constituting a majority in their own country, which makes it possible to investigate differences within the population. This led us to study gambling behavior and problem gambling among Greenland Inuit in relation to the ongoing social transition and traumatic events during childhood. A large representative cross-sectional study was conducted among Greenland Inuit (n = 2,189). Data was collected among adults (18+) in 9 towns and 13 villages in Greenland from 2005 to 2010. Problem gambling, gambling behavior and traumatic childhood events were measured through a self-administered questionnaire. The lie/bet screen was used to identify past year and lifetime problem gambling. Social transition was measured as place of residence and a combination of residence, education and occupation. The lifetime prevalence of problem gambling was 16 % among men and 10 % among women (p < 0.0001); and higher in towns (19 %) compared to the capital of Nuuk (11 %) and in villages (12 %) (men only, p = 0.020). Lifetime problem gambling was associated with social transition (p = 0.023), alcohol problems in childhood home (p = 0.001/p = 0.002) and sexual abuse in childhood (women only, p = 0.030). A comparably high prevalence of lifetime problem gambling among Greenland Inuit adds problem gambling to the list of social pathologies in Greenland. A significant association between lifetime problem gambling, social transition and traumatic childhood events suggests people caught between tradition and modern ways of life are more vulnerable to gambling problems.

  9. Evidence of pheromonal constancy among sexual and asexual females in a population of fall cankerworm,Alsophila pometaria (Lepidoptera: Geometridae).

    PubMed

    Mitter, C; Klun, J A

    1987-08-01

    The compounds (Z,Z,Z)-3,6,9-nonadecatriene (I), (Z,Z,Z,E)-(II), and (Z,Z,Z,Z)-3,6,9,11-nonadecatetraene (III) have been implicated as components of the female sex pheromone of the fall cankerworm. Chromatographie determination of the proportions of these compounds in individual females of sympatric asexual and sexual reproductive forms of the species, with concurrent analysis of the electrophoretic profiles of the same females, showed that the I: II: III proportion of compounds was constant across electrophoretically differing asexual genotypes and between these and the sexual form. Life-history characters, in contrast, typically show great variation among these genetic groups. The results indicate that pheromonal constancy is maintained in a reproductive system that is theoretically vulnerable to selective pressures that would lead to heterogeneity in the species' pheromonal communication channel.

  10. Effects of a large northern European no-take zone on flatfish populations.

    PubMed

    Florin, A-B; Bergström, U; Ustups, D; Lundström, K; Jonsson, P R

    2013-10-01

    In March 2006, a 360 km² no-take zone (NTZ) was established north of Gotland in the central Baltic Sea, with the purpose to scientifically evaluate the effects of a fishing ban on flatfish populations. A monitoring programme was set up to study the populations in the NTZ and in a reference area east of Gotland where the fishing pressure was high. The programme included fishing with multimesh survey nets, modelling of potential larval export and estimation of fish consumption by large marine predators. Overall, the results showed a clear positive effect of the NTZ on turbot Scophthalmus maximus, with higher densities in the closed area compared with the fished area and also higher densities after closure compared with before. The NTZ also had older individuals and a more even sex ratio. This, in combination with a high potential for larval export from the NTZ to Gotland, shows that the marine reserve may be important for maintaining a viable S. maximus stock at Gotland. Also, for flounder Platichthys flesus, the densities were higher in the NTZ compared to the reference area and there was a net larval export to the fished area. For both species, density-dependent growth was evident, with a lower length at age in the closed area. Potential predation by grey seal Halichoerus grypus and great cormorant Phalacrocorax carbo sinesis on flatfishes, that could hamper the evaluation of the marine reserve, was also addressed. Taken together, the results show that there are clear benefits of the fishing ban for both flatfish species within the NTZ, while the net effects on fisheries are difficult to quantify.

  11. Large population survey: strengths and limits. Methodology of the EDIFICE survey.

    PubMed

    Roussel, Claire; Touboul, Chantal

    2011-01-01

    In France, mass screening for breast and colon cancer issupported by the French National Cancer Institute (INCa). In these nationwide screening campaigns, individuals aged between 50 and 74 years receive a personalized letter inviting them for a screening examination every 2 years. Prostate cancer screening is, however, still controversial and has not been included in the INCa recommendations so far. Research organizations are particularly interested in screening and indeed, several studies have been conducted in France and other countries to examine the different aspects of the subject. To provide actual benefits, screening should be undertaken on a regular scheduled basis. Therefore, several studies have assessed the factors influencing the participation rate of women in breast cancer screening in France (). The Institut National de Prévention et d'Education pour la Santé conducted one of these in 2005: the Baromètre Cancer (including 4046 individuals aged 15 years or older, interviewed by telephone) analysed beliefs and perceptions about cancer screening and studied attendance rates for breast, colon and prostate cancer (including scheduled screening). No previous survey has ever been conducted simultaneously among the general population and physicians with regard to individual and scheduled screening for breast cancer and colorectal cancer (CRC) or individual screening for prostate cancer. EDIFICE is thus the first large-scale survey to assess screening practices in France by analysing the targeted population on the one hand and the clinical practice of French general practitioners (GPs) on the other hand, using the 'mirror study' method to compare results. Two national surveys were conducted in 2005 and 2008. In 2005, only 22 geographical regions were included in the screening programme for CRC.

  12. Validation of Screening Questions for Limited Health Literacy in a Large VA Outpatient Population

    PubMed Central

    Griffin, Joan M.; Partin, Melissa R.; Noorbaloochi, Siamak; Grill, Joseph P.; Snyder, Annamay; Bradley, Katharine A.; Nugent, Sean M.; Baines, Alisha D.; VanRyn, Michelle

    2008-01-01

    Objectives Previous studies have shown that a single question may identify individuals with inadequate health literacy. We evaluated and compared the performance of 3 health literacy screening questions for detecting patients with inadequate or marginal health literacy in a large VA population. Methods We conducted in-person interviews among a random sample of patients from 4 VA medical centers that included 3 health literacy screening questions and 2 validated health literacy measures. Patients were classified as having inadequate, marginal, or adequate health literacy based on the Short Test of Functional Health Literacy in Adults (S-TOFHLA) and the Rapid Estimate of Adult Literacy in Medicine (REALM). We evaluated the ability of each of 3 questions to detect: 1) inadequate and the combination of “inadequate or marginal” health literacy based on the S-TOFHLA and 2) inadequate and the combination of “inadequate or marginal” health literacy based on the REALM. Measurements and Main Results Of 4,384 patients, 1,796 (41%) completed interviews. The prevalences of inadequate health literacy were 6.8% and 4.2%, based on the S-TOHFLA and REALM, respectively. Comparable prevalences for marginal health literacy were 7.4% and 17%, respectively. For detecting inadequate health literacy, “How confident are you filling out medical forms by yourself?” had the largest area under the Receiver Operating Characteristic Curve (AUROC) of 0.74 (95% CI: 0.69–0.79) and 0.84 (95% CI: 0.79–0.89) based on the S-TOFHLA and REALM, respectively. AUROCs were lower for detecting “inadequate or marginal” health literacy than for detecting inadequate health literacy for each of the 3 questions. Conclusion A single question may be useful for detecting patients with inadequate health literacy in a VA population. PMID:18335281

  13. Circulating Osteopontin and Prediction of Hepatocellular Carcinoma Development in a Large European Population.

    PubMed

    Duarte-Salles, Talita; Misra, Sandeep; Stepien, Magdalena; Plymoth, Amelie; Muller, David; Overvad, Kim; Olsen, Anja; Tjønneland, Anne; Baglietto, Laura; Severi, Gianluca; Boutron-Ruault, Marie-Christine; Turzanski-Fortner, Renee; Kaaks, Rudolf; Boeing, Heiner; Aleksandrova, Krasimira; Trichopoulou, Antonia; Lagiou, Pagona; Bamia, Christina; Pala, Valeria; Palli, Domenico; Mattiello, Amalia; Tumino, Rosario; Naccarati, Alessio; Bueno-de-Mesquita, H B As; Peeters, Petra H; Weiderpass, Elisabete; Quirós, J Ramón; Agudo, Antonio; Sánchez-Cantalejo, Emilio; Ardanaz, Eva; Gavrila, Diana; Dorronsoro, Miren; Werner, Mårten; Hemmingsson, Oskar; Ohlsson, Bodil; Sjöberg, Klas; Wareham, Nicholas J; Khaw, Kay-Tee; Bradbury, Kathryn E; Gunter, Marc J; Cross, Amanda J; Riboli, Elio; Jenab, Mazda; Hainaut, Pierre; Beretta, Laura

    2016-09-01

    We previously identified osteopontin (OPN) as a promising marker for the early detection of hepatocellular carcinoma (HCC). In this study, we investigated the association between prediagnostic circulating OPN levels and HCC incidence in a large population-based cohort. A nested case-control study was conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. During a mean follow-up of 4.8 years, 100 HCC cases were identified. Each case was matched to two controls and OPN levels were measured in baseline plasma samples. Viral hepatitis, liver function, and α-fetoprotein (AFP) tests were also conducted. Conditional logistic regression models were used to calculate multivariable odds ratio (OR) and 95% confidence intervals (95% CI) for OPN levels in relation to HCC. Receiver operating characteristics curves were constructed to determine the discriminatory accuracy of OPN alone or in combination with other liver biomarkers in the prediction of HCC. OPN levels were positively associated with HCC risk (per 10% increment, ORmultivariable = 1.30; 95% CI, 1.14-1.48). The association was stronger among cases diagnosed within 2 years of follow-up. Adding liver function tests to OPN improved the discriminatory performance for subjects who developed HCC (AUC = 0.86). For cases diagnosed within 2 years, the combination of OPN and AFP was best able to predict HCC risk (AUC = 0.88). The best predictive model for HCC in this low-risk population is OPN in combination with liver function tests. Within 2 years of diagnosis, the combination of OPN and AFP best predicted HCC development, suggesting that measuring OPN and AFP could identify high-risk groups independently of a liver disease diagnosis. Cancer Prev Res; 9(9); 758-65. ©2016 AACR.

  14. The consistency and stability of abundance-occupancy relationships in large-scale population dynamics.

    PubMed

    Zuckerberg, Benjamin; Porter, William F; Corwin, Kimberley

    2009-01-01

    1. Abundance-occupancy relationships comprise some of the most general and well-explored patterns in macro-ecology. The theory governing these relationships predicts that species will exhibit a positive interspecific and intraspecific relationship between regional occupancy and local abundance. Abundance-occupancy relationships have important implications in using distributional surveys, such as atlases, to understand and document large-scale population dynamics and the consequences of environmental change. A basic need for interpreting such data bases is a better understanding of whether changes in regional occupancy reflect changes in local abundance across species of varying life-history characteristics. 2. Our objective was to test the predictions of the abundance-occupancy rule using two independent data sets, the New York State Breeding Bird Atlas and the North American Breeding Bird Survey. The New York State Breeding Bird Atlas consists of 5332 25-km(2) survey blocks and is one of the first atlases in the USA to be completed for two time periods (1980-85 and 2000-05). The North American Breeding Survey is a large-scale annual survey intended to document the relative abundance and population change of songbirds throughout the USA. 3. We found that regional occupancy was positively correlated with relative abundance across 98 (beta = 0.60 +/- 0.11 SE, P < 0.001, R(2) = 0.60) and 85 species (beta = 0.67 +/- 0.06 SE, P < 0.001, R(2) = 0.57) in two separate time periods. This relationship proved stable over time and was notably consistent between breeding habitat groups and migratory guilds. 4. Between 1980 and 2005, changes in regional occupancy were highly correlated with long-term abundance trend estimates for 75 species (beta = 5.73 +/- 0.24 SE, P < 0.001, R(2) = 0.88). Over a 20-year period, woodland and resident birds showed an increase in occupancy while grassland species showed the greatest decline; these patterns were mirrored by changes in local

  15. Prevalence, Characteristics, and Associations of Sexual Abuse with Sociodemographics and Consensual Sex in a Population-Based Sample of Swedish Adolescents

    ERIC Educational Resources Information Center

    Priebe, Gisela; Svedin, Carl Goran

    2009-01-01

    The purpose of this study was to investigate lifetime prevalence and characteristics of self-reported child sexual abuse and associations between child sexual abuse, gender, sociodemographic data, and consensual sexual experiences. A questionnaire was completed by 4,339 Swedish high school seniors. Three categories of child sexual abuse were…

  16. Genetics of single-cell protein abundance variation in large yeast populations

    NASA Astrophysics Data System (ADS)

    Albert, Frank W.; Treusch, Sebastian; Shockley, Arthur H.; Bloom, Joshua S.; Kruglyak, Leonid

    2014-02-01

    Variation among individuals arises in part from differences in DNA sequences, but the genetic basis for variation in most traits, including common diseases, remains only partly understood. Many DNA variants influence phenotypes by altering the expression level of one or several genes. The effects of such variants can be detected as expression quantitative trait loci (eQTL). Traditional eQTL mapping requires large-scale genotype and gene expression data for each individual in the study sample, which limits sample sizes to hundreds of individuals in both humans and model organisms and reduces statistical power. Consequently, many eQTL are probably missed, especially those with smaller effects. Furthermore, most studies use messenger RNA rather than protein abundance as the measure of gene expression. Studies that have used mass-spectrometry proteomics reported unexpected differences between eQTL and protein QTL (pQTL) for the same genes, but these studies have been even more limited in scope. Here we introduce a powerful method for identifying genetic loci that influence protein expression in the yeast Saccharomyces cerevisiae. We measure single-cell protein abundance through the use of green fluorescent protein tags in very large populations of genetically variable cells, and use pooled sequencing to compare allele frequencies across the genome in thousands of individuals with high versus low protein abundance. We applied this method to 160 genes and detected many more loci per gene than previous studies. We also observed closer correspondence between loci that influence protein abundance and loci that influence mRNA abundance of a given gene. Most loci that we detected were clustered in `hotspots' that influence multiple proteins, and some hotspots were found to influence more than half of the proteins that we examined. The variants that underlie these hotspots have profound effects on the gene regulatory network and provide insights into genetic variation in cell

  17. Effect of candidate gene polymorphisms on reproductive traits in a Large White pig population.

    PubMed

    Sato, Shuji; Kikuchi, Takashi; Uemoto, Yoshinobu; Mikawa, Satoshi; Suzuki, Keiichi

    2016-12-01

    The objective of this study was to test for association of candidate single nucleotide polymorphisms (SNPs) with sow prolificacy reproductive traits, such as litter size, ovulation rate and lifetime performance, in gilts of a Large White pig population. Preliminary research on 25 animals selected from the high- and low-performance groups of 347 animals with case-control studies indicated that seven genes were associated with total number of piglets born (TNB). Six of the seven genes were associated with reproductive traits, including TNB, number of piglets born alive (NBA) and average weight of piglet weaning (AWW). A MBL2 SNP was significantly associated with TNB and NBA in first parity. A CFB SNP was associated with TNB in first parity. An ACE SNP was associated with TNB in first and second parities. An EGF polymorphism was associated with TNB, NBA and AWW in second parity. A KCNC2 polymorphism was significantly associated with TNB and NBA in second parity. A SLC22A5 SNP was associated with TNB and NBA in second parity. Six candidate SNPs were associated with TNB; the only exception was a PRKAG3 polymorphism. A candidate gene approach enables some of these polymorphisms to be used in genetic improvement programs based on marker-assisted selection.

  18. A Deployable In Vivo EPR Tooth Dosimeter for Triage After a Radiation Event Involving Large Populations

    PubMed Central

    Williams, Benjamin B.; Dong, Ruhong; Flood, Ann Barry; Grinberg, Oleg; Kmiec, Maciej; Lesniewski, Piotr N.; Matthews, Thomas P.; Nicolalde, Roberto J.; Raynolds, Tim; Salikhov, Ildar K.; Swartz, Harold M.

    2011-01-01

    In order to meet the potential need for emergency large-scale retrospective radiation biodosimetry following an accident or attack, we have developed instrumentation and methodology for in vivo electron paramagnetic resonance spectroscopy to quantify concentrations of radiation-induced radicals within intact teeth. This technique has several very desirable characteristics for triage, including independence from confounding biologic factors, a non-invasive measurement procedure, the capability to make measurements at any time after the event, suitability for use by non-expert operators at the site of an event, and the ability to provide immediate estimates of individual doses. Throughout development there has been a particular focus on the need for a deployable system, including instrumental requirements for transport and field use, the need for high throughput, and use by minimally trained operators. Numerous measurements have been performed using this system in clinical and other non-laboratory settings, including in vivo measurements with unexposed populations as well as patients undergoing radiation therapies. The collection and analyses of sets of three serially-acquired spectra with independent placements of the resonator, in a data collection process lasting approximately five minutes, provides dose estimates with standard errors of prediction of approximately 1 Gy. As an example, measurements were performed on incisor teeth of subjects who had either received no irradiation or 2 Gy total body irradiation for prior bone marrow transplantation; this exercise provided a direct and challenging test of our capability to identify subjects who would be in need of acute medical care. PMID:21966241

  19. The uterine lumen of the pregnant guinea-pig contains a large macrophage population.

    PubMed

    Sype, W; Lentfer, K; Kimberly, D J; Smith, M K; Van Meter, L; Thornburg, K L

    1989-01-01

    Cellular constituents of the uterine lumen were investigated. Fourteen pregnant sows of 40 + days' gestation were anaesthetized and naturally occurring peritoneal fluid was collected. A uterine horn was delivered and 0.25 ml Gey's solution injected into the uterine lumen to collect free cells. The fluid was aspirated into a syringe and the cells extracted, counted and prepared for phagocytosis experiments and microscopy. The cells were stained with alpha-naphthyl-acetate-esterase (ANAE) to determine the fraction that was non-specific esterase-positive, a feature of mononuclear phagocytes. Differential cells counts were also made. Both uterine and peritoneal compartments yielded large numbers of cells (greater than 10(6)/ml). Peritoneal fluid cells were 47 +/- 6 per cent (SD) macrophages and 49 +/- 6 per cent eosinophils (the remainder being 'other' cells); 47 +/- 6 per cent also stained positively for ANAE. Uterine cells were 78 +/- 12 per cent macrophages, the remainder being mostly lymphocytes (18 +/- 11 per cent); 85 +/- 13 per cent stained positively with ANAE. Electron microscopy of the uterine cells confirmed that most had morphology consistent with being mononuclear phagocytes. Uterine and peritoneal cells phagocytized carbon particles and yeast cells when incubated at 37 degrees C. The origin and role of this macrophage population is unknown but uterine lumenal macrophages may be present to remove antigen-antibody complexes thus facilitating uptake of maternally derived IgG by the fetal yolk sac.

  20. Sleep and academic performance in later adolescence: results from a large population-based study.

    PubMed

    Hysing, Mari; Harvey, Allison G; Linton, Steven J; Askeland, Kristin G; Sivertsen, Børge

    2016-06-01

    The aim of the current study was to assess the association between sleep duration and sleep patterns and academic performance in 16-19 year-old adolescents using registry-based academic grades. A large population-based study from Norway conducted in 2012, the youth@hordaland-survey, surveyed 7798 adolescents aged 16-19 years (53.5% girls). The survey was linked with objective outcome data on school performance. Self-reported sleep measures provided information on sleep duration, sleep efficiency, sleep deficit and bedtime differences between weekday and weekend. School performance [grade point average (GPA)] was obtained from official administrative registries. Most sleep parameters were associated with increased risk for poor school performance. After adjusting for sociodemographic information, short sleep duration and sleep deficit were the sleep measures with the highest odds of poor GPA (lowest quartile). Weekday bedtime was associated significantly with GPA, with adolescents going to bed between 22:00 and 23:00 hours having the best GPA. Also, delayed sleep schedule during weekends was associated with poor academic performance. The associations were somewhat reduced after additional adjustment for non-attendance at school, but remained significant in the fully adjusted models. In conclusion, the demonstrated relationship between sleep problems and poor academic performance suggests that careful assessment of sleep is warranted when adolescents are underperforming at school. Future studies are needed on the association between impaired sleep in adolescence and later functioning in adulthood.

  1. Assessing sexual problems in women at midlife using the short version of the female sexual function index.

    PubMed

    Chedraui, Peter; Pérez-López, Faustino R

    2015-11-01

    Assessment of sexual function is a complex process, especially in women, which requires in any individual case: time, appropriate training and experience. The prevalence of female sexual dysfunction is quite variable depending on the studied population, assessment methods, comorbid conditions and treatments, and age. A large number of screening methods have been developed over the last decades which range from tedious, exhaustive and boring tools to very simple standardized questionnaires. The 19-item female sexual function index (FSFI-19) is among the most used and useful- instrument designed to assess female sexual function in all types of circumstances, sexual orientation and perform the comparison of transcultural factors. A short 6-item- version of the FSFI-19 has been developed to provide a quick general approach to the six original domains (one item per domain). Nevertheless, further studies are needed to demonstrate its validity in different clinical situations as it has been extensively demonstrated with the original tool.

  2. Conserving large populations of lions - the argument for fences has holes.

    PubMed

    Creel, S; Becker, M S; Durant, S M; M'Soka, J; Matandiko, W; Dickman, A J; Christianson, D; Dröge, E; Mweetwa, T; Pettorelli, N; Rosenblatt, E; Schuette, P; Woodroffe, R; Bashir, S; Beudels-Jamar, R C; Blake, S; Borner, M; Breitenmoser, C; Broekhuis, F; Cozzi, G; Davenport, T R B; Deutsch, J; Dollar, L; Dolrenry, S; Douglas-Hamilton, I; Fitzherbert, E; Foley, C; Hazzah, L; Henschel, P; Hilborn, R; Hopcraft, J G C; Ikanda, D; Jacobson, A; Joubert, B; Joubert, D; Kelly, M S; Lichtenfeld, L; Mace, G M; Milanzi, J; Mitchell, N; Msuha, M; Muir, R; Nyahongo, J; Pimm, S; Purchase, G; Schenck, C; Sillero-Zubiri, C; Sinclair, A R E; Songorwa, A N; Stanley-Price, M; Tehou, C A; Trout, C; Wall, J; Wittemyer, G; Zimmermann, A

    2013-11-01

    Packer et al. reported that fenced lion populations attain densities closer to carrying capacity than unfenced populations. However, fenced populations are often maintained above carrying capacity, and most are small. Many more lions are conserved per dollar invested in unfenced ecosystems, which avoid the ecological and economic costs of fencing.

  3. The Effective Population Size of Malaria Mosquitoes: Large Impact of Vector Control

    PubMed Central

    Athrey, Giridhar; Hodges, Theresa K.; Reddy, Michael R.; Overgaard, Hans J.; Matias, Abrahan; Ridl, Frances C.; Kleinschmidt, Immo; Caccone, Adalgisa; Slotman, Michel A.

    2012-01-01

    Malaria vectors in sub-Saharan Africa have proven themselves very difficult adversaries in the global struggle against malaria. Decades of anti-vector interventions have yielded mixed results—with successful reductions in transmission in some areas and limited impacts in others. These varying successes can be ascribed to a lack of universally effective vector control tools, as well as the development of insecticide resistance in mosquito populations. Understanding the impact of vector control on mosquito populations is crucial for planning new interventions and evaluating existing ones. However, estimates of population size changes in response to control efforts are often inaccurate because of limitations and biases in collection methods. Attempts to evaluate the impact of vector control on mosquito effective population size (Ne) have produced inconclusive results thus far. Therefore, we obtained data for 13–15 microsatellite markers for more than 1,500 mosquitoes representing multiple time points for seven populations of three important vector species—Anopheles gambiae, An. melas, and An. moucheti—in Equatorial Guinea. These populations were exposed to indoor residual spraying or long-lasting insecticidal nets in recent years. For comparison, we also analyzed data from two populations that have no history of organized vector control. We used Approximate Bayesian Computation to reconstruct their demographic history, allowing us to evaluate the impact of these interventions on the effective population size. In six of the seven study populations, vector control had a dramatic impact on the effective population size, reducing Ne between 55%–87%, the exception being a single An. melas population. In contrast, the two negative control populations did not experience a reduction in effective population size. This study is the first to conclusively link anti-vector intervention programs in Africa to sharply reduced effective population sizes of malaria vectors

  4. Population Structure and Dispersal Patterns within and between Atlantic and Mediterranean Populations of a Large-Range Pelagic Seabird

    PubMed Central

    Genovart, Meritxell; Thibault, Jean-Claude; Igual, José Manuel; Bauzà-Ribot, Maria del Mar; Rabouam, Corinne; Bretagnolle, Vincent

    2013-01-01

    Dispersal is critically linked to the demographic and evolutionary trajectories of populations, but in most seabird species it may be difficult to estimate. Using molecular tools, we explored population structure and the spatial dispersal pattern of a highly pelagic but philopatric seabird, the Cory's shearwater Calonectris diomedea. Microsatellite fragments were analysed from samples collected across almost the entire breeding range of the species. To help disentangle the taxonomic status of the two subspecies described, the Atlantic form C. d. borealis and the Mediterranean form C. d. diomedea, we analysed genetic divergence between subspecies and quantified both historical and recent migration rates between the Mediterranean and Atlantic basins. We also searched for evidence of isolation by distance (IBD) and addressed spatial patterns of gene flow. We found a low genetic structure in the Mediterranean basin. Conversely, strong genetic differentiation appeared in the Atlantic basin. Even if the species was mostly philopatric (97%), results suggest recent dispersal between basins, especially from the Atlantic to the Mediterranean (aprox. 10% of migrants/generation across the last two generations). Long-term gene flow analyses also suggested an historical exchange between basins (about 70 breeders/generation). Spatial analysis of genetic variation indicates that distance is not the main factor in shaping genetic structure in this species. Given our results we recommend gathering more data before concluded whether these taxa should be treated as two species or subspecies. PMID:23950986

  5. On the Etiology of Sexual Dysfunction

    ERIC Educational Resources Information Center

    Apfelbaum, Bernard

    1977-01-01

    Lack of consideration of the sexually functional population has led to misconceptions about causes of sexual dysfunction functioning. Automatic functioning can mask effects of pathogenic influences on sexuality, making these effects appear random, confounding etiological issues and creating the belief that causes of sexual dysfunction and disorder…

  6. The Impact of Sexual Orientation on Sexuality and Sexual Practices in North American Medical Students

    PubMed Central

    Breyer, Benjamin N.; Smith, James F.; Eisenberg, Michael L.; Ando, Kathryn A.; Rowen, Tami S.; Shindel, Alan W.

    2013-01-01

    Introduction There has been limited investigation of the sexuality and sexual dysfunction in non-heterosexual subjects by the sexual medicine community. Additional research in these populations is needed. Aims To investigate and compare sexuality and sexual function in students of varying sexual orientations. Methods An internet-based survey on sexuality was administered to medical students in North American between the months of February and July of 2008. Main Outcome Measures All subjects provided information on their ethnodemographic characteristics, sexual orientation, and sexual history. Subjects also completed a series of widely-utilized instruments for the assessment of human sexuality (International Index of Erectile Function [IIEF], Female Sexual Function Index [FSFI], Premature Ejaculation Diagnostic Tool [PEDT], Index of Sex Life [ISL]). Results There were 2,276 completed responses to the question on sexual orientation. 13.2% of male respondents and 4.7% of female respondents reported a homosexual orientation; 2.5% of male and 5.7% of female respondents reported a bisexual orientation. Many heterosexual males and females reported same-sex sexual experiences (4% and 10%, respectively). Opposite-sex experiences were very common in the male and female homosexual population (37% and 44%, respectively). The prevalence of premature ejaculation (PEDT > 8) was similar among heterosexual and homosexual men (16% and 17%, P = 0.7, respectively). Erectile dysfunction (IIEF-EF < 26) was more common in homosexual men relative to heterosexual men (24% vs. 12%, P = 0.02). High risk for female sexual dysfunction (FSFI < 26.55) was more common in heterosexual and bisexual women compared with lesbians (51%, 45%, and 29%, respectively, P = 0.005). Conclusion In this survey of highly educated young professionals, numerous similarities and some important differences in sexuality and sexual function were noted based on sexual orientation. It is unclear whether the

  7. Sexual competitiveness and compatibility between mass-reared sterile flies and wild populations of Anastrepha Ludens (Diptera: Tephritidae) from different regions in Mexico

    SciTech Connect

    Orozco-Davila, D.; Hernandez, R.; Meza, S.; Dominguez, J.

    2007-03-15

    The mass-reared colony of Anastrepha ludens (Loew) currently used in Mexico for suppression of the Mexican fruit fly has been in use for over 10 years. Sterile flies are released into a wide range of environmental conditions as part of an integrated area-wide approach to suppress diverse populations of this pest in the Mexican Republic. This paper assesses the performance of the sterile flies interacting with wild populations from the different environments. We investigated the sexual compatibility and competitiveness of the sterile flies when competing with wild populations from 6 representatives Mexican states: Nuevo Leon, Tamaulipas, Sinaloa, Nayarit, Michoacan, and Chiapas. Results show that the males of the wild populations differed in the time to the onset and peak of sexual activity. Nevertheless, the index of sexual isolation (ISI) reflected sexual compatibility between the populations and the mass-reared strain, indicating that the sterile individuals mate satisfactorily with the wild populations from the 6 states. The male relative performance index (MRPI) showed that the sterile male is as effective in copulating as the wild males. The female relative performance index (FRPI) reflected a general tendency for wild females to copulate in greater proportion than the sterile females, except for the strains from Tamaulipas and Chiapas. In general, the lower participation of the sterile females in copulation increases the possibilities of sterile males to mate with wild females. The relative sterility index (RSI) showed that the acceptance by wild females of the sterile males (25-55%) was similar to that of wild males. Females of the Chiapas strain showed the lowest acceptance of sterile males. Finally, the results obtained in the Fried test (which measures induced sterility in eggs) showed a competitiveness coefficient ranging from 0.2 to 0.5. This suggests that sterile males successfully compete and are compatible with flies from different geographic origins

  8. Sexual Assault

    MedlinePlus

    Sexual assault is any sexual activity to which you haven't freely given your consent. This includes completed ... trust, a friend, an acquaintance, or a stranger. Sexual assault can affect your health in many ways. It ...

  9. Sexual Health

    MedlinePlus

    ... Reproductive System Gynecomastia Help! Is This My Body? Male Reproductive System When Will I Start Developing? Why Are My ... Erection When Waking Up? Is My Penis Normal? Male Reproductive System Sexual Attraction and Orientation Sexual Harassment and Sexual ...

  10. Sexual Health

    MedlinePlus

    ... Irregular. What's Going On? Pap Smears Pelvic Exams Polycystic Ovary Syndrome Sexual Attraction and Orientation Sexual Harassment and Sexual ... My Monthly Cycle Go Back to Normal With PCOS Treatment? For Guys Can I Stop Myself From ...

  11. Sexual Problems

    MedlinePlus

    ... for a healthy life Mental health for men Sexual health for men Male infertility Prostate health Sexual problems ... updates. Enter email address Submit Home > Men's Health > Sexual health for men Men's Health This information in Spanish ( ...

  12. Sexual Health

    MedlinePlus

    ... healthy and enjoyable sex life at any age. Sex and aging Can older adults remain sexually active? ... from sexually transmitted infections. Talking to kids about sex Kids and sexuality — those words strike fear into ...

  13. Sexual Reproduction of Human Fungal Pathogens

    PubMed Central

    Heitman, Joseph; Carter, Dee A.; Dyer, Paul S.; Soll, David R.

    2014-01-01

    We review here recent advances in our understanding of sexual reproduction in fungal pathogens that commonly infect humans, including Candida albicans, Cryptococcus neoformans/gattii, and Aspergillus fumigatus. Where appropriate or relevant, we introduce findings on other species associated with human infections. In particular, we focus on rapid advances involving genetic, genomic, and population genetic approaches that have reshaped our view of how fungal pathogens evolve. Rather than being asexual, mitotic, and largely clonal, as was thought to be prevalent as recently as a decade ago, we now appreciate that the vast majority of pathogenic fungi have retained extant sexual, or parasexual, cycles. In some examples, sexual and parasexual unions of pathogenic fungi involve closely related individuals, generating diversity in the population but with more restricted recombination than expected from fertile, sexual, outcrossing and recombining populations. In other cases, species and isolates participate in global outcrossing populations with the capacity for considerable levels of gene flow. These findings illustrate general principles of eukaryotic pathogen emergence with relevance for other fungi, parasitic eukaryotic pathogens, and both unicellular and multicellular eukaryotic organisms. PMID:25085958

  14. Sexual reproduction of human fungal pathogens.

    PubMed

    Heitman, Joseph; Carter, Dee A; Dyer, Paul S; Soll, David R

    2014-08-01

    We review here recent advances in our understanding of sexual reproduction in fungal pathogens that commonly infect humans, including Candida albicans, Cryptococcus neoformans/gattii, and Aspergillus fumigatus. Where appropriate or relevant, we introduce findings on other species associated with human infections. In particular, we focus on rapid advances involving genetic, genomic, and population genetic approaches that have reshaped our view of how fungal pathogens evolve. Rather than being asexual, mitotic, and largely clonal, as was thought to be prevalent as recently as a decade ago, we now appreciate that the vast majority of pathogenic fungi have retained extant sexual, or parasexual, cycles. In some examples, sexual and parasexual unions of pathogenic fungi involve closely related individuals, generating diversity in the population but with more restricted recombination than expected from fertile, sexual, outcrossing and recombining populations. In other cases, species and isolates participate in global outcrossing populations with the capacity for considerable levels of gene flow. These findings illustrate general principles of eukaryotic pathogen emergence with relevance for other fungi, parasitic eukaryotic pathogens, and both unicellular and multicellular eukaryotic organisms.

  15. The feasibility of using mobile phone technology for sexual behaviour research in a population vulnerable to HIV: a prospective survey with female sex workers in South India.

    PubMed

    Bradley, Janet; Ramesh, B M; Rajaram, S; Lobo, Anil; Gurav, Kaveri; Isac, Shajy; Chandra Shekhar Gowda, G; Pushpalatha, R; Moses, Stephen; Sunil, Kumar D R; Alary, Michel

    2012-01-01

    Sexual behaviour studies are often challenged by sampling, participation and measurement biases, and may be unacceptable to participants. We invited 293 randomly selected female sex workers (FSWs) in Bangalore, India, to participate in a telephone survey, with condom breakage as the main outcome. Free cell phones were supplied and trained interviewers telephoned FSWs daily to ask about all sex acts the previous day. Later, we undertook focus groups to discuss the methodology with the participants. We evaluated technical and operational feasibility; data reliability and measurement error; emotional and fatigue effects; interviewer bias; survey reactivity effects; and user acceptability. Response rates were high, with 84% of invited participants complying fully with the protocol. The study ran smoothly, with little evidence of biases. The methodology was highly acceptable; the respondents enjoyed using a new telephone and being interviewed at times convenient to them. Other reasons for the success of the method were that the study was sanctioned and supported by the sex worker collective, and the interviewers were well trained and developed a strong rapport with the participants. The success of this methodology, and the wealth of data produced, indicates that it can be an important tool for conducting sexual behaviour research in low literacy, high sex volume populations.

  16. The population of X-ray supernova remnants in the Large Magellanic Cloud

    NASA Astrophysics Data System (ADS)

    Maggi, P.; Haberl, F.; Kavanagh, P. J.; Sasaki, M.; Bozzetto, L. M.; Filipović, M. D.; Vasilopoulos, G.; Pietsch, W.; Points, S. D.; Chu, Y.-H.; Dickel, J.; Ehle, M.; Williams, R.; Greiner, J.

    2016-01-01

    Aims: We present a comprehensive X-ray study of the population of supernova remnants (SNRs) in the Large Magellanic Cloud (LMC). Using primarily XMM-Newton observations, we conduct a systematic spectral analysis of LMC SNRs to gain new insight into their evolution and the interplay with their host galaxy. Methods: We combined all the archival XMM-Newton observations of the LMC with those of our Very Large Programme LMC survey. We produced X-ray images and spectra of 51 SNRs, out of a list of 59 objects compiled from the literature and augmented with newly found objects. Using a careful modelling of the background, we consistently analysed all the X-ray spectra and measure temperatures, luminosities, and chemical compositions. The locations of SNRs are compared to the distributions of stars, cold gas, and warm gas in the LMC, and we investigated the connection between the SNRs and their local environment, characterised by various star formation histories. We tentatively typed all LMC SNRs, in order to constrain the ratio of core-collapse to type Ia SN rates in the LMC. We also compared the column densities derived from X-ray spectra to H i maps, thus probing the three-dimensional structure of the LMC. Results: This work provides the first homogeneous catalogue of the X-ray spectral properties of SNRs in the LMC. It offers a complete census of LMC remnants whose X-ray emission exhibits Fe K lines (13% of the sample), or reveals the contribution from hot supernova ejecta (39%), which both give clues to the progenitor types. The abundances of O, Ne, Mg, Si, and Fe in the hot phase of the LMC interstellar medium are found to be between 0.2 and 0.5 times the solar values with a lower abundance ratio [α/Fe] than in the Milky Way. The current ratio of core-collapse to type Ia SN rates in the LMC is constrained to NCC/NIa=1.35(-0.24+0.11), which is lower than in local SN surveys and galaxy clusters. Our comparison of the X-ray luminosity functions of SNRs in Local Group

  17. Refractory Hypertension: Determination of Prevalence, Risk Factors and Comorbidities in a Large, Population-Based Cohort

    PubMed Central

    Calhoun, David A.; Booth, John N.; Oparil, Suzanne; Irvin, Marguerite R.; Shimbo, Daichi; Lackland, Daniel T.; Howard, George; Safford, Monika M.; Muntner, Paul

    2014-01-01

    Refractory hypertension is an extreme phenotype of antihypertensive treatment failure. Participants in the REasons for Geographic And Racial Differences in Stroke (REGARDS) Study, a large (n=30,239), population-based cohort were evaluated to determine the prevalence of refractory hypertension and associated cardiovascular risk factors and comorbidities. Refractory hypertension was defined as uncontrolled blood pressure (systolic/diastolic ≥ 140/90 mm Hg) on ≥ 5 antihypertensive drug classes. Participants with resistant hypertension (systolic/diastolic ≥140/90 mm Hg on ≥ 3 or<140/90 mm Hg on ≥ 4 antihypertensive classes) and all treated hypertensive participants served as comparator groups. Of 14,809 REGARDS participants receiving antihypertensive treatment, 78 (0.5%) had refractory hypertension. The prevalence of refractory hypertension was 3.6% among participants with resistant hypertension(n=2,144) and 41.7% among participants on 5 or more antihypertensive drug classes. Among all hypertensive participants, African American race, male gender, living in the stroke belt or buckle, higher body mass index, lower heart rate, reduced estimated glomerular filtration rate, albuminuria, diabetes and history of stroke and coronary heart disease were associated with refractory hypertension. Compared to resistant hypertension, prevalence ratios for refractory hypertension were increased for African Americans (3.00, 95% CI 1.68 – 5.37) and those with albuminuria (2.22, 95% CI 1.40 – 3.52) and diabetes (2.09, 95% CI 1.32 – 3.31). The median 10-year Framingham risk for coronary heart disease and stroke was higher among participants with refractory hypertension compared to either comparator group. These data indicate that while resistant hypertension is relatively common among treated hypertensive patients, true antihypertensive treatment failure is rare. PMID:24324035

  18. Novel Anthropometry Based on 3D-Bodyscans Applied to a Large Population Based Cohort

    PubMed Central

    Löffler-Wirth, Henry; Willscher, Edith; Ahnert, Peter; Wirkner, Kerstin; Engel, Christoph; Loeffler, Markus; Binder, Hans

    2016-01-01

    Three-dimensional (3D) whole body scanners are increasingly used as precise measuring tools for the rapid quantification of anthropometric measures in epidemiological studies. We analyzed 3D whole body scanning data of nearly 10,000 participants of a cohort collected from the adult population of Leipzig, one of the largest cities in Eastern Germany. We present a novel approach for the systematic analysis of this data which aims at identifying distinguishable clusters of body shapes called body types. In the first step, our method aggregates body measures provided by the scanner into meta-measures, each representing one relevant dimension of the body shape. In a next step, we stratified the cohort into body types and assessed their stability and dependence on the size of the underlying cohort. Using self-organizing maps (SOM) we identified thirteen robust meta-measures and fifteen body types comprising between 1 and 18 percent of the total cohort size. Thirteen of them are virtually gender specific (six for women and seven for men) and thus reflect most abundant body shapes of women and men. Two body types include both women and men, and describe androgynous body shapes that lack typical gender specific features. The body types disentangle a large variability of body shapes enabling distinctions which go beyond the traditional indices such as body mass index, the waist-to-height ratio, the waist-to-hip ratio and the mortality-hazard ABSI-index. In a next step, we will link the identified body types with disease predispositions to study how size and shape of the human body impact health and disease. PMID:27467550

  19. Population census of a large common tern colony with a small unmanned aircraft.

    PubMed

    Chabot, Dominique; Craik, Shawn R; Bird, David M

    2015-01-01

    Small unmanned aircraft systems (UAS) may be useful for conducting high-precision, low-disturbance waterbird surveys, but limited data exist on their effectiveness. We evaluated the capacity of a small UAS to census a large (>6,000 nests) coastal Common tern (Sterna hirundo) colony of which ground surveys are particularly disruptive and time-consuming. We compared aerial photographic tern counts to ground nest counts in 45 plots (5-m radius) throughout the colony at three intervals over a nine-day period in order to identify sources of variation and establish a coefficient to estimate nest numbers from UAS surveys. We also compared a full colony ground count to full counts from two UAS surveys conducted the following day. Finally, we compared colony disturbance levels over the course of UAS flights to matched control periods. Linear regressions between aerial and ground counts in plots had very strong correlations in all three comparison periods (R2 = 0.972-0.989, P < 0.001) and regression coefficients ranged from 0.928-0.977 terns/nest. Full colony aerial counts were 93.6% and 94.0%, respectively, of the ground count. Varying visibility of terns with ground cover, weather conditions and image quality, and changing nest attendance rates throughout incubation were likely sources of variation in aerial detection rates. Optimally timed UAS surveys of Common tern colonies following our method should yield population estimates in the 93-96% range of ground counts. Although the terns were initially disturbed by the UAS flying overhead, they rapidly habituated to it. Overall, we found no evidence of sustained disturbance to the colony by the UAS. We encourage colonial waterbird researchers and managers to consider taking advantage of this burgeoning technology.

  20. Refractory hypertension: determination of prevalence, risk factors, and comorbidities in a large, population-based cohort.

    PubMed

    Calhoun, David A; Booth, John N; Oparil, Suzanne; Irvin, Marguerite R; Shimbo, Daichi; Lackland, Daniel T; Howard, George; Safford, Monika M; Muntner, Paul

    2014-03-01

    Refractory hypertension is an extreme phenotype of antihypertensive treatment failure. Participants in the REasons for Geographic And Racial Differences in Stroke (REGARDS) Study, a large (n=30 239), population-based cohort were evaluated to determine the prevalence of refractory hypertension and associated cardiovascular risk factors and comorbidities. Refractory hypertension was defined as uncontrolled blood pressure (systolic/diastolic, ≥140/90 mm Hg) on ≥5 antihypertensive drug classes. Participants with resistant hypertension (systolic/diastolic, ≥140/90 mm Hg on ≥3 or <140/90 mm Hg on ≥4 antihypertensive classes) and all participants treated for hypertension served as comparator groups. Of 14 809 REGARDS participants receiving antihypertensive treatment, 78 (0.5%) had refractory hypertension. The prevalence of refractory hypertension was 3.6% among participants with resistant hypertension (n=2144) and 41.7% among participants on ≥5 antihypertensive drug classes. Among all participants with hypertension, black race, male sex, living in the stroke belt or buckle, higher body mass index, lower heart rate, reduced estimated glomerular filtration rate, albuminuria, diabetes mellitus, and history of stroke and coronary heart disease were associated with refractory hypertension. Compared with resistant hypertension, prevalence ratios for refractory hypertension were increased for blacks (3.00; 95% confidence interval, 1.68-5.37) and those with albuminuria (2.22; 95% confidence interval, 1.40-3.52) and diabetes mellitus (2.09; 95% confidence interval, 1.32-3.31). The median 10-year Framingham risk for coronary heart disease and stroke was higher among participants with refractory hypertension when compared with those with either comparator group. These data indicate that although resistant hypertension is relatively common among treated patients with hypertension, true antihypertensive treatment failure is rare.

  1. Coffee and green tea as a large source of antioxidant polyphenols in the Japanese population.

    PubMed

    Fukushima, Yoichi; Ohie, Takashi; Yonekawa, Yasuhiko; Yonemoto, Kohei; Aizawa, Hiroki; Mori, Yoko; Watanabe, Makoto; Takeuchi, Masato; Hasegawa, Maiko; Taguchi, Chie; Kondo, Kazuo

    2009-02-25

    Food and beverages rich in polyphenols with antioxidant activity are highlighted as a potential factor for risk reduction of lifestyle related diseases. This study was conducted to elucidate total polyphenol consumption from beverages in Japanese people. Total polyphenol (TP) contents in beverages were measured using a modified Folin-Ciocalteu method removing the interference of reduced sugars by using reverse-phase column chromatography. A beverage consumption survey was conducted in the Tokyo and Osaka areas in 2004. Randomly selected male and female subjects (10-59 years old, n = 8768) recorded the amounts and types of all nonalcoholic beverages consumed in a week. Concentration of TP in coffee, green tea, black tea, Oolong tea, barley tea, fruit juice, tomato/vegetable juice, and cocoa drinks were at 200, 115, 96, 39, 9, 34, 69, and 62 mg/100 mL, respectively. Total consumption of beverages in a Japanese population was 1.11 +/- 0.51 L/day, and TP contents from beverages was 853 +/- 512 mg/day. Coffee and green tea shared 50% and 34% of TP consumption in beverages, respectively, and contribution of each of the other beverages was less than 10%. TP contents in 20 major vegetables and 5 fruits were 0-49 mg and 2-55 mg/100 g, respectively. Antioxidant activities, Cu reducing power, and scavenging activities for DPPH and superoxide, of those samples correlated to the TP contents (p < 0.001). Beverages, especially coffee, contributed to a large share of the consumption of polyphenols, as antioxidants, in the Japanese diet.

  2. Modeling population exposure to community noise and air pollution in a large metropolitan area.

    PubMed

    Gan, Wen Qi; McLean, Kathleen; Brauer, Michael; Chiarello, Sarah A; Davies, Hugh W

    2012-07-01

    Epidemiologic studies have shown that both air pollution and community noise are associated with cardiovascular disease mortality. Because road traffic is a major contributor to these environmental pollutants in metropolitan areas, it is plausible that the observed associations may be confounded by coexistent pollutants. As part of a large population-based cohort study to address this concern, we used a noise prediction model to assess annual average community noise levels from transportation sources in metropolitan Vancouver, Canada. The modeled annual average noise level was 64 (inter quartile range 60-68) dB(A) for the region. This model was evaluated by comparing modeled annual daytime A-weighted equivalent continuous noise levels (L(day)) with measured 5-min daytime A-weighted equivalent continuous noise levels (L(eq,day,5 min)) at 103 selected roadside sites in the study region. On average, L(day) was 6.2 (95% CI, 6.0-7.9) dB(A) higher than, but highly correlated (r=0.62; 95% CI, 0.48-0.72) with, L(eq,day,5 min). These results suggest that our model-based noise exposure assessment could approximately reflect actual noise exposure in the study region. Overall, modeled noise levels were not strongly correlated with land use regression estimates of traffic-related air pollutants including black carbon, particulate matter with aerodynamic diameter ≤2.5 μm (PM(2.5)), NO(2) and NO; the highest correlation was with black carbon (r=0.48), whereas the lowest correlation was with PM(2.5) (r=0.18). There was no consistent effect of traffic proximity on the correlations between community noise levels and traffic-related air pollutant concentrations. These results, consistent with previous studies, suggest that it is possible to assess potential adverse cardiovascular effects from long-term exposures to community noise and traffic-related air pollution in prospective epidemiologic studies.

  3. Population Census of a Large Common Tern Colony with a Small Unmanned Aircraft

    PubMed Central

    Chabot, Dominique; Craik, Shawn R.; Bird, David M.

    2015-01-01

    Small unmanned aircraft systems (UAS) may be useful for conducting high-precision, low-disturbance waterbird surveys, but limited data exist on their effectiveness. We evaluated the capacity of a small UAS to census a large (>6,000 nests) coastal Common tern (Sterna hirundo) colony of which ground surveys are particularly disruptive and time-consuming. We compared aerial photographic tern counts to ground nest counts in 45 plots (5-m radius) throughout the colony at three intervals over a nine-day period in order to identify sources of variation and establish a coefficient to estimate nest numbers from UAS surveys. We also compared a full colony ground count to full counts from two UAS surveys conducted the following day. Finally, we compared colony disturbance levels over the course of UAS flights to matched control periods. Linear regressions between aerial and ground counts in plots had very strong correlations in all three comparison periods (R2 = 0.972–0.989, P < 0.001) and regression coefficients ranged from 0.928–0.977 terns/nest. Full colony aerial counts were 93.6% and 94.0%, respectively, of the ground count. Varying visibility of terns with ground cover, weather conditions and image quality, and changing nest attendance rates throughout incubation were likely sources of variation in aerial detection rates. Optimally timed UAS surveys of Common tern colonies following our method should yield population estimates in the 93–96% range of ground counts. Although the terns were initially disturbed by the UAS flying overhead, they rapidly habituated to it. Overall, we found no evidence of sustained disturbance to the colony by the UAS. We encourage colonial waterbird researchers and managers to consider taking advantage of this burgeoning technology. PMID:25874997

  4. Understanding sexual harassment using aggregate construct models.

    PubMed

    Nye, Christopher D; Brummel, Bradley J; Drasgow, Fritz

    2014-11-01

    Sexual harassment has received a substantial amount of empirical attention over the past few decades, and this research has consistently shown that experiencing these behaviors has a detrimental effect on employees' well-being, job attitudes, and behaviors at work. However, these findings, and the conclusions that are drawn from them, make the implicit assumption that the empirical models used to examine sexual harassment are properly specified. This article presents evidence that properly specified aggregate construct models are more consistent with theoretical structures and definitions of sexual harassment and can result in different conclusions about the nomological network of harassment. Results from 3 large samples, 2 military and 1 from a civilian population, are used to illustrate the differences between aggregate construct and reflective indicator models of sexual harassment. These analyses suggested that the factor structure and the nomological network of sexual harassment differ when modeling harassment as an aggregate construct. The implications of these results for the continued study of sexual harassment are discussed. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  5. Assessing population effects from entrainment of fish at a large volume water intake

    SciTech Connect

    Gray, R.H.; Page, T.L.; Neitzel, D.A.; Dauble, D.D.

    1986-01-01

    A method is described for estimating population effects from entrainment of juvenile chinook salmon (Oncorhynchus tshawytscha) at a steam electric generating station on the Columbia River that required cooperation between power plant operators and fishery biologists. The method involved sampling fish in the river and entrained fish (both marked recaptures and naturally occurring downstream migrants) within the intake, and estimating the 1) total number of fish entrained, 2) size of the natural population, and 3) percent of the natural population affected.

  6. Parents' supportive reactions to sexual orientation disclosure associated with better health: results from a population-based survey of LGB adults in Massachusetts.

    PubMed

    Rothman, Emily F; Sullivan, Mairead; Keyes, Susan; Boehmer, Ulrike

    2012-01-01

    This study investigated associations between coming out to parents, experiences of parental support, and self-reported health behaviors and conditions among a population-based sample of LGB individuals using data collected via the 2002 Massachusetts Behavioral Risk Factor Surveillance System (BRFSS; N = 177). We explored the following two hypotheses: 1) Lesbian, gay, and bisexual (LGB) individuals who had never disclosed their sexual orientation to a parent would report higher levels of risk behaviors and poorer health conditions than those who had come out; and 2) among LGB respondents who had come out to their parents, the individuals whose parents had reacted unsupportively would report higher levels of risk behaviors and poorer health conditions than those who had come out to parents who were supportive. Approximately two thirds of gay and bisexual (GB) males and lesbian and bisexual (LB) females reported receiving adequate social and emotional support from the parent to whom they first disclosed their sexual orientation. Among LB females, no disclosure of sexual orientation to a parent was associated with significantly elevated levels of past-month illicit drug use (AOR 12.16, 95% CI 2.87-51.54), fair or poor self-reported health status (AOR 5.71, 95% CI 1.45-22.51), and >15 days of depression in the past month (AOR 5.95, 95% CI 1.78-19.90), controlling for potential confounders. However, nondisclosure to a parent by GB males was not associated with greater odds of any of the health indicators assessed. Among GB males, those with unsupportive parents were significantly more likely to report current binge drinking (AOR 6.94, 95% CI 1.70-28.35) and >15 days depression in the past month (AOR 6.08, 95% CI 1.15-32.15), and among LB females, those with unsupportive parents were significantly more likely to report lifetime illicit drug use (AOR 11.43, 95% CI 2.50-52.30), and >15 days depression in the past month (AOR 5.51, 95% CI 1.36-22.36). We conclude that coming

  7. Sexual Health

    MedlinePlus

    ... health include Fear of unplanned pregnancy Concerns about infertility Sexually transmitted diseases Chronic diseases such as cancer or heart disease Medicines that affect sexual desire or performance

  8. POPULATION III STAR FORMATION IN LARGE COSMOLOGICAL VOLUMES. I. HALO TEMPORAL AND PHYSICAL ENVIRONMENT

    SciTech Connect

    Crosby, Brian D.; O'Shea, Brian W.; Smith, Britton D.; Turk, Matthew J.; Hahn, Oliver

    2013-08-20

    We present a semi-analytic, computationally inexpensive model to identify halos capable of forming a Population III star in cosmological simulations across a wide range of times and environments. This allows for a much more complete and representative set of Population III star forming halos to be constructed, which will lead to Population III star formation simulations that more accurately reflect the diversity of Population III stars, both in time and halo mass. This model shows that Population III and chemically enriched stars coexist beyond the formation of the first generation of stars in a cosmological simulation until at least z {approx} 10, and likely beyond, though Population III stars form at rates that are 4-6 orders of magnitude lower than chemically enriched stars by z = 10. A catalog of more than 40,000 candidate Population III forming halos were identified, with formation times temporally ranging from z = 30 to z = 10, and ranging in mass from 2.3 Multiplication-Sign 10{sup 5} M{sub Sun} to 1.2 Multiplication-Sign 10{sup 10} M{sub Sun }. At early times, the environment that Population III stars form in is very similar to that of halos hosting chemically enriched star formation. At later times Population III stars are found to form in low-density regions that are not yet chemically polluted due to a lack of previous star formation in the area. Population III star forming halos become increasingly spatially isolated from one another at later times, and are generally closer to halos hosting chemically enriched star formation than to another halo hosting Population III star formation by z {approx} 10.

  9. Comparison of three replication strategies in complex multicellular organisms: Asexual replication, sexual replication with identical gametes, and sexual replication with distinct sperm and egg gametes

    NASA Astrophysics Data System (ADS)

    Tannenbaum, Emmanuel

    2008-01-01

    This paper studies the mutation-selection balance in three simplified replication models. The first model considers a population of organisms replicating via the production of asexual spores. The second model considers a sexually replicating population that produces identical gametes. The third model considers a sexually replicating population that produces distinct sperm and egg gametes. All models assume diploid organisms whose genomes consist of two chromosomes, each of which is taken to be functional if equal to some master sequence, and defective otherwise. In the asexual population, the asexual diploid spores develop directly into adult organisms. In the sexual populations, the haploid gametes enter a haploid pool, where they may fuse with other haploids. The resulting immature diploid organisms then proceed to develop into mature organisms. Based on an analysis of all three models, we find that, as organism size increases, a sexually replicating population can only outcompete an asexually replicating population if the adult organisms produce distinct sperm and egg gametes. A sexual replication strategy that is based on the production of large numbers of sperm cells to fertilize a small number of eggs is found to be necessary in order to maintain a sufficiently low cost for sex for the strategy to be selected for over a purely asexual strategy. We discuss the usefulness of this model in understanding the evolution and maintenance of sexual replication as the preferred replication strategy in complex, multicellular organisms.

  10. Assessing base rates of sexual behavior using the unmatched count technique.

    PubMed

    Starosta, Amy J; Earleywine, Mitch

    2014-01-01

    Estimating the prevalence of sexual behaviors is difficult because of self-report biases. This is particularly relevant in assessing high-risk sexual behaviors for the purpose of reducing the transmission and acquisition of sexually transmitted infections (STIs) and HIV/AIDS. The present study employed the unmatched count technique (UCT), which provides estimates of the prevalence of risky sexual behaviors without requiring participants to confess to socially undesirable or stigmatized behaviors. Compared to a standard, anonymous self-report questionnaire, the UCT protocol revealed that people were less likely to notify their partners about STIs or discuss their history of sexual experiences. Effects were particularly large in women suggesting that women may be more likely to misrepresent their sexual behaviors. The findings suggest that conventional, anonymous self-report questionnaire data of base rates of risky sexual behavior and sexual communication are consistently inaccurate. These discrepant base rates suggest that the UCT might provide a better estimate of the frequency of these behaviors. Results suggest that inconsistent sexual behavior is more rampant than anonymous questionnaires suggest. They also underscore the need for improvements in the anonymity of assessment of sexual behaviors, which could in turn improve the targeting of prevention efforts. Results have important public health implications because accurate assessment of sexual behaviors is crucial for developing effective STI prevention interventions among target populations.

  11. Sexual Functioning in Men Living with a Spinal Cord Injury–A Narrative Literature Review

    PubMed Central

    Sunilkumar, MM; Boston, Patricia; Rajagopal, MR

    2015-01-01

    Background: Sexual dysfunction is a major concern for Indian men living with a spinal cord injury Objectives: To examine the literature related to sexuality traumatic cord injury and its impact on sexual functioning. Materials and Methods: Databases using Cumulative Index to Nursing and Allied Health Literature (CINAHL) 2000–2012, Medline 1989–2012, Applied Social Sciences Index and Abstracts (ASSIA) 1989–2012 and Google Scholar were the search engines used used for literature review. Results: The search yielded a total of 457 articles and only 75 of them were found relevant. The minimum number of articles required to meet the inclusion criteria for this review was 25–30 articles. Out of the 75 articles, 33 were considered relevant or related to the topic of sexual functioning, spinal cord injury, and paraplegia. Six areas were identified: Sexual stigmatization, physiological barriers to sexual satisfaction, clinical aspects of sexual functioning, biomedical approaches to sexual dysfunction, partner satisfaction, and lack of accessibility to sexual education. Conclusion: Spinal cord injury and sexual functioning affects a large segment of the male Indian population, yet most current research focuses on quantitative measurement with the emphasis on ejaculatory dysfunction, orgasm impairment, incontinence, and other physiological dysfunction. Further research is needed to address the subjective accounts of patients themselves with respect to the emotional and social impact of sexual disability. This would help to identify the best possible outcomes for both treatment and rehabilitation. PMID:26600694

  12. Large population sizes mitigate negative effects of variable weather conditions on fruit set in two spring woodland orchids

    PubMed Central

    Jacquemyn, Hans; Brys, Rein; Honnay, Olivier

    2009-01-01

    Global circulation models predict increased climatic variability, which could increase variability in demographic rates and affect long-term population viability. In animal-pollinated species, pollination services, and thus fruit and seed set, may be highly variable among years and sites, and depend on both local environmental conditions and climatic variables. Orchid species may be particularly vulnerable to disruption of their pollination services, as most species depend on pollinators for successful fruit set and because seed germination and seedling recruitment are to some extent dependent on the amount of fruits and seeds produced. Better insights into the factors determining fruit and seed set are therefore indispensable for a better understanding of population dynamics and viability of orchid populations under changing climatic conditions. However, very few studies have investigated spatio-temporal variation in fruit set in orchids. Here, we quantified fruit production in eight populations of the orchid Orchis purpurea that does not reward pollinators and 13 populations of the rewarding Neottia (Listera) ovata during five consecutive years (2002–2006). Fruit production in large populations showed much higher stability than that in small populations and was less affected by extreme weather conditions. Our results highlight the potential vulnerability of small orchid populations to an increasingly variable climate through highly unpredictable fruit-set patterns. PMID:19457885

  13. Delayed sleep phase syndrome in adolescents: prevalence and correlates in a large population based study

    PubMed Central

    2013-01-01

    Background The aims of this study were to estimate the prevalence of Delayed Sleep Phase Syndrome (DSPS) in adolescence, and to examine the association to insomnia and school non-attendance. Methods Data stem from a large population based study in Hordaland County in Norway conducted in 2012, the ung@hordaland study. In all, 10,220 adolescents aged 16–18 years (54% girls) provided self-reported data on a range of sleep parameters: DSPS was defined according to the International Classification of Sleep Disorders, Revised (ICSD-R) criteria, while insomnia was defined according to the Quantitative Criteria for Insomnia. Other sleep parameters included time in bed, sleep duration, sleep efficiency, oversleeping, sleep onset latency, wake after sleep onset, subjective sleep need, sleep deficiency, sleepiness and tiredness. Sleep data were calculated separately for weekdays and weekends. Data on school non-attendance were provided by official registers. Results The prevalence of DSPS was 3.3%, and significantly higher among girls (3.7%) than boys (2.7%). There was a strong overlap between DSPS and insomnia, with more than half of the adolescents with DSPS also meeting the criteria for insomnia (53.8% for boys and 57.1% for girls). Adolescents with DSPS had significantly higher odds ratios (OR) of non-attendance at school. After adjusting for sociodeographical factors, insomnia and depression, the adjusted ORs for days of non-attendance were OR = 3.22 (95% CI: 1.94-5.34) for boys and OR = 1.87 (95% CI: 1.25-2.80) for girls. A similar effect was found for hours of non-attendance for boys, with an adjusted OR = 3.05 (95% CI: 1.89-4.92). The effect for girls was no longer significant after full adjustment (OR =1.48 [95% CI: 0.94-2.32]). Conclusions This is one of the first studies to estimate the prevalence of DSPS in adolescents. The high prevalence of DSPS, and overlap with insomnia, in combination with the odds of school non-attendance, suggest that a broad

  14. Psychosocial pathways to sexual dysfunction among female inmates.

    PubMed

    Baltieri, Danilo Antonio

    2014-08-01

    Although health surveys on sexual issues during incarceration have shown that women report having engaged in sexual activities while in prison, studies on sexual functioning in female inmates have been largely dismissed. This study aimed to assess sexual functioning among incarcerated women and determine the psychometric and sociodemographic features that are possibly related to the risk of sexual dysfunction. This was a cross-sectional study conducted inside a penitentiary for women in São Paulo, Brazil. From June 2006 to June 2010, 315 inmates convicted of robbery or homicide were recruited. High risk of female sexual dysfunction (HRFSD) was measured using the Female Sexual Function Index and participants were also evaluated for alcohol and drug misuse, impulsiveness, depressive symptoms, and psychosocial features. Descriptive statistics and multivariate logistic regression were utilized to analyze the data. Among the participants, 253 (80.32 %) met the criteria for HRFSD. Older age, total time of imprisonment, and depressive symptoms were related to a higher risk, while the status of being married, being Black, having sexual relations with other inmates, and receiving conjugal visits were associated with a lower risk. As only 110 (34.92 %) inmates admitted to having sexual relationships inside prison, we evaluated this sub-sample separately. For this sub-sample, 61 (55.45 %) women met the criteria for HRFSD and the main factors associated with this risk were total time of imprisonment and depressive symptoms. Incarcerated women are uniquely vulnerable because they often have histories of deprivation and violence stemming from multiple sources and experience considerable psychological symptoms as a consequence of imprisonment. With the affected population rarely receiving psychosocial management for sexual dysfunction, service delivery efforts should be intensified to target this high-risk population.

  15. Men with Sexual Problems and Their Partners: Findings from the International Survey of Relationships.

    PubMed

    Rosen, Raymond C; Heiman, Julia R; Long, J Scott; Fisher, William A; Sand, Michael S

    2016-01-01

    Epidemiologic studies of sexual function problems in men have focused on the individual male and related sociodemographic characteristics, individual risk factors and lifestyle concomitants, or medical comorbidities. Insufficient attention has been given to the role of sexual and relationship satisfaction and, more particularly, to the perspective of the couple as causes or correlates of sexual problems in men or women. Previously, we reported results of the first large, multi-national study of sexual satisfaction and relationship happiness in 1,009 midlife and older couples in five countries (Brazil, Germany, Japan, Spain, U.S.). For the present study, we examined, within each problem, the association of four major sexual problems in men (loss of sexual desire, erectile problems, premature ejaculation, delayed/absent orgasm) and multiple problems, with male and female partners' assessments of physical intimacy, sexual satisfaction, and relationship happiness, as well as associations with well-known health and psychosocial correlates of sexual problems in men. Sexual problem rates of men in our survey were generally similar to rates observed in past surveys in the general population, and similar risk factors (age, relationship duration, overall health) were associated with lack of desire, anorgasmia, or erection difficulties in our sample. As in previous surveys, there were few correlates of premature ejaculation. As predicted, men with one or more sexual problems reported decreased relationship happiness as well as decreased sexual satisfaction compared to men without sexual problems. Moreover, female partners of men with sexual problems had reduced relationship happiness and sexual satisfaction, although these latter outcomes were less affected in the women than the men. The association of men's sexual problems with men's and women's satisfaction and relationship happiness were modest, as these couples in long-term, committed relationships were notable for their

  16. Sex differences, sexual selection, and ageing: an experimental evolution approach.

    PubMed

    Maklakov, Alexei A; Bonduriansky, Russell; Brooks, Robert C

    2009-10-01

    Life-history (LH) theory predicts that selection will optimize the trade-off between reproduction and somatic maintenance. Reproductive ageing and finite life span are direct consequences of such optimization. Sexual selection and conflict profoundly affect the reproductive strategies of the sexes and thus can play an important role in the evolution of life span and ageing. In theory, sexual selection can favor the evolution of either faster or slower ageing, but the evidence is equivocal. We used a novel selection experiment to investigate the potential of sexual selection to influence the adaptive evolution of age-specific LH traits. We selected replicate populations of the seed beetle Callosobruchus maculatus for age at reproduction ("Young" and "Old") either with or without sexual selection. We found that LH selection resulted in the evolution of age-specific reproduction and mortality but these changes were largely unaffected by sexual selection. Sexual selection depressed net reproductive performance and failed to promote adaptation. Nonetheless, the evolution of several traits differed between males and females. These data challenge the importance of current sexual selection in promoting rapid adaptation to environmental change but support the hypothesis that sex differences in LH-a historical signature of sexual selection-are key in shaping trait responses to novel selection.

  17. Identification of genetic variants associated with maize flowering time using an extremely large multi-genetic background population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flowering time is one of the major adaptive traits in domestication of maize and an important selection criterion in breeding. To detect more maize flowering time variants we evaluated flowering time traits using an extremely large multi- genetic background population that contained more than 8000 l...

  18. Two Test Items to Explore High School Students' Beliefs of Sample Size When Sampling from Large Populations

    ERIC Educational Resources Information Center

    Bill, Anthony; Henderson, Sally; Penman, John

    2010-01-01

    Two test items that examined high school students' beliefs of sample size for large populations using the context of opinion polls conducted prior to national and state elections were developed. A trial of the two items with 21 male and 33 female Year 9 students examined their naive understanding of sample size: over half of students chose a…

  19. Sexual Harassment and Sexual Bulllying (For Teens)

    MedlinePlus

    ... of Healthy Breakfasts Shyness Sexual Harassment and Sexual Bullying KidsHealth > For Teens > Sexual Harassment and Sexual Bullying ... being sexually harassed or bullied. What Are Sexual Bullying and Harassment? Just like other kinds of bullying, ...

  20. Pediatric Weight Management Program Outcomes in a Largely Minority, Low Socioeconomic Status Population

    PubMed Central

    Demeule-Hayes, Michelle; Winters, Matthew W.; Getzoff, Elizabeth A.; Schwimmer, Bradley A.; Rogers, Vicky S.; Scheimann, Ann O.

    2016-01-01

    This article describes the outcomes of a pediatric weight management program for a population primarily composed of minority ethnic groups and those from a lower socioeconomic status group. As these groups are disproportionally affected by pediatric obesity and overweight complicated by higher rates of attrition and poorer response to intervention, it is important that adequate and effective treatment exists for patients in these groups. Further research is needed to analyze the outcomes and attrition in these high-risk populations. PMID:27980446

  1. The Relationship between Parental Opinion of School-Based Sex Education, Parent-Child Communication about Sexuality, and Parenting Styles in a Diverse Urban Community College Population

    ERIC Educational Resources Information Center

    Heller, Janet

    2009-01-01

    One hundred and ninety-one parents attending an urban, community college were surveyed about what topics schools should teach their children about sexuality education, and how they communicate with their child about sexuality topics. The quantitative data was collected using a "School Sexuality Education Questionnaire" (SSEQ), and the "Parenting…

  2. Are Sex Drive and Hypersexuality Associated with Pedophilic Interest and Child Sexual Abuse in a Male Community Sample?

    PubMed

    Klein, Verena; Schmidt, Alexander F; Turner, Daniel; Briken, Peer

    2015-01-01

    Although much is currently known about hypersexuality (in the form of excessive sexual behavior) among sexual offenders, the degree to which hypersexual behavior is linked to paraphilic and especially pedophilic interests in non-forensic populations has not been established.The purpose of the present study was to elucidate the associations between total sexual outlets(TSO) and other sex drive indicators, antisocial behavior, pedophilic interests, and sexual offending behavior in a large population-based community sample of males. The sample included 8,718 German men who participated in an online study. Hypersexual behavior as measured by self-reported TSO, self-reported sex drive, criminal history, and pedophilic interests were assessed. In moderated hierarchical logistic regression analyses self-reported contact sexual offending against children was linked to sexual fantasizing about children and anti sociality.There was no association between aggregated sex drive, and sexual abusive behaviour in the multivariate analyses. In contrast, self-reported child pornography consumption was associated with sex drive, sexual fantasies involving children, and anti sociality. Nevertheless, in convicted sexual offenders anti sociality, sexual preoccupation (like hypersexuality), and pedophilic interest are important predictors of sexual reoffending against prepubescent children.Therefore, in clinical practice an assessment of criminal history and pedophilic interests in hypersexual individuals and vice versa hypersexuality in antisocial or pedophilic men should be considered [corrected].

  3. NASA Orbital Debris Large-Object Baseline Population in ORDEM 3.0

    NASA Technical Reports Server (NTRS)

    Krisco, Paula H.; Vavrin, A. B.; Anz-Meador, P. D.

    2013-01-01

    The NASA Orbital Debris Program Office (ODPO) has created and validated high fidelity populations of the debris environment for the latest Orbital Debris Engineering Model (ORDEM 3.0). Though the model includes fluxes of objects 10 um and larger, this paper considers particle fluxes for 1 cm and larger debris objects from low Earth orbit (LEO) through Geosynchronous Transfer Orbit (GTO). These are validated by several reliable radar observations through the Space Surveillance Network (SSN), Haystack, and HAX radars. ORDEM 3.0 populations were designed for the purpose of assisting, debris researchers and sensor developers in planning and testing. This environment includes a background derived from the LEO-to-GEO ENvironment Debris evolutionary model (LEGEND) with a Bayesian rescaling as well as specific events such as the FY-1C anti-satellite test, the Iridium 33/Cosmos 2251 accidental collision, and the Soviet/Russian Radar Ocean Reconnaissance Satellite (RORSAT) sodium-potassium droplet releases. The environment described in this paper is the most realistic orbital debris population larger than 1 cm, to date. We describe derivations of the background population and added specific populations. We present sample validation charts of our 1 cm and larger LEO population against Space Surveillance Network (SSN), Haystack, and HAX radar measurements.

  4. A Spatio-Temporally Explicit Random Encounter Model for Large-Scale Population Surveys

    PubMed Central

    Jousimo, Jussi; Ovaskainen, Otso

    2016-01-01

    Random encounter models can be used to estimate population abundance from indirect data collected by non-invasive sampling methods, such as track counts or camera-trap data. The classical Formozov–Malyshev–Pereleshin (FMP) estimator converts track counts into an estimate of mean population density, assuming that data on the daily movement distances of the animals are available. We utilize generalized linear models with spatio-temporal error structures to extend the FMP estimator into a flexible Bayesian modelling approach that estimates not only total population size, but also spatio-temporal variation in population density. We also introduce a weighting scheme to estimate density on habitats that are not covered by survey transects, assuming that movement data on a subset of individuals is available. We test the performance of spatio-temporal and temporal approaches by a simulation study mimicking the Finnish winter track count survey. The results illustrate how the spatio-temporal modelling approach is able to borrow information from observations made on neighboring locations and times when estimating population density, and that spatio-temporal and temporal smoothing models can provide improved estimates of total population size compared to the FMP method. PMID:27611683

  5. Population.

    ERIC Educational Resources Information Center

    King, Pat; Landahl, John

    This pamphlet has been prepared in response to a new problem, a rapidly increasing population, and a new need, population education. It is designed to help teachers provide their students with some basic population concepts with stress placed on the elements of decision making. In the first section of the pamphlet, some of the basic concepts of…

  6. [Population].

    PubMed

    1979-01-01

    Data on the population of Venezuela between 1975 and 1977 are presented in descriptive tables and graphs. Information is included on the employed population according to category, sex, and type of economic activity, and by sex, age, and area on the employment rate and the total, the economically active, and the unemployed population.

  7. No evidence for a large difference in ALS frequency in populations of African and European origin: a population based study in inner city London.

    PubMed

    Rojas-Garcia, Ricardo; Scott, Kirsten M; Roche, Jose Carlos; Scotton, William; Martin, Naomi; Janssen, Anna; Goldstein, Laura H; Leigh, P Nigel; Ellis, Cathy M; Shaw, Christopher E; Al-Chalabi, Ammar

    2012-01-01

    Abstract Previous studies have suggested a lower incidence of ALS in people of African origin. We used a population based register in an urban setting from inner city London postcodes where there is a large population of people of African ancestry to compare the frequency of ALS in people of European and African origin. Population statistics stratified by age, gender and ethnicity were obtained from the 2001 census. Incidence and prevalence were calculated in each ethnic group. Results showed that in a population of 683,194, of which 22% were of African ancestry, 88 individuals with ALS were identified over a seven-year period, including 14 people with African ancestry. The adjusted incidence in people of African ancestry was 1.35 per 100,000 person-years (95% CI 0.72-2.3) and in those of European ancestry 1.97 per 100,000 person-years (95% CI 1.55-2.48). In conclusion, in this small population based study we could not detect a difference in rates of ALS between people of African ancestry and those of European ancestry.

  8. Correlates of Sexual Abuse and Smoking among French Adults

    ERIC Educational Resources Information Center

    King, Gary; Guilbert, Philippe; Ward, D. Gant; Arwidson, Pierre; Noubary, Farzad

    2006-01-01

    Objective: The goal of this study was to examine the association between sexual abuse (SA) and initiation, cessation, and current cigarette smoking among a large representative adult population in France. Method: A random sample size of 12,256 adults (18-75 years of age) was interviewed by telephone concerning demographic variables, health…

  9. Study of large and highly stratified population datasets by combining iterative pruning principal component analysis and structure

    PubMed Central

    2011-01-01

    Background The ever increasing sizes of population genetic datasets pose great challenges for population structure analysis. The Tracy-Widom (TW) statistical test is widely used for detecting structure. However, it has not been adequately investigated whether the TW statistic is susceptible to type I error, especially in large, complex datasets. Non-parametric, Principal Component Analysis (PCA) based methods for resolving structure have been developed which rely on the TW test. Although PCA-based methods can resolve structure, they cannot infer ancestry. Model-based methods are still needed for ancestry analysis, but they are not suitable for large datasets. We propose a new structure analysis framework for large datasets. This includes a new heuristic for detecting structure and incorporation of the structure patterns inferred by a PCA method to complement STRUCTURE analysis. Results A new heuristic called EigenDev for detecting population structure is presented. When tested on simulated data, this heuristic is robust to sample size. In contrast, the TW statistic was found to be susceptible to type I error, especially for large population samples. EigenDev is thus better-suited for analysis of large datasets containing many individuals, in which spurious patterns are likely to exist and could be incorrectly interpreted as population stratification. EigenDev was applied to the iterative pruning PCA (ipPCA) method, which resolves the underlying subpopulations. This subpopulation information was used to supervise STRUCTURE analysis to infer patterns of ancestry at an unprecedented level of resolution. To validate the new approach, a bovine and a large human genetic dataset (3945 individuals) were analyzed. We found new ancestry patterns consistent with the subpopulations resolved by ipPCA. Conclusions The EigenDev heuristic is robust to sampling and is thus superior for detecting structure in large datasets. The application of EigenDev to the ipPCA algorithm

  10. Spectrum of large copy number variations in 26 diverse Indian populations: potential involvement in phenotypic diversity.

    PubMed

    Gautam, Pramod; Jha, Pankaj; Kumar, Dhirendra; Tyagi, Shivani; Varma, Binuja; Dash, Debasis; Mukhopadhyay, Arijit; Mukerji, Mitali

    2012-01-01

    Copy number variations (CNVs) have provided a dynamic aspect to the apparently static human genome. We have analyzed CNVs larger than 100 kb in 477 healthy individuals from 26 diverse Indian populations of different linguistic, ethnic and geographic backgrounds. These CNVRs were identified using the Affymetrix 50K Xba 240 Array. We observed 1,425 and 1,337 CNVRs in the deletion and amplification sets, respectively, after pooling data from all the populations. More than 50% of the genes encompassed entirely in CNVs had both deletions and amplifications. There was wide variability across populations not only with respect to CNV extent (ranging from 0.04-1.14% of genome under deletion and 0.11-0.86% under amplification) but also in terms of functional enrichments of processes like keratinization, serine proteases and their inhibitors, cadherins, homeobox, olfactory receptors etc. These did not correlate with linguistic, ethnic, geographic backgrounds and size of populations. Certain processes were near exclusive to deletion (serine proteases, keratinization, olfactory receptors, GPCRs) or duplication (homeobox, serine protease inhibitors, embryonic limb morphogenesis) datasets. Populations having same enriched processes were observed to contain genes from different genomic loci. Comparison of polymorphic CNVRs (5% or more) with those cataloged in Database of Genomic Variants revealed that 78% (2473) of the genes in CNVRs in Indian populations are novel. Validation of CNVs using Sequenom MassARRAY revealed extensive heterogeneity in CNV boundaries. Exploration of CNV profiles in such diverse populations would provide a widely valuable resource for understanding diversity in phenotypes and disease.

  11. Polymorphism analysis of 15 STR loci in a large sample of Guangdong (Southern China) Han population.

    PubMed

    Chen, Ling; Lu, Huijie; Qiu, Pingming; Yang, Xingyi; Liu, Chao

    2015-11-01

    AmpFℓSTR Sinofiler PCR Amplification Kit is specially developed for Chinese forensic laboratories, but there are little population-genetic data about this kit for Southern China. This kit contains 15 STR loci: D8S1179, D21S11, D7S820, CSF1PO, D3S1358, D13S317, D16S539, D2S1338, D19S433, vWA, D18S51, D6S1043, D12S391, D5S818 and FGA. We have conducted genotyping experiments on the 15 STR loci in 5234 unrelated individuals from Guangdong (Southern China). We observed a total of 243 alleles in the group with the allelic frequency values ranging from less than 0.0001 to 0.3686. Our statistic analysis indicates that the 15 STR loci conform to the Hardy-Weinberg's equilibrium (p>0.05). The highest polymorphism was found at D6S1043 locus and the lowest was found at D3S1358. The combined power of discrimination reached 0.99999999999999999977431 and the combined probability of paternity exclusion reached 0.999999721 for 15 STR loci. Guangdong Han population had significant differences compared with Shaanxi, Shandong and Henan province of Northern China. A Neighbor-joining tree indicates that the Guangdong Han has a close genetic relationship with the Yunnan population. Significant differences were found between Guangdong Han population and other reported populations (Japanese, Philippine, African American, Caucasian, Hispanic and Western Romanian) at 2-11 STR loci. The results may provide useful information for forensic sciences and population genetics studies. The present findings indicate that all the 15 STR loci are highly genetically polymorphic in the Han population of Guangdong.

  12. Large-scale structure of brown rat (Rattus norvegicus) populations in England: effects on rodenticide resistance

    PubMed Central

    Haniza, Mohd Z.H.; Adams, Sally; Jones, Eleanor P.; MacNicoll, Alan; Mallon, Eamonn B.; Smith, Robert H.

    2015-01-01

    The brown rat (Rattus norvegicus) is a relatively recent (<300 years) addition to the British fauna, but by association with negative impacts on public health, animal health and agriculture, it is regarded as one of the most important vertebrate pest species. Anticoagulant rodenticides were introduced for brown rat control in the 1950s and are widely used for rat control in the UK, but long-standing resistance has been linked to control failures in some regions. One thus far ignored aspect of resistance biology is the population structure of the brown rat. This paper investigates the role population structure has on the development of anticoagulant resistance. Using mitochondrial and microsatellite DNA, we examined 186 individuals (from 15 counties in England and one location in Wales near the Wales–England border) to investigate the population structure of rural brown rat populations. We also examined individual rats for variations of the VKORC1 gene previously associated with resistance to anticoagulant rodenticides. We show that the populations were structured to some degree, but that this was only apparent in the microsatellite data and not the mtDNA data. We discuss various reasons why this is the case. We show that the population as a whole appears not to be at equilibrium. The relative lack of diversity in the mtDNA sequences examined can be explained by founder effects and a subsequent spatial expansion of a species introduced to the UK relatively recently. We found there was a geographical distribution of resistance mutations, and relatively low rate of gene flow between populations, which has implications for the development and management of anticoagulant resistance. PMID:26664802

  13. The impact of climate change on the bottom up regulation of density dependence in large herbivore populations

    NASA Astrophysics Data System (ADS)

    Ahrestani, F.; Smith, W. A.; Hebblewhite, M.; Running, S. W.; Post, E.

    2013-12-01

    Population dynamics are regulated by either density dependent or, independent (environmental) factors, and climate change may influence populations through either pathway. One key factor in the population dynamics of large herbivores is the dynamics of vegetation nutrient content, which although being an environmental factor, has the potential to impact the degree of density dependence that regulates population dynamics. To understand this bottom up regulatory mechanism and how climate interacts with vegetation, we will estimate the influence of vegetation dynamics on annual abundance estimates of multiple vertebrate populations using time-series analysis. We will test the hypothesis that the strength of density dependence is expected to vary inversely with changes in vegetation availability, i.e., in areas with higher forage abundance and quality, density dependence is expected to be stronger. Extended to climate change, this hypothesis predicts that climate impacts will be stronger in areas of low vegetation availability, such as the arctic and alpine regions. We will analyze a combined dataset of 55 globally distributed Cervus (elk/red deer) and Rangifer (caribou/reindeer) populations that inhabit areas >100km2. These population time-series we will be analyzed using Markov Chain Monte Carlo Bayesian state-space models, and to represent annual vegetation dynamics we will use Global Inventory Monitoring and Modeling System (GIMMS) normalized difference vegetation index (NDVI) data (i.e., third generation GIMMS NDVI from AVHRR sensors).

  14. Phylogeography of competing sexual and parthenogenetic forms of a freshwater flatworm: patterns and explanations

    PubMed Central

    Pongratz, Norbert; Storhas, Martin; Carranza, Salvador; Michiels, Nicolaas K

    2003-01-01

    Background Models of the maintenance of sex predict that one reproductive strategy, sexual or parthenogenetic, should outcompete the other. Distribution patterns may reflect the outcome of this competition as well as the effect of chance and historical events. We review the distribution data of sexual and parthenogenetic biotypes of the planarian Schmidtea polychroa. Results S. polychroa lives in allopatry or sympatry across Europe except for Central and North-Western Europe, where sexual individuals have never been reported. A phylogenetic relationship between 36 populations based on a 385 bp fragment of the mitochondrial cytochrome oxidase I gene revealed that haplotypes were often similar over large geographic distances. In North Italian lakes, however, diversity was extreme, with sequence differences of up to 5% within the same lake in both sexuals and parthenogens. Mixed populations showed "endemic" parthenogenetic lineages that presumably originated from coexisting sexuals, and distantly related ones that probably result from colonization by parthenogens independent from sexuals. Conclusions Parthenogens originated repeatedly from sexuals, mainly in Italy, but the same may apply to other Mediterranean regions (Spain, Greece). The degree of divergence between populations suggests that S. polychroa survived the ice ages in separate ice-free areas in Central, Eastern and Southern Europe and re-colonised Europe after the retreat of the major glaciers. Combining these results with those based on nuclear markers, the data suggest that repeated hybridisation between sexuals and parthenogenetic lineages in mixed populations maintains high levels of genetic diversity in parthenogens. This can explain why parthenogens persist in populations that were originally sexual. Exclusive parthenogenesis in central and western populations suggests better colonisation capacity, possibly because of inbreeding costs as well as hybridisation of sexuals with parthenogens. PMID

  15. Exposure to physical and sexual violence prior to imprisonment predicts mental health and substance use treatments in prison populations.

    PubMed

    Sánchez, Francisco Caravaca; Luna, Aurelio; Mundt, Adrian

    2016-08-01

    The present study aimed to establish rates of exposure to physical or sexual violence (PSV) prior to imprisonment for prisoners in Spain and to explore whether people exposed to PSV access mental health treatment during imprisonment. In a sample of 2484 male and 225 female prisoners, socio-demographic variables, exposure to PSV prior to imprisonment and mental health treatments during imprisonment were assessed. Frequencies were calculated as per cent values with 95% confidence intervals (CI). The Risk Ratio (RR) of PSV and other socio-demographic variables to associate with mental health treatment during imprisonment was established. History of PSV was present in 35.2% (95% CI: 33.3-37.0) of the male and 40.0% (95% CI: 33.9-46.8) of the female prisoners. 70.7% (95% CI: 67.8-73.9) of the male and 76.9% (95% CI: 67.7-86.0) of the female prisoners with prior exposure to PSV were in mental health treatment during imprisonment. PSV was a significant predictor of mental health treatment during imprisonment in male (RR: 2.79; 95% CI 2.44-2.92) and female (RR: 1.94; 95% CI 1.76-2.23) prisoners. Most people with exposure to PSV prior to imprisonment access mental health treatment during imprisonment. Treatments may have to focus more on traumatic experiences.

  16. Self-reported and agency-notified child sexual abuse in a population-based birth cohort

    PubMed Central

    Kisely, Steve; Alati, Rosa; Strathearn, Lane; Najman, Jake

    2016-01-01

    Child sexual abuse (CSA) has been associated with many adverse psychiatric outcomes. However, most studies have relied on retrospective self-report of exposure to CSA. We set out to investigate the incidence of CSA in the same birth cohort using both retrospective self-report and prospective government agency notification, and examine the psychological outcomes in young adulthood. The primary outcomes were measures of DSM-IV diagnoses (CIDI-Auto) at age 21. The 21-year retrospective CSA questions were completed by 3739 participants. CSA was self-reported by 19.3% of males and 30.6% of females. After adjustment for potential confounders, both self-reported and agency-notified CSA were associated with increased odds of lifetime major depressive disorder (MDD), anxiety disorders, and posttraumatic stress disorder (PTSD). For the first time in a birth cohort, this study has shown the disparity between the incidence of CSA when measured by self-report and government agency notification. Despite this discrepancy, adverse psychiatric outcomes are seen when CSA is defined using either method. PMID:26774419

  17. Stem cells from innate sexual but not acquired sexual planarians have the capability to form a sexual individual.

    PubMed

    Nodono, Hanae; Ishino, Yugo; Hoshi, Motonori; Matsumoto, Midori

    2012-11-01

    Planarian species may harbor as many as three populations with different reproductive strategies. Animals from innate asexual (AS) and innate sexual (InS) populations reproduce only by fission and cross-fertilization, respectively, whereas the third population switches seasonally between the two reproductive modes. AS worms can be experimentally sexualized by feeding them with minced InS worms; we termed the resulting animals "acquired sexual" (AqS) worms. Both AqS and InS worms exhibit sexualizing activity when used as feed, suggesting that they maintain their sexual state via endogenous sexualizing substances, although the mechanisms underlying determination of reproductive strategy and sexual switching in these metazoans remain enigmatic. Therefore, we compared the endogenous sexualizing activity of InS worms and AqS worms. First, we amputated mature worms and assessed if they could re-enter a sexual state. Regenerants of InS worms, but not AqS worms, were only sexual, indicating that sexual state regulation comprises two steps: (1) autonomous initiation of sexualizing substance production and (2) maintenance of the sexual state by continuous production of sexualizing substances. Next, InS neoblasts were characterized by transplantation, finding that they successfully engrafted, proliferated, and replaced all recipient cells. Under such conditions, the AS recipients of InS worm neoblasts, but not those of AqS worms, became sexual. These results clearly show that there is a neoblast-autonomous determination of reproductive strategy in planarians.

  18. Evolution and human sexuality.

    PubMed

    Gray, Peter B

    2013-12-01

    The aim of this review is to put core features of human sexuality in an evolutionary light. Toward that end, I address five topics concerning the evolution of human sexuality. First, I address theoretical foundations, including recent critiques and developments. While much traces back to Darwin and his view of sexual selection, more recent work helps refine the theoretical bases to sex differences and life history allocations to mating effort. Second, I consider central models attempting to specify the phylogenetic details regarding how hominin sexuality might have changed, with most of those models honing in on transitions from a possible chimpanzee-like ancestor to the slightly polygynous and long-term bonded sociosexual partnerships observed among most recently studied hunter-gatherers. Third, I address recent genetic and physiological data contributing to a refined understanding of human sexuality. As examples, the availability of rapidly increasing genomic information aids comparative approaches to discern signals of selection in sexuality-related phenotypes, and neuroendocrine studies of human responses to sexual stimuli provide insight into homologous and derived mechanisms. Fourth, I consider some of the most recent, large, and rigorous studies of human sexuality. These provide insights into sexual behavior across other national samples and on the Internet. Fifth, I discuss the relevance of a life course perspective to understanding the evolution of human sexuality. Most research on the evolution of human sexuality focuses on young adults. Yet humans are sexual beings from gestation to death, albeit in different ways across the life course, and in ways that can be theoretically couched within life history theory.

  19. Genetic population structure of Gyrodactylus thymalli (Monogenea) in a large Norwegian river system.

    PubMed

    Pettersen, Ruben Alexander; Mo, Tor Atle; Hansen, Haakon; Vøllestad, Leif Asbjørn

    2015-12-01

    The extent of geographic genetic variation is the result of several processes such as mutation, gene flow, selection and drift. Processes that structure the populations of parasite species are often directly linked to the processes that influence the host. Here, we investigate the genetic population structure of the ectoparasite Gyrodactylus thymalli Žitňan, 1960 (Monogenea) collected from grayling (Thymallus thymallus L.) throughout the river Glomma, the largest watercourse in Norway. Parts of the mitochondrial dehydrogenase subunit 5 (NADH 5) and cytochrome oxidase I (COI) genes from 309 G. thymalli were analysed to study the genetic variation and investigated the geographical distribution of parasite haplotypes. Three main clusters of haplotypes dominated the three distinct geographic parts of the river system; one cluster dominated in the western main stem of the river, one in the eastern and one in the lower part. There was a positive correlation between pairwise genetic distance and hydrographic distance. The results indicate restricted gene flow between sub-populations of G. thymalli, most likely due to barriers that limit upstream migration of infected grayling. More than 80% of the populations had private haplotypes, also indicating long-time isolation of sub-populations. According to a molecular clock calibration, much of the haplotype diversity of G. thymalli in the river Glomma has developed after the last glaciation.

  20. Relations between anthropometric parameters and sexual activity of Hungarian men.

    PubMed

    Rurik, I; Szigethy, E; Fekete, F; Langmár, Z

    2012-01-01

    In the last decades, there were visible achievements in the evaluation of sexuality-related problems and issues regarding sexual life. However, there are limited reliable and comparable data on the average values of sexual activity and its relation to anthropometric parameters in different populations and age cohorts. This study tries to examine the association between anthropometric parameters and male sexual activity. A clinical population of 1146 male patients between 25 and 45 years of age attending an outpatient clinic of andrology in Budapest (Hungary) was examined and questioned in a medical setting. Age, body height, weight, body mass index (BMI) and self-reported sexual activity were the main outcome measures. The patients were allotted into age groups (25-29, 30-39 and 40-45 years), the youngest group showing the highest coital activity. Although obesity and overweight were present in 61% of the study population, no connections between BMI and sexual activity were apparent. Comparing less active persons with those reporting at least two intercourses per week, significant difference was found between body height groups. Men below 170 cm reported higher activity than men over 180 cm. Despite the fact that the prevalence of obesity among younger generations is increasing, it has had no visible influence on the sexual activity of this age cohort as yet. Our data suggest that sexual activity was not clearly related to other anthropometric parameters, and depends mainly on the characteristics of the population examined. There is a great need for large-scale studies worldwide on larger representative samples, using similar methods, to acquire reliable data from other nations and different age groups.

  1. Does developmental timing of exposure to child maltreatment predict memory performance in adulthood? Results from a large, population-based sample.

    PubMed

    Dunn, Erin C; Busso, Daniel S; Raffeld, Miriam R; Smoller, Jordan W; Nelson, Charles A; Doyle, Alysa E; Luk, Gigi

    2016-01-01

    Although maltreatment is a known risk factor for multiple adverse outcomes across the lifespan, its effects on cognitive development, especially memory, are poorly understood. Using data from a large, nationally representative sample of young adults (Add Health), we examined the effects of physical and sexual abuse on working and short-term memory in adulthood. We examined the association between exposure to maltreatment as well as its timing of first onset after adjusting for covariates. Of our sample, 16.50% of respondents were exposed to physical abuse and 4.36% to sexual abuse by age 17. An analysis comparing unexposed respondents to those exposed to physical or sexual abuse did not yield any significant differences in adult memory performance. However, two developmental time periods emerged as important for shaping memory following exposure to sexual abuse, but in opposite ways. Relative to non-exposed respondents, those exposed to sexual abuse during early childhood (ages 3-5), had better number recall and those first exposed during adolescence (ages 14-17) had worse number recall. However, other variables, including socioeconomic status, played a larger role (than maltreatment) on working and short-term memory. We conclude that a simple examination of "exposed" versus "unexposed" respondents may obscure potentially important within-group differences that are revealed by examining the effects of age at onset to maltreatment.

  2. Does developmental timing of exposure to child maltreatment predict memory performance in adulthood? Results from a large, population-based sample

    PubMed Central

    Dunn, Erin C.; Busso, Daniel S.; Raffeld, Miriam R.; Smoller, Jordan W.; Nelson, Charles A.; Doyle, Alysa E.; Luk, Gigi

    2015-01-01

    Although maltreatment is a known risk factor for multiple adverse outcomes across the lifespan, its effects on cognitive development, especially memory, are poorly understood. Using data from a large, nationally representative sample of young adults (Add Health), we examined the effects of physical and sexual abuse on working and short-term memory in adulthood. We examined the association between exposure to maltreatment as well as its timing of first onset after adjusting for covariates. Of our sample, 16.50% of respondents were exposed to physical abuse and 4.36 % to sexual abuse by age 17. An analysis comparing unexposed respondents to those exposed to physical or sexual abuse did not yield any significant differences in adult memory performance. However, two developmental time periods emerged as important for shaping memory following exposure to sexual abuse, but in opposite ways. Relative to non-exposed respondents, those exposed to sexual abuse during early childhood (ages 3-5), had better number recall and those first exposed during adolescence (ages 14-17) had worse number recall. However, other variables, including socioeconomic status, played a larger role (than maltreatment) on working and short-term memory. We conclude that a simple examination of “exposed” versus “unexposed” respondents may obscure potentially important within-group differences that are revealed by examining the effects of age at onset to maltreatment. PMID:26585216

  3. Masters Swimmers Use More Dietary Supplements Than a Large National Comparison Population in the United States.

    PubMed

    Guthrie, Sally K; Erickson, Steven R

    2016-04-01

    The use of dietary supplements was compared between a cohort of committed exercisers, U.S. Masters Swimming (USMS) members (n = 1,042), and the general U.S. population, exemplified by respondents to the National Health and Nutrition Examination Survey (NHANES) from 2009 to 2010 (n = 6,209). USMS swimmers were significantly more likely to take dietary supplements (62%) than the general U.S. adult population, as represented by the NHANES population (37%). Those taking dietary supplements were older, more likely to be female and Caucasian, and more highly educated and affluent than those not taking supplements (p < .001 for all). When adjusted for age, race, gender, annual income, and education, masters swimmers were still more likely (p < .001) to use dietary supplements than the NHANES cohort. In addition, masters swimmers were significantly more likely (p < .001) to use either creatine or dehydroepiandrosterone or testosterone than those in the NHANES cohort.

  4. Predictors of Toxoplasma gondii infection in Czech and Slovak populations: the possible role of cat-related injuries and risky sexual behavior in the parasite transmission.

    PubMed

    Flegr, J

    2017-02-10

    The protozoan Toxoplasma gondii infects about