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1

Rate of Adaptation in Large Sexual Populations  

PubMed Central

Adaptation often involves the acquisition of a large number of genomic changes that arise as mutations in single individuals. In asexual populations, combinations of mutations can fix only when they arise in the same lineage, but for populations in which genetic information is exchanged, beneficial mutations can arise in different individuals and be combined later. In large populations, when the product of the population size N and the total beneficial mutation rate Ub is large, many new beneficial alleles can be segregating in the population simultaneously. We calculate the rate of adaptation, v, in several models of such sexual populations and show that v is linear in NUb only in sufficiently small populations. In large populations, v increases much more slowly as log NUb. The prefactor of this logarithm, however, increases as the square of the recombination rate. This acceleration of adaptation by recombination implies a strong evolutionary advantage of sex. PMID:19948891

Neher, R. A.; Shraiman, B. I.; Fisher, D. S.

2010-01-01

2

Genetic Draft and Quasi-Neutrality in Large Facultatively Sexual Populations  

PubMed Central

Large populations may contain numerous simultaneously segregating polymorphisms subject to natural selection. Since selection acts on individuals whose fitness depends on many loci, different loci affect each other’s dynamics. This leads to stochastic fluctuations of allele frequencies above and beyond genetic drift—an effect known as genetic draft. Since recombination disrupts associations between alleles, draft is strong when recombination is rare. Here, we study a facultatively outcrossing population in a regime where the frequency of outcrossing and recombination, r, is small compared to the characteristic scale of fitness differences ?. In this regime, fit genotypes expand clonally, leading to large fluctuations in the number of recombinant offspring genotypes. The power law tail in the distribution of the latter makes it impossible to capture the dynamics of draft by an effective neutral model. Instead, we find that the fixation time of a neutral allele increases only slowly with the population size but depends sensitively on the ratio r/?. The efficacy of selection is reduced dramatically and alleles behave “quasi-neutrally” even for Ns?1, provided that |s| < sc, where sc depends strongly on r/?, but only weakly on population size N. In addition, the anomalous fluctuations due to draft change the spectrum of (quasi)-neutral alleles from f(?) ? ??1, corresponding to drift, to ? ??2. Finally, draft accelerates the rate of two-step adaptations through deleterious intermediates. PMID:21625002

Neher, R. A.; Shraiman, B. I.

2011-01-01

3

Emergence of clones in sexual populations  

NASA Astrophysics Data System (ADS)

In sexual population, recombination reshuffles genetic variation and produces novel combinations of existing alleles, while selection amplifies the fittest genotypes in the population. If recombination is more rapid than selection, populations consist of a diverse mixture of many genotypes, as is observed in many populations. In the opposite regime, which is realized for example in the facultatively sexual populations that outcross in only a fraction of reproductive cycles, selection can amplify individual genotypes into large clones. Such clones emerge when the fitness advantage of some of the genotypes is large enough that they grow to a significant fraction of the population despite being broken down by recombination. The occurrence of this ‘clonal condensation’ depends, in addition to the outcrossing rate, on the heritability of fitness. Clonal condensation leads to a strong genetic heterogeneity of the population which is not adequately described by traditional population genetics measures, such as linkage disequilibrium. Here we point out the similarity between clonal condensation and the freezing transition in the random energy model of spin glasses. Guided by this analogy we explicitly calculate the probability, Y, that two individuals are genetically identical as a function of the key parameters of the model. While Y is the analog of the spin-glass order parameter, it is also closely related to rate of coalescence in population genetics: two individuals that are part of the same clone have a recent common ancestor.

Neher, Richard A.; Vucelja, Marija; Mezard, Mark; Shraiman, Boris I.

2013-01-01

4

Causes of male sexual trait divergence in introduced populations of guppies  

PubMed Central

Males from different populations of the same species often differ in their sexually selected traits. Variation in sexually selected traits can be attributed to sexual selection if phenotypic divergence matches the direction of sexual selection gradients among populations. However, phenotypic divergence of sexually selected traits may also be influenced by other factors, such as natural selection and genetic constraints. Here, we document differences in male sexual traits among six introduced Australian populations of guppies and untangle the forces driving divergence in these sexually selected traits. Using an experimental approach, we found that male size, area of orange coloration, number of sperm per ejaculate and linear sexual selection gradients for male traits differed among populations. Within populations, a large mismatch between the direction of selection and male traits suggests that constraints may be important in preventing male traits from evolving in the direction of selection. Among populations, however, variation in sexual selection explained more than half of the differences in trait variation, suggesting that, despite within-population constraints, sexual selection has contributed to population divergence of male traits. Differences in sexual traits were also associated with predation risk and neutral genetic distance. Our study highlights the importance of sexual selection in trait divergence in introduced populations, despite the presence of constraining factors such as predation risk and evolutionary history. PMID:24456226

Lindholm, A K; Head, M L; Brooks, R C; Rollins, L A; Ingleby, F C; Zajitschek, S R K

2014-01-01

5

Development of Populations 177 6.6 Growth of Populations with Sexual Reproduction  

E-print Network

Development of Populations 177 6.6 Growth of Populations with Sexual Reproduction G. Alsmeyer In Section 5.9, we studied the effect of sexual reproduction on criticality and ex- tinction risk-negative Alsmeyer G (2005). Growth of Populations with Sexual Reproduction. In: Branching Processes: Variation

Alsmeyer, Gerold

6

Natural and sexual selection in a monogamous historical human population  

E-print Network

Natural and sexual selection in a monogamous historical human population Alexandre Courtiola,b,c,1 selection in natural populations are well established, our understanding of selection in humans has been of natural and sexual selection in humans that includes the effects of sex and wealth on different episodes

Lummaa, Virpi

7

The genetic structure of populations of sexual and asexual Taraxacum (dandelions)  

Microsoft Academic Search

The genetic structure, as assessed by isozymes, is described for three populations of outbreeding sexuals, three populations of obligate agamosperms, and six accessions of inbreeding sexual Taraxacum. Fifteen loci in 10 isozyme systems were identified, and isozyme bands were previously shown to be allelic in sexual × sexual and were confirmed as allelic in sexual × agamosperm crosses. Sexual ×

Jane Hughes; A J Richards

1988-01-01

8

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

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…

Steel, Jennifer L.; Herlitz, Claes A.

2005-01-01

9

Spreading of sexually transmitted diseases in heterosexual populations  

E-print Network

Disease spreading is a topical issue in a variety of fields ranging from computer viruses in the Internet to air-borne (e.g. influenza) diseases in societies. In particular, the description of the spread of sexually transmitted diseases (Chlamydia, Syphilis, Gonorrhea, AIDS) across population constitutes a major concern for scientists and health agencies. In this context, both data collection on sexual contact networks and the modeling of disease spreading are intensively contributing to the search for effective immunization policies. Here, the spread of sexually transmitted diseases on bipartite scale-free graphs, representing heterosexual contact networks, is considered. We analytically derive the expression for the epidemic threshold and its dependence with the system size in finite populations. The results indicate that in finite bipartite populations with degree distribution as those found in national surveys of sexual attitudes, the onset of the epidemic outbreak takes place for larger spreading rates t...

Gómez-Gardenes, J; Moreno, Y; Profumo, E V

2007-01-01

10

Sexual isolation and mating propensity among allopatric Drosophila mettleri populations.  

PubMed

Drosophila mettleri is found in deserts of North America breeding in soil soaked by the juices of necrotic cacti. Saguaro (Carnegiea gigantea) and cardón (Pachycereus pringlei) are the usual host cacti in Mexico and Arizona, while prickly pear (Opuntia spp.) is used by an isolated population on Santa Catalina Island off the southern California Coast. Populations of D. mettleri show significant local genetic differentiation, especially when geographical isolation is coupled with host shifts. We tested for evidence of sexual isolation among allopatric populations of D. mettleri using a variety of choice and no-choice tests. Populations exhibited significant differences in mating propensity, which translated into significant deviations from random mating. While in some cases these deviations were consistent with sexual isolation, in others, negative assortative mating was observed. No relationship between degree of genetic differentiation and the appearance of sexual isolation was detected. PMID:18561017

Castrezana, Sergio J; Markow, Therese Ann

2008-07-01

11

Disassortative sexual mixing among migrant populations in The Netherlands: a potential for HIV/STI transmission?  

PubMed

To gain insight into the transmission of HIV and sexually transmitted infection (STI) among large migrant groups in The Netherlands, we studied the associations between their demographic and sexual characteristics, in particular condom use, and their sexual mixing patterns with other ethnic groups. In 2002-2005, cross-sectional surveys were conducted among migrants from Surinam (Afro- and Hindo-), the Netherlands Antilles, Cape Verde, and Ghana at social venues in three large cities. A questionnaire was administrated and a saliva sample was collected for HIV antibody testing. Of 2105 migrants recruited, 1680 reported sexual contacts, of whom 41% mixed sexually with other ethnicities, including the indigenous Dutch population. Such disassortative mixing was associated with being second-generation migrant, having several sexual partners, and having a steady and concurrent casual partner. Less disassortative mixing occurred in participants reporting visiting the country of origin. The association between condom use and sexual mixing differed by gender, with men using condoms inconsistently being most likely to be mixing with the Dutch indigenous population. HIV infection and recent STI treatment were not associated with disassortative mixing. This study shows substantial sexual mixing among migrant groups. Since disassortative mixing is more prevalent in second-generation migrants, it might increase in the upcoming years. The mixing patterns in relation to concurrency and the reported condom use in this study suggest a possibly increased level of HIV/STI transmission not only within migrant groups but also between migrant groups, especially via men who mix with the indigenous population and via migrant women who mix with non-Dutch casual partners. Although the observed HIV prevalence in migrants (0.6%) is probably too low to lead to much HIV transmission between ethnicity groups, targeted prevention measures are needed to prevent transmission of other STI. PMID:19806484

van Veen, M G; Kramer, M A; Op de Coul, E L M; van Leeuwen, A P; de Zwart, O; van de Laar, M J W; Coutinho, R A; Prins, M

2009-06-01

12

Spreading of sexually transmitted diseases in heterosexual populations  

PubMed Central

The spread of sexually transmitted diseases (e.g., chlamydia, syphilis, gonorrhea, HIV, etc.) across populations is a major concern for scientists and health agencies. In this context, both the data collection on sexual contact networks and the modeling of disease spreading are intensive contributions to the search for effective immunization policies. Here, the spreading of sexually transmitted diseases on bipartite scale-free graphs, representing heterosexual contact networks, is considered. We analytically derive the expression for the epidemic threshold and its dependence with the system size in finite populations. We show that the epidemic outbreak in bipartite populations, with number of sexual partners distributed as in empirical observations from national sex surveys, takes place for larger spreading rates than for the case in which the bipartite nature of the network is not taken into account. Numerical simulations confirm the validity of the theoretical results. Our findings indicate that the restriction to crossed infections between the two classes of individuals (males and females) has to be taken into account in the design of efficient immunization strategies for sexually transmitted diseases. PMID:18212127

Gómez-Gardeñes, Jesús; Latora, Vito; Moreno, Yamir; Profumo, Elio

2008-01-01

13

Population genetic consequences of extreme variation in sexual and clonal reproduction in an aquatic plant.  

PubMed

Most plants combine sexual reproduction with asexual clonal reproduction in varying degrees, yet the genetic consequences of reproductive variation remain poorly understood. The aquatic plant Butomus umbellatus exhibits striking reproductive variation related to ploidy. Diploids produce abundant viable seed whereas triploids are sexually sterile. Diploids also produce hundreds of tiny clonal bulbils, whereas triploids exhibit only limited clonal multiplication through rhizome fragmentation. We investigated whether this marked difference in reproductive strategy influences the diversity of genotypes within populations and their movement between populations by performing two large-scale population surveys (n = 58 populations) and assaying genotypic variation using random amplified polymorphic DNA (RAPDs). Contrary to expectations, sexually fertile populations did not exhibit higher genotypic diversity than sterile populations. For each cytotype, we detected one very common and widespread genotype. This would only occur with a very low probability (< 10-7) under regular sexual recombination. Compatibility analysis also indicated that the pattern of genotypic variation largely conformed to that expected with predominant clonal reproduction. The potential for recombination in diploids is not realized, possibly because seeds are outcompeted by bulbils for safe sites during establishment. We also failed to find evidence for more extensive movement of fertile than sterile genotypes. Aside from the few widespread genotypes, most were restricted to single populations. Genotypes in fertile populations were very strongly differentiated from those in sterile populations, suggesting that new triploids have not arisen during the colonization of North America. The colonization of North America involves two distinct forms of B. umbellatus that, despite striking reproductive differences, exhibit largely clonal population genetic structures. PMID:12535085

Eckert, Christopher G; Lui, Keiko; Bronson, Kelly; Corradini, Pierre; Bruneau, Anne

2003-02-01

14

Honesty, Perception and Population Divergence in Sexually Selected Traits  

Microsoft Academic Search

We investigate the evolution of female preference for one and two male ornaments, to address two issues in sexual selection: (i) what factors affect the evolution of female preferences; and (ii) how do preferences diverge between isolated populations, leading to speciation? We assume that the male traits are costly indicators of male condition (`handicaps'), and that females benefit directly from

Dolph Schluter; Trevor Price

1993-01-01

15

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

PubMed

The aim of the study was to determine the differences in sexual behaviour and condom use as a protection against sexually transmitted infections (STI) between the first-year and the last-year students. Data were collected by filling anonymous and consented questionnaire in June of 2011 at University of Josip Juraj Strossmayer in Osijek, Croatia. Out of 857 students in the planned sample, 462 (53.9%) filled out the questionnaire, and 353/462 (76.4%) were sexually active. Data from sexually active students were processed and statistically significant results between first-year and the last-year students were presented. Studied sample consisted of 192/353 (54.4%) first-year students and 161/353 (45.6%) last-year students. Average age of sexual initiation for the first-year students was 17.28 +/- 1.29 years, a for the last-year students 18.45 +/- 2.14 years, and the difference is significant (Man-Whitney test = 10335.00, p < 0.01). First-year students have lower number of sexual partners (chi2 = 28.005, p < 0.01), during relationship they had lower number of intercourses with the third person (2 = 17.947, p < 0.01), and feel that lower number of their friends were already sexually active at the time of their own sexual initiation (chi2 = 18.350, p < 0.01). First-year students more often inform their partners about existing or previous STI (chi2 = 14.476, p < 0.01) and curiosity significantly influenced their decision regarding sexual initiation (chi2 = 8.689, p < 0.05). First-year students more often used condom at their first sexual intercourse (chi2 = 7.275, p < 0.01), and more rarely used withdrawal (chi2 = 6.380, p < 0.05). At their last sexual intercourse, first-year students more often used any kind of protection (chi2 = 3.853, p < 0.05),more often used condom (chi2 = 11.110, p < 0.01) and withdrawal (chi2 = 5.156, p < 0.05), and more rarely used contraceptive pills (chi2 = 4.405, p < 0.05). First-year students more often use condom in a permanent relationship (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. PMID:24851594

Dijani?, Tomislav; Kozul, Karlo; Miskulin, Maja; Medi?, Alan; Jurcev-Savicevi?, Anamarija; Burazin, Jelena

2014-03-01

16

Sexuality, Contraception and Pregnancy in a High-School Population  

PubMed Central

Students in a middle-class and in an economically lower-class high school were surveyed regarding their attitudes and behavior with respect to sexuality, contraception, and pregnancy. A large majority of students approved of premarital intercourse for both sexes within the context of a loving relationship. The most important deterrent to sexual intercourse was fear of pregnancy. A majority of both sexes had had sexual intercourse. Forty percent of the sexually active had used no contraception on some occasions, and many of the remainder had used poor methods such as withdrawal or rhythm. The pregnancy rate was high—at least 20 percent in several of the sexually active subgroups. Parents were an infrequent source of information about sex. On the other hand, there was some evidence that students exposed to a sex education program retained useful information if it was relevant to their situation, and if they were appropriately motivated. A model for integrating the various aspects of this subject area is offered. PMID:4726947

Miller, Warren B.

1973-01-01

17

Mutation load and the extinction of large populations  

NASA Astrophysics Data System (ADS)

In the time evolution of finite populations, the accumulation of harmful mutations in further generations might lead to a temporal decay in the mean fitness of the whole population that, after sufficient time, would reduce population size and so lead to extinction. This joint action of mutation load and population reduction is called Mutational Meltdown and is usually considered only to occur in small asexual or very small sexual populations. However, the problem of extinction cannot be discussed in a proper way if one previously assumes the existence of an equilibrium state, as initially discussed in this paper. By performing simulations in a genetically inspired model for time-changing populations, we show that mutational meltdown also occurs in large asexual populations and that the mean time to extinction is a nonmonotonic function of the selection coefficient. The stochasticity of the extinction process is also discussed. The extinction of small sexual N ? 700 populations is shown and our results confirm the assumption that the existence of recombination might be a powerful mechanism to avoid extinction.

Bernardes, A. T.

1996-02-01

18

Natural and sexual selection in a monogamous historical human population  

PubMed Central

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

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

2012-01-01

19

Natural and sexual selection in a monogamous historical human population.  

PubMed

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

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

2012-05-22

20

Associations Between Early First Sexual Intercourse and Later Sexual and Reproductive Outcomes: A Systematic Review of Population-Based Data.  

PubMed

The assumption that early sexual debut leads to adverse outcomes has been used as justification for sexual health interventions and policies aimed at delaying sexual initiation, yet research in the area has been limited. This review identified and synthesized published literature on the association between early first sexual intercourse and later sexual/reproductive outcomes. Literature searches were conducted in Medline, Embase, PsycINFO, and Current Contents. In all, 65 citations met the selection criteria (industrialized, population-based studies). By far the most common sexual behavior to have been investigated has been sexual partners. Studies consistently reported early first intercourse to be associated with more recent, lifetime, and concurrent sexual partners. Early initiators were also more likely to participate in a wider range of sexual practices and report increased sexual satisfaction (among men). Furthermore, early first intercourse, in some studies, was shown to increase the risk of teen pregnancies, teen births, and having an abortion, while findings on STIs and contraceptive use have been mixed. These findings, however, must be interpreted with caution due to methodological problems and limitations present in the research, including a lack of consensus on what constitutes early sexual intercourse and inconsistencies and problems with analyses. PMID:25425161

Heywood, Wendy; Patrick, Kent; Smith, Anthony M A; Pitts, Marian K

2014-11-26

21

High variation in clonal vs. sexual reproduction in populations of the wild strawberry, Fragaria virginiana (Rosaceae)  

E-print Network

was characterized in three populations of the wild strawberry, Fragaria virginiana, to determine the extent, Fragaria virginiana, microsatellites, population genetic structure. INTRODUCTION Many plant speciesHigh variation in clonal vs. sexual reproduction in populations of the wild strawberry, Fragaria

Ashley, Mary V.

22

HIV, Sexual Violence and Special Populations: Adolescence and Pregnancy  

PubMed Central

The risk of male to female transmission of HIV is impacted by baseline inflammation in the female genital tract, semen viral load and seminal plasma’s ability to induce specific patterns of cervical cytokine signalling and influx of immune cell populations. Disruption of the epithelial barrier during non-consensual intercourse may trigger further inflammation and initiation of cell-signalling pathways, thus facilitating transmission of HIV and expansion of local infection. Adolescent and pregnant women are at high risk for sexual violence and may exhibit alterations of genital mucosal immunity that promote immune activation, making them uniquely vulnerable to HIV acquisition. PMID:23176128

Madan, Rebecca Pellett; Herold, Betsy C.

2013-01-01

23

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

PubMed

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

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

2013-01-01

24

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

PubMed Central

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

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

2013-01-01

25

Adolescent sexuality in Asia: new focus for population policy.  

PubMed

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. PMID:12315866

Robey, B

1989-09-01

26

Severely reduced sexual reproduction in northern populations of a clonal plant, Decodon verticillatus (Lythraceae)  

Microsoft Academic Search

Summary 1 In flowering plants the balance between sexual and clonal, asexual reproduction can vary widely. We quantified variation in sexual reproduction in a tristylous, clonal, aquatic plant, Decodon verticillatus , and investigated the role of ecological and genetic factors in causing this variation. 2 We surveyed components of sexual fertility and vegetative growth in 28 populations distributed along a

Marcel E. Dorken; CHRISTOPHER G. ECKERT

2001-01-01

27

Sexual dimorphism of human sternum in a contemporary spanish population.  

PubMed

Sex estimation is one of the first steps in forensic anthropology to identify human remains. In absence of the skull or the pelvis, any skeletal remain becomes fundamental for identification, especially in mass-disaster cases. The sternum is a potentially useful element in anthropological analysis with a high recovery rate in both forensic-and archaeological context. This study aims to develop classification functions for use in Spanish population. For this, sternum sexual dimorphism is studied in a sample of 105 individuals, known age-at-death, ancestry and sex, from San José Municipal Cemetery of Granada (Spain). Lin's concordance correlation coefficient was used to estimate intra-and inter-observer error. In discriminant analysis for estimating sex, cross-validation shows accuracy rates exceeds 90% for sternum body length and maximum width (91.8%), or total length with maximum width (90.7%). Isolated variables with higher accuracy rates are total sternum length (89.1%), and sternum body length (87%). Although there is compliance with Hyrtl's law it is not useful for estimating sex in Spanish population. These discriminant functions have also been validated successfully in two samples from Portugal (Coimbra identified skeletal collection - CISC, and 21st century identified ckeletal collection - Santarém XXI): the variables with higher accuracy rates sternum total length with its maximum width (92.3% the correctly classified individual in the sample CISC; and 83.5% in the sample of Santarém XXI) and the sternum total length (92.1% and 78.5%, respectively). The discriminant functions achieved with the collection of the San Jose cemetery of Granada can be applied to current remains, provided that study populations present a similar sexual dimorphism, like the two samples from Portuguese population presented in this study. PMID:25102779

García-Parra, Patricia; Pérez Fernández, Angela; Djorojevic, Mirjana; Botella, Miguel; Alemán, Inmaculada

2014-11-01

28

Sexually Coercive Behavior in Male Youth: Population Survey of General and Specific Risk Factors  

Microsoft Academic Search

Little is known about risk\\/protective factors for sexually coercive behavior in general population youth. We used a Swedish\\u000a school-based population survey of sexual attitudes and experiences (response rate 77%) and investigated literature-based variables\\u000a across sexually coercive (SEX), non-sexual conduct problem (CP), and normal control (NC) participants to identify general\\u000a and specific risk\\/protective factors for sexual coercion. Among 1,933 male youth,

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

2010-01-01

29

Sexual arousal as a function of physiological and cognitive variables in a sexual offender population  

Microsoft Academic Search

Physiological and cognitive variables may compromise the physiological assessment of sexual arousal, particularly in forensic settings. Thus, the effects of physiological and cognitive variables as potential moderators need investigation with respect to physiological measures of sexual arousal. Penile erection, demographic, and psychometric data were analyzed among 169 inpatient adult male sexual offenders. The hypotheses that (i) sexual arousability would be

Gordon C. Nagayama Hall

1991-01-01

30

Sexual Reproduction in a Simple Growth Population Model  

NASA Astrophysics Data System (ADS)

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.

Lemos, Carlos Gentil Oro; Santos, Marcio

2012-05-01

31

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

PubMed

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. PMID:19888644

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

2010-10-01

32

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

PubMed

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. PMID:22621466

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

2012-01-01

33

Population genetics of Wolbachia-infected, parthenogenetic and uninfected, sexual populations of Tetrastichus coeruleus (Hymenoptera: Eulophidae).  

PubMed

Wolbachia are endosymbiotic bacteria known to manipulate the reproduction of their hosts. These manipulations are expected to have consequences on the population genetics of the host, such as heterozygosity levels, genetic diversity and gene flow. The parasitoid wasp Tetrastichus coeruleus has populations that are infected with parthenogenesis-inducing Wolbachia and populations that are not infected. We studied the population genetics of T. coeruleus between and within Wolbachia-infected and uninfected populations, using nuclear microsatellites and mitochondrial DNA. We expected reduced genetic diversity in both DNA types in infected populations. However, migration and gene flow could introduce new DNA variants into populations. We therefore paid special attention to individuals with unexpected (genetic) characteristics. Based on nuclear and mitochondrial DNA, two genetic clusters were evident: a thelytokous cluster containing all Wolbachia-infected, parthenogenetic populations and an arrhenotokous cluster containing all uninfected, sexual populations. Nuclear and mitochondrial DNA did not exhibit concordant patterns of variation, although there was reduced genetic diversity in infected populations for both DNA types. Within the thelytokous cluster, there was nuclear DNA variation, but no mitochondrial DNA variation. This nuclear DNA variation may be explained by occasional sex between infected females and males, by horizontal transmission of Wolbachia, and/or by novel mutations. Several females from thelytokous populations were uninfected and/or heterozygous for microsatellite loci. These unexpected characteristics may be explained by migration, by inefficient transmission of Wolbachia, by horizontal transmission of Wolbachia, and/or by novel mutations. However, migration has not prevented the build-up of considerable genetic differentiation between thelytokous and arrhenotokous populations. PMID:23879258

Reumer, Barbara M; van Alphen, Jacques J M; Kraaijeveld, Ken

2013-09-01

34

High Rates of Sexual Behavior in the General Population: Correlates and Predictors  

Microsoft Academic Search

We studied 2450, 18–60-year-old men and women from a 1996 national survey of sexuality and health in Sweden to identify risk\\u000a factors and correlates of elevated rates of sexual behavior (hypersexuality) in a representative, non-clinical population.\\u000a Interviews and questionnaires measured various sexual behaviors, developmental risk factors, behavioral problems, and health\\u000a indicators. The results suggested that correlates of high rates of

Niklas Långström; R. Karl Hanson

2006-01-01

35

Sex at the origin: an Asian population of the rice blast fungus Magnaporthe oryzae reproduces sexually.  

PubMed

Sexual reproduction may be cryptic or facultative in fungi and therefore difficult to detect. Magnaporthe oryzae, which causes blast, the most damaging fungal disease of rice, is thought to originate from southeast Asia. It reproduces asexually in all rice-growing regions. Sexual reproduction has been suspected in limited areas of southeast Asia, but has never been demonstrated in contemporary populations. We characterized several M. oryzae populations worldwide both biologically and genetically, to identify candidate populations for sexual reproduction. The sexual cycle of M. oryzae requires two strains of opposite mating types, at least one of which is female-fertile, to come into contact. In one Chinese population, the two mating types were found to be present at similar frequencies and almost all strains were female-fertile. Compatible strains from this population completed the sexual cycle in vitro and produced viable progenies. Genotypic richness and linkage disequilibrium data also supported the existence of sexual reproduction in this population. We resampled this population the following year, and the data obtained confirmed the presence of all the biological and genetic characteristics of sexual reproduction. In particular, a considerable genetic reshuffling of alleles was observed between the 2?years. Computer simulations confirmed that the observed genetic characteristics were unlikely to have arisen in the absence of recombination. We therefore concluded that a contemporary population of M. oryzae, pathogenic on rice, reproduces sexually in natura in southeast Asia. Our findings provide evidence for the loss of sexual reproduction by a fungal plant pathogen outside its centre of origin. PMID:22313491

Saleh, Dounia; Xu, Peng; Shen, Ying; Li, Chenguyn; Adreit, Henri; Milazzo, Joëlle; Ravigné, Virginie; Bazin, Eric; Nottéghem, Jean-Loup; Fournier, Elisabeth; Tharreau, Didier

2012-03-01

36

An Ephemeral Sexual Population of Phytophthora infestans in the Northeastern United States and Canada  

PubMed Central

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. PMID:25551215

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

37

Sexual size dimorphism in bighorn sheep ( Ovis canadensis ): effects of population density  

Microsoft Academic Search

Sexual dimorphism is an important characteristic of many mammals, but little is known about how environ- mental variables may affect its phenotypic expression. The relationships between population size, body mass, seasonal mass changes, and sexual mass dimorphism were investigated using 22 years of data on individually marked bighorn sheep (Ovis canadensis) on Ram Mountain, Alberta. The number of adult ewes

Mylène LeBlanc; Marco Festa-Bianchet; Jon T. Jorgenson

2001-01-01

38

Posttraumatic stress associated with delayed recall of sexual abuse: A general population study  

Microsoft Academic Search

This study examined delayed recall of childhood sexual abuse in a stratified random sample of the general population (N=505). Of participants who reported a history of sexual abuse, 42% described some period of time when they had less memory of the abuse than they did at the time of data collection. No demographic differences were found between subjects with continuous

Diana M. Elliott; John Briere

1995-01-01

39

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

ERIC Educational Resources Information Center

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%…

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

2009-01-01

40

Coalescence and genetic diversity in sexual populations under selection  

PubMed Central

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. PMID:24019480

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

2013-01-01

41

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

PubMed Central

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

Arnqvist, Göran; Tuda, Midori

2010-01-01

42

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

PubMed Central

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 in foraging behaviour, as well as differential threat-risk to external impacts such as fisheries bycatch. PMID:23028978

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

2012-01-01

43

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

PubMed Central

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

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

2013-01-01

44

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

PubMed

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. PMID:24174289

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

2014-02-01

45

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

PubMed Central

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

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

2011-01-01

46

Pattern of sexually transmitted diseases in a Malagasy population.  

PubMed

Between November 1992 and April 1993, interviews were conducted with 400 patients (169 men, 231 women) aged 14-52 years at the sexually transmitted disease (STD) clinic of the Institut d'Hygiene Sociale in Antananarivo, Madagascar, to determine the pattern of STDs and to improve treatment of the leading STDs. The 400 patients presented with 434 syndromes. 124 men had urethral discharge. 210 women had cervicovaginal discharge. 43 men and 18 women had genital ulcers. Clinicians could not establish a diagnosis in 33 patients. 171 patients had more than one infection. Chlamydia infection was the most common infection associated with another STD (gonorrhea in 22% of men and 11% of women with discharge, trichomoniasis in 2.4% of men and 13% of women, candidiasis in 1.6% of men and 9% of women, and bacterial vaginosis in 15% of women with discharge). Gonorrhea was the most common etiology for male discharge (69%) while chlamydia infection was for female discharge (52%). Women with discharge were more likely than men with discharge to have chlamydia infection (52% vs. 42%), trichomoniasis (30% vs. 9%; p 0.00001), and candidiasis (32% vs. 12%; p 0.00001). 37% of women with discharge had bacterial vaginosis. Chlamydia infection was the most common STD in this population (45%). 32% of male and 71% of female gonorrhea cases also had chlamydia infection. 70 patients had syphilis. 36 of them had secondary stage syphilis. No one had HIV-1 or HIV-2 infection. The most efficacious antibiotics for gonorrhea were ampicillin, ciprofloxacin, and spectinomycin (100% susceptibility). 31% and 26% of isolates were susceptible to tetracycline and cotrimoxazole, respectively. Public facilities in Madagascar do not have the capabilities to diagnosis chlamydia, resulting in many untreated chlamydia cases. These findings stress the need to improve combined treatment of gonorrhea and chlamydia infection and for educational efforts to increase awareness of genital ulcer disease. PMID:7871444

Harms, G; Matull, R; Randrianasolo, D; Andriamiadana, J; Rasamindrakotroka, A; Kirsch, T; Hof, U; Rarivoharilala, E; Korte, R

1994-01-01

47

Characteristics of victims of sexual abuse by gender and race in a community corrections population.  

PubMed

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 women, African American men, and African American women) using univariate and logistic regression analyses, which were conducted separately for each group. White women were the most likely to report a history of sexual abuse (26.5%), followed by African American women (16.0%), White men (4.0%), and African American men (1.1%). For all groups, histories of suicidal ideation and suicide attempts were associated with a history of sexual abuse. Sexual abuse was associated with substance abuse problems for women but not the men. Cannabis dependence was associated with sexual abuse for the White women while cocaine dependence was associated with sexual abuse for the African American women. Several other variables were associated with sexual abuse for women but not men, including lower education (White women only), a history of violent offenses (White women only), and living in a shelter (African American women only). African American men tended to have higher levels of education; this was the only variable uniquely associated with either male group. Receiving psychiatric medications was associated with sexual abuse for all groups except African American men and a history of sex for drugs was associated with sexual abuse for all groups except White men. Consistent with national sample, women, particularly White women, were more likely to be victims of sexual abuse. The gender-race differences for the sociodemographic factors associated with sexual abuse, particularly the risk of substance abuse for women, suggest the need for tailored interventions for sexual abuse prevention and treatment. PMID:22203627

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

2012-06-01

48

Population generation for large-scale simulation  

NASA Astrophysics Data System (ADS)

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 difficult. Investigators using the Hats Simulator must be able to control population parameters, and population generation must be fast enough to support studies that vary these parameters. This paper reports our experiences developing algorithms to generate populations whose structure is dependent on experimenter controlled parameters. In the next section, we outline the general problem of population generation and the details of building populations for the Hats Simulator. This is followed by a brief description of our initial, brute force algorithm (section 3). It was sufficient for small populations, but scaled horribly. We realized that the Law of Large Numbers would allow randomized methods to generate large populations that satisfied our constraints within acceptable bounds (section 5). It was while developing this algorithm that we discovered the connection between our population generation problem and recent results from the theory of random bipartite graphs (section 4). Finally, section 6 examines the properties and performance of our randomized algorithm. Though we will describe our results in terms of the Hats Simulator, these methods apply to any modeling situation in which populations of agents share multiple, overlapping structures, each of which is independent from the others. Our hope is that our experience will benefit others facing the task of generating large populations that require similar overlapping group structure.

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

2005-05-01

49

Sexual Activity and Impairment in Women with Systemic Sclerosis Compared to Women from a General Population Sample  

PubMed Central

Objective Reports of low sexual activity rates and high impairment rates among women with chronic diseases have not included comparisons to general population data. The objective of this study was to compare sexual activity and impairment rates of women with systemic sclerosis (SSc) to general population data and to identify domains of sexual function driving impairment in SSc. Methods Canadian women with SSc were compared to women from a UK population sample. Sexual activity and, among sexually active women, sexual impairment were evaluated with a 9-item version of the Female Sexual Function Index (FSFI). Results Among women with SSc (mean age?=?57.0 years), 296 of 730 (41%) were sexually active, 181 (61%) of whom were sexually impaired, resulting in 115 of 730 (16%) who were sexually active without impairment. In the UK population sample (mean age?=?55.4 years), 956 of 1,498 women (64%) were sexually active, 420 (44%) of whom were impaired, with 536 of 1,498 (36%) sexually active without impairment. Adjusting for age and marital status, women with SSc were significantly less likely to be sexually active (OR?=?0.34, 95%CI?=?0.28–0.42) and, among sexually active women, significantly more likely to be sexually impaired (OR?=?1.88, 95%CI?=?1.42–2.49) than general population women. Controlling for total FSFI scores, women with SSc had significantly worse lubrication and pain scores than general population women. Conclusions Sexual functioning is a problem for many women with scleroderma and is associated with pain and poor lubrication. Evidence-based interventions to support sexual activity and function in women with SSc are needed. PMID:23251692

Levis, Brooke; Burri, Andrea; Hudson, Marie; Baron, Murray; Thombs, Brett D.

2012-01-01

50

Studying allozyme variation in sexual and apomictic Taraxacum and Pilosella (Asteraceae) populations  

Microsoft Academic Search

Allozyme spectra of peroxidase, esterase, superoxid dismutase, tyrosinase, alcohol dehydrogenase, lactate dehydrogenase, and acid phosphatase were examined in populations of sexual (Taraxacum serotinum and Pilosella echioides) and apomictic (T. officinale and P. officinarum) plant species. The heterozygosity in these populations (0.455–0.620) proved to be considerably higher than the average level characteristic of plant populations (0.058–0.185). The populations examined did not

A. S. Kashin; V. E. Anfalov; Yu. A. Demochko

2005-01-01

51

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

PubMed

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. PMID:22269363

Yela, Carlos

2012-02-01

52

Molecular hyperdiversity and evolution in very large populations  

PubMed Central

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

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

2014-01-01

53

Sexual size dimorphism in bighorn sheep (Ovis canadensis): effects of population density  

E-print Network

Sexual size dimorphism in bighorn sheep (Ovis canadensis): effects of population density Mylène Le dimorphism were investigated using 22 years of data on individually marked bighorn sheep (Ovis canadensis individuelle des Mouflons d'Amérique (Ovis canadensis) de la population de Ram Mountain, Alberta. Le nombre de

Festa-Bianchet, Marco

54

Pheromonally Mediated Sexual Isolation Among Denning Populations of Red-Sided Garter Snakes, Thamnophis sirtalis parietalis  

Microsoft Academic Search

Utilizing behavioral experiments and chemical analyses, we examined whether pheromonally mediated sexual isolation exists between denning populations of red-sided garter snakes (Thamnophis sirtalis parietalis) in Manitoba, Canada. Simultaneous choice tests conducted during the breeding season revealed that adult males from a hibernaculum in central Manitoba displayed a strong courtship preference for females from their own population over females from a

Michael P. LeMaster; Robert T. Mason

2003-01-01

55

Morphometric modelling of ageing in the human pubic symphysis: sexual dimorphism in an Australian population.  

PubMed

Despite the prominent use of the pubic symphysis for age estimation in forensic anthropology, little has been documented regarding the quantitative morphological and micro-architectural changes of this surface. Specifically, utilising post-mortem computed tomography data from a large, contemporary Australian adult population, this study aimed to evaluate sexual dimorphism in the morphology and bone composition of the symphyseal surface; and temporal characterisation of the pubic symphysis in individuals of advancing age. The sample consisted of multi-slice computed tomography (MSCT) scans of the pubic symphysis (slice thickness: 0.5mm, overlap: 0.1mm) of 200 individuals of Caucasian ancestry aged 15-70 years, obtained in 2011. Surface rendering reconstruction of the symphyseal surface was conducted in OsiriX(®) (v.4.1) and quantitative analyses in Rapidform XOS™ and Osteomeasure™. Morphometric variables including inter-pubic distance, surface area, circumference, maximum height and width of the symphyseal surface and micro-architectural assessment of cortical and trabecular bone compositions were quantified using novel automated engineering software capabilities. The major results of this study are correlated with the macroscopic ossification and degeneration pattern of the symphyseal surface, demonstrating significant age-related changes in the morphometric and bone tissue variables between 15 and 70 years. Regardless of sex, the overall dimensions of the symphyseal surface increased with age, coupled with a decrease in bone mass in the trabecular and cortical bone compartments. Significant differences between the ventral, dorsal and medial cortical surfaces were observed, which may be correlated to bone formation activity dependent on muscle activity and ligamentous attachments. Our study demonstrates significant sexual dimorphism at this site, with males exhibiting greater surface dimensions than females. These baseline results provide a detailed insight into the changes in the structure of the pubic symphysis with ageing and sexually dimorphic features associated with the cortical and trabecular bone profiles. PMID:24468016

Lottering, Nicolene; Reynolds, Mikaela S; MacGregor, Donna M; Meredith, Matthew; Gregory, Laura S

2014-03-01

56

The Importance of Sexual and Clonal Reproduction for Population Dynamics in the Understory Herb Calathea marantifolia (Marantaceae).  

E-print Network

??I addressed how light availability influences sexual and clonal offspring production, demographic performance and contribution to population dynamics by studying the Neotropical understory herb Calathea… (more)

Matlaga, David Packard

2008-01-01

57

Large optic disks in the Marshallese population.  

PubMed

On routine examination, asymptomatic patients from the Marshall Islands were noted to have large optic disks associated with high cup/disk ratios and normal intraocular pressure. We retrospectively analyzed color fundus photographs of 54 eyes and 22 eyes of 15 patients had optic disks greater than 2.10 mm, or megalopapilla. Of 36 patients with cup/disk ratios exceeding 0.6, 31 (86%) had visual acuities of better than or equal to 20/30. The optic nerve rim and disk areas varied directly as did disk and cup diameters. Three large disks with an 18-year photographic follow-up showed no change. Optic disk characteristics can vary widely among genetically isolated populations. PMID:2913808

Maisel, J M; Pearlstein, C S; Adams, W H; Heotis, P M

1989-02-15

58

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

Microsoft Academic Search

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

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

2006-01-01

59

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

PubMed

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. PMID:24908456

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

2014-05-01

60

Pheromonally mediated sexual isolation among denning populations of red-sided garter snakes, Thamnophis sirtalis parietalis.  

PubMed

Utilizing behavioral experiments and chemical analyses, we examined whether pheromonally mediated sexual isolation exists between denning populations of red-sided garter snakes (Thamtnophis sirtalis parietalis) in Manitoba, Canada. Simultaneous choice tests conducted during the breeding season revealed that adult males from a hibernaculum in central Manitoba displayed a strong courtship preference for females from their own population over females from a hibernaculum in western Manitoba, whereas males from the western Manitoba hibernaculum showed no such preference. In addition. trailing experiments testing the response of males from the two hibernacula to familiar and unfamiliar female trails showed similar results, demonstrating that the observed male preference is mediated through chemical cues. Subsequent chemical analysis of the female sexual attractiveness pheromone. a homologous series of long-chain saturated and (omega-9 cis-unsaturated methyl ketones responsible for eliciting male courtship behavior and trailing behavior in garter snakes, showed significant variation in the composition of the pheromone between the two populations. Specifically, the two populations varied in the relative concentrations of individual unsaturated methyl ketones expressed by females. These results suggest that sexual isolation exists to a degree among denning populations of red-sided garter snakes due to variation in the expression of the female sexual attractiveness pheromone. PMID:12775159

Lemaster, Michael P; Mason, Robert T

2003-04-01

61

Fertility and sexual structure in a polygamous willow population  

Microsoft Academic Search

This note reports on an extraordinary polygamous population of Salix acmophylla from Nahal Dishon, Israel. Remarkably, all individuals in this population are bisexuals, that is, they all contain typically\\u000a female catkins (with some or without any male florets), typically male catkins (with some or without any female florets) and\\u000a mixed catkins. The proportions of these three catkin types in populations

A. Rottenberg

2007-01-01

62

Multiple sexual signals and behavioral reproductive isolation in a diverging population.  

PubMed

Sexual trait divergence has been shown to play a role in the evolution of reproductive isolation. While variation in multiple sexual signals is common among closely related species, little is known about the role of these different axes of phenotype variation with respect to the evolution of behavioral reproductive isolation. Here we study a unique population of barn swallows (Hirundo rustica transitiva) that can be distinguished phenotypically from its neighboring populations only on the basis of two features of male plumage: exaggerated expression of both long tail streamers and dark ventral coloration. Using phenotype manipulation experiments, we conducted a paternity study to examine whether both traits are sexually selected. Our results show that an exaggerated form of the local male phenotype (with both tail elongation and color darkening) is favored by local females, whereas males whose phenotypes were manipulated to look like males of neighboring subspecies suffered paternity losses from their social mates. These results confirm the multiple signaling role of the unique tail and color combination in our diverging population and suggest a novel possibility according to which multiple sexual signals may also be used to discriminate among males from nearby populations when prezygotic reproductive isolation is adaptive. PMID:24021403

Vortman, Yoni; Lotem, Arnon; Dor, Roi; Lovette, Irby; Safran, Rebecca J

2013-10-01

63

Natural and sexual selection against immigrants maintains differentiation among micro-allopatric populations  

Microsoft Academic Search

Local adaptation to divergent environmental conditions can promote popu- lation genetic differentiation even in the absence of geographic barriers and hence lead to speciation. But what mechanisms contribute to reproductive isolation among diverging populations? We tested for natural and sexual selection against immigrants in a fish species inhabiting (and adapting to) nonsulphidic surface habitats, sulphidic surface habitats and a sulphidic

M. TOBLER; R. RIESCH; C. M. TOBLER; T. SCHULZ-MIRBACH

2009-01-01

64

Differential costs of sexual and vegetative reproduction in wild strawberry populations  

Microsoft Academic Search

The CO2 costs of producing sexual and vegetative reproductive propagules were calculated for two species of wild strawberry, Fragaria virginiana and F. vesca. Five populations on sites representing a gradient of successional regrowth near Ithaca, New York, USA, were studied for two or three years each. Field studies of phenology, biomass, demography, and environment and laboratory studies of CO2 exchange

Thomas W. Jurik

1985-01-01

65

Density-dependent sexual reproduction in natural populations of the rotifer asplanchna girodi  

Microsoft Academic Search

The monogonont rotifer Asplanchna girodi was continuously present in daily and bi-daily plankton samples of Golf Course Pond during the spring of 1977. Two cycles of sexual reproduction occurred during this period. By isolation and culture of females it was possible to determine the reproductive type of collected individuals. Data thus obtained suggest that environmental cues associated with population density

Charles E. King; Terry W. Snell

1980-01-01

66

Sexual minority population density and incidence of lung, colorectal and female breast cancer in California  

PubMed Central

Objective Risk factors for breast, colorectal, and lung cancer are known to be more common among lesbian, gay, and bisexual (LGB) individuals, suggesting they may be more likely to develop these cancers. Our objective was to determine differences in cancer incidence by sexual orientation, using sexual orientation data aggregated at the county level. Methods Data on cancer incidence were obtained from the California Cancer Registry and data on sexual orientation were obtained from the California Health Interview Survey, from which a measure of age-specific LGB population density by county was calculated. Using multivariable Poisson regression models, the association between the age–race-stratified incident rate of breast, lung and colorectal cancer in each county and LGB population density was examined, with race, age group and poverty as covariates. Results Among men, bisexual population density was associated with lower incidence of lung cancer and with higher incidence of colorectal cancer. Among women, lesbian population density was associated with lower incidence of lung and colorectal cancer and with higher incidence of breast cancer; bisexual population density was associated with higher incidence of lung and colorectal cancer and with lower incidence of breast cancer. Conclusions These study findings clearly document links between county-level LGB population density and cancer incidence, illuminating an important public health disparity. PMID:24670430

Boehmer, Ulrike; Miao, Xiaopeng; Maxwell, Nancy I; Ozonoff, Al

2014-01-01

67

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

PubMed

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

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

2012-01-01

68

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

PubMed Central

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

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

2014-01-01

69

Sensation Seeking and Impulsivity: Combined Associations with Risky Sexual Behavior in a Large Sample of Young Adults  

Microsoft Academic Search

Although prior studies have shown that sensation seeking and impulsive decision-making are related to sexual risk-taking, it is still unclear whether these personality traits operate independently or synergistically. The purpose of this study was to elucidate the joint contribution of these personality traits to HIV and sexually transmitted disease (STD) risk behaviors using data from a large sample of sexually

Richard Charnigo; Seth M. Noar; Christopher Garnett; Richard Crosby; Philip Palmgreen; Rick S. Zimmerman

2012-01-01

70

Do american States with more religious or conservative populations search more for sexual content on google?  

PubMed

In America, religiosity and conservatism are generally associated with opposition to non-traditional sexual behavior, but prominent political scandals and recent research suggest a paradoxical private attraction to sexual content on the political and religious right. We examined associations between state-level religiosity/conservatism and anonymized interest in searching for sexual content online using Google Trends (which calculates within-state search volumes for search terms). Across two separate years, and controlling for demographic variables, we observed moderate-to-large positive associations between: (1) greater proportions of state-level religiosity and general web searching for sexual content and (2) greater proportions of state-level conservatism and image-specific searching for sex. These findings were interpreted in terms of the paradoxical hypothesis that a greater preponderance of right-leaning ideologies is associated with greater preoccupation with sexual content in private internet activity. Alternative explanations (e.g., that opposition to non-traditional sex in right-leaning states leads liberals to rely on private internet sexual activity) are discussed, as are limitations to inference posed by aggregate data more generally. PMID:25277691

MacInnis, Cara C; Hodson, Gordon

2015-01-01

71

SexualPopulation Structure and Genetics of the Malaria Agent P. falciparum  

PubMed Central

The population genetics and structure of P. falciparum determine the rate at which malaria evolves in response to interventions such as drugs and vaccines. This has been the source of considerable recent controversy, but here we demonstrate the organism to be essentially sexual, in an area of moderately high transmission in the Lower Shire Valley, Malawi. Seven thousand mosquitoes were collected and dissected, and genetic data were obtained on 190 oocysts from 56 infected midguts. The oocysts were genotyped at three microsatellite loci and the MSP1 locus. Selfing rate was estimated as 50% and there was significant genotypic linkage disequilibrium (LD) in the pooled oocysts. A more appropriate analysis searching for genotypic LD in outcrossed oocysts and/or haplotypic LD in the selfed oocysts found no evidence for LD, indicating that the population was effectively sexual. Inbreeding estimates at MSP1 were higher than at the microsatellites, possibly indicative of immune action against MSP1, but the effect was confounded by the probable presence of null mutations. Mating appeared to occur at random in mosquitoes and evidence regarding whether malaria clones in the same host were related (presumably through simultaneous inoculation in the same mosquito bite) was ambiguous. This is the most detailed genetic analysis yet of P. falciparum sexual stages, and shows P. falciparum to be a sexual organism whose genomes are in linkage equilibrium, which acts to slow the emergence of drug resistance and vaccine insensitivity, extending the likely useful therapeutic lifespan of drugs and vaccines. PMID:17637829

Mzilahowa, Themba; McCall, Philip J.; Hastings, Ian M.

2007-01-01

72

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

NASA Astrophysics Data System (ADS)

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.

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

2013-01-01

73

Genetic diversity in sexual diploid and apomictic tetraploid populations of Paspalum notatum situated in sympatry or allopatry  

Microsoft Academic Search

Paspalum notatum is a subtropical grass widely distributed in the temperate areas of America. Diploids are sexual while polyploids give rise to clonal seeds through aposporous apomixis. RAPD markers were used to analyze the genetic structure of three natural populations: i) diploids reproducing sexually (R2X); ii) sympatric apomictic tetraploids collected in the vicinity of the diploids (R4X); iii) allopatric apomictic

L. D. Daurelio; F. Espinoza; C. L. Quarin; S. C. Pessino

2004-01-01

74

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

PubMed Central

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 approach to prevention, targeting groups with a high level of impulsivity or behavioral problems, may have limited effect on the prevalence of ISA victimization. Thus, from a public health perspective, it may be advisable to give priority to universal preventive measures to curb young girls’ risk of being sexually assaulted in a state of alcohol-induced incapacitation. PMID:24774966

2014-01-01

75

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

NASA Astrophysics Data System (ADS)

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 North American subspecies, H. r. erythrogaster. Contrary to expectations, males did not have stronger responses to faster trilling (high performance) simulated intruders. Instead, resident males had stronger responses to the high performance stimulus only when the intruder was also darker than the resident. Collectively, my dissertation offers novel insight into the evolutionary dynamics of complex sexual signaling at multiple spatial scales.

Wilkins, Matthew Reed

76

Rapid evolution of a sexually selected trait following population establishment in a novel habitat.  

PubMed

Colonization of novel environments creates new selection pressures. Sexually selected traits are affected by the physical and social environment and should be especially susceptible to change, but this has rarely been studied. In southern California, dark-eyed juncos, (Junco hyemalis) naturally breed in mixed-coniferous temperate forests, typically from 1500 m to 3000 m in elevation. In the early 1980s, a small population became established in a coastal habitat, the University of California, San Diego campus, which has a mild, Mediterranean climate. I show that a sexually and socially selected signaling trait--the amount of white in the tail--has declined by approximately 22% as compared to mountain juncos. I address three main factors that could explain the difference between mountain and coastal juncos: phenotypic plasticity, genetic drift, and selection. Results indicate that the first two can be ruled out as the sole cause of the plumage change, which implies that selection contributed to the genetic differentiation from the mountain population. The estimated rate of evolution is about 0.2 haldanes, comparable with rates of change in systems where individuals have been artificially introduced into new environments (e.g., guppies and Drosophila). This is the first study to demonstrate evolution of a sexually selected trait after only several generations resulting from a natural invasion into a novel environment. PMID:15058729

Yeh, Pamela J

2004-01-01

77

Assessing the association between childhood sexual abuse and adult sexual experiences in women with sexual difficulties.  

PubMed

Self-report instruments for assessing sexual well-being in women with sexual difficulties have not to date been explicitly validated among women with a history of childhood sexual abuse (CSA). Given an extensive literature suggesting psychological differences between women with and without a history of CSA, it is possible that sexual well-being has a different meaning for these groups. Without validated scales, it is difficult to evaluate the impact of early sexual trauma on adult sexuality. The present study assessed whether the factor structure of widely used measures of sexual well-being were consistent across women experiencing sexual difficulties, with and without an abuse history, and to estimate effect sizes for the statistical effect of CSA on sexual well-being in this population. A sample of women with and without a history of CSA (N = 238) completed the Female Sexual Function Index and the Sexual Satisfaction Scale for Women. Structural equation models indicated generally consistent factor structures across groups, suggesting good construct validity. Effect size estimates indicated medium to large (0.53-0.72) effects of CSA on sexual well-being for women with sexual difficulties. These findings support and extend research regarding the potential effects of CSA that may inform treatment for this population. PMID:24948536

Stephenson, Kyle R; Pulverman, Carey S; Meston, Cindy M

2014-06-01

78

Structural Stigma and All-Cause Mortality in Sexual Minority Populations  

PubMed Central

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

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

2013-01-01

79

High variation in clonal vs. sexual reproduction in populations of the wild strawberry, Fragaria virginiana (Rosaceae)  

PubMed Central

Background and Aims Many plants reproduce both clonally and sexually, and the balance between the two modes of reproduction will vary among populations. Clonal reproduction was characterized in three populations of the wild strawberry, Fragaria virginiana, to determine the extent that reproductive mode varied locally between sites. The study sites were fragmented woodlands in Cook County, Illinois, USA. Methods A total of 95 strawberry ramets were sampled from the three sites via transects. Ramets were mapped and genotyped at five variable microsatellite loci. The variability at these five loci was sufficient to assign plants to clones with high confidence, and the spatial pattern of genets was mapped at each site. Key Results A total of 27 distinct multilocus genotypes were identified. Of these, 18 genotypes were detected only once, with the remaining nine detected in multiple ramets. The largest clone was identified in 16 ramets. No genets were shared between sites, and each site exhibited markedly different clonal and sexual recruitment patterns, ranging from two non-overlapping and widespread genets to 19 distinct genets. Only one flowering genet was female; the remainder were hermaphrodites. Conclusions Local population history or fine-scale ecological differences can result in dramatically different reproductive patterns at small spatial scales. This finding may be fairly widespread among clonal plant species, and studies that aim to characterize reproductive modes in species capable of asexual reproduction need to evaluate reproductive modes in multiple populations and sites. PMID:19797422

Wilk, John A.; Kramer, Andrea T.; Ashley, Mary V.

2009-01-01

80

Using Cognitive Interviews to Evaluate Items for Measuring Sexual Functioning Across Cancer Populations: Improvements and Remaining Challenges  

PubMed Central

Purpose One goal of the Patient-Reported Outcomes Measurement Information System™ (PROMIS™) is to develop a measure of sexual functioning that broadens the definition of sexual activity and incorporates items that reflect constructs identified as important by patients with cancer. We describe how cognitive interviews improved the quality of the items and discuss remaining challenges to assessing sexual functioning in research with cancer populations. Methods We conducted 39 cognitive interviews of patients with cancer and survivors on the topic of sexual experience. Each of the 83 candidate items was seen by 5 to 24 participants. Participants included both men and women and varied by cancer type, treatment trajectory, race, and literacy level. Significantly revised items were retested in subsequent interviews. Results Cognitive interviews provided useful feedback about the relevance, sensitivity, appropriateness, and clarity of the items. Participants identified broad terms (eg, “sex life”) to assess sexual experience and exposed the challenges of measuring sexual functioning consistently, considering both adjusted and unadjusted sexual experiences. Conclusions Cognitive interviews were critical for item refinement in the development of the PROMIS measure of sexual function. Efforts are underway to validate the measure in larger cancer populations. PMID:19672697

Fortune-Greeley, Alice K.; Flynn, Kathryn E.; Jeffery, Diana D.; Williams, Megan S.; Keefe, Francis J.; Reeve, Bryce B.; Willis, Gordon B.; Weinfurt, Kevin P.

2009-01-01

81

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

PubMed Central

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 victim services and prevention strategies should be built on this knowledge. PMID:7553516

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

1995-01-01

82

Generalizing Classification Tables to Large Populations.  

ERIC Educational Resources Information Center

The technique of generalizing sample results in a classification study to large subpopulations of unequal sizes was examined. The usual output from the discriminant analysis routine in the Statistical Package for the Social Sciences was extended to handle the present statistical problems. Advantages of the technique were discussed. (Author/DWH)

Koslowsky, Meni

1985-01-01

83

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

PubMed Central

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

Yingying, Huang; Smith, Kumi; Suiming, Pan

2011-01-01

84

Significance of temporal changes on sexual dimorphism of cranial measurements of Indian population.  

PubMed

Revision of discriminant function formulae has always been advocated by anthropologist to take into account the changing pattern of sexual dimorphism due to temporal/secular changes. The present study aims to track temporal changes in cranial measurements of temporally distinct North Indian population and providing updated sex discriminating formulae. A total of 483 adult (20-65 years) crania representing contemporary and sub-recent populations collected from two medical colleges in North India. A total of 11 variables were measured to observe the changes in cranial dimension over time. Analysis of data demonstrated significant sexual and population (contemporary vs sub-recent sample) variations over time. The contemporary males and females exhibited larger cranial dimensions but it expressed less dimorphism than their predecessors. A trend toward brachycephalization was also observed in contemporary females. Maximum cranial length (84%) and biauricular breadth (79%) represent the most dimorphic variables for contemporary and sub-recent sample, respectively. The possible causes of such variations are discussed. PMID:25043554

Saini, Vineeta

2014-09-01

85

Differences in Chemical Sexual Signals May Promote Reproductive Isolation and Cryptic Speciation between Iberian Wall Lizard Populations  

PubMed Central

Interpopulational variation in sexual signals may lead to premating reproductive isolation and speciation. Genetic and morphological studies suggest that the Iberian wall lizard, Podarcis hispanica, forms part of a “species complex” with several cryptic species. We explored the role of chemical sexual signals in interpopulational recognition between five distinct populations of Iberian wall lizards in Central Spain. Results showed that these populations differed in morphology and in composition and proportion of chemical compounds in femoral gland secretions of males. Tongue-flick experiments indicated that male and female lizards discriminated and were more interested in scents of lizards from their own area (i.e., Northern versus Southern populations), but did not discriminate between all populations. Moreover, only males from the populations that are geographically located more far away preferred scent of females from their own population. These data suggest that, at least between some populations, there may be reproductive isolation mediated by chemical signals and cryptic speciation. PMID:22288019

Gabirot, Marianne; López, Pilar; Martín, José

2012-01-01

86

Intragenomic conflict in populations infected by Parthenogenesis Inducing Wolbachia ends with irreversible loss of sexual reproduction  

PubMed Central

Background The maternally inherited, bacterial symbiont, parthenogenesis inducing (PI) Wolbachia, causes females in some haplodiploid insects to produce daughters from both fertilized and unfertilized eggs. The symbionts, with their maternal inheritance, benefit from inducing the production of exclusively daughters, however the optimal sex ratio for the nuclear genome is more male-biased. Here we examine through models how an infection with PI-Wolbachia in a previously uninfected population leads to a genomic conflict between PI-Wolbachia and the nuclear genome. In most natural populations infected with PI-Wolbachia the infection has gone to fixation and sexual reproduction is impossible, specifically because the females have lost their ability to fertilize eggs, even when mated with functional males. Results The PI Wolbachia infection by itself does not interfere with the fertilization process in infected eggs, fertilized infected eggs develop into biparental infected females. Because of the increasingly female-biased sex ratio in the population during a spreading PI-Wolbachia infection, sex allocation alleles in the host that cause the production of more sons are rapidly selected. In haplodiploid species a reduced fertilization rate leads to the production of more sons. Selection for the reduced fertilization rate leads to a spread of these alleles through both the infected and uninfected population, eventually resulting in the population becoming fixed for both the PI-Wolbachia infection and the reduced fertilization rate. Fertilization rate alleles that completely interfere with fertilization ("virginity alleles") will be selected over alleles that still allow for some fertilization. This drives the final resolution of the conflict: the irreversible loss of sexual reproduction and the complete dependence of the host on its symbiont. Conclusions This study shows that dependence among organisms can evolve rapidly due to the resolution of the conflicts between cytoplasmic and nuclear genes, and without requiring a mutualism between the partners. PMID:20667099

2010-01-01

87

Urologic Characteristics and Sexual Behaviors Associated with Prostate Cancer in an African-Caribbean Population in Barbados, West Indies  

PubMed Central

Prostate cancer (PC) is the principal malignancy affecting African descent men in the Caribbean and the USA. Disparities in incidence, prevalence, and mortality in these populations are poorly understood. We evaluated the urologic characteristics and sexual behaviors of men with histologically confirmed PC (cases) and age-matched controls in the nationwide Prostate Cancer in a Black Population (PCBP) study conducted in Barbados. Cases were around 1.5 to 3 times more likely to report symptoms of prostatic enlargement, hematuria/hematospermia, and previous prostatitis. Sexually transmitted infections (STIs) were similar among cases (24.5%) and controls (26.7%). First sexual intercourse before the age of 16 was associated with an increased likelihood of both low- (Gleason score < 7; OR 1.63; 95% CI: 1.03–1.66) and high-grade PC (Gleason score ? 7; OR 1.82; 1.11–2.99). PC risk decreased with later age of sexual debut (P-trend = 0.004). More lifetime sexual partners was associated with increased odds of high grade PC (P-trend = 0.02). The contribution of sexual behaviors to the development and the outcomes of PC is likely due to multiple mechanisms, and further study will be necessary to elucidate the underlying pathophysiologic mechanisms in this and similar populations. PMID:23533778

Hennis, Anselm J. M.; Wu, Suh-Yuh; Nemesure, Barbara; Leske, M. Cristina

2013-01-01

88

Urologic characteristics and sexual behaviors associated with prostate cancer in an african-Caribbean population in barbados, west indies.  

PubMed

Prostate cancer (PC) is the principal malignancy affecting African descent men in the Caribbean and the USA. Disparities in incidence, prevalence, and mortality in these populations are poorly understood. We evaluated the urologic characteristics and sexual behaviors of men with histologically confirmed PC (cases) and age-matched controls in the nationwide Prostate Cancer in a Black Population (PCBP) study conducted in Barbados. Cases were around 1.5 to 3 times more likely to report symptoms of prostatic enlargement, hematuria/hematospermia, and previous prostatitis. Sexually transmitted infections (STIs) were similar among cases (24.5%) and controls (26.7%). First sexual intercourse before the age of 16 was associated with an increased likelihood of both low- (Gleason score < 7; OR 1.63; 95% CI: 1.03-1.66) and high-grade PC (Gleason score ? 7; OR 1.82; 1.11-2.99). PC risk decreased with later age of sexual debut (P-trend = 0.004). More lifetime sexual partners was associated with increased odds of high grade PC (P-trend = 0.02). The contribution of sexual behaviors to the development and the outcomes of PC is likely due to multiple mechanisms, and further study will be necessary to elucidate the underlying pathophysiologic mechanisms in this and similar populations. PMID:23533778

Hennis, Anselm J M; Wu, Suh-Yuh; Nemesure, Barbara; Leske, M Cristina

2013-01-01

89

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

PubMed

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. PMID:24170186

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

90

Enriching Ploidy Level Diversity: the Role of Apomictic and Sexual Biotypes of Hieracium subgen. Pilosella (Asteraceae) that Coexist in Polyploid Populations  

Microsoft Academic Search

The capacity to generate variation in ploidy and reproductive mode was compared in facultatively apomictic versus sexual maternal\\u000a plants that coexist in two model populations. The population structure was studied in polyploid hybrid swarms comprised of\\u000a Hieracium pilosella (usually sexual, less commonly apomictic), H. bauhini (apomictic), and their hybrids (sexual, apomictic, or sterile). Relationships among established biotypes were proposed on

Anna Krahulcová; Olga Rotreklová; František Krahulec; Radka Rosenbaumová; Ivana Pla?ková

2009-01-01

91

Trends in sexually transmitted infections in general practice 1990-2000: population based study using data from the UK general practice research database  

PubMed Central

Objective To describe the contribution of primary care to the diagnosis and management of sexually transmitted infections in the United Kingdom, 1990-2000, in the context of increasing incidence of infections in genitourinary medicine clinics. Design Population based study. Setting UK primary care. Participants Patients registered in the UK general practice research database. Main outcome measures Incidence of diagnosed sexually transmitted infections in primary care and estimation of the proportion of major such infections diagnosed in primary care. Results An estimated 23.0% of chlamydia cases in women but only 5.3% in men were diagnosed and treated in primary care during 1998-2000, along with 49.2% cases of non-specific urethritis and urethral discharge in men and 5.7% cases of gonorrhoea in women and 2.9% in men. Rates of diagnosis in primary care rose substantially in the late 1990s. Conclusions A substantial and increasing number of sexually transmitted infections are diagnosed and treated in primary care in the United Kingdom, with sex ratios differing from those in genitourinary medicine clinics. Large numbers of men are treated in primary care for presumptive sexually transmitted infections. PMID:16439371

Cassell, Jackie A; Mercer, Catherine H; Sutcliffe, Lorna; Petersen, Irene; Islam, Amir; Brook, M Gary; Ross, Jonathan D; Kinghorn, George R; Simms, Ian; Hughes, Gwenda; Majeed, Azeem; Stephenson, Judith M; Johnson, Anne M; Hayward, Andrew C

2006-01-01

92

Sexual and postmating reproductive isolation between allopatric Drosophila montana populations suggest speciation potential  

PubMed Central

Background Widely distributed species with populations adapted to different environmental conditions can provide valuable opportunities for tracing the onset of reproductive incompatibilities and their role in the speciation process. Drosophila montana, a D. virilis group species found in high latitude boreal forests in Nearctic and Palearctic regions around the globe, could be an excellent model system for studying the early stages of speciation, as a wealth of information concerning this species' ecology, mating system, life history, genetics and phylogeography is available. However, reproductive barriers between populations have hereto not been investigated. Results We report both pre- and postmating barriers to reproduction between flies from European (Finnish) and North American (Canadian) populations of Drosophila montana. Using a series of mate-choice designs, we show that flies from these two populations mate assortatively (i.e., exhibit significant sexual isolation) while emphasizing the importance of experimental design in these kinds of studies. We also assessed potential postmating isolation by quantifying egg and progeny production in intra- and interpopulation crosses and show a significant one-way reduction in progeny production, affecting both male and female offspring equally. Conclusion We provide evidence that allopatric D. montana populations exhibit reproductive isolation and we discuss the potential mechanisms involved. Our data emphasize the importance of experimental design in studies on premating isolation between recently diverged taxa and suggest that postmating barriers may be due to postcopulatory-prezygotic mechanisms. D. montana populations seem to be evolving multiple barriers to gene flow in allopatry and our study lays the groundwork for future investigations of the genetic and phenotypic mechanisms underlying these barriers. PMID:21396136

2011-01-01

93

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

PubMed Central

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

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

2014-01-01

94

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

PubMed

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

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

2014-11-01

95

Large-scale spatial population databases in infectious disease research  

PubMed Central

Modelling studies on the spatial distribution and spread of infectious diseases are becoming increasingly detailed and sophisticated, with global risk mapping and epidemic modelling studies now popular. Yet, in deriving populations at risk of disease estimates, these spatial models must rely on existing global and regional datasets on population distribution, which are often based on outdated and coarse resolution data. Moreover, a variety of different methods have been used to model population distribution at large spatial scales. In this review we describe the main global gridded population datasets that are freely available for health researchers and compare their construction methods, and highlight the uncertainties inherent in these population datasets. We review their application in past studies on disease risk and dynamics, and discuss how the choice of dataset can affect results. Moreover, we highlight how the lack of contemporary, detailed and reliable data on human population distribution in low income countries is proving a barrier to obtaining accurate large-scale estimates of population at risk and constructing reliable models of disease spread, and suggest research directions required to further reduce these barriers. PMID:22433126

2012-01-01

96

Inclusive fitness and sexual conflict: How population structure can modulate the battle of the sexes.  

PubMed

Competition over reproductive opportunities among members of one sex often harms the opposite sex, creating a conflict of interest between individual males and females. Recently, this battle of the sexes has become a paradigm in the study of intersexual coevolution. Here, we review recent theoretical and empirical advances suggesting that - as in any scenario of intraspecific competition - selfishness (competitiveness) can be influenced by the genetic relatedness of competitors. When competitors are positively related (e.g. siblings), an individual may refrain from harming its competitor(s) and their mate(s) because this can improve the focal individual's inclusive fitness. These findings reveal that population genetic structure might be of paramount importance when studying the battle of the sexes. We conclude by identifying some new lines of research at the interface of sexual selection and social evolution. PMID:25389109

Pizzari, Tommaso; Biernaskie, Jay M; Carazo, Pau

2015-02-01

97

Modeling mid-aged women's sexual functioning: a prospective, population-based study.  

PubMed

This article uses a prospectively, annually collected sexuality questionnaire from an 8-year study of 340 mid-aged Melbourne women. We modeled the interactions of sexuality domains, the effect of prior level of sexual functioning, and the effects of change in partner-related factors. We found that we were unable to separate items denoting sexual interest from those denoting responsiveness. Using the statistical technique of auto-correlation, we determined that the most important predictor of female sexual functioning is prior level of sexual functioning. Partner-related factors (change in partner status and feelings for partner) also had significant effects. PMID:15205073

Dennerstein, Lorraine; Lehert, Philippe

2004-01-01

98

Adaptive divergence and speciation among sexual and pseudoviviparous populations of Festuca  

PubMed Central

Pseudovivipary is an environmentally induced flowering abnormality in which vegetative shoots replace seminiferous (sexual) inflorescences. Pseudovivipary is usually retained in transplantation experiments, indicating that the trait is not solely induced by the growing environment. Pseudovivipary is the defining characteristic of Festuca vivipara, and arguably the only feature separating this species from its closest seminiferous relative, Festuca ovina. We performed phylogenetic and population genetic analysis on sympatric F. ovina and F. vivipara samples to establish whether pseudovivipary is an adaptive trait that accurately defines the separation of genetically distinct Festuca species. Chloroplast and nuclear marker-based analyses revealed that variation at a geographical level can exceed that between F. vivipara and F. ovina. We deduced that F. vivipara is a recent species that frequently arises independently within F. ovina populations and has not accumulated significant genetic differentiation from its progenitor. We inferred local gene flow between the species. We identified one amplified fragment length polymorphism marker that may be linked to a pseudovivipary-related region of the genome, and several other markers provide evidence of regional local adaptation in Festuca populations. We conclude that F. vivipara can only be appropriately recognized as a morphologically and ecologically distinct species; it lacks genetic differentiation from its relatives. This is the first report of a ‘failure in normal flowering development' that repeatedly appears to be adaptive, such that the trait responsible for species recognition constantly reappears on a local basis. PMID:20959864

Chiurugwi, T; Beaumont, M A; Wilkinson, M J; Battey, N H

2011-01-01

99

Association of sexual problems with social, psychological, and physical problems in men and women: a cross sectional population survey  

Microsoft Academic Search

STUDY OBJECTIVE: To investigate the association of sexual problems with social, physical, and psychological problems. DESIGN: An anonymous postal questionnaire survey. SETTING: Four general practices in England. PARTICIPANTS: 789 men and 979 women responding to a questionnaire sent to a stratified random sample of the adult general population (n = 4000). MAIN RESULTS: Strong physical, social, and psychological associations were

K. M. Dunn; P. R. Croft; G. I. Hackett

1999-01-01

100

Among-population variation in adipose fin size parallels the expression of other secondary sexual characteristics in  

E-print Network

secondary sexual characteristics in sockeye salmon (Oncorhynchus nerka) Peter A. H. Westley Ã? Stephanie M size of mature male sockeye salmon, Oncorhynchus nerka, among five popu- lations. Populations differed. Reimchen and Temple (2004) experimentally removed adipose fins from juvenile steelhead trout, Oncorhynchus

Carlson, Stephanie

101

Sexually dimorphic distribution of substance P in specific anterior pituitary cell populations.  

PubMed Central

Substance P (SP) immunoreactivity is detectable in the rat pituitary by RIA; however, immunolocalization has been difficult. We used a sensitive immunogold silver-enhancement staining technique to cytochemically locate SP in the gland. SP-immunoreactive (SP-ir) cells were seen in anterior pituitary (AP), and occasional SP-ir fibers and terminals were seen in both AP and posterior pituitary. Colocalization studies showed the vast majority of SP-ir cells in the male AP to be also immunoreactive for growth hormone (GH). These GH/SP-ir cells represent approximately 23% of the somatotroph population in the male. SP-ir cells did not colocalize with lactotrophs, gonadotrophs, or corticotrophs; however, rare thyroid-stimulating hormone/SP-ir cells were found in the male AP. Comparisons of pituitaries from males and females revealed that females have 70% fewer SP-ir cells and that only approximately 6% of the somatotrophs in the female express SP. This sexual dimorphism is diminished in 6-day ovariectomized rats because this treatment increases the GH/SP-ir cell population 3-fold. This result suggests that the previously reported estrogen-induced decrease in SP gene and peptide expression in the pituitary occurs, at least in part, in a subpopulation of somatotrophs. To test this hypothesis, distribution of SP-ir cells was examined in pituitaries from estrogen- and oil-treated ovariectomized rats. Estrogen reduced the percentage of somatotrophs with SP immunoreactivity by 70% compared with ovariectomized oil-treated controls, indicating that estrogen most likely regulates SP levels in the pituitary by acting on a subpopulation of somatotrophs to suppress SP expression. Estrogen does not appear to alter SP immunoreactivity that is detected in the additional population of SP cells that colocalize with thyroid-stimulating hormone. These SP-expressing thyrotrophs were seen 6-fold more frequently in the female than in the male pituitary, regardless of steroid status. These studies reveal that males have more total SP-ir cells in the AP than do females and that there is a sexually dimorphic pattern of SP distribution in the gland. Males have a higher percentage of SP-ir GH cells, whereas females have more SP-ir thyrotrophs than do males. Identification of independently regulated SP-ir somatotroph and thyrotroph populations provides a basis for investigating the roles of SP in autocrine or paracrine regulation of pituitary hormone secretion. Images PMID:1705031

Brown, E R; Roth, K A; Krause, J E

1991-01-01

102

The Power to Detect Quantitative Trait Loci Using Resequenced, Experimentally Evolved Populations of Diploid, Sexual Organisms  

PubMed Central

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. PMID:24441104

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

2014-01-01

103

Pricing under information asymmetry for a large population of users  

Microsoft Academic Search

In this paper, we study optimal nonlinear pricing policy de- sign for a monopolistic network service provider in the face of a large population of users. We assume that users have stochastic types. In (1), games with information symmetry have been considered; that is, users' true types may be pub- lic information available to all parties, or each user's true

Hongxia Shen; Tamer Basar

2007-01-01

104

Dynamical Quorum Sensing and Synchronization in Large Populations  

E-print Network

Dynamical Quorum Sensing and Synchronization in Large Populations of Chemical Oscillators Annette F oscillate in nearly complete synchrony (12). This type of transition is much like quorum-sensing transitions solution (15). Many examples of quorum- sensing transitions have been found, such as the appearance

Showalter, Kenneth

105

JELLYFISH BLOOMS Increasing jellyfish populations: trends in Large Marine  

E-print Network

JELLYFISH BLOOMS Increasing jellyfish populations: trends in Large Marine Ecosystems Lucas Brotz there are various indications and claims that jellyfish (i.e., scyphozoans, cubozoans, most hydrozoans, ctenophores never been pre- sented. Because this is mainly due to scarcity of quantitative time series of jellyfish

Pauly, Daniel

106

Enzyme variability in large-lake Daphnia populations  

Microsoft Academic Search

Allozyme studies of two primarily parthenogenetic, large-lake Daphnia species, D. galeata mendotae and D. cucullata, revealed high clonal diversity and levels of enzyme polymorphism similar to those found in other groups of organisms. Temporal analyses showed moderate stability of genotypes. Hardy–Weinberg deviations were detected on some dates in D. cucullata, most often resulting from homozygote excesses. Thus, these populations show

Mona A Mort; Hans Georg Wolf

1985-01-01

107

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

PubMed

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. PMID:25200798

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

2014-12-01

108

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

PubMed

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

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

2011-07-26

109

Treatment-seeking behavior for sexually transmitted infections in a high-risk population.  

PubMed

The World Health Organization estimates that 340 million new cases of curable sexually transmitted infections (STIs) occur every year, while 33 million individuals are estimated to be living with HIV. The AIDS and STI epidemics are not independent with untreated STIs increasing HIV acquisition and transmission. Female sex workers have increased prevalence of untreated STIs and have been hypothesized to affect the health and HIV incidence of the general population. This paper aims to investigate why some female sex workers who experience symptoms of vaginal discharge or genital ulcers seek treatment while others do not. Data were collected from a cohort study conducted between 2002 and 2005 among female bar and hotel workers in Moshi, Tanzania. Study subjects were recruited from 7 out of 15 administrative wards in Moshi as part of the Moshi's Women's Health Project. Data were restricted to women self-reporting symptoms of vaginal discharge or genital ulcers (n=459) within the past year. Logistic regression was performed with SAS 9.1. Qualitative analysis was performed using in-depth interviews and focus group discussions among a convenience sample (n=42) of women already enrolled in the study. All interviews and focus group discussions were tape-recorded and transcribed, and data were analyzed thematically. Sixty-four percent of the sample sought treatment for either ailment. Multivariate analysis identified relationship to man of last sexual intercourse, ever experiencing a pregnancy, and age as significant predictors to seeking treatment. Four salient themes of threats to fertility, stigma correlated with prostitution, discomfort with the physical exam, and perceived views of clients were revealed as predictors to why women seek or intentionally ignore symptoms. Understanding the motivations and barriers for seeking treatment of STIs has far ranging public health implications that could help curtail the unnecessary associated morbidity and mortality and curtail the transmission of HIV. PMID:20635239

Rosenheck, Rachel; Ngilangwa, David; Manongi, Rachael; Kapiga, Saidi

2010-11-01

110

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

PubMed

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. PMID:24364817

Peixoto, Maria Manuela; Nobre, Pedro

2015-01-01

111

Preferential sexual transmission of pseudorabies virus in feral swine populations may not account for observed seroprevalence in the USA  

PubMed Central

This paper compares the behavior of two competing models for the transmission of pseudorabies virus in feral swine in the USA. In first model, horizontal (non-sexual) density dependent transmission is the only transmission modality. In the second model, the only transmission modality is sexual transmission between mature males and females. The comparison of model behavior was carried out to test the hypothesis that preferential sexual transmission of PRV in feral swine can account for the seroprevalence observed in the field. The observed range of seroprevalence of PRV in mature feral swine in the USA is consistent with a preferential sexual transmission only if the feral swine mating system is a random mating system or a polygynous system in which there is a relatively large rate of acquisition of new mates. The observed range of seroprevalence of PRV in mature feral swine in the USA is not consistent with a preferential sexual transmission if there is mate guarding. This is important because the National Pseudorabies Surveillance Plan deems monitoring the risk of PRV introduction from feral swine to be a “minor objective” both in terms of the scope of the plan and with respect to the resources allocated. The rationale for this statement was derived from experimental studies, which suggested that the PRV indigenous to feral swine in the USA is preferentially sexually transmitted. PMID:21962753

Smith, Gary

2013-01-01

112

Large-scale identification of proteins involved in the development of a sexually dimorphic behavior.  

PubMed

Sexually dimorphic behaviors develop under the influence of sex steroids, which induce reversible changes in the underlying neural network of the brain. However, little is known about the proteins that mediate these activational effects of sex steroids. Here, we used a proteomics approach for large-scale identification of proteins involved in the development of a sexually dimorphic behavior, the electric organ discharge of brown ghost knifefish, Apteronotus leptorhynchus. In this weakly electric fish, the discharge frequency is controlled by the medullary pacemaker nucleus and is higher in males than in females. After lowering the discharge frequency by chronic administration of ?-estradiol, 2-dimensional difference gel electrophoresis revealed 62 proteins spots in tissue samples from the pacemaker nucleus that exhibited significant changes in abundance of >1.5-fold. The 20 identified protein spots indicated, among others, a potential involvement of astrocytes in the establishment of the behavioral dimorphism. Indeed, immunohistochemical analysis demonstrated higher expression of the astrocytic marker protein GFAP and increased gap-junction coupling between astrocytes in females compared with males. We hypothesize that changes in the size of the glial syncytium, glial coupling, and/or number of glia-specific potassium channels lead to alterations in the firing frequency of the pacemaker nucleus via a mechanism mediating the uptake of extracellular potassium ions from the extracellular space. PMID:24478160

Zupanc, Günther K H; Ilies, Iulian; Sîrbulescu, Ruxandra F; Zupanc, Marianne M

2014-04-01

113

Multi-level sexual selection: Individual and family-level selection for mating success in a historical human population  

PubMed Central

Precopulatory sexual selection is the association between fitness and traits associated with mate acquisition. While sexual selection is generally recognized to be a powerful evolutionary force, most investigations are limited to characters belonging to individuals. A broader multi-level perspective acknowledges that individual fitness can be affected by aspects of mating success that are characters of groups, such as families. Parental mating success in polygynous or polyandrous human societies may exemplify traits under group-level sexual selection. Using fitness measures that account for age-structure, I measure multi-level selection for mate number over 55 years in a human population with declining rates of polygyny. Sexual selection had three components: individual-level selection for ever-mating (whether or not an individual mated) and individual- and family-level selection for polyandry and polygyny. Family- and individual-level selection for polygyny was equally strong, three times stronger than family-level selection for polyandry and more than an order of magnitude stronger than individual-level selection for polyandry. However, individual-level selection for polyandry and polygyny was more effective at explaining relative fitness variance than family-level selection. Selection for ever-mating was the most important source of sexual selection for fitness; variation for ever-mating explained 23% of relative fitness variance. PMID:23730758

Moorad, Jacob

2013-01-01

114

U.S. population estimates and correlates of sexual abuse of community-dwelling older adults.  

PubMed

We describe the annual prevalence of sexual abuse among community-dwelling older adults in the United States. We also describe factors associated with experiencing sexual abuse. We used data from 24,343 older adults from the 2005 Behavioral Risk Factor Surveillance System pooled across 18 states. We estimated prevalence of sexual abuse, bivariate distributions, and odds ratio associations across demographic, health, and contextual factors. Our results show that 0.9% of older adults reported experiencing sexual abuse in the previous year. This represents approximately 90,289 community-dwelling older adults. We also report on factors associated with experiencing recent sexual abuse. There was a significant gender by binge drinking interaction, with a stronger association among women. There is a need for health promotion efforts targeted specifically toward older adults, encouraging them to seek services, if possible, after exposure to sexual abuse. PMID:24410194

Cannell, Michael B; Manini, Todd; Spence-Almaguer, Emily; Maldonado-Molina, Mildred; Andresen, Elena M

2014-01-01

115

Twenty years after international conference on population and development: where are we with adolescent sexual and reproductive health and rights?  

PubMed

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. PMID:25528975

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

2015-01-01

116

Poppr: an R package for genetic analysis of populations with clonal, partially clonal, and/or sexual reproduction  

PubMed Central

Many microbial, fungal, or oomcyete populations violate assumptions for population genetic analysis because these populations are clonal, admixed, partially clonal, and/or sexual. Furthermore, few tools exist that are specifically designed for analyzing data from clonal populations, making analysis difficult and haphazard. We developed the R package poppr providing unique tools for analysis of data from admixed, clonal, mixed, and/or sexual populations. Currently, poppr can be used for dominant/codominant and haploid/diploid genetic data. Data can be imported from several formats including GenAlEx formatted text files and can be analyzed on a user-defined hierarchy that includes unlimited levels of subpopulation structure and clone censoring. New functions include calculation of Bruvo’s distance for microsatellites, batch-analysis of the index of association with several indices of genotypic diversity, and graphing including dendrograms with bootstrap support and minimum spanning networks. While functions for genotypic diversity and clone censoring are specific for clonal populations, several functions found in poppr are also valuable to analysis of any populations. A manual with documentation and examples is provided. Poppr is open source and major releases are available on CRAN: http://cran.r-project.org/package=poppr. More supporting documentation and tutorials can be found under ‘resources’ at: http://grunwaldlab.cgrb.oregonstate.edu/. PMID:24688859

Tabima, Javier F.; Grünwald, Niklaus J.

2014-01-01

117

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

PubMed

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. PMID:25637417

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

2015-03-01

118

Population biology of the Norway lobster, Nephrops norvegicus (L.) in the Firth of Clyde, Scotland II: fecundity and size at onset of sexual maturity  

Microsoft Academic Search

Tuck, I. D., Atkinson, R. J. A., and Chapman, C. J. 2000. Population biology of the Norway lobster, Nephrops norvegicus (L.) in the Firth of Clyde, Scotland II: fecundity and size at onset of sexual maturity. - ICES Journal of Marine Science, 57: 1227-1239. The fecundity and size at onset of sexual maturity of Nephrops norvegicus was estimated at different

I. D. Tuck; R. J. A. Atkinson; C. J. Chapman

2000-01-01

119

Assessment of hydration status in a large population.  

PubMed

Both acute and chronic dehydration can have important implications for human behaviour and health. Young children, non-autonomous individuals and the elderly are at a greater risk of dehydration. Mild hypertonic dehydration could be related to less efficient cognitive and physical performance and has been reported to be associated with frequently occurring pathological conditions, especially nephrolithiasis. The assessment of hydration status in a large sample appears to be of interest for conducting epidemiological and large clinical studies aimed at improving preventive and curative care. Especially in large-population studies, methods that are used have to be accurate, cheap, quick and require no technical expertise. Body weight change is widely used to determine acute hydration changes, but seems to be insufficiently accurate in longitudinal studies. Bioimpedance analysis methods enable the assessment of total body water content, but their use is still under debate. Because plasma osmolality directly reflects intracellular osmolality, it constitutes a good marker to assess acute hydration changes, but not chronic hydration status because it changes constantly. Moreover, venepuncture is considered to be invasive and is not suitable for a large-sample study, especially in children. Urinary markers appear to be good alternatives for assessing hydration status in large populations. Collection of urine samples is non-invasive and cheap. High technical expertise is not required to perform urinary marker measurements and these measurements can be carried out quickly. Thus, methods based on urinary markers are very well suited for field studies. Urine colour is probably the least sensitive marker despite its high specificity. Urine osmolality and especially urine specific gravity could be easily used for determining hydration status in large-sample studies. PMID:25418739

Baron, Stephanie; Courbebaisse, Marie; Lepicard, Eve M; Friedlander, Gerard

2014-11-24

120

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

PubMed

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. PMID:17665300

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

2008-12-01

121

Response of human populations to large-scale emergencies  

NASA Astrophysics Data System (ADS)

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.

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

2010-03-01

122

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

SciTech Connect

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.

Mols, Floortje [CoRPS-Center of Research on Psychology in Somatic Diseases, Tilburg University, Tilburg (Netherlands); Comprehensive Cancer Centre South (CCCS), Eindhoven Cancer Registry, Eindhoven (Netherlands)], E-mail: F.Mols@uvt.nl; Korfage, Ida J. [Department of Public Health, Erasmus MC-University Medical Center, Rotterdam (Netherlands); Vingerhoets, Ad J.J.M. [Clinical Psychology Section, Tilburg University, Tilburg (Netherlands); Kil, Paul J.M. [Department of Urology, Sint Elisabeth Hospital, Tilburg (Netherlands); Coebergh, Jan Willem W. [Comprehensive Cancer Centre South (CCCS), Eindhoven Cancer Registry, Eindhoven (Netherlands); Department of Public Health, Erasmus MC-University Medical Center, Rotterdam (Netherlands); Essink-Bot, Marie-Louise [Department of Public Health, Erasmus MC-University Medical Center, Rotterdam (Netherlands); Department of Social Medicine, Academic Medical Centre, University of Amsterdam, Amsterdam (Netherlands); Poll-Franse, Lonneke V. van de [CoRPS-Center of Research on Psychology in Somatic Diseases, Tilburg University, Tilburg (Netherlands); Comprehensive Cancer Centre South (CCCS), Eindhoven Cancer Registry, Eindhoven (Netherlands)

2009-01-01

123

New insights into the variability of reproduction modes in European populations of Rubus subgen. Rubus: how sexual are polyploid brambles?  

PubMed

Rubus subgen. Rubus includes common European species with highly complicated taxonomy, ongoing hybridisation and facultative apomixis. Out of approximately 750 species recognised in Europe, only 3 diploid sexual species are known, along with numerous apomictic brambles that are highly connected to polyploidy. One exception of a tetraploid taxon is R. ser. Glandulosi, which is known for prevalent sexuality. This taxon highly hybridises with tetraploid members of R. ser. Discolores and leads to the origin of many hybridogenous populations and individuals. In this study, we verify reproduction modes in different diploid, triploid and tetraploid species of subgen. Rubus, with focus on taxa putatively involved in such hybridisation by applying flow cytometric seed screen analysis. We found 100 % sexuality of diploid species, whereas triploid species had obligate unreduced embryo sac development. In contrast, tetraploid plants had varying degrees of sexuality. Additionally, we discovered that R. bifrons has the ability to undergo a reproduction mode switch as a reaction to environmental conditions. These results provide insight into reproductive modes of European brambles and shed light on their reticulate evolution and speciation. PMID:23114637

Šarhanová, Petra; Vašut, Radim J; Dan?ák, Martin; Bureš, Petr; Trávní?ek, Bohumil

2012-12-01

124

Age at sexual maturity, sex ratio, fecundity, and longevity of isolated headwater populations of Westslope cutthroat trout  

USGS Publications Warehouse

We sampled 19 isolated headwater populations of westslope cutthroat trout Oncorhynchus clarki lewisi in Montana to provide estimates of fecundity, longevity, sex ratio, and age at sexual maturity. Fecundity was estimated for 31 fish collected from two streams in the upper Missouri River drainage. Females smaller than 149 mm fork length (FL) were generally immature and their fecundities could not be estimated. Mean fecundities (SD) were 227 eggs (41.1) for 150-174-mm fish, 346 eggs (85.6) for 175-199-mm fish, and 459 eggs (150.8) for 200-mm and larger fish. A linear regression model (two stream samples combined) to predict fecundity (E) from fork length was developed (E = -494.9 + 4.4.FL: r2 = 0.51, P < 0.001) for westslope cutthroat trout in the upper Missouri River drainage. Regression slopes of fecundity against fish length differed significantly (P < 0.01) between these and some of the previously studied populations. Steeper slopes were associated with lacustrine-adfluvial populations. The average sex ratio was 1.3 males per female across all sampled streams. Males began to mature sexually at age 2 and all were mature by age 4. Some females (27%) were sexually mature at age 3 and most of them (93%) were mature by age 5. Length was a better predictor of sexual maturity than age. Males matured at 110-160 mm and females at 150-180 mm FL. The maximum estimated age was 8 years based on otoliths from 475 fish collected from our 19 study streams and 14 additional streams.

Downs, C.C.; White, R.G.; Shepard, B.B.

1997-01-01

125

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

PubMed Central

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 males are high-quality prey. The results of these field experiments support the hypothesis that sexual cannibalism is adaptive to females. PMID:18941517

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

126

Speed of evolution in large asexual populations with diminishing returns.  

PubMed

The adaptive evolution of large asexual populations is generally characterized by competition between clones carrying different beneficial mutations. Interference slows down the adaptation speed and makes the theoretical description of the dynamics more complex with respect to the successional occurrence and fixation of beneficial mutations typical of small populations. A simplified modeling framework considering multiple beneficial mutations with equal and constant fitness advantage is known to capture some of the essential features of laboratory evolution experiments. However, in these experiments the relative advantage of a beneficial mutation is generally dependent on the genetic background. In particular, the general pattern is that, as mutations in different loci accumulate, the relative advantage of new mutations decreases, a trend often referred to as "diminishing return" epistasis. Here, we propose a phenomenological model that generalizes the fixed-advantage framework to include this negative epistasis in a simple way. We evaluate analytically as well as with direct simulations the quantitative consequences of diminishing returns on the evolutionary dynamics. The speed of adaptation decreases in time and reaches a limit value corresponding to neutral evolution in the long time limit. This corresponds to an increase of the diversity in terms of "classes of mutation" in the population. Finally, we show how the model can be compared with dynamic data on fitness and number of beneficial mutations from laboratory evolution experiments. PMID:25308509

Fumagalli, Maria R; Osella, Matteo; Thomen, Philippe; Heslot, Francois; Cosentino Lagomarsino, Marco

2015-01-21

127

Control of BRD in large dairy calf populations.  

PubMed

Bovine respiratory disease (BRD) is a leading cause of morbidity and mortality in dairy calves. As the number of calves being raised on the dairy farm or at a calf-raising operation has become larger, both opportunity and risk have increased. Opportunities for applying economies of size and scale exist in these large dairy calf populations while meeting specific needs of the dairy calf. BRD control requires effective biosecurity and biocontainment efforts, adequate passive transfer of immunoglobulins, a strategic immunization program, and appropriate diagnostic strategies for ongoing disease surveillance. These components are necessary to achieve an evidence-based approach for preventing and reducing severity of BRD cases. Proper nutrition, housing, and environmental management are important for achieving optimal dairy calf health and performance. Good record keeping and analysis of outcomes are needed to document dairy calf health and performance and to efficiently identify new problems that require attention in these large dairy calf populations. Proper management of calves to prevent and control BRD requires careful planning and follow through to achieve those results but will likely pay big dividends in improved calf health and future productivity. PMID:25497502

Lehenbauer, Terry W

2014-12-01

128

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

ERIC Educational Resources Information Center

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…

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

2004-01-01

129

Multivariate sexual selection on male song structure in wild populations of sagebrush crickets, Cyphoderris strepitans (Orthoptera: Haglidae)  

PubMed Central

While a number of studies have measured multivariate sexual selection acting on sexual signals in wild populations, few have confirmed these findings with experimental manipulation. Sagebrush crickets are ideally suited to such investigations because mating imposes an unambiguous phenotypic marker on males arising from nuptial feeding by females. We quantified sexual selection operating on male song by recording songs of virgin and mated males captured from three wild populations. To determine the extent to which selection on male song is influenced by female preference, we conducted a companion study in which we synthesized male songs and broadcast them to females in choice trials. Multivariate selection analysis revealed a saddle-shaped fitness surface, the highest peak of which corresponded to longer train and pulse durations, and longer intertrain intervals. Longer trains and pulses likely promote greater mate attraction, but selection for longer intertrain durations suggests that energetic constraints may necessitate “time outs”. Playback trials confirmed the selection for longer train and pulse durations, and revealed significant stabilizing selection on dominant frequency, suggesting that the female auditory system is tightly tuned to the species-specific call frequency. Collectively, our results revealed a complex pattern of multivariate nonlinear selection characterized primarily by strong stabilizing and disruptive selection on male song traits. PMID:24223293

Ower, Geoffrey D; Judge, Kevin A; Steiger, Sandra; Caron, Kyle J; Smith, Rebecca A; Hunt, John; Sakaluk, Scott K

2013-01-01

130

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

NASA Astrophysics Data System (ADS)

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.

Gutierrez A., Natalia A.

2014-06-01

131

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

PubMed Central

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

2013-01-01

132

Sexual behaviour.  

PubMed

Sexual health is not merely the absence of disease, but the ability to have informed, consensual, safe, respectful, and pleasurable sexual relationships. The majority of the population are sexually active, most with someone of the opposite sex. The frequency and range of sexual practices that people engage in declines with age, but for many, sexual activity continues well into later life. Different aspects of sexual health affect people at different times throughout their lives. As people in the UK tend to first have sex around the age of 16, but do not start living with a partner until much later, the avoidance of sexually transmitted infections and unplanned pregnancy is necessary for many for a number of years. As people get older, their sexual health needs change and they become more concerned with the impact of their general health on their ability to have sex. Some people experience non-volitional sex (sex against their will); although this occurs typically in late teenage it may affect women and men at any age and so requires consideration throughout life. As many people find it difficult to talk about sex and sexual health matters, health professionals should make sexual health enquiry a component of their holistic healthcare. PMID:24966786

Mercer, Catherine H

2014-06-01

133

A Population-Based Study of Cardiovascular Disease Risk in Sexual-Minority Women  

PubMed Central

Objectives. We sought to determine if sexual-minority women were at greater risk for cardiovascular disease (CVD) than their heterosexual counterparts. Methods. We aggregated data from the 2001–2008 National Health and Nutrition Examination Surveys to examine differences in CVD risk between heterosexual and sexual-minority women by using the Framingham General CVD Risk Score to calculate a ratio of vascular and chronological age. We also examined differences in the prevalence of various CVD risk factors. Results. Sexual-minority women were more likely to be current or former smokers, to report a history of drug use, to report risky drinking, and to report a family history of CVD. On average, sexual-minority women were 13.9% (95% confidence interval [CI]?=?8.5%, 19.3%) older in vascular terms than their chronological age, which was 5.7% (95% CI?=?1.5%, 9.8%) greater than that of their heterosexual counterparts. Family history of CVD and history of drug use were unrelated to increased CVD risk, and this risk was not fully explained by either risky drinking or smoking. Conclusions. Sexual-minority women are at increased risk for CVD compared with heterosexual women. PMID:23948018

Jabson, Jennifer M.; Bucholz, Kathleen K.; Bowen, Deborah J.

2013-01-01

134

Comment: On the consequences of sexual selection for fisheries-induced evolution  

E-print Network

COMMENT Comment: On the consequences of sexual selection for fisheries-induced evolution Davnah; Jørgensen et al. 2007). In recent years, evidence has also accumulated for a role of sexual selection populations fail to acknowledge the strength and the importance of sexual selection, relying largely on tempo

Cotton, Sam

135

drift and selection a) selection, no genetic drift b) large population, drift + selection  

E-print Network

1 drift and selection a) selection, no genetic drift b) large population, drift + selection c) small population, drift + selection nonrandom mating affects genotypic frequencies of a population continental "mainland" population to a smaller island population pt+1 = pt + m (pm - pt ) p = pt+1 - pt = m

Dever, Jennifer A.

136

Massive Uniform Manipulation: Controlling Large Populations of Simple Robots with a Common Input Signal  

E-print Network

Massive Uniform Manipulation: Controlling Large Populations of Simple Robots with a Common Input-- Roboticists, biologists, and chemists are now pro- ducing large populations of simple robots, but controlling-computation constraints. Direct human control of large populations seems even more challenging. In this paper we

Napp, Nils

137

Smoking Initiation, Tobacco Product Use, and Secondhand Smoke Exposure Among General Population and Sexual Minority Youth, Missouri, 2011–2012  

PubMed Central

Introduction Research indicates disparities in risky health behaviors between heterosexual and sexual minority (referred to as LGBQ; also known as lesbian, gay, bisexual, queer, and questioning) youth. Limited data are available for tobacco-use–related behaviors beyond smoking status. We compared data on tobacco age of initiation, product use, and secondhand smoke exposure between general population and LGBQ youth. Methods Data for general population youth were from the statewide, representative 2011 Missouri Youth Tobacco Survey, and data for LGBQ youth were from the 2012 Out, Proud and Healthy survey (collected at Missouri Pride Festivals). Age-adjusted Cochran-Mantel-Haenszel tests were used to examine differences between general population (N = 1,547) and LGBQ (N = 410) youth, aged 14 to 18 years. Logistic regression models identified variables associated with current smoking. Results The 2 groups differed significantly on many tobacco-use–related factors. General population youth initiated smoking at a younger age, and LGBQ youth did not catch up in smoking initiation until age 15 or 16. LGBQ youth (41.0%) soon surpassed general population youth (11.2%) in initiation and proportion of current smokers. LGBQ youth were more likely to use cigars/cigarillos, be poly-tobacco users, and be exposed to secondhand smoke (SHS) in a vehicle (for never smokers). Older age (odds ratio [OR] = 1.39, 95% confidence interval [95% CI] = 1.18–1.62), female sex (OR = 1.64, 95% CI = 1.13–2.37), LGBQ identity (OR = 3.86, 95% CI = 2.50–5.94), other tobacco product use (OR = 8.67, 95% CI = 6.01–12.51), and SHS exposure in a vehicle (OR = 5.97, 95% CI = 3.83–9.31) all significantly increased the odds of being a current smoker. Conclusion This study highlights a need for the collection of data on sexual orientation on youth tobacco surveys to address health disparities among LGBQ youth. PMID:24995655

McElroy, Jane A.; Everett, Kevin D.

2014-01-01

138

Contrasting Life Histories in Neighbouring Populations of a Large Mammal  

PubMed Central

Background A fundamental life history question is how individuals should allocate resources to reproduction optimally over time (reproductive allocation). The reproductive restraint hypothesis predicts that reproductive effort (RE; the allocation of resources to current reproduction) should peak at prime-age, whilst the terminal investment hypothesis predicts that individuals should continue to invest more resources in reproduction throughout life, owing to an ever-decreasing residual reproductive value. There is evidence supporting both hypotheses in the scientific literature. Methodology/Principal Findings We used an uncommonly large, 38 year dataset on Alpine chamois (Rupicapra rupicapra) shot at various times during the rutting period to test these two hypotheses. We assumed that body mass loss in rutting males was strongly related to RE and, using a process-based approach, modelled how male relative mass loss rates varied with age. For different regions of our study area, we provide evidence consistent with different hypotheses for reproductive allocation. In sites where RE declined in older age, this appears to be strongly linked to declining body condition in old males. In this species, terminal investment may only occur in areas with lower rates of body mass senescence. Conclusions/Significance Our results show that patterns of reproductive allocation may be more plastic than previously thought. It appears that there is a continuum from downturns in RE at old age to terminal investment that can be manifest, even across adjacent populations. Our work identifies uncertainty in the relationship between reproductive restraint and a lack of competitive ability in older life (driven by body mass senescence); both could explain a decline in RE in old age and may be hard to disentangle in empirical data. We discuss a number of environmental and anthropogenic factors which could influence reproductive life histories, underlining that life history patterns should not be generalised across different populations. PMID:22125651

Mason, Tom H. E.; Chirichella, Roberta; Richards, Shane A.; Stephens, Philip A.; Willis, Stephen G.; Apollonio, Marco

2011-01-01

139

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

ERIC Educational Resources Information Center

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…

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

2011-01-01

140

Male-male contests for mates, sexual size dimorphism, and sex ratio in a natural population of a solitary parasitoid.  

PubMed

Understanding how different behavioural and life history traits interact is fundamental to developing ethological theory. Here we study the interaction of male-male competition for mates and sexual size dimorphism in a solitary wasp, with implications for sex allocation. In Hymenoptera, females are normally larger than males suggesting that males do not benefit as much as females from larger size. However, in our focal species, a solitary Eurytoma wasp, males compete for mates by pairwise contests at female emergence sites, suggesting that male size may strongly affect fitness. In contests observed in the field, larger males were more likely to win fights, and males fighting at female emergence sites were much larger than average males. Males showed higher variance in body size than females, such that all the smallest individuals were males, a majority of medium-to-large individuals were female, but the majority of largest individuals were male. Our data suggest that sexual size dimorphism in this species has been affected by intra-sexual selection for male size, which may have implications for sex allocation. PMID:23872503

Macedo, Margarete V; Monteiro, Ricardo F; Silveira, Mariana P; Mayhew, Peter J

2013-11-01

141

Sexual activity, sexual dysfunction and associated help-seeking behaviours in middle-aged and older adults in Spain: a population survey  

Microsoft Academic Search

To study sexual activity, the prevalence of sexual dysfunction and related help-seeking behaviours among mature adults in\\u000a Spain, a telephone survey was conducted in Spain in 2001–2002. This was completed by 750 men and 750 women aged 40–80 years.\\u000a Eighty-eight percent of men and 66% of women had engaged in sexual intercourse during the 12 months preceding the interview.\\u000a Early ejaculation (31%)

Edson D. Moreira; Dale B. Glasser; Clive Gingell

2005-01-01

142

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

PubMed

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. PMID:25403321

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

2014-11-18

143

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

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. PMID:24780361

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

2014-01-01

144

Oral potentially malignant disorders in a large dental population.  

PubMed

Objectives Oral cancer (OC) may be preceded by clinically evident oral potentially malignant disorders (OPMDs). Oral carcinogenesis is a multistep process that begins as epithelial hyperplasia and progresses to oral epithelial dysplasia and finally to fully malignant phenotypes. The aim of our study was to estimate the prevalence of OPMDs in a large population of dental patients. Methods Patients were seen in the Oral Diagnosis and Oral Medicine clinics at Boston University Henry M. Goldman School of Dental Medicine between July 2013 and February 2014 and received a comprehensive oral examination to identify any possible mucosal lesions. Patients with a suspected OPMD (submucous fibrosis, oral lichen planus, leukoplakia and erythroplakia) that did not resolve in 2-3 weeks received a biopsy for definitive diagnosis. Logistic regression models were used to explore the relationship between OPMDs and associated risk factors. Results A total of 3,142 patients received a comprehensive oral examination [median age: 43 (range: 18-97); 54.3% females]. Among these, 4.5% had an oral mucosal lesion with 0.9% being an OPMD (one submucous fibrosis, three epithelial dysplasias, fourteen with hyperkeratosis/epithelial hyperplasia and nine with oral lichen planus). Males and current smokers were associated with higher odds of having OPMD (OR 1.7, 95% CI 0.8-3.8; OR 1.9, 95%CI 0.8-4.1). Increasing age was associated with having OPMDs (p<0.01). Conclusion Optimal oral visual screening for OC remains a simple and essential tool to identify any suspicious lesions and potentially increase survival. Although OPMDs were rare, our results confirm the importance of a thorough chairside screening by dentists and dental students to detect any mucosal changes. PMID:25591015

Villa, Alessandro; Gohel, Anita

2014-12-01

145

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

PubMed Central

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 men and women and homosexual men, but not homosexual women, are daily smokers to a higher extent than heterosexuals. Only for the “other” sexual orientation group the odds ratios of daily smoking were reduced to not significant levels after adjustments for covariates including trust and social participation. PMID:24903892

2014-01-01

146

Amyloid ? precursor protein regulates male sexual behavior  

PubMed Central

Sexual behavior is variable between individuals, ranging from celibacy to sexual addictions. Within normal populations of individual men, ranging from young to middle aged, testosterone levels do not correlate with libido. To study the genetic mechanisms that contribute to individual differences in male sexual behavior, we used hybrid B6D2F1 male mice, which are a cross between two common inbred strains (C57BL/6J and DBA/2J). Unlike most laboratory rodent species in which male sexual behavior is highly dependent upon gonadal steroids, sexual behavior in a large proportion of these hybrid male mice after castration is independent of gonadal steroid hormones and their receptors; thus, we have the ability to discover novel genes involved in this behavior. Gene expression arrays, validation of gene candidates, and transgenic mice that over-express one of the genes of interest were utilized to reveal genes involved in maintenance of male sexual behavior. Several genes related to neuroprotection and neurodegeneration were differentially expressed in the hypothalamus of males that continued to mate after castration. Male mice over-expressing the human form of one of these candidate genes, amyloid beta precursor protein (APP), displayed enhanced sexual behavior prior to castration and maintained sexual activity for a longer duration after castration as compared with controls. Our results reveal a novel and unexpected relationship between APP and male sexual behavior. We speculate that declining APP during normal aging in males may contribute to the loss of sexual function. PMID:20668181

Park, Jin Ho; Bonthius, Paul; Tsai, Houng-Wei; Bekiranov, Stefan; Rissman, Emilie F.

2010-01-01

147

Sexually transmitted infections and vaginal douching in a population of female sex workers in Nairobi, Kenya  

PubMed Central

Objective: To assess the association between vaginal douching and sexually transmitted infections (STI) among a group of female sex workers (FSWs) in Nairobi, Kenya. Methods: This study was part of a randomised, placebo controlled trial of monthly prophylaxis with 1 g of azithromycin to prevent STIs and HIV infection in a cohort of Nairobi FSWs. Consenting women were administered a questionnaire and screened for STIs. Results: The seroprevalence of HIV-1 among 543 FSWs screened was 30%. HIV infection was significantly associated with bacterial vaginosis (BV), trichomoniasis, gonorrhoea, and the presence of a genital ulcer. Regular douching was reported by 72% of the women, of whom the majority inserted fluids in the vagina, generally after each sexual intercourse. Water with soap was the fluid most often used (81%), followed by salty water (18%), water alone (9%), and a commercial antiseptic (5%). Douching in general and douching with soap and water were significantly associated with bacterial vaginosis (p = 0.05 and p = 0.04 respectively). There was a significant trend for increased frequency of douching and higher prevalence of BV. There was no direct relation observed between douching and risk for HIV infection or other STIs. Conclusion: The widespread habit of douching among African female sex workers was confirmed. The association between vaginal douching and BV is of concern, given the increased risk of HIV infection with BV, which has now been shown in several studies. It is unclear why we could not demonstrate a direct association between douching and HIV infection. Further research is required to better understand the complex relation between douching, risk for bacterial vaginosis, and risk for HIV and other STIs. Key Words: vaginal douching; sexually transmitted infections; female sex workers PMID:11463927

Fonck, K; Kaul, R; Keli, F; Bwayo, J; Ngugi, E; Moses, S; Temmerman, M

2001-01-01

148

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

PubMed Central

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

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

2012-01-01

149

Prevalence of Consensual Male–Male Sex and Sexual Violence, and Associations with HIV in South Africa: A Population-Based Cross-Sectional Study  

PubMed Central

Background In sub-Saharan Africa the population prevalence of men who have sex with men (MSM) is unknown, as is the population prevalence of male-on-male sexual violence, and whether male-on-male sexual violence may relate to HIV risk. This paper describes lifetime prevalence of consensual male–male sexual behavior and male-on-male sexual violence (victimization and perpetration) in two South African provinces, socio-demographic factors associated with these experiences, and associations with HIV serostatus. Methods and Findings In a cross-sectional study conducted in 2008, men aged 18–49 y from randomly selected households in the Eastern Cape and KwaZulu-Natal provinces provided anonymous survey data and dried blood spots for HIV serostatus assessment. Interviews were completed in 1,737 of 2,298 (75.6%) of enumerated and eligible households. From these households, 1,705 men (97.1%) provided data on lifetime history of same-sex experiences, and 1,220 (70.2%) also provided dried blood spots for HIV testing. 5.4% (n?=?92) of participants reported a lifetime history of any consensual sexual activity with another man; 9.6% (n?=?164) reported any sexual victimization by a man, and 3.0% (n?=?51) reported perpetrating sexual violence against another man. 85.0% (n?=?79) of men with a history of consensual sex with men reported having a current female partner, and 27.7% (n?=?26) reported having a current male partner. Of the latter, 80.6% (n?=?21/26) also reported having a female partner. Men reporting a history of consensual male–male sexual behavior are more likely to have been a victim of male-on-male sexual violence (adjusted odds ratio [aOR]?=?7.24; 95% CI 4.26–12.3), and to have perpetrated sexual violence against another man (aOR?=?3.10; 95% CI 1.22–7.90). Men reporting consensual oral/anal sex with a man were more likely to be HIV+ than men with no such history (aOR?=?3.11; 95% CI 1.24–7.80). Men who had raped a man were more likely to be HIV+ than non-perpetrators (aOR?=?3.58; 95% CI 1.17–10.9). Conclusions In this sample, one in 20 men (5.4%) reported lifetime consensual sexual contact with a man, while about one in ten (9.6%) reported experience of male-on-male sexual violence victimization. Men who reported having had sex with men were more likely to be HIV+, as were men who reported perpetrating sexual violence towards other men. Whilst there was no direct measure of male–female concurrency (having overlapping sexual relationships with men and women), the data suggest that this may have been common. These findings suggest that HIV prevention messages regarding male–male sex in South Africa should be mainstreamed with prevention messages for the general population, and sexual health interventions and HIV prevention interventions for South African men should explicitly address male-on-male sexual violence. Please see later in the article for the Editors' Summary PMID:23853554

Dunkle, Kristin L.; Jewkes, Rachel K.; Murdock, Daniel W.; Sikweyiya, Yandisa; Morrell, Robert

2013-01-01

150

The Multidimensional Scale of Sexuality.  

PubMed

Research on the assessment of sexual orientation has been limited, and what does exist is often conflicting and confusing. This is largely due to the lack of any agreed upon definition of bisexuality. The Multidimensional Scale of Sexuality (MSS) was developed to validate and to contrast six proposed categories of bisexuality, as well as categories related to heterosexuality, homosexuality, and asexuality. This instrument includes ratings of the behavioral and cognitive/affective components of sexuality. The MSS was completed by 148 subjects, the majority of whom were from identified homosexual and bisexual populations. Although subjects' self-descriptions on the MSS were consistent with their self-descriptions on the Kinsey Heterosexual-Homosexual Scale, the MSS provided a more varied description of sexual orientation. Subject's self-described sexual orientation on the MSS was more consistent with their cognitive/affective ratings than with their behavioral ratings. With the exception of self-described heterosexuals, the frequency of cognitive/affective sexuality was greater than that of behavioral sexuality. PMID:2230111

Berkey, B R; Perelman-Hall, T; Kurdek, L A

1990-01-01

151

Highly Active Antiretroviral Therapy is Associated with Decreased Incidence of Sexually Transmitted Diseases in a Taiwanese HIV-Positive Population  

PubMed Central

Abstract 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. PMID:23442028

Cheng, Shu-Hsing; Yang, Chin-Hui

2013-01-01

152

Sexual Assault  

MedlinePLUS

... assault fact sheet Sexual assault fact sheet ePublications Sexual assault fact sheet Print this fact sheet Sexual assault ... assaulted? More information on sexual assault What is sexual assault? Sexual assault and abuse is any type of ...

153

Sexual Health  

MedlinePLUS

... Sexual Attraction and Orientation Sexual Harassment and Sexual Bullying Talking to Your Partner About Condoms Tampons, Pads, ... Sexual Attraction and Orientation Sexual Harassment and Sexual Bullying Talking to Your Partner About Condoms Testicular Exams ...

154

SEXUAL ABUSE IN CALIFORNIA PRISONS: How the California Rape Shield Fails the Most Vulnerable Populations  

E-print Network

ransgender prisoners [are placed] in the general populationPrisoners and Parolees, Civil Narcotic Addicts and Outpa- tients and Other Populationspopulation. This cost is concentrated most heavily in the persons, households, and communities of prisoners and

Hill, Tasha

2014-01-01

155

Nash Certainty Equivalence in Large Population Stochastic Dynamic Games: Connections with the  

E-print Network

Nash Certainty Equivalence in Large Population Stochastic Dynamic Games: Connections;Brief Historic Background: Prisoner's Dilemma A Very Simple Model with a Rich Structure: Two criminal(n): the population driving term z(n) = 1 n n i=1 zi ui: control wi: noise (a standard Wiener process) n: population

Huang, Minyi

156

Population structure of lake trout (Salvelinus namaycush) in a large glacial-fed lake inferred  

E-print Network

Population structure of lake trout (Salvelinus namaycush) in a large glacial-fed lake inferred from Columbia, Canada, and contains relatively pristine populations of lake trout (Salvelinus namaycush, et il contient des populations de touladis (Salvelinus namaycush) encore relativement dans leur e

Taylor, Eric B. "Rick"

157

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

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.

Dodd, C.K., Jr.

1997-01-01

158

Student understanding in mechanics: A large population survey  

NSDL National Science Digital Library

There has recently been a considerable growth in research probing student understanding in mechanics. Questions based on four such research probes were included in the end-of-high-school physics examination undertaken by some 5500 students. The results obtained give an indication of the extent to which various interpretations of some physical situations are held in a whole population. The possibilities of using research probes as a basis for assessment questions are also illustrated.

Gunstone, Richard

2005-10-20

159

Super-individuals a simple solution for modelling large populations on an individual basis  

Microsoft Academic Search

Modelling populations on an individual-by-individual basis has proven to be a fruitful approach. Many complex patterns that are observed on the population level have been shown to arise from simple interactions between individuals. However, a major problem with these models is that the typically large number of individuals needed requires impractically large computation times. The common solution, reduction of the

M. Scheffer; J. M. Baveco; D. L. DeAngelis; K. A. Rose; E. H. van Nes

1995-01-01

160

Sexuality and Dementia  

MedlinePLUS

... chronic illness. "No one asked me about my marriage or sexuality. Yet it plays a large part ... masturbation or pursuing a sexual relationship outside the marriage. One caregiver shared that she sometimes has sex ...

161

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

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. PMID:23872504

Sukumaran, Sandhya; Grant, Alastair

2013-09-18

162

Populations and determinants of airborne fungi in large office buildings.  

PubMed Central

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

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

2002-01-01

163

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

PubMed

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. PMID:23662464

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

2013-01-01

164

Do pre- and post-copulatory sexually selected traits covary in large herbivores?  

PubMed Central

Background In most species, males compete to gain both matings (via pre-copulatory competition) and fertilizations (via post-copulatory competition) to maximize their reproductive success. However, the quantity of resources devoted to sexual traits is finite, and so males are predicted to balance their investment between pre- and post-copulatory expenditure depending on the expected pay-offs that should vary according to mating tactics. In Artiodactyla species, males can invest in weapons such as horns or antlers to increase their mating gains or in testes mass/sperm dimensions to increase their fertilization efficiency. Moreover, it has been suggested that in these species, males with territory defence mating tactic might preferentially increase their investment in post-copulatory traits to increase their fertilization efficiency whereas males with female defence mating tactic might increase their investment in pre-copulatory sexually selected traits to prevent other males from copulating with females. In this study, we thus test the prediction that male’s weapon length (pre-copulatory trait) covaries negatively with relative testes size and/or sperm dimensions (post-copulatory traits) across Artiodactyla using a phylogenetically controlled framework. Results Surprisingly no association between weapon length and testes mass is found but a negative association between weapon length and sperm length is evidenced. In addition, neither pre- nor post-copulatory traits were found to be affected by male mating tactics. Conclusions We propose several hypotheses that could explain why male ungulates may not balance their reproductive investment between pre- and post-copulatory traits. PMID:24716470

2014-01-01

165

Collective response of human populations to large-scale emergencies  

E-print Network

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.

Bagrow, James P; Barabási, Albert-László; 10.1371/journal.pone.0017680

2011-01-01

166

Collective response of human populations to large-scale emergencies.  

PubMed

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. PMID:21479206

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

2011-01-01

167

Collective Response of Human Populations to Large-Scale Emergencies  

PubMed Central

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. PMID:21479206

Barabási, Albert-László

2011-01-01

168

Detecting differential protein expression in large-scale population proteomics  

SciTech Connect

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.

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

2014-06-17

169

Effect of elevation on sexual reproduction in alpine populations of Saxifraga oppositifolia (Saxifragaceae)  

Microsoft Academic Search

Self-compatibility in high arctic and alpine areas is regarded as an adaptation to low pollinator abundance. However, high\\u000a genetic variability as a consequence of outcrossing is, with regard to population persistence, favorable in highly stochastic\\u000a environments such as tundra habitats. To evaluate these contradictory scenarios, I performed in situ pollination experiments\\u000a to examine the breeding system of the predominant outcrosser

Felix Gugerli

1998-01-01

170

Lesbian, Gay, Bisexual, and Transgender Hate Crimes and Suicidality Among a Population-Based Sample of Sexual-Minority Adolescents in Boston  

PubMed Central

Objectives. We examined whether past-year suicidality among sexual-minority adolescents was more common in neighborhoods with a higher prevalence of hate crimes targeting lesbian, gay, bisexual, and transgender (LGBT) individuals. Methods. Participants’ data came from a racially/ethnically diverse population-based sample of 9th- through 12th-grade public school students in Boston, Massachusetts (n?=?1292). Of these, 108 (8.36%) reported a minority sexual orientation. We obtained data on LGBT hate crimes involving assaults or assaults with battery between 2005 and 2008 from the Boston Police Department and linked the data to the adolescent’s residential address. Results. Sexual-minority youths residing in neighborhoods with higher rates of LGBT assault hate crimes were significantly more likely to report suicidal ideation (P?=?.013) and suicide attempts (P?=?.006), than were those residing in neighborhoods with lower LGBT assault hate crime rates. We observed no relationships between overall neighborhood-level violent and property crimes and suicidality among sexual-minority adolescents (P?>?.05), providing evidence for specificity of the results to LGBT assault hate crimes. Conclusions. Neighborhood context (i.e., LGBT hate crimes) may contribute to sexual-orientation disparities in adolescent suicidality, highlighting potential targets for community-level suicide-prevention programs. PMID:24328619

Hatzenbuehler, Mark L.

2014-01-01

171

Determining asymptotically large population sizes in insect swarms.  

PubMed

Social animals commonly form aggregates that exhibit emergent collective behaviour, with group dynamics that are distinct from the behaviour of individuals. Simple models can qualitatively reproduce such behaviour, but only with large numbers of individuals. But how rapidly do the collective properties of animal aggregations in nature emerge with group size? Here, we study swarms of Chironomus riparius midges and measure how their statistical properties change as a function of the number of participating individuals. Once the swarms contain order 10 individuals, we find that all statistics saturate and the swarms enter an asymptotic regime. The influence of environmental cues on the swarm morphology decays on a similar scale. Our results provide a strong constraint on how rapidly swarm models must produce collective states. But our findings support the feasibility of using swarms as a design template for multi-agent systems, because self-organized states are possible even with few agents. PMID:25121646

Puckett, James G; Ouellette, Nicholas T

2014-10-01

172

Sexual Health  

MedlinePLUS

... Parents can help their adolescent make healthy choices Sexual Health News & Information Understanding Sexual Health Public Health Reports ... infectious diseases, reproductive health and sexual violence prevention. Sexual Health Topics Sexually Transmitted Diseases Up-to-date information ...

173

CONSTRAINTS ON THE EVOLUTION OF MALES AND SEXUAL DIMORPHISM: FIELD ESTIMATES OF GENETIC ARCHITECTURE OF REPRODUCTIVE TRAITS IN THREE POPULATIONS OF GYNODIOECIOUS FRAGARIA VIRGINIANA  

Microsoft Academic Search

To understand how genetic constraints may limit the evolution of males and sexual dimorphism in a gynodioecious species, I conducted a quantitative genetic experiment in a gynodioecious wild strawberry, Fragaria virginiana. I estimated and compared genetic parameters (narrow-sense heritabilities, between-trait and between-sex genetic correlations, as well as phenotypic and genetic variance-covariance matrices) in the two sex morphs from three populations

Tia-Lynn Ashman

2003-01-01

174

Rapid assessment of drug use and sexual HIV risk patterns among vulnerable drugusing populations in Cape Town, Durban and Pretoria, South Africa  

Microsoft Academic Search

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

Charles Parry; Petal Petersen; Tara Carney; Sarah Dewing; Richard Needle

2008-01-01

175

Natural and sexual selection on male behaviour and morphology, and female choice in a wild field cricket population: spatial, temporal and analytical components  

Microsoft Academic Search

We used multiple regression, path analysis and non-parametric selection surface visualisation to investigate natural and sexual\\u000a selection and, in addition, cross-sectional female choice statistics to analyse female choice in a wild population of the\\u000a field cricket Gryllus campestris L. in central Germany. Adults (167 males, 75 females) were individually marked and followed daily over the entire adult stage.\\u000a Two morphological

Markus S. Ritz; Günter Köhler

2010-01-01

176

Approach to pain management in a large outpatient clinic population.  

PubMed

Though it is our ethical imperative to minimize discomfort, physicians often struggle to manage pain effectively, mainly due to time constraints, lack of training, and fear of litigation regarding over-prescribing of controlled substances. In addition, physicians also now must face potential litigation for under treatment of persistent pain. This dilemma often leaves the physician with a sense of insecurity and stress. We have provided a brief review of our approach to seek improvement in excluding substance abusers/drug diverters from those in need of aggressive pain management in the internal medicine outpatient clinics of a teaching institution. Multiple combined treatment modalities are usually employed, including physical interventions, evaluation and treatment of concomitant depression and psychosocial issues, pain modulators and analgesics, and consultations as indicated by clinical presentation. Experience and intuition are required in many cases. In our large volume, high complexity clinic setting, we continue to pursue guidelines to improve and streamline screening for substance abuse or the potential for abuse, particularly in younger individuals. In the elderly, since abuse potential is less likely and disease documentation is often more readily apparent, we feel relatively comfortable in initiating careful prescribing of opioid therapy early on. As we become more adept at our approach toward pain management issues, we will attempt some assessment of outcomes by observing changes in several parameters, including numbers of opioid prescriptions and comparative adequacy of pain control over time. National and local pain/addiction information and referral resources are available as follows: http:// www.nationalsubstanceabuseindex .org and http://www.wvupc. org/charleston/painlist. PMID:21932757

McJunkin, Brittain; Riley, Mary Ann; Lilly, J K; Casto, Amy; Bowe, Adina

2010-01-01

177

Sleep Patterns and Predictors of Disturbed Sleep in a Large Population of College Students  

Microsoft Academic Search

PurposeTo characterize sleep patterns and predictors of poor sleep quality in a large population of college students. This study extends the 2006 National Sleep Foundation examination of sleep in early adolescence by examining sleep in older adolescents.

Hannah G. Lund; Brian D. Reider; Annie B. Whiting; J. Roxanne Prichard

2010-01-01

178

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

PubMed Central

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

2012-01-01

179

A stochastic model of evolutionary dynamics with deterministic large-population asymptotics  

E-print Network

A stochastic model of evolutionary dynamics with deterministic large-population asymptotics Burton-diffusion equation Reactive strategies Iterated prisoner's dilemma a b s t r a c t An evolutionary birth on their local population density. Agents' individual evolutionary trajectories in X and S are governed

Simon, Burt

180

Daphnias: from the individual based model to the large population equation  

E-print Network

Daphnias: from the individual based model to the large population equation J.A.J.(Hans) Metz The class of deterministic 'Daphnia' models treated by Diekmann et al. (J Math Biol 61: 277­318, 2010) has a general size-structured consumer population ('Daphnia') and an unstruc- tured resource ('algae

Paris-Sud XI, Université de

181

Lipoprotein lipase gene polymorphism, cholesterol subfractions and myocardial infarction in large samples of the general population  

Microsoft Academic Search

a ¨ Abstract Objective: Genetic variants of the lipoprotein lipase gene have been associated with dyslipidemia and coronary artery disease. However, data have been inconsistent and are mainly based on selected predominantly male patient groups. Methods: We evaluated the influence of the HindIII restriction fragment length polymorphism on lipid levels in the general population (1361 participants of a large population-based

Stephan R. Holmer; Christian Hengstenberg; Bjorn Mayer; Angela Doring; Hannelore Lowel; Susanne Engel; Hans-Werner Hense; Melanie Wolf; Gernot Klein; Gunter A. J. Riegger; Heribert Schunkert

182

High genetic variation in leopards indicates large and long-term stable effective population size  

Microsoft Academic Search

In this paper we employ recently developed statistical and molecular tools to analyse the population history of the Tanzanian leopard ( Panthera pardus ), a large solitary felid. Because of their solitary lifestyle little is known of their past or present population dynamics. Eighty-one individuals were scored at 18 microsatellite loci. Overall, levels of hetero- zygosity were high (0.77 ?

G. Spong; M. Johansson; M. Björklund

2000-01-01

183

Sexuality and breast cancer: prime time for young patients  

PubMed Central

Sexuality and sexual functioning is a cardinal domain of health-related quality of life in breast cancer patients, namely in the younger population. Young women below 40 years of age go through a time in their lives where sexual self-identity has recently matured, their professional obligations are demanding and they bear interpersonal and childbearing expectations, all of which can suffer a devastating turnaround with cancer diagnosis and its physical and psychological aftermath. Although these women’s sexuality and directed interventions have remained largely unaddressed so far, concepts are evolving and treatment options are becoming diversified, chiefly on the field of non-hormonal pharmacological therapy of sexual dysfunction. This review will examine the definitions of female sexual dysfunction, the etiology of the disorders in young breast cancer patients, the assessment methods, the non-pharmacological and pharmacological treatment options and the challenges that lie ahead. PMID:23819031

2013-01-01

184

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

ERIC Educational Resources Information Center

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…

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

2008-01-01

185

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

ERIC Educational Resources Information Center

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…

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

1996-01-01

186

Prevalence of Chronic Obstructive Pulmonary Disease in China A Large, Population-based Survey  

Microsoft Academic Search

Rationale: The prevalence of chronic obstructive pulmonary disease (COPD) in China is largely unknown. Objectives: To obtain the COPD prevalence in China through a large- population, spirometry-based, cross-sectional survey of COPD. Methods: Urban and rural population-based cluster samples were randomlyselectedfromsevenprovinces\\/cities.Allresidents40years of age or older in the selected clusters were interviewed with a stan- dardized questionnaire revised from the international BOLD

Nanshan Zhong; Chen Wang; Wanzhen Yao; Ping Chen; Jian Kang; Shaoguang Huang; Baoyuan Chen; Changzheng Wang; Diantao Ni; Yumin Zhou; Shengming Liu; Xiaoping Wang; Dali Wang; Jiachun Lu; Jingping Zheng; Pixin Ran

187

Medical Consequences of Child Sexual Abuse: Commentary.  

ERIC Educational Resources Information Center

This commentary on a previous article (EC 619 261) about medical consequences of child sexual abuse urges prospective studies using large populations to evaluate many variables, as well as selection of projects which are most likely to influence practice or policy and thus affect significant numbers of persons. (DB)

Chadwick, David L.

1998-01-01

188

Sexually coercive behavior following childhood maltreatment.  

PubMed

Child maltreatment is associated with adult sexually coercive behavior. The association may be causal or confounders that increase the risk of both childhood victimization and sexually coercive behavior might explain the observed links. We examined if childhood maltreatment was related to sexual coercion independently of familial (genetic or common family environment) risk factors, thereby addressing potential causality. Participants were 6,255 18 to 33-year-old twins from the Finnish population-based study "Genetics of Sex and Aggression" who responded to self-report questionnaires of child maltreatment and sexually coercive behavior. We used generalized estimating equations to elucidate risk of sexual coercion in maltreated compared to unrelated, non-maltreated individuals. To adjust for unmeasured familial factors, we used the co-twin control method and compared sexual coercion risk within maltreatment-discordant twin pairs. Further, we examined possible differential effects of maltreatment subtypes and compared mean differences in maltreatment summary scores between sexually coercive individuals and controls. Sexual coercion was moderately more common among individuals maltreated as children versus unrelated controls (38.3 vs. 22.8 %; age- and gender-adjusted odds ratio, aOR = 2.31, 95 % CI 1.75-3.05) and the risk increase remained similar within maltreatment-discordant twins (OR = 2.82, 95 % CI 1.42-5.61). Moreover, different maltreatment subtypes predicted sexual coercion equally well and effect sizes remained similar within discordant twin pairs. We conclude that associations between child maltreatment and sexual coercion are largely independent of shared familial confounds, consistent with a causal inference. Importantly, detection and targeted interventions for maltreated children should remain a priority to reduce societal sexually coercive behavior. PMID:24752790

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

2015-01-01

189

Parasite mediated selection, sex and diapause in a natural population of Daphnia   

E-print Network

Parasites are thought to have large effects on their host populations, driving genetic change, population density changes, speciation and be a major selective force maintaining sexual reproduction. Indirect signatures of parasite-mediated selection...

Duncan, Alison B

190

Using a "Classroom Response System" to Improve Active Student Participation in a Large Sexual Health Class  

ERIC Educational Resources Information Center

Larger class sizes are often the solution to the greater enrollments and fewer resources that many colleges and universities face today. These large classes present special challenges to courses that were typically and most effectively taught in small, interactive and open settings. A "Classroom Response System" (CRS), an instructional tool that…

Vail-Smith, Karen; Blumell, Charla; Elmore, Barry

2006-01-01

191

Interpersonal Mistreatment in the Workplace: The Interface and Impact of General Incivility and Sexual Harassment  

Microsoft Academic Search

This article examined the relationships and outcomes of behaviors falling at the interface of general and sexual forms of interpersonal mistreatment in the workplace. Data were collected with surveys of two different female populations (Ns = 833 and 1,425) working within a large public-sector organization. Findings revealed that general incivility and sexual harassment were related constructs, with gender harassment bridging

Sandy Lim; Lilia M. Cortina

2005-01-01

192

Montane refugia predict population genetic structure in the Large-blotched Ensatina salamander  

E-print Network

Montane refugia predict population genetic structure in the Large-blotched Ensatina salamander in the Large-blotched Ensatina (Ensatina eschscholtzii klauberi), a plethodon- tid salamander endemic to middle and northern Baja California. A compos- ite SDM representing the range through time predicts two disjunct

McGuire, Jimmy A.

193

NASH EQUILIBRIA FOR LARGE-POPULATION LINEAR STOCHASTIC SYSTEMS OF WEAKLY  

E-print Network

social, economic, and engineering models, the individuals or agents involved have conflicting objectives of agents in many social, economic and manmade systems; however, in a large-scale dynamic modelChapter 1 NASH EQUILIBRIA FOR LARGE-POPULATION LINEAR STOCHASTIC SYSTEMS OF WEAKLY COUPLED AGENTS

Huang, Minyi

194

Sexual addiction, sexual compulsivity, sexual impulsivity, or what? Toward a theoretical model  

Microsoft Academic Search

We critically review the concepts of sexual addiction, sexual compulsivity, and sexual impulsivity and discuss their theoretical bases. A sample of 31 self?defined sex addicts was assessed by means of interview and questionnaires and compared with a large age?matched control group. A tendency to experience increased sexual interest in states of depression or anxiety was strongly characteristic of the sex

John Bancroft; Zoran Vukadinovic

2004-01-01

195

Sexual competitiveness and compatibility between mass-reared sterile flies and wild populations of Anastrepha Ludens (Diptera: Tephritidae) from different regions in Mexico  

SciTech Connect

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. (author) [Spanish] La colonia actualmente usada para controlar la mosca mexicana de la fruta, Anastrepha ludens (Loew), en Mexico tiene mas de 10 anos en cria masiva. Los insectos esteriles son liberados en una gran variedad de condiciones ambientales como parte de un control integrado para suprimir diversas poblaciones de esta plaga dentro de la Republica Mexicana. El objetivo de este documento esta dirigido a revisar el desempeno de las moscas esteriles frente a poblaciones silvestres procedentes de diferentes ambientes y para esto se realizaron comparaciones de compatibilidad y competitividad sexual de las moscas esteriles contra poblaciones silvestres de seis estados representativos de la Republica Mexicana: Nuevo Leon, Tamaulipas, Sinaloa, Nayarit, Michoacan y Chiapas. Los resultados obtenidos manifiestan diferencias en el horario de inicio de llamado y mayor actividad sexual del macho entre las moscas provenientes de cada estado. Sin embargo el indice de aislamiento (ISI) reflejo compatibilidad sexual entre la cepa de laboratorio y todas las poblaciones analizadas, indicando que los individuos esteriles pueden aparearse satisfactoriamente con las poblaciones silvestres de los seis estados. El indice de efectividad de apareamiento del macho (MRPI) reflejo de manera global que los machos esteriles son tan efectivos para copular como los silvestres. El indice de efectividad de apareamiento de la hembra (FRPI) reflejo que en la mayoria de los estados las hembras silvestres copularon en mayor proporcion que las hembras esteriles, excepto para las poblaciones de Tamaulipas y Chiapas. En general, la baja participacion de las hembras esteriles en el campo permitio al macho esteril ampliar su probabilidad de apareamiento con las hembras silvestres. En cuanto al indice de esterilidad relativa (RSI), observamos que la aceptacion de las hembras silvestres al macho esteril (25-55%) fue similar a la de los machos silvestres. Las hembras de la poblacion de Chiapas registro la menor aceptacion. Finalmente, los resultados obtenidos en la prueba de Fried, la cual determi

Orozco-Davila, D.; Hernandez, R.; Meza, S.; Dominguez, J. [Programa Moscamed Moscafrut-Desarrollo de Metodos, Central Poniente No. 14 altos-Esq. 2a Avenida Sur. CP 30700 Tapachula, Chiapas (Mexico)

2007-03-15

196

Constraints on the evolution of males and sexual dimorphism: field estimates of genetic architecture of reproductive traits in three populations of gynodioecious Fragaria virginiana.  

PubMed

To understand how genetic constraints may limit the evolution of males and sexual dimorphism in a gynodioecious species, I conducted a quantitative genetic experiment in a gynodioecious wild strawberry, Fragaria virginiana. I estimated and compared genetic parameters (narrow-sense heritabilities, between-trait and between-sex genetic correlations, as well as phenotypic and genetic variance-covariance matrices) in the two sex morphs from three populations grown in a common field garden. I measured pollen and ovule production per flower, petal size, fruit set, and flower number. My major findings are as follows. (1) The presence of a phenotypic trade-off between pollen production and fruit set in hermaphrodites reflects a negative genetic correlation in the narrow sense that is statistically significant when pooled across populations. (2) The main constraints on the evolution of males are low genetic variation for pollen per flower and strong positive correlations associated with ovule number (e.g., between pollen and ovules in hermaphrodites, and between ovules in hermaphrodites and females). (3) Traits with the lowest levels of sexual dimorphism (ovule number and flower number) have the highest between-sex genetic correlations suggesting that overlap in the expression of genes in the sex morphs constrains their independent evolution. (4) There are significant differences in G matrices between sex morphs but not among populations. However, evidence that male-female trait correlations in hermaphrodites were lower in populations with higher frequencies of females may indicate subtle changes in genetic architecture. PMID:14575323

Ashman, Tia-Lynn

2003-09-01

197

A trade-off between sexual signalling and immune function in a natural population of the drumming wolf spider Hygrolycosa rubrofasciata.  

PubMed

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. PMID:16033571

Ahtiainen, J J; Alatalo, R V; Kortet, R; Rantala, M J

2005-07-01

198

Sexual Assault  

MedlinePLUS

... for Patients Share This Page: Sexual Assault Resources Sexual Assault Sexual assault is a significant problem affecting American ... National Network at 1-800-656-HOPE (4673). Sexual Assault Examinations It is important to know that a ...

199

Sexual selection and natural selection in bird speciation  

PubMed Central

The role of sexual selection in speciation is investigated, addressing two main issues. First, how do sexually selected traits become species recognition traits? Theory and empirical evidence suggest that female preferences often do not evolve as a correlated response to evolution of male traits. This implies that, contrary to runaway (Fisherian) models of sexual selection, premating isolation will not arise as an automatic side effect of divergence between populations in sexually selected traits. I evaluate premating isolating mechanisms in one group, the birds. In this group premating isolation is often a consequence of sexual imprinting, whereby young birds learn features of their parents and use these features in mate choice. Song, morphology and plumage are known recognition cues. I conclude that perhaps the main role for sexual selection in speciation is in generating differences between populations in traits. Sexual imprinting then leads to these traits being used as species recognition mechanisms. The second issue addressed in this paper is the role of sexual selection in adaptive radiation, again concentrating on birds. Ecological differences between species include large differences in size, which may in themselves be sufficient for species recognition, and differences in habitat, which seem to evolve frequently and at all stages of an adaptive radiation. Differences in habitat often cause song and plumage patterns to evolve as a result of sexual selection for efficient communication. Therefore sexual selection is likely to have an important role in generating premating isolating mechanisms throughout an adaptive radiation. It is also possible that sexual selection, by creating more allopatric species, creates more opportunity for ecological divergence to occur. The limited available evidence does not support this idea. A role for sexual selection in accelerating ecological diversification has yet to be demonstrated.

Price, T.

1998-01-01

200

Large mainland populations of South Island robins retain greater genetic diversity than offshore island refuges  

Microsoft Academic Search

For conservation purposes islands are considered safe refuges for many species, particularly in regions where introduced predators\\u000a form a major threat to the native fauna, but island populations are also known to possess low levels of genetic diversity.\\u000a The New Zealand archipelago provides an ideal system to compare genetic diversity of large mainland populations where introduced\\u000a predators are common, to

Sanne Boessenkool; Sabrina S. Taylor; Carolyn K. Tepolt; Jan Komdeur; Ian G. Jamieson

2007-01-01

201

Seasonal components of avian population change: Joint analysis of two large-scale monitoring programs  

USGS Publications Warehouse

We present a combined analysis of data from two large-scale surveys of bird populations. The North American Breeding Bird Survey is conducted each summer; the Christmas Bird Count is conducted in early winter. The temporal staggering of these surveys allows investigation of seasonal components of population change, which we illustrate with an examination of the effects of severe winters on the Carolina Wren (Thryothorus ludovicianus). Our analysis uses a hierarchical log-linear model with controls for survey-specific sampling covariates. Temporal change in population size is modeled seasonally, with covariates for winter severity. Overall, the winter?spring seasons are associated with 82% of the total population variation for Carolina Wrens, and an additional day of snow cover during winter?spring is associated with an incremental decline of 1.1% of the population.

Link, W.A.; Sauer, J.R.

2007-01-01

202

Polymorphism in sexual versus non-sexual disease transmission  

E-print Network

Polymorphism in sexual versus non-sexual disease transmission PETER H. THRALL AND JANIS ANTONOVICS transmitted diseases (STDs) often consist of related strains that cause non- sexually transmitted, or `ordinary infectious', diseases (OIDs). We use differential equation models of single populations to derive

Antonovics, Janis

203

Sexually transmitted diseases and travel  

Microsoft Academic Search

Sexually transmitted diseases (STDs) are infections and resulting clinical syndromes caused by more than 25 infectious organisms transmitted through sexual activity. International travellers are at great risk of contracting any of these STDs, including HIV, if they have been sexually exposed to persons with any of these diseases. Population movement has been shown to be a major contributing factor in

Ziad A Memish; Abimbola O Osoba

2003-01-01

204

Sexual Behavior Disorders in Adolescents.  

ERIC Educational Resources Information Center

The paper reviews the literature on sexual delinquency in male and female adolescents and considers guidelines for effective intervention in nonspecialized treatment programs. A section on sexual delinquency in females touches on prostitution and incest, while a section on males notes the changing composition of the sexually delinquent population.…

Erickson, William D.

205

Health benefits of legal services for criminalized populations: the case of people who use drugs, sex workers and sexual and gender minorities.  

PubMed

Social exclusion and legal marginalization are important determinants of health outcomes for people who use illicit drugs, sex workers, and persons who face criminal penalties because of homosexuality or transgenderism. Incarceration may add to the health risks associated with police repression and discrimination for these persons. Access to legal services may be essential to positive health outcomes in these populations. Through concrete examples, this paper explores types of legal problems and legal services linked to health outcomes for drug users, sex workers, and sexual minorities and makes recommendations for donors, legal service providers, and civil society organizations. PMID:21105945

Csete, Joanne; Cohen, Jonathan

2010-01-01

206

Diversity lost: are all Holarctic large mammal species just relict populations?  

PubMed Central

Population genetic analyses of Eurasian wolves published recently in BMC Evolutionary Biology suggest that a major genetic turnover took place in Eurasian wolves after the Pleistocene. These results add to the growing evidence that large mammal species surviving the late Pleistocene extinctions nevertheless lost a large share of their genetic diversity. See research article http://www.biomedcentral.com/1471-2148/10/104 PMID:20409351

2010-01-01

207

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

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. PMID:15204083

Bletzer, Keith V; Koss, Mary P

2004-01-01

208

Sexual dimorphism in a dioecious population of the wind-pollinated herb Mercurialis annua: the interactive effects of resource availability and competition  

PubMed Central

Background and Aims Male-biased sex allocation commonly occurs in wind-pollinated hermaphroditic plants, and is often positively associated with size, notably in terms of height. Currently, it is not well established whether a corresponding pattern holds for dioecious plants: do males of wind-pollinated species exhibit greater reproductive allocation than females? Here, sexual dimorphism is investigated in terms of life history trade-offs in a dioecious population of the wind-pollinated ruderal herb Mercurialis annua. Methods The allocation strategies of males and females grown under different soil nutrient availability and competitive (i.e. no, male or female competitor) regimes were compared. Key Results Male reproductive allocation increased disproportionately with biomass, and was greater than that of females when grown in rich soils. Sexual morphs differentially adjusted their reproductive allocation in response to local environmental conditions. In particular, males reduced their reproductive allocation in poor soils, whereas females increased theirs, especially when competing with another female rather than growing alone. Finally, males displayed smaller above-ground vegetative sizes than females, but neither nutrient availability nor competition had a strong independent effect on relative size disparities between the sexes. Conclusions Selection appears to favour plasticity in reproductive allocation in dioecious M. annua, thereby maintaining a relatively constant size hierarchy between sexual morphs. In common with other dioecious species, there seems to be little divergence in the niches occupied by males and females of M. annua. PMID:21385775

Hesse, Elze; Pannell, John R.

2011-01-01

209

Ecological risk assessment in a large river-reservoir. 6: Bioindicators of fish population health  

Microsoft Academic Search

Spatial distribution of contaminants in the sediments and biota of a large reservoir ecosystem were related to a variety of biological responses in fish populations and communities to determine possible relationships between contaminant loading in the environment and fish health. Much of the contaminant inventory in the Clinch River\\/Watts Bar Reservoir (CR\\/WBR) system has originated from three US Department of

S. Marshall Adams; Mark S. Bevelhimer; Daniel A. Levine; Swee J. Teh

1999-01-01

210

Spatially Regularized Logistic Regression for Disease Mapping on Large Moving Populations  

E-print Network

, or disease mapping, typically relies on information about the residence and health status of individuals from assist in hypothesis generation about disease etiology and allocation of public health resourcesSpatially Regularized Logistic Regression for Disease Mapping on Large Moving Populations Vuk

Vucetic, Slobodan

211

Analysis of fMRI data sampled from Large Populations: Statistical and Methodological Issues  

E-print Network

Analysis of fMRI data sampled from Large Populations: Statistical and Methodological Issues that is present in their datasets across subjects. In particular, this high degree of variability dramatically). Analysing the variability that arises between different datasets is not straightforward, since

Paris-Sud XI, Université de

212

Birth seasonality and calf mortality in a large population of Asian elephants  

E-print Network

Birth seasonality and calf mortality in a large population of Asian elephants Hannah S. Mumby1, Germany Keywords Birth season, climate, conservation, Elephas maximus, offspring mortality, working births on periods with maximum offspring survival prospects remains unknown. We investigated the seasonal

Lummaa, Virpi

213

Global distribution of large lunar craters: implications for resurfacing and impactor populations.  

PubMed

By using high-resolution altimetric measurements of the Moon, we produced a catalog of all impact craters ?20 kilometers in diameter on the lunar surface and analyzed their distribution and population characteristics. The most-densely cratered portion of the highlands reached a state of saturation equilibrium. Large impact events, such as Orientale Basin, locally modified the prebasin crater population to ~2 basin radii from the basin center. Basins such as Imbrium, Orientale, and Nectaris, which are important stratigraphic markers in lunar history, are temporally distinguishable on the basis of crater statistics. The characteristics of pre- and postmare crater populations support the hypothesis that there were two populations of impactors in early solar system history and that the transition occurred near the time of the Orientale Basin event. PMID:20847265

Head, James W; Fassett, Caleb I; Kadish, Seth J; Smith, David E; Zuber, Maria T; Neumann, Gregory A; Mazarico, Erwan

2010-09-17

214

Sexual Abuse Histories of Youth in Child Welfare Residential Treatment Centers: Analysis of the Odyssey Project Population  

ERIC Educational Resources Information Center

This multi-site examination of sexual abuse histories of youth in residential treatment centers asked, for the sample as a whole and by youth's gender: (a) How many perpetrators did each youth have? (b) What was the gender of the perpetrator? (c) What proportion of youth was abused by family members? (d) What proportion of youth was abused in a…

Baker, Amy J. L.; Curtis, Patrick A.; Papa-Lentini, Cynthia

2006-01-01

215

Variation in mating systems and sexual size dimorphism between populations of the Australian python Morelia spilota (Serpentes: Pythonidae)  

Microsoft Academic Search

Although adaptationist hypotheses predict a functional relationship between mating systems and sexual size dimorphism, such predictions are difficult to test because of the high degree of phylogenetic conservatism in both of these traits. Taxa that show intraspecific variation in mating systems hence offer valuable opportunities for more direct tests of evolutionary-ecological hypotheses. Based on a collation of published and unpublished

R. Shine; M. Fitzgerald

1995-01-01

216

Large population solution of the stochastic Luria–Delbrück evolution model  

PubMed Central

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 ?-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. PMID:23818583

Kessler, David A.; Levine, Herbert

2013-01-01

217

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

PubMed

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

Benazzo, Andrea; Panziera, Alex; Bertorelle, Giorgio

2015-01-01

218

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

PubMed Central

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

Benazzo, Andrea; Panziera, Alex; Bertorelle, Giorgio

2015-01-01

219

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

PubMed Central

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. PMID:20882324

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.

2014-01-01

220

Understanding sexual harassment using aggregate construct models.  

PubMed

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). PMID:25265486

Nye, Christopher D; Brummel, Bradley J; Drasgow, Fritz

2014-11-01

221

Acculturation, Health Protective Sexual Communication, and HIV/AIDS Risk Behavior among Hispanic Women in a Large Midwestern City  

ERIC Educational Resources Information Center

The relationships among acculturation, health protective sexual communication, and HIV/AIDS risk behaviors of Hispanic women are examined. Respondents represented 14 Latin American countries, a mean age of 29.5 years, and relatively low education and income levels. A significant correlation was found between higher non-Hispanic acculturation level…

Rojas-Guyler, Liliana; Ellis, Nancy; Sanders, Stephanie

2005-01-01

222

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 ...

223

Physiological characteristics of platelet\\/circulatory serotonin: study on a large human population  

Microsoft Academic Search

The aim of this work was the study of platelet\\/circulatory serotonin (5-hydroxytryptamine, 5-HT), specifically alternative ways of its measurement and main physiological characteristics. The study was performed on a large human population (N=500) of blood donors of both sexes over the course of a longer time period (17 months). Owing to the heterogeneity in measurement of circulatory serotonin encountered in

Branimir Jernej; Miroslav Banovi?; Lipa Cicin-Šain; Dubravka Hranilovi?; Melita Balija; Darko Oreškovi?; Vera Folnegovi?-Šmalc

2000-01-01

224

Montane refugia predict population genetic structure in the Large-blotched Ensatina salamander.  

PubMed

Understanding the biotic consequences of Pleistocene range shifts and fragmentation remains a fundamental goal in historical biogeography and evolutionary biology. Here, we combine species distribution models (SDM) from the present and two late Quaternary time periods with multilocus genetic data (mitochondrial DNA and microsatellites) to evaluate the effect of climate-induced habitat shifts on population genetic structure in the Large-blotched Ensatina (Ensatina eschscholtzii klauberi), a plethodontid salamander endemic to middle and high-elevation conifer forest in the Transverse and Peninsular Ranges of southern California and northern Baja California. A composite SDM representing the range through time predicts two disjunct refugia, one in southern California encompassing the core of the species range and the other in the Sierra San Pedro Mártir of northern Baja California at the southern limit of the species range. Based on our spatial model, we would expect a pattern of high connectivity among populations within the northern refugium and, conversely, a pattern of isolation due to long-term persistence of the Sierra San Pedro Mártir population. Our genetic results are consistent with these predictions based on the hypothetical refugia in that (i) historical measures of population connectivity among stable areas are correlated with gene flow estimates; and (ii) there is strong geographical structure between separate refugia. These results provide evidence for the role of recent climatic change in shaping patterns of population persistence and connectivity within the Transverse and Peninsular Ranges, an evolutionary hotspot. PMID:23379992

Devitt, Thomas J; Devitt, Susan E Cameron; Hollingsworth, Bradford D; McGuire, Jimmy A; Moritz, Craig

2013-03-01

225

Evidence for an Intervening Stellar Population Toward the Large Magellanic Cloud  

NASA Astrophysics Data System (ADS)

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 between the LMC and the Galaxy (although other interpretations, such as debris from the LMC-SMC interaction, are possible). We conclude that the standard assumption of a smoothly distributed halo population out to the LMC cannot be substantiated without at least a detailed understanding of several of the following: red clump stellar evolution, binary fractions, binary mass ratios, the spatial correlation of stars within the LMC, possible variations in the stellar populations of satellite galaxies, and differential reddening - all of which are highly complex.

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

1997-12-01

226

Psychosocial pathways to sexual dysfunction among female inmates.  

PubMed

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. PMID:24496787

Baltieri, Danilo Antonio

2014-08-01

227

Sexual behaviour after antiretroviral therapy initiation in female sex workers and HIV-positive patients from the general population, Cotonou, Benin.  

PubMed

From September 2008 to December 2011, we enrolled and followed-up 247 HIV-negative, 88 untreated and 32 treated HIV-positive female sex workers (FSWs), as well as 238 untreated and 115 treated HIV-positive patients from the general population (GP) of Cotonou, Benin. We wanted to assess the effect of antiretroviral therapy (ART) on sexual risk-taking in FSWs and patients from the GP. We used multivariate log binomial regression models for repeated measures to compare risky behaviours reported during pre-ART and post-ART visits and we performed linear time-trend analyses to assess changes in condom use in all five groups. At 58.8% of pre-ART and 45.3% of post-ART visits (adjusted p-value=0.293), treated FSWs have reported ?16 clients during the last week of work. Inconsistent condom use with clients over the same period decreased by more than 50% (from 20.7 to 10.0%, adjusted p-value=0.082). In treated patients from the GP, inconsistent condom use with regular partners during the last four months was reported at 52.8% of pre-ART and 53.5% of post-ART visits (p=0.778). Reported casual sex was stable (36.8% versus 38.7%, adjusted p-value=0.924). In linear time-trend analyses, there was a significant downward trend in inconsistent condom use at the early stage of the study and stability thereafter in all HIV-negative and HIV-positive FSWs. There was no negative alteration in sexual behaviour following ART initiation either inpatients from the GP or in FSWs. The results underscore the key role of concomitant sexual risk-reduction strategies. PMID:23438011

Diabaté, Souleymane; Chamberland, Annie; Zannou, Djimon M; Geraldo, Nassirou; Azon-Kouanou, Angèle; Massinga-Loembé, Marguérite; Ahomadégbé, Christelle; Labbé, Annie-Claude; Tremblay, Cécile; Alary, Michel

2013-01-01

228

Constraining the Galactic millisecond pulsar population using Fermi Large Area Telescope  

NASA Astrophysics Data System (ADS)

Context. The Fermi Large Area Telescope (Fermi-LAT) has recently revealed a large population of gamma-ray emitting millisecond pulsars (MSPs) in our Galaxy. Aims: We aim to infer the properties of the Galactic population of gamma-ray emitting MSPs from the samples detected by the Fermi-LAT. Methods: We developed a Monte Carlo model to predict the spatial and gamma-ray luminosity distribution of the Galactic MSP population. Based on the estimated detection sensitivity of Fermi-LAT, we split the model population into detectable and undetectable samples of MSPs. Using a maximum likelihood method, we compared the detectable sample to a set of 36 MSPs detected by Fermi-LAT, and we derived the parameters of the spatial distribution and the total number of gamma-ray emitting MSPs in the Galaxy. The corresponding undetectable sample provided us with an estimate for the expected diffuse emission from unresolved MSPs in the Milky Way. We also applied our method to an extended sample of 66 MSPs that combines firmly detected MSPs and ?-ray sources that show characteristics reminiscent of MSPs. Results: Using the sample of 36 MSPs detected by Fermi-LAT, our analysis suggests the existence of 9000-11 000 ?-ray emitting MSPs in the Galaxy. The maximum likelihood analysis suggests an exponential radial scale length of ~4 kpc and an exponential vertical scale height of ~1 kpc for the underlying MSP population. The unresolved population of Galactic ?-ray emitting MSPs is predicted to contribute a flux of ~2 × 10-6 ph cm-2 s-1 sr-1 to the Galactic diffuse emission observed from the central radian above 100 MeV. This value corresponds to ~1% of the total observed ?-ray flux from that region. For latitudes |b| ? 40° the expected average intensity amounts to ~2 × 10-8 ph cm-2 s-1 sr-1 above 100 MeV, which corresponds to 0.2% of the high-latitude background intensity. Using the extended sample increases the estimated number of ?-ray emitting MSPs in the Galaxy to ~22 000 and slightly reduces the scale parameters of the spatial distribution. The results are robust with respect to systematic uncertainties in the estimated Fermi-LAT detection sensitivity. Conclusions: For the first time our analysis provides ?-ray based constraints on the Galactic population of MSPs. The radial scale length and vertical scale height of the population is consistent with estimates based on radio data. Our analysis suggests that MSPs do not provide any significant contribution to the isotropic diffuse ?-ray background emission.

Grégoire, T.; Knödlseder, J.

2013-06-01

229

Multivariate sexual selection in a rapidly evolving speciation phenotype  

PubMed Central

Estimating the fitness surface of rapidly evolving secondary sexual traits can elucidate the origins of sexual isolation and thus speciation. Evidence suggests that sexual selection is highly complex in nature, often acting on multivariate sexual characters that sometimes include non-heritable components of variation, thus presenting a challenge for predicting patterns of sexual trait evolution. Laupala crickets have undergone an explosive species radiation marked by divergence in male courtship song and associated female preferences, yet patterns of sexual selection that might explain this diversification remain unknown. We used female phonotaxis trials to estimate the fitness surface for acoustic characters within one population of Laupala cerasina, a species with marked geographical variation in male song and female preferences. Results suggested significant directional sexual selection on three major song traits, while canonical rotation of the matrix of nonlinear selection coefficients (?) revealed the presence of significant convex (stabilizing) sexual selection along combinations of characters. Analysis of song variation within and among males indicated significantly higher repeatability along the canonical axis of greatest stabilizing selection than along the axis of greatest linear selection. These results are largely consistent with patterns of song divergence that characterize speciation and suggest that different song characters have the potential to indicate distinct information to females during courtship. PMID:23760640

Oh, Kevin P.; Shaw, Kerry L.

2013-01-01

230

Nonprobability Web Surveys to Measure Sexual Behaviors and Attitudes in the General Population: A Comparison With a Probability Sample Interview Survey  

PubMed Central

Background Nonprobability Web surveys using volunteer panels can provide a relatively cheap and quick alternative to traditional health and epidemiological surveys. However, concerns have been raised about their representativeness. Objective The aim was to compare results from different Web panels with a population-based probability sample survey (n=8969 aged 18-44 years) that used computer-assisted self-interview (CASI) for sensitive behaviors, the third British National Survey of Sexual Attitudes and Lifestyles (Natsal-3). Methods Natsal-3 questions were included on 4 nonprobability Web panel surveys (n=2000 to 2099), 2 using basic quotas based on age and sex, and 2 using modified quotas based on additional variables related to key estimates. Results for sociodemographic characteristics were compared with external benchmarks and for sexual behaviors and opinions with Natsal-3. Odds ratios (ORs) were used to express differences between the benchmark data and each survey for each variable of interest. A summary measure of survey performance was the average absolute OR across variables. Another summary measure was the number of key estimates for which the survey differed significantly (at the 5% level) from the benchmarks. Results For sociodemographic variables, the Web surveys were less representative of the general population than Natsal-3. For example, for men, the average absolute OR for Natsal-3 was 1.14, whereas for the Web surveys the average absolute ORs ranged from 1.86 to 2.30. For all Web surveys, approximately two-thirds of the key estimates of sexual behaviors were different from Natsal-3 and the average absolute ORs ranged from 1.32 to 1.98. Differences were appreciable even for questions asked by CASI in Natsal-3. No single Web survey performed consistently better than any other did. Modified quotas slightly improved results for men, but not for women. Conclusions Consistent with studies from other countries on less sensitive topics, volunteer Web panels provided appreciably biased estimates. The differences seen with Natsal-3 CASI questions, where mode effects may be similar, suggest a selection bias in the Web surveys. The use of more complex quotas may lead to some improvement, but many estimates are still likely to differ. Volunteer Web panels are not recommended if accurate prevalence estimates for the general population are a key objective. PMID:25488851

Burkill, Sarah; Couper, Mick P; Conrad, Frederick; Clifton, Soazig; Tanton, Clare; Phelps, Andrew; Datta, Jessica; Mercer, Catherine H; Sonnenberg, Pam; Prah, Philip; Mitchell, Kirstin R; Wellings, Kaye; Johnson, Anne M; Copas, Andrew J

2014-01-01

231

Phylogeography of competing sexual and parthenogenetic forms of a freshwater flatworm: patterns and explanations  

PubMed Central

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:14622447

Pongratz, Norbert; Storhas, Martin; Carranza, Salvador; Michiels, Nicolaas K

2003-01-01

232

Sexual and reproductive health is our business.  

PubMed

The Family Planning Association of Trinidad and Tobago (FPATT) has decided that integration of the concept of sexual and reproductive health into regular family planning activities is the best way to increase the contraceptive prevalence rate. A more holistic approach to service provision is being developed. On the basis of survey findings that early sexual activity, low contraceptive use, and limited knowledge are widespread among young people, this population group has been selected as a focus. FPATT has asked for a TT$1 million subsidy to intensify sex education programs in the schools. Issues discussed include human sexuality, values clarification, relationships, problems affecting teenagers, parenting, rape and incest, and family planning. FPATT also conducts training sessions for teachers and parents. Since young people tend to respond best to peers, peer counseling is emphasized. Education is also offered at large industrial sites, private homes in small communities, and government health centers. PMID:12345375

Sarjeant, H

1993-01-01

233

Stem cells from innate sexual but not acquired sexual planarians have the capability to form a sexual individual.  

PubMed

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. PMID:22968921

Nodono, Hanae; Ishino, Yugo; Hoshi, Motonori; Matsumoto, Midori

2012-11-01

234

Sexual harassment of university faculty by colleagues and students  

Microsoft Academic Search

The focus of this research was on faculty members as victims of sexual harassment by colleagues (peer harassment) and students (contrapower harassment). A self-administered, mailed questionnaire was sent to a probability sample of faculty at a large, public Midwestern university and to the whole population of faculty at a small, public institution in the Western Mountain region. Several hypotheses were

Kathleen McKinney

1990-01-01

235

Reproductive and resource benefits to large female body size in a mammal with female-biased sexual size dimorphism  

SciTech Connect

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.

Fokidis, H.B., T.S. Risch and T.C. Glenn

2007-01-01

236

Sexual Harassment, Sexual Coercion, and HIV Risk Among U.S. Adults 18-49 Years  

Microsoft Academic Search

Sexual harassment and sexual coercion have received considerable public attention. However, the extent of these problems nationally and the breadth of their health consequences are not fully understood. We estimated the national prevalence of sexual harassment and sexual coercion, and examined their relationship to HIV risk in the general U.S. population. Data came from a 1992 telephone survey of a

Kyung-Hee Choi; Diane Binson; Melissa Adelson; Joseph A. Catania

1998-01-01

237

Daphnias: from the individual based model to the large population equation  

E-print Network

The class of deterministic 'Daphnia' models treated by Diekmann et al. (J Math Biol 61: 277-318, 2010) has a long history going back to Nisbet and Gurney (Theor Pop Biol 23: 114-135, 1983) and Diekmann et al. (Nieuw Archief voor Wiskunde 4: 82-109, 1984). In this note, we formulate the individual based models (IBM) supposedly underlying those deterministic models. The models treat the interaction between a general size-structured consumer population ('Daphnia') and an unstructured resource ('algae'). The discrete, size and age-structured Daphnia population changes through births and deaths of its individuals and throught their aging and growth. The birth and death rates depend on the sizes of the individuals and on the concentration of the algae. The latter is supposed to be a continuous variable with a deterministic dynamics that depends on the Daphnia population. In this model setting we prove that when the Daphnia population is large, the stochastic differential equation describing the IBM can be approxima...

Metz, J A J

2012-01-01

238

OIKOS 86: 557-565. Copenhagen1999 Population cycles in small mammals: the role of age at sexual  

E-print Network

(age at maturity, fertility, juvenile survival and adult survival) on population cycles. Our, Boonstra 1994,Krebs 1996). In the low-density, in- creasingphase,age at maturity decreases,juvenile sur of popula- tions. In high-density, declining populations, age at maturity is delayed,juvenile survival

Oli, Madan K.

239

IMPACT OF MATE AVAILABILITY, POPULATION SIZE, AND SPATIAL AGGREGATION OF MORPHS ON SEXUAL REPRODUCTION IN A DISTYLOUS, AQUATIC PLANT1  

Microsoft Academic Search

In distylous, self-incompatible plants, clonal propagation, unbalanced floral morph frequencies, and reduced population size can interfere with the functioning of distyly by compromising legitimate intermorph pollinations, resulting in reduced reproductive output. Here, we examined the mating system and the impact of mate availability, population size, and spatial aggregation of morphs on reproductive output in the distylous, clonal, aquatic plant Hottonia

REIN BRYS; HANS JACQUEMYN; MARTIN HERMY

2007-01-01

240

RESOURCES FOR VICTIMS OF SEXUAL ASSAULT Bronx District Attorney's Office  

E-print Network

evenings Populations served: Survivors of rape / sexual assault, sexual harassment, and adults sexually-Mail: elaine.garbaty@nbhn.net Hours: M-F 9-5 ER24/7 Populations served: Survivors of rape / sexual assault a week coverage in the Emergency Department. Social workers available 9-5 PM and rape crisis counselors

Rosen, Jay

241

Evolutionary potential of a large marine vertebrate: quantitative genetic parameters in a wild population.  

PubMed

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. PMID:19236474

Dibattista, Joseph D; Feldheim, Kevin A; Garant, Dany; Gruber, Samuel H; Hendry, Andrew P

2009-04-01

242

Behavioral Convergence: Implications for Mathematical Models of Sexually Transmitted Infection Transmission  

PubMed Central

Recent trends in the behaviors of some groups with high sexual activity and of the general population in some countries suggest that sexual behavior profiles of high and low sexual activity categories may be converging and may call into question the assumptions around sexual mixing that are built into theoretical models of sexually transmitted infections (STIs)/human immunodeficiency virus (HIV) transmission dynamics. One category of high sexual activity, sex work, has been undergoing modification in many societies, becoming more acceptable, more dispersed, and larger in volume in some societies and shrinking in others. Concurrent with changes in the characteristics of sex work, the accumulating data on the sexual behaviors of the general population suggest a shift toward those of sex workers, including large numbers of sex partners and short-duration partnerships. The closing of the gap between behaviors associated with high and low sexual activity may have important implications for theories of sexual structure and models of transmission dynamics for STIs, including HIV infection. PMID:25381381

Aral, Sevgi O.; Ward, Helen

2014-01-01

243

Behavioral convergence: implications for mathematical models of sexually transmitted infection transmission.  

PubMed

Recent trends in the behaviors of some groups with high sexual activity and of the general population in some countries suggest that sexual behavior profiles of high and low sexual activity categories may be converging and may call into question the assumptions around sexual mixing that are built into theoretical models of sexually transmitted infections (STIs)/human immunodeficiency virus (HIV) transmission dynamics. One category of high sexual activity, sex work, has been undergoing modification in many societies, becoming more acceptable, more dispersed, and larger in volume in some societies and shrinking in others. Concurrent with changes in the characteristics of sex work, the accumulating data on the sexual behaviors of the general population suggest a shift toward those of sex workers, including large numbers of sex partners and short-duration partnerships. The closing of the gap between behaviors associated with high and low sexual activity may have important implications for theories of sexual structure and models of transmission dynamics for STIs, including HIV infection. PMID:25381381

Aral, Sevgi O; Ward, Helen

2014-12-01

244

Sexual coercion and the misperception of sexual intent?  

PubMed Central

Misperceiving a woman’s platonic interest as sexual interest has been implicated in a sexual bargaining process that leads to sexual coercion. This paper provides a comprehensive review of sexual misperception, including gender differences in perception of women’s sexual intent, the relationship between sexual coercion and misperception, and situational factors that increase the risk that sexual misperception will occur. Compared to women, men consistently perceive a greater degree of sexual intent in women’s behavior. However, there is evidence to suggest that this gender effect may be driven largely by a sub-group of men who are particularly prone to perceive sexual intent in women’s behavior, such as sexually coercive men and men who endorse sex-role stereotypes. Situational factors, such as alcohol use by the man or woman, provocative clothing, and dating behaviors (e.g., initiating the date or making eye contact), are all associated with increased estimates of women’s sexual interest. We also critique the current measurement strategies and introduce a model of perception that more closely maps on to important theoretical questions in this area. A clearer understanding of sexual perception errors and the etiology of these errors may serve to guide sexual-assault prevention programs toward more effective strategies. PMID:17462798

Farris, Coreen; Treat, Teresa A.; Viken, Richard J.; McFall, Richard M.

2010-01-01

245

Sexual coercion and the misperception of sexual intent.  

PubMed

Misperceiving a woman's platonic interest as sexual interest has been implicated in a sexual bargaining process that leads to sexual coercion. This paper provides a comprehensive review of sexual misperception, including gender differences in perception of women's sexual intent, the relationship between sexual coercion and misperception, and situational factors that increase the risk that sexual misperception will occur. Compared to women, men consistently perceive a greater degree of sexual intent in women's behavior. However, there is evidence to suggest that this gender effect may be driven largely by a sub-group of men who are particularly prone to perceive sexual intent in women's behavior, such as sexually coercive men and men who endorse sex-role stereotypes. Situational factors, such as alcohol use by the man or woman, provocative clothing, and dating behaviors (e.g., initiating the date or making eye contact), are all associated with increased estimates of women's sexual interest. We also critique the current measurement strategies and introduce a model of perception that more closely maps on to important theoretical questions in this area. A clearer understanding of sexual perception errors and the etiology of these errors may serve to guide sexual-assault prevention programs toward more effective strategies. PMID:17462798

Farris, Coreen; Treat, Teresa A; Viken, Richard J; McFall, Richard M

2008-01-01

246

Internet Sexualities  

Microsoft Academic Search

\\u000a The term “internet sexuality” (or OSA, online sexual activities) refers to sexual-related content and activities observable\\u000a on the internet (cf. Adams, Oye, & Parker, 2003; Cooper, McLoughlin, & Campbell, 2000; Leiblum & Döring, 2002). It designates\\u000a a variety of sexual phenomena (e.g., pornography, sex education, sexual contacts) related to a wide spectrum of online services\\u000a and applications (e.g., websites, online

Nicola Döring

2010-01-01

247

A Connectionist Modeling Approach to Rapid Analysis of Emergent Social Cognition Properties in Large-Populations  

SciTech Connect

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.

Perumalla, Kalyan S [ORNL; Schryver, Jack C [ORNL

2009-01-01

248

Foraging costs of a tail ornament: Experimental evidence from two populations of barn swallows Hirundo rustica with different degrees of sexual size dimorphism  

Microsoft Academic Search

Secondary sexual characters are assumed to be costly to produce or maintain. A test of this assumption was performed using the sexually exaggerated outermost tail feathers of male barn swallows Hirundo rustica, a trait currently subject of a directional female mate preference. A possible cost of sexual signalling in male barn swallows arises from increased flight cost during foraging in

A. P. Moller; F. Lope; J. M. López Caballero

1995-01-01

249

Large Magellanic Cloud Planetary Nebula Morphology: Probing Stellar Populations and Evolution.  

PubMed

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. PMID:10813674

Stanghellini; Shaw; Balick; Blades

2000-05-10

250

Individual quality, early-life conditions, and reproductive success in contrasted populations of large herbivores.  

PubMed

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. PMID:19694145

Hamel, Sandra; Gaillard, Jean-Michel; Festa-Bianchet, Marco; Côté, Steeve D

2009-07-01

251

Crassicaudosis: a parasitic disease threatening the health and population recovery of large baleen whales.  

PubMed

This communication briefly reviews knowledge of the systemic disease caused by Crassicauda boopis in blue whales (Balaenoptera musculus), fin whales (B. physalus) and humpback whales (Megaptera novaeangliae). Infections with this giant nematode characteristically incite a chronic inflammatory reaction of the blood vessels which drain the kidneys. In this critical location, the parasite-induced lesion can cause complete vascular occlusion and kidney failure. Whale calves and juveniles typically suffer the heaviest parasite burdens following transplacental infection of the developing whale foetus. There is also probable whale-to-whale transmission post-partum, involving urinary contamination of the environment with C. boopis eggs and larvae. The frequency of the infection can exceed 95%. Haematological findings suggest that systemic pathological effects are typical at the population level. Gradual development of occlusive lesions in the renal veins appears to correlate with a major peak in natural mortality at about one year of age. To date, all findings support the conclusion that premature death caused by C. boopis infection is potentially a major impediment to population recovery of affected whale species. This suggests the interesting possibility of actively encouraging the population recovery of three species of large baleen whales. Such a restoration effort would entail remotely-deployed anthelminthic therapy administered, at sea, to infected whale cows and calves. PMID:1305859

Lambertsen, R H

1992-12-01

252

Population Genetics of Two Asexually and Sexually Reproducing Psocids Species Inferred by the Analysis of Mitochondrial and Nuclear DNA Sequences  

PubMed Central

Background The psocids Liposcelis bostrychophila and L. entomophila (Psocoptera: Liposcelididae) are found throughout the world and are often associated with humans, food stores and habitations. These insects have developed high levels of resistance to various insecticides in grain storage systems. However, the population genetic structure and gene flow of psocids has not been well categorized, which is helpful to plan appropriate strategies for the control of these pests. Methodology/Principal Findings The two species were sampled from 15 localities in China and analyzed for polymorphisms at the mitochondrial DNA (Cytb) and ITS (ITS1-5.8S-ITS2) regions. In total, 177 individual L. bostrychophila and 272 individual L. entomophila were analysed. Both Cytb and ITS sequences showed high genetic diversity for the two species with haplotype diversities ranged from 0.154±0.126 to 1.000±0.045, and significant population differentiation (mean FST?=?0.358 for L. bostrychophila; mean FST?=?0.336 for L. entomophila) was also detected among populations investigated. A Mantel test indicated that for both species there was no evidence for isolation-by-distance (IBD). The neutrality test and mismatch distribution statistics revealed that the two species might have undergone population expansions in the past. Conclusion Both L. bostrychophila and L. entomophila displayed high genetic diversity and widespread population genetic differentiation within and between populations. The significant population differentiation detected for both psocids may be mainly due to other factors, such as genetic drift, inbreeding or control practices, and less by geographic distance since an IBD effect was not found. PMID:22479465

Wei, Dan-Dan; Yuan, Ming-Long; Wang, Bao-Jun; Zhou, An-Wei; Dou, Wei; Wang, Jin-Jun

2012-01-01

253

Sexuality in nursing homes: practice and policy.  

PubMed

Older adults' sexuality and sexual expression are often overlooked in nursing home and residential care settings. Despite cultural beliefs that this population is asexual, sexual activity occurs frequently among residents in long-term care. This study, using written survey instrumentation, examines the scope of resident sexuality, staff reactions to sexual behavior, and the policies and guidelines used in 91 nursing homes to address residents' sexual activity. Eighty-five percent of respondents reported that sexual activity had occurred in their homes, and staff reactions to sexual activity were based on general guidelines. Many responses indicated that sexual expression of residents was considered non-normative. Issues of consent, especially concerning residents with dementia, and residents' right to privacy were addressed using existing general policies. Survey results demonstrate a need for specific policies and staff training regarding sexual expression to be developed with the input of nurses, family members, and residents. PMID:23614386

Doll, Gayle M

2013-07-01

254

Characterization of mitochondrial haplogroups in a large population-based sample from the United States.  

PubMed

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. PMID:24488180

Mitchell, Sabrina L; Goodloe, Robert; Brown-Gentry, Kristin; Pendergrass, Sarah A; Murdock, Deborah G; Crawford, Dana C

2014-07-01

255

Impact of mate availability, population size, and spatial aggregation of morphs on sexual reproduction in a distylous, aquatic plant.  

PubMed

In distylous, self-incompatible plants, clonal propagation, unbalanced floral morph frequencies, and reduced population size can interfere with the functioning of distyly by compromising legitimate intermorph pollinations, resulting in reduced reproductive output. Here, we examined the mating system and the impact of mate availability, population size, and spatial aggregation of morphs on reproductive output in the distylous, clonal, aquatic plant Hottonia palustris. Controlled pollinations under greenhouse conditions detected no spontaneous selfing without the action of a pollen vector (autonomous autogamy) and demonstrated very low fruit and seed development after self-pollination. Intermorph (legitimate) crossings resulted in high reproductive output in both floral morphs (long- and short-styled individuals), whereas intramorph (illegitimate) crossings decreased fruit and seed development by more than 50%, indicating that the species has partial intramorph-incompatibility. In natural populations, small population size and increasing deviation of floral morph frequencies negatively affected reproductive outcome. Individuals of the majority morph type developed significantly fewer fruit and seeds than individuals of the minority morph type. This rapid decline in fecundity was symmetrical, indicating that regardless of which morph was in the majority, the same patterns of negative frequency-dependent mating occurred. Increasing spatial isolation between compatible morphs significantly reduced fruit and seed set in both morphs similarly. This study provides clear indications of frequency- and context-dependent mating in natural populations of a distylous plant species. PMID:21642214

Brys, Rein; Jacquemyn, Hans; Hermy, Martin

2007-01-01

256

Aging and sexuality.  

PubMed Central

Recent research suggesting that a high proportion of men and women remain sexually active well into later life refutes the prevailing myth that aging and sexual dysfunction are inexorably linked. Age-related physiological changes do not render a meaningful sexual relationship impossible or even necessarily difficult. In men, greater physical stimulation is required to attain and maintain erections, and orgasms are less intense. In women, menopause terminates fertility and produces changes stemming from estrogen deficiency. The extent to which aging affects sexual function depends largely on psychological, pharmacological, and illness-related factors. In this article I review the physiological sex-related changes that occur as part of the normal aging process in men and women. I also summarize the effects on sexual function of age-related psychological issues, illness factors, and medication use. An understanding of the sexual changes that accompany normal aging may help physicians give patients realistic and encouraging advice on sexuality. Although it is important that older men and women not fall into the psychosocial trap of expecting (or worse, trying to force) the kind and degree of sexual response characteristic of their youth, it is equally as important that they not fall prey to the negative folklore according to which decreased physical intimacy is an inevitable consequence of the passage of time. PMID:9348761

Meston, C M

1997-01-01

257

Sexual Health Interventions: A Meta-Analysis.  

PubMed

In the second of two companion papers, we conducted a meta-analysis of sexual health interventions in three domains. The interventions chosen for the meta-analysis were a subset of studies presented in a narrative review (the first of the two companion papers); these in turn were selected on the basis of fit to principles derived from the World Health Organization (WHO) and other definitions of sexual health. Studies (n = 20) were drawn from Medline and PsycINFO databases (English language, adult populations, 1996-2011) and fell into three domains: knowledge, attitudes, and sexual behaviors. We estimated intervention effects via Hedges' g, using the random-effects approach. Initial estimates revealed a large effect for knowledge, g = 1.32 (95% CI = 0.51-2.14), and smaller effects for attitude change, g = 0.17 (0.11-0.24) and behavior, g = 0.21 (0.13-0.29). After removing outliers to produce more precise estimates, the final effect sizes for knowledge, attitudes, and sexual behavior were, respectively, 0.25 (0.03-0.48), 0.18 (0.12-0.24), and 0.18 (0.11-0.24). Interventions yielded positive effects across populations and in all the domains studied. PMID:25211119

Becasen, Jeffrey S; Ford, Jessie; Hogben, Matthew

2014-09-11

258

Predicted Exposures to Steroid Estrogens in U.K. Rivers Correlate with Widespread Sexual Disruption in Wild Fish Populations  

Microsoft Academic Search

Steroidal estrogens, originating principally from human excretion, are likely to play a major role in causing widespread endocrine disruption in wild populations of the roach (Rutilus rutilus), a com- mon cyprinid fish, in rivers contaminated by treated sewage effluents. Given the extent of this problem, risk assessment models are needed to predict the location and severity of endocrine dis- ruption

Susan Jobling; Richard Williams; Andrew Johnson; Ayesha Taylor; Melanie Gross-Sorokin; Monique Nolan; Charles R. Tyler; Ronny van Aerle; Eduarda Santos; Geoff Brighty

2005-01-01

259

Atrial fibrillation in a multiethnic inpatient population of a large public hospital.  

PubMed Central

INTRODUCTION: Atrial fibrillation (AF) has not been well-studied in minority and underserved populations. We report a one-year inpatient experience of AF among 80,021 total ECG records in a multiethnic population of a large public hospital. METHODS: ECG parameters, demographic data, discharge diagnoses, and discharge status were compiled for the first 1,999 hospitalizations associated with AF among 80,021 total ECG records and compared among the population subgroups. RESULTS: Of 3,935 records of patients with AF, 737 matched first hospitalizations. Mean age was 62.3 years; 56% were male. Hispanics comprised 59.2%, Caucasians 16.4%, Asians 11.1%, African Americans 10.3%; unclassified 3%; 30.6% were uninsured. Compared to Caucasians, Left ventricular hypertrophy was more common in African-American [9.9% vs. 21.1%, odds ratio (OR)=2.3] and Asians (9.9% vs. 15.3%, OR=2.76). At discharge, Caucasians more frequently had coronary artery disease, compared to Hispanics (26.4% vs. 17.7%, OR=0.62), African Americans (26.4% vs. 10.5%, OR=0.36), and Asians (26.4% vs. 8.5%, OR=0.25); cardiomyopathy was less common in Caucasians as compared to African Americans (2.5% vs. 10.5%, OR=4.2), Hispanics (2.5% vs. 3.9%, OR=1.5) and Asians (2.5% vs. 4.9%, OR=1.96). Mortality was 16%; nonsurvivors compared to survivors were older, 64.9 years vs. 61.8 years, p<0.05, more frequently had myocardial infarction (20.4% vs. 6.2%, p=0.000) and stroke (16.5% vs. 5.0%, p=0.000). CONCLUSIONS: This AF population, particularly African Americans, was younger than previously reported. ECG and discharge parameters had differential frequencies among race/ethnic subgroups. Nonsurvivors were older and more commonly had myocardial infarction and stroke. Further study is warranted of AF occurrence, management, and outcomes in lower-socioeconomic, multiethnic populations. Images Figure 2 PMID:15586647

Dang, David; Patel, Rajan; Haywood, L. Julian

2004-01-01

260

Populations  

NSDL National Science Digital Library

This chapter introduces population as a group of the same kind of organisms in a given space at a given time. The activities in this section will provide students with the opportunity to define population, estimate populations in a community, and count and compare populations within a community. Students will gain the knowledge in describing plant and animal populations living in a community. They will also experiment with plant populations to control growth and development, not to mention discuss the effects of abiotic conditions on a community.

Galle, Janet R.; Warren, Patricia A.

2005-01-01

261

Sexual Difficulties  

MedlinePLUS

... difficulties Explore other publications and websites Age Page: Sexuality in Later Life - This brochure describes the normal ... effects of illness, disability, and emotional concerns of sexuality in later life. Atrophic Vaginitis (Copyright © UCLA Health ...

262

Healthy Sexuality  

MedlinePLUS Videos and Cool Tools

... a sexual experience is safe, healthy, and enjoyable. Sexual health is a vital part of a person’s total well-being. Of course, sex is essential for reproduction, but it can also build intimacy in relationships ...

263

Sexual Abuse  

MedlinePLUS

... between victim and suspect Inappropriate, unusual, or aggressive sexual behavior How can I learn more? "Speaking the unspeakable: An interview about elder sexual assault with Holly Ramsey-Klawsnik, Ph.D" in ...

264

Mass-loss From Evolved Stellar Populations In The Large Magellanic Cloud  

NASA Astrophysics Data System (ADS)

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.

Riebel, David

2012-01-01

265

Sexual conflict  

Microsoft Academic Search

Sexual conflict occurs when the genetic interests of males and females diverge. Recent evidence supporting the view that male and female genomes are in conflict has now revolutionized the way in which we interpret interactions between the sexes, and suggests that sexual conflict is a potent force in male–female coevolution. Here, we consider the nature of sexual conflict and what

Tracey Chapman; Göran Arnqvist; Jenny Bangham; Locke Rowe

2003-01-01

266

Population.  

ERIC Educational Resources Information Center

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…

King, Pat; Landahl, John

267

Mental health of victims of sexual violence in eastern Congo: associations with daily stressors, stigma, and labeling  

PubMed Central

Background The conflict-ridden context of eastern Congo has set the scene for grueling human rights violations, with sexual violence as one of the ‘weapons of war’. Currently, sexual violence continues, with a considerable increase in civilian perpetrators. However, little is known regarding the particular impact of different experiences of sexual violence on adolescents’ mental health. This study therefore investigates the impact of sexual violence on eastern Congolese adolescents’ mental health and its differing associations with daily stressors, stigma, and the labeling of sexual violence (as ‘rape’ or ‘non-consensual sexual experience’). Methods A cross-sectional, population-based survey design was implemented in 22 secondary schools, randomly selected from a stratified sample, in Bunia, eastern Congo, a region extensively affected by war. A total of 1,305 school-going adolescent girls aged 11 to 23 participated. Self-report measures of mental health symptoms, war-related traumatic events, experiences of sexual violence, daily stressors, and stigmatization were administered. Differences in sociodemographic characteristics, traumatic experiences and daily and social stressors between types of sexual violence (rape, non-consensual sexual violence, no sexual violence) were explored through statistical analysis. ANCOVA analyses investigated associations between those risk factors and adolescents’ mental health. Results More than one third of eastern Congolese adolescent girls reported experiences of sexual violence. Elevated levels of daily stressors, experiences of stigmatization, and stressful war-related events were found amongst girl victims of sexual violence, with the highest levels for girls who labeled the sexual violence as rape. Daily stressors, stigmatization, and war-related events showed a large impact on the girls’ mental health. Last, girls who labeled the sexual violence as non-consensual sexual experiences reported more post-traumatic hyper-arousal and intrusion symptoms compared to those labeling the sexual violence as rape. Conclusions These findings point to the important association between how war-affected adolescent girls label sexual violence (rape or non-consensual sexual experiences) and their mental health. This study also documents the large impact of sexual violence on other stressors (daily stressors, stigmatization, and stressful war events) and the impact of these stressors on girl victims’ mental health. It discusses important implications for addressing sexual violence and its consequences in war-affected contexts. PMID:25195041

2014-01-01

268

A POPULATION OF ACCRETED SMALL MAGELLANIC CLOUD STARS IN THE LARGE MAGELLANIC CLOUD  

SciTech Connect

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.

Olsen, Knut A. G.; Blum, Robert D. [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States); Zaritsky, Dennis [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Boyer, Martha L.; Gordon, Karl D., E-mail: kolsen@noao.edu, E-mail: rblum@noao.edu, E-mail: dzaritsky@as.arizona.edu, E-mail: mboyer@stsci.edu, E-mail: kgordon@stsci.edu [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

2011-08-10

269

Constraints on the Galactic Population of TEV Pulsar Wind Nebulae Using Fermi Large Area Telescope Observations  

E-print Network

Pulsar wind nebulae (PWNe) have been established as the most populous class of TeV gamma-ray emitters. Since launch, the Fermi Large Area Telescope (LAT)identified five high-energy (100MeV large number of PWNe candidates, all powered by young and energetic pulsars. The wealth of multi-wavelength data available and the new results provided by Fermi-LAT give us an opportunity to find new PWNe and to explore the radiative processes taking place in known ones. The TeV gamma-ray unidentifiedsources (UNIDs) are the best candidates for finding new PWNe. Using 45 months of Fermi-LAT data for energies above 10 GeV, an analysis was performed near the position of 58TeV PWNe and UNIDs within 5deg of the Galactic Plane to establish new constraints on PWNe properties and find new clues on the nature of UNIDs. Of the 58 sources, 30 were detected, and this work provides their gamma-rayfluxes for energies above 10 GeV. The spectral energy distributions (SED) anduppe...

Acero, F; Ajello, M; Allafort, A; Baldini, L; Ballet, J; Barbiellini, G; Bastieri, D; Bechtol, K; Bellazzini, R; Blandford, R D; Bloom, E D; Bonamente, E; Bottacini, E; Brandt, T J; Bregeon, J; Brigida, M; Bruel, P; Buehler, R; Buson, S; Caliandro, G A; Cameron, R A; Caraveo, P A; Cecchi, C; Charles, E; Chaves, R C G; Chekhtman, A; Chiang, J; Chiaro, G; Ciprini, S; Claus, R; Cohen-Tanugi, J; Conrad, J; Cutini, S; Dalton, M; D'Ammando, F; de Palma, F; Dermer, C D; Di Venere, L; Silva, E do Couto e; Drell, P S; Drlica-Wagner, A; Falletti, L; Favuzzi, C; Fegan, S J; Ferrara, E C; Focke, W B; Franckowiak, A; Fukazawa, Y; Funk, S; Fusco, P; Gargano, F; Gasparrini, D; Giglietto, N; Giordano, F; Giroletti, M; Glanzman, T; Godfrey, G; Grégoire, T; Grenier, I A; Grondin, M -H; Grove, J E; Guiriec, S; Hadasch, D; Hanabata, Y; Harding, A K; Hayashida, M; Hayashi, K; Hays, E; Hewitt, J; Hill, A B; Horan, D; Hou, X; Hughes, R E; Inoue, Y; Jackson, M S; Jogler, T; Jóhannesson, G; Johnson, A S; Kamae, T; Kawano, T; Kerr, M; Knödlseder, J; Kuss, M; Lande, J; Larsson, S; Latronico, L; Lemoine-Goumard, M; Longo, F; Loparco, F; Lovellette, M N; Lubrano, P; Marelli, M; Massaro, F; Mayer, M; Mazziotta, M N; McEnery, J E; Mehault, J; Michelson, P F; Mitthumsiri, W; Mizuno, T; Monte, C; Monzani, M E; Morselli, A; Moskalenko, I V; Murgia, S; Nakamori, T; Nemmen, R; Nuss, E; Ohsugi, T; Okumura, A; Orienti, M; Orlando, E; Ormes, J F; Paneque, D; Panetta, J H; Perkins, J S; Pesce-Rollins, M; Piron, F; Pivato, G; Porter, T A; Rainò, S; Rando, R; Razzano, M; Reimer, A; Reimer, O; Reposeur, T; Ritz, S; Roth, M; Rousseau, R; Parkinson, P M Saz; Schulz, A; Sgrò, C; Siskind, E J; Smith, D A; Spandre, G; Spinelli, P; Suson, D J; Takahashi, H; Takeuchi, Y; Thayer, J G; Thayer, J B; Thompson, D J; Tibaldo, L; Tibolla, O; Tinivella, M; Torres, D F; Tosti, G; Troja, E; Uchiyama, Y; Vandenbroucke, J; Vasileiou, V; Vianello, G; Vitale, V; Werner, M; Winer, B L; Wood, K S; Yang, Z

2013-01-01

270

Immunization with adenovirus at the large intestinal mucosa as an effective vaccination strategy against sexually transmitted viral infection  

Microsoft Academic Search

The large intestinal mucosa contains immunological structures that may potentially serve as a site for induction of mucosal immunity against infections. Adenovirus (Ad), which is effective in gene transfer to epithelia, may be an ideal antigen delivery system for vaccination at the large intestinal mucosa. To investigate this potential, we immunized mice with recombinant replication-deficient Ad through a single intracolorectal

Q Zhu; C W Thomson; K L Rosenthal; M R McDermott; S M Collins; J Gauldie

2008-01-01

271

Effects of subjective sexual arousal on sexual, pathogen, and moral disgust sensitivity in women and men.  

PubMed

The present experiment tested a novel method of manipulating subjective sexual arousal to examine the effects of sexual arousal on disgust sensitivity. Participants were instructed to employ their own preferred methods of achieving sexual or physiological arousal in the privacy of their own home to reach a target state of arousal. Participants then completed the Three-Domain Disgust Scale (Tybur, Lieberman, & Griskevicius, 2009), which measures sensitivity to sexual, pathogen, and moral disgust. The sexual arousal manipulation caused large, homogenous increases in sexual arousal in women and men. In women, sexual arousal (but not physiological arousal) significantly reduced sensitivity to sexual disgust and marginally increased sensitivity to pathogen disgust. In men, sexual arousal did not decrease disgust sensitivity in any domain. Findings support the evolutionary hypothesis that sexual arousal inhibits sexual disgust, which facilitates an organism's willingness to engage in high-risk, but evolutionarily necessary, reproductive behaviors, an effect that could be particularly important for women. PMID:24595916

Lee, Ellen M; Ambler, James K; Sagarin, Brad J

2014-08-01

272

Hormone Replacement Therapy, Oral Contraceptive Use, and Distal Large Bowel Cancer: A Population-Based Case–Control Study  

Microsoft Academic Search

OBJECTIVES:Lower incidence rates of distal large bowel cancer in women when compared with men support the protective role of female hormones. We aimed to determine the associations between hormone replacement therapy, oral contraceptive use, and distal large bowel cancer.METHODS:We conducted a population-based case–control study of incident distal large bowel cancer in North Carolina between 2001 and 2006. Data on hormone

Millie D Long; Christopher F Martin; Joseph A Galanko; Robert S Sandler

2010-01-01

273

Stellar Populations in Three Outer Fields of the Large Magellanic Cloud  

NASA Astrophysics Data System (ADS)

We present Hubble Space Telescope photometry for three fields in the outer disk of the Large Magellanic Cloud (LMC) extending approximately 4 mag below the faintest main-sequence turnoff. We cannot detect any strongly significant differences in the stellar populations of the three fields based on the morphologies of the color-magnitude diagrams, the luminosity functions, and the relative numbers of stars in different evolutionary stages. Our observations therefore suggest similar star formation histories in these regions, although some variations are certainly allowed. The fields are located in two regions of the LMC: one is in the northeast and two are located in the northwest. Under the assumption of a common star formation history, we combine the three fields with ground-based data at the same location as one of the fields to improve statistics for the brightest stars. We compare this stellar population with those predicted from several simple star formation histories suggested in the literature, using a combination of the R-method of Bertelli et al. (1992) and comparisons with the observed luminosity function. The only model we consider that is not rejected by the observations is one in which the star formation rate is roughly constant for most of the LMC's history and then increases by a factor of 3 about 2 Gyr ago. Such a model has roughly equal numbers of stars older and younger than 4 Gyr, and thus is not dominated by young stars. This star formation history, combined with a closed-box chemical evolution model, is consistent with observations that the metallicity of the LMC has doubled in the past 2 Gyr. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.

Geha, Marla C.; Holtzman, Jon A.; Mould, Jeremy R.; Gallagher, John S., III; Watson, Alan M.; Cole, Andrew A.; Grillmair, Carl J.; Stapelfeldt, Karl R.; Ballester, Gilda E.; Burrows, Christopher J.; Clarke, John T.; Crisp, David; Evans, Robin W.; Griffiths, Richard E.; Hester, J. Jeff; Scowen, Paul A.; Trauger, John T.; Westphal, James A.

1998-03-01

274

Effects of a large northern European no-take zone on flatfish populations.  

PubMed

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. PMID:24090556

Florin, A-B; Bergström, U; Ustups, D; Lundström, K; Jonsson, P R

2013-10-01

275

Characteristics of Resistant Hypertension in a Large Ethnically Diverse Hypertension Population of an Integrated Health System  

PubMed Central

Objective To evaluate the prevalence and characterize resistant hypertension from a large representative population with successful hypertension management and reliable health information. Patient and Methods We performed a cross sectional study using clinical encounter, laboratory, and administrative information from the Kaiser Permanente Southern California health system during 1/1/2006–12/31/2007. From individuals age >17 years with hypertension, resistant hypertension was identified and prevalence determined. Multivariable logistic regression was used to calculate odds ratios (OR) with adjustments for demographics, clinical variables, and medication use. Results Among 470,386 hypertensive individuals, 12.8% were identified as resistant representing15.3% of those on medications. Overall, 37,061 (7.9%) had uncontrolled hypertension while on ? 3 medicines. OR (95% confidence interval) for resistant hypertension were greater for black race (1.68, 1.62–1.75), older age (1.11, 1.10–1.11 for every 5 year increase), males (1.06, 1.03–1.10), and obesity (1.46, 1.42–1.51). Medication adherence rates were higher in resistant hypertension (93 vs 90%, p<0.001). Chronic kidney disease (1.84, 1.78–1.90), diabetes (1.58, 1.53–1.63), and cardiovascular disease (1.34, 1.30–1.39) were also associated with higher risk for resistant hypertension. Conclusion Within a more standardized hypertension treatment environment, we observed a rate of resistant hypertension comparable to past studies using more fragmented data sources. Past observations have been limited due to non-representative populations, reliability of the data, heterogeneity of the treatment environments, and less than ideal control rates. This cohort which was established with an electronic medical record based approach has the potential to provide a better understanding of resistant hypertension and outcomes. PMID:24079679

Sim, John J.; Bhandari, Simran K.; Shi, Jiaxiao; In Liu, Lu A.; Calhoun, David A.; McGlynn, Elizabeth A.; Kalantar-Zadeh, Kamyar; Jacobsen, Steven J.

2013-01-01

276

Effective Strategies to Overcome the Barriers of Poverty in Large Comprehensive High Schools with a Large Minority and Severely Economically Disadvantaged Population  

ERIC Educational Resources Information Center

Purpose: The purpose of this study was to identify effective strategies used by principals of high-poverty, large high schools with more than 70% minority student population, that overcome the barriers identified for high poverty in the literature. Methodology: Descriptive research was used to gather qualitative and quantitative data to identify…

Sheffield, Lynne M.

2012-01-01

277

Population.  

ERIC Educational Resources Information Center

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

International Planned Parenthood Federation, London (England).

278

Prevalence of Sexual Dysfunctions  

PubMed Central

Ten years of research that has provided data regarding the prevalence of sexual dysfunctions is reviewed. A thorough review of the literature identified 52 studies that have been published in the 10 years since an earlier review by Spector and Carey (1990). Community samples indicate a current prevalence of 0 - 3% for male orgasmic disorder, 0 - 5% for erectile disorder, and 0 - 3% for male hypoactive sexual desire disorder. Pooling current and 1-year figures provides community prevalence estimates of 7 - 10% for female orgasmic disorder and 4 - 5% for premature ejaculation. Stable community estimates of the current prevalence for the other sexual dysfunctions remain unavailable. Prevalence estimates obtained from primary care and sexuality clinic samples are characteristically higher. Although a relatively large number of studies have been conducted since Spector and Carey’s (1990) review, the lack of methodological rigor of many studies limits the confidence that can be placed in these findings. PMID:11329727

Simons, Jeffrey; Carey, Michael P.

2008-01-01

279

Sleep and use of electronic devices in adolescence: results from a large population-based study  

PubMed Central

Objectives Adolescents spend increasingly more time on electronic devices, and sleep deficiency rising in adolescents constitutes a major public health concern. The aim of the present study was to investigate daytime screen use and use of electronic devices before bedtime in relation to sleep. Design A large cross-sectional population-based survey study from 2012, the youth@hordaland study, in Hordaland County in Norway. Setting Cross-sectional general community-based study. Participants 9846 adolescents from three age cohorts aged 16–19. The main independent variables were type and frequency of electronic devices at bedtime and hours of screen-time during leisure time. Outcomes Sleep variables calculated based on self-report including bedtime, rise time, time in bed, sleep duration, sleep onset latency and wake after sleep onset. Results Adolescents spent a large amount of time during the day and at bedtime using electronic devices. Daytime and bedtime use of electronic devices were both related to sleep measures, with an increased risk of short sleep duration, long sleep onset latency and increased sleep deficiency. A dose–response relationship emerged between sleep duration and use of electronic devices, exemplified by the association between PC use and risk of less than 5?h of sleep (OR=2.70, 95% CI 2.14 to 3.39), and comparable lower odds for 7–8?h of sleep (OR=1.64, 95% CI 1.38 to 1.96). Conclusions Use of electronic devices is frequent in adolescence, during the day as well as at bedtime. The results demonstrate a negative relation between use of technology and sleep, suggesting that recommendations on healthy media use could include restrictions on electronic devices. PMID:25643702

Hysing, Mari; Pallesen, Ståle; Stormark, Kjell Morten; Jakobsen, Reidar; Lundervold, Astri J; Sivertsen, Børge

2015-01-01

280

ORIGIN OF THE UNUSUALLY LOW NITROGEN ABUNDANCES IN YOUNG POPULATIONS OF THE LARGE MAGELLANIC CLOUD  

SciTech Connect

It is a longstanding problem that H II regions and very young stellar populations in the Large Magellanic Cloud (LMC) have nitrogen abundances ([N/H]) that are a factor of {approx}7 lower than the solar value. We here discuss a new scenario in which the observed unusually low nitrogen abundances can be closely associated with recent collisions and subsequent accretion of H I high velocity clouds (HVCs) that surround the Galaxy and have low nitrogen abundances. We show that if the observed low [N/H] is limited to very young stars with ages less than {approx}10{sup 7} yr, then the collision/accretion rate of the HVCs onto the LMC needs to be {approx}0.2 M{sub sun} yr{sup -1} (corresponding to the total HVC mass of 10{sup 6}-10{sup 7} M{sub sun}) to dilute the original interstellar medium (ISM) before star formation. The required accretion rate means that even if the typical mass of HVCs accreted onto the LMC is {approx}10{sup 7} M{sub sun}, the Galaxy needs to have {approx}2500 massive HVCs within the LMC's orbital radius with respect to the Galactic center. The rather large number of required massive HVCs drives us to suggest that the HVCs are not likely to efficiently dilute the ISM of the LMC and consequently lower the [N/H]. We thus suggest the transfer of gas with low [N/H] from the Small Magellanic Cloud to the LMC as a promising scenario that can explain the observed low [N/H].

Bekki, Kenji [ICRAR, M468, University of Western Australia, 35 Stirling Highway, Crawley Western Australia 6009 (Australia); Tsujimoto, Takuji [National Astronomical Observatory, Mitaka-shi, Tokyo 181-8588 (Japan)

2010-10-01

281

Genetics of single-cell protein abundance variation in large yeast populations  

NASA Astrophysics Data System (ADS)

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 physiology between yeast strains.

Albert, Frank W.; Treusch, Sebastian; Shockley, Arthur H.; Bloom, Joshua S.; Kruglyak, Leonid

2014-02-01

282

Genetics of single-cell protein abundance variation in large yeast populations  

PubMed Central

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 multiple genes. The effects of such variants can be detected as expression quantitative trait loci (eQTL) 1. 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 2–6. Consequently, many eQTL are likely missed, especially those with smaller effects 7. Further, most studies use mRNA rather than protein abundance as the measure of gene expression. Studies that have used mass-spectrometry proteomics 8–13 reported surprising differences between eQTL and protein QTL (pQTL) for the same genes 9,10, 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 Saccharomyes 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 vs. 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 cluster at hotspot locations that influence multiple proteins—in some cases, more than half of those examined. The variants that underlie these hotspots have profound effects on the gene regulatory network and provide insights into genetic variation in cell physiology between yeast strains. PMID:24402228

Albert, Frank W.; Treusch, Sebastian; Shockley, Arthur H.; Bloom, Joshua S.; Kruglyak, Leonid

2014-01-01

283

Intraocular surgery in a large diabetes patient population: risk factors and surgical results.  

PubMed

The prevalence of diabetes is on the increase in developed countries. Accordingly, the prevention and treatment of vision-threatening diabetic eye complications is assuming greater importance. The overall aim of this thesis is to analyse risk factors for intraocular surgery in a large diabetes population and to report surgical results. The specific objectives are to (1) estimate the incidence of diabetic vitrectomy and analyse risk factors (Study I), (2) report long-term results, prognostic factors and incidence of cataract surgery after diabetic vitrectomy (Study II), (3) report results and prognostic factors after cataract surgery in diabetes patients (Study III) and (4) analyse risk factors for diabetic papillopathy with emphasis on metabolic control variability (Study IV). All studies are based on a close-to-complete national surgery register and a large, closely followed diabetic retinopathy screening population. Study I (cohort study, 3980 type 1 diabetes patients) illustrates that diabetic vitrectomy is rarely required in a diabetes patient population with varying degrees of diabetic retinopathy. The risk of reaching diabetic vitrectomy increases fourfold with poor metabolic control, defined as glycosylated haemoglobin A1c > 75 mmol/mol (~9%), which points to good metabolic control as an important preventive measure. Study II (cohort study, 167 diabetes patients) shows that most diabetic vitrectomy patients stand to gain visual acuity ?0.3 after surgery. Visual acuity is stable after 1 year, and the stability is maintained through 10 years of follow-up. The use of silicone oil for endotamponade is a consistent long-term predictor of low vision after surgery. The risk of requiring cataract surgery after diabetic vitrectomy is substantial, and the risk increases if silicone oil is used. Study III (cohort study, 285 diabetes patients) shows, on the other hand, that diabetes patients can expect a significant improvement in visual acuity after cataract surgery, regardless of the degree of diabetic retinopathy. Poor preoperative visual acuity, a high degree of diabetic retinopathy and advanced age are predictors of a poor visual acuity after surgery. The risk of diabetic macular oedema after surgery is 4%. Finally, Study IV (case-control study, 2066 type 1 diabetes patients) demonstrates that diabetic papillopathy shares characteristics with diabetic retinopathy. The risk of experiencing diabetic papillopathy increases markedly with a drastic, recent reduction in glycosylated haemoglobin A1c and a small optic disc. This lends support to the theory that diabetic eye complications may occur in anatomically predisposed patients in response to metabolic control variability. Overall, results after intraocular surgery in diabetes patients are favourable. Surgery, however, is associated with costs to society, patient discomfort and risk of complications. This thesis provides an analysis of risk factors for intraocular surgery and identifies prognostic factors for visual acuity after surgery, which can be used for preventive purposes, surgical decision-making and patient counselling. PMID:24809766

Ostri, Christoffer

2014-05-01

284

A large outbreak of shigellosis commencing in an internally displaced population, Papua New Guinea, 2013  

PubMed Central

Objective The objective of this study was to investigate a large outbreak of shigellosis in Papua New Guinea that began in a camp for internally displaced persons before spreading throughout the general community. Methods Outbreak mitigation strategies were implemented in the affected area to curtail the spread of the disease. Data were collected from the surveillance system and analysed by time, place and person. Rectal swab samples were tested by standard culture methods and real-time polymerase chain reaction to determine the etiology of the outbreak. Results Laboratory analysis at two independent institutions established that the outbreak was caused by Shigella sp., with one strain further characterized as Shigella flexneri serotype 2. Approximately 1200 suspected cases of shigellosis were reported in a two-month period from two townships in Morobe Province, Papua New Guinea. The outbreak resulted in at least five deaths, all in young children. Discussion This outbreak of shigellosis highlights the threat of enteric diseases to vulnerable populations such as internally displaced persons in Papua New Guinea, as has been observed in other global settings.

Benny, Edwin; Mesere, Kelly; Pavlin, Boris I; Yakam, Logan; Ford, Rebecca; Yoannes, Mition; Kisa, Debbie; Abdad, Mohammad Y; Menda, Lincoln; Greenhill, Andrew R

2014-01-01

285

Marine population connectivity: reconciling large-scale dispersal and high self-retention.  

PubMed

Abstract Predicting connectivity patterns in systems with fluid transport requires descriptions of the spatial distribution of propagules. In contrast to research on terrestrial seed dispersal, where much attention has focused on localized physical factors affecting dispersal, studies of oceanic propagule dispersal have often emphasized the role of large-scale factors. We link these two perspectives by exploring how propagule dispersal in the ocean is influenced by the "coastal boundary layer" (CBL), a region of reduced velocities near the shoreline that might substantially modify local-scale dispersal. We used a simple simulation model to demonstrate that accounting for the CBL markedly alters transport distances, the widths of dispersal distributions, and the fraction of larvae retained near their sites of origin (self-retention). Median dispersal distances were up to 59% shorter in simulations with a CBL than in those without. Self-retention of larvae increased by up to 3 orders of magnitude in the presence of CBLs, but only minor changes arose in the long-distance tails of the distributions, resulting in asymmetric, non-Gaussian kernels analogous to those quantified for terrestrial seed dispersal. Because successfully settling larvae are commonly those that remain close to shore and interact with the CBL, ignoring this pervasive oceanographic feature will substantially alter predictions of population self-persistence, estimates of connectivity, and outcomes of metapopulation analyses. PMID:25616139

Nickols, Kerry J; White, J Wilson; Largier, John L; Gaylord, Brian

2015-02-01

286

Population Structure and Dispersal Patterns within and between Atlantic and Mediterranean Populations of a Large-Range Pelagic Seabird  

PubMed Central

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

Genovart, Meritxell; Thibault, Jean-Claude; Igual, José Manuel; Bauzà-Ribot, Maria del Mar; Rabouam, Corinne; Bretagnolle, Vincent

2013-01-01

287

The Effective Population Size of Malaria Mosquitoes: Large Impact of Vector Control  

PubMed Central

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. PMID:23271973

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

288

Operational sex ratio, sexual conflict and the intensity of sexual selection  

E-print Network

LETTER Operational sex ratio, sexual conflict and the intensity of sexual selection Patrick S.fitze@mncn.csic.es Abstract Modern sexual selection theory indicates that reproductive costs rather than the operational sex when adult sex ratios (ASR) are male- biased. We manipulated ASR in 12 experimental populations

Alvarez, Nadir

289

Bem Sex Role Inventory Undifferentiated Score: A Comparison of Sexual Dysfunction Patients with Sexual Offenders.  

ERIC Educational Resources Information Center

Examined Bem Sex Role undifferentiated scores on 93 male sex offenders as compared with 50 male sexually dysfunctional patients. Chi-square analyses revealed significant difference: offenders obtained undifferentiated scores more often than did sexual dysfunctional population. Concluded that Bem Sex Role Inventory is useful in identifying sexual

Dwyer, Margretta; And Others

1988-01-01

290

Arsenic Exposure and Impaired Lung Function. Findings from a Large Population-based Prospective Cohort Study  

PubMed Central

Rationale: Exposure to arsenic through drinking water has been linked to respiratory symptoms, obstructive lung diseases, and mortality from respiratory diseases. Limited evidence for the deleterious effects on lung function exists among individuals exposed to a high dose of arsenic. Objectives: To determine the deleterious effects on lung function that exist among individuals exposed to a high dose of arsenic. Methods: In 950 individuals who presented with any respiratory symptom among a population-based cohort of 20,033 adults, we evaluated the association between arsenic exposure, measured by well water and urinary arsenic concentrations measured at baseline, and post-bronchodilator–administered pulmonary function assessed during follow-up. Measurements and Main Results: For every one SD increase in baseline water arsenic exposure, we observed a lower level of FEV1 (?46.5 ml; P < 0.0005) and FVC (?53.1 ml; P < 0.01) in regression models adjusted for age, sex, body mass index, smoking, socioeconomic status, betel nut use, and arsenical skin lesions status. Similar inverse relationships were observed between baseline urinary arsenic and FEV1 (?48.3 ml; P < 0.005) and FVC (?55.2 ml; P < 0.01) in adjusted models. Our analyses also demonstrated a dose-related decrease in lung function with increasing levels of baseline water and urinary arsenic. This association remained significant in never-smokers and individuals without skin lesions, and was stronger in male smokers. Among male smokers and individuals with skin lesions, every one SD increase in water arsenic was related to a significant reduction of FEV1 (?74.4 ml, P < 0.01; and ?116.1 ml, P < 0.05) and FVC (?72.8 ml, P = 0.02; and ?146.9 ml, P = 0.004), respectively. Conclusions: This large population-based study confirms that arsenic exposure is associated with impaired lung function and the deleterious effect is evident at low- to moderate-dose range. PMID:23848239

Parvez, Faruque; Chen, Yu; Yunus, Mahbub; Olopade, Christopher; Segers, Stephanie; Slavkovich, Vesna; Argos, Maria; Hasan, Rabiul; Ahmed, Alauddin; Islam, Tariqul; Akter, Mahmud M.; Graziano, Joseph H.

2013-01-01

291

Waterscape genetics of the yellow perch (Perca flavescens): patterns across large connected ecosystems and isolated relict populations.  

PubMed

Comparisons of a species' genetic diversity and divergence patterns across large connected populations vs. isolated relict areas provide important data for understanding potential response to global warming, habitat alterations and other perturbations. Aquatic taxa offer ideal case studies for interpreting these patterns, because their dispersal and gene flow often are constrained through narrow connectivity channels that have changed over geological time and/or from contemporary anthropogenic perturbations. Our research objective is to better understand the interplay between historic influences and modern-day factors (fishery exploitation, stocking supplementation and habitat loss) in shaping population genetic patterns of the yellow perch Perca flavescens (Percidae: Teleostei) across its native North American range. We employ a modified landscape genetics approach, analysing sequences from the entire mitochondrial DNA control region and 15 nuclear DNA microsatellite loci of 664 spawning adults from 24 populations. Results support that perch from primary glacial refugium areas (Missourian, Mississippian and Atlantic) founded contemporary northern populations. Genetic diversity today is highest in southern (never glaciated) populations and also is appreciable in northern areas that were founded from multiple refugia. Divergence is greater among isolated populations, both north and south; the southern Gulf Coast relict populations are the most divergent, reflecting their long history of isolation. Understanding the influence of past and current waterway connections on the genetic structure of yellow perch populations may help us to assess the roles of ongoing climate change and habitat disruptions towards conserving aquatic biodiversity. PMID:23078285

Sepulveda-Villet, Osvaldo J; Stepien, Carol A

2012-12-01

292

Evidence of large-scale source-sink dynamics and long-distance dispersal among Wood Thrush populations.  

PubMed

Source-sink dynamics are commonly thought to occur among Wood Thrush (Hylocichla mustelina) and other songbird populations, allowing for the persistence of populations with negative growth rates ("sinks") through immigration from populations with positive growth rates ("sources"). Knowledge of source-sink dynamics is important for management and conservation because the removal of source habitat should result in the extinction of dependent sinks. However, since research has focused on identifying individual sources/sink populations, not source-sink pairs, we cannot predict these effects or the scale over which they occur. We posit that, when dispersal occurs from a source to a sink year after year, there will be a one-year time-lagged correlation in abundance between the two populations. This should occur for populations separated by distances over which juveniles disperse. Using the North American Breeding Bird Survey data, we tested for such time-lagged correlations between paired Wood Thrush populations from 10 to 200 km apart. Populations were linked with a one-year time lag over distances from 60 to 80 km, indicating that dispersal and source-sink dynamics may occur over these long distances. There was also a declining trend in forest cover from sources to sinks. Conservation and management strategies should therefore be designed at large scales, with consideration for source-sink dynamics and forest cover. PMID:17249228

Tittler, Rebecca; Fahrig, Lenore; Villard, Marc-André

2006-12-01

293

Inferring the contribution of sexual reproduction, migration and off-season survival to the temporal maintenance of microbial populations: a case study on the wheat fungal pathogen Puccinia striiformis f.sp. tritici.  

PubMed

Understanding the mode of temporal maintenance of plant pathogens is an important domain of microbial ecology research. Due to the inconspicuous nature of microbes, their temporal maintenance cannot be studied directly through tracking individuals and their progeny. Here, we suggest a series of population genetic analyses on molecular marker variation in temporally spaced samples to infer about the relative contribution of sexual reproduction, off-season survival and migration to the temporal maintenance of pathogen populations. We used the proposed approach to investigate the temporal maintenance of wheat yellow rust pathogen, Puccinia striiformis f.sp. tritici (PST), in the Himalayan region of Pakistan. Multilocus microsatellite genotyping of PST isolates revealed high genotypic diversity and recombinant population structure across all locations, confirming the existence of sexual reproduction in this region. The genotypes were assigned to four genetic groups, revealing a clear differentiation between zones with and without Berberis spp., the alternate host of PST, with an additional subdivision within the Berberis zone. The lack of any differentiation between samples across two sampling years, and the very infrequent resampling of multilocus genotypes over years at a given location was consistent with limited over-year clonal survival, and a limited genetic drift. The off-season oversummering population in the Berberis zone, likely to be maintained locally, served as a source of migrants contributing to the temporal maintenance in the non-Berberis zone. Our study hence demonstrated the contribution of both sexual recombination and off-season oversummering survival to the temporal maintenance of the pathogen. These new insights into the population biology of PST highlight the general usefulness of the analytical approach proposed. PMID:24354737

Ali, Sajid; Gladieux, Pierre; Rahman, Hidayatur; Saqib, Muhammad S; Fiaz, Muhammad; Ahmad, Habib; Leconte, Marc; Gautier, Angélique; Justesen, Annemarie F; Hovmøller, Mogens S; Enjalbert, Jérôme; de Vallavieille-Pope, Claude

2014-02-01

294

Large delay in flowering in continental versus coastal populations of a Mediterranean shrub, Globularia alypum  

Microsoft Academic Search

Globularia alypum is a perennial shrub typical of western Mediterranean thermophilous shrublands. Nine populations of G. alypum located in different localities of Catalonia (NE Spain) were surveyed for flowering phenology. Flower-head buds were present\\u000a in all the populations in July. Flowering time in the area spans from the late summer–early autumn to the next spring depending\\u000a on the populations; there

Marc Estiarte; Gloria Puig; Josep Peñuelas

295

Men's reproductive and sexual health.  

PubMed

A broad definition of men's reproductive and sexual health (MRSH) includes medical (pathophysiological) matters such as sexually transmitted infections (STIs), developmental anomalies, malignancy, trauma, and infertility. It also includes psychosocial concerns: sexuality, contraception, disease prophylaxis, developmental and lifecycle issues, tobacco and drug use, sexual identity and orientation, and partnership issues. College men, of whom a large majority are sexually active, have a range of MRSH needs, including some that are particular to their age and social environment. To reach men effectively requires approaches that are somewhat different from those used with women. Clinicians in college health services are in an excellent position to help young men recognize the importance of reproductive health and sexual responsibility. College health services therefore should offer men screening; clinical diagnosis and treatment for MRSH conditions; and information, education, and counseling services, in a manner designed to meet their unique needs. PMID:11413943

Forrest, K A

2001-05-01

296

Postcopulatory Sexual Selection Reduces Genetic Diversity in Experimental  

E-print Network

Postcopulatory Sexual Selection Reduces Genetic Diversity in Experimental PopulationsMunyon at the address above, or e-mail: cwlamunyon@csupomona.edu. Abstract Postcopulatory sexual selection affects populations. By inference, we conclude that genetic hitchhiking due to sexual selection in the experimental

Cutter, Asher D.

297

Macular Pigment Optical Density in the Elderly: Findings in a Large Biracial Midsouth Population Sample  

PubMed Central

Purpose To report the macular pigment optical density (MPOD) findings at 0.5° of eccentricity from the fovea in elderly subjects participating in ARMA, a study of aging and age-related maculopathy (ARM) ancillary to the Health, Aging, and Body Composition (Health ABC) Study. Methods MPOD was estimated with a heterochromatic flicker photometry (HFP) method in a large biracial population sample of normal 79.1 ± 3.2-year-old adults living in the Midsouth (n = 222; 52% female; 23% black, 34% users of lutein-containing supplements). Within a modified testing protocol, subjects identified the lowest and the highest target intensity at which the flicker sensation disappeared, and the exact middle of this “no-flicker zone” was interpolated by the examiner. Results An MPOD estimate was obtained successfully in 82% of the participants. The mean MPOD in our sample was 0.34 ± 0.21 (SD). The interocular correlation was high (Pearson’s r = 0.82). Compared with lutein supplement users, mean MPOD was 21% lower in nonusers (P = 0.013). MPOD was also 41% lower in blacks than in whites (P = 0.0002), even after adjustment for lutein supplement use. There were no differences in MPOD by gender, iris color, or history of smoking. Conclusions Older adults in the Midsouth appear to have average MPOD and interocular correlation comparable to those in previous studies. Lutein supplement use and white race correlated with higher MPOD. No evidence of an age-related decline in MPOD was seen in the sample. The HFP method for the measurement of MPOD is feasible in epidemiologic investigations of the elderly, the group at highest risk of ARM. PMID:17389471

Iannaccone, Alessandro; Mura, Marco; Gallaher, Kevin T.; Johnson, Elizabeth J.; Todd, William Andrew; Kenyon, Emily; Harris, Tarsha L.; Harris, Tamara; Satterfield, Suzanne; Johnson, Karen C.; Kritchevsky, Stephen B.

2008-01-01

298

The incidence of cancer deaths among hypertensive patients in a large Chinese population: A cohort study.  

PubMed

Current evidence is mixed regarding the association between antihypertensive prescriptions and cancer mortality. We evaluated this association in a large Chinese hypertensive population. We followed for five years all patients who were prescribed their first-ever antihypertensive agents between 2001 and 2005 in a public healthcare sector of Hong Kong. The association between antihypertensive drug class and cancer mortality was evaluated by Cox proportional hazard models with propensity score matching. Age, gender, socioeconomic status, service settings, district of residence, proportion of days covered reflecting medication adherence, and the number of comorbidities were adjusted. From 217,910 eligible patients, 9500 (4.4%) died from cancer within five years after their first-ever antihypertensive prescription. Most cancer deaths occurred in the digestive (38.9%) and respiratory system (30.4%); the breast (6.2%); and the lympho-hematopoietic tissues (5.3%). The proportion of patients who died from cancer was the highest in the calcium channel blocker (CCB) group (6.5%), followed by thiazide diuretics (4.4%), angiotensin converting enzyme inhibitors (4.2%) and ?-blockers (2.6%). When compared with ?-blockers, patients prescribed CCBs (Adjusted Hazard Ratio [AHR]=1.406, 95% C.I. 1.334-1.482, p<0.001) were more likely to die from cancer. Thiazide users were also more likely to suffer from cancer deaths (AHR=1.364, 95% C.I. 1.255-1.483, p<0.001), but became insignificant in stratified analysis. The association between cancer mortality and use of CCB, and perhaps thaizide, may alert physicians to the need for more meticulous and comprehensive care of these patients in clinical practice. We recommend prospective studies to evaluate cause-and-effect relationships of these associations. PMID:25464439

Wong, Martin C S; Tam, Wilson W S; Lao, X Q; Wang, Harry H X; Kwan, Mandy W M; Cheung, Clement S K; Tong, Ellen L H; Cheung, N T; Griffiths, Sian M; Coats, Andrew J S

2015-01-20

299

No Evidence for Pre-Copulatory Sexual Selection on Sperm Length in a Passerine Bird  

PubMed Central

There is growing evidence that post-copulatory sexual selection, mediated by sperm competition, influences the evolution of sperm phenotypes. Evidence for pre-copulatory sexual selection effects on sperm traits, on the other hand, is rather scarce. A recent paper on the pied flycatcher, Ficedula hypoleuca, reported phenotypic associations between sperm length and two sexually selected male traits, i.e. plumage colour and arrival date, thus invoking pre-copulatory sexual selection for longer sperm. We were unable to replicate these associations with a larger data set from the same and two additional study populations; sperm length was not significantly related to either male plumage colour or arrival date. Furthermore, there was no significant difference in sperm length between populations despite marked differences in male plumage colour. We also found some evidence against the previously held assumption of longer sperm being qualitatively superior; longer sperm swam at the same speed as shorter sperm, but were less able to maintain speed over time. We argue that both empirical evidence and theoretical considerations suggest that the evolution of sperm morphology is not primarily associated with pre-copulatory sexual selection on male secondary sexual traits in this or other passerine bird species. The relatively large between-male variation in sperm length in this species is probably due to relaxed post-copulatory sexual selection. PMID:22384277

Lifjeld, Jan T.; Laskemoen, Terje; Kleven, Oddmund; Pedersen, A. Tiril M.; Lampe, Helene M.; Rudolfsen, Geir; Schmoll, Tim; Slagsvold, Tore

2012-01-01

300

The Problem... ! Sexual Assault & Sexual Harassment are  

E-print Network

SPEAK UP SPEAK OUT #12;The Problem... ! Sexual Assault & Sexual Harassment are underreported and sexual harassment seriously. " We continue to meet WSU's obligations under Title IX and under WSU's own Sexual Harassment ! Unwelcome sexual advances or other behavior of a sexual nature, when submission

VandeVord, Pamela

301

POPULATION III STAR FORMATION IN LARGE COSMOLOGICAL VOLUMES. I. HALO TEMPORAL AND PHYSICAL ENVIRONMENT  

SciTech Connect

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.

Crosby, Brian D.; O'Shea, Brian W.; Smith, Britton D. [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Turk, Matthew J. [Department of Astronomy, Columbia University, New York, NY 10025 (United States); Hahn, Oliver, E-mail: crosbyb1@msu.edu [Institute for Astronomy, ETH Zurich, CH-8093 Zuerich (Switzerland)

2013-08-20

302

Attitudes Toward Sexuality Among Nursing Home Residents  

Microsoft Academic Search

There is a paucity of data regarding sexuality among nursing home residents. The aim of the present study was to evaluate sexual attitudes in a group of independent residents in a large urban nursing home. Ten items covering different aspects of sexual attitude were scored by two board certified psychiatrists following a semistructured interview. The study was undertaken at a

Dov Aizenberg; Abraham Weizman; Yoram Barak

2002-01-01

303

Healthy sex and sexual health: new directions for studying outcomes of sexual health.  

PubMed

Sexual behavior is an important aspect of adolescent development with implications for well-being. These chapters highlight important perspectives on studying sexual health from a normative, developmental perspective, such as viewing a range of sexual behaviors as life events; considering potentially positive physical health, mental health, social health, and identity outcomes; examining both intraindividual and interindividual differences in outcomes; recognizing the romantic relationship context of sexual behavior; and understanding how sexual media may impact sexual health outcomes. We suggest new directions for studying sexual health outcomes, such as studying behaviors beyond vaginal sex and condom use, new methodologies such as latent class analysis, sophisticated longitudinal designs, and collection and analysis of dyadic data. We recommend research on populations underrepresented in sexual health research such as late adolescents who do not attend traditional universities and adolescents from ethnic/racial minorities. Finally, we consider future directions for sexuality education and prevention efforts. PMID:24962364

Lefkowitz, Eva S; Vasilenko, Sara A

2014-01-01

304

Teenage Sexuality  

MedlinePLUS

... Register About Us Contact Us My Cart Healthy Children > Ages & Stages > Teen > Dating & Sex > Teenage Sexuality Ages & Stages Listen Teenage Sexuality Article ... to Know, 2nd Edition Sports Success Rx! Your Child’s Prescription for the Best Experience HealthyChildren.org Post-it Notes Home Strength Training for Young Athletes ... Nutrition Driving Safety School Substance Abuse Young ...

305

Sexual selection  

Microsoft Academic Search

Competition over mates takes many forms and has far-reaching consequences for many organisms. Recent work suggests that relative reproductive rates of males and females, sperm competition and quality variation among mates affect the strength of sexual selection. Song, other display, body size, visual ornaments and material resource offerings are often sexually selected. There is much empirical evidence of mate choice,

Malte Andersson; Yoh Iwasa

1996-01-01

306

Population biology of eyeflukes in fish from a large fluvial ecosystem: the importance of gulls and habitat characteristics  

Microsoft Academic Search

Spottail shiners (Notropis hudsonius) were monitored for eyeflukes monthly at four sites in the St. Lawrence River, Quebec, from spring through autumn in 1997 and 1998. In general, mean abundance of Diplostomum spp. in the lens of spottail shiners was highest at sites near large ring-billed gull ( Larus delawarensis) colonies and was higher in 1998 than in 1997. Population

D. J. Marcogliese; S. Compagna; E. Bergeron; J. D. McLaughlin

2001-01-01

307

Sexual Dysfunction in Male Iraq and Afghanistan War Veterans: Association with Posttraumatic Stress Disorder and Other Combat-Related Mental Health Disorders: A Population-Based Cohort Study  

PubMed Central

Introduction Mental health disorders are prevalent in the United States, Iraq, and Afghanistan war veterans. Mental illness, including posttraumatic stress disorder (PTSD) with or without psychiatric medications, can increase the risk for male sexual dysfunction, threatening quality of life. Aims We sought to determine the prevalence and correlates of sexual dysfunction among male Iraq and Afghanistan veterans. Methods We performed a retrospective cohort study of 405,275 male Iraq and Afghanistan veterans who were new users of U.S. Department of Veterans Affairs healthcare from October 7, 2001 to September 30, 2009 and had 2-year follow-up. Main Outcome Measures We determined the independent association of mental health diagnoses and sexual dysfunction after adjusting for sociodemographic and military service characteristics, comorbidities, and medications. Results Veterans with PTSD were more likely to have a sexual dysfunction diagnosis, be prescribed medications for sexual dysfunction, or both (10.6%), compared with veterans having a mental diagnosis other than PTSD (7.2%), or no mental health diagnosis (2.3%). In a fully adjusted model, PTSD increased the risk of sexual dysfunction by more than threefold (adjusted risk ratio = 3.61, 95% CI = 3.48–3.75). Veterans with mental health disorders, particularly PTSD, were at the highest risk of sexual dysfunction when prescribed psychiatric medications (adjusted risk ratio = 4.59, 95% CI = 4.41–4.77). Conclusions Among U.S. combat veterans, mental health disorders, particularly PTSD, increased the risk of sexual dysfunction independent of the use of psychiatric medications. PMID:23679562

Breyer, Benjamin N.; Cohen, Beth E.; Bertenthal, Daniel; Rosen, Raymond C.; Neylan, Thomas C.; Seal, Karen H.

2014-01-01

308

Genetic variation in Fc? receptor IIa and risk of coronary heart disease: negative results from two large independent populations  

PubMed Central

Background The role of the Fc? receptor IIa (Fc?RIIa), a receptor for C-reactive protein (CRP), the classical acute phase protein, in atherosclerosis is not yet clear. We sought to investigate the association of Fc?RIIa genotype with risk of coronary heart disease (CHD) in two large population-based samples. Methods Fc?RIIa-R/H131 polymorphisms were determined in a population of 527 patients with a history of myocardial infarction and 527 age and gender matched controls drawn from a population-based MONICA- Augsburg survey. In the LURIC population, 2227 patients with angiographically proven CHD, defined as having at least one stenosis ? 50%, were compared with 1032 individuals with stenosis <50%. Results In both populations genotype frequencies of the Fc?RIIa gene did not show a significant departure from the Hardy-Weinberg equilibrium. Fc?RIIa R(-131) ? H genotype was not independently associated with lower risk of CHD after multivariable adjustments, neither in the MONICA population (odds ratio (OR) 1.08; 95% confidence interval (CI) 0.81 to 1.44), nor in LURIC (OR 0.96; 95% CI 0.81 to 1.14). Conclusion Our results do not confirm an independent relationship between Fc?RIIa genotypes and risk of CHD in these populations. PMID:19480687

Karakas, Mahir; Hoffmann, Michael M; Vollmert, Caren; Rothenbacher, Dietrich; Meisinger, Christa; Winkelmann, Bernhard; Khuseyinova, Natalie; Böhm, Bernhard O; Illig, Thomas; März, Winfried; Koenig, Wolfgang

2009-01-01

309

The impact of climate change on the bottom up regulation of density dependence in large herbivore populations  

NASA Astrophysics Data System (ADS)

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).

Ahrestani, F.; Smith, W. A.; Hebblewhite, M.; Running, S. W.; Post, E.

2013-12-01

310

The role of tetraploids in the sexual–asexual cycle in dandelions (Taraxacum)  

Microsoft Academic Search

Apomictic plants often produce pollen that can function in crosses with related sexuals. Moreover, facultative apomicts can produce some sexual offspring. In dandelions, Taraxacum, a sexual–asexual cycle between diploid sexuals and triploid apomicts, has been described, based on experimental crosses and population genetic studies. Little is known about the actual hybridization processes in nature. We therefore studied the sexual–asexual cycle

M. H. Verduijn; P J Van Dijk; J. M. M. Van Damme

2004-01-01

311

The Multiple Linkages Between Childhood Sexual Abuse, Adult Alcoholism, and Traumatic Brain Injury in Women  

Microsoft Academic Search

This paper examines the relationships between women, traumatic brain injury (TBI), alcohol dependency, and childhood sexual abuse. Alcohol use has increasingly been implicated as a direct cause of TBI occurrence. Because most TBI rehabilitation programs have been developed tor a male population, however, the unique relationship between women with TBI and alcohol dependency has largely been unexamined. Women with alcohol-related

Sharon A. Gutman; Peggy Swarbrick

1999-01-01

312

A Large Plasmodium vivax Reservoir and Little Population Structure in the South Pacific  

PubMed Central

Introduction The importance of Plasmodium vivax in malaria elimination is increasingly being recognized, yet little is known about its population size and population genetic structure in the South Pacific, an area that is the focus of intensified malaria control. Methods We have genotyped 13 microsatellite markers in 295 P. vivax isolates from four geographically distinct sites in Papua New Guinea (PNG) and one site from Solomon Islands, representing different transmission intensities. Results Diversity was very high with expected heterozygosity values ranging from 0.62 to 0.98 for the different markers. Effective population size was high (12?872 to 19?533 per site). In PNG population structuring was limited with moderate levels of genetic differentiation. FST values (adjusted for high diversity of markers) were 0.14–0.15. Slightly higher levels were observed between PNG populations and Solomon Islands (FST?=?0.16). Conclusions Low levels of population structure despite geographical barriers to transmission are in sharp contrast to results from regions of low P. vivax endemicity. Prior to intensification of malaria control programs in the study area, parasite diversity and effective population size remained high. PMID:23823758

Koepfli, Cristian; Timinao, Lincoln; Antao, Tiago; Barry, Alyssa E.; Siba, Peter; Mueller, Ivo; Felger, Ingrid

2013-01-01

313

Clonal growth is enhanced in the absence of a mating morph: a comparative study of fertile stylar polymorphic and sterile monomorphic populations of Nymphoides montana (Menyanthaceae)  

PubMed Central

Background and Aims Many aquatic species with stylar polymorphisms have the capacity for clonal and sexual reproduction and are sensitive to the balance of the two reproductive modes when there are a limited number of mating morphs within a population. This study asked how the clonal and sexual reproductive modes perform in populations that contain only a single morph and where fitness gain through sexual reproduction is rare. In clonal aquatic Nymphoides montana, polymorphic populations normally contain two mating morphs in equal frequencies. Populations are sexually fertile and appear to be maintained by pollen transfer between the two partners. However, in a monomorphic population of N. montana where mating opportunities are unavailable, female and male function is impaired and clonality maintains the population. Here, the consequences of intraspecific variation in sexuality were explored between monomorphic and polymorphic N. montana populations in eastern Australia. Methods Comparative measurements of male and female fertility, total dry mass and genotypic diversity using ISSR markers were made between populations with variable sexuality. Key Results and Conclusions Very few seeds were produced in the monomorphic population under natural and glasshouse conditions due to dysfunctional pollen and ovules. Stigma–anther separation was minimal in the monomorphic population, which may be a consequence of the relaxed selective pressures that regulate the maintenance of sexual function. However, clonal reproduction was favoured at the expense of sexual reproduction in the monomorphic population; this may facilitate the establishment of sterility throughout the population via resource reallocation or pleiotropic effects. The ISSR results showed that the monomorphic population was one large, single genotype, unlike the multi-genotypic fertile polymorphic populations. Evolutionary loss of sex in a clonal population in which a mating morph is absent was evident; under these conditions clonal growth may assure reproduction and expand the population via spreading stolons. PMID:24287813

Haddadchi, Azadeh; Fatemi, Mohammad; Gross, C. L.

2014-01-01

314

Nutritional correlates and mate acquisition role of multiple sexual traits in male collared flycatchers  

NASA Astrophysics Data System (ADS)

The information content of a sexual signal may predict its importance in a multiple signal system. Many studies have correlated sexual signal expression with the absolute levels of nutrient reserves. In contrast, the changes of nutrient reserves associated with signal expression are largely unknown in the wild due to technical limitations although they are important determinants of signal information content. We compared two visual and eight acoustic sexual traits in male collared flycatchers to see whether the nutritional correlates of expression predict the role of the signal in sexual selection. We used single point assays of plasma lipid metabolites to estimate short-term changes in nutritional state in relation to sexual trait expression during courtship. As a measure of sexual selection, we estimated the relationship with pairing latency after arrival in a 4-year dataset. Males which found a mate rapidly were characterized by large wing and forehead patches, but small song strophe complexity and small figure repertoire size. Traits more strongly related to pairing latency were also more closely related to changes in nutrient reserves. This indicates a link between signal role and information content. Small wing patches and, surprisingly, complex songs seemed to indicate poor phenotypic quality and were apparently disfavoured at mate acquisition in our population. Future studies of the information content of sexual traits, especially dynamic traits such as song, may benefit from the use of plasma metabolite profiles as non-invasive indicators of short-term changes in body condition.

Hegyi, Gergely; Szöll?si, Eszter; Jenni-Eiermann, Susanne; Török, János; Eens, Marcel; Garamszegi, László Zsolt

2010-06-01

315

Large fluctuations in the effective population size of the malaria mosquito Anopheles gambiae s.s. during vector control cycle  

PubMed Central

On Bioko Island, Equatorial Guinea, indoor residual spraying (IRS) has been part of the Bioko Island Malaria Control Project since early 2004. Despite success in reducing childhood infections, areas of high transmission remain on the island. We therefore examined fluctuations in the effective population size (Ne) of the malaria vector Anopheles gambiae in an area of persistent high transmission over two spray rounds. We analyzed data for 13 microsatellite loci from 791 An. gambiae specimens collected at six time points in 2009 and 2010 and reconstructed the demographic history of the population during this period using approximate Bayesian computation (ABC). Our analysis shows that IRS rounds have a large impact on Ne, reducing it by 65%–92% from prespray round Ne. More importantly, our analysis shows that after 3–5 months, the An. gambiae population rebounded by 2818% compared shortly following the spray round. Our study underscores the importance of adequate spray round frequency to provide continuous suppression of mosquito populations and that increased spray round frequency should substantially improve the efficacy of IRS campaigns. It also demonstrates the ability of ABC to reconstruct a detailed demographic history across only a few tens of generations in a large population. PMID:24478799

Hodges, Theresa K; Athrey, Giridhar; Deitz, Kevin C; Overgaard, Hans J; Matias, Abrahan; Caccone, Adalgisa; Slotman, Michel A

2013-01-01

316

Efficacy of methods for manipulating earthworm populations in large-scale field experiments in agroecosystems  

Microsoft Academic Search

We established a long-term field experiment in 1991 to investigate the influence of earthworms on C and N cycling processes in agroecosystems. In a replicated field experiment we decreased earthworm populations using electroshocking, increased them by adding field-collected worms or left them unmanipulated. Population manipulations and sampling were done twice per year in 20 m2 field enclosures that were made

P. J. Bohlen; R. W. Parmelee; J. M. Blair; C. A. Edwards; B. R. Stinner

1995-01-01

317

Dynamics of an emerging disease drive large-scale amphibian population extinctions  

PubMed Central

Epidemiological theory generally suggests that pathogens will not cause host extinctions because the pathogen should fade out when the host population is driven below some threshold density. An emerging infectious disease, chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd) is directly linked to the recent extinction or serious decline of hundreds of amphibian species. Despite continued spread of this pathogen into uninfected areas, the dynamics of the host–pathogen interaction remain unknown. We use fine-scale spatiotemporal data to describe (i) the invasion and spread of Bd through three lake basins, each containing multiple populations of the mountain yellow-legged frog, and (ii) the accompanying host–pathogen dynamics. Despite intensive sampling, Bd was not detected on frogs in study basins until just before epidemics began. Following Bd arrival in a basin, the disease spread to neighboring populations at ?700 m/yr in a wave-like pattern until all populations were infected. Within a population, infection prevalence rapidly reached 100% and infection intensity on individual frogs increased in parallel. Frog mass mortality began only when infection intensity reached a critical threshold and repeatedly led to extinction of populations. Our results indicate that the high growth rate and virulence of Bd allow the near-simultaneous infection and buildup of high infection intensities in all host individuals; subsequent host population crashes therefore occur before Bd is limited by density-dependent factors. Preventing infection intensities in host populations from reaching this threshold could provide an effective strategy to avoid the extinction of susceptible amphibian species in the wild. PMID:20457913

Vredenburg, Vance T.; Knapp, Roland A.; Tunstall, Tate S.; Briggs, Cheryl J.

2010-01-01

318

Dynamics of an emerging disease drive large-scale amphibian population extinctions.  

PubMed

Epidemiological theory generally suggests that pathogens will not cause host extinctions because the pathogen should fade out when the host population is driven below some threshold density. An emerging infectious disease, chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd) is directly linked to the recent extinction or serious decline of hundreds of amphibian species. Despite continued spread of this pathogen into uninfected areas, the dynamics of the host-pathogen interaction remain unknown. We use fine-scale spatiotemporal data to describe (i) the invasion and spread of Bd through three lake basins, each containing multiple populations of the mountain yellow-legged frog, and (ii) the accompanying host-pathogen dynamics. Despite intensive sampling, Bd was not detected on frogs in study basins until just before epidemics began. Following Bd arrival in a basin, the disease spread to neighboring populations at approximately 700 m/yr in a wave-like pattern until all populations were infected. Within a population, infection prevalence rapidly reached 100% and infection intensity on individual frogs increased in parallel. Frog mass mortality began only when infection intensity reached a critical threshold and repeatedly led to extinction of populations. Our results indicate that the high growth rate and virulence of Bd allow the near-simultaneous infection and buildup of high infection intensities in all host individuals; subsequent host population crashes therefore occur before Bd is limited by density-dependent factors. Preventing infection intensities in host populations from reaching this threshold could provide an effective strategy to avoid the extinction of susceptible amphibian species in the wild. PMID:20457913

Vredenburg, Vance T; Knapp, Roland A; Tunstall, Tate S; Briggs, Cheryl J

2010-05-25

319

[Sexually transmitted coinfections. HIV coinfections].  

PubMed

Coinfections of sexually transmitted infections are frequent due to the same transmission routes which may facilitate the transmission of other sexually transmitted infections. Sexually transmitted coinfections are associated with atypical and generally more severe clinical features, more complications, resistency to treatment, unfavourable outcome, and worse prognosis. Sexually transmitted infections may increase the likelihood of acquiring and transmission of HIV infection. The authors summarize the most important characteristics of sexually transmitted infections (such as HIV and hepatitis B virus, HIV and hepatitis C virus, HIV and syphilis, HIV and gonorrhoeae, HIV and chlamydia coinfections). These infections are more frequent in HIV infected patients than in the normal population. The shared transmission routes, impairment of the immune response, elevated cytokine levels and the associated inflammatory milieu produce local tissue damage, breaches in mucosal epithelium, which increases the risk of human immunodeficiency virus infection. Regular screening for sexually transmitted infections, use of more sensitive diagnostic methods, improved reporting and avoidance of unsafe sexual behaviour among certain subpopulations as well as education are essential in the prevention of sexually transmitted coinfections. Orv. Hetil., 2015, 156(1), 4-9. PMID:25544048

Marschalkó, Márta; Pónyai, Katinka; Kárpáti, Sarolta

2015-01-01

320

Variation in Craniomandibular Morphology and Sexual Dimorphism in Pantherines and the Sabercat Smilodon fatalis  

PubMed Central

Sexual dimorphism is widespread among carnivorans, and has been an important evolutionary factor in social ecology. However, its presence in sabertoothed felids remains contentious. Here we present a comprehensive analysis of extant Panthera and the sabertoothed felid Smilodon fatalis. S. fatalis has been reported to show little or no sexual dimorphism but to have been intraspecifically variable in skull morphology. We found that large and small specimens of S. fatalis could be assigned to male and female sexes with similar degrees of confidence as Panthera based on craniomandibular shape. P. uncia is much less craniomandibularly variable and has low levels of sexual size-dimorphism. Shape variation in S. fatalis probably reflects sexual differences. Craniomandibular size-dimorphism is lower in S. fatalis than in Panthera except P. uncia. Sexual dimorphism in felids is related to more than overall size, and S. fatalis and the four large Panthera species show marked and similar craniomandibular and dental morphometric sexual dimorphism, whereas morphometric dimorphism in P. uncia is less. Many morphometric-sexually dimorphic characters in Panthera and Smilodon are related to bite strength and presumably to killing ecology. This suggests that morphometric sexual dimorphism is an evolutionary adaptation to intraspecific resource partitioning, since large males with thicker upper canines and stronger bite forces would be able to hunt larger prey than females, which is corroborated by feeding ecology in P. leo. Sexual dimorphism indicates that S. fatalis could have been social, but it is unlikely that it lived in fusion-fission units dominated by one or a few males, as in sub-Saharan populations of P. leo. Instead, S. fatalis could have been solitary and polygynous, as most extant felids, or it may have lived in unisexual groups, as is common in P. leo persica. PMID:23110232

Christiansen, Per; Harris, John M.

2012-01-01

321

Sexual Problems  

MedlinePLUS

... that is, no pleasurable sexual sensations in her clitoris or vagina. Male erectile disorder, or ED, is ... fall under this category, including vibrators, dilators, and clitoral devices. Vibrators and dildos can be used by ...

322

Accuracy of genomic selection models in a large population of open-pollinated families in white spruce.  

PubMed

Genomic selection (GS) is of interest in breeding because of its potential for predicting the genetic value of individuals and increasing genetic gains per unit of time. To date, very few studies have reported empirical results of GS potential in the context of large population sizes and long breeding cycles such as for boreal trees. In this study, we assessed the effectiveness of marker-aided selection in an undomesticated white spruce (Picea glauca (Moench) Voss) population of large effective size using a GS approach. A discovery population of 1694 trees representative of 214 open-pollinated families from 43 natural populations was phenotyped for 12 wood and growth traits and genotyped for 6385 single-nucleotide polymorphisms (SNPs) mined in 2660 gene sequences. GS models were built to predict estimated breeding values using all the available SNPs or SNP subsets of the largest absolute effects, and they were validated using various cross-validation schemes. The accuracy of genomic estimated breeding values (GEBVs) varied from 0.327 to 0.435 when the training and the validation data sets shared half-sibs that were on average 90% of the accuracies achieved through traditionally estimated breeding values. The trend was also the same for validation across sites. As expected, the accuracy of GEBVs obtained after cross-validation with individuals of unknown relatedness was lower with about half of the accuracy achieved when half-sibs were present. We showed that with the marker densities used in the current study, predictions with low to moderate accuracy could be obtained within a large undomesticated population of related individuals, potentially resulting in larger gains per unit of time with GS than with the traditional approach. PMID:24781808

Beaulieu, J; Doerksen, T; Clément, S; MacKay, J; Bousquet, J

2014-10-01

323

Initial population of large-l Rydberg states for the radiative deexcitation in the beam-foil geometry  

NASA Astrophysics Data System (ADS)

In the recent beam-foil experiment, resonances have been observed in decay of the beam-foil excited 2p and 2s states of H-like Fe ions at very large times. Qualitatively, the resonances were explained as a consequence of cascading down from the Rydberg states (n?1,l=n-1) to 2p state. Full explanation requires the theoretical values of the population probabilities P of the large-l Rydberg states of multiply charged ions of core charges Z?1 a.u. escaping the solid surfaces at velocities v?1 a.u. The resonances observed in the time dependent photon intensity indicate the existence of resonances (pronounced maxima at several n=nres) in the P distributions. Considering the population process within the framework of the time-symmetrized two-state vector model, with dynamically generalized interaction Hamiltonian, we found that the nonresonant electron pick up from the foil conduction band into the field of ionic core when the ion leaves the surface represents an important population mechanism. The obtained population distributions have the resonance-like structure like the ones simulated from the experimental signal, and the overlap shape and magnitude in accordance with the wake field model estimations.

Nedeljkovi?, N. N.; Galijaš, S. M. D.; Mirkovi?, M. A.

2014-02-01

324

Exposure to Sexual Lyrics and Sexual Experience Among Urban Adolescents  

PubMed Central

Background Two thirds of all sexual references in music are degrading in nature, yet it remains uncertain whether these references promote earlier sexual activity. The purpose of this study was to determine if exposure to lyrics describing degrading sex in popular music is independently associated with sexual behavior in a cohort of urban adolescents. Methods All ninth-grade health students at three large urban high schools completed in-school surveys in 2006 and 2007. Participants’ exposure to lyrics describing degrading sex was computed with overall music exposure and content analyses of their favorite artists’ songs. Outcomes included sexual intercourse and progression along a noncoital sexual continuum. Multivariable regression was used to assess independent associations between exposure to lyrics describing degrading sex and outcomes. Results The 711 participants were exposed to 14.7 hours each week of songs with lyrics describing degrading sex (SD=17.0). Almost one third of participants (n=216) had previously been sexually active. Compared to those with the least exposure to lyrics describing degrading sex, those with the most exposure were more than twice as likely to have had sexual intercourse (OR=2.07; 95% CI=1.26, 3.41), even after adjusting for all covariates. Similarly, among those who had not had sexual intercourse, those in the highest tertile of exposure to lyrics describing degrading sex were nearly twice as likely to have progressed along a noncoital sexual continuum (OR=1.88; 95% CI=1.23, 2.88) compared to those in the lowest tertile. Finally, the relationships between exposure to lyrics describing nondegrading sex and sexual outcomes were not significant. Conclusions This study supports an association between exposure to lyrics describing degrading sex in popular music and early sexual experience among adolescents. PMID:19285196

Primack, Brian A.; Douglas, Erika L.; Fine, Michael J.; Dalton, Madeline A.

2010-01-01

325

TRANSGENIC PLANTS AND INSECTS A Multiyear, Large-Scale Comparison of Arthropod Populations on  

E-print Network

and plant bugs), and generalist natural enemies [Geocoris spp., Orius spp., Solenopsis invicta (Buren), their numbers were consistently signiÃ?cantly lower in the Bt cotton Ã?elds. Natural enemy populations generally, where signiÃ?cant differences were present, natural enemy abundance usuallywashigherinthe

Behmer, Spencer T.

326

A Metapopulation Model for Chikungunya Including Populations Mobility on a Large-Scale Network  

E-print Network

In this work we study the influence of populations mobility on the spread of a vector-borne disease. We focus on the chikungunya epidemic event that occurred in 2005-2006 on the R\\'eunion Island, Indian Ocean, France, and validate our models with real epidemic data from the event. We propose a metapopulation model to represent both a high-resolution patch model of the island with realistic population densities and also mobility models for humans (based on real-motion data) and mosquitoes. In this metapopulation network, two models are coupled: one for the dynamics of the mosquito population and one for the transmission of the disease. A high-resolution numerical model is created out from real geographical, demographical and mobility data. The Island is modeled with an 18 000-nodes metapopulation network. Numerical results show the impact of the geographical environment and populations' mobility on the spread of the disease. The model is finally validated against real epidemic data from the R\\'eunion event.

Moulay, Djamila

2012-01-01

327

Big Data: Large-Scale Historical Infrastructure from the Minnesota Population Center  

Microsoft Academic Search

The Minnesota Population Center (MPC) provides aggregate data and microdata that have been integrated and harmonized to maximize crosstemporal and cross-spatial comparability. All MPC data products are distributed free of charge through an interactive Web interface that enables users to limit the data and metadata being analyzed to samples and variables of interest to their research. In this article, the

Matthew Sobek; Lara Cleveland; Sarah Flood; Patricia Kelly Hall; Miriam L. King; Steven Ruggles; Matthew Schroeder

2011-01-01

328

Sexuality and intimacy in older adults.  

PubMed

In most long-term care settings, staff members tend to view a resident's attempts at sexual expression as "problem" behavior. However, we are increasingly recognizing that interest in, and the right to, sexual expression exists throughout the life span and should be supported. Assisted living nurses need information and tools to adequately address residents' sexual health and to overcome the many barriers to intimacy in this population. This article briefly reviews age and illness-related changes in sexual function; describes the research regarding older adults' and their family's and caregivers' attitudes regarding sexuality and intimacy; discusses sexuality and residents with dementia; and reviews nursing assessment and educational interventions that support healthy sexuality among older adults. PMID:18929184

Rheaume, Chris; Mitty, Ethel

2008-01-01

329

Household economy and population survey on a large agriculture-oriented county.  

PubMed

In this article household socioeconomic characteristics and standard of living are described for agricultural workers in Renshou County of Sichuan Province in western rural China. Data are obtained for the population in the county, and more detailed data are available among a sample of 215 households (743 persons) in 1993 in Anlin Village in Jinshun Township of Longzheng District. Anlin village is one of 1103 villages in the county. Family size declined during 1990-93 by 0.4 persons. 25.1% of households in Anlin Village had elderly members. 6.68% of elderly lived alone, and 8.22% lived in 2-person families. Over 60% lived in 3 or more generation households, and 27.4% lived in nuclear households. There were no homes for the aged in Anlin Village. All households were family, rather than collective, households. 8.04% of household heads were women. Total village population was 1110 persons. The sex ratio was normal. The village population aged under 15 years was lower, and the working age population was higher than the respective township populations. Marriages were stable and early marriage was not a problem. During 1990-93 the proportion with a junior high or more education increased as did the proportion illiterate or semi-literate. The working age population from rural statistics reports numbered 477 persons, of whom 92.9% were engaged in farming, animal farming, and fishing. 5.9% worked in non-agricultural jobs. 4.8% worked outside the area. The survey found a higher number of working age population than the 1993 annual report of rural statistics. Each person averaged 6.67 acres of arable land, and one in seven households owned cattle. Most households had electricity and bicycles. 56% had television sets. The average income was 1089.47 RMB yuan per person. In 1993, most women had one child and hoped to have a second one. Although regulations permitted only one child, most desired two and still relied on family support for the elderly. Renshou County is shifting from a subsistence economy to a diversified economy. It is expected that this shift eventually will create options for reducing family size. PMID:12291088

He, C; Chen, C

1995-01-01

330

Sustainably Harvesting a Large Carnivore? Development of Eurasian Lynx Populations in Norway During 160 Years of Shifting Policy  

NASA Astrophysics Data System (ADS)

The management of large carnivores in multiuse landscapes is always controversial, and managers need to balance a wide range of competing interests. Hunter harvest is often used to limit population size and distribution but is proving to be both controversialand technically challenging. Eurasian lynx ( Lynx lynx) are currently managed as a game species in Norway. We describe an adaptive management approach where quota setting is based on an annual census and chart the population development through the period 1996-2008, as management has become significantly more sophisticated and better informed by the increased availability of scientific data. During this period the population has been through a period of high quotas and population decline caused by fragmented management authority and overoptimistic estimates of lynx reproduction, followed by a period of recovery due to quota reductions. The modern management regime is placed in the context of shifting policy during the last 160 years, during which management goals have moved from extermination stimulated by bounties, through a short phase of protection, and now to quota-regulated harvest. Much management authority has also been delegated from central to local levels. We conclude that adaptive management has the potential to keep the population within some bounded limits, although there will inevitably be fluctuation.

Linnell, John D. C.; Broseth, Henrik; Odden, John; Nilsen, Erlend Birkeland

2010-05-01

331

Sexual Harassment and Sexual Bulllying  

MedlinePLUS

... sexual assault or rape, and it's a serious crime. Back Continue Flirting or Harassment? Sometimes people who ... worth it. It can help to keep a record of the events that have happened. Write down ...

332

Cryptic Sex within Male?Sterile Polyploid Populations of the Easter Daisy, Townsendia hookeri  

Microsoft Academic Search

After a transition from sexuality to asexuality, the evolutionary dynamics in apomictic lineages will largely depend on the frequency of recombination. We evaluated the presence and extent of asexuality and recom- bination within populations of the Easter daisy, Townsendia hookeri, from the Yukon Territory, Canada. Amplified fragment-length polymorphism (AFLP) fingerprints were used to genotype 78 individuals from four populations. Multilocus

Stacey Lee Thompson; Gina Choe; Kermit Ritland; Jeannette Whittony

2008-01-01

333

Mating patterns and contemporary gene flow by pollen in a large continuous and a small isolated population of the scattered forest tree Sorbus torminalis  

Microsoft Academic Search

The influence of population size and spatial isolation on contemporary gene flow by pollen and mating patterns in temperate forest trees are not well documented, although they are crucial factors in the life history of plant species. We analysed a small, isolated population and a large, continuous population of the insect-pollinated tree species Sorbus torminalis in two consecutive years. The

S E Hoebee; U Arnold; C Düggelin; F Gugerli; S Brodbeck; P Rotach; R Holderegger

2007-01-01

334

Changes in the Prevalence of Child Sexual Abuse, Its Risk Factors, and Their Associations as a Function of Age Cohort in a Finnish Population Sample  

ERIC Educational Resources Information Center

Objective: We examined (1) the prevalence of childhood sexual abuse (CSA) experiences as a function of cohort and gender, (2) the prevalence of factors associated with CSA as a function of cohort and whether the association of these factors with CSA remained the same irrespective of cohort, and (3) whether any cohort differences could be…

Laaksonen, Toni; Sariola, Heikki; Johansson, Ada; Jern, Patrick; Varjonen, Markus; von der Pahlen, Bettina; Sandnabba, N. Kenneth; Santtila, Pekka

2011-01-01

335

A trade-off between sexual signalling and immune function in a natural population of the drumming wolf spider Hygrolycosa rubrofasciata  

Microsoft Academic Search

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

J. J. AHTIAINEN; R. V. ALATALO; R. KORTET; M. J. RANTALA

2005-01-01

336

Sexual minority youth.  

PubMed

This article provides an overview of the medical and mental health needs of the lesbian, gay, bisexual, and transgender (LGBT) youth population. Information is reviewed regarding both primary medical care and the special health risks that these youth face. Providers are introduced to the concept that societal and internalized homophobia lead directly to certain health disparities, including substance use, school and family rejection, depression, and increased sexually transmitted infection acquisition. This article familiarizes the primary care practitioner with the health care needs of the LGBT population and the research behind the various recommendations for caring for these youth. PMID:25124211

Steever, John; Francis, Jenny; Gordon, Lonna P; Lee, Janet

2014-09-01

337

Birth seasonality and calf mortality in a large population of Asian elephants.  

PubMed

In seasonal environments, many species concentrate their reproduction in the time of year most likely to maximize offspring survival. Asian elephants (Elephas maximus) inhabit regions with seasonal climate, but females can still experience 16-week reproductive cycles throughout the year. Whether female elephants nevertheless concentrate births on periods with maximum offspring survival prospects remains unknown. We investigated the seasonal timing of births, and effects of birth month on short- and long-term mortality of Asian elephants, using a unique demographic data set of 2350 semicaptive, longitudinally monitored logging elephants from Myanmar experiencing seasonal variation in both workload and environmental conditions. Our results show variation in birth rate across the year, with 41% of births occurring between December and March. This corresponds to the cool, dry period and the beginning of the hot season, and to conceptions occurring during the resting, nonlogging period between February and June. Giving birth during the peak December to March period improves offspring survival, as the odds for survival between age 1 and 5 years are 44% higher for individuals born during the high birth rate period than those conceived during working months. Our results suggest that seasonal conditions, most likely maternal workload and/or climate, limit conception rate and calf survival in this population through effects on maternal stress, estrus cycles, or access to mates. This has implications for improving the birth rate and infant survival in captive populations by limiting workload of females of reproductive age. As working populations are currently unsustainable and supplemented through the capture of wild elephants, it is imperative to the conservation of Asian elephants to understand and alleviate the effects of seasonal conditions on vital rates in the working population in order to reduce the pressure for further capture from the wild. PMID:24198940

Mumby, Hannah S; Courtiol, Alexandre; Mar, Khyne U; Lummaa, Virpi

2013-10-01

338

DENSITY DEPENDENCE IN MARINE FISH POPULATIONS REVEALED AT SMALL AND LARGE SPATIAL SCALES  

Microsoft Academic Search

Experimental manipulation of population density has frequently been used to demonstrate demographic density dependence. However, such studies are usually small scale and typically provide evidence of spatial (within-generation) density dependence. It is often unclear whether small-scale, experimental tests of spatial density dependence will accurately describe temporal (between-generation) density dependence required for pop- ulation regulation. Understanding the mechanisms generating density dependence

DARREN W. J OHNSON

2006-01-01

339

Birth seasonality and calf mortality in a large population of Asian elephants  

PubMed Central

In seasonal environments, many species concentrate their reproduction in the time of year most likely to maximize offspring survival. Asian elephants (Elephas maximus) inhabit regions with seasonal climate, but females can still experience 16-week reproductive cycles throughout the year. Whether female elephants nevertheless concentrate births on periods with maximum offspring survival prospects remains unknown. We investigated the seasonal timing of births, and effects of birth month on short- and long-term mortality of Asian elephants, using a unique demographic data set of 2350 semicaptive, longitudinally monitored logging elephants from Myanmar experiencing seasonal variation in both workload and environmental conditions. Our results show variation in birth rate across the year, with 41% of births occurring between December and March. This corresponds to the cool, dry period and the beginning of the hot season, and to conceptions occurring during the resting, nonlogging period between February and June. Giving birth during the peak December to March period improves offspring survival, as the odds for survival between age 1 and 5 years are 44% higher for individuals born during the high birth rate period than those conceived during working months. Our results suggest that seasonal conditions, most likely maternal workload and/or climate, limit conception rate and calf survival in this population through effects on maternal stress, estrus cycles, or access to mates. This has implications for improving the birth rate and infant survival in captive populations by limiting workload of females of reproductive age. As working populations are currently unsustainable and supplemented through the capture of wild elephants, it is imperative to the conservation of Asian elephants to understand and alleviate the effects of seasonal conditions on vital rates in the working population in order to reduce the pressure for further capture from the wild. PMID:24198940

Mumby, Hannah S; Courtiol, Alexandre; Mar, Khyne U; Lummaa, Virpi

2013-01-01

340

Healthy Aging -- Sexual Health  

MedlinePLUS

... Healthy Aging This information in Spanish ( en español ) Sexual health More information on sexual health Many older women ... Protecting yourself Return to top More information on Sexual health Read more from womenshealth.gov Sexually Transmitted Infections ...

341

Geocoding large population-level administrative datasets at highly resolved spatial scales.  

PubMed

Using geographic information systems to link administrative databases with demographic, social, and environmental data allows researchers to use spatial approaches to explore relationships between exposures and health. Traditionally, spatial analysis in public health has focused on the county, zip code, or tract level because of limitations to geocoding at highly resolved scales. Using 2005 birth and death data from North Carolina, we examine our ability to geocode population-level datasets at three spatial resolutions - zip code, street, and parcel. We achieve high geocoding rates at all three resolutions, with statewide street geocoding rates of 88.0% for births and 93.2% for deaths. We observe differences in geocoding rates across demographics and health outcomes, with lower geocoding rates in disadvantaged populations and the most dramatic differences occurring across the urban-rural spectrum. Our results suggest highly resolved spatial data architectures for population-level datasets are viable through geocoding individual street addresses. We recommend routinely geocoding administrative datasets to the highest spatial resolution feasible, allowing public health researchers to choose the spatial resolution used in analysis based on an understanding of the spatial dimensions of the health outcomes and exposures being investigated. Such research, however, must acknowledge how disparate geocoding success across subpopulations may affect findings. PMID:25383017

Edwards, Sharon E; Strauss, Benjamin; Miranda, Marie Lynn

2014-08-01

342

Bladder cancer in cancer patients: population-based estimates from a large Swedish study  

PubMed Central

Background: This study quantified the risk of urinary bladder neoplasms in cancer patients taking into account the age at first diagnosis, the gender of the patients and the lead time between diagnoses. Methods: We used standardised incidence ratios (SIRs) to compare the incidence of bladder tumours in 967?767 cancer patients with the incidence rate in the general Swedish population. A total of 3324 male and 1560 female patients developed bladder tumours at least 1 year after first cancer diagnosis. Results: After bladder and renal pelvis cancers, the SIRs of bladder neoplasms were higher in female than in male patients. Men affected by lung, stomach and larynx tumours belonged to the population at high risk for bladder cancer. Treatment of breast, ovarian and cervical cancers seems to contribute to the subsequent development of bladder neoplasms. Long latencies (16–25 years) were observed after testicular, cervical and endometrial cancers. Detection bias had an important role after prostate cancer. Chemotherapy with cyclophosphamide and cisplatin, and also radiotherapy, seem to increase the risk of subsequent neoplasms in the bladder. Conclusions: These population-based results may help urologists to assess the risk of bladder neoplasms in cancer survivors. Our data should guide ongoing studies that investigate the effectiveness of bladder cancer screening in cancer patients. PMID:19755987

Bermejo, J Lorenzo; Sundquist, J; Hemminki, K

2009-01-01

343

Genetic variation reveals large-scale population expansion and migration during the expansion of Bantu-speaking peoples  

PubMed Central

The majority of sub-Saharan Africans today speak a number of closely related languages collectively referred to as ‘Bantu’ languages. The current distribution of Bantu-speaking populations has been found to largely be a consequence of the movement of people rather than a diffusion of language alone. Linguistic and single marker genetic studies have generated various hypotheses regarding the timing and the routes of the Bantu expansion, but these hypotheses have not been thoroughly investigated. In this study, we re-analysed microsatellite markers typed for large number of African populations that—owing to their fast mutation rates—capture signatures of recent population history. We confirm the spread of west African people across most of sub-Saharan Africa and estimated the expansion of Bantu-speaking groups, using a Bayesian approach, to around 5600 years ago. We tested four different divergence models for Bantu-speaking populations with a distribution comprising three geographical regions in Africa. We found that the most likely model for the movement of the eastern branch of Bantu-speakers involves migration of Bantu-speaking groups to the east followed by migration to the south. This model, however, is only marginally more likely than other models, which might indicate direct movement from the west and/or significant gene flow with the western Branch of Bantu-speakers. Our study use multi-loci genetic data to explicitly investigate the timing and mode of the Bantu expansion and it demonstrates that west African groups rapidly expanded both in numbers and over a large geographical area, affirming the fact that the Bantu expansion was one of the most dramatic demographic events in human history. PMID:25209939

Li, Sen; Schlebusch, Carina; Jakobsson, Mattias

2014-01-01

344

Hormone Replacement Therapy, Oral Contraceptive Use and Distal Large Bowel Cancer: A Population-Based Case-Control Study  

PubMed Central

Objective Lower incidence rates of distal large bowel cancer in women compared to men support the protective role of female hormones. We aimed to determine the associations between hormone replacement therapy, oral contraceptive use and distal large bowel cancer. Methods We conducted a population-based case-control study of incident distal large bowel cancer in North Carolina between 2001–2006. Data on hormone replacement therapy, oral contraceptive use, demographics and risk factors were obtained via in-person interviews. Odds ratios and 95% confidence intervals for the associations between oral contraceptive use, hormone replacement therapy and distal large bowel cancer were estimated via unconditional logistic regression models overall, by duration of use, and within strata of race. Results There were a total of 443 women with distal large bowel cancer and 405 controls. Ever use of hormone replacement therapy was strongly associated with a reduced risk of distal large bowel cancer (OR 0.52, 95% CI 0.38–0.72). Further reduction of distal large bowel cancer risk occurred with increased duration of use [<4 years (OR 0.77, 95% CI 0.44–1.35), 4–8 years (OR 0.64, 95% CI 0.37–1.10), 9–14 years (OR 0.47, 95% CI 0.27–0.81), ?15 years (OR 0.34, 95% CI 0.20–0.58)]. Ever use of oral contraceptives was not associated with reduced incidence of distal large bowel cancer (OR 0.95, 95% CI 0.67–1.34), nor was duration of use. There were no differences by race. Conclusions Hormone replacement therapy is associated with a lower risk of distal large bowel cancer. This risk is further reduced with increased duration of use. Hormone replacement therapy may be partially responsible for the reduced incidence of distal large bowel cancer in women compared to men. PMID:20354510

Long, Millie D.; Martin, Christopher F.; Galanko, Joseph A.; Sandler, Robert S.

2010-01-01

345

[Adolescent sexuality].  

PubMed

Between 1975-79, adolescents between ages 14-18 in Austrian schools were questioned about their sexual behavior. In contrast to earlier reports, an increased incidence and earlier onset of premarital sexual activity was seen. Of the 2809 individuals questioned, 41% of the females and 36% of the males had already had intercourse. There was a strong age dependence. At age 16, 30% had already engaged in sex; 49% at age 17; 65% at age 18; and 75% at age 19. Prior to age 16, 23% had already had intercourse. Early physical maturation (acceleration) freedom both sexually and morally, and a greater independence from the ethical and moral authority of the church seem to play a major part in this development. Love and fidelity play a major role among young people. The change of partners and promiscuity are not typical behavioral features among young people. The reproductive function of sexual activity is of no concern to young people; this aspect of sexuality must be eliminated through contraception. Contraception is a central topic for young people. 85% of this group do not feel that early onset of intercourse contradicts marriage. 95% of all young people want to marry and have a family at a later date. (author's modified) PMID:7112445

Husslein, A

1982-06-01

346

Mechanisms that control bacterial populations in continuous-flow culture models of mouse large intestinal flora.  

PubMed

A previous study had established that anaerobic continuous-flow (CF) cultures of conventional mouse cecal flora were able to maintain the in vivo ecological balance among the indigenous bacterial species tested. This paper describes experiments designed to determine the mechanisms which control the population sizes of these species in such CF cultures. One strain each of Escherichia coli, Fusobacterium sp., and Eubacterium sp. were studied. Growth of these strains in filtrates of CF cultures was considerably more rapid than in the CF cultures themselves, indicating that the inhibitory activity had been lost in the process of filtration. Growth rates to match those in CF cultures could be obtained, however, by restoring the original levels of H(2)S in the culture filtrates. The inhibitory effect of H(2)S in filtrates and in dialysates of CF cultures could be abolished by adding glucose or pyruvate, but not formate or lactate. The fatty acids present in CF cultures matched those in the cecum of conventional mice in both quality and concentration. These acids could not account for the slow rates of growth of the tested strains in CF cultures, but they did cause a marked increase in the initial lag phase of E. coli growth. The results obtained are compatible with the hypothesis that the populations of most indigenous intestinal bacteria are controlled by one or a few nutritional substrates which a given strain can utilize most efficiently in the presence of H(2)S and at the prevailing conditions of pH and anaerobiosis. This hypothesis consequently implies that the populations of enterobacteria, such as the E. coli strain tested, and those of the predominant anaerobes are controlled by analogous mechanisms. PMID:6339388

Freter, R; Brickner, H; Botney, M; Cleven, D; Aranki, A

1983-02-01

347

Browsing Large Pedigrees to Study of the Isolated Populations in the \\  

Microsoft Academic Search

\\u000a The paper reports a flow analysis framework for data exploration, knowledge discovery and visualization of large-scale Pedigrees\\u000a represented as directed graphs. Indeed, when large Pedigrees are involved in biological studies researchers need to interact\\u000a with multiple tools such as databases (storing genetic as well as phenotype information), graph browsers, graph visualization\\u000a tools, etc.\\u000a \\u000a \\u000a We have already collected the last three

Giuliano Antoniol; Michele Ceccarelli; Vincenzo Fabio Rollo; Wanda Longo; Teresa Nutile; Marina Ciullo; Enza Colonna; Antonietta Calabria; Maria Astore; Anna Lembo; Paola Toriello; M. Grazia Persico

2003-01-01

348

surprisingly large majority of the UK population are unaware of the  

E-print Network

bumblebees (genus Bombus) and honeybees (Apis mel- lifera). Bumblebees are the large, furry and often. Honeybees, widely kept in domestic hives for their honey, are smaller, slender, drab and rela- tively services to crops and wildflowers, what can be done to halt and reverse their decline? David Goulson

349

Child Sexual Abuse: Crimes, Victims, Offender Characteristics, and Recidivism.  

E-print Network

??Background: Epidemiological research on child sexual abuse relies on health care surveys, anonymized population surveys, and criminal statistics, each with its methodological limitations. This study… (more)

Carlstedt, Anita

2012-01-01

350

Statistics of Stellar Populations of Star Clusters and Surrounding Fields in the Outer Disk of the Large Magellanic Cloud  

E-print Network

A comparative analysis of Washington color-magnitude diagrams (CMDs) for 14 star clusters and respective surrounding fields in the Large Magellanic Cloud (LMC) outer disk is presented. Each CCD frame including field and respective cluster covers an area of 185 arcmin^2. The stellar population sampled is of intermediate age and metallicity. CMD radial analysis involving star count ratios, morphology and integrated light properties are carried out. Luminosity functions (LFs) are also presented. Two main results are: (i) Within the range 4populations, as inferred from red giant clump star counts.

Santos, J F C; Claria, J J; Bica, E; Geisler, D; Dottori, H

1999-01-01

351

Statistics of Stellar Populations of Star Clusters and Surrounding Fields in the Outer Disk of the Large Magellanic Cloud  

E-print Network

A comparative analysis of Washington color-magnitude diagrams (CMDs) for 14 star clusters and respective surrounding fields in the Large Magellanic Cloud (LMC) outer disk is presented. Each CCD frame including field and respective cluster covers an area of 185 arcmin^2. The stellar population sampled is of intermediate age and metallicity. CMD radial analysis involving star count ratios, morphology and integrated light properties are carried out. Luminosity functions (LFs) are also presented. Two main results are: (i) Within the range 4populations, as inferred from red giant clump star counts.

J. F. C. Santos Jr.; A. E. Piatti; J. J. Claria; E. Bica; D. Geisler; H. Dottori

1999-03-22

352

Population genetic structure of Arctic charr, Salvelinus alpinus from northwest Europe on large and small spatial scales.  

PubMed

To examine the population genetic structure of lake-resident Arctic charr, Salvelinus alpinus from northwest Europe on multiple spatial scales, 2367 individuals from 43 lakes located in three geographical regions (Iceland, the British Isles and Scandinavia) were genotyped at six microsatellite loci. On a large scale, data provided little evidence to support clustering of populations according to geographical region. Hierarchical analysis of molecular variance indicated that, although statistically significant, only 2.17% of the variance in allelic frequencies was partitioned at the among-region level. Within regions, high levels of genetic differentiation were typically found between lakes regardless of the geographical distance separating them. These results are consistent with the hypothesis of rapid postglacial recolonization of all of northwest Europe from a single charr lineage, with subsequent restriction of gene flow. On a smaller scale, there was evidence for close genetic relationships among lakes from within common drainage basins in Scotland. Thus, interlake genetic structure reflects localized patterns of recent (or contemporary) gene flow superimposed onto a larger scale structure that is largely a result of historical processes. There was also evidence for widespread genetic structuring at the within-lake level, with sympatric populations detected in 10 lakes, and multilocus heterozygote deficits found in 23 lakes. This evidence of the Wahlund effect was found in all lakes known to contain discrete phenotypic morphs, as well as many others, suggesting that morphs may often represent separate breeding populations, and also that the phenomenon of polymorphism in this species may be more widespread than is currently realized. PMID:15078451

Wilson, A J; Gíslason, D; Skúlason, S; Snorrason, S S; Adams, C E; Alexander, G; Danzmann, R G; Ferguson, M M

2004-05-01

353

A Genetic Analysis of Bald Eagles in the Pacific Northwest: Retained Genetic Diversity Following a Large-Scale Population Bottleneck.  

E-print Network

??Bald eagle (Haliaeetus leucocephalus) populations in the continental United States experienced a dramatic population decline during the twentieth century. Populations across the species’ range have… (more)

Nadeau, Andrew Joseph

2012-01-01

354

The Effectiveness of HIV/AIDS School-Based Sexual Health Education Programmes in Nigeria: A Systematic Review  

ERIC Educational Resources Information Center

HIV/AIDS is one of the most important public health challenges facing Nigeria today. Recent evidence has revealed that the adolescent population make up a large proportion of the 3.7% reported prevalence rate among Nigerians aged 15-49 years. School-based sexual health education has therefore become an important tool towards fighting this problem.…

Amaugo, Lucky Gospel; Papadopoulos, Chris; Ochieng, Bertha M. N.; Ali, Nasreen

2014-01-01

355

IL23R Haplotypes Provide A Large Population Attributable Risk for Crohn’s Disease  

PubMed Central

The IL-23 pathway plays a pivotal role in the development of chronic mucosal inflammation seen in the inflammatory bowel diseases. Multiple studies have now established the contribution of the interleukin 23 receptor gene (IL23R) to Crohn’s Disease (CD) risk in general and of the IL23R R381Q variant in particular. The aim of this work was to estimate the total contribution of this gene to CD risk test using a haplotype approach. Methods 763 CD subjects and 254 controls were genotyped for single nucleotide polymorphisms in the IL23R gene using Illumina and ABI methods. Haplotypes were assigned using PHASEv2 and tested for association with CD by chi-square and permutation. Results Haplotypes with both increased and decreased risk for CD were observed in 2 of the 4 observed blocks (Block 2 H1: 55.4% control, 64% CD, p=0.019; H2: 64.5% control, 54.4% CD, p=0.006; Block 3 H1: 55.8% control, 64.4% CD, p=0.013; H2: 47.0% control, 36.6% CD, p=0.001). The population attributable risk for these haplotypes was substantially larger than that estimated for the IL23R R381Q variant (Block 2 H1 and block 3 H1 ~20%, compared with ~4% for Block 3 H6, containing the variant). Discussion These observations suggest that IL23R makes a substantial contribution to Crohn’s disease susceptibility, larger than that estimated from the population frequency of the R381Q variant. These observations also support the expectation that finding “hits” from genome wide association studies will be but an important chapter in the story of unraveling the genetic contribution to Crohn’s disease, rather than the final chapter that brings clarity to all the plot twists of a complicated story. PMID:18470928

Taylor, Kent D.; Targan, Stephan R.; Mei, Ling; Ippoliti, Andrew F.; McGovern, Dermot; Mengesha, Emebet; King, Lily; Rotter, Jerome I.

2008-01-01

356

Evolution of male life histories and age-dependent sexual signals under female choice  

PubMed Central

Sexual selection theory models evolution of sexual signals and preferences using simple life histories. However, life-history models predict that males benefit from increasing sexual investment approaching old age, producing age-dependent sexual traits. Age-dependent traits require time and energy to grow, and will not fully mature before individuals enter mating competition. Early evolutionary stages pose several problems for these traits. Age-dependent traits suffer from strong viability selection and gain little benefit from mate choice when rare. Few males will grow large traits, and they will rarely encounter choosy females. The evolutionary origins of age-dependent traits therefore remain unclear. I used numerical simulations to analyze evolution of preferences, condition (viability) and traits in an age-structured population. Traits in the model depended on age and condition (“good genes”) in a population with no genetic drift. I asked (1) if age-dependent indicator traits and their preferences can originate depending on the strength of selection and the size of the trait; (2) which mode of development (age-dependent versus age-independent) eventually predominates when both modes occur in the population; and (3) if age-independent traits can invade a population with age-dependent traits. Age-dependent traits evolve under weaker selection and at smaller sizes than age-independent traits. This result held in isolation and when the types co-occur. Evolution of age-independent traits depends only on trait size, whereas evolution of age-dependent traits depends on both strength of selection and growth rate. Invasion of age-independence into populations with established traits followed a similar pattern with age-dependence predominating at small trait sizes. I suggest that reduced adult mortality facilitates sexual selection by favoring the evolution of age-dependent sexual signals under weak selection. PMID:24392289

2013-01-01

357

Thoreau's Sexuality  

Microsoft Academic Search

Although Henry David Thoreau (1817-1862) has often been described as lacking in sexual drive or at most a rather reluctant heterosexual, a close study of his life and writings indicates the presence of a pronounced vein of homoeroticism-although there seems to be no concrete evidence of any homosexual activity on his part. Cognizance of that homoeroticism helps one to understand

Walter Harding

1991-01-01

358

CLUSTERING OF LARGE CELL POPULATIONS: METHOD AND APPLICATION TO THE BASAL FOREBRAIN CHOLINERGIC SYSTEM  

PubMed Central

Functionally related groups of neurons spatially cluster together in the brain. To detect groups of functionally related neurons from 3D histological data, we developed an objective clustering method that provides a description of detected cell clusters that is quantitative and amenable to visual exploration. This method is based on bubble clustering (Gupta and Gosh, 2008). Our implementation consists of three steps: (i) an initial data exploration for scanning the clustering parameter space; (ii) determination of the optimal clustering parameters; (iii) final clustering. We designed this algorithm to flexibly detect clusters without assumptions about the underlying cell distribution within a cluster or the number and sizes of clusters. We implemented the clustering function as an integral part of the neuroanatomical data visualization software Virtual RatBrain (http://www.virtualratbrain.org). We applied this algorithm to the basal forebrain cholinergic system, which consists of a diffuse but inhomogeneous population of neurons (Zaborszky, 1992). With this clustering method, we confirmed the inhomogeneity in this system, defined cell clusters, quantified and localized them, and determined the cell density within clusters. Furthermore, by applying the clustering method to multiple specimens from both rat and monkey, we found that cholinergic clusters display remarkable cross-species preservation of cell density within clusters. This method is efficient not only for clustering cell body distributions but may also be used to study other distributed neuronal structural elements, including synapses, receptors, dendritic spines and molecular markers. PMID:20398701

Nadasdy, Zoltan; Varsanyi, Peter; Zaborszky, Laszlo

2010-01-01

359

Sexual Abstinence: the role of religion, peers and family  

E-print Network

in risky sexual practices. Research has explored the sex-related knowledge, attitudes and behaviors of the sexually active, often focusing on this population's risky behavior in relation to STD's, AIDS, and issues of contraception (Pollock and Brown 1981... abstinent, although they were participating in other sexual behaviors (oral or anal sex). In a pilot study for this research, it was found that approximately 10'to of the respondents who answered "no" to the question "have you had sexual intercourse...

Hunter-Holmes, Pamela

1997-01-01

360

Large indoor cage study of the suppression of stable Aedes aegypti populations by the release of thiotepa-sterilised males  

PubMed Central

The sterile insect technique (SIT) is a promising pest control method in terms of efficacy and environmental compatibility. In this study, we determined the efficacy of thiotepa-sterilised males in reducing the target Aedes aegypti populations. Treated male pupae were released weekly into large laboratory cages at a constant ratio of either 5:1 or 2:1 sterile-to-fertile males. A two-to-one release ratio reduced the hatch rate of eggs laid in the cage by approximately a third and reduced the adult catch rate by approximately a quarter, but a 5:1 release drove the population to elimination after 15 weeks of release. These results indicate that thiotepa exposure is an effective means of sterilising Ae. aegypti and males thus treated are able to reduce the reproductive capacity of a stable population under laboratory conditions. Further testing of the method in semi-field enclosures is required to evaluate the mating competitiveness of sterile males when exposed to natural environmental conditions. If proven effective, SIT using thiotepa-sterilised males may be incorporated into an integrated programme of vector control to combat dengue in Cuba. PMID:24863972

Gato, René; Lees, Rosemary Susan; Bruzon, Rosa Y; Companioni, Ariamys; Menendez, Zulema; González, Aileen; Rodríguez, Misladys

2014-01-01

361

Models for WR and O Star Populations in Starbursts: New Developments and Applications to Large Samples of WR Galaxies  

E-print Network

We summarise recent developments on synthesis models for massive star populations with a particular emphasis on Wolf-Rayet (WR) stars. Quantitative analysis of the stellar content of WR galaxies are reviewed. Comparing observations of WR galaxies from various samples with synthesis models we derive constraints on their burst properties. The observations indicate very short burst periods and are generally compatible with a Salpeter IMF and a large upper mass cut-off. The use of the Hbeta equivalent width as an age indicator works well for WR galaxies. We briefly summarise comparisons of stellar populations in super star clusters which also provide useful contraints on evolutionary models for massive stars e.g. at very low metallicities inaccessible in the Local Group. In particular the observed WN and WC populations favour the high mass loss models of Meynet et al. (1994). Finally we review recent work on the origin of nebular HeII emission. From the new catalogue of WR galaxies and high excitation HII regions of Schaerer et al. (1998) we find a close relation between the presence of nebular HeII and WR stars. The analysis of individual WR galaxies including I Zw 18 supports the suggestion of Schaerer (1996) that hot WR stars are responsible for the hard ionizing flux.

Daniel Schaerer

1998-12-21

362

Service utilization among older adults with HIV: the joint association of sexual identity and gender.  

PubMed

This study examines the association of sexual identity and gender among older clients with HIV at an AIDS service organization using the Andersen Model. Data confirm those aging with HIV exhibit high rates of age-associated illnesses 10 to 20 years before expected. They have fragile social networks that cannot supply the informal supports needed. This aging population will need to increasingly access community-based services. Sexual identity and gender were weak covariates of service utilization. Although heterosexual men used more services, utilization was largely predicted by service needs and the use of case management. Implications for service delivery and policy are discussed. PMID:24313258

Brennan-Ing, Mark; Seidel, Liz; London, Andrew S; Cahill, Sean; Karpiak, Stephen E

2014-01-01

363

Sexual segregation of pelagic sharks and the potential threat from fisheries  

PubMed Central

Large pelagic sharks are declining in abundance in many oceans owing to fisheries exploitation. What is not known however is whether within-species geographical segregation of the sexes exacerbates this as a consequence of differential exploitation by spatially focused fisheries. Here we show striking sexual segregation in the fastest swimming shark, the shortfin mako Isurus oxyrinchus, across the South Pacific Ocean. The novel finding of a sexual ‘line in the sea’ spans a historical longline-fishing intensity gradient, suggesting that differential exploitation of the sexes is possible, a phenomenon which may underlie changes in the shark populations observed elsewhere. PMID:19324655

Mucientes, Gonzalo R.; Queiroz, Nuno; Sousa, Lara L.; Tarroso, Pedro; Sims, David W.

2009-01-01

364

Agro-ecosystems impact malaria prevalence: large-scale irrigation drives vector population in western Ethiopia  

PubMed Central

Background Development strategies in Ethiopia have largely focused on the expansion of irrigated agriculture in the last decade to reduce poverty and promote economic growth. However, such irrigation schemes can worsen the socio-economic state by aggravating the problem of mosquito-borne diseases. In this study, the effect of agro-ecosystem practices on malaria prevalence and the risk of malaria transmission by the primary vector mosquito, Anopheles arabiensis, in Ethiopia were investigated. Methods In three villages in western Ethiopia practising large-scale sugarcane irrigation, traditional smallholder irrigation and non-irrigated farming, cross-sectional parasitological surveys were conducted during the short rains, after the long rains and during the dry season. Entomological surveys were undertaken monthly (February 2010-January 2011) in each village using light traps, pyrethrum spray collections and artificial pit shelters. Results Malaria prevalence and the risk of transmission by An. arabiensis assessed by the average human biting rate, mean sporozoite rate and estimated annual entomological inoculation rate were significantly higher in the irrigated sugarcane agro-ecosystem compared to the traditionally irrigated and non-irrigated agro-ecosystems. The average human biting rate was significantly elevated by two-fold, while the mean sporozoite rate was 2.5-fold higher, and the annual entomological inoculation rate was 4.6 to 5.7-fold higher in the irrigated sugarcane compared to the traditional and non-irrigated agro-ecosystems. Active irrigation clearly affected malaria prevalence by increasing the abundance of host seeking Anopheles mosquitoes year-round and thus increasing the risk of infective bites. The year-round presence of sporozoite-infected vectors due to irrigation practices was found to strengthen the coupling between rainfall and risk of malaria transmission, both on- and off-season. Conclusion This study demonstrates the negative impact of large-scale irrigation expansion on malaria transmission by increasing the abundance of mosquito vectors and indicates the need for effective vector monitoring and control strategies in the implementation of irrigation projects. PMID:24083353

2013-01-01

365

Variability in mutational fitness effects prevents full lethal transitions in large quasispecies populations.  

PubMed

The distribution of mutational fitness effects (DMFE) is crucial to the evolutionary fate of quasispecies. In this article we analyze the effect of the DMFE on the dynamics of a large quasispecies by means of a phenotypic version of the classic Eigen's model that incorporates beneficial, neutral, deleterious, and lethal mutations. By parameterizing the model with available experimental data on the DMFE of Vesicular stomatitis virus (VSV) and Tobacco etch virus (TEV), we found that increasing mutation does not totally push the entire viral quasispecies towards deleterious or lethal regions of the phenotypic sequence space. The probability of finding regions in the parameter space of the general model that results in a quasispecies only composed by lethal phenotypes is extremely small at equilibrium and in transient times. The implications of our findings can be extended to other scenarios, such as lethal mutagenesis or genomically unstable cancer, where increased mutagenesis has been suggested as a potential therapy. PMID:24713667

Sardanyés, Josep; Simó, Carles; Martínez, Regina; Solé, Ricard V; Elena, Santiago F

2014-01-01

366

Effect of Occupant and Impact Factors on Forces within Neck: I. Overview of Large Population  

NASA Astrophysics Data System (ADS)

Scientific and medical data have been gathered for nearly 500 motor-vehicle occupants, whose dynamic response[1-2] was calculated to determine the forces generated at all potential injury sites. Particular attention was paid to the load within the cervical spine to examine the influence of certain variables relating to the occupant (height, weight, sex), the impact (magnitude, direction), and the neck itself (local vector, anatomical level). Exhaustive efforts were made to match the force with each variable using linear and logarithmic fits, but correlation coefficients were generally not high. These results might be influenced by the emphasis in this research to obtain the best statistics with large groupings of patients. Hence, a separate study with more detail is proposed as a significant continuation of this effort. 1. Proper Treatment of Complex Human Structures, Announcer 27 (4), 100 (1997); 2. Physics as a Key Element in the Complete Description of Dichotomies in Injury Distribution, Bull. Am. Phys. Soc. 44, 274 (1999).

Shaibani, Saami J.

2000-03-01

367

Variability in mutational fitness effects prevents full lethal transitions in large quasispecies populations  

NASA Astrophysics Data System (ADS)

The distribution of mutational fitness effects (DMFE) is crucial to the evolutionary fate of quasispecies. In this article we analyze the effect of the DMFE on the dynamics of a large quasispecies by means of a phenotypic version of the classic Eigen's model that incorporates beneficial, neutral, deleterious, and lethal mutations. By parameterizing the model with available experimental data on the DMFE of Vesicular stomatitis virus (VSV) and Tobacco etch virus (TEV), we found that increasing mutation does not totally push the entire viral quasispecies towards deleterious or lethal regions of the phenotypic sequence space. The probability of finding regions in the parameter space of the general model that results in a quasispecies only composed by lethal phenotypes is extremely small at equilibrium and in transient times. The implications of our findings can be extended to other scenarios, such as lethal mutagenesis or genomically unstable cancer, where increased mutagenesis has been suggested as a potential therapy.

Sardanyés, Josep; Simó, Carles; Martínez, Regina; Solé, Ricard V.; Elena, Santiago F.

2014-04-01

368

Variability in mutational fitness effects prevents full lethal transitions in large quasispecies populations  

PubMed Central

The distribution of mutational fitness effects (DMFE) is crucial to the evolutionary fate of quasispecies. In this article we analyze the effect of the DMFE on the dynamics of a large quasispecies by means of a phenotypic version of the classic Eigen's model that incorporates beneficial, neutral, deleterious, and lethal mutations. By parameterizing the model with available experimental data on the DMFE of Vesicular stomatitis virus (VSV) and Tobacco etch virus (TEV), we found that increasing mutation does not totally push the entire viral quasispecies towards deleterious or lethal regions of the phenotypic sequence space. The probability of finding regions in the parameter space of the general model that results in a quasispecies only composed by lethal phenotypes is extremely small at equilibrium and in transient times. The implications of our findings can be extended to other scenarios, such as lethal mutagenesis or genomically unstable cancer, where increased mutagenesis has been suggested as a potential therapy. PMID:24713667

Sardanyés, Josep; Simó, Carles; Martínez, Regina; Solé, Ricard V.; Elena, Santiago F.

2014-01-01

369

A population of gamma-ray millisecond pulsars seen with the Fermi Large Area Telescope.  

PubMed

Pulsars are born with subsecond spin periods and slow by electromagnetic braking for several tens of millions of years, when detectable radiation ceases. A second life can occur for neutron stars in binary systems. They can acquire mass and angular momentum from their companions, to be spun up to millisecond periods and begin radiating again. We searched Fermi Large Area Telescope data for pulsations from all known millisecond pulsars (MSPs) outside of globular clusters, using rotation parameters from radio telescopes. Strong gamma-ray pulsations were detected for eight MSPs. The gamma-ray pulse profiles and spectral properties resemble those of young gamma-ray pulsars. The basic emission mechanism seems to be the same for MSPs and young pulsars, with the emission originating in regions far from the neutron star surface. PMID:19574349

Abdo, A A; Ackermann, M; Ajello, M; Atwood, W B; Axelsson, M; Baldini, L; Ballet, J; Barbiellini, G; Baring, M G; Bastieri, D; Baughman, B M; Bechtol, K; Bellazzini, R; Berenji, B; Bignami, G F; Blandford, R D; Bloom, E D; Bonamente, E; Borgland, A W; Bregeon, J; Brez, A; Brigida, M; Bruel, P; Burnett, T H; Caliandro, G A; Cameron, R A; Camilo, F; Caraveo, P A; Carlson, P; Casandjian, J M; Cecchi, C; Celik, O; Charles, E; Chekhtman, A; Cheung, C C; Chiang, J; Ciprini, S; Claus, R; Cognard, I; Cohen-Tanugi, J; Cominsky, L R; Conrad, J; Corbet, R; Cutini, S; Dermer, C D; Desvignes, G; de Angelis, A; de Luca, A; de Palma, F; Digel, S W; Dormody, M; do Couto e Silva, E; Drell, P S; Dubois, R; Dumora, D; Edmonds, Y; Farnier, C; Favuzzi, C; Fegan, S J; Focke, W B; Frailis, M; Freire, P C C; Fukazawa, Y; Funk, S; Fusco, P; Gargano, F; Gasparrini, D; Gehrels, N; Germani, S; Giebels, B; Giglietto, N; Giordano, F; Glanzman, T; Godfrey, G; Grenier, I A; Grondin, M H; Grove, J E; Guillemot, L; Guiriec, S; Hanabata, Y; Harding, A K; Hayashida, M; Hays, E; Hobbs, G; Hughes, R E; Jóhannesson, G; Johnson, A S; Johnson, R P; Johnson, T J; Johnson, W N; Johnston, S; Kamae, T; Katagiri, H; Kataoka, J; Kawai, N; Kerr, M; Knödlseder, J; Kocian, M L; Kramer, M; Kuss, M; Lande, J; Latronico, L; Lemoine-Goumard, M; Longo, F; Loparco, F; Lott, B; Lovellette, M N; Lubrano, P; Madejski, G M; Makeev, A; Manchester, R N; Marelli, M; Mazziotta, M N; McConville, W; McEnery, J E; McLaughlin, M A; Meurer, C; Michelson, P F; Mitthumsiri, W; Mizuno, T; Moiseev, A A; Monte, C; Monzani, M E; Morselli, A; Moskalenko, I V; Murgia, S; Nolan, P L; Norris, J P; Nuss, E; Ohsugi, T; Omodei, N; Orlando, E; Ormes, J F; Paneque, D; Panetta, J H; Parent, D; Pelassa, V; Pepe, M; Pesce-Rollins, M; Piron, F; Porter, T A; Rainò, S; Rando, R; Ransom, S M; Ray, P S; Razzano, M; Rea, N; Reimer, A; Reimer, O; Reposeur, T; Ritz, S; Rochester, L S; Rodriguez, A Y; Romani, R W; Roth, M; Ryde, F; Sadrozinski, H F W; Sanchez, D; Sander, A; Saz Parkinson, P M; Scargle, J D; Schalk, T L; Sgrò, C; Siskind, E J; Smith, D A; Smith, P D; Spandre, G; Spinelli, P; Stappers, B W; Starck, J L; Striani, E; Strickman, M S; Suson, D J; Tajima, H; Takahashi, H; Tanaka, T; Thayer, J B; Thayer, J G; Theureau, G; Thompson, D J; Thorsett, S E; Tibaldo, L; Torres, D F; Tosti, G; Tramacere, A; Uchiyama, Y; Usher, T L; Van Etten, A; Vasileiou, V; Venter, C; Vilchez, N; Vitale, V; Waite, A P; Wallace, E; Wang, P; Watters, K; Webb, N; Weltevrede, P; Winer, B L; Wood, K S; Ylinen, T; Ziegler, M

2009-08-14

370

Large-scale management systems and parasite populations: coccidia in rabbits.  

PubMed

Broiler rabbit production has become an important branch of animal protein and fur production, not only in the traditionally rabbit breeding and consuming countries, but recently in many other countries of the world. The profitability of the rabbit industry is dependent primarily on the good feed conversion. Aspects of this include factors such as morbidity and mortality of infections, adequate knowledge and fulfilment of both accommodation and nutritional requirements, appropriate breeding systems, etc. There is much controversy about the role of coccidia in the losses of intensified rabbit breeding enterprises. There is no doubt about the significance of Eimeria stiedai which may cause condemnation of large amounts of liver as a result of infection in rabbit colonies of small holders. However, this parasite is rare in large scale rabbit farms. In the latter, intestinal coccidiosis is most frequently--although not invariably--incriminated either as a primary or more often as a predisposing factor of intestinal enteropathies causing severe mortality, mainly in the early post-weaning period. The ability to isolate and maintain species of Eimeria in specific pathogen-free (SPF) rabbits has made it possible to characterize them, such as the most pathogenic E. intestinalis and E. flavescens: the pathogenic E. magna, E. irresidua and E. piriformis; and the least pathogenic E. perforans, E. neoleporis (syn. of E. coecicola) and E. media species. Prophylactic measures are dealt with briefly, and laboratory and field trials with the currently most promising rabbit anti-coccidial drugs (Lerbek, robenidine and salinomycin) are dealt with in more detail. PMID:6891527

Varga, I

1982-08-01

371

Anti-MDA5 Antibodies in a Large Mediterranean Population of Adults with Dermatomyositis  

PubMed Central

A new myositis-specific autoantibody directed against melanoma differentiation-associated gene 5 (anti-MDA5) has been described in patients with dermatomyositis (DM). We report the clinical characteristics of patients with anti-MDA5 in a large Mediterranean cohort of DM patients from a single center, and analyze the feasibility of detecting this autoantibody in patient sera using new assays with commercially available recombinant MDA5. The study included 117 white adult patients with DM, 15 (13%) of them classified as clinically amyopathic dermatomyositis (CADM). Clinical manifestations were analyzed, with special focus on interstitial lung disease and its severity. Determination of anti-MDA5 antibodies was performed by a new ELISA and immunoblot technique. In sera, from 14 (12%) DM patients (8 CADM), MDA5 was recognized by ELISA, and confirmed by immunoblot. Eight of the 14 anti-MDA5-positive patients (57.14%) presented rapidly-progressive interstitial lung disease (RP-ILD) versus 3 of 103 anti-MDA5-negative patients (2.91%) (P < 0.05; OR: 44.4, 95% CI 9.3–212). The cumulative survival rate was significantly lower in anti-MDA5-positive patients than in the remainder of the series (P < 0.05). Patients with anti-MDA5-associated ILD presented significantly lower 70-month cumulative survival than antisynthetase-associated ILD patients. Among the cutaneous manifestations, only panniculitis was significantly associated with the presence of anti-MDA5 antibodies (P < 0.05; OR: 3.85, 95% CI 1.11–13.27). These findings support the reliability of using commercially available recombinant MDA5 for detecting anti-MDA5 antibodies and confirm the association of these antibodies with RP-ILD in a large series of Mediterranean patients with DM. PMID:24741583

Martinez, Maria Angeles; Trallero-Araguas, Ernesto; Balada, Eva; Vilardell-Tarres, Miquel; Juárez, Cándido

2014-01-01

372

Efficient inference of population size histories and locus-specific mutation rates from large-sample genomic variation data.  

PubMed

With the recent increase in study sample sizes in human genetics, there has been growing interest in inferring historical population demography from genomic variation data. Here, we present an efficient inference method that can scale up to very large samples, with tens or hundreds of thousands of individuals. Specifically, by utilizing analytic results on the expected frequency spectrum under the coalescent and by leveraging the technique of automatic differentiation, which allows us to compute gradients exactly, we develop a very efficient algorithm to infer piecewise-exponential models of the historical effective population size from the distribution of sample allele frequencies. Our method is orders of magnitude faster than previous demographic inference methods based on the frequency spectrum. In addition to inferring demography, our method can also accurately estimate locus-specific mutation rates. We perform extensive validation of our method on simulated data and show that it can accurately infer multiple recent epochs of rapid exponential growth, a signal that is difficult to pick up with small sample sizes. Lastly, we use our method to analyze data from recent sequencing studies, including a large-sample exome-sequencing data set of tens of thousands of individuals assayed at a few hundred genic regions. PMID:25564017

Bhaskar, Anand; Wang, Y X Rachel; Song, Yun S

2015-02-01

373

Initial guess by improved population-based intelligent algorithms for large inter-frame deformation measurement using digital image correlation  

NASA Astrophysics Data System (ADS)

Digital image correlation (DIC) has received a widespread research and application in experimental mechanics. In DIC, the performance of subpixel registration algorithm (e.g., Newton-Raphson method, quasi-Newton method) relies heavily on the initial guess of deformation. In the case of small inter-frame deformation, the initial guess could be found by simple search scheme, the coarse-fine search for instance. While for large inter-frame deformation, it is difficult for simple search scheme to robustly estimate displacement parameters and deformation parameters simultaneously with low computational cost. In this paper, we proposed three improving strategies, i.e. Q-stage evolutionary strategy (T), parameter control strategy (C) and space expanding strategy (E), and then combined them into three population-based intelligent algorithms (PIAs), i.e. genetic algorithm (GA), differential evolution (DE) and particle swarm optimization (PSO), and finally derived eighteen different algorithms to calculate the initial guess for qN. The eighteen algorithms were compared in three sets of experiments including large rigid body translation, finite uniaxial strain and large rigid body rotation, and the results showed the effectiveness of proposed improving strategies. Among all compared algorithms, DE-TCE is the best which is robust, convenient and efficient for large inter-frame deformation measurement.

Zhao, Jia-qing; Zeng, Pan; Lei, Li-ping; Ma, Yuan

2012-03-01

374

Tobacco Use among Sexual Minorities  

ERIC Educational Resources Information Center

This chapter addresses tobacco use among sexual minorities. It examines research on the prevalence of tobacco use in the lesbian, gay, bisexual, and transgender (LGBT) community and discusses why tobacco use within this group continues to significantly exceed that of the general population.

Bryant, Lawrence O.; Bowman, Lorenzo

2014-01-01

375

Red Blood Cell Size Is Inversely Associated with Leukocyte Telomere Length in a Large Multi-Ethnic Population  

PubMed Central

Although mutations in the genes encoding either the protein or RNA component of telomerase have been found in patients with various blood disorders, the impact of telomere length on hematopoiesis is less well understood for subjects from the general population. Here we have measured telomere lengths of genomic DNA isolated from circulating leukocytes of 3157 subjects, ranging from 18 to 85 years of age, enrolled in a large multiethnic population based study, the Dallas Heart Study 2. Shorter telomere lengths are marginally associated with lower red blood cell counts in this cohort, but are significantly associated with larger mean red blood cell size (as measured by the MCV), increased red blood cell distribution width (RDW), higher hemoglobin levels and lower platelet counts, even after correction for age, gender and ethnicity (p-values of <0.0001, <0.0001, 0.0009 and 0.0016, respectively). In a multiple regression model we find that telomere length is a significant covariate of MCV (p?=?7.6×10?8), independent of age, ethnicity, BMI, current smoking, alcohol consumption, iron or homocysteine levels. The effect of telomere length on MCV variation is comparable to the effect of smoking or alcohol consumption and is more significant in older individuals (p?=?9.2×10?7 for >50 years vs. p?=?0.0006 for <50 years of age). To our knowledge, this is the first report of an association between telomere length and red cell size in a large urban US population and suggests a biologic mechanism for macrocytosis of aging. PMID:23226558

Kozlitina, Julia; Garcia, Christine Kim

2012-01-01

376

Detecting population declines over large areas with presence-absence, time-to-encounter, and count survey methods.  

PubMed

Ecologists often discount presence-absence surveys as a poor way to gain insight into population dynamics, in part because these surveys are not amenable to many standard statistical tests. Still, presence-absence surveys are sometimes the only feasible alternative for monitoring large areas when funds are limited, especially for sparse or difficult-to-detect species. I undertook a detailed simulation study to compare the power of presence-absence, count, and time-to-encounter surveys to detect regional declines in a population. I used a modeling approach that simulates both population numbers and the monitoring process, accounting for observation and other measurement errors. In gauging the efficacy of presence-absence surveys versus other approaches, I varied the number of survey sites, the spatial variation in encounter rate, the mean encounter rate, and the type of population loss. My results showed that presence-absence data can be as or more powerful than count data in many cases. Quantitative guidelines for choosing between presence-absence surveys and count surveys depend on the biological and logistical constraints governing a conservation monitoring situation. Generally, presence-absence surveys work best when there is little variability in abundance among the survey sites, the organism is rare, and the species is difficult to detect so that the time spent getting to each survey site is less than or equal to the time spent surveying each site. Count surveys work best otherwise. I present a case study with count data on the Northern Flicker (Colaptes auratus) from the North American Breeding Bird Survey to illustrate how the method might be used with field-survey data. The case study demonstrates that a count survey would be the most cost-effective design but would entail reduction in the number of sites. If this site reduction is not desirable, a presence-absence survey would be the most cost-effective survey. PMID:16909580

Pollock, Jacob E

2006-06-01

377

Beliefs concerning sexual health problems and treatment seeking among men in an Indian slum community  

Microsoft Academic Search

This study explores the sexual health problems and treatment-seeking behaviour of men in a Mumbai slum population. Men consider wet dreams, masturbation, early ejaculation, sexual weakness, and other semen-related issues as serious sexual health problems. Suppression of sexual desire was one of the major causes perceived by men for wet dreams, whereas masturbation was seen as the major cause for

Ravi K. Verma; Sumitra Sharma; Rajendar Singh; G. Rangaiyan; Pertti J. Pelto

2003-01-01

378

Sexuality and sickle cell anemia  

PubMed Central

Background Sickle cell disease, the most common hereditary blood disease in the world, is the result of an atypical hemoglobin called S (Hb S) which, when homozygous (Hb SS) is the cause of sickle cell anemia. Changes of puberty, correlated with a delayed growth spurt, begin late in both male and female sickle cell anemia individuals with repercussions on sexuality and reproduction. The objectives of this exploratory and descriptive study were to characterize the development of sexuality in adults with sickle cell anemia by investigating the patient's perception of their sex life, as well as the information they had and needed on this subject. Methods Twenty male and female sickle cell anemia patients treated at the Hemocentro Regional de Uberaba (UFTM) with ages between 19 and 47 years old were enrolled. A socioeconomic questionnaire and a semi-structured interview on sexuality, reproduction and genetic counseling were applied. Results This study shows that the sickle cell anemia patients lacked information on sexuality especially about the risks of pregnancy and the possible inheritance of the disease by their children. Moreover, the sexual life of the patients was impaired due to pain as well as discrimination and negative feelings experienced in close relationships. Conclusion The health care of sickle cell anemia patients should take into account not only the clinical aspects of the disease, but also psychosocial aspects by providing counseling on sexuality, reproduction and genetics, in order to give this population the possibility of a better quality of life. PMID:23741184

Côbo, Viviane de Almeida; Chapadeiro, Cibele Alves; Ribeiro, João Batista; Moraes-Souza, Helio; Martins, Paulo Roberto Juliano

2013-01-01

379

Prostitution, sexual behavior and STDs.  

PubMed

Prostitution involves the exchange of sexual services for economic compensation. As sexual behaviour is an important determinant in transmitting HIV and sexually transmitted diseases (STDs), sex workers (SWs), transgenders and clients are often labeled as a "high risk group" in the context of HIV and STDs. It has been documented that female sex workers in particular have an increased prevalence of untreated STDs and have been hypothesized to affect the health and HIV incidence of the general population. People involved in prostitution are a cause for concern from both public health and economic perspectives. However, little is known about why they remain in this type of activity given the risks prostitution presents, and even less is known about how to intervene and interrupt the complex cycle of prostitution. The aim of this paper is to provide a clinical and epidemiological analysis of the relationship between prostitution, sexual behavior and outbreaks of STDs; to assess the role that migrants, transgenders and clients of SWs have in prostitution and in the outbreaks of STDs. In addition, we also want to highlight how new sexual networks, like the Internet, have become an increasingly important vehicle to sharing information about prostitution, sexual behavior and STDs. Finally we present what may be the prevention strategies and the goals in order to stem the spread of STDs among these hard-to-access groups. PMID:23007210

Gaspari, V; D'Antuono, A; Bellavista, S; Trimarco, R; Patrizi, A

2012-08-01

380

The effect of purging on sexually selected traits through antagonistic pleiotropy with survival  

PubMed Central

Sexually selected traits are expected to evolve to a point where their positive effect on reproductive success is counterbalanced by their negative effect on survival. At the genetic level, such a trade-off implies antagonistic pleiotropy between survival and the expression of sexually selected traits. Yet, the consequences of such a genetic architecture have been largely overlooked in studies examining how inbreeding influences sexually selected traits. These studies have solely interpreted their results as an effect of increased homozygosity. An alternative, however, is that purging of recessive alleles deleterious for survival when inbreeding increases can negatively affect the expression of sexually selected traits through antagonistic pleiotropy. We tested this hypothesis by analyzing the effects of inbreeding on several male ornaments and life-history traits across 20 captive populations of guppies (Poecilia reticulata) with varying levels of inbreeding. Only one ornament, orange area, decreased in its expression with an increasing level of inbreeding. This was most likely due to purging because we found no within-population relationship between orange area and the inbreeding coefficient. We further tested this hypothesis by crossing unrelated individuals from the four most inbred populations, creating a group of individuals with purged genomes but restored heterozygosity. Restoration of heterozygosity only slightly increased orange area, confirming that the decrease in orange area in the inbred populations most likely resulted from purging. These results support previous studies suggesting the existence of antagonistic pleiotropy between ornament expression and survival. PMID:22833793

Bolstad, Geir H; Pélabon, Christophe; Larsen, Line-K; Fleming, Ian A; Viken, Åslaug; Rosenqvist, Gunilla

2012-01-01

381

THE MAGELLANIC MOPRA ASSESSMENT (MAGMA). I. THE MOLECULAR CLOUD POPULATION OF THE LARGE MAGELLANIC CLOUD  

SciTech Connect

We present the properties of an extensive sample of molecular clouds in the Large Magellanic Cloud (LMC) mapped at 11 pc resolution in the CO(1-0) line. Targets were chosen based on a limiting CO flux and peak brightness as measured by the NANTEN survey. The observations were conducted with the ATNF Mopra Telescope as part of the Magellanic Mopra Assessment. We identify clouds as regions of connected CO emission and find that the distributions of cloud sizes, fluxes, and masses are sensitive to the choice of decomposition parameters. In all cases, however, the luminosity function of CO clouds is steeper than dN/dL{proportional_to}L{sup -2}, suggesting that a substantial fraction of mass is in low-mass clouds. A correlation between size and linewidth, while apparent for the largest emission structures, breaks down when those structures are decomposed into smaller structures. We argue that the correlation between virial mass and CO luminosity is the result of comparing two covariant quantities, with the correlation appearing tighter on larger scales where a size-linewidth relation holds. The virial parameter (the ratio of a cloud's kinetic to self-gravitational energy) shows a wide range of values and exhibits no clear trends with the CO luminosity or the likelihood of hosting young stellar object (YSO) candidates, casting further doubt on the assumption of virialization for molecular clouds in the LMC. Higher CO luminosity increases the likelihood of a cloud harboring a YSO candidate, and more luminous YSOs are more likely to be coincident with detectable CO emission, confirming the close link between giant molecular clouds and massive star formation.

Wong, Tony; Chu, You-Hua; Gruendl, Robert A.; Looney, Leslie W.; Seale, Jonathan; Welty, Daniel E. [Astronomy Department, University of Illinois, Urbana, IL 61801 (United States); Hughes, Annie; Maddison, Sarah [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, VIC 3122 (Australia); Ott, Juergen [National Radio Astronomy Observatory, P.O. Box O, 1003 Lopezville Road, Socorro, NM 87801 (United States); Muller, Erik; Fukui, Yasuo; Kawamura, Akiko; Mizuno, Yoji [Department of Astrophysics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan); Pineda, Jorge L. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109-8099 (United States); Bernard, Jean-Philippe; Paradis, Deborah [CNRS, IRAP, 9 Av. Colonel Roche, BP 44346, F-31028 Toulouse cedex 4 (France); Henkel, Christian [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany); Klein, Ulrich, E-mail: wongt@astro.illinois.edu [Argelander Institut fuer Astronomie, Universitaet Bonn, Auf dem Huegel 71, D-53121 Bonn (Germany)

2011-12-01

382

Sexual Complaints, Pelvic Floor Symptoms, and Sexual Distress in Women over Forty  

PubMed Central

Introduction The American Psychiatric Association recommends considering sexually related personal distress when assessing female sexual dysfunction. Currently, there is little data regarding the impact of sexual complaints on sexual distress. Aim To investigate the association between sexual complaints and perceived sexual distress in a population of ambulatory adult women. Methods Using the short forms of the Personal Experiences Questionnaire and Pelvic Organ Prolapse/Urinary Incontinence Sexual Function Questionnaire, we assessed sexual complaints among 305 women seeking outpatient gynecologic care. Depressive symptoms were quantified using the Center for Epidemiologic Studies Depression (CESD) score. Sexual distress was measured using the Female Sexual Distress Scale (FSDS). Using multivariable logistic regression, we compared sexual complaints between distressed and nondistressed women. Main Outcome Measures Sexual distress, defined by FSDS score ?15. Results FSDS scores were available for 292/305 participants. Seventy-six (26%) scores reflected distress. Distressed women were more likely to be younger (55.2 ± 1.0 years vs. 56.7 ± 0.8 years, P = 0.017); have higher CESD scores (16.6 vs. 9.5, P = 0.001); and report decreased arousal (56.8% vs. 25.1%, P = 0.001), infrequent orgasm (54% vs. 28.8%, P = 0.001), and dyspareunia (39.7% vs. 10.6%, P = 0.001). Women with sexual distress were also more likely to report sexual difficulty related to pelvic floor symptoms, including urinary incontinence with sexual activity (9% vs. 1.3%, P = 0.005), sexual avoidance due to vaginal prolapse (13.9% vs. 1%, P = 0.001), or sexual activity restriction due to fear of urinary incontinence (14.9% vs. 0.5%, P = 0.001). After multivariate analysis, sexual distress was significantly associated with dyspareunia (odds ratio [OR] 3.11, P = 0.008) and depression score (OR 1.05, P = 0.006), and inversely associated with feelings of arousal during sex (OR 0.19, P = 0.001). Conclusion Our results indicate that sexually related personal distress is significantly associated with dyspareunia, depressive symptoms, and decreased arousal during sexual activity. This contributes to our understanding of how sexual complaints may adversely affect women’s quality of life. PMID:20704643

Knoepp, Leise R.; Shippey, Stuart H.; Chen, Chi Chiung Grace; Cundiff, Geoffrey W.; Derogatis, Leonard R.; Handa, Victoria L.

2011-01-01

383

Sexual Esteem in Emerging Adulthood: Associations with Sexual Behavior, Contraception Use, and Romantic Relationships.  

PubMed

Sexual esteem is an integral psychological aspect of sexual health (Snell & Papini, 1989 ), yet it is unclear whether sexual esteem is associated with sexual health behavior among heterosexual men and women. The current analysis used a normative framework for sexual development (Lefkowitz & Gillen, 2006 ; Tolman & McClelland, 2011 ) by examining the association of sexual esteem with sexual behavior, contraception use, and romantic relationship characteristics. Participants (N = 518; 56.0% female; mean age = 20.43 years; 26.8% identified as Hispanic/Latino; among non-Hispanic/Latinos, 27.2% of the full sample identified as European American, 22.4% Asian American, 14.9% African American, and 8.7% multiracial) completed Web-based surveys at a large Northeastern university. Participants who had oral sex more frequently, recently had more oral and penetrative sex partners (particularly for male participants), and spent more college semesters in romantic relationships tended to have higher sexual esteem than those who had sex less frequently, with fewer partners, or spent more semesters without romantic partners. Sexually active male emerging adults who never used contraception during recent penetrative sex tended to have higher sexual esteem than those who did use it, whereas female emerging adults who never used contraception tended to have lower sexual esteem than those who did use it. Implications of these results for the development of a healthy sexual self-concept in emerging adulthood are discussed. PMID:25210789

Maas, Megan K; Lefkowitz, Eva S

2014-09-11

384

Get SMART: Effective Treatment for Sexually Abused Children with Problematic Sexual Behavior  

Microsoft Academic Search

Nearly 20% of children with a history of sexual abuse develop problematic sexual behaviors (PSBs). Effective mental health treatments for this specialized population are limited. This article presents outcome data on 62 children enrolled in the preliminary trial of the Safety, Mentoring, Advocacy, Recovery, and Treatment (SMART) model. SMART integrates individual, family, and group therapy in a strengths-based, problem-focused treatment

Betsy J. Offermann; Elizabeth Johnson; Sonja T. Johnson-Brooks; Harolyn M. E. Belcher

2008-01-01

385

Addressing Sexually Transmitted Infections (STIs), including HIV\\/AIDS, in the Context of Sexual Health  

Microsoft Academic Search

Sexually transmitted infections (STIs) have occupied a central place in public health agendas for at least the past 500 years, but have been the subject of opinions, decrees and “moral positions” for much longer. Societies have long tried to control the sexual behaviors of their populations, not only for reasons of social control, but also with the objective of controlling

Sarah Hawkes

2008-01-01

386

Gay/Lesbian sexual orientation increases risk for cigarette smoking and heavy drinking among members of a large Northern California health plan  

PubMed Central

Background and significance Tobacco and alcohol use and related morbidity and mortality are critical public health problems. Results of several, but not all, studies suggest that lesbians and gay men are at elevated risk for smoking tobacco and alcohol misuse. Methods Data from random sample general health surveys of adult members of a large Northern California Health Plan conducted in 1999 and 2002 were analyzed using gender-based multivariate logistic regression models to assess whether lesbians (n = 210) and gay men (n = 331) aged 20–65 were more likely than similarly aged heterosexual women (n = 12,188) and men (n = 9342) to be smokers and heavy drinkers. Results After adjusting for age, race/ethnicity, education, and survey year, lesbians were significantly more likely than heterosexual women to be heavy drinkers (OR 2.14, 95% CI 1.08, 4.23) and current smokers (OR 1.60, 95% CI 1.02, 2.51). Among men, gays were significantly more likely than heterosexuals to be current smokers (OR 2.40, 95% CI 1.75, 3.30), with borderline significant increased risk for heavy drinking (OR 1.54, 95% CI 0.96, 2.45). Conclusion Lesbians and gay men may be at increased risk for morbidity and mortality due to higher levels of cigarette and alcohol use. More population-based research is needed to understand the nature of substance use in these communities so that appropriate interventions can be developed. PMID:17018152

Gruskin, Elisabeth P; Gordon, Nancy

2006-01-01

387

An analysis of continent-wide patterns of sexual selection in a passerine bird.  

PubMed

Patterns of selection are widely believed to differ geographically, causing adaptation to local environmental conditions. However, few studies have investigated patterns of phenotypic selection across large spatial scales. We quantified the intensity of selection on morphology in a monogamous passerine bird, the barn swallow Hirundo rustica, using 6495 adults from 22 populations distributed across Europe and North Africa. According to the classical Darwin-Fisher mechanism of sexual selection in monogamous species, two important components of fitness due to sexual selection are the advantages that the most attractive males acquire by starting to breed early and their high annual fecundity. We estimated directional selection differentials on tail length (a secondary sexual character) and directional selection gradients after controlling for correlated selection on wing length and tarsus length with respect to these two fitness components. Phenotype and fitness components differed significantly among populations for which estimates were available for more than a single year. Likewise, selection differentials and selection gradients differed significantly among populations for tail length, but not for the other two characters. Sexual selection differentials differed significantly from zero across populations for tail length, particularly in males. Controlling statistically for the effects of age reduced the intensity of selection by 60 to 81%, although corrected and uncorrected estimates were strongly positively correlated. Selection differentials and gradients for tail length were positively correlated between the sexes among populations for selection acting on breeding date, but not for fecundity selection. The intensity of selection with respect to breeding date and fecundity were significantly correlated for tail length across populations. Sexual size dimorphism in tail length was significantly correlated with selection differentials with respect to breeding date for tail length in male barn swallows across populations. These findings suggest that patterns of sexual selection are consistent across large geographical scales, but also that they vary among populations. In addition, geographical patterns of phenotypic selection predict current patterns of phenotypic variation among populations, suggesting that consistent patterns of selection have been present for considerable amounts of time. PMID:16739465

Møller, A P; Chabi, Y; Cuervo, J J; De Lope, F; Kilpimaa, J; Kose, M; Matyjasiak, P; Pap, P L; Saino, N; Sakraoui, R; Schifferli, L; von Hirschheydt, J

2006-04-01

388

Human preferences for sexually dimorphic faces may be evolutionarily novel.  

PubMed

A large literature proposes that preferences for exaggerated sex typicality in human faces (masculinity/femininity) reflect a long evolutionary history of sexual and social selection. This proposal implies that dimorphism was important to judgments of attractiveness and personality in ancestral environments. It is difficult to evaluate, however, because most available data come from large-scale, industrialized, urban populations. Here, we report the results for 12 populations with very diverse levels of economic development. Surprisingly, preferences for exaggerated sex-specific traits are only found in the novel, highly developed environments. Similarly, perceptions that masculine males look aggressive increase strongly with development and, specifically, urbanization. These data challenge the hypothesis that facial dimorphism was an important ancestral signal of heritable mate value. One possibility is that highly developed environments provide novel opportunities to discern relationships between facial traits and behavior by exposing individuals to large numbers of unfamiliar faces, revealing patterns too subtle to detect with smaller samples. PMID:25246593

Scott, Isabel M; Clark, Andrew P; Josephson, Steven C; Boyette, Adam H; Cuthill, Innes C; Fried, Ruby L; Gibson, Mhairi A; Hewlett, Barry S; Jamieson, Mark; Jankowiak, William; Honey, P Lynne; Huang, Zejun; Liebert, Melissa A; Purzycki, Benjamin G; Shaver, John H; Snodgrass, J Josh; Sosis, Richard; Sugiyama, Lawrence S; Swami, Viren; Yu, Douglas W; Zhao, Yangke; Penton-Voak, Ian S

2014-10-01

389

Human preferences for sexually dimorphic faces may be evolutionarily novel  

PubMed Central

A large literature proposes that preferences for exaggerated sex typicality in human faces (masculinity/femininity) reflect a long evolutionary history of sexual and social selection. This proposal implies that dimorphism was important to judgments of attractiveness and personality in ancestral environments. It is difficult to evaluate, however, because most available data come from large-scale, industrialized, urban populations. Here, we report the results for 12 populations with very diverse levels of economic development. Surprisingly, preferences for exaggerated sex-specific traits are only found in the novel, highly developed environments. Similarly, perceptions that masculine males look aggressive increase strongly with development and, specifically, urbanization. These data challenge the hypothesis that facial dimorphism was an important ancestral signal of heritable mate value. One possibility is that highly developed environments provide novel opportunities to discern relationships between facial traits and behavior by exposing individuals to large numbers of unfamiliar faces, revealing patterns too subtle to detect with smaller samples. PMID:25246593

Scott, Isabel M.; Clark, Andrew P.; Josephson, Steven C.; Boyette, Adam H.; Cuthill, Innes C.; Fried, Ruby L.; Gibson, Mhairi A.; Hewlett, Barry S.; Jamieson, Mark; Jankowiak, William; Honey, P. Lynne; Huang, Zejun; Liebert, Melissa A.; Purzycki, Benjamin G.; Shaver, John H.; Snodgrass, J. Josh; Sosis, Richard; Sugiyama, Lawrence S.; Swami, Viren; Yu, Douglas W.; Zhao, Yangke; Penton-Voak, Ian S.

2014-01-01

390

Father-offspring phenotypic correlations suggest intralocus sexual conflict for a fitness-linked trait in a wild sexually dimorphic mammal.  

PubMed

In sexually dimorphic and polygynous mammals, sexual selection often favours large males with well-developed weaponry, as these secondary sexual characters confer advantages in intrasexual competition and are often preferred by females. Little is known, however, about the effects of sexually selected paternal traits on offspring phenotype in wild mammals, especially when considering that shared phenotypic traits and selection can also differ greatly between genders. Here, we conducted molecular parentage analyses in a long-term study population of mountain goats (Oreamnos americanus), an ungulate exhibiting high sexual dimorphism in mass, to first assess the determinants of yearly reproductive success (YRS) in males. We then examined the effects of paternal characteristics on offspring mass at 1 year of age. Paternity was highly skewed, with 9 per cent of 57 males siring 51 per cent of 96 offspring assigned over 12 years. Male YRS increased with age until apparent reproductive senescence at 9 years, but mass was a stronger determinant of siring success than age, horn length or social rank. Mass of sons increased with paternal mass, but the mass of daughters was negatively related to that of their father, a finding consistent with recent theory on intralocus sexual conflict. Because early differences in mass persisted to early adulthood, sex-specific effects of paternal mass can have important fitness consequences, as adult mass is positively linked with reproduction in both sexes. Divergent father-offspring phenotypic correlations may partly explain the maintenance of sexual dimorphism in mountain goats and the large variance observed for this homologous trait within each gender in polygynous mammals. PMID:19740880

Mainguy, Julien; Côté, Steeve D; Festa-Bianchet, Marco; Coltman, David W

2009-11-22

391

Father–offspring phenotypic correlations suggest intralocus sexual conflict for a fitness-linked trait in a wild sexually dimorphic mammal  

PubMed Central

In sexually dimorphic and polygynous mammals, sexual selection often favours large males with well-developed weaponry, as these secondary sexual characters confer advantages in intrasexual competition and are often preferred by females. Little is known, however, about the effects of sexually selected paternal traits on offspring phenotype in wild mammals, especially when considering that shared phenotypic traits and selection can also differ greatly between genders. Here, we conducted molecular parentage analyses in a long-term study population of mountain goats (Oreamnos americanus), an ungulate exhibiting high sexual dimorphism in mass, to first assess the determinants of yearly reproductive success (YRS) in males. We then examined the effects of paternal characteristics on offspring mass at 1 year of age. Paternity was highly skewed, with 9 per cent of 57 males siring 51 per cent of 96 offspring assigned over 12 years. Male YRS increased with age until apparent reproductive senescence at 9 years, but mass was a stronger determinant of siring success than age, horn length or social rank. Mass of sons increased with paternal mass, but the mass of daughters was negatively related to that of their father, a finding consistent with recent theory on intralocus sexual conflict. Because early differences in mass persisted to early adulthood, sex-specific effects of paternal mass can have important fitness consequences, as adult mass is positively linked with reproduction in both sexes. Divergent father–offspring phenotypic correlations may partly explain the maintenance of sexual dimorphism in mountain goats and the large variance observed for this homologous trait within each gender in polygynous mammals. PMID:19740880

Mainguy, Julien; Côté, Steeve D.; Festa-Bianchet, Marco; Coltman, David W.

2009-01-01

392

Sexual Intimacy After Sexual Assault or Sexual Abuse1  

E-print Network

with others for some time. Fortunately, even if one does not actively work on sexual healing, as the sexual or maintaining an intimate relationship 9. Experiencing vaginal pain or orgasmic difficulties 10.Experiencing concerns at this time, and it will indicate to you how the sexual assault or abuse may have impacted your

Machel, Hans

393

Sexual Dysfunction and Infertility  

MedlinePLUS

... asrm.org PATIENT FACT SHEET Sexual Dysfunction and Infertility You probably don't realize how many people ... talk to a sex therapist. Sexual dysfunction and infertility Sexual dysfunction may cause problems getting pregnant (infertility). ...

394

Your Sexual Health  

MedlinePLUS

... during treatment of a sexual problem? • Glossary Your Sexual Health 4. Sexual pain disorder What are desire problems? ... by women. A lack of desire before having sex is normal for some women. They may not ...

395

Understanding Sexual Violence  

MedlinePLUS

... risky sexual activity. Why is sexual violence a public health problem? SV is a significant problem in the ... CDC uses a 4-step approach to address public health problems like sexual violence. Step 1: Define the ...

396

Sexual selection drives speciation in an Amazonian frog  

E-print Network

demonstrated premating isolation among populations of green-eyed tree frogs, Litoria genimaculataSexual selection drives speciation in an Amazonian frog Kathryn E. Boul1, , W. Chris Funk1 populations of an Amazonian frog (Physalaemus petersi ). First, sexual selection has promoted divergence

397

Association of Osteoarthritis With Serum Levels of the Environmental Contaminants Perfluorooctanoate and Perfluorooctane Sulfonate in a Large Appalachian Population  

PubMed Central

Perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) are persistent environmental contaminants that affect metabolic regulation, inflammation, and other factors implicated in the pathogenesis of osteoarthritis (OA). However, the link between these compounds and OA remains unknown. In this study, the authors investigated the association of OA with PFOA and PFOS in a population of 49,432 adults from 6 PFOA-contaminated water districts in the mid-Ohio Valley (2005–2006). Participants completed a comprehensive health survey; serum levels of PFOA, PFOS, and a range of other blood markers were also measured. Medical history, including physician diagnosis of osteoarthritis, was assessed via self-report. Analyses included adjustment for demographic and lifestyle characteristics, body mass index, and other potential confounders. Reported OA showed a significant positive association with PFOA serum levels (for highest quartile of PFOA vs. lowest, adjusted odds ratio = 1.3, 95% confidence interval: 1.2, 1.5; P-trend = 0.00001) and a significant inverse association with PFOS (for highest quartile vs. lowest, adjusted odds ratio = 0.8, 95% confidence interval: 0.7, 0.9; P-trend = 0.00005). The relation between PFOA and OA was significantly stronger in younger and nonobese adults. Although the cross-sectional nature of this large, population-based study limits causal inference, the observed strong, divergent associations of reported OA with PFOA and PFOS may have important public health and etiologic implications and warrant further investigation. PMID:21709135

Innes, Kim E.; Ducatman, Alan M.; Luster, Michael I.; Shankar, Anoop

2011-01-01

398

Association of osteoarthritis with serum levels of the environmental contaminants perfluorooctanoate and perfluorooctane sulfonate in a large Appalachian population.  

PubMed

Perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) are persistent environmental contaminants that affect metabolic regulation, inflammation, and other factors implicated in the pathogenesis of osteoarthritis (OA). However, the link between these compounds and OA remains unknown. In this study, the authors investigated the association of OA with PFOA and PFOS in a population of 49,432 adults from 6 PFOA-contaminated water districts in the mid-Ohio Valley (2005-2006). Participants completed a comprehensive health survey; serum levels of PFOA, PFOS, and a range of other blood markers were also measured. Medical history, including physician diagnosis of osteoarthritis, was assessed via self-report. Analyses included adjustment for demographic and lifestyle characteristics, body mass index, and other potential confounders. Reported OA showed a significant positive association with PFOA serum levels (for highest quartile of PFOA vs. lowest, adjusted odds ratio = 1.3, 95% confidence interval: 1.2, 1.5; P-trend = 0.00001) and a significant inverse association with PFOS (for highest quartile vs. lowest, adjusted odds ratio = 0.8, 95% confidence interval: 0.7, 0.9; P-trend = 0.00005). The relation between PFOA and OA was significantly stronger in younger and nonobese adults. Although the cross-sectional nature of this large, population-based study limits causal inference, the observed strong, divergent associations of reported OA with PFOA and PFOS may have important public health and etiologic implications and warrant further investigation. PMID:21709135

Innes, Kim E; Ducatman, Alan M; Luster, Michael I; Shankar, Anoop

2011-08-15

399

CONSTRAINTS ON THE GALACTIC POPULATION OF TeV PULSAR WIND NEBULAE USING FERMI LARGE AREA TELESCOPE OBSERVATIONS  

SciTech Connect

Pulsar wind nebulae (PWNe) have been established as the most populous class of TeV {gamma}-ray emitters. Since launch, the Fermi Large Area Telescope (LAT) has identified five high-energy (100 MeV < E < 100 GeV) {gamma}-ray sources as PWNe and detected a large number of PWN candidates, all powered by young and energetic pulsars. The wealth of multi-wavelength data available and the new results provided by Fermi-LAT give us an opportunity to find new PWNe and to explore the radiative processes taking place in known ones. The TeV {gamma}-ray unidentified (UNID) sources are the best candidates for finding new PWNe. Using 45 months of Fermi-LAT data for energies above 10 GeV, an analysis was performed near the position of 58 TeV PWNe and UNIDs within 5 Degree-Sign of the Galactic plane to establish new constraints on PWN properties and find new clues on the nature of UNIDs. Of the 58 sources, 30 were detected, and this work provides their {gamma}-ray fluxes for energies above 10 GeV. The spectral energy distributions and upper limits, in the multi-wavelength context, also provide new information on the source nature and can help distinguish between emission scenarios, i.e., between classification as a pulsar candidate or as a PWN candidate. Six new GeV PWN candidates are described in detail and compared with existing models. A population study of GeV PWN candidates as a function of the pulsar/PWN system characteristics is presented.

Acero, F.; Brandt, T. J. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Ackermann, M. [Deutsches Elektronen Synchrotron DESY, D-15738 Zeuthen (Germany); Ajello, M. [Space Sciences Laboratory, University of California, 7 Gauss Way, Berkeley, CA 94720-7450 (United States); Allafort, A.; Bechtol, K.; Blandford, R. D.; Bloom, E. D.; Bottacini, E.; Buehler, R. [W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States); Baldini, L. [Universita di Pisa and Istituto Nazionale di Fisica Nucleare, Sezione di Pisa, I-56127 Pisa (Italy); Ballet, J. [Laboratoire AIM, CEA-IRFU/CNRS/Universite Paris Diderot, Service d'Astrophysique, CEA Saclay, F-91191 Gif sur Yvette (France); Barbiellini, G. [Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, I-34127 Trieste (Italy); Bastieri, D.; Buson, S. [Istituto Nazionale di Fisica Nucleare, Sezione di Padova, I-35131 Padova (Italy); Bellazzini, R.; Bregeon, J. [Istituto Nazionale di Fisica Nucleare, Sezione di Pisa, I-56127 Pisa (Italy); Bonamente, E. [Istituto Nazionale di Fisica Nucleare, Sezione di Perugia, I-06123 Perugia (Italy); Brigida, M. [Dipartimento di Fisica ''M. Merlin'' dell'Universita e del Politecnico di Bari, I-70126 Bari (Italy); Bruel, P., E-mail: funk@slac.stanford.edu, E-mail: joshualande@gmail.com, E-mail: lemoine@cenbg.in2p3.fr, E-mail: rousseau@cenbg.in2p3.fr [Laboratoire Leprince-Ringuet, Ecole polytechnique, CNRS/IN2P3, F-91128 Palaiseau (France); and others

2013-08-10

400

The earnings effects of sexual orientation  

Microsoft Academic Search

This investigation of the effect of sexual orientation on earnings employs General Social Survey data from 1989-96. Depending largely on the definition of sexual orientation used, earnings are estimated as having been between 14% and 16% lower for gay men than for heterosexual men, and between 20% and 34% higher for lesbian women than for heterosexual women. This evidence, the

Dan A. Black; Hoda R. Makar; Seth G. Sanders; Lowell J. Taylor

2003-01-01

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