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Sample records for sexually reproducing species

  1. Elastic, not plastic species: Frozen plasticity theory and the origin of adaptive evolution in sexually reproducing organisms

    PubMed Central

    2010-01-01

    Background Darwin's evolutionary theory could easily explain the evolution of adaptive traits (organs and behavioral patterns) in asexual but not in sexual organisms. Two models, the selfish gene theory and frozen plasticity theory were suggested to explain evolution of adaptive traits in sexual organisms in past 30 years. Results The frozen plasticity theory suggests that sexual species can evolve new adaptations only when their members are genetically uniform, i.e. only after a portion of the population of the original species had split off, balanced on the edge of extinction for several generations, and then undergone rapid expansion. After a short period of time, estimated on the basis of paleontological data to correspond to 1-2% of the duration of the species, polymorphism accumulates in the gene pool due to frequency-dependent selection; and thus, in each generation, new mutations occur in the presence of different alleles and therefore change their selection coefficients from generation to generation. The species ceases to behave in an evolutionarily plastic manner and becomes evolutionarily elastic on a microevolutionary time-scale and evolutionarily frozen on a macroevolutionary time-scale. It then exists in this state until such changes accumulate in the environment that the species becomes extinct. Conclusion Frozen plasticity theory, which includes the Darwinian model of evolution as a special case - the evolution of species in a plastic state, not only offers plenty of new predictions to be tested, but also provides explanations for a much broader spectrum of known biological phenomena than classic evolutionary theories. Reviewers This article was reviewed by Rob Knight, Fyodor Kondrashov and Massimo Di Giulio (nominated by David H. Ardell). PMID:20067646

  2. Host-associated differentiation in a highly polyphagous, sexually reproducing insect herbivore

    PubMed Central

    Antwi, Josephine B; Sword, Gregory A; Medina, Raul F

    2015-01-01

    Insect herbivores may undergo genetic divergence on their host plants through host-associated differentiation (HAD). Much of what we know about HAD involves insect species with narrow host ranges (i.e., specialists) that spend part or all their life cycle inside their hosts, and/or reproduce asexually (e.g., parthenogenetic insects), all of which are thought to facilitate HAD. However, sexually reproducing polyphagous insects can also exhibit HAD. Few sexually reproducing insects have been tested for HAD, and when they have insects from only a handful of potential host-plant populations have been tested, making it difficult to predict how common HAD is when one considers the entire species’ host range. This question is particularly relevant when considering insect pests, as host-associated populations may differ in traits relevant to their control. Here, we tested for HAD in a cotton (Gossypium hirsutum) pest, the cotton fleahopper (CFH) (Pseudatomoscelis seriatus), a sexually reproducing, highly polyphagous hemipteran insect. A previous study detected one incidence of HAD among three of its host plants. We used Amplified fragment length polymorphism (AFLP) markers to assess HAD in CFH collected from an expanded array of 13 host-plant species belonging to seven families. Overall, four genetically distinct populations were found. One genetically distinct genotype was exclusively associated with one of the host-plant species while the other three were observed across more than one host-plant species. The relatively low degree of HAD in CFH compared to the pea aphid, another hemipteran insect, stresses the likely importance of sexual recombination as a factor increasing the likelihood of HAD. PMID:26257868

  3. Mate-Finding as an Overlooked Critical Determinant of Dispersal Variation in Sexually-Reproducing Animals

    PubMed Central

    Gilroy, James J.; Lockwood, Julie L.

    2012-01-01

    Dispersal is a critically important process in ecology, but robust predictive models of animal dispersal remain elusive. We identify a potentially ubiquitous component of variation in animal dispersal that has been largely overlooked until now: the influence of mate encounters on settlement probability. We use an individual-based model to simulate dispersal in sexually-reproducing organisms that follow a simple set of movement rules based on conspecific encounters, within an environment lacking spatial habitat heterogeneity. We show that dispersal distances vary dramatically with fluctuations in population density in such a model, even in the absence of variation in dispersive traits between individuals. In a simple random-walk model with promiscuous mating, dispersal distributions become increasingly ‘fat-tailed’ at low population densities due to the increasing scarcity of mates. Similar variation arises in models incorporating territoriality. In a model with polygynous mating, we show that patterns of sex-biased dispersal can even be reversed across a gradient of population density, despite underlying dispersal mechanisms remaining unchanged. We show that some widespread dispersal patterns found in nature (e.g. fat tailed distributions) can arise as a result of demographic variability in the absence of heterogeneity in dispersive traits across the population. This implies that models in which individual dispersal distances are considered to be fixed traits might be unrealistic, as dispersal distances vary widely under a single dispersal mechanism when settlement is influenced by mate encounters. Mechanistic models offer a promising means of advancing our understanding of dispersal in sexually-reproducing organisms. PMID:22662269

  4. Morphological and molecular characterization of a sexually reproducing colony of the booklouse Liposcelis bostrychophila (Psocodea: Liposcelididae) found in Arizona

    PubMed Central

    Yang, Qianqian; Ku?erová, Zuzana; Perlman, Steve J.; Opit, George P.; Mockford, Edward L.; Behar, Adi; Robinson, Wyatt E.; Stejskal, Václav; Li, Zhihong; Shao, Renfu

    2015-01-01

    The booklouse, Liposcelis bostrychophila, is a worldwide pest of stored products. For decades, only thelytokous parthenogenetic reproduction was documented in L. bostrychophila. Male L. bostrychophila were first found in Hawaii in 2002. In 2009, a sexual strain was found in Arizona. We examined the morphology of both males and females of the Arizona strain and compared the Arizona sexual strain with the Hawaii sexual strain and the parthenogenetic strains of L. bostrychophila. The sexual and parthenogenetic strains show some differences in eye morphology. To examine the relationship between sexual and asexual lineages, we sequenced the mitochondrial 12S and 16S ribosomal RNA genes of males and females from the Arizona strain. Phylogenetic analyses of L. bostrychophila individuals revealed that: 1) the sexually reproducing colony found in Arizona contains two closely related mitochondrial DNA haplotypes – one present in only females and the other in both males and females; and 2) the Arizona sexual strain was most closely related to a parthenogenetic strain in Illinois. We detected Rickettsia in all of the parthenogenetic individuals we checked but not in any Arizona sexual individuals. Further evidence is required to establish whether the presence of Rickettsia is linked to asexual reproduction in Liposcelis. PMID:26013922

  5. Morphological and molecular characterization of a sexually reproducing colony of the booklouse Liposcelis bostrychophila (Psocodea: Liposcelididae) found in Arizona.

    PubMed

    Yang, Qianqian; Ku?erová, Zuzana; Perlman, Steve J; Opit, George P; Mockford, Edward L; Behar, Adi; Robinson, Wyatt E; Stejskal, Václav; Li, Zhihong; Shao, Renfu

    2015-01-01

    The booklouse, Liposcelis bostrychophila, is a worldwide pest of stored products. For decades, only thelytokous parthenogenetic reproduction was documented in L. bostrychophila. Male L. bostrychophila were first found in Hawaii in 2002. In 2009, a sexual strain was found in Arizona. We examined the morphology of both males and females of the Arizona strain and compared the Arizona sexual strain with the Hawaii sexual strain and the parthenogenetic strains of L. bostrychophila. The sexual and parthenogenetic strains show some differences in eye morphology. To examine the relationship between sexual and asexual lineages, we sequenced the mitochondrial 12S and 16S ribosomal RNA genes of males and females from the Arizona strain. Phylogenetic analyses of L. bostrychophila individuals revealed that: 1) the sexually reproducing colony found in Arizona contains two closely related mitochondrial DNA haplotypes--one present in only females and the other in both males and females; and 2) the Arizona sexual strain was most closely related to a parthenogenetic strain in Illinois. We detected Rickettsia in all of the parthenogenetic individuals we checked but not in any Arizona sexual individuals. Further evidence is required to establish whether the presence of Rickettsia is linked to asexual reproduction in Liposcelis. PMID:26013922

  6. Analysis of polymorphisms in milk proteins from cloned and sexually reproduced goats.

    PubMed

    Xing, H; Shao, B; Gu, Y Y; Yuan, Y G; Zhang, T; Zang, J; Cheng, Y

    2015-01-01

    This study evaluates the relationship between the genotype and milk protein components in goats. Milk samples were collected from cloned goats and normal white goats during different postpartum (or abortion) phases. Two cloned goats, originated from the same somatic line of goat mammary gland epithelial cells, and three sexually reproduced normal white goats with no genetic relationships were used as the control. The goats were phylogenetically analyzed by polymerase chain reaction-restriction fragment length polymorphism. The milk protein components were identified by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The results indicated that despite the genetic fingerprints being identical, the milk protein composition differed between the two cloned goats. The casein content of cloned goat C-50 was significantly higher than that of cloned goat C-4. Conversely, although the genetic fingerprints of the normal white goats N-1, N-2, and N-3 were not identical, the milk protein profiles did not differ significantly in their milk samples (obtained on postpartum day 15, 20, 25, 30, and 150). These results indicated an association between milk protein phenotypes and genetic polymorphisms, epigenetic regulation, and/or non-chromosomal factors. This study extends the knowledge of goat milk protein polymorphisms, and provides new strategies for the breeding of high milk-yielding goats. PMID:26662412

  7. Simultaneous Mendelian and clonal genome transmission in a sexually reproducing, all-triploid vertebrate

    PubMed Central

    Stöck, Matthias; Ustinova, Jana; Betto-Colliard, Caroline; Schartl, Manfred; Moritz, Craig; Perrin, Nicolas

    2012-01-01

    Meiosis in triploids faces the seemingly insuperable difficulty of dividing an odd number of chromosome sets by two. Triploid vertebrates usually circumvent this problem through either asexuality or some forms of hybridogenesis, including meiotic hybridogenesis that involve a reproductive community of different ploidy levels and genome composition. Batura toads (Bufo baturae; 3n = 33 chromosomes), however, present an all-triploid sexual reproduction. This hybrid species has two genome copies carrying a nucleolus-organizing region (NOR+) on chromosome 6, and a third copy without it (NOR?). Males only produce haploid NOR+ sperm, while ova are diploid, containing one NOR+ and one NOR? set. Here, we conduct sibship analyses with co-dominant microsatellite markers so as (i) to confirm the purely clonal and maternal transmission of the NOR? set, and (ii) to demonstrate Mendelian segregation and recombination of the NOR+ sets in both sexes. This new reproductive mode in vertebrates (‘pre-equalizing hybrid meiosis’) offers an ideal opportunity to study the evolution of non-recombining genomes. Elucidating the mechanisms that allow simultaneous transmission of two genomes, one of Mendelian, the other of clonal inheritance, might shed light on the general processes that regulate meiosis in vertebrates. PMID:21993502

  8. Linkage disequilibrium and spatial aggregation of genotypes in sexually reproducing populations of Erysiphe necator.

    PubMed

    Brewer, Marin Talbot; Frenkel, Omer; Milgroom, Michael G

    2012-10-01

    Random mating and recombination in heterothallic ascomycetes should result in high genotypic diversity, 1:1 mating-type ratios, and random associations of alleles, or linkage equilibrium, at different loci. To test for random mating in populations of the grape powdery mildew fungus Erysiphe necator, we sampled isolates from vineyards of Vitis vinifera in Burdett, NY (NY09) and Winchester, VA (VA09) at the end of the epidemic in fall 2009. We also sampled isolates from the same Winchester, VA vineyard in spring 2010 at the onset of the next epidemic. Isolates were genotyped for mating type and 11 microsatellite markers. In the spring sample, which originated from ascospore infections, nearly every isolate had a unique genotype. In contrast, fall populations were less diverse. In all, 9 of 45 total genotypes in VA09 were represented by two or more isolates; 3 of 40 total genotypes in NY09 were represented by two or more isolates, with 1 genotype represented by 20 isolates. After clone correction, mating-type ratios in the three populations did not deviate from 1:1. However, even with clone correction, we detected significant linkage disequilibrium (LD) in all populations. Mantel tests detected positive correlations between genetic and physical distances within vineyards. Spatial autocorrelation showed aggregations up to 42 and 3 m in VA09 and NY09, respectively. Spatial autocorrelation most likely results from short dispersal distances. Overall, these results suggest that spatial genetic aggregation and clonal genotypes that arise during the asexual phase of the epidemic contribute to persistent LD even though populations undergo sexual reproduction annually. PMID:22755546

  9. Symmetry Is Related to Sexual Dimorphism in Faces: Data Across Culture and Species

    E-print Network

    Little, Tony

    and sexual dimorphism have been linked to the attractiveness of human face shape. MethodologySymmetry Is Related to Sexual Dimorphism in Faces: Data Across Culture and Species Anthony C both display and assess multiple signals. Two prominently studied traits are symmetry and sexual

  10. SEXUAL SPECIES ARE SEPARATED BY LARGER GENETIC GAPS THAN ASEXUAL SPECIES IN ROTIFERS

    PubMed Central

    Tang, Cuong Q; Obertegger, Ulrike; Fontaneto, Diego; Barraclough, Timothy G

    2014-01-01

    Why organisms diversify into discrete species instead of showing a continuum of genotypic and phenotypic forms is an important yet rarely studied question in speciation biology. Does species discreteness come from adaptation to fill discrete niches or from interspecific gaps generated by reproductive isolation? We investigate the importance of reproductive isolation by comparing genetic discreteness, in terms of intra- and interspecific variation, between facultatively sexual monogonont rotifers and obligately asexual bdelloid rotifers. We calculated the age (phylogenetic distance) and average pairwise genetic distance (raw distance) within and among evolutionarily significant units of diversity in six bdelloid clades and seven monogonont clades sampled for 4211 individuals in total. We find that monogonont species are more discrete than bdelloid species with respect to divergence between species but exhibit similar levels of intraspecific variation (species cohesiveness). This pattern arises because bdelloids have diversified into discrete genetic clusters at a faster net rate than monogononts. Although sampling biases or differences in ecology that are independent of sexuality might also affect these patterns, the results are consistent with the hypothesis that bdelloids diversified at a faster rate into less discrete species because their diversification does not depend on the evolution of reproductive isolation. PMID:24975991

  11. The counterintuitive role of sexual selection in species maintenance and speciation

    PubMed Central

    Servedio, Maria R.; Bürger, Reinhard

    2014-01-01

    The pronounced and elaborate displays that often differ between closely related animal species have led to the common assumption that sexual selection is important in speciation, especially in geographically separated populations. We use population genetic models to examine the ability of Fisherian sexual selection to contribute to lasting species differentiation by isolating its effect after the onset of gene flow between allopatric populations. We show that when sexually selected traits are under ecologically divergent selection, the situation most favorable to speciation, mating preferences tend to introgress faster than trait alleles, causing sexual selection to counter the effects of local adaptation. As a consequence, the net amount of trait divergence often drops with stronger Fisherian sexual selection. Furthermore, alleles for progressively weaker preferences spread in this context until sexual selection is removed. The effects of pure Fisherian sexual selection on species maintenance are thus much more inhibitory than previously assumed. PMID:24821767

  12. Establishment of Genetic Transformation in the Sexually Reproducing Diatoms Pseudo-nitzschia multistriata and Pseudo-nitzschia arenysensis and Inheritance of the Transgene.

    PubMed

    Sabatino, Valeria; Russo, Monia Teresa; Patil, Shrikant; d'Ippolito, Giuliana; Fontana, Angelo; Ferrante, Maria Immacolata

    2015-08-01

    We report the genetic transformation of the planktonic diatoms Pseudo-nitzschia arenysensis and Pseudo-nitzschia multistriata, members of the widely distributed and ecologically important genus Pseudo-nitzschia. P. arenysensis and P. multistriata present the classical size reduction/restitution life cycle and can reproduce sexually. Genetic transformation was achieved with the biolistic method, using the H4 gene promoter from P. multistriata to drive expression of exogenous genes. The transformation was first optimized introducing the Sh ble gene to confer resistance to the antibiotic zeocin. Integration of the transgene was confirmed by PCR and Southern blot analyses. Subsequently, we simultaneously transformed in P. arenysensis two plasmids, one encoding the ?-glucuronidase (GUS) gene together with the plasmid carrying the Sh ble resistance gene, demonstrating the possibility of co-transformation. By transforming a gene encoding a fusion between the histone H4 and the green fluorescent protein (GFP), we demonstrated that fluorescent tagging is possible and that studies for protein localization are feasible. Importantly, we crossed P. arenysensis- and P. multistriata-transformed strains with a wild-type strain of opposite mating type and demonstrated that the transgene can be inherited in the F1 generation. The possibility to transform two diatom species for which genetic crosses are possible opens the way to a number of new approaches, including classical loss of function screens and the possibility to obtain different combinations of double transformants. PMID:25869745

  13. Biological species is the only possible form of existence for higher organisms: the evolutionary meaning of sexual reproduction

    PubMed Central

    2010-01-01

    Consistent holistic view of sexual species as the highest form of biological existence is presented. The Weismann's idea that sex and recombination provide the variation for the natural selection to act upon is dominated in most discussions of the biological meaning of the sexual reproduction. Here, the idea is substantiated that the main advantage of sex is the opposite: the ability to counteract not only extinction but further evolution as well. Living systems live long owing to their ability to reproduce themselves with a high fidelity. Simple organisms (like bacteria) reach the continued existence due to the high fidelity of individual genome replication. In organisms with a large genome and complex development, the achievable fidelity of DNA replication is not enough for the precise reproduction of the genome. Such species must be capable of surviving and must remain unchanged in spite of the continuous changes of their genes. This problem has no solution in the frame of asexual ("homeogenomic") lineages. They would rapidly degrade and become extinct or blurred out in the course of the reckless evolution. The core outcome of the transition to sexual reproduction was the creation of multiorganismic entity - biological species. Individual organisms forfeited their ability to reproduce autonomously. It implies that individual organisms forfeited their ability to substantive evolution. They evolve as a part of the biological species. In case of obligatory sexuality, there is no such a thing as synchronic multi-level selection. Natural selection cannot select anything that is not a unit of reproduction. Hierarchy in biology implies the functional predestination of the parts for the sake of the whole. A crucial feature of the sexual reproduction is the formation of genomes of individual organisms by random picking them over from the continuously shuffled gene pool instead of the direct replication of the ancestor's genome. A clear anti-evolutionary consequence of the sexuality is evident from the fact that the genotypes of the individuals with an enhanced competitiveness are not transmitted to the next generation. Instead, after mating with "ordinary" individuals, these genotypes scatter and rearrange in new gene combinations, thus preventing the winner from exploiting the success. Reviewers This article was reviewed by Pierre Antoine Pontarotti, Michael T. Ghiselin (nominated by Dr. Juergen Brosius) and Emanuel Tannenboum (nominated by Dr. Doron Lancet) PMID:20307287

  14. SEXUALLY DIMORPHIC INFLORESCENCE TRAITS IN A WIND-POLLINATED SPECIES: HERITABILITIES AND GENETIC

    E-print Network

    Campbell, Diane

    SEXUALLY DIMORPHIC INFLORESCENCE TRAITS IN A WIND- POLLINATED SPECIES: HERITABILITIES AND GENETIC and genetic variation were investigated for inflorescence traits in Schiedea adamantis (Caryophyllaceae to wind pollination. For S. adamantis, dimorphism was pronounced for inflorescence condensation and its

  15. Parasite-mediated sexual selection and species divergence in Lake Victoria cichlid fish

    E-print Network

    Parasite-mediated sexual selection and species divergence in Lake Victoria cichlid fish MARTINE E selection in the divergence of two species of Lake Victoria cichlids. Pundamilia pundamilia and Pundamilia underlying the diver- gence of a sibling species pair from Lake Victoria. Pundamilia pundamilia

  16. Sexually selected traits predict patterns of species richness in a diverse clade of suboscine birds.

    PubMed

    Seddon, Nathalie; Merrill, Richard M; Tobias, Joseph A

    2008-05-01

    Whether sexual selection acts as an "engine of speciation" is controversial. Some studies suggest that it promotes the evolution of reproductive isolation, while others find no relationship between sexual selection and species richness. However, the explanatory power of previous models may have been constrained because they employed coarse-scale, between-family comparisons and used mating systems and morphological cues as surrogates for sexual selection. In birds, an obvious missing predictor is song, a sexually selected trait that functions in mate choice and reproductive isolation. We investigated the extent to which plumage dichromatism and song structure predicted species richness in a diverse family of Neotropical suboscine birds, the antbirds (Thamnophilidae). These analyses revealed a positive relationship between the intensity of sexual selection and diversity: genera with higher levels of dichromatism and lower-pitched, more complex songs contained greater numbers of species. This relationship held when controlling for phylogeny and was strengthened by the inclusion of subspecies, suggesting that sexual selection has played a role in the diversification of antbirds. This is the first study to reveal correlations between song structure and species diversity, emphasizing the importance of acoustic signals, and within-family analyses, in comparative studies of sexual selection. PMID:18419570

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

    PubMed

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

    2015-10-01

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

  18. When a clonal genome finds its way back to a sexual species: evidence from ongoing but rare introgression in the hybridogenetic water frog complex.

    PubMed

    Mikulí?ek, P; Kautman, M; Demovi?, B; Janko, K

    2014-03-01

    Besides several exceptions, asexual metazoans are usually viewed as ephemeral sinks for genomes, which become 'frozen' in clonal lineages after their emergence from ancestral sexual species. Here, we investigated whether and at what rate the asexuals are able to introgress their genomes back into the parental sexual population, thus more or less importantly affecting the gene pools of sexual species. We focused on hybridogenetic hybrids of western Palaearctic water frogs (Pelophylax esculentus), which originate through hybridization between P. ridibundus and P. lessonae, but transmit only clonal ridibundus genome into their gametes. Although usually mating with P. lessonae, P. esculentus may upon mating with P. ridibundus or another hybrid produce sexually reproducing P. ridibundus offspring with the introgressed ex-clonal genome. We compared the rate of nuclear amplified fragment length polymorphism (AFLP) and mitochondrial introgression in two types of populations, that is, those where P. ridibundus occurs in isolation and those where it lives with the hybridogens. Although significant differentiation (?pt) between sexual and clonal ridibundus genomes suggested limited gene flow between sexuals and hybridogens, a non-negligible (~5%) proportion of P. ridibundus bore introgressed mtDNA and AFLP markers. Whereas transfer of mtDNA was exclusively unidirectional, introgression of nuclear markers was bidirectional. The proportion of introgressed P. ridibundus was highest in syntopic populations with P. esculentus, proving an ongoing and site-specific interspecific genetic transfer mediated by hybridogenetic hybrids. It turns out that asexual hybrids are not just a sink for genes of sexual species, but may significantly influence the genetic architecture of their sexual counterparts. PMID:26227900

  19. Female social response to male sexual harassment in poeciliid fish: a comparison of six species.

    PubMed

    Dadda, Marco

    2015-01-01

    Sexual harassment is common among poeciliid fish. In some fishes, males show a high frequency of sneak copulation; such sexual activity is costly to the females in terms of foraging efficiency. In mosquitofish (Gambusia holbrooki), when males are present, the distance between females tends to decrease, and this behavior has been interpreted as an adaptive strategy to dilute the costs of male sexual activity. In this study, the tendency to reduce distance in the presence of a male has been investigated in females of six poeciliid species (Girardinus metallicus, Girardinus falcatus, G. holbrooki, Poecilia reticulata, Xiphophorus hellerii, and Xiphophorus mayae) that exhibit different male mating strategies and different levels of sexual activity. Results revealed large interspecific differences in the pattern of female aggregation. Females of species with a high frequency of sneak copulations tended to reduce their social distance in the presence of a male. By contrast, species that rely mainly on courtship showed little or no variation in social distance. The proportion of sneak copulations predicts the degree of variation in female social response, but the amount of total sexual activity does not, suggesting that the change in females' social distance when a male is present may indeed serve to reduce the costs of male sexual harassment. PMID:26483719

  20. Female social response to male sexual harassment in poeciliid fish: a comparison of six species

    PubMed Central

    Dadda, Marco

    2015-01-01

    Sexual harassment is common among poeciliid fish. In some fishes, males show a high frequency of sneak copulation; such sexual activity is costly to the females in terms of foraging efficiency. In mosquitofish (Gambusia holbrooki), when males are present, the distance between females tends to decrease, and this behavior has been interpreted as an adaptive strategy to dilute the costs of male sexual activity. In this study, the tendency to reduce distance in the presence of a male has been investigated in females of six poeciliid species (Girardinus metallicus, Girardinus falcatus, G. holbrooki, Poecilia reticulata, Xiphophorus hellerii, and Xiphophorus mayae) that exhibit different male mating strategies and different levels of sexual activity. Results revealed large interspecific differences in the pattern of female aggregation. Females of species with a high frequency of sneak copulations tended to reduce their social distance in the presence of a male. By contrast, species that rely mainly on courtship showed little or no variation in social distance. The proportion of sneak copulations predicts the degree of variation in female social response, but the amount of total sexual activity does not, suggesting that the change in females' social distance when a male is present may indeed serve to reduce the costs of male sexual harassment. PMID:26483719

  1. In both species oocyte maturation is a contin-uous process that occurs throughout the reproduc-

    E-print Network

    FLATFISHES ON OREGON'S CONTINENTAL SHELF The purpose of this paper is to describe and to compare the food of five flatfish species that actually cooccurred at one specific time and place on the central Oregon (1960), L. bilineata is common on sandy or gravel bottom. The five flatfish spe

  2. Sexual systems in scleractinian corals: an unusual pattern in the reef-building species Diploastrea heliopora

    NASA Astrophysics Data System (ADS)

    Guest, J. R.; Baird, A. H.; Goh, B. P. L.; Chou, L. M.

    2012-09-01

    The sexual system in corals refers to the spatial and temporal pattern of sexual function within an individual coral polyp, colony or population. Although information on sexual systems now exists for over 400 scleractinian species, data are still lacking for some important reef-building taxa. The vast majority of scleractinians are either simultaneous hermaphrodites or gonochoric with other sexual systems rarely occurring. Diploastrea heliopora is one of the most ubiquitous and easily recognised reef-building species in the Indo-West Pacific; however, surprisingly little is known about its reproductive biology. The aim of the present study was to examine the reproductive biology of D. heliopora colonies on chronically impacted, equatorial reefs south of Singapore. Here we show that in Singapore, D. heliopora is a broadcast spawner with predominantly gonochoric polyps. Colonies, however, contained male, female and a low proportion of cosexual polyps during the 14-month sampling period. The most plausible explanation for this is that polyps switch sexes with oogenic and spermatogenic cycles occasionally overlapping. This leads to colony level alternation of sex function within and between breeding seasons. While this sexual system is atypical for scleractinians, it supports molecular evidence that D. heliopora is phylogenetically distinct from species formerly in the family Faviidae.

  3. Species detection and identification in sexual organisms using population genetic theory and DNA sequences.

    PubMed

    Birky, C William

    2013-01-01

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

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

    PubMed Central

    Birky, C. William

    2013-01-01

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

  5. Sexual Dimorphism in the Sceloporus undulatus Species Complex 

    E-print Network

    Dittmer, Drew

    2012-10-19

    The Fence Lizard (Sceloporus undulatus complex) is a wide ranging North American species complex occurring from the eastern seaboard westward through the great plains and central Rocky Mountains and into the American ...

  6. Male secondary sexual structures and the systematics of the Thereus oppia species group (Lepidoptera, Lycaenidae, Eumaeini)

    PubMed Central

    Robbins, Robert K.; Heredia, María Dolores; Busby, Robert C.

    2015-01-01

    Abstract The Thereus oppia species group includes species with and without a scent pad, which is a histologically and morphologically characterized male secondary sexual structure on the dorsal surface of the forewing. To assess the hypothesis that these structures are lost evolutionarily, but not regained (Dollo’s Law), the taxonomy of this species group is revised. Thereus lomalarga sp. n., and Thereus brocki sp. n., are described. Diagnostic traits, especially male secondary structures, within the Thereus oppia species group are illustrated. Distributional and biological information is summarized for each species. Three species have been reared, and the caterpillars eat Loranthaceae. An inferred phylogeny is consistent with the hypothesis that scent pads in the Thereus oppia species group have been lost evolutionarily twice (in allopatry), and not re-gained. PMID:26448715

  7. Gene Expression Differences among Three Neurospora Species Reveal Genes Required for Sexual Reproduction in Neurospora crassa

    PubMed Central

    Lehr, Nina A.; Wang, Zheng; Li, Ning; Hewitt, David A.; López-Giráldez, Francesc; Trail, Frances; Townsend, Jeffrey P.

    2014-01-01

    Many fungi form complex three-dimensional fruiting bodies, within which the meiotic machinery for sexual spore production has been considered to be largely conserved over evolutionary time. Indeed, much of what we know about meiosis in plant and animal taxa has been deeply informed by studies of meiosis in Saccharomyces and Neurospora. Nevertheless, the genetic basis of fruiting body development and its regulation in relation to meiosis in fungi is barely known, even within the best studied multicellular fungal model Neurospora crassa. We characterized morphological development and genome-wide transcriptomics in the closely related species Neurospora crassa, Neurospora tetrasperma, and Neurospora discreta, across eight stages of sexual development. Despite diverse life histories within the genus, all three species produce vase-shaped perithecia. Transcriptome sequencing provided gene expression levels of orthologous genes among all three species. Expression of key meiosis genes and sporulation genes corresponded to known phenotypic and developmental differences among these Neurospora species during sexual development. We assembled a list of genes putatively relevant to the recent evolution of fruiting body development by sorting genes whose relative expression across developmental stages increased more in N. crassa relative to the other species. Then, in N. crassa, we characterized the phenotypes of fruiting bodies arising from crosses of homozygous knockout strains of the top genes. Eight N. crassa genes were found to be critical for the successful formation of perithecia. The absence of these genes in these crosses resulted in either no perithecium formation or in arrested development at an early stage. Our results provide insight into the genetic basis of Neurospora sexual reproduction, which is also of great importance with regard to other multicellular ascomycetes, including perithecium-forming pathogens, such as Claviceps purpurea, Ophiostoma ulmi, and Glomerella graminicola. PMID:25329823

  8. Sex ratio and sexual dimorphism of three lice species with contrasting prevalence parasitizing the house sparrow.

    PubMed

    Pap, Péter László; Adam, Costic?; Vágási, Csongor István; Benk?, Zoltán; Vincze, Orsolya

    2013-02-01

    Female-biased sex ratio is a common phenomenon in parasites; however, the cause and consequence of the skewed sex ratio is less well known. Here, we studied the difference in sex ratio, a possible mechanism responsible for the development of unbalanced proportion of sexes and its consequences on sexual size dimorphism, between 3 louse species parasitizing the house sparrow Passer domesticus. Philopterus fringillae was more prevalent than Sturnidoecus refractariolus and Brueelia cyclothorax. As expected, the most common species, which was probably least affected by isolation and, hence, inbreeding, was characterized by a balanced sex ratio, whereas the 2 other species with low prevalence were significantly more female biased than expected on the basis of the local mate competition hypothesis. Further, in support of this notion, we found that P. fringillae infrapopulation size significantly, and positively, correlated with the sex ratio. Finally, we found significant differences in sexual dimorphism among the 3 louse species and, as expected, the relative size of males was smallest in species with a more female-biased sex ratio. PMID:22924903

  9. Biparentally deserted offspring are viable in a species with intense sexual conflict over care.

    PubMed

    Pogány, Ákos; Kosztolányi, András; Miklósi, Ádám; Komdeur, Jan; Székely, Tamás

    2015-07-01

    Desertion of clutch (or brood) by both parents often leads to breeding failure, since in vast majority of birds care by at least one parent is required for any young to fledge. Recent works in a highly polygamous passerine bird, the Eurasian penduline tit (Remiz pendulinus), suggest that biparental clutch desertion is due to intense sexual conflict over care. However, an alternative yet untested hypothesis for biparental desertion is low offspring viability so that the parents abandon the offspring that have poor prospect for survival. Here we test the latter hypothesis in a common garden experiment by comparing the viability of deserted and cared for eggs. We show that embryonic development does not differ between deserted and cared for eggs. Therefore, sexual conflict over care remains the best supported hypothesis for biparental clutch desertion in penduline tits. Our work points out that conflict over care is a potential - yet rarely considered - cause of biparental nest desertion, and a strong alternative for the traditional explanations of low offspring viability, human disturbance or deteriorating ambient environment. Apart from a handful of species, the intensity of sexual conflict has not been quantified, and we call for further studies to consider sexual conflict as a cause of nest desertion. PMID:25934135

  10. Parental guidance suggested: How parental imprinting evolves through sexual selection as an

    E-print Network

    Todd, Peter M.

    survival. But because reproduction is evolu­ tionarily more important than survival, sexual selection of the bodies in which they are carried (see Dawkins, 1982). Since reproduction in sexually­reproducing speciesParental guidance suggested: How parental imprinting evolves through sexual selection

  11. Parental guidance suggested: How parental imprinting evolves through sexual selection as an

    E-print Network

    Todd, Peter M.

    survival. But because reproduction is evolu- tionarily more important than survival, sexual selection of the bodies in which they are carried (see Dawkins, 1982). Since reproduction in sexually-reproducing speciesParental guidance suggested: How parental imprinting evolves through sexual selection

  12. Application and evaluation of the interlaboratory reproducibility of tRNA intergenic length polymorphism analysis (tDNA-PCR) for identification of Streptococcus species.

    PubMed

    Baele, M; Storms, V; Haesebrouck, F; Devriese, L A; Gillis, M; Verschraegen, G; de Baere, T; Vaneechoutte, M

    2001-04-01

    The discriminatory power, speed, and interlaboratory reproducibility of tRNA intergenic length polymorphism analysis (tDNA-PCR) combined with capillary electrophoresis was evaluated for the identification of streptococci. This method was carried out in three different laboratories under highly standardized conditions for 54 strains belonging to 18 different species. It was concluded that interlaboratory reproducibility of tDNA fingerprints produced by means of capillary electrophoresis was sufficiently high to permit the exchange between different laboratories and the construction of common libraries which can be consulted for comparison with fingerprints obtained independently in separate laboratories. In a second step, 17 other species were included in the study and examined in one of the participating laboratories. All Streptococcus species studied, except S. mitis, S. oralis, S. parasanguinis, S. pneumoniae, S. thermophilus, and S. vestibularis, showed distinguishable tDNA fingerprints. A database of well-characterized strains was constructed to enable computer-aided identification of unknown streptococcal isolates. PMID:11283068

  13. Reproducibility blues.

    PubMed

    Pulverer, Bernd

    2015-11-12

    Research findings advance science only if they are significant, reliable and reproducible. Scientists and journals must publish robust data in a way that renders it optimally reproducible. Reproducibility has to be incentivized and supported by the research infrastructure but without dampening innovation. PMID:26538323

  14. Genetic Structure of Two Protist Species (Myxogastria, Amoebozoa) Suggests Asexual Reproduction in Sexual Amoebae

    PubMed Central

    Fiore-Donno, Anna Maria; Novozhilov, Yuri K.; Meyer, Marianne; Schnittler, Martin

    2011-01-01

    Plasmodial slime molds (Myxogastria or Myxomycetes) are common and widespread unicellular organisms that are commonly assumed to have a sexual life cycle culminating with the formation of often macroscopic fruiting bodies that efficiently disseminate spores. However, laboratory studies based on mating compatibility revealed the coexistence of asexual as well as sexual strains. To test this hypothesis in natural populations, we investigated the genetic variability of two species of the genus Lamproderma. Detailed ecological relevés were carried out in 2007 and 2009 in several deep ravines in the Elbsandsteingebirge (Saxony, south-eastern Germany). Morphological characters of 93 specimens of Lamproderma were recorded and genetic analyses, based on the small subunit ribosomal gene, the internal transcribed spacer 1 and partial elongation factor 1? sequences were carried out for 52 specimens. Genetic analyses showed the existence of two major clades, each composed of several discrete lineages. Most of these lineages were composed of several identical sequences (SSU, ITS 1 and EF-1?) which is explained best by an asexual mode of reproduction. Detrended Correspondence Analysis of morphological characters revealed two morphospecies that corresponded to the two major clades, except for one genotype (Lc6), thus challenging the morphospecies concept. Genetic patterns were not related to the geographical distribution: specimens belonging to the same genotype were found in distinct ravines, suggesting effective long-distance dispersal via spores, except for the Lc6 genotype which was found only in one ravine. Implications for the morphological and biological species concept are discussed. PMID:21829662

  15. Genetic structure of two protist species (Myxogastria, Amoebozoa) suggests asexual reproduction in sexual Amoebae.

    PubMed

    Fiore-Donno, Anna Maria; Novozhilov, Yuri K; Meyer, Marianne; Schnittler, Martin

    2011-01-01

    Plasmodial slime molds (Myxogastria or Myxomycetes) are common and widespread unicellular organisms that are commonly assumed to have a sexual life cycle culminating with the formation of often macroscopic fruiting bodies that efficiently disseminate spores. However, laboratory studies based on mating compatibility revealed the coexistence of asexual as well as sexual strains. To test this hypothesis in natural populations, we investigated the genetic variability of two species of the genus Lamproderma. Detailed ecological relevés were carried out in 2007 and 2009 in several deep ravines in the Elbsandsteingebirge (Saxony, south-eastern Germany). Morphological characters of 93 specimens of Lamproderma were recorded and genetic analyses, based on the small subunit ribosomal gene, the internal transcribed spacer 1 and partial elongation factor 1? sequences were carried out for 52 specimens. Genetic analyses showed the existence of two major clades, each composed of several discrete lineages. Most of these lineages were composed of several identical sequences (SSU, ITS 1 and EF-1?) which is explained best by an asexual mode of reproduction. Detrended Correspondence Analysis of morphological characters revealed two morphospecies that corresponded to the two major clades, except for one genotype (Lc6), thus challenging the morphospecies concept. Genetic patterns were not related to the geographical distribution: specimens belonging to the same genotype were found in distinct ravines, suggesting effective long-distance dispersal via spores, except for the Lc6 genotype which was found only in one ravine. Implications for the morphological and biological species concept are discussed. PMID:21829662

  16. Reliable and reproducible method for rapid identification of Nocardia species by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

    PubMed

    Toyokawa, Masahiro; Kimura, Keigo; Nishi, Isao; Sunada, Atsuko; Ueda, Akiko; Sakata, Tomomi; Asari, Seishi

    2013-01-01

    Recently, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been challenged for the identification of Nocardia species. However, the standard ethanol-formic acid extraction alone is insufficient in allowing the membrane proteins of Nocardia species to be ionized by the matrix. We therefore aimed to establish our new extraction method for the MALDI-TOF MS-based identification of Nocardia species isolates. Our modified extraction procedure is through dissociation in 0.5% Tween-20 followed by bacterial heat-inactivation, mechanical breaking of the cell wall by acid-washed glass beads and protein extraction with formic acid and acetonitrile. As reference methods for species identification, full-length 16S rRNA gene sequencing and some phenotypical tests were used. In a first step, we made our own Nocardia database by analyzing 13 strains (13 different species including N. elegans, N. otitidiscaviarum, N. asiatica, N. abscessus, N. brasiliensis, N. thailandica, N. farcinica, N. nova, N. mikamii, N. cyriacigeorgica, N. asteroids, Nocardiopsis alba, and Micromonospora sp.) and registered to the MALDI BioTyper database. Then we established our database. The analysis of 12 challenge strains using the our database gave a 100% correct identification, including 8 strains identified to the species level and 4 strains to the genus level (N. elegans, N. nova, N. farcinica, Micromonospora sp.) according to the manufacture's log score specifications. In the estimation of reproducibility of our method intended for 4 strains, both within-run and between-run reproducibility were excellent. These data indicates that our method for rapid identification of Nocardia species is with reliability, reproducibility and cost effective. PMID:24800394

  17. Seasonal sexual segregation in two Thalassarche albatross species: competitive exclusion, reproductive role specialization or foraging niche divergence?

    PubMed Central

    Phillips, R. A.; Silk, J. R. D.; Phalan, B.; Catry, P.; Croxall, J. P.

    2004-01-01

    Sexual segregation by micro- or macrohabitat is common in birds, and usually attributed to size-mediated dominance and exclusion of females by larger males, trophic niche divergence or reproductive role specialization. Our study of black-browed albatrosses, Thalassarche melanophrys, and grey-headed albatrosses, T. chrysostoma, revealed an exceptional degree of sexual segregation during incubation, with largely mutually exclusive core foraging ranges for each sex in both species. Spatial segregation was not apparent during brood-guard or post-guard chick rearing, when adults are constrained to feed close to colonies, providing no evidence for dominance-related competitive exclusion at the macrohabitat level. A comprehensive morphometric comparison indicated considerable species and sexual dimorphism in wing area and wing loading that corresponded, both within and between species, to broad-scale habitat preferences relating to wind strength. We suggest that seasonal sexual segregation in these two species is attributable to niche divergence mediated by differences in flight performance. Such sexual segregation may also have implications for conservation in relation to sex-specific overlap with commercial fisheries. PMID:15306353

  18. Effects of the environmental estrogenic contaminants bisphenol A and 17?-ethinyl estradiol on sexual development and adult behaviors in aquatic wildlife species.

    PubMed

    Bhandari, Ramji K; Deem, Sharon L; Holliday, Dawn K; Jandegian, Caitlin M; Kassotis, Christopher D; Nagel, Susan C; Tillitt, Donald E; Vom Saal, Frederick S; Rosenfeld, Cheryl S

    2015-04-01

    Endocrine disrupting chemicals (EDCs), including the mass-produced component of plastics, bisphenol A (BPA) are widely prevalent in aquatic and terrestrial habitats. Many aquatic species, such as fish, amphibians, aquatic reptiles and mammals, are exposed daily to high concentrations of BPA and ethinyl estradiol (EE2), estrogen in birth control pills. In this review, we will predominantly focus on BPA and EE2, well-described estrogenic EDCs. First, the evidence that BPA and EE2 are detectable in almost all bodies of water will be discussed. We will consider how BPA affects sexual and neural development in these species, as these effects have been the best characterized across taxa. For instance, such chemicals have been in many cases reported to cause sex-reversal of males to females. Even if these chemicals do not overtly alter the gonadal sex, there are indications that several EDCs might demasculinize male-specific behaviors that are essential for attracting a mate. In so doing, these chemicals may reduce the likelihood that these males reproduce. If exposed males do reproduce, the concern is that they will then be passing on compromised genetic fitness to their offspring and transmitting potential transgenerational effects through their sperm epigenome. We will thus consider how diverse epigenetic changes might be a unifying mechanism of how BPA and EE2 disrupt several processes across species. Such changes might also serve as universal species diagnostic biomarkers of BPA and other EDCs exposure. Lastly, the evidence that estrogenic EDCs-induced effects in aquatic species might translate to humans will be considered. PMID:25277515

  19. Effects of the environmental estrogenic contaminants bisphenol A and 17?-ethinyl estradiol on sexual development and adult behaviors in aquatic wildlife species

    USGS Publications Warehouse

    Bhandari, Ramji K.; Deem, Sharon L.; Holliday, Dawn K.; Jandegian, Caitlin M.; Kassotis, Christopher D.; Nagel, Susan C.; Tillitt, Donald E.; vom Saal, Frederick S.; Rosenfeld, Cheryl S.

    2015-01-01

    Endocrine disrupting chemicals (EDCs), including the mass-produced component of plastics, bisphenol A (BPA) are widely prevalent in aquatic and terrestrial habitats. Many aquatic species, such as fish, amphibians, aquatic reptiles and mammals, are exposed daily to high concentrations of BPA and ethinyl estradiol (EE2), estrogen in birth control pills. In this review, we will predominantly focus on BPA and EE2, well-described estrogenic EDCs. First, the evidence that BPA and EE2 are detectable in almost all bodies of water will be discussed. We will consider how BPA affects sexual and neural development in these species, as these effects have been the best characterized across taxa. For instance, such chemicals have been in many cases reported to cause sex-reversal of males to females. Even if these chemicals do not overtly alter the gonadal sex, there are indications that several EDCs might demasculinize male-specific behaviors that are essential for attracting a mate. In so doing, these chemicals may reduce the likelihood that these males reproduce. If exposed males do reproduce, the concern is that they will then be passing on compromised genetic fitness to their offspring and transmitting potential transgenerational effects through their sperm epigenome. We will thus consider how diverse epigenetic changes might be a unifying mechanism of how BPA and EE2 disrupt several processes across species. Such changes might also serve as universal species diagnostic biomarkers of BPA and other EDCs exposure. Lastly, the evidence that estrogenic EDCs-induced effects in aquatic species might translate to humans will be considered.

  20. Sexual Dimorphism and Allometric Effects Associated With the Wing Shape of Seven Moth Species of Sphingidae (Lepidoptera: Bombycoidea)

    PubMed Central

    de Camargo, Nícholas Ferreira; Corręa, Danilo do Carmo Vieira; de Camargo, Amabílio J. Aires; Diniz, Ivone Rezende

    2015-01-01

    Sexual dimorphism is a pronounced pattern of intraspecific variation in Lepidoptera. However, moths of the family Sphingidae (Lepidoptera: Bombycoidea) are considered exceptions to this rule. We used geometric morphometric techniques to detect shape and size sexual dimorphism in the fore and hindwings of seven hawkmoth species. The shape variables produced were then subjected to a discriminant analysis. The allometric effects were measured with a simple regression between the canonical variables and the centroid size. We also used the normalized residuals to assess the nonallometric component of shape variation with a t-test. The deformations in wing shape between sexes per species were assessed with a regression between the nonreduced shape variables and the residuals. We found sexual dimorphism in both wings in all analyzed species, and that the allometric effects were responsible for much of the wing shape variation between the sexes. However, when we removed the size effects, we observed shape sexual dimorphism. It is very common for females to be larger than males in Lepidoptera, so it is expected that the shape of structures such as wings suffers deformations in order to preserve their function. However, sources of variation other than allometry could be a reflection of different reproductive flight behavior (long flights in search for sexual mates in males, and flight in search for host plants in females). PMID:26206895

  1. Only Half Right: Species with Female-Biased Sexual Size Dimorphism Consistently Break Rensch's Rule

    PubMed Central

    Webb, Thomas J.; Freckleton, Robert P.

    2007-01-01

    Background Most animal species display Sexual Size Dimorphism (SSD): males and females consistently attain different sizes, most frequently with females being larger than males. However the selective mechanisms driving patterns of SSD remain controversial. ‘Rensch's rule’ proposes a general scaling phenomenon for all taxa, whereby SSD increases with average body size when males are larger than females, and decreases with body size when females are larger than males. Rensch's rule appears to be general in the former case, but there is little evidence for the rule when females are larger then males. Methodology/Principal Findings Using comprehensive data for 1291 species of birds across 30 families, we find strong support for Rensch's rule in families where males are typically larger than females, but no overall support for the rule in families with female-biased SSD. Reviewing previous studies of a broad range of taxa (arthropods, reptiles, fish and birds) showing predominantly female-biased SSD, we conclude that Rensch's conjecture is the exception rather than the rule in such species. Conclusions/Significance The absence of consistent scaling of SSD in taxa with female-biased SSD, the most prevalent direction of dimorphism, calls into question previous general evolutionary explanations for Rensch's rule. We propose that, unlike several other ecological scaling relationships, Rensch's rule does not exist as an independent scaling phenomenon. PMID:17878932

  2. Multigene Assessment of the Species Boundaries and Sexual Status of the Basidiomycetous Yeasts Cryptococcus flavescens and C. terrestris (Tremellales)

    PubMed Central

    Sharma, Lav; Carvalho, Cláudia; Fonseca, Álvaro

    2015-01-01

    Cryptococcus flavescens and C. terrestris are phenotypically indistinguishable sister species that belong to the order Tremellales (Tremellomycetes, Basidiomycota) and which may be mistaken for C. laurentii based on phenotype. Phylogenetic separation between C. flavescens and C. terrestris was based on rDNA sequence analyses, but very little is known on their intraspecific genetic variability or propensity for sexual reproduction. We studied 59 strains from different substrates and geographic locations, and used a multilocus sequencing (MLS) approach complemented with the sequencing of mating type (MAT) genes to assess genetic variation and reexamine the boundaries of the two species, as well as their sexual status. The following five loci were chosen for MLS: the rDNA ITS-LSU region, the rDNA IGS1 spacer, and fragments of the genes encoding the largest subunit of RNA polymerase II (RPB1), the translation elongation factor 1 alpha (TEF1) and the p21-activated protein kinase (STE20). Phylogenetic network analyses confirmed the genetic separation of the two species and revealed two additional cryptic species, for which the names Cryptococcus baii and C. ruineniae are proposed. Further analyses of the data revealed a high degree of genetic heterogeneity within C. flavescens as well as evidence for recombination between lineages detected for this species. Strains of C. terrestris displayed higher levels of similarity in all analysed genes and appear to make up a single recombining group. The two MAT genes (STE3 and SXI1/SXI2) sequenced for C. flavescens strains confirmed the potential for sexual reproduction and suggest the presence of a tetrapolar mating system with a biallelic pheromone/receptor locus and a multiallelic HD locus. In C. terrestris we could only sequence STE3, which revealed a biallelic P/R locus. In spite of the strong evidence for sexual recombination in the two species, attempts at mating compatible strains of both species on culture media were unsuccessful. PMID:25811603

  3. Analysis of conserved microRNAs in floral tissues of sexual and apomictic Boechera species

    PubMed Central

    2011-01-01

    Background Apomixis or asexual seed formation represents a potentially important agronomic trait whose introduction into crop plants could be an effective way to fix and perpetuate a desirable genotype through successive seed generations. However, the gene regulatory pathways underlying apomixis remain unknown. In particular, the potential function of microRNAs, which are known to play crucial roles in many aspects of plant growth and development, remains to be determined with regards to the switch from sexual to apomictic reproduction. Results Using bioinformatics and microarray validation procedures, 51 miRNA families conserved among angiosperms were identified in Boechera. Microarray assay confirmed 15 of the miRNA families that were identified by bioinformatics techniques. 30 cDNA sequences representing 26 miRNAs could fold back into stable pre-miRNAs. 19 of these pre-miRNAs had miRNAs with Boechera-specific nucleotide substitutions (NSs). Analysis of the Gibbs free energy (?G) of these pre-miRNA stem-loops with NSs showed that the Boechera-specific miRNA NSs significantly (p ? 0.05) enhance the stability of stem-loops. Furthermore, six transcription factors, the Squamosa promoter binding protein like SPL6, SPL11 and SPL15, Myb domain protein 120 (MYB120), RELATED TO AP2.7 DNA binding (RAP2.7, TOE1 RAP2.7) and TCP family transcription factor 10 (TCP10) were found to be expressed in sexual or apomictic ovules. However, only SPL11 showed differential expression with significant (p ? 0.05) up-regulation at the megaspore mother cell (MMC) stage of ovule development in apomictic genotypes. Conclusions This study constitutes the first extensive insight into the conservation and expression of microRNAs in Boechera sexual and apomictic species. The miR156/157 target squamosa promoter binding protein-like 11 (SPL11) was found differentially expressed with significant (p ? 0.05) up-regulation at the MMC stage of ovule development in apomictic genotypes. The results also demonstrate that nucleotide changes in mature miRNAs significantly (p ? 0.05) enhance the thermodynamic stability of pre-miRNA stem-loops. PMID:21988906

  4. Production of asexual and sexual offspring in the triploid sexual planarian Dugesia ryukyuensis.

    PubMed

    Kobayashi, Kazuya; Arioka, Sachiko; Hoshi, Motonori; Matsumoto, Midori

    2009-09-01

    Certain freshwater planarians reproduce asexually as well as sexually, and their chromosomal ploidies include polyploidy, aneuploidy and mixoploidy. Previously, we successfully performed an experiment in which a clonal population produced by asexual reproduction of the Dugesia ryukyuensis (OH strain) switched to the sexual mode of reproduction. Worms of this strain are triploid with a pericentric inversion on Chromosome 4. The worms were switched to sexual reproduction after being fed with sexually mature Bdellocephala brunnea, which is a sexually reproducing species. The resulting sexualized OH strain produced cocoons filled with several eggs. Two putative factors, Mendelian factor(s) and chromosomal control(s), have been proposed as determining the reproductive mode. The present study demonstrated that inbreeding of the resultant sexualized worms produced the following four types of offspring through sexual reproduction: diploid asexual worms, triploid asexual worms, diploid sexual worms and triploid sexual worms. The chromosomal mutation on Chromosome 4 was inherited by these offspring independent of their reproductive mode. These results provide two important pieces of information: (i) the putative genetic factor was not necessarily inherited in a Mendelian fashion; and (ii) the reproductive mode is not regulated by chromosomal changes such as polyploidy or chromosomal mutations. This suggests that asexuality in D. ryukyuensis is regulated by an unknown factor(s) other than a Mendelian factor or a chromosomal control. PMID:21392298

  5. Nuptial gifts and sexual behavior in two species of spider (Araneae, Trechaleidae, Paratrechalea)

    NASA Astrophysics Data System (ADS)

    Costa-Schmidt, Luiz Ernesto; Carico, James Edwin; de Araújo, Aldo Mellender

    2008-08-01

    Male delivering of a prey packed in silk as a nuptial gift is rare in spiders and restricted until now to Pisauridae. Here, we describe this behavioral pattern found in two Trechaleidae species, Paratrechalea azul Carico 2005, and Paratrechalea ornata (Mello-Leităo 1943), mainly based on field observations. We observed the following steps of sexual behavior: sperm induction, nuptial gift construction, mate searching, pre-copulatory courtship, copulation, and copulatory ending. In this group, a nuptial gift consists of a prey wrapped in silk, which appears as a white rounded shape. The male carries his nuptial gift in his chelicerae while searching for a female. When he finds a female, he shows a stereotyped courting behavior consisting of a hyperflexed posture that is also assumed by the receptive female while they face each other. The copulatory position and pattern is similar to that found in other Lycosoidea: the male mounts the female and makes a total of four palpal insertions while alternating sides. However, after each palpal insertion the male dismounts and returns to a frontal position while biting the gift. Copulatory courtship is evidenced by palpal and leg movements. The copulation ends by female initiative and she almost always retains the nuptial gift. No case of pre-copulatory or post-copulatory cannibalism has been recorded. Descriptions of nuptial gift construction by males and copulation in these species, as well as hypotheses about the origin of nuptial gift construction among spiders, are presented. These descriptions are the first records of such nuptial gift offering for Neotropical spiders and for non-Pisauridae species as well.

  6. An in vitro biofilm model system maintaining a highly reproducible species and metabolic diversity approaching that of the human oral microbiome

    PubMed Central

    2013-01-01

    Background Our knowledge of microbial diversity in the human oral cavity has vastly expanded during the last two decades of research. However, much of what is known about the behavior of oral species to date derives from pure culture approaches and the studies combining several cultivated species, which likely does not fully reflect their function in complex microbial communities. It has been shown in studies with a limited number of cultivated species that early oral biofilm development occurs in a successional manner and that continuous low pH can lead to an enrichment of aciduric species. Observations that in vitro grown plaque biofilm microcosms can maintain similar pH profiles in response to carbohydrate addition as plaque in vivo suggests a complex microbial community can be established in the laboratory. In light of this, our primary goal was to develop a robust in vitro biofilm-model system from a pooled saliva inoculum in order to study the stability, reproducibility, and development of the oral microbiome, and its dynamic response to environmental changes from the community to the molecular level. Results Comparative metagenomic analyses confirmed a high similarity of metabolic potential in biofilms to recently available oral metagenomes from healthy subjects as part of the Human Microbiome Project. A time-series metagenomic analysis of the taxonomic community composition in biofilms revealed that the proportions of major species at 3 hours of growth are maintained during 48 hours of biofilm development. By employing deep pyrosequencing of the 16S rRNA gene to investigate this biofilm model with regards to bacterial taxonomic diversity, we show a high reproducibility of the taxonomic carriage and proportions between: 1) individual biofilm samples; 2) biofilm batches grown at different dates; 3) DNA extraction techniques and 4) research laboratories. Conclusions Our study demonstrates that we now have the capability to grow stable oral microbial in vitro biofilms containing more than one hundred operational taxonomic units (OTU) which represent 60-80% of the original inoculum OTU richness. Previously uncultivated Human Oral Taxa (HOT) were identified in the biofilms and contributed to approximately one-third of the totally captured 16S rRNA gene diversity. To our knowledge, this represents the highest oral bacterial diversity reported for an in vitro model system so far. This robust model will help investigate currently uncultivated species and the known virulence properties for many oral pathogens not solely restricted to pure culture systems, but within multi-species biofilms. PMID:24451062

  7. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. DNA sequence data and morphology define Cryphonectria species in Europe, Chin...

    E-print Network

    Reproduced with permission of the copyright owner. Further reproduction prohibited without reproduction prohibited without permission. #12;Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. #12;Reproduced with permission of the copyright owner. Further

  8. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The species of Chondrophycus and Laurencia (Rhodomelaceae, Ceramiales) occurr...

    E-print Network

    Wynne, Michael J.

    Reproduced with permission of the copyright owner. Further reproduction prohibited without;Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. #12;Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. #12

  9. Molecular and Morphological Data Support the Existence of a Sexual Cycle in Species of the Genus Paracoccidioides

    PubMed Central

    Teixeira, Marcus de Melo; Theodoro, Raquel Cordeiro; Derengowski, Lorena da Silveira; Nicola, André Moraes; Bagagli, Eduardo

    2013-01-01

    The genus Paracoccidioides includes the thermodimorphic species Paracoccidioides brasiliensis and P. lutzii, both of which are etiologic agents of paracoccidioidomycosis, a systemic mycosis that affects humans in Latin America. Despite the common occurrence of a sexual stage among closely related fungi, this has not been observed with Paracoccidioides species, which have thus been considered asexual. Molecular evolutionary studies revealed recombination events within isolated populations of the genus Paracoccidioides, suggesting the possible existence of a sexual cycle. Comparative genomic analysis of all dimorphic fungi and Saccharomyces cerevisiae demonstrated the presence of conserved genes involved in sexual reproduction, including those encoding mating regulators such as MAT, pheromone receptors, pheromone-processing enzymes, and mating signaling regulators. The expression of sex-related genes in the yeast and mycelial phases of both Paracoccidioides species was also detected by real-time PCR, with nearly all of these genes being expressed preferentially in the filamentous form of the pathogens. In addition, the expression of sex-related genes was responsive to the putative presence of pheromone in the supernatants obtained from previous cocultures of strains of two different mating types. In vitro crossing of isolates of different mating types, discriminated by phylogenetic analysis of the ?-box (MAT1-1) and the high-mobility-group (HMG) domain (MAT1-2), led to the identification of the formation of young ascocarps with constricted coiled hyphae related to the initial stage of mating. These genomic and morphological analyses strongly support the existence of a sexual cycle in species of the genus Paracoccidioides. PMID:23125354

  10. KIND Reproducibles.

    ERIC Educational Resources Information Center

    KIND Teacher, 1990

    1990-01-01

    Presented are 14 student worksheets for use in teaching about environmental conservation. Topics of these games, puzzles include pollution, rainforests, endangered species, habitat destruction, and solid waste. An answer sheet for teachers is included. (CW)

  11. Elusive reproducibility.

    PubMed

    Gori, Gio Batta

    2014-08-01

    Reproducibility remains a mirage for many biomedical studies because inherent experimental uncertainties generate idiosyncratic outcomes. The authentication and error rates of primary empirical data are often elusive, while multifactorial confounders beset experimental setups. Substantive methodological remedies are difficult to conceive, signifying that many biomedical studies yield more or less plausible results, depending on the attending uncertainties. Real life applications of those results remain problematic, with important exceptions for counterfactual field validations of strong experimental signals, notably for some vaccines and drugs, and for certain safety and occupational measures. It is argued that industrial, commercial and public policies and regulations could not ethically rely on unreliable biomedical results; rather, they should be rationally grounded on transparent cost-benefit tradeoffs. PMID:24882687

  12. Quantitative genetics of sexual display, ejaculate quality and size in a lekking species.

    PubMed

    Chargé, Rémi; Teplitsky, Céline; Hingrat, Yves; Saint Jalme, Michel; Lacroix, Frédéric; Sorci, Gabriele

    2013-03-01

    The investment into extravagant sexual display and competitive sperm are two essential components of pre- and post-copulatory sexual selection. Even though the selective forces acting on sexual display and sperm characteristics have been extensively studied in recent years, the genetic architecture underlying the expression of these traits has been rarely explored. Here, we estimated the genetic variances and covariances of traits linked with ejaculate size and quality, and sexual display in the houbara bustard (Chlamydotis undulata undulata, Jacquin 1784). Using a very large pedigree-based data set, we show that sexual signalling and ejaculate size (but not ejaculate quality) are heritable and genetically positively correlated. The matrix of genetic covariances also provided support for some across-sex correlations: male and female gamete numbers are positively correlated, and more surprisingly, male display and female gamete numbers are also positively correlated. These results can have important implications for the understanding of the evolution of sperm traits and sexual display in animals. PMID:23228188

  13. Discovery of a Modified Tetrapolar Sexual Cycle in Cryptococcus amylolentus and the Evolution of MAT in the Cryptococcus Species Complex

    PubMed Central

    Fraser, James A.; Hsueh, Yen-Ping; Averette, Anna Floyd; Li, Wenjun; Dietrich, Fred S.; Heitman, Joseph

    2012-01-01

    Sexual reproduction in fungi is governed by a specialized genomic region called the mating-type locus (MAT). The human fungal pathogenic and basidiomycetous yeast Cryptococcus neoformans has evolved a bipolar mating system (a, ?) in which the MAT locus is unusually large (>100 kb) and encodes >20 genes including homeodomain (HD) and pheromone/receptor (P/R) genes. To understand how this unique bipolar mating system evolved, we investigated MAT in the closely related species Tsuchiyaea wingfieldii and Cryptococcus amylolentus and discovered two physically unlinked loci encoding the HD and P/R genes. Interestingly, the HD (B) locus sex-specific region is restricted (?2 kb) and encodes two linked and divergently oriented homeodomain genes in contrast to the solo HD genes (SXI1?, SXI2a) of C. neoformans and Cryptococcus gattii. The P/R (A) locus contains the pheromone and pheromone receptor genes but has expanded considerably compared to other outgroup species (Cryptococcus heveanensis) and is linked to many of the genes also found in the MAT locus of the pathogenic Cryptococcus species. Our discovery of a heterothallic sexual cycle for C. amylolentus allowed us to establish the biological roles of the sex-determining regions. Matings between two strains of opposite mating-types (A1B1×A2B2) produced dikaryotic hyphae with fused clamp connections, basidia, and basidiospores. Genotyping progeny using markers linked and unlinked to MAT revealed that meiosis and uniparental mitochondrial inheritance occur during the sexual cycle of C. amylolentus. The sexual cycle is tetrapolar and produces fertile progeny of four mating-types (A1B1, A1B2, A2B1, and A2B2), but a high proportion of progeny are infertile, and fertility is biased towards one parental mating-type (A1B1). Our studies reveal insights into the plasticity and transitions in both mechanisms of sex determination (bipolar versus tetrapolar) and sexual reproduction (outcrossing versus inbreeding) with implications for similar evolutionary transitions and processes in fungi, plants, and animals. PMID:22359516

  14. Anthropogenic ecosystem fragmentation drives shared and unique patterns of sexual signal divergence among three species of Bahamian mosquitofish.

    PubMed

    Giery, Sean T; Layman, Craig A; Langerhans, R Brian

    2015-08-01

    When confronted with similar environmental challenges, different organisms can exhibit dissimilar phenotypic responses. Therefore, understanding patterns of phenotypic divergence for closely related species requires considering distinct evolutionary histories. Here, we investigated how a common form of human-induced environmental alteration, habitat fragmentation, may drive phenotypic divergence among three closely related species of Bahamian mosquitofish (Gambusia spp.). Focusing on one phenotypic trait (male coloration), having a priori predictions of divergence, we tested whether populations persisting in fragmented habitats differed from those inhabiting unfragmented habitats and examined the consistency of the pattern across species. Species exhibited both shared and unique patterns of phenotypic divergence between the two types of habitats, with shared patterns representing the stronger effect. For all species, populations in fragmented habitats had fewer dorsal-fin spots. In contrast, the magnitude and trajectory of divergence in dorsal-fin color, a sexually selected trait, differed among species. We identified fragmentation-mediated increased turbidity as a possible driver of these trait shifts. These results suggest that even closely related species can exhibit diverse phenotypic responses when encountering similar human-mediated selection regimes. This element of unpredictability complicates forecasting the phenotypic responses of wild organisms faced with anthropogenic change - an important component of biological conservation and ecosystem management. PMID:26240605

  15. Anthropogenic ecosystem fragmentation drives shared and unique patterns of sexual signal divergence among three species of Bahamian mosquitofish

    PubMed Central

    Giery, Sean T; Layman, Craig A; Langerhans, R Brian

    2015-01-01

    When confronted with similar environmental challenges, different organisms can exhibit dissimilar phenotypic responses. Therefore, understanding patterns of phenotypic divergence for closely related species requires considering distinct evolutionary histories. Here, we investigated how a common form of human-induced environmental alteration, habitat fragmentation, may drive phenotypic divergence among three closely related species of Bahamian mosquitofish (Gambusia spp.). Focusing on one phenotypic trait (male coloration), having a priori predictions of divergence, we tested whether populations persisting in fragmented habitats differed from those inhabiting unfragmented habitats and examined the consistency of the pattern across species. Species exhibited both shared and unique patterns of phenotypic divergence between the two types of habitats, with shared patterns representing the stronger effect. For all species, populations in fragmented habitats had fewer dorsal-fin spots. In contrast, the magnitude and trajectory of divergence in dorsal-fin color, a sexually selected trait, differed among species. We identified fragmentation-mediated increased turbidity as a possible driver of these trait shifts. These results suggest that even closely related species can exhibit diverse phenotypic responses when encountering similar human-mediated selection regimes. This element of unpredictability complicates forecasting the phenotypic responses of wild organisms faced with anthropogenic change – an important component of biological conservation and ecosystem management. PMID:26240605

  16. Species-specific loss of sexual dimorphism in vocal effectors accompanies vocal simplification in African clawed frogs (Xenopus).

    PubMed

    Leininger, Elizabeth C; Kitayama, Ken; Kelley, Darcy B

    2015-03-01

    Phylogenetic studies can reveal patterns of evolutionary change, including the gain or loss of elaborate courtship traits in males. Male African clawed frogs generally produce complex and rapid courtship vocalizations, whereas female calls are simple and slow. In a few species, however, male vocalizations are also simple and slow, suggesting loss of male-typical traits. Here, we explore features of the male vocal organ that could contribute to loss in two species with simple, slow male calls. In Xenopus boumbaensis, laryngeal morphology is more robust in males than in females. Larynges are larger, have a more complex cartilaginous morphology and contain more muscle fibers. Laryngeal muscle fibers are exclusively fast-twitch in males but are both fast- and slow-twitch in females. The laryngeal electromyogram, a measure of neuromuscular synaptic strength, shows greater potentiation in males than in females. Male-specific physiological features are shared with X. laevis, as well as with a species of the sister clade, Silurana tropicalis, and thus are likely ancestral. In X. borealis, certain aspects of laryngeal morphology and physiology are sexually monomorphic rather than dimorphic. In both sexes, laryngeal muscle fibers are of mixed-twitch type, which limits the production of muscle contractions at rapid intervals. Muscle activity potentiation and discrete tension transients resemble female rather than male X. boumbaensis. The de-masculinization of these laryngeal features suggests an alteration in sensitivity to the gonadal hormones that are known to control the sexual differentiation of the larynx in other Xenopus and Silurana species. PMID:25788725

  17. Does selection on floral odor promote differentiation among populations and species of the sexually deceptive orchid genus Ophrys?

    PubMed

    Mant, Jim; Peakall, Rod; Schiestl, Florian P

    2005-07-01

    Sexually deceptive orchids from the genus Ophrys attract their pollinators primarily through the chemical mimicry of female hymenopteran sex pheromones, thereby deceiving males into attempted matings with the orchid labellum. Floral odor traits are crucial for the reproductive success of these pollinator-limited orchids, as well as for maintaining reproductive isolation through the attraction of specific pollinators. We tested for the signature of pollinator-mediated selection on floral odor by comparing intra and interspecific differentiation in odor compounds with that found at microsatellite markers among natural populations. Three regions from southern Italy were sampled. We found strong floral odor differentiation among allopatric populations within species, among allopatric species and among sympatric species. Population differences in odor were also reflected in significant variation in the attractivity of floral extracts to the pollinator, Colletes cunicularius. Odor compounds that are electrophysiologically active in C. cunicularius males, especially alkenes, were more strongly differentiated among conspecific populations than nonactive compounds in the floral odor. In marked contrast to these odor patterns, there was limited population or species level differentiation in microsatellites (FST range 0.005 to 0.127, mean FST 0.075). We propose that the strong odor differentiation and lack of genetic differentiation among sympatric taxa indicates selection imposed by the distinct odor preferences of different pollinating species. Within species, low FST values are suggestive of large effective population sizes and indicate that divergent selection rather than genetic drift accounts for the strong population differentiation in odor. The higher differentiation in active versus non-active odor compounds suggests that divergent selection among orchid populations may be driven by local pollinator preferences for those particular compounds critical for pollinator attraction. PMID:16153031

  18. A new species of Hydropisphaera, H. bambusicola, is the sexual state of Gliomastix fusigera

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new species of Hydropisphaera, H. bambusicola sp. nov., is described and illustrated based on a collection from Bambusa vulgaris in Martinique. The asexual state was obtained in culture and identified as Gliomastix fusigera. Gliomastix fusigera is an anamorph species that occurs on members of the ...

  19. Alteration of sexual reproduction and genetic diversity in the kelp species Laminaria digitata at the southern limit of its range.

    PubMed

    Oppliger, Luz Valeria; von Dassow, Peter; Bouchemousse, Sarah; Robuchon, Marine; Valero, Myriam; Correa, Juan A; Mauger, Stéphane; Destombe, Christophe

    2014-01-01

    Adaptation to marginal habitats at species range-limits has often been associated with parthenogenetic reproduction in terrestrial animals and plants. Laboratory observations have shown that brown algae exhibit a high propensity for parthenogenesis by various mechanisms. The kelp Laminaria digitata is an important component of the ecosystem in Northern European rocky intertidal habitats. We studied four L. digitata populations for the effects of marginality on genetic diversity and sexual reproduction. Two populations were marginal: One (Locquirec, in Northern Brittany) was well within the geographic range, but was genetically isolated from other populations by large stretches of sandy beaches. Another population was at the range limits of the species (Quiberon, in Southern Brittany) and was exposed to much higher seasonal temperature changes. Microsatellite analyses confirmed that these populations showed decreased genetic and allelic diversity, consistent with marginality and genetic isolation. Sporophytes from both marginal populations showed greatly diminished spore-production compared to central populations, but only the southern-limit population (Quiberon) showed a high propensity for producing unreduced (2N) spores. Unreduced 2N spores formed phenotypically normal gametophytes with nuclear area consistent with ?2N DNA contents, and microsatellite studies suggested these were produced at least in part by automixis. However, despite this being the dominant path of spore production in Quiberon sporophyte individuals, the genetic evidence indicated the population was maintained mostly by sexual reproduction. Thus, although spore production and development showed the expected tendency of geographical parthenogenesis in marginal populations, this appeared to be a consequence of maladaptation, rather than an adaptation to, life in a marginal habitat. PMID:25019953

  20. Alteration of Sexual Reproduction and Genetic Diversity in the Kelp Species Laminaria digitata at the Southern Limit of Its Range

    PubMed Central

    Oppliger, Luz Valeria; von Dassow, Peter; Bouchemousse, Sarah; Robuchon, Marine; Valero, Myriam; Correa, Juan A.; Mauger, Stéphane; Destombe, Christophe

    2014-01-01

    Adaptation to marginal habitats at species range-limits has often been associated with parthenogenetic reproduction in terrestrial animals and plants. Laboratory observations have shown that brown algae exhibit a high propensity for parthenogenesis by various mechanisms. The kelp Laminaria digitata is an important component of the ecosystem in Northern European rocky intertidal habitats. We studied four L. digitata populations for the effects of marginality on genetic diversity and sexual reproduction. Two populations were marginal: One (Locquirec, in Northern Brittany) was well within the geographic range, but was genetically isolated from other populations by large stretches of sandy beaches. Another population was at the range limits of the species (Quiberon, in Southern Brittany) and was exposed to much higher seasonal temperature changes. Microsatellite analyses confirmed that these populations showed decreased genetic and allelic diversity, consistent with marginality and genetic isolation. Sporophytes from both marginal populations showed greatly diminished spore-production compared to central populations, but only the southern-limit population (Quiberon) showed a high propensity for producing unreduced (2N) spores. Unreduced 2N spores formed phenotypically normal gametophytes with nuclear area consistent with ?2N DNA contents, and microsatellite studies suggested these were produced at least in part by automixis. However, despite this being the dominant path of spore production in Quiberon sporophyte individuals, the genetic evidence indicated the population was maintained mostly by sexual reproduction. Thus, although spore production and development showed the expected tendency of geographical parthenogenesis in marginal populations, this appeared to be a consequence of maladaptation, rather than an adaptation to, life in a marginal habitat. PMID:25019953

  1. Novel microRNAs and microsatellite-like small RNAs in sexual and apomictic Boechera species.

    PubMed

    Amiteye, Samuel; Corral, Jose M; Vogel, Heiko; Kuhlmann, Markus; Mette, Michael F; Sharbel, Timothy F

    2013-01-01

    Apomixis refers to plant asexual reproduction through seeds that give rise to progeny which are genotypically identical to the maternal parent. It has evolved from many different sexual taxa although the underlying genetic factors remain unknown. Previous analyses of the over-representation of transcription factors, in a comparison of microdissected ovules from apomictic and sexual Boechera, showed that many transcription factor mRNAs possessed microRNA (miRNAs) binding sites, thus pointing to miRNAs as potentially important factors that may be involved in the regulatory switch from sexual to apomictic reproduction. A microarray-based approach was used to identify (1) 673 microsatellitelike small RNAs (misRNAs) containing predominantly 2-7 repeats of (GAA)n/(CUU)n, (GCA)n/(CGU)n, (GGA)n/(CCU)n, (GGU)n/(CCA)n and (UGA)n/(ACU)n, and (2) 166 more typical non-repeat small RNAs. In total, 87 small RNAs were found to be located in cDNAs that could fold into stem-loop structures and thus represent miRNA molecules. In addition, 109 Boechera small RNAs including both misRNAs and non-repeat small RNAs, showed significant homology to 407 Arabidopsis thaliana small RNAs including the A. thaliana pollen-specific ath-miR5021. This indicates that only a fraction of the identified small RNAs are unique to Boechera. Ten small RNAs were validated using a Northern blot assay on flower and leaf tissues, eight of which showed flower-specific expression with varying abundance. The potential binding sites of many of the misRNAs and non-repeat small RNAs occur predominantly in exonic regions. This feature coupled with their flower-specific pattern of expression is suggestive of their probable role in post-transcriptional gene regulation. We propose that quantitative variation for misRNA target binding (and hence post-transcriptional gene regulation) could arise via microsatellite length polymorphisms occurring either in misRNA precursors or in their gene targets. PMID:25070713

  2. Sexual differences in the brain catecholamine content in four species of tropical bats.

    PubMed

    Ortega-Corona, B G; Garrido-Rodríguez, D; García-Bulnes, G; Esparza-Avalos, N; Morales-Rosas, J

    1992-04-01

    The catecholamines dopamine, norepinephrine and epinephrine were studied in the brains of male and female tropical bats of four species, with different feeding habits (insectivorous, frugivorous, omnivorous and pollen eater). They were trapped in a refuge at 18 degrees 24'24''N, 99 degrees 02'08''W with a mean annual temperature of 25.8 degrees C, in a tropical deciduous forest. The three catecholamines occur in both sexes of all four species, in levels which are statistically different among species as well as between sexes. Dopamine and norepinephrine levels were higher in males than females, but the opposite occurs with epinephrine. These findings suggest that changes in catecholamine levels are intimately involved in the reproductive pattern of the species studied. PMID:1297171

  3. The evolutionary dynamics of major regulators for sexual development among Hymenoptera species

    PubMed Central

    Biewer, Matthias; Schlesinger, Francisca; Hasselmann, Martin

    2015-01-01

    All hymenopteran species, such as bees, wasps and ants, are characterized by the common principle of haplodiploid sex determination in which haploid males arise from unfertilized eggs and females from fertilized eggs. The underlying molecular mechanism has been studied in detail in the western honey bee Apis mellifera, in which the gene complementary sex determiner (csd) acts as primary signal of the sex determining pathway, initiating female development by csd-heterozygotes. Csd arose from gene duplication of the feminizer (fem) gene, a transformer (tra) ortholog, and mediates in conjunction with transformer2 (tra2) sex-specific splicing of fem. Comparative molecular analyses identified fem/tra and its downstream target doublesex (dsx) as conserved unit within the sex determining pathway of holometabolous insects. In this study, we aim to examine evolutionary differences among these key regulators. Our main hypothesis is that sex determining key regulators in Hymenoptera species show signs of coevolution within single phylogenetic lineages. We take advantage of several newly sequenced genomes of bee species to test this hypothesis using bioinformatic approaches. We found evidences that duplications of fem are restricted to certain bee lineages and notable amino acid differences of tra2 between Apis and non-Apis species propose structural changes in Tra2 protein affecting co-regulatory function on target genes. These findings may help to gain deeper insights into the ancestral mode of hymenopteran sex determination and support the common view of the remarkable evolutionary flexibility in this regulatory pathway. PMID:25914717

  4. The evolutionary dynamics of major regulators for sexual development among Hymenoptera species.

    PubMed

    Biewer, Matthias; Schlesinger, Francisca; Hasselmann, Martin

    2015-01-01

    All hymenopteran species, such as bees, wasps and ants, are characterized by the common principle of haplodiploid sex determination in which haploid males arise from unfertilized eggs and females from fertilized eggs. The underlying molecular mechanism has been studied in detail in the western honey bee Apis mellifera, in which the gene complementary sex determiner (csd) acts as primary signal of the sex determining pathway, initiating female development by csd-heterozygotes. Csd arose from gene duplication of the feminizer (fem) gene, a transformer (tra) ortholog, and mediates in conjunction with transformer2 (tra2) sex-specific splicing of fem. Comparative molecular analyses identified fem/tra and its downstream target doublesex (dsx) as conserved unit within the sex determining pathway of holometabolous insects. In this study, we aim to examine evolutionary differences among these key regulators. Our main hypothesis is that sex determining key regulators in Hymenoptera species show signs of coevolution within single phylogenetic lineages. We take advantage of several newly sequenced genomes of bee species to test this hypothesis using bioinformatic approaches. We found evidences that duplications of fem are restricted to certain bee lineages and notable amino acid differences of tra2 between Apis and non-Apis species propose structural changes in Tra2 protein affecting co-regulatory function on target genes. These findings may help to gain deeper insights into the ancestral mode of hymenopteran sex determination and support the common view of the remarkable evolutionary flexibility in this regulatory pathway. PMID:25914717

  5. Sexual Violence: Sexual assault

    E-print Network

    Li, X. Rong

    Medical Options · Medical Care/Treatment & Evidence Collection · Student Health Services Reporting SexualSexual Violence: Sexual assault Sexual harassment Stalking Intimate partner abuse/domestic violence Resources FOR VICTIMS OF SEXUAL ASSAULT INFORMATION TO ASSIST MEMBERS OF THE UNIVERSITY OF NEW ORLEANS

  6. Sexual Harassment and Sexual Bulllying

    MedlinePLUS

    ... Snacking Losing Weight Safely Sexual Harassment and Sexual Bullying KidsHealth > Teens > Sexual Health > For Guys > Sexual Harassment ... being sexually harassed or bullied. What Are Sexual Bullying and Harassment? Just like other kinds of bullying, ...

  7. Non-developing ascospores in apothecia of asexually reproducing lichen-forming fungi.

    PubMed

    Molina, M Carmen; Divakar, Pradeep K; Zhang, Ning; González, Natalia; Struwe, Lena

    2013-09-01

    The presence of apothecia in mixed species (vegetatively reproducing lichens, occasionally producing ascomata) has been interpreted as a mechanism to increase genetic variability in mostly clonal populations. However, spore viability from these apothecia has not been studied. We asked whether ascospores of the mixed species Physconia grisea are viable and thereby contribute to increasing the genetic diversity within populations of this species. An ontogenetic study of spores in cultures of P. grisea and a related sexual species (P. distorta), showed that although mature apothecia from both species produced and discharged meiospores capable of germination, spores from P. grisea were only rarely (0.43%) able to continue development whereas those from P. distorta germinated and developed successfully. The strongly reduced viability of P. grisea spores suggested that they do not have a strong reproductive function, at least in the two local populations analyzed. Additionally, we show that the segregation of Physconia grisea ssp. lilacina does not have molecular support. PMID:24568030

  8. 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 ...

  9. Migration and the Origin of Species Claus Rueffler

    E-print Network

    Rueffler, Claus

    to the biological relevant effect of migration in sexually reproducing plant and animal populations. Although stillMigration and the Origin of Species Claus Rueffler Mathematics and BioSciences Group Department. Messer, R. Schroeder and R. Wodak, eds. Migrations: Interdisciplinary Perspectives (2012), pp. 327

  10. Variation in social and sexual behaviour in four species of aposematic seed bugs (Hemiptera: Lygaeidae): the role of toxic and non-toxic food.

    PubMed

    Burdfield-Steel, Emily R; Dougherty, Liam R; Smith, Lynsey A; Collins, Laura A; Shuker, David M

    2013-10-01

    Understanding variation in social behaviour both within and among species continues to be a challenge. Evolutionary or ecological theory typically predicts the optimal behaviour for an animal under a given set of circumstances, yet the real world presents much greater variation in behaviour than predicted. This variation is apparent in many social and sexual interactions, including mate choice, and has led to a renewed focus on individual variation in behaviour. Here we explore within and among species variation in social behaviour in four species of aposematic seed bug (Lygaeidae: Hemiptera). These species are Müllerian mimics, with characteristic warning colouration advertising their chemical toxicity. We examine the role of diet in generating variation in two key behaviours: social aggregation of nymphs and mate choice. We test how behaviour varies with exposure to either milkweed (a source of defensive compounds) or sunflower (that provides no defence). We show that although the four species vary in their food preferences, and diet influences their life-history (as highlighted by body size), social aggregation and mate choice is relatively unaffected by diet. We discuss our findings in terms of the evolution of aposematism, the importance of automimicry, and the role of diet in generating behavioural variation. PMID:23796773

  11. New species of Ophiostomatales from Scolytinae and Platypodinae beetles in the Cape Floristic Region, including the discovery of the sexual state of Raffaelea.

    PubMed

    Musvuugwa, Tendai; de Beer, Z Wilhelm; Duong, Tuan A; Dreyer, Léanne L; Oberlander, Kenneth C; Roets, Francois

    2015-10-01

    Olea capensis and Rapanea melanophloeos are important canopy trees in South African Afromontane forests. Dying or recently dead individuals of these trees are often infested by Scolytinae and Platypodinae (Curculionidae) beetles. Fungi were isolated from the surfaces of beetles emerging from wood samples and their galleries. Based on micro-morphological and phylogenetic analyses, four fungal species in the Ophiostomatales were isolated. These were Sporothrix pallida and three taxa here newly described as Sporothrix aemulophila sp. nov., Raffaelea vaginata sp. nov. and Raffaelea rapaneae sp. nov. This study represents the first collection of S. pallida, a species known from many environmental samples from across the world, from Scolytinae beetles. S. aemulophila sp. nov. is an associate of the ambrosia beetle Xyleborinus aemulus. R. rapaneae sp. nov. and R. vaginata sp. nov. were associated with a Lanurgus sp. and Platypodinae beetle, respectively, and represent the first Raffaelea spp. reported from the Cape Floristic Region. Of significance is that R. vaginata produced a sexual state analogous with those of Ophiostoma seticolle and O. deltoideosporum that also grouped in our analyses in Raffaelea s. str., to date considered an asexual genus. The morphology of the ossiform ascospores and anamorphs of the three species corresponded and the generic circumscription of Raffaelea is thus emended to accommodate sexual states. The two known species are provided with new combinations, namely Raffaelea seticollis (R.W. Davidson) Z.W. de Beer and T.A. Duong comb. nov. and Raffaelea deltoideospora (Olchow. and J. Reid) Z.W. de Beer and T.A. Duong comb. nov. PMID:26275876

  12. Innate sexuality determines the mechanisms of telomere maintenance.

    PubMed

    Tasaka, Kenta; Yokoyama, Naoki; Nodono, Hanae; Hoshi, Motonori; Matsumoto, Midori

    2013-01-01

    Recently, telomere length has been shown to be differentially regulated in asexually and sexually reproducing planarians. In addition, it was found that asexual worms maintain telomere length somatically during reproduction by fission or when regeneration is induced by amputation, whereas sexual worms only achieve telomere elongation through sexual reproduction. We have established an experimental bioassay system to induce switching from asexual to sexual reproduction in planarians, that is, sexualization. In this study, the relationship between the reproductive mode and telomere maintenance was investigated using innate asexually reproducing worms, innate sexually reproducing worms, and experimentally sexualized worms. Here, we show that innate asexual planarians maintain telomere length during cell division and that innate sexual planarians exhibit telomere shortening. However, experimental sexualized worms maintain telomere length during cell division. These results indicate that innate sexuality is linked to the mechanism of telomere maintenance. PMID:23319366

  13. Genetic Consequences of Tuber Versus Seed Sampling in Two Wild Potato Species Indigenous to the USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wild potatoes reproduce in the wild (in situ) clonally by tubers or sexually by seeds. This study used model populations to assess the genetic consequences of sampling in situ tubers or in situ seeds for two indigenous potato species of the USA, Solanum stoloniferum PI 564039 (sto) and Solanum james...

  14. Mating systems, reproductive success, and sexual selection in secretive species: a case study of the western diamond-backed rattlesnake, Crotalus atrox.

    PubMed

    Clark, Rulon W; Schuett, Gordon W; Repp, Roger A; Amarello, Melissa; Smith, Charles F; Herrmann, Hans-Werner

    2014-01-01

    Long-term studies of individual animals in nature contribute disproportionately to our understanding of the principles of ecology and evolution. Such field studies can benefit greatly from integrating the methods of molecular genetics with traditional approaches. Even though molecular genetic tools are particularly valuable for species that are difficult to observe directly, they have not been widely adopted. Here, we used molecular genetic techniques in a 10-year radio-telemetric investigation of the western diamond-backed rattlesnake (Crotalus atrox) for an analysis of its mating system and to measure sexual selection. Specifically, we used microsatellite markers to genotype 299 individuals, including neonates from litters of focal females to ascertain parentage using full-pedigree likelihood methods. We detected high levels of multiple paternity within litters, yet found little concordance between paternity and observations of courtship and mating behavior. Larger males did not father significantly more offspring, but we found evidence for size-specific male-mating strategies, with larger males guarding females for longer periods in the mating seasons. Moreover, the spatial proximity of males to mothers was significantly associated with reproductive success. Overall, our field observations alone would have been insufficient to quantitatively measure the mating system of this population of C. atrox, and we thus urge more widespread adoption of molecular tools by field researchers studying the mating systems and sexual selection of snakes and other secretive taxa. PMID:24598810

  15. Mating Systems, Reproductive Success, and Sexual Selection in Secretive Species: A Case Study of the Western Diamond-Backed Rattlesnake, Crotalus atrox

    PubMed Central

    Clark, Rulon W.; Schuett, Gordon W.; Repp, Roger A.; Amarello, Melissa; Smith, Charles F.; Herrmann, Hans-Werner

    2014-01-01

    Long-term studies of individual animals in nature contribute disproportionately to our understanding of the principles of ecology and evolution. Such field studies can benefit greatly from integrating the methods of molecular genetics with traditional approaches. Even though molecular genetic tools are particularly valuable for species that are difficult to observe directly, they have not been widely adopted. Here, we used molecular genetic techniques in a 10-year radio-telemetric investigation of the western diamond-backed rattlesnake (Crotalus atrox) for an analysis of its mating system and to measure sexual selection. Specifically, we used microsatellite markers to genotype 299 individuals, including neonates from litters of focal females to ascertain parentage using full-pedigree likelihood methods. We detected high levels of multiple paternity within litters, yet found little concordance between paternity and observations of courtship and mating behavior. Larger males did not father significantly more offspring, but we found evidence for size-specific male-mating strategies, with larger males guarding females for longer periods in the mating seasons. Moreover, the spatial proximity of males to mothers was significantly associated with reproductive success. Overall, our field observations alone would have been insufficient to quantitatively measure the mating system of this population of C. atrox, and we thus urge more widespread adoption of molecular tools by field researchers studying the mating systems and sexual selection of snakes and other secretive taxa. PMID:24598810

  16. Complexity and integration in sexual ornamentation: an example with carotenoid and melanin plumage pigmentation

    E-print Network

    Badyaev, Alex

    Complexity and integration in sexual ornamentation: an example with carotenoid and melanin plumage; melanins; modularity; sexual ornaments. Abstract Sexual ornaments often consist of several components mexicanus and common redpoll, Carduelis flammea) and a species with melanin-based sexual ornamentation

  17. 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 ...

  18. Reproducible research in palaeomagnetism

    NASA Astrophysics Data System (ADS)

    Lurcock, Pontus; Florindo, Fabio

    2015-04-01

    The reproducibility of research findings is attracting increasing attention across all scientific disciplines. In palaeomagnetism as elsewhere, computer-based analysis techniques are becoming more commonplace, complex, and diverse. Analyses can often be difficult to reproduce from scratch, both for the original researchers and for others seeking to build on the work. We present a palaeomagnetic plotting and analysis program designed to make reproducibility easier. Part of the problem is the divide between interactive and scripted (batch) analysis programs. An interactive desktop program with a graphical interface is a powerful tool for exploring data and iteratively refining analyses, but usually cannot operate without human interaction. This makes it impossible to re-run an analysis automatically, or to integrate it into a larger automated scientific workflow - for example, a script to generate figures and tables for a paper. In some cases the parameters of the analysis process itself are not saved explicitly, making it hard to repeat or improve the analysis even with human interaction. Conversely, non-interactive batch tools can be controlled by pre-written scripts and configuration files, allowing an analysis to be 'replayed' automatically from the raw data. However, this advantage comes at the expense of exploratory capability: iteratively improving an analysis entails a time-consuming cycle of editing scripts, running them, and viewing the output. Batch tools also tend to require more computer expertise from their users. PuffinPlot is a palaeomagnetic plotting and analysis program which aims to bridge this gap. First released in 2012, it offers both an interactive, user-friendly desktop interface and a batch scripting interface, both making use of the same core library of palaeomagnetic functions. We present new improvements to the program that help to integrate the interactive and batch approaches, allowing an analysis to be interactively explored and refined, then saved as a self-contained configuration which can be re-run without human interaction. PuffinPlot can thus be used as a component of a larger scientific workflow, integrated with workflow management tools such as Kepler, without compromising its capabilities as an exploratory tool. Since both PuffinPlot and the platform it runs on (Java) are Free/Open Source software, even the most fundamental components of an analysis can be verified and reproduced.

  19. Asexual Evolution: Can Species Exist without Sex?

    E-print Network

    Hillis, David

    a reproductive community (a sexual species), which helps keep the organisms in that sexual community similar reproduction and sexual isolation are clearly sufficient explanations to account for the existence of species for a common ecological niche can produce a pattern that mimics sexual species, even in the absence of sex

  20. Pichia dushanensis sp. nov. and Hyphopichia paragotoi sp. nov., two sexual yeast species associated with insects and rotten wood.

    PubMed

    Ren, Yong-Cheng; Liu, Si-Tong; Li, Ying; Hui, Feng-Li

    2015-09-01

    Seven yeast strains were isolated from the gut of insect larvae and decayed wood, which were collected from three localities near Nanyang, Henan Province, China. These strains were identified as two novel species through comparison of sequences in the D1/D2 domains of the large subunit (LSU) rRNA gene and other taxonomic characteristics. Pichia dushanensis sp. nov. was closely related to species in the Pichia clade and produced one to four spheroid ascospores in a deliquescent ascus. The D1/D2 sequence of P. dushanensis sp. nov. differed from its closest relative, Issatchenkia (Pichia) sp. NRRL Y-12824, by 3.6% sequence divergence (16 substitutions and 4 gaps). The species also differed from its four closest known species, Candida rugopelliculosa, Pichia occidentalis, Pichia exigua and Candida phayaonensis, by 4.1-4.4% sequence divergence (22-24 substitutions and 0-2 gaps) in the D1/D2 sequences. Hyphopichia paragotoi sp. nov. belonged to the Hyphopichia clade, and its nearest phylogenetic neighbours were Candida gotoi, Candida pseudorhagii, Candida rhagii and Hyphopichia heimii with 3.2-4.2% sequence divergence (16-21 substitutions and 1 gap) in the D1/D2 sequences. In comparison with previously established species, H. paragotoi sp. nov. formed one hat-shaped ascospore in a persistent ascus. The type strain of P. dushanensis sp. nov. is NYNU 14658(T) (?= CICC 33049(T) = CBS 13912(T)), and the type strain of H. paragotoi sp. nov. is NYNU 14666(T) (?= CICC 33048(T) = CBS 13913(T)). PMID:25999593

  1. Genetic Architecture of Sexual Dimorphism in Humans.

    PubMed

    Rigby, Nichole; Kulathinal, Rob J

    2015-10-01

    Males and females differ across a broad spectrum of morphological, physiological, and behavioral characters. In fact, sexually dimorphic traits typically contribute the largest component of phenotypic variance in most taxa that use sex to reproduce. However, we know very little about the mechanisms that maintain these dimorphic states and how these sexually dimorphic traits evolve. Here, we review our current knowledge of the underlying genetic basis of sexual dimorphism in humans. First, we briefly review the etiology of sex differences starting from sex determination's initial switch early in embryogenesis. We then survey recent sex-biased transcriptomic expression literature in order to provide additional insight into the landscape of sex-biased gene expression in both gonadal and non-gonadal tissues: from overall prevalence to tissue specificity to conservation across species. Finally, we discuss implications of sex-biased genetic architecture to human health and disease in light of the National Institute of Health's recently proposed initiative to promote study samples from both sexes. PMID:25740260

  2. Reproducible Experiment Platform

    E-print Network

    Likhomanenko, Tatiana; Baranov, Alexander; Khairullin, Egor; Ustyuzhanin, Andrey

    2015-01-01

    Data analysis in fundamental sciences nowadays is an essential process that pushes frontiers of our knowledge and leads to new discoveries. At the same time we can see that complexity of those analyses increases fast due to a)~enormous volumes of datasets being analyzed, b)~variety of techniques and algorithms one have to check inside a single analysis, c)~distributed nature of research teams that requires special communication media for knowledge and information exchange between individual researchers. There is a lot of resemblance between techniques and problems arising in the areas of industrial information retrieval and particle physics. To address those problems we propose Reproducible Experiment Platform (REP), a software infrastructure to support collaborative ecosystem for computational science. It is a Python based solution for research teams that allows running computational experiments on shared datasets, obtaining repeatable results, and consistent comparisons of the obtained results. We present s...

  3. Long-Term Species, Sexual and Individual Variations in Foraging Strategies of Fur Seals Revealed by Stable Isotopes in Whiskers

    PubMed Central

    Kernaléguen, Laëtitia; Cazelles, Bernard; Arnould, John P. Y.; Richard, Pierre; Guinet, Christophe; Cherel, Yves

    2012-01-01

    Background Individual variations in the use of the species niche are an important component of diversity in trophic interactions. A challenge in testing consistency of individual foraging strategy is the repeated collection of information on the same individuals. Methodology/Principal Findings The foraging strategies of sympatric fur seals (Arctocephalus gazella and A. tropicalis) were examined using the stable isotope signature of serially sampled whiskers. Most whiskers exhibited synchronous ?13C and ?15N oscillations that correspond to the seal annual movements over the long term (up to 8 years). ?13C and ?15N values were spread over large ranges, with differences between species, sexes and individuals. The main segregating mechanism operates at the spatial scale. Most seals favored foraging in subantarctic waters (where the Crozet Islands are located) where they fed on myctophids. However, A. gazella dispersed in the Antarctic Zone and A. tropicalis more in the subtropics. Gender differences in annual time budget shape the seal movements. Males that do not perform any parental care exhibited large isotopic oscillations reflecting broad annual migrations, while isotopic values of females confined to a limited foraging range during lactation exhibited smaller changes. Limited inter-individual isotopic variations occurred in female seals and in male A. tropicalis. In contrast, male A. gazella showed large inter-individual variations, with some males migrating repeatedly to high-Antarctic waters where they fed on krill, thus meaning that individual specialization occurred over years. Conclusions/Significance Whisker isotopic signature yields unique long-term information on individual behaviour that integrates the spatial, trophic and temporal dimensions of the ecological niche. The method allows depicting the entire realized niche of the species, including some of its less well-known components such as age-, sex-, individual- and migration-related changes. It highlights intrapopulation heterogeneity in foraging strategies that could have important implications for likely demographic responses to environmental variability. PMID:22431988

  4. Internet Sexualities

    NASA Astrophysics Data System (ADS)

    Döring, Nicola

    The term “internet sexuality” (or OSA, online sexual activities) refers to sexual-related content and activities observable on the internet (cf. Adams, Oye, & Parker, 2003; Cooper, McLoughlin, & Campbell, 2000; Leiblum & Döring, 2002). It designates a variety of sexual phenomena (e.g., pornography, sex education, sexual contacts) related to a wide spectrum of online services and applications (e.g., websites, online chat rooms, peer-to-peer networks). If an even broader range of computer networks - such as the Usenet or bulletin board systems - is included in this extensional definition, one speaks of “online sexuality” or “cybersexuality.”

  5. Epigenetic variation in asexually reproducing organisms.

    PubMed

    Verhoeven, Koen J F; Preite, Veronica

    2014-03-01

    The role that epigenetic inheritance can play in adaptation may differ between sexuals and asexuals because (1) the dynamics of adaptation differ under sexual and asexual reproduction and the opportunities offered by epigenetic inheritance may affect these dynamics differently; and (2) in asexual reproduction epigenetic reprogramming mechanisms that are associated with meiosis can be bypassed, which could promote the buildup of epigenetic variation in asexuals. Here, we evaluate current evidence for an epigenetic contribution to adaptation in asexuals. We argue that two aspects of epigenetic variation should have particular relevance for asexuals, namely epigenetics-mediated phenotypic plasticity within and between generations, and heritable variation via stochastic epimutations. An evaluation of epigenetic reprogramming mechanisms suggests that some, but not all, forms of asexual reproduction enhance the likelihood of stable transmission of epigenetic marks across generations compared to sexual reproduction. However, direct tests of these predicted sexual-asexual differences are virtually lacking. Stable transmission of DNA methylation, transcriptomes, and phenotypes from parent to clonal offspring are demonstrated in various asexual species, and clonal genotypes from natural populations show habitat-specific DNA methylation. We discuss how these initial observations can be extended to demonstrate an epigenetic contribution to adaptation. PMID:24274255

  6. Increased reproductive effort results in male-biased offspring sex ratio: an experimental study in a species with reversed sexual size dimorphism.

    PubMed

    Kalmbach, E; Nager, R G; Griffiths, R; Furness, R W

    2001-10-22

    Adaptive sex-ratio theory predicts that parents should overproduce the more beneficial offspring sex. Based on a recent experimental study of lesser black-backed gulls, we tested this hypothesis with the great skua, Catharacta skua, a bird species closely related to gulls but where females are the larger sex. When in poor body condition, the gulls overproduced daughters, the smaller and more viable sex under those circumstances. To discriminate between a mandatory physiological overproduction of female (i.e. non-male) eggs versus the overproduction of the smaller and presumably more viable sex, we conducted an egg-removal experiment with the great skua. Since the males are smaller, larger size and being male are separated. Through egg removal we induced females to increase egg production effort. Eggs were sexed using a DNA-based technique. Manipulated pairs produced a significant male bias at the end of the extended laying sequence, while the sex ratio in the control group did not differ from unity. Our results present an example of facultative sex-ratio manipulation and support the hypothesis that in sexually dimorphic birds parents overproduce the smaller sex under adverse conditions. PMID:11600083

  7. Sexual Abuse

    MedlinePLUS

    ... form of non-consensual physical contact. It includes rape, molestation, or any sexual conduct with a person ... more? "Speaking the unspeakable: An interview about elder sexual assault with Holly Ramsey-Klawsnik, Ph.D" in nexus , ...

  8. Sexual Health

    MedlinePLUS

    ... for Kids for Teens Teens Home Body Mind Sexual Health Food & Fitness Diseases & Conditions Infections Q&A School & ... Snacking Losing Weight Safely Learn the facts about sexual health with articles about puberty, menstruation, infections, and just ...

  9. Sexual Health

    MedlinePLUS

    ... have or enjoy sex in both men and women. Factors that can affect sexual health include Fear of unplanned pregnancy Concerns about infertility Sexually transmitted diseases Chronic diseases such as cancer or heart disease Medicines that affect sexual desire or performance

  10. Social implications of the battle of the sexes: sexual harassment disrupts female sociality and social recognition.

    PubMed

    Darden, Safi K; James, Richard; Ramnarine, Indar W; Croft, Darren P

    2009-07-22

    Across sexually reproducing species, males and females are in conflict over the control of reproduction. At the heart of this conflict in a number of taxa is male harassment of females for mating opportunities and female strategies to avoid this harassment. One neglected consequence that may result from sexual harassment is the disruption of important social associations. Here, we experimentally manipulate the degree of sexual harassment that wild female guppies (Poecilia reticulata) experience by establishing replicated, semi-natural pools with different population sex ratios. We quantify the effects of sexual harassment on female social structure and the development of social recognition among females. When exposed to sexual harassment, we found that females had more disparate social networks with limited repeated interactions when compared to females that did not experience male harassment. Furthermore, females that did not experience harassment developed social recognition with familiar individuals over an 8-day period, whereas females that experienced harassment did not, an effect we suggest is due to disruption of association patterns. These results show that social network structure and social recognition can be affected by sexual harassment, an effect that will be relevant across taxonomic groups and that we predict will have fitness consequences for females. PMID:19386653

  11. Reproducibility in a multiprocessor system

    SciTech Connect

    Bellofatto, Ralph A; Chen, Dong; Coteus, Paul W; Eisley, Noel A; Gara, Alan; Gooding, Thomas M; Haring, Rudolf A; Heidelberger, Philip; Kopcsay, Gerard V; Liebsch, Thomas A; Ohmacht, Martin; Reed, Don D; Senger, Robert M; Steinmacher-Burow, Burkhard; Sugawara, Yutaka

    2013-11-26

    Fixing a problem is usually greatly aided if the problem is reproducible. To ensure reproducibility of a multiprocessor system, the following aspects are proposed; a deterministic system start state, a single system clock, phase alignment of clocks in the system, system-wide synchronization events, reproducible execution of system components, deterministic chip interfaces, zero-impact communication with the system, precise stop of the system and a scan of the system state.

  12. Clock genes and their genomic distributions in three species of salmonid fishes: Associations with genes regulating sexual maturation and cell cycling

    PubMed Central

    2010-01-01

    Background Clock family genes encode transcription factors that regulate clock-controlled genes and thus regulate many physiological mechanisms/processes in a circadian fashion. Clock1 duplicates and copies of Clock3 and NPAS2-like genes were partially characterized (genomic sequencing) and mapped using family-based indels/SNPs in rainbow trout (RT)(Oncorhynchus mykiss), Arctic charr (AC)(Salvelinus alpinus), and Atlantic salmon (AS)(Salmo salar) mapping panels. Results Clock1 duplicates mapped to linkage groups RT-8/-24, AC-16/-13 and AS-2/-18. Clock3/NPAS2-like genes mapped to RT-9/-20, AC-20/-43, and AS-5. Most of these linkage group regions containing the Clock gene duplicates were derived from the most recent 4R whole genome duplication event specific to the salmonids. These linkage groups contain quantitative trait loci (QTL) for life history and growth traits (i.e., reproduction and cell cycling). Comparative synteny analyses with other model teleost species reveal a high degree of conservation for genes in these chromosomal regions suggesting that functionally related or co-regulated genes are clustered in syntenic blocks. For example, anti-müllerian hormone (amh), regulating sexual maturation, and ornithine decarboxylase antizymes (oaz1 and oaz2), regulating cell cycling, are contained within these syntenic blocks. Conclusions Synteny analyses indicate that regions homologous to major life-history QTL regions in salmonids contain many candidate genes that are likely to influence reproduction and cell cycling. The order of these genes is highly conserved across the vertebrate species examined, and as such, these genes may make up a functional cluster of genes that are likely co-regulated. CLOCK, as a transcription factor, is found within this block and therefore has the potential to cis-regulate the processes influenced by these genes. Additionally, clock-controlled genes (CCGs) are located in other life-history QTL regions within salmonids suggesting that at least in part, trans-regulation of these QTL regions may also occur via Clock expression. PMID:20670436

  13. Female sexuality.

    PubMed

    Rao, T S Sathyanarana; Nagaraj, Anil Kumar M

    2015-07-01

    Sex is a motive force bringing a man and a woman into intimate contact. Sexuality is a central aspect of being human throughout life and encompasses sex, gender identities and roles, sexual orientation, eroticism, pleasure, intimacy, and reproduction. Sexuality is experienced and expressed in thoughts, fantasies, desires, beliefs, attitudes, values, behaviors, practices, roles and relationships. Though generally, women are sexually active during adolescence, they reach their peak orgasmic frequency in their 30 s, and have a constant level of sexual capacity up to the age of 55 with little evidence that aging affects it in later life. Desire, arousal, and orgasm are the three principle stages of the sexual response cycle. Each stage is associated with unique physiological changes. Females are commonly affected by various disorders in relation to this sexual response cycle. The prevalence is generally as high as 35-40%. There are a wide range of etiological factors like age, relationship with a partner, psychiatric and medical disorders, psychotropic and other medication. Counseling to overcome stigma and enhance awareness on sexuality is an essential step in management. There are several effective psychological and pharmacological therapeutic approaches to treat female sexual disorders. This article is a review of female sexuality. PMID:26330647

  14. Female sexuality

    PubMed Central

    Rao, T.S. Sathyanarana; Nagaraj, Anil Kumar M.

    2015-01-01

    Sex is a motive force bringing a man and a woman into intimate contact. Sexuality is a central aspect of being human throughout life and encompasses sex, gender identities and roles, sexual orientation, eroticism, pleasure, intimacy, and reproduction. Sexuality is experienced and expressed in thoughts, fantasies, desires, beliefs, attitudes, values, behaviors, practices, roles and relationships. Though generally, women are sexually active during adolescence, they reach their peak orgasmic frequency in their 30 s, and have a constant level of sexual capacity up to the age of 55 with little evidence that aging affects it in later life. Desire, arousal, and orgasm are the three principle stages of the sexual response cycle. Each stage is associated with unique physiological changes. Females are commonly affected by various disorders in relation to this sexual response cycle. The prevalence is generally as high as 35–40%. There are a wide range of etiological factors like age, relationship with a partner, psychiatric and medical disorders, psychotropic and other medication. Counseling to overcome stigma and enhance awareness on sexuality is an essential step in management. There are several effective psychological and pharmacological therapeutic approaches to treat female sexual disorders. This article is a review of female sexuality. PMID:26330647

  15. [Adolescent's sexuality].

    PubMed

    Roynet, D

    2007-09-01

    Adolescence, period hinge between child and adulthood, is one period of great psychic and physiological vulnerability. The autonomisation, the sexualisation of feelings, the step to on active sexuality are potential situations of conflicts, dangers and various risks to reach and discover its own identity. Attacks against masculinity or femininity, sexual traumas, wounds in the relations (rejects, humiliation, abandon, ...) could have important consequences on sexual health of the adult in becoming. PMID:17958032

  16. Compulsory sexuality.

    PubMed

    Emens, Elizabeth F

    2014-02-01

    Asexuality is an emerging identity category that challenges the common assumption that everyone is defined by some type of sexual attraction. Asexuals--those who report feeling no sexual attraction to others--constitute one percent of the population, according to one prominent study. In recent years, some individuals have begun to identify as asexual and to connect around their experiences interacting with a sexual society. Asexuality has also become a protected classification under the antidiscrimination law of one state and several localities, but legal scholarship has thus far neglected the subject. This Article introduces asexuality to the legal literature as a category of analysis, an object of empirical study, and a phenomenon of medical science. It then offers a close examination of the growing community of self-identified asexuals. Asexual identity has revealing intersections with the more familiar categories of gender, sexual orientation, and disability, and inspires new models for understanding sexuality. Thinking about asexuality also sheds light on our legal system. Ours is arguably a sexual law, predicated on the assumption that sex is important. This Article uses asexuality to develop a framework for identifying the ways that law privileges sexuality. Across various fields, these interactions include legal requirements of sexual activity, special carve-outs to shield sexuality from law, legal protections from others' sexuality, and legal protections for sexual identity. Applying this framework, the Article traces several ways that our sexual law burdens, and occasionally benefits, asexuals. This Article concludes by closely examining asexuality's prospects for broader inclusion into federal, state, and local antidiscrimination laws. PMID:24654293

  17. Sexual dimorphism in flowering plants.

    PubMed

    Barrett, Spencer C H; Hough, Josh

    2013-01-01

    Among dioecious flowering plants, females and males often differ in a range of morphological, physiological, and life-history traits. This is referred to as sexual dimorphism, and understanding why it occurs is a central question in evolutionary biology. Our review documents a range of sexually dimorphic traits in angiosperm species, discusses their ecological consequences, and details the genetic and evolutionary processes that drive divergence between female and male phenotypes. We consider why sexual dimorphism in plants is generally less well developed than in many animal groups, and also the importance of sexual and natural selection in contributing to differences between the sexes. Many sexually dimorphic characters, including both vegetative and flowering traits, are associated with differences in the costs of reproduction, which are usually greater in females, particularly in longer-lived species. These differences can influence the frequency and distribution of females and males across resource gradients and within heterogeneous environments, causing niche differences and the spatial segregation of the sexes. The interplay between sex-specific adaptation and the breakdown of between-sex genetic correlations allows for the independent evolution of female and male traits, and this is influenced in some species by the presence of sex chromosomes. We conclude by providing suggestions for future work on sexual dimorphism in plants, including investigations of the ecological and genetic basis of intraspecific variation, and genetic mapping and expression studies aimed at understanding the genetic architecture of sexually dimorphic trait variation. PMID:23183260

  18. SEXUAL MISCONDUCT = Sexual harassment, gender discrimination or bias, sexual assault, rape, stalking or

    E-print Network

    Dennett, Daniel

    SEXUAL MISCONDUCT = Sexual harassment, gender discrimination or bias, sexual assault, rape. SEXUAL MISCONDUCT = Sexual harassment, gender discrimination or bias, sexual assault, rape, stalking inappropriate sexual materials in a location where others can view them. Sexual assault, rape, or attempted

  19. Triploid planarian reproduces truly bisexually with euploid gametes produced through a different meiotic system between sex.

    PubMed

    Chinone, Ayako; Nodono, Hanae; Matsumoto, Midori

    2014-06-01

    Although polyploids are common among plants and some animals, polyploidization often causes reproductive failure. Triploids, in particular, are characterized by the problems of chromosomal pairing and segregation during meiosis, which may cause aneuploid gametes and results in sterility. Thus, they are generally considered to reproduce only asexually. In the case of the Platyhelminthes Dugesia ryukyuensis, populations with triploid karyotypes are normally found in nature as both fissiparous and oviparous triploids. Fissiparous triploids can also be experimentally sexualized if they are fed sexual planarians, developing both gonads and other reproductive organs. Fully sexualized worms begin reproducing by copulation rather than fission. In this study, we examined the genotypes of the offspring obtained by breeding sexualized triploids and found that the offspring inherited genes from both parents, i.e., they reproduced truly bisexually. Furthermore, meiotic chromosome behavior in triploid sexualized planarians differed significantly between male and female germ lines, in that female germ line cells remained triploid until prophase I, whereas male germ line cells appeared to become diploid before entry into meiosis. Oocytes at the late diplotene stage contained not only paired bivalents but also unpaired univalents that were suggested to produce diploid eggs if they remained in subsequent processes. Triploid planarians may therefore form euploid gametes by different meiotic systems in female and male germ lines and thus are be able to reproduce sexually in contrast to many other triploid organisms. PMID:24402417

  20. Sex in Cheese: Evidence for Sexuality in the Fungus Penicillium roqueforti

    PubMed Central

    Ropars, Jeanne; Dupont, Joëlle; Fontanillas, Eric; Rodríguez de la Vega, Ricardo C.; Malagnac, Fabienne; Coton, Monika; Giraud, Tatiana; López-Villavicencio, Manuela

    2012-01-01

    Although most eukaryotes reproduce sexually at some moment of their life cycle, as much as a fifth of fungal species were thought to reproduce exclusively asexually. Nevertheless, recent studies have revealed the occurrence of sex in some of these supposedly asexual species. For industrially relevant fungi, for which inoculums are produced by clonal-subcultures since decades, the potentiality for sex is of great interest for strain improvement strategies. Here, we investigated the sexual capability of the fungus Penicillium roqueforti, used as starter for blue cheese production. We present indirect evidence suggesting that recombination could be occurring in this species. The screening of a large sample of strains isolated from diverse substrates throughout the world revealed the existence of individuals of both mating types, even in the very same cheese. The MAT genes, involved in fungal sexual compatibility, appeared to evolve under purifying selection, suggesting that they are still functional. The examination of the recently sequenced genome of the FM 164 cheese strain enabled the identification of the most important genes known to be involved in meiosis, which were found to be highly conserved. Linkage disequilibria were not significant among three of the six marker pairs and 11 out of the 16 possible allelic combinations were found in the dataset. Finally, the detection of signatures of repeat induced point mutations (RIP) in repeated sequences and transposable elements reinforces the conclusion that P. roqueforti underwent more or less recent sex events. In this species of high industrial importance, the induction of a sexual cycle would open the possibility of generating new genotypes that would be extremely useful to diversify cheese products. PMID:23185400

  1. Towards reproducible, scalable lateral molecular electronic devices

    SciTech Connect

    Durkan, Colm Zhang, Qian

    2014-08-25

    An approach to reproducibly fabricate molecular electronic devices is presented. Lateral nanometer-scale gaps with high yield are formed in Au/Pd nanowires by a combination of electromigration and Joule-heating-induced thermomechanical stress. The resulting nanogap devices are used to measure the electrical properties of small numbers of two different molecular species with different end-groups, namely 1,4-butane dithiol and 1,5-diamino-2-methylpentane. Fluctuations in the current reveal that in the case of the dithiol molecule devices, individual molecules conduct intermittently, with the fluctuations becoming more pronounced at larger biases.

  2. Progesterone and prostaglandin F2? induce species-typical female preferences for male sexual displays in Cope's gray treefrog (Hyla chrysoscelis).

    PubMed

    Ward, Jessica L; Love, Elliot K; Baugh, Alexander T; Gordon, Noah M; Tanner, Jessie C; Bee, Mark A

    2015-12-01

    Endocrine systems play critical roles in facilitating sexual behavior in seasonally breeding vertebrates. Much of the research exploring this topic has focused on the endocrine correlates of signaling behavior in males and sexual proceptivity in females. What is less understood is how hormones promote the expression of the often complex and highly selective set of stimulus-response behaviors that are observed in naturally breeding animals. In female frogs, phonotaxis is a robust and sensitive bioassay of mate choice and is exhibited by gravid females during the breeding season. In stark contrast, females exhibit low phonotactic responsiveness outside the breeding season, but the administration of hormones can induce sexual proceptivity. Here we test the hypothesis that manipulation of a minimal set of reproductive hormones-progesterone and prostaglandin F2?-are capable of evoking not only proceptive behavior in non-breeding females, but also the patterns of intraspecific selectivity for male sexual displays observed in gravid females tested during the breeding season. Specifically, we investigated whether preferences for faster call rates, longer call durations, and higher call efforts were similar between breeding and hormone-treated females of Cope's gray treefrog (Hyla chrysoscelis). Hormone injections induced patterns of selective phonotaxis in non-breeding females that were remarkably similar to those observed in breeding females. These results suggest that there may be an important contribution of hormonal pleiotropy in regulating this complex, acoustically-guided sexual behavior. Our findings also support the idea that hormonal induction could be used to evaluate hypotheses about selective mate choice, and its underlying mechanisms, using non-breeding females. PMID:26454212

  3. Improved Astronomical Image Reproducing Techniques

    NASA Astrophysics Data System (ADS)

    Jeon, Young-Beom

    1993-12-01

    Astronomical plates have a very large density range(dynamical range). Many exposed astronomical photographic plates do not provide detailed structures for very high densities, and some include hidden images for very low densities. The former can be fixed through 'Unsharp Masking' technique and the latter through 'Image Amplification' technique. Besides, we can find intrinsic colors of celestial bodies through 'Tri Color Composition' technique. Images of several plates which were observed from Sobaek Observatory with 61cm telescope are reproduced by the three kinds of image reproducing techniques. As reproduced image examples, we display an Orion nebula and a waxing crescent moon images through unsharp masking technique and an M81 image through image amplification technique. An Orion nebula and a Dumbbell nebula images are also given as results of tri color composition technique.

  4. Sexual Health

    MedlinePLUS

    ... our e-newsletter! Aging & Health A to Z Sexual Health Basic Facts & Information All adults, including older people, ... the opportunity to enjoy a satisfying and fulfilling sex life. In fact, most of them do, even ...

  5. Healthy Sexuality

    MedlinePLUS Videos and Cool Tools

    ... viewing this embedded video, please click here . Transcript Sex and sexuality are important issues for many people, regardless of their age, sex, or gender. Although many people are embarrassed or ...

  6. Teenage Sexuality

    MedlinePLUS

    ... Pediatrician Ages & Stages Prenatal Baby Toddler Preschool Gradeschool Teen Dating & Sex Fitness Nutrition Driving Safety School Substance Abuse Young Adult Healthy Children > Ages & Stages > Teen > Dating & Sex > Teenage Sexuality Ages & Stages Listen Espańol Text Size ...

  7. Monte Carlo simulations of sexual reproduction

    NASA Astrophysics Data System (ADS)

    Stauffer, D.; de Oliveira, P. M. C.; de Oliveira, S. Moss; dos Santos, R. M. Zorzenon

    1996-02-01

    Modifying the Redfield model of sexual reproduction and the Penna model of biological aging, we compare reproduction with and without recombination in age-structured populations. In constrast to Redfield and in agreement with Bernardes we find sexual reproduction to be preferred to asexual one. In particular, the presence of old but still reproducing males helps the survival of younger females beyond their reproductive age.

  8. Sexual sadism in sexual offenders and sexually motivated homicide.

    PubMed

    Briken, Peer; Bourget, Dominique; Dufour, Mathieu

    2014-06-01

    This article gives a clinically oriented overview of forensically relevant forms of sexual sadism disorder and its specific relationship to sexual homicide. In sexual homicide perpetrators, peculiar patterns of sexual sadism may be a motivational pathway to kill. Sexual sadism increases the risk for reoffending in sexual offenders. Through psychotherapy and pharmacological interventions, treatment of sadistic sex offenders has to consider special characteristics that may be different from those of nonsadistic sex offenders. Many of these offenders share a combination of sexual sadistic motives and an intact self-regulation, sometimes combined with a high level of sexual preoccupation. PMID:24877708

  9. SEXUAL MISCONDUCT/SEXUAL ASSAULT POLICY

    E-print Network

    Dennett, Daniel

    Sexual Misconduct to seek assistance from counseling or mental health services and/or to seek medicalSEXUAL MISCONDUCT/SEXUAL ASSAULT POLICY Office of Equal Opportunity Purpose: To establish a work and educational environment at Tufts University that is free from Sexual Misconduct, which includes sexual

  10. Apomictic and sexual pearl millet X Pennisetum squamulatum hybrids

    SciTech Connect

    Dujardin, M.; Hanna, W.W.

    1983-01-01

    Pennisetum squamulatum Fresen, an apomictic East African grass (2n = 54) was crossed to tetraploid (2n = 28) sexual pearl millet, P. americanum L. Leeke to study the potential for germplasm exchange. Twenty interspecific hybrids (2n = 41) with 14 pearl millet and 27 P. squamulatum chromosomes were obtained. All resembled P. squamulatum in perennial growth habit and inflorescence characteristics and resembled pearl millet in leafiness and pencillate anther tips. Seventeen of these hybrids were more vigorous than either parent. The most common chromosome association at metaphase I was 18 bivalents plus 5 univalents. At anaphase I and telophase I laggards, fragments, and unequal chromosome distribution were observed. Fifteen of 17 interspecific hybrids reproduced by facultative apomixis, one was sexual and one was an obligate apomict. Ovules with aposporous embryo sacs ranged from 1 to 93% in facultative apomictic plants. Morphological characteristics and chromosome numbers of open-pollinated progeny from the apomictic interspecific hybrid were identical to those of the seed parent indicating obligate apomictic reproduction. Both sexual and apomictic hybrids were partially male fertile with pollen stainability ranging from 29 percent to 79 percent and seed-set ranging from 1 to 60 seed per inflorescence under open-pollination. Development of fertile apomictic pearl millet-P. squamulatum interspecific hybrids appears to be a very useful tool for the transfer of genes for apomixis from the wild species to pearl millet.

  11. Reproducible Bioinformatics Research for Biologists

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book chapter describes the current Big Data problem in Bioinformatics and the resulting issues with performing reproducible computational research. The core of the chapter provides guidelines and summaries of current tools/techniques that a noncomputational researcher would need to learn to pe...

  12. Healthy Aging -- Sexual Health

    MedlinePLUS

    ... Healthy Aging This information in Spanish ( en espańol ) 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 ...

  13. Sexually Transmitted Diseases (STDs)

    MedlinePLUS

    ... link in the menu on the left. Common Names Sexually transmitted diseases STDs Sexually transmitted infections STIs Medical or Scientific Names Sexually transmitted diseases Sexually transmitted infections Last Reviewed: ...

  14. Introduction Animals are naturally selected to reproduce at times of year

    E-print Network

    Katti, Madhusudan

    3786 Introduction Animals are naturally selected to reproduce at times of year when offspring and stop reproduction at different times for different species (the adaptive specialization hypothesis breeding species may not exhibit photorefractoriness. We tested for absolute photorefractoriness in four

  15. Sexual Education and Morality.

    ERIC Educational Resources Information Center

    Spiecker, Ben

    1992-01-01

    Distinguishes five interpretations of sexual education including factual knowledge; self-control; stressing love; sexual training; and sexual morality. Suggests that sexual education should be understood as teaching children the moral tendencies relevant to sexual conduct. Argues that infantile sexual desire is based on a contradiction in terms…

  16. SEXUAL ASSAULT, SEXUAL HARASSMENT, STALKING OR RELATIONSHIP VIOLENCE POLICY

    E-print Network

    McConnell, Terry

    ,domestic or dating violence,stalking,sexual coercion and non-contact sexual abuse such as voyeurism,and sexual and other forms of sexual assault, sexual coercion and non- contact sexual abuse such as voyeurism

  17. Scientific Understanding of Sexual Orientation: Implications for Science Education.

    ERIC Educational Resources Information Center

    Good, Ron; Hafner, Mark; Peebles, Patsye

    2000-01-01

    Discusses sexual orientation using the analogy of handedness. Points out the presence of diverse sexual behavior and homosexuality among living species and focuses on human behavior. Encourages discussions among biology teachers on the origins of sexual orientation. (Contains 27 references.) (YDS)

  18. Unrecognized coral species diversity masks differences in functional ecology

    PubMed Central

    Boulay, Jennifer N.; Hellberg, Michael E.; Cortés, Jorge; Baums, Iliana B.

    2014-01-01

    Porites corals are foundation species on Pacific reefs but a confused taxonomy hinders understanding of their ecosystem function and responses to climate change. Here, we show that what has been considered a single species in the eastern tropical Pacific, Porites lobata, includes a morphologically similar yet ecologically distinct species, Porites evermanni. While P. lobata reproduces mainly sexually, P. evermanni dominates in areas where triggerfish prey on bioeroding mussels living within the coral skeleton, thereby generating asexual coral fragments. These fragments proliferate in marginal habitat not colonized by P. lobata. The two Porites species also show a differential bleaching response despite hosting the same dominant symbiont subclade. Thus, hidden diversity within these reef-builders has until now obscured differences in trophic interactions, reproductive dynamics and bleaching susceptibility, indicative of differential responses when confronted with future climate change. PMID:24335977

  19. Sexual Reproduction in a Simple Growth Population Model

    NASA Astrophysics Data System (ADS)

    Lemos, Carlos Gentil Oro; Santos, Marcio

    2012-05-01

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

  20. Harvard University Sexual Harassment and

    E-print Network

    Chen, Yiling

    , humiliating, or sexually offensive working environment. Workplace sexual harassment includes behavior or sexually suggestive comments, jokes, innuendoes or gestures; Displaying sexually suggestive objects

  1. Distribution of Phoxinus eos, Phoxinus neogaeus, and Their Asexually-Reproducing Hybrids (Pisces: Cyprinidae)

    E-print Network

    Sokolowski, Marla

    -glacial dispersal, or to differences in ecology. These results suggest that asexual reproduction is a successful the reasons why asexual reproduction is rare among vertebrates, and more generally how asexual and sexualDistribution of Phoxinus eos, Phoxinus neogaeus, and Their Asexually-Reproducing Hybrids (Pisces

  2. The evolution of sexual dimorphism in parasitic cuckoos: sexual selection or coevolution?

    E-print Network

    Krüger, Oliver

    The evolution of sexual dimorphism in parasitic cuckoos: sexual selection or coevolution? O. Kru. The cuckoos (family Cuculidae) provide an exceptional case in which both sexes of many species are freed from the burden of parental care but where coevolution between parasitic cuckoos and their hosts also results

  3. [Adolescent sexuality].

    PubMed

    Calero, Juan del Rey

    2010-01-01

    The social Adolescent features are insecurity, narcissism, eroticism, more impetuosity than reason. 1/3 of adolescents have risk behaviour for health. The pregnancy rate in adolescent are 9/1,000 (11,720, the abort about 50 %). The total abort (2009) were 114,480. Increase the rate of 8,4 (1990) to 14,6/ 1,000 (2009). The sexual education fails. The consulting about contraceptives get pregnancy of the OR 3,2, condom OR 2,7. The adolescent are influenced in his matter: oeer have 70-75 % of influence, mother 30-40 %, father 15 %, for yhe environment and education Cyberspace access to information: 33 % exposed to unwanted sexual materials, 1 in 7 solicited sexual online. The argument have 4 central topic: Morality and Responsibility, Desire (responsibility vs gratification), Danger (fear related to pregnancy and STD/VIH), and Victimization. The prevention of STD: so called safe sex, delayed, and abstinence, Prevention HPV vaccine. The information is not enough, are necessary personal integral formation in values as self control, abstinence, mutual respect, responsibility, reasonable decisions. PMID:21877398

  4. Toddlers and Sexual Behavior

    MedlinePLUS

    Pediatrics Common Questions, Quick Answers Toddlers and Sexual Behavior Donna D'Alessandro, M.D. Lindsay Huth, B. ... problem or sexual abuse. What kind of sexual behaviors are okay? Masturbation in toddlers is usually nothing ...

  5. Sexuality and Down Syndrome

    MedlinePLUS

    ... Down Syndrome Managing Behavior Sexuality Sexuality & Down Syndrome Social and Sexual Education Recreation & Friendship Education Education & Down Syndrome Schooling from Preschool to Age 21 Implementing Inclusion College & Postsecondary Options Looking for Postsecondary Education O' ...

  6. Your Sexual Health

    MedlinePLUS

    ... AQ FREQUENTLY ASKED QUESTIONS FAQ072 WOMEN’S HEALTH Your Sexual Health • What causes sexual problems in women? • What are ... another term for interest in and desire for sex) and sexual activity sometimes decrease with age. This ...

  7. Tackling reproducibility in academic preclinical drug discovery.

    PubMed

    Frye, Stephen V; Arkin, Michelle R; Arrowsmith, Cheryl H; Conn, P Jeffrey; Glicksman, Marcie A; Hull-Ryde, Emily A; Slusher, Barbara S

    2015-11-01

    The reproducibility of biomedical research on novel drug targets has become suspect. Here, we highlight how drug discovery centres embedded in academic institutions, but with a translational imperative, can help address this reproducibility crisis. PMID:26388229

  8. Five selfish reasons to work reproducibly.

    PubMed

    Markowetz, Florian

    2015-01-01

    And so, my fellow scientists: ask not what you can do for reproducibility; ask what reproducibility can do for you! Here, I present five reasons why working reproducibly pays off in the long run and is in the self-interest of every ambitious, career-oriented scientist. PMID:26646147

  9. of sexual harassment and discrimination

    E-print Network

    , Gender, Religion, Color, Nation Origin, Age, Sexual Orientation, Gender Identity, Gender Expressionof sexual harassment and discrimination Equal Opportunity & Title IX Office University of Nevada, Reno #12;Today's Conversation will Include the Following: Sexual Content Sexual Harassment Sexual

  10. SEXUAL MISCONDUCT = Sexual harassment, gender discrimination or bias, sexual assault, rape, stalking or

    E-print Network

    Dennett, Daniel

    SEXUAL MISCONDUCT = Sexual harassment, gender discrimination or bias, sexual assault, rape. SEXUAL MISCONDUCT = Sexual harassment, gender discrimination or bias, sexual assault, rape, stalking materials in a location where others can view them. Sexual assault, rape, or attempted rape. 3 #12;4 Sexual

  11. 252 | APRIL 2002 | VOLUME 3 www.nature.com/reviews/genetics also introduces the risk of sexually transmitted diseases

    E-print Network

    Otto, Sarah

    , such as the infamous twofold cost of sex. In sexual reproduction, the unit of reproduction is the couple, whereas in asexual reproduction it is the individual. Unless the sexually reproducing couple can produce twice reproductive output per capita.At one extreme,if sexual couples and asexual individuals produce the same

  12. Female homosexual behavior and inter-sexual mate competition in Japanese macaques: possible implications for sexual selection theory.

    PubMed

    Vasey, Paul L; Leca, Jean-Baptiste; Gunst, Noëlle; VanderLaan, Doug P

    2014-10-01

    In this paper, we review research related to female homosexual behavior in Japanese macaques (Macaca fuscata), including our 20-year program of research on this species. Multiple lines of evidence indicate that female homosexual behavior in this species is sexually motivated. In contrast, many sociosexual hypotheses have been tested in relation to female homosexual behavior in Japanese macaques, but none have been supported. Female Japanese macaques sometimes engage in same-sex sexual activity even when motivated opposite-sex alternatives are available. Within this context of mate choice, males compete inter-sexually for opportunities to copulate with females above and beyond any intra-sexual competition that is required. Anecdotal evidence suggests that inter-sexual competition for female sexual partners has been observed in a number of other species, including humans. At present it is unclear whether inter-sexual competition for sexual partners influences patterns of reproduction. Our understanding of sexual selection and the evolution of mating systems may be improved by investigating whether inter-sexual mate competition influences the acquisition and maintenance of reproductive partners in those species in which such interactions occur. PMID:25242104

  13. Molecular barcoding and phylogeography of sexual and asexual freshwater planarians of the genus Dugesia in the Western Mediterranean (Platyhelminthes, Tricladida, Dugesiidae).

    PubMed

    Lázaro, Eva M; Sluys, Ronald; Pala, Maria; Stocchino, Giacinta Angela; Baguńŕ, Jaume; Riutort, Marta

    2009-09-01

    Planarians of the genus Dugesia have a worldwide distribution with high species diversity in the Mediterranean area. In this area, populations with a triploid karyotype that reproduce by fissiparity are exceptionally frequent, outnumbering the sexual populations. This situation poses interesting questions, such as the age of these asexual lineages, whether they all belong to the same species or whether the triploidization event is recurrent, and what factors (climatic, geographical, historical...) explain the prevalence of these asexual forms. However, asexual populations cannot be assigned to a species due to the lack of copulatory apparatus--the main structure used in species identification. In this study, we have developed a DNA barcoding method, based on COI and ITS-1 sequences, which allows the assignment of the fissiparous forms to sexual species. At the same time, phylogenetic analysis from species of the western Mediterranean have unveiled the presence of species with highly differentiated populations alongside species with a wide distribution and almost no genetic variation. The roles of habitat instability, dispersal capacity and human activities are briefly discussed. PMID:19435604

  14. Male sexual harassment alters female social behaviour towards other females.

    PubMed

    Darden, Safi K; Watts, Lauren

    2012-04-23

    Male harassment of females to gain mating opportunities is a consequence of an evolutionary conflict of interest between the sexes over reproduction and is common among sexually reproducing species. Male Trinidadian guppies Poecilia reticulata spend a large proportion of their time harassing females for copulations and their presence in female social groups has been shown to disrupt female-female social networks and the propensity for females to develop social recognition based on familiarity. In this study, we investigate the behavioural mechanisms that may lead to this disruption of female sociality. Using two experiments, we test the hypothesis that male presence will directly affect social behaviours expressed by females towards other females in the population. In experiment one, we tested for an effect of male presence on female shoaling behaviour and found that, in the presence of a free-swimming male guppy, females spent shorter amounts of time with other females than when in the presence of a free-swimming female guppy. In experiment two, we tested for an effect of male presence on the incidence of aggressive behaviour among female guppies. When males were present in a shoal, females exhibited increased levels of overall aggression towards other females compared with female only shoals. Our work provides direct evidence that the presence of sexually harassing males alters female-female social behaviour, an effect that we expect will be recurrent across taxonomic groups. PMID:21976624

  15. Lect. 15: Sexual selection Sexual dimorphism

    E-print Network

    with reproduction) Selection for sexual dimorphism? · Fitness under natural selection: typically same for both sexes Survival ReproductionFitness Selection for sexual dimorphism? · Must act on sexes differently · Process Fitness Sexual selection · Differential reproductive success due to variation among individuals in ability

  16. Sexual selection and mating systems.

    PubMed

    Shuster, Stephen M

    2009-06-16

    Sexual selection is among the most powerful of all evolutionary forces. It occurs when individuals within one sex secure mates and produce offspring at the expense of other individuals within the same sex. Darwin was first to recognize the power of sexual selection to change male and female phenotypes, and, in noting that sexual selection is nonubiquitous, Darwin was also first to recognize the importance of mating system--the "special circumstances" in which reproduction occurs within species. Analyses of mating systems since Darwin have emphasized either the genetic relationships between male and female mating elements, usually among plants, or the numbers of mates males and females may obtain, usually among animals. Combining these schemes yields a quantitative methodology that emphasizes measurement of the sex difference in the variance in relative fitness, as well as phenotypic and genetic correlations underlying reproductive traits that may arise among breeding pairs. Such information predicts the degree and direction of sexual dimorphism within species, it allows the classification of mating systems using existing genetic and life history data, and with information on the spatial and temporal distributions of fertilizations, it may also predict floral morphology in plants. Because this empirical framework identifies selective forces and genetic architectures responsible for observed male-female differences, it compliments discoveries of nucleotide sequence variation and the expression of quantitative traits. Moreover, because this methodology emphasizes the process of evolutionary change, it is easier to test and interpret than frameworks emphasizing parental investment in offspring and its presumed evolutionary outcomes. PMID:19528645

  17. Diagnostic Reproducibility of Hydatidiform Moles

    PubMed Central

    Gupta, Mamta; Vang, Russell; Yemelyanova, Anna V.; Kurman, Robert J.; Li, Fanghong Rose; Maambo, Emily C.; Murphy, Kathleen M.; DeScipio, Cheryl; Thompson, Carol B.; Ronnett, Brigitte M.

    2015-01-01

    Distinction of hydatidiform moles from nonmolar specimens (NMs) and subclassification of hydatidiform moles as complete hydatidiform mole (CHM) and partial hydatidiform mole (PHM) are important for clinical practice and investigational studies; however, diagnosis based solely on morphology is affected by interobserver variability. Molecular genotyping can distinguish these entities by discerning androgenetic diploidy, diandric triploidy, and biparental diploidy to diagnose CHMs, PHMs, and NMs, respectively. Eighty genotyped cases (27 CHMs, 27 PHMs, 26 NMs) were selected from a series of 200 potentially molar specimens previously diagnosed using p57 immunohistochemistry and genotyping. Cases were classified by 6 pathologists (3 faculty level gynecologic pathologists and 3 fellows) on the basis of morphology, masked to p57 immunostaining and genotyping results, into 1 of 3 categories (CHM, PHM, or NM) during 2 diagnostic rounds; a third round incorporating p57 immunostaining results was also conducted. Consensus diagnoses (those rendered by 2 of 3 pathologists in each group) were also determined. Performance of experienced gynecologic pathologists versus fellow pathologists was compared, using genotyping results as the gold standard. Correct classification of CHMs ranged from 59% to 100%; there were no statistically significant differences in performance of faculty versus fellows in any round (P-values of 0.13, 0.67, and 0.54 for rounds 1 to 3, respectively). Correct classification of PHMs ranged from 26% to 93%, with statistically significantly better performance of faculty versus fellows in each round (P-values of 0.04, <0.01, and <0.01 for rounds 1 to 3, respectively). Correct classification of NMs ranged from 31% to 92%, with statistically significantly better performance of faculty only in round 2 (P-values of 1.0, <0.01, and 0.61 for rounds 1 to 3, respectively). Correct classification of all cases combined ranged from 51% to 75% by morphology and 70% to 80% with p57, with statistically significantly better performance of faculty only in round 2 (P-values of 0.69, <0.01, and 0.15 for rounds 1 to 3, respectively). p57 immunostaining significantly improved recognition of CHMs (P<0.01) and had high reproducibility (?=0.93 to 0.96) but had no impact on distinction of PHMs and NMs. Genotyping provides a definitive diagnosis for the ~25% to 50% of cases that are misclassified by morphology, especially those that are also unresolved by p57 immunostaining. PMID:22992698

  18. Reproducible EnzymeReproducible Enzyme Assembly and CatalyticAssembly and Catalytic

    E-print Network

    Rubloff, Gary W.

    Reproducible EnzymeReproducible Enzyme Assembly and CatalyticAssembly and Catalytic Activity Accomplishments #12;Reproducible Enzyme Assembly and CatalyticReproducible Enzyme Assembly and Catalytic Activity in Reusable BioMEMSActivity in Reusable BioMEMS Accomplishment Pro-tagged Pfs enzymes are spatially assembled

  19. Addressing Sexual Harassment

    ERIC Educational Resources Information Center

    Young, Ellie L.; Ashbaker, Betty Y.

    2008-01-01

    This article discusses ways on how to address the problem of sexual harassment in schools. Sexual harassment--simply defined as any unwanted and unwelcome sexual behavior--is a sensitive topic. Merely providing students, parents, and staff members with information about the school's sexual harassment policy is insufficient; schools must take…

  20. Sexuality and the law.

    PubMed

    Portelli, C J

    1998-01-01

    Federal, state, and local laws in the US now govern almost every aspect of sexuality. This includes sexuality at the workplace, sexuality education, adolescent sexuality, access to sexuality information and sexually explicit materials, sexual orientation, and sexually transmitted disease(STD)/HIV transmission. Almost 33% of the US Supreme Court's docket this past term concerned sexuality issues. In contrast to 50 years ago, when sexuality law was confined to the criminal arena, contemporary "sex crimes" primarily relate to nonconsensual and exploitative behaviors. It is time for lawmakers, judges, lawyers, policy analysts, lobbyists, and advocates to realize they cannot legislate or litigate how, when, or why people fall in love. Rather, the role of the law should be to create and preserve models of justice and equality that seek to preserve one's individual rights to privacy and freedom to choose in matters related to one's sexuality. This includes free access to age-appropriate sexuality information, the right to marriage and children regardless of sexual orientation, comprehensive sexuality education that encompasses information about avoiding unwanted pregnancies and HIV/STDs, access to contraception and abortion, protection from sexually abusive or exploitative relationships, and access to sexual health care. PMID:12295182

  1. Sexual behaviour: rapid speciation in an arthropod.

    PubMed

    Mendelson, Tamra C; Shaw, Kerry L

    2005-01-27

    Theory predicts that sexual behaviour in animals can evolve rapidly, accelerating the rate of species formation. Here we estimate the rate of speciation in Laupala, a group of forest-dwelling Hawaiian crickets that is characterized primarily through differences in male courtship song. We find that Laupala has the highest rate of speciation so far recorded in arthropods, supporting the idea that divergence in courtship or sexual behaviour drives rapid speciation in animals. PMID:15674280

  2. Sexuality and Islam.

    PubMed

    Dialmy, Abdessamad

    2010-06-01

    This paper deals with three major questions: (1) What are the sexual norms defined by the sacred texts (Koran and Sunna)? (2) What are the sexual practices currently observed among Moslems? (3) To which extent are current sexual practices of Moslems dissociated from Islamic sexual norms? Sexual standards in Islam are paradoxical: on the one hand, they allow and actually are an enticement to the exercise of sexuality but, on the other hand, they discriminate between male and female sexuality, between marital and pre- or extramarital sexuality, and between heterosexuality and homosexuality. Men are given more rights with regard to the expression of their sexuality; women are forbidden to have extramarital sex (with their slaves) and both genders to have homosexual relationships. The combination of these paradoxical standards with modernisation leads to the current back and forth swing of sexual practices between repression and openness. Partial modernisation leads to greater sexual tolerance. But restrictive sexual standards have gathered strength and have become idealised as a result of the current radicalisation of Islam. This swing of the pendulum between repression and openness is illustrated by phenomena such as public harassment, premarital sexuality, female pleasure, prostitution, and homosexuality. Currently, Islam is not any more the only reference which provides guidance concerning sexual practices but secularisation of sexual laws is still politically unthinkable today. So the only solution is to achieve reform in the name of Islam, through the reinterpretation of repressive holy texts. PMID:20441406

  3. Human vision fails to distinguish widespread sexual dichromatism among sexually "monochromatic" birds.

    PubMed

    Eaton, Muir D

    2005-08-01

    Historical scenarios of evolution of avian plumage coloration have been called into question with the discoveries that most birds can see UV light (which normal humans cannot), and that UV-reflecting plumages are widespread in birds. Several examples of sexual dichromatism not detectable with human visual capabilities suggest that our categorizations of plumages as sexually mono- or dichromatic might often be incorrect. Nonetheless, given the limited taxonomic scope of those examples, the vast majority of sexually monochromatic birds are still treated as such without question in avian research. Herein, I show that >90% of 139 species, in a broad sampling of presumed sexually monochromatic passerine birds, were actually sexually dichromatic from an avian visual perspective, based on comparisons of plumage reflectance data using a visual model of color discrimination thresholds. The taxonomic ubiquity of this result suggests that many existing interpretations of evolutionary patterns of sexual dichromatism in birds are erroneous. The visual model used herein provides a method for quantifying sexual dichromatism, revealing that most (58.7%) feather patches sampled lie along a continuum of dichromatism between avian and human discriminatory abilities and could represent unrecognized sexually selected signals. Sexual dichromatism in this study rarely resulted from intersexual differences in UV coloration alone, emphasizing the need for analysis of bird coloration in relation to the full extent of avian visual discriminatory abilities, including, but not limited to, UV-visual capabilities. PMID:16033870

  4. Endocrine regulation and sexual differentiation of avian copulatory sexually selected characters.

    PubMed

    Brennan, Patricia L R; Adkins-Regan, Elizabeth

    2014-10-01

    Reproductive specializations in birds have provided intriguing model systems to better understand the role of endocrine mechanisms that regulate phenotype expression and the action of sexual selection. A comparative approach can elucidate how endocrine systems associated with control of sexual differentiation, sexual maturation, and reproductive physiology and behavior have diversified. Here we compare the copulatory sexually selected traits of two members of the galloanseriform superfamily: quail and ducks. Japanese quail have a non-intromittent penis, and they have evolved a unique foam gland that is known to be involved in post-copulatory sexual selection. In contrast, ducks have maintained a large intromittent penis that has evolved via copulatory male-male competition and has been elaborated in a sexually antagonistic race due to sexual conflict with females over mating. These adaptations function in concert with sex-specific and, in part, species-specific behaviors. Although the approaches to study these traits have been different, exploring the differences in neuroendocrine regulation of sexual behavior, development and seasonality of the foam gland and the penis side by side, allow us to suggest some areas where future research would be productive to better understand the evolution of novelty in sexually selected traits. PMID:25179524

  5. KALMAN FILTERING REPRODUCING KERNEL HILBERT SPACES

    E-print Network

    Slatton, Clint

    KALMAN FILTERING IN REPRODUCING KERNEL HILBERT SPACES Pingping Zhu #12;Outline · Introduction · Related Work · A Novel Extended Kernel Recursive Least Squares · Kernel Kalman Filter based on Conditional · Develop a Kalman filter in the Reproducing kernel Hilbert space (RKHS) Motivation · Kernel methods can

  6. Is there evidence of sexual reproduction (meiosis) in Acanthamoeba?

    PubMed

    Khan, Naveed A; Siddiqui, Ruqaiyyah

    2015-06-01

    Evolution of independently breeding species into males and females (gametes) has remained a puzzle. Given the significant advantages of sexual reproduction over asexual reproduction as a long-term species survival strategy; here, we pose the question whether there is some form of meiosis in Acanthamoeba species, which represents our ancient lineage. The recently available Acanthamoeba genome revealed several genes implicated in meiosis in sexual eukaryotes such as Spo11, Mre11, Rad50, Rad51, Rad52, Mnd1, Dmc1, Msh, and Mlh, suggesting that Acanthamoeba is capable of some form of meiosis, inferring the presence of sexual reproduction in Acanthamoeba, and that meiosis evolved early in eukaryotic evolution. PMID:25800982

  7. Indian concepts on sexuality

    PubMed Central

    Chakraborty, Kaustav; Thakurata, Rajarshi Guha

    2013-01-01

    India is a vast country depicting wide social, cultural and sexual variations. Indian concept of sexuality has evolved over time and has been immensely influenced by various rulers and religions. Indian sexuality is manifested in our attire, behavior, recreation, literature, sculptures, scriptures, religion and sports. It has influenced the way we perceive our health, disease and device remedies for the same. In modern era, with rapid globalization the unique Indian sexuality is getting diffused. The time has come to rediscover ourselves in terms of sexuality to attain individual freedom and to reinvest our energy to social issues related to sexuality. PMID:23858263

  8. Causes of sexual dysfunction (image)

    MedlinePLUS

    Female sexual dysfunction describes women who are indifferent or hostile to sexual intercourse, who have no response to sexual advances or stimulation, or who are unable to have an orgasm during sexual intercourse.

  9. ORIGINAL PAPER Sexual Victimization, Alcohol Intoxication, Sexual-Emotional

    E-print Network

    combine to exacerbate their sexual risks. Keywords Child sexual abuse Á Sexual assault Á Alcohol Á Sexual in the past year, completed childhood sexual abuse (CSA) and adolescent/adult sexual assault(ASA) measures, Gender, and Reproduction, Indiana University, Bloomington, IN, USA J. Norris Alcohol and Drug Abuse

  10. Parasitism and the expression of sexual dimorphism

    PubMed Central

    De Lisle, Stephen P; Rowe, Locke

    2015-01-01

    Although a negative covariance between parasite load and sexually selected trait expression is a requirement of few sexual selection models, such a covariance may be a general result of life-history allocation trade-offs. If both allocation to sexually selected traits and to somatic maintenance (immunocompetence) are condition dependent, then in populations where individuals vary in condition, a positive covariance between trait expression and immunocompetence, and thus a negative covariance between trait and parasite load, is expected. We test the prediction that parasite load is generally related to the expression of sexual dimorphism across two breeding seasons in a wild salamander population and show that males have higher trematode parasite loads for their body size than females and that a key sexually selected trait covaries negatively with parasite load in males. We found evidence of a weaker negative relationship between the analogous female trait and parasite infection. These results underscore that parasite infection may covary with expression of sexually selected traits, both within and among species, regardless of the model of sexual selection, and also suggest that the evolution of condition dependence in males may affect the evolution of female trait expression. PMID:25750721

  11. Sexual Dimorphism

    E-print Network

    Frayer, David W.; Wolpoff, Milford H.

    1985-01-01

    /10/05. For personal use only. 436 FRAYER & WOLPOFF compare across different taxa. For example, both Leutenegger & Cheverud (198) and Gaulin & Sailer (107) include solitary species of prosimians in their analysis as nonmonogamous, yet this form of polygyny... is not comparable to the more social prosimians let alone higher primates. At the same time, there are different intensities of polygyny in Old World monkeys and apes which call into question correlations across major taxa. We have combined the data of Leutenegger...

  12. An Overview of Sexual Harassment

    ERIC Educational Resources Information Center

    Stier, William F., Jr.

    2005-01-01

    Sexual harassment, according to the Equal Employment Opportunity Commission (EEOC), is when any unwelcome sexual advances for sexual favors, and other verbal or physical conduct of a sexual nature takes place. For sexual harassment to take place there must be some type of behavior, language, or material of a sexual nature, which is offensive.…

  13. The Economics of Reproducibility in Preclinical Research

    PubMed Central

    Freedman, Leonard P.; Cockburn, Iain M.; Simcoe, Timothy S.

    2015-01-01

    Low reproducibility rates within life science research undermine cumulative knowledge production and contribute to both delays and costs of therapeutic drug development. An analysis of past studies indicates that the cumulative (total) prevalence of irreproducible preclinical research exceeds 50%, resulting in approximately US$28,000,000,000 (US$28B)/year spent on preclinical research that is not reproducible—in the United States alone. We outline a framework for solutions and a plan for long-term improvements in reproducibility rates that will help to accelerate the discovery of life-saving therapies and cures. PMID:26057340

  14. BARNARD COLLEGE SEXUAL VIOLENCE

    E-print Network

    nature. Unwelcome sexual advances, requests for sexual favors, and other verbal, nonverbal or physical of consent involves explicit communication and mutual approval for the act in which the parties are

  15. Teen Sexual Health

    MedlinePLUS

    ... sex puts you at risk of getting a sexually transmitted disease, such as herpes or genital warts, or HIV, ... however, latex condoms are the best protection against sexually transmitted diseases (STDs). Condoms are also a form of birth ...

  16. Sexual Problems in Women

    MedlinePLUS

    ... results from past sexual trauma. Occasional problems with sexual function are common. If problems last more than a few months or cause distress for you or your partner, you should see your health care provider.

  17. Sexuality in Older Adults

    MedlinePLUS

    ... feel good about yourself. As you age, your sexual health will change. But growing older doesn’t have ... life at any age. How does aging affect sexual health? Changes for women: As a woman approaches menopause, ...

  18. Children and Sexuality.

    ERIC Educational Resources Information Center

    Corbett, Susan Miller

    1991-01-01

    Presents a newsletter that discusses methods parents can use to handle sexual questions or behavior in young children. An accompanying letter to parents addresses young children's sexual behavior and ways parents can respond to this behavior. (GH)

  19. Sexual Assault against Females

    MedlinePLUS

    ... give her consent because she is under the influence of alcohol or drugs threatened to be hurt ... do sexual assaults happen? Estimating rates of sexual violence against women is a difficult task. Many factors ...

  20. Notes on sexuality & space

    E-print Network

    Jacobson, Samuel Ray

    2013-01-01

    Very little has been written on sexuality in architectural scholarship. Sexuality & Space (Princeton Architectural Press, 1992) contains the proceedings of an eponymous 1990 conference at Princeton University, and was both ...

  1. Sexual Orientation (For Parents)

    MedlinePLUS

    ... Development Infections Diseases & Conditions Pregnancy & Baby Nutrition & Fitness Emotions & Behavior School & Family Life First Aid & Safety Doctors & ... Pregnant? What to Expect Sexual Orientation KidsHealth > Parents > Emotions & Behavior > Feelings & Emotions > Sexual Orientation Print A A ...

  2. Sexual imprinting on ecologically divergent traits leads to sexual isolation in sticklebacks

    PubMed Central

    Kozak, Genevieve M.; Head, Megan L.; Boughman, Janette W.

    2011-01-01

    During sexual imprinting, offspring learn parental phenotypes and then select mates who are similar to their parents. Imprinting has been thought to contribute to the process of speciation in only a few rare cases; this is despite imprinting's potential to generate assortative mating and solve the problem of recombination in ecological speciation. If offspring imprint on parental traits under divergent selection, these traits will then be involved in both adaptation and mate preference. Such ‘magic traits’ easily generate sexual isolation and facilitate speciation. In this study, we show that imprinting occurs in two ecologically divergent stickleback species (benthics and limnetics: Gasterosteus spp.). Cross-fostered females preferred mates of their foster father's species. Furthermore, imprinting is essential for sexual isolation between species; isolation was reduced when females were raised without fathers. Daughters imprinted on father odour and colour during a critical period early in development. These traits have diverged between the species owing to differences in ecology. Therefore, we provide the first evidence that imprinting links ecological adaptation to sexual isolation between species. Our results suggest that imprinting may facilitate the evolution of sexual isolation during ecological speciation, may be especially important in cases of rapid diversification, and thus play an integral role in the generation of biodiversity. PMID:21270044

  3. Significance of temporal and spectral acoustic cues for sexual recognition in Xenopus laevis

    E-print Network

    Kelley, Darcy B.

    recognition and for spectral acoustic cues in conveying female attractiveness in X. laevis. Keywords: inter-sexualSignificance of temporal and spectral acoustic cues for sexual recognition in Xenopus laevis Cle As in many anurans, males of the totally aquatic species, Xenopus laevis, advertise their sexual receptivity

  4. Symbiotic Combination as an Alternative to Sexual Recombination in Genetic Algorithms

    E-print Network

    Pollack, Jordan B.

    reproduction. Sexual recombination occurs between similar organisms (i.e. of the same species) and involvesSymbiotic Combination as an Alternative to Sexual Recombination in Genetic Algorithms Richard A is more closely analogous to combination of symbiotic organisms than it is to sexual recombination

  5. Sexual reproduction prevails in a world of structured resources in short supply

    PubMed Central

    Scheu, S; Drossel, B

    2007-01-01

    We present a model for the maintenance of sexual reproduction based on the availability of resources, which is the strongest factor determining the growth of populations. The model compares completely asexual species to species that switch between asexual and sexual reproduction (sexual species). Key features of the model are that sexual reproduction sets in when resources become scarce, and that at a given place only a few genotypes can be present at the same time. We show that under a wide range of conditions the sexual species outcompete the asexual ones. The asexual species win only when survival conditions are harsh and death rates are high, or when resources are so little structured or consumer genotypes are so manifold that all resources are exploited to the same extent. These conditions, largely represent the conditions in which sexuals predominate over asexuals in the field. PMID:17327204

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

    E-print Network

    Berdichevsky, Victor

    on college campuses. ! FBI statistics indicate that 1 out of 4 women and 1 out of 10 men will be a survivor, guilt) $ Date rape, a form of sexual assault, is rape by someone the victim is dating. $ Acquaintance rape, a form of sexual assault, is rape by a non-stranger, such as a friend #12;Defining the Terms

  7. Reproducible research in vadose zone sciences

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A significant portion of present-day soil and Earth science research is computational, involving complex data analysis pipelines, advanced mathematical and statistical models, and sophisticated computer codes. Opportunities for scientific progress are greatly diminished if reproducing and building o...

  8. Reproducibility of MRE shear modulus estimates

    NASA Astrophysics Data System (ADS)

    Weaver, John B.; Miller, Timothy B.; Doyley, Marvin D.; Wang, Huifang; Perrinez, Phillip R.; Cheung, Yvonne Y.; Kennedy, Francis E.; Paulsen, Keith D.

    2007-03-01

    A significant effort has been expended to measure the accuracy of the shear modulus estimates. Conversely, very little effort has been expended to establish the reproducibility of the method in a clinical context. Previously we established the reproducibility in phantoms to be 3% for repeated measurements without moving the phantom and 5% when the phantom was moved,however, the clinical reproducibility has not been demonstrated. The reproducibility of the method was estimated by scanning subjects' heels repeatedly on a GE 1.5T scanner using previously described methods. Three subjects were scanned three times on different days (termed non-consecutive) and three subjects were scanned three times in the same session without changing the position of the foot (termed consecutive). The average difference between mean values within the field of view for the non-consecutive group was 7.75% +/- 3.76% and for the consecutive group it was 5.30% +/- 4.16%. These values represent remarkably good reproducibility considering the 20% variation in shear modulus observed within individual heels and the several hundred percent changes observed between normal and pathologic tissues. The variation in repeated examinations was caused by four factors: positioning error between examinations accounted for 4.8%, computational noise 3.0%, and the combination of MR noise and patient motion during the examination, 5.3%. Each of these sources of variation can be reduced in relatively straightforward ways if necessary but the current level of reproducibility is sufficient for most current applications.

  9. Sexual Intimacy After Sexual Assault or Sexual Abuse1

    E-print Network

    Machel, Hans

    are not permanent, they can be very frustrating as they can decrease the enjoyment of one's sexual life and intimacy fearing losing control of their body or feeling vulnerable to someone else. Others may react by having

  10. Necrophilia and sexual homicide.

    PubMed

    Stein, Michelle L; Schlesinger, Louis B; Pinizzotto, Anthony J

    2010-03-01

    A closed case-file review of 211 sexual homicides identified 16 cases of necrophilia. The results of this unique descriptive study of necrophilia associated with sexual homicide provide information on crime-scene locations, methods of killing, body disposition, premortem sexual assault, specifics of the necrophilic acts, methods of victim abduction, and motivational dynamics. The findings suggest that the most common explanation for necrophilia-the offender's desire to have an unresisting partner-may not always be applicable in cases where this rare paraphilia is connected to sexual murder. The possibility of using crime-scene behaviors in these cases to investigate serial sexual murders is offered. PMID:20102474

  11. Data quality in predictive toxicology: reproducibility of rodent carcinogenicity experiments.

    PubMed Central

    Gottmann, E; Kramer, S; Pfahringer, B; Helma, C

    2001-01-01

    We compared 121 replicate rodent carcinogenicity assays from the two parts (National Cancer Institute/National Toxicology Program and literature) of the Carcinogenic Potency Database (CPDB) to estimate the reliability of these experiments. We estimated a concordance of 57% between the overall rodent carcinogenicity classifications from both sources. This value did not improve substantially when additional biologic information (species, sex, strain, target organs) was considered. These results indicate that rodent carcinogenicity assays are much less reproducible than previously expected, an effect that should be considered in the development of structure-activity relationship models and the risk assessment process. PMID:11401763

  12. Maintaining sexuality in menopause.

    PubMed

    Nappi, Rossella E; Martini, Ellis; Martella, Silvia; Capuano, Francesca; Bosoni, David; Giacomini, Sonia; Beraghi, Matteo; Spinillo, Arsenio

    2014-03-13

    Sexual health in the menopause is a medical challenge because the progressive decline of sexual hormones interacts with the aging process and many psychosocial stressors modulate vulnerability for sexual symptoms (low sexual desire, poor arousal and lubrication, dyspareunia, orgasmic dysfunction and lack of satisfaction). In clinical practice, a coordinated approach is needed to optimally manage the risk for developing female sexual dysfunction (FSD), especially when chronic conditions are present. Biomedical and psychosocial interventions include general education, recognition of signs and symptoms, promotion of health, attention to the partner and individualization of treatment. Counselling to overcome personal and relational difficulties should be always combined with hormonal and non-hormonal strategies to maximize biological signals driving the sexual response. By enhancing women's abilities to cope with sexual changes at midlife, health care providers may significantly optimize healthy aging and partnership. PMID:24879777

  13. Assessing the reproducibility of discriminant function analyses

    PubMed Central

    Andrew, Rose L.; Albert, Arianne Y.K.; Renaut, Sebastien; Rennison, Diana J.; Bock, Dan G.

    2015-01-01

    Data are the foundation of empirical research, yet all too often the datasets underlying published papers are unavailable, incorrect, or poorly curated. This is a serious issue, because future researchers are then unable to validate published results or reuse data to explore new ideas and hypotheses. Even if data files are securely stored and accessible, they must also be accompanied by accurate labels and identifiers. To assess how often problems with metadata or data curation affect the reproducibility of published results, we attempted to reproduce Discriminant Function Analyses (DFAs) from the field of organismal biology. DFA is a commonly used statistical analysis that has changed little since its inception almost eight decades ago, and therefore provides an opportunity to test reproducibility among datasets of varying ages. Out of 100 papers we initially surveyed, fourteen were excluded because they did not present the common types of quantitative result from their DFA or gave insufficient details of their DFA. Of the remaining 86 datasets, there were 15 cases for which we were unable to confidently relate the dataset we received to the one used in the published analysis. The reasons ranged from incomprehensible or absent variable labels, the DFA being performed on an unspecified subset of the data, or the dataset we received being incomplete. We focused on reproducing three common summary statistics from DFAs: the percent variance explained, the percentage correctly assigned and the largest discriminant function coefficient. The reproducibility of the first two was fairly high (20 of 26, and 44 of 60 datasets, respectively), whereas our success rate with the discriminant function coefficients was lower (15 of 26 datasets). When considering all three summary statistics, we were able to completely reproduce 46 (65%) of 71 datasets. While our results show that a majority of studies are reproducible, they highlight the fact that many studies still are not the carefully curated research that the scientific community and public expects. PMID:26290793

  14. Sexually Selected Infanticide in a Polygynous Bat

    PubMed Central

    Knörnschild, Mirjam; Ueberschaer, Katja; Helbig, Maria; Kalko, Elisabeth K. V.

    2011-01-01

    Background Adult individuals of many species kill unrelated conspecific infants for several adaptive reasons ranging from predation or resource competition to the prevention of misdirected parental care. Moreover, infanticide can increase the reproductive success of the aggressor by killing the offspring of competitors and thereafter mating with the victimized females. This sexually selected infanticide predominantly occurs in polygynous species, with convincing evidence for primates, carnivores, equids, and rodents. Evidence for bats was predicted but lacking. Methodology/Principal Findings Here we report the first case, to our knowledge, of sexually selected infanticide in a bat, the polygynous white-throated round-eared bat, Lophostoma silvicolum. Behavioral studies in a free-living population revealed that an adult male repeatedly attacked and injured the pups of two females belonging to his harem, ultimately causing the death of one pup. The infanticidal male subsequently mated with the mother of the victimized pup and this copulation occurred earlier than any other in his harem. Conclusions/Significance Our findings indicate that sexually selected infanticide is more widespread than previously thought, adding bats as a new taxon performing this strategy. Future work on other bats, especially polygynous species in the tropics, has great potential to investigate the selective pressures influencing the evolution of sexually selected infanticide and to study how infanticide impacts reproductive strategies and social structures of different species. PMID:21949829

  15. Intrauterine Position Effects on Sexually Dimorphic Asymmetries

    E-print Network

    Galef Jr., Bennett G.

    Intrauterine Position Effects on Sexually Dimorphic Asymmetries of Mongolian Gerbils: Testosterone gerbils. We found that (I) the order in which the eyes of individual gerbil pups opened varied right eyes, and (2) the paw that adult gerbils held in the air while maintaining a species

  16. Sexual Assault and Sexually Transmitted Infections in Adults, Adolescents, and Children.

    PubMed

    Seńa, Arlene C; Hsu, Katherine K; Kellogg, Nancy; Girardet, Rebecca; Christian, Cindy W; Linden, Judith; Griffith, William; Marchant, Anne; Jenny, Carole; Hammerschlag, Margaret R

    2015-12-15

    Survivors of sexual assault are at risk for acquiring sexually transmitted infections (STIs). We conducted literature reviews and invited experts to assist in updating the sexual assault section for the 2015 Centers for Disease Control and Prevention sexually transmitted diseases (STD) treatment guidelines. New recommendations for STI management among adult and adolescent sexual assault survivors include use of nucleic acid amplification tests (NAATs) for detection of Trichomonas vaginalis by vaginal swabs; NAATs for detection of Neisseria gonorrhoeae and Chlamydia trachomatis from pharyngeal and rectal specimens among patients with a history of exposure or suspected extragenital contact after sexual assault; empiric therapy for gonorrhea, chlamydia, and trichomoniasis based on updated treatment regimens; vaccinations for human papillomavirus (HPV) among previously unvaccinated patients aged 9-26 years; and consideration for human immunodeficiency virus (HIV) nonoccupational postexposure prophylaxis using an algorithm to assess the timing and characteristics of the exposure. For child sexual assault (CSA) survivors, recommendations include targeted diagnostic testing with increased use of NAATs when appropriate; routine follow-up visits within 6 months after the last known sexual abuse; and use of HPV vaccination in accordance with national immunization guidelines as a preventive measure in the post-sexual assault care setting. For CSA patients, NAATs are considered to be acceptable for identification of gonococcal and chlamydial infections from urine samples, but are not recommended for extragenital testing due to the potential detection of nongonococcal Neisseria species. Several research questions were identified regarding the prevalence, detection, and management of STI/HIV infections among adult, adolescent, and pediatric sexual assault survivors. PMID:26602623

  17. Reproducibility responsibilities in the HPC arena

    SciTech Connect

    Fahey, Mark R; McLay, Robert

    2014-01-01

    Expecting bit-for-bit reproducibility in the HPC arena is not feasible because of the ever changing hardware and software. No user s application is an island; it lives in an HPC eco-system that changes over time. Old hardware stops working and even old software won t run on new hardware. Further, software libraries change over time either by changing the internals or even interfaces. So bit-for-bit reproducibility should not be expected. Rather a reasonable expectation is that results are reproducible within error bounds; or that the answers are close (which is its own debate.) To expect a researcher to reproduce their own results or the results of others within some error bounds, there must be enough information to recreate all the details of the experiment. This requires complete documentation of all phases of the researcher s workflow; from code to versioning to programming and runtime environments to publishing of data. This argument is the core statement of the Yale 2009 Declaration on Reproducible Research [1]. Although the HPC ecosystem is often outside the researchers control, the application code could be built almost identically and there is a chance for very similar results with just only round-off error differences. To achieve complete documentation at every step, the researcher, the computing center, and the funding agencies all have a role. In this thesis, the role of the researcher is expanded upon as compared to the Yale report and the role of the computing centers is described.

  18. Relevance relations for the concept of reproducibility

    PubMed Central

    Atmanspacher, H.; Bezzola Lambert, L.; Folkers, G.; Schubiger, P. A.

    2014-01-01

    The concept of reproducibility is widely considered a cornerstone of scientific methodology. However, recent problems with the reproducibility of empirical results in large-scale systems and in biomedical research have cast doubts on its universal and rigid applicability beyond the so-called basic sciences. Reproducibility is a particularly difficult issue in interdisciplinary work where the results to be reproduced typically refer to different levels of description of the system considered. In such cases, it is mandatory to distinguish between more and less relevant features, attributes or observables of the system, depending on the level at which they are described. For this reason, we propose a scheme for a general ‘relation of relevance’ between the level of complexity at which a system is considered and the granularity of its description. This relation implies relevance criteria for particular selected aspects of a system and its description, which can be operationally implemented by an interlevel relation called ‘contextual emergence’. It yields a formally sound and empirically applicable procedure to translate between descriptive levels and thus construct level-specific criteria for reproducibility in an overall consistent fashion. Relevance relations merged with contextual emergence challenge the old idea of one fundamental ontology from which everything else derives. At the same time, our proposal is specific enough to resist the backlash into a relativist patchwork of unconnected model fragments. PMID:24554574

  19. Reproducible network benchmarks with coNCEPTUAL

    SciTech Connect

    Pakin, S. D.

    2004-01-01

    A cornerstone of scientific progress is the ability to reproduce experimental results. However, in the context of network benchmarking, system complexity impedes a researcher's attempts to record all of the information needed to exactly reconstruct a network-benchmarking experiment. Without this information, results may be misinterpreted and are unlikely to be reproducible. This paper presents a tool called CONCEPTUAL which simplifies most aspects of recording and presenting network performance data. CONCEPTUAL includes two core components: (1) a compiler for a high-level, domain-specific programming language that makes it possible to specify arbitrary communication patterns tersely but precisely and (2) a complementary run-time library that obviates the need for writing (and debugging) all of the mundane but necessary routines needed for benchmarking, such as those that calibrate timers, compute statistics, or output log files. The result is that CONCEPTUAL makes it easy to present network-performance data in a form that promotes reproducibility.

  20. Disruption of adult expression of sexually selected traits by developmental exposure to bisphenol A

    PubMed Central

    Jašarevi?, Eldin; Sieli, Paizlee T.; Twellman, Erin E.; Welsh, Thomas H.; Schachtman, Todd R.; Roberts, R. Michael; Geary, David C.; Rosenfeld, Cheryl S.

    2011-01-01

    Exposure to endocrine disrupting compounds (EDCs), such as bisphenol A (BPA), may cause adverse health effects in wildlife and humans, but controversy remains as to what traits are most sensitive to EDCs and might serve as barometers of exposure. Expression of sexually selected traits that have evolved through intrasexual competition for mates and intersexual choice of mating partner are more dependent on developmental and physical condition of an animal than naturally selected traits and thus might be particularly vulnerable to disruption by developmental exposure to EDCs. We have used the deer mouse (Peromyscus maniculatus) as a model to test this hypothesis. Adult male–male competition for mates in this species is supported by enhanced spatial navigational and exploratory abilities, which enable males to search for prospective, widely dispersed females. Male deer mice exposed to BPA or ethinyl estradiol (EE) through maternal diet showed no changes in external phenotype, sensory development, or adult circulating concentrations of testosterone and corticosterone, but spatial learning abilities and exploratory behaviors were severely compromised compared with control males. Because these traits are not sexually selected in females, BPA exposure predictably had no effect, although EE-exposed females demonstrated enhanced spatial navigational abilities. Both BPA-exposed and control females preferred control males to BPA-exposed males. Our demonstration that developmental exposure to BPA compromises cognitive abilities and behaviors essential for males to reproduce successfully has broad implications for other species, including our own. Thus, sexually selected traits might provide useful biomarkers to assess risk of environmental contamination in animal and human populations. PMID:21709224

  1. Disruption of adult expression of sexually selected traits by developmental exposure to bisphenol A.

    PubMed

    Jašarevi?, Eldin; Sieli, Paizlee T; Twellman, Erin E; Welsh, Thomas H; Schachtman, Todd R; Roberts, R Michael; Geary, David C; Rosenfeld, Cheryl S

    2011-07-12

    Exposure to endocrine disrupting compounds (EDCs), such as bisphenol A (BPA), may cause adverse health effects in wildlife and humans, but controversy remains as to what traits are most sensitive to EDCs and might serve as barometers of exposure. Expression of sexually selected traits that have evolved through intrasexual competition for mates and intersexual choice of mating partner are more dependent on developmental and physical condition of an animal than naturally selected traits and thus might be particularly vulnerable to disruption by developmental exposure to EDCs. We have used the deer mouse (Peromyscus maniculatus) as a model to test this hypothesis. Adult male-male competition for mates in this species is supported by enhanced spatial navigational and exploratory abilities, which enable males to search for prospective, widely dispersed females. Male deer mice exposed to BPA or ethinyl estradiol (EE) through maternal diet showed no changes in external phenotype, sensory development, or adult circulating concentrations of testosterone and corticosterone, but spatial learning abilities and exploratory behaviors were severely compromised compared with control males. Because these traits are not sexually selected in females, BPA exposure predictably had no effect, although EE-exposed females demonstrated enhanced spatial navigational abilities. Both BPA-exposed and control females preferred control males to BPA-exposed males. Our demonstration that developmental exposure to BPA compromises cognitive abilities and behaviors essential for males to reproduce successfully has broad implications for other species, including our own. Thus, sexually selected traits might provide useful biomarkers to assess risk of environmental contamination in animal and human populations. PMID:21709224

  2. Youth Who Sexual Offended

    PubMed Central

    Koh, Li Lian; Zeng, Gerald; Teoh, Jennifer

    2015-01-01

    There has been an increased focus on understanding youth sexual offending in recent years, but there has been limited empirical research on the causes, pathways, and treatment of youth who have sexually offended—especially within a non-Western context. The Good Lives and Self-Regulation Models have often been used to understand and rehabilitate adult sexual offenders, but (unfortunately) there is scant research on youth who sexually offended using these models. The present study aims to describe the different primary goods that are associated with youth sexual offending behaviors in an Asian context. In addition, the study sought to explore whether the age of victim (child vs. nonchild) and nature of sexual offense (penetrative vs. nonpenetrative) influenced the youth’s engagement in offense pathways. The results suggest that pleasure, relatedness, and inner peace were the primary human goods that were most sought after by a sample of 168 youth who sexually offended in Singapore. In addition, offender classification (in relation to the age of victim and nature of sexual offense) influenced the pathways to sexual offending. Therefore, these findings have important clinical implications for assessment, management, and intervention planning for youth who sexually offended. PMID:24048701

  3. Orchid pollination by sexual deception: pollinator perspectives.

    PubMed

    Gaskett, A C

    2011-02-01

    The extraordinary taxonomic and morphological diversity of orchids is accompanied by a remarkable range of pollinators and pollination systems. Sexually deceptive orchids are adapted to attract specific male insects that are fooled into attempting to mate with orchid flowers and inadvertently acting as pollinators. This review summarises current knowledge, explores new hypotheses in the literature, and introduces some new approaches to understanding sexual deception from the perspective of the duped pollinator. Four main topics are addressed: (1) global patterns in sexual deception, (2) pollinator identities, mating systems and behaviours, (3) pollinator perception of orchid deceptive signals, and (4) the evolutionary implications of pollinator responses to orchid deception, including potential costs imposed on pollinators by orchids. A global list of known and putative sexually deceptive orchids and their pollinators is provided and methods for incorporating pollinator perspectives into sexual deception research are provided and reviewed. At present, almost all known sexually deceptive orchid taxa are from Australia or Europe. A few sexually deceptive species and genera are reported for New Zealand and South Africa. In Central and Southern America, Asia, and the Pacific many more species are likely to be identified in the future. Despite the great diversity of sexually deceptive orchid genera in Australia, pollination rates reported in the literature are similar between Australian and European species. The typical pollinator of a sexually deceptive orchid is a male insect of a species that is polygynous, monandrous, haplodiploid, and solitary rather than social. Insect behaviours involved in the pollination of sexually deceptive orchids include pre-copulatory gripping of flowers, brief entrapment, mating, and very rarely, ejaculation. Pollinator behaviour varies within and among pollinator species. Deception involving orchid mimicry of insect scent signals is becoming well understood for some species, but visual and tactile signals such as colour, shape, and texture remain neglected. Experimental manipulations that test for function, multi-signal interactions, and pollinator perception of these signals are required. Furthermore, other forms of deception such as exploitation of pollinator sensory biases or mating preferences merit more comprehensive investigation. Application of molecular techniques adapted from model plants and animals is likely to deliver new insights into orchid signalling, and pollinator perception and behaviour. There is little current evidence that sexual deception drives any species-level selection on pollinators. Pollinators do learn to avoid deceptive orchids and their locations, but this is not necessarily a response specific to orchids. Even in systems where evidence suggests that orchids do interfere with pollinator mating opportunities, considerable further research is required to determine whether this is sufficient to impose selection on pollinators or generate antagonistic coevolution or an arms race between orchids and their pollinators. Botanists, taxonomists and chemical ecologists have made remarkable progress in the study of deceptive orchid pollination. Further complementary investigations from entomology and behavioural ecology perspectives should prove fascinating and engender a more complete understanding of the evolution and maintenance of such enigmatic plant-animal interactions. PMID:20377574

  4. Somnambulistic sexual behaviour (sexsomnia).

    PubMed

    Ebrahim, Irshaad Osman

    2006-05-01

    Somnambulism or sleepwalking is a viable defence on the basis of automatism. The behaviours that occur during sleepwalking can be highly complex and include sexual behaviour of all types. Somnambulistic sexual behaviour (also called sexsomnia, sleep sex) is considered a variant of sleepwalking disorder as the overwhelming majority of people with Sexsomnia have a history of parasomnia and a family history of sleepwalking. Sexual behaviour during a sleep automatism can vary from explicit sexual vocalisations, to violent masturbation, to complex sexual acts including anal, oral and vaginal penetration. A recent case in England is reported where the defendant was acquitted on 3 charges of rape on the basis of automatism due to somnambulistic sexual behaviour. PMID:16564199

  5. Sexuality and headache.

    PubMed

    Del Bene, E; Conti, C; Poggioni, M; Sicuteri, F

    1982-01-01

    Ten percent of 362 headache sufferers reported sexual arousal during migraine attack. Clinical investigations on sexuality in 16 headache sufferers, according to some studies showing correlations between idiopathic headache and sexual behavior, were performed. Patients responding by questionnaire listed each sexual experience, headache attack, and number of sleeping hours every day for 1 month. In both men and women, the number of coiti, erotic dreams, and sleeping hours were similar in headache sufferers and controls, while the frequency of masturbation was significantly reduced in the former. Sexual excitement and fantasies appeared more often in female headache sufferers than in controls, while the opposite occurred in the male group. Among the clinical analogies between the crises of migraine and morphine abstinence, sexual arousal may be included. PMID:7054999

  6. Human Computation Must Be Reproducible Praveen Paritosh

    E-print Network

    Cortes, Corinna

    Human Computation Must Be Reproducible Praveen Paritosh Google 345 Spear St, San Francisco, CA 94105. pkp@google.com ABSTRACT Human computation is the technique of performing a com- putational process by outsourcing some of the difficult-to- automate steps to humans. In the social and behavioral

  7. Teacher's Role and Reproducibility of Didactical Situations.

    ERIC Educational Resources Information Center

    Arsac, Gilbert; And Others

    1992-01-01

    Teacher's abilities to remain sufficiently faithful to predefined learning scenarios are examined via case studies. The behavior of 2 teachers during problem-solving sessions in geometry with 13-14 year olds exhibited 2 types of factors that tend to hamper scenario reproducibility: constraints on the teacher resulting from the teaching situation;…

  8. Natural Disasters: Earth Science Readings. Reproducibles.

    ERIC Educational Resources Information Center

    Lobb, Nancy

    Natural Disasters is a reproducible teacher book that explains what scientists believe to be the causes of a variety of natural disasters and suggests steps that teachers and students can take to be better prepared in the event of a natural disaster. It contains both student and teacher sections. Teacher sections include vocabulary, an answer key,…

  9. Reproducibility, Controllability, and Optimization of Lenr Experiments

    NASA Astrophysics Data System (ADS)

    Nagel, David J.

    2006-02-01

    Low-energy nuclear reaction (LENR) measurements are significantly and increasingly reproducible. Practical control of the production of energy or materials by LENR has yet to be demonstrated. Minimization of costly inputs and maximization of desired outputs of LENR remain for future developments.

  10. Evolution and human sexuality.

    PubMed

    Gray, Peter B

    2013-12-01

    The aim of this review is to put core features of human sexuality in an evolutionary light. Toward that end, I address five topics concerning the evolution of human sexuality. First, I address theoretical foundations, including recent critiques and developments. While much traces back to Darwin and his view of sexual selection, more recent work helps refine the theoretical bases to sex differences and life history allocations to mating effort. Second, I consider central models attempting to specify the phylogenetic details regarding how hominin sexuality might have changed, with most of those models honing in on transitions from a possible chimpanzee-like ancestor to the slightly polygynous and long-term bonded sociosexual partnerships observed among most recently studied hunter-gatherers. Third, I address recent genetic and physiological data contributing to a refined understanding of human sexuality. As examples, the availability of rapidly increasing genomic information aids comparative approaches to discern signals of selection in sexuality-related phenotypes, and neuroendocrine studies of human responses to sexual stimuli provide insight into homologous and derived mechanisms. Fourth, I consider some of the most recent, large, and rigorous studies of human sexuality. These provide insights into sexual behavior across other national samples and on the Internet. Fifth, I discuss the relevance of a life course perspective to understanding the evolution of human sexuality. Most research on the evolution of human sexuality focuses on young adults. Yet humans are sexual beings from gestation to death, albeit in different ways across the life course, and in ways that can be theoretically couched within life history theory. PMID:24151100

  11. Female sexual dysfunction.

    PubMed

    Wright, Jennifer J; O'Connor, Kim M

    2015-05-01

    Female sexual dysfunction is a common patient concern. After providing an overview regarding the various types of female sexual dysfunction, we will focus on history taking and treatment options for desire, arousal, orgasm, and pain disorders. Testosterone therapy and management of selective serotonin reuptake inhibitor-associated sexual dysfunction are reviewed. Treatments for atrophic vaginitis are appraised. Patient cases lead the discussion, providing the reader with clinically relevant information. PMID:25841603

  12. Sexual morality of Christianity.

    PubMed

    Runkel, G

    1998-01-01

    After discussing the origin of religion, functions of religion, and the construction of meaning by religion, the author focuses on the connection between religion and anxiety. The permanent anxiety in religion is determined by guilt feelings that arise for example from the violation of norms in the area of sexuality. In a religion at enmity with sexuality, such as Christianity, the satisfaction of sexual desires is considered bad and sinful; the permanent production of anxiety and a guilty conscience are the result of it. Christian sexual suppression leads to the propagation of asceticism as the taming of corrupt sensuality that only religious virtuosi can maintain. One result of asceticism is celibacy, although passages from the Bible demand monogamy for bishops without prohibiting celibacy. In Catholicism, celibacy institutionalizes the enmity with sexuality and causes a permanent depreciation of real sexuality in favor of one projected onto the mother church and the Virgin Mary. A further consequence of asceticism is the reduction of sexuality to reproduction. In the section about the factual consequences of Christian sexual morality, the author connects sexual instinctual gratification with religious affiliation on the basis of an analysis of the sexual behavior of Germans. The weekly frequency rate of sexual intercourse amounts to 3.1 with male and female nondenominationals, 2.6 with Protestants, and 2.3 with Catholics; 39% of nondenominational men, 20% of Protestant men, and 12% of Catholic men in Germany use condoms. The connection of religion and aggression is empirically significant as well. The religiously most active men feel more inclined to use aggression to reach sexual goals than religiously indifferent ones. PMID:9611690

  13. Sexual health and contraception.

    PubMed

    Straw, Fiona; Porter, Charlotte

    2012-10-01

    Sexual health encompasses 'sexual development and reproductive health, as well as the ability to develop and maintain meaningful interpersonal relationships; appreciate one's own body; interact with both genders in respectful and appropriate ways; express affection, love and intimacy in ways consistent with one's own values'. The 2008 WHO Consensus Statement additionally noted that 'responsible adolescent intimate relationships' should be 'consensual, non-exploitative, honest, pleasurable and protected against unintended pregnancy and STDs if any type of intercourse occurs'. Young people (YP) must, therefore, be able to access sexual health information and services that meet their needs. For most YP, interest in sexual activity begins with puberty, and this is associated with increasingly sexualised behaviour, including exploration of themselves and others. Most YP find this a confusing time, and so it is important that health professionals are able to offer advice regarding the wide range of sexual health issues, including sexuality, choice of partner, contraception, risk and management of sexually transmitted infections (STI) in a confident and approachable manner. YP have never had so much choice or information available to them, and this can be confusing for them. There is good evidence that YP who get information from their parents are likely to initiate sexual activity later than their peers who access information from their friends. However, there is also evidence that some YP would prefer to get sexual health information from health professionals. It is therefore imperative that all health professionals who see YP have an awareness of sexual health issues, and know where to signpost YP should they need more specialist sexual health advice and/or treatment. Where appropriate, one-to-one sexual health advice should be provided to YP on how to prevent and get tested for STIs, and how to prevent unwanted pregnancies. Advice should also be given on all methods of reversible contraception, including long-acting reversible contraception, emergency contraception and other reproductive issues. PMID:22983512

  14. Sexual behavior in penguins.

    E-print Network

    Richdale, L. E. (Lancelot Eric)

    1951-01-01

    stream_size 667078 stream_content_type text/plain stream_name upk.sexual_behavior_in_penguins.pdf.txt stream_source_info upk.sexual_behavior_in_penguins.pdf.txt Content-Encoding UTF-8 Content-Type text/plain; charset=UTF-8... Sexual Behavior in Penguins Sexual Beh avior m Penguins hy L. E. Richdale, MA., H.D.A. Corresponding Fellow of the American Ornithologists' Union; Honorary Lecturer in Zoology, University of Otago, New Zealand University of Kansas Press...

  15. Sexually transmitted proctitis.

    PubMed

    Sigle, Gavin W; Kim, Rebekah

    2015-06-01

    There are many different sexually transmitted infections that can cause proctitis. Recognition of the common symptoms with anoscopic examination is crucial in accurate diagnosis of the pathogen. Clinicians should have a high index of suspicion of more than one inciting pathogen. Treatment should be prompt and extended to sexual partners who have been exposed to the disease. Effective treatment can alleviate the discomfort and potentially serious complications associated with sexually transmitted proctitides. This article illustrates and discusses the clinical presentations, diagnostic pearls, and treatments of sexually transmitted proctitides. PMID:26034402

  16. Michigan Technological University Sexual Assault,

    E-print Network

    means... Sexual Assault Sexual assault is an offense that meets one of these definitions below... Rape other within the degrees wherein marriage is prohibited by law. Statutory Rape. Sexual intercourse

  17. Radiation preservation study on middle host eggs of trichogramma species

    NASA Astrophysics Data System (ADS)

    Lianzhong, Ding; Zhengdong, Wu; Ping, Jiang; Zulin, Chen; Jianxin, Fu; Jianging, Shi

    1993-10-01

    Technical feasibility on the preservation of Antheraea pernyi's eggs, which are used as the middle hosts of Trichogramma dendrolimi Matsumura, irradiated by electron beam is studied in this paper. The results reveal that the preservative time of Antheraea pernyi's eggs irradiated by electron beam, combining with storage in a refrigerator, is notably prolonged in contrast with the control. When the irradiated eggs stored in a refrigerator for 89 days are serviced as hosts, the parasitic percentage for Trichogramma dendrolimi Matsumura is about 80 %. Besides, the emergence percentage, average numbers of parasitoids reproduced out of one egg, as well as body size, growing stage periods, and sexual rate of descendant are all normal. Irradiated eggs have not any adverse effects on the abilities of Trichogramma species and their offspring in both bearing and controlling insect pests.

  18. Evolution of sexuality: biology and behavior

    PubMed Central

    2005-01-01

    Sexual reproduction in animals and plants is far more prevalent than asexual reproduction, and there is no dearth of hypotheses attempting to explain why. Even bacteria and viruses, which reproduce by cloning, engage in promiscuous horizontal gene exchange (“parasexual reproduction”) on such short time scales that they evolve genotypic diversity even more rapidly than eukaryotes. (We confront this daily in the form of antimicrobial resistance.) The host-parasite and host-pathogen arms race purports to explain the prevalence of sexual reproduction, yet there are over a dozen other hypotheses, including the proposition that sexual reproduction purges the genome of deleterious mutations. An equally daunting challenge is to understand, in terms of evolutionary logic, the jungle of diverse courtship and mating strategies that we find in nature. The phenotypic plasticity of sex determination in animals suggests that the central nervous system and reproductive tract may not reach the same endpoint on the continuum between our stereotypic male and female extremes. Why are there only two kinds of gametes in most eukaryotes? Why are most flowering plants, and few animals, hermaphroditic? Why do male animals compete more for access to females than the other way around in most animals that have been studied?This review presents more questions than answers, but an extraordinary wealth of data has been collected, and new genetic techniques will provide new answers. The possible relevance of these data to human sexuality will be discussed in a future article. PMID:16200180

  19. [Psychoanalytic therapy of sexually abused adolescents].

    PubMed

    Hirsch, M

    1997-12-01

    Sexual abuse as an extreme childhood trauma produces distorted object-images, introjects of violence which reproduce the trauma permanently through symptoms and acting-out. Although the traumatic power should be relived in transference, psychoanalytic therapy does not always mean permanent interpretation of transference, rather supporting, confirming, valuing activity is indicated. The following scopes can be differentiated: idealization, changing the therapeutic object into a triangulating one; negative transference of an archaic destructive mother imago, nevertheless also of the traumatic object, setting free hidden aggressive affects; emerging of the specific sexual trauma in transference and counter-transference. In the whole course of therapy, especially at the end, working through of guilt-feelings, shame and mourning permits the separation from the traumatic objects, although the danger of returning to them, often represented by the real actual objects, does not guarantee a full success in all cases. PMID:9499697

  20. Dangerous Omissions: Abstinence-Only-until-Marriage School-Based Sexuality Education and the Betrayal of LGBTQ Youth

    ERIC Educational Resources Information Center

    Elia, John P.; Eliason, Mickey J.

    2010-01-01

    To gain an understanding of how abstinence-only-until-marriage school-based sexuality education has been exclusionary, it is important to explore how heteronormativity has been endorsed, played out, and reproduced ever since school-based sexuality education has been offered in the United States. Such an exploration reveals glaring evidence that…

  1. A Physical Activity Questionnaire: Reproducibility and Validity

    PubMed Central

    Barbosa, Nicolas; Sanchez, Carlos E.; Vera, Jose A.; Perez, Wilson; Thalabard, Jean-Christophe; Rieu, Michel

    2007-01-01

    This study evaluates the Quantification de L’Activite Physique en Altitude chez les Enfants (QAPACE) supervised self-administered questionnaire reproducibility and validity on the estimation of the mean daily energy expenditure (DEE) on Bogotá’s schoolchildren. The comprehension was assessed on 324 students, whereas the reproducibility was studied on a different random sample of 162 who were exposed twice to it. Reproducibility was assessed using both the Bland-Altman plot and the intra-class correlation coefficient (ICC). The validity was studied in a sample of 18 girls and 18 boys randomly selected, which completed the test - re-test study. The DEE derived from the questionnaire was compared with the laboratory measurement results of the peak oxygen uptake (Peak VO2) from ergo-spirometry and Leger Test. The reproducibility ICC was 0.96 (95% C.I. 0.95-0.97); by age categories 8-10, 0.94 (0.89-0. 97); 11-13, 0.98 (0.96- 0.99); 14-16, 0.95 (0.91-0.98). The ICC between mean TEE as estimated by the questionnaire and the direct and indirect Peak VO2 was 0.76 (0.66) (p<0.01); by age categories, 8-10, 11-13, and 14-16 were 0.89 (0.87), 0.76 (0.78) and 0.88 (0.80) respectively. The QAPACE questionnaire is reproducible and valid for estimating PA and showed a high correlation with the Peak VO2 uptake. Key pointsThe presence of a supervisor, the limited size of the group with the possibility of answering to their questions could explain the high reproducibility for this questionnaire.No study in the literature had directly addressed the issue of estimating a yearly average PA including school and vacation period.A two step procedure, in the population of schoolchildren of Bogotá, gives confidence in the use of the QAPACE questionnaire in a large epidemiological survey in related populations. PMID:24149485

  2. Asexual and sexual replication in sporulating organisms

    NASA Astrophysics Data System (ADS)

    Lee, Bohyun; Tannenbaum, Emmanuel

    2007-08-01

    Replication via sporulation is the replication strategy for all multicellular life, and may even be observed in unicellular life (such as with budding yeast). We consider diploid populations replicating via one of two possible sporulation mechanisms. (1) Asexual sporulation, whereby adult organisms produce single-celled diploid spores that grow into adults themselves. (2) Sexual sporulation, whereby adult organisms produce single-celled diploid spores that divide into haploid gametes. The haploid gametes enter a haploid “pool,” where they may recombine with other haploids to form a diploid spore that then grows into an adult. We consider a haploid fusion rate given by second-order reaction kinetics. We work with a simplified model where the diploid genome consists of only two chromosomes, each of which may be rendered defective with a single point mutation of the wild-type. We find that the asexual strategy is favored when the rate of spore production is high compared to the characteristic growth rate from a spore to a reproducing adult. Conversely, the sexual strategy is favored when the rate of spore production is low compared to the characteristic growth rate from a spore to a reproducing adult. As the characteristic growth time increases, or as the population density increases, the critical ratio of spore production rate to organism growth rate at which the asexual strategy overtakes the sexual one is pushed to higher values. Therefore, the results of this model suggest that, for complex multicellular organisms, sexual replication is favored at high population densities and low growth and sporulation rates.

  3. Reproducibility of optical coherence tomography airway imaging

    PubMed Central

    Kirby, Miranda; Ohtani, Keishi; Nickens, Taylor; Lisbona, Rosa Maria Lopez; Lee, Anthony M. D.; Shaipanich, Tawimas; Lane, Pierre; MacAulay, Calum; Lam, Stephen; Coxson, Harvey O.

    2015-01-01

    Optical coherence tomography (OCT) is a promising imaging technique to evaluate small airway remodeling. However, the short-term insertion-reinsertion reproducibility of OCT for evaluating the same bronchial pathway has yet to be established. We evaluated 74 OCT data sets from 38 current or former smokers twice within a single imaging session. Although the overall insertion-reinsertion airway wall thickness (WT) measurement coefficient of variation (CV) was moderate at 12%, much of the variability between repeat imaging was attributed to the observer; CV for repeated measurements of the same airway (intra-observer CV) was 9%. Therefore, reproducibility may be improved by introduction of automated analysis approaches suggesting that OCT has potential to be an in-vivo method for evaluating airway remodeling in future longitudinal and intervention studies. PMID:26601002

  4. Sexual selection affects local extinction and turnover in bird communities

    USGS Publications Warehouse

    Doherty, P.F., Jr.; Sorci, G.; Royle, J. Andrew; Hines, J.E.; Nichols, J.D.; Boulinier, T.

    2003-01-01

    Predicting extinction risks has become a central goal for conservation and evolutionary biologists interested in population and community dynamics. Several factors have been put forward to explain risks of extinction, including ecological and life history characteristics of individuals. For instance, factors that affect the balance between natality and mortality can have profound effects on population persistence. Sexual selection has been identified as one such factor. Populations under strong sexual selection experience a number of costs ranging from increased predation and parasitism to enhanced sensitivity to environmental and demographic stochasticity. These findings have led to the prediction that local extinction rates should be higher for species/populations with intense sexual selection. We tested this prediction by analyzing the dynamics of natural bird communities at a continental scale over a period of 21 years (1975-1996), using relevant statistical tools. In agreement with the theoretical prediction, we found that sexual selection increased risks of local extinction (dichromatic birds had on average a 23% higher local extinction rate than monochromatic species). However, despite higher local extinction probabilities, the number of dichromatic species did not decrease over the period considered in this study. This pattern was caused by higher local turnover rates of dichromatic species, resulting in relatively stable communities for both groups of species. Our results suggest that these communities function as metacommunities, with frequent local extinctions followed by colonization. Anthropogenic factors impeding dispersal might therefore have a significant impact on the global persistence of sexually selected species.

  5. Reproducibility of 3D chromatin configuration reconstructions.

    PubMed

    Segal, Mark R; Xiong, Hao; Capurso, Daniel; Vazquez, Mariel; Arsuaga, Javier

    2014-07-01

    It is widely recognized that the three-dimensional (3D) architecture of eukaryotic chromatin plays an important role in processes such as gene regulation and cancer-driving gene fusions. Observing or inferring this 3D structure at even modest resolutions had been problematic, since genomes are highly condensed and traditional assays are coarse. However, recently devised high-throughput molecular techniques have changed this situation. Notably, the development of a suite of chromatin conformation capture (CCC) assays has enabled elicitation of contacts-spatially close chromosomal loci-which have provided insights into chromatin architecture. Most analysis of CCC data has focused on the contact level, with less effort directed toward obtaining 3D reconstructions and evaluating the accuracy and reproducibility thereof. While questions of accuracy must be addressed experimentally, questions of reproducibility can be addressed statistically-the purpose of this paper. We use a constrained optimization technique to reconstruct chromatin configurations for a number of closely related yeast datasets and assess reproducibility using four metrics that measure the distance between 3D configurations. The first of these, Procrustes fitting, measures configuration closeness after applying reflection, rotation, translation, and scaling-based alignment of the structures. The others base comparisons on the within-configuration inter-point distance matrix. Inferential results for these metrics rely on suitable permutation approaches. Results indicate that distance matrix-based approaches are preferable to Procrustes analysis, not because of the metrics per se but rather on account of the ability to customize permutation schemes to handle within-chromosome contiguity. It has recently been emphasized that the use of constrained optimization approaches to 3D architecture reconstruction are prone to being trapped in local minima. Our methods of reproducibility assessment provide a means for comparing 3D reconstruction solutions so that we can discern between local and global optima by contrasting solutions under perturbed inputs. PMID:24519450

  6. Sexual Dysfunction and Infertility

    MedlinePLUS

    ... to have sex), arousal (your body undergoes the physical changes that allow you to have sex), and orgasm. ... treat sexual dysfunction? Your doctor will do a physical exam and ask you questions about your medical and sexual history. Important chemicals in your body, called hormones, affect your interest ...

  7. Sexuality, Power, and Politics.

    ERIC Educational Resources Information Center

    Hartsock, Nancy C. M.

    The source of contemporary attitudes toward sexuality, power, and politics is found in the literature of the ancient Greeks, specifically, Plato's "Republic" and "Symposium," Aristotle's "Politics," and the plays of Aeschylus and Aristophanes. The "Symposium" can be read as an account of how sexuality can be incorporated into the public life of…

  8. Sexual Harassment in Nursing.

    ERIC Educational Resources Information Center

    Duldt, Bonnie W.

    1982-01-01

    Sexual harassment in the workplace, specifically in nursing, is discussed. The impact of sexual harassment, characteristics of those commonly involved, the need for changing attitudes of men and women in the workplace, the factor of power in relationships, and ways to avoid legal suits are all examined. (CT)

  9. Human Sexuality Education Program.

    ERIC Educational Resources Information Center

    Claremont Univ. Center, CA.

    This program provides information to students about human sexual biology, behavior and attitudes. The primary intent of the workshops described is to provide fuller information and opportunity for self awareness to encourage participants to be more responsible as sexual beings, and to restructure their attitudes. The program presents the…

  10. Maternal Sexuality and Breastfeeding

    ERIC Educational Resources Information Center

    Bartlett, Alison

    2005-01-01

    In this paper I consider the ways in which lactation has been discussed as a form of maternal sexuality, and the implications this carries for our understanding of breastfeeding practices and sexuality. Drawing on knowledge constructed in the western world during the last half of the twentieth century, the paper identifies a shift between the…

  11. Sexual reproduction of the Hawaiian black coral Antipathes griggi (Cnidaria: Antipatharia)

    NASA Astrophysics Data System (ADS)

    Wagner, D.; Waller, R. G.; Montgomery, A. D.; Kelley, C. D.; Toonen, R. J.

    2012-09-01

    The Hawaiian black coral fishery has maintained steady catch levels for over 50 years. However, recent declines in the biomass of commercially valuable Hawaiian black corals question whether regulations need to be redefined for sustainable harvesting. Fishery management efforts are complicated by the limited information on the basic life history and reproduction of black corals. To address this knowledge gap, we used histological techniques to investigate sexual reproductive processes within Antipathes griggi, the dominant species targeted by the fishery. Our results indicate that A. griggi is likely gonochoric with a 1:1 sex ratio and has an annual reproductive cycle. Furthermore, the percentage of polyps containing gametes dropped continuously throughout the reproductive season, indicating that spawning occurs in successive events with greatest intensity between November and December. Current fishing regulations prohibit harvesting of colonies <90 cm in height in state waters, and colonies <120 cm in height in federal waters. This study indicates that ~80% meeting the state harvesting limit, and ~90% of colonies meeting the federal limit, are sexually mature. Therefore, increasing these minimum size harvesting limits would ensure that more colonies can reproduce before being exposed to fishing mortality. Although A. griggi can be found to depths of 100 m, it is rare below the 75 m depth limit at which commercial harvest occurs in Hawai`i. Thus, the supposed depth refuge from harvest does not really exist.

  12. A Framework for Reproducible Latent Fingerprint Enhancements

    PubMed Central

    Carasso, Alfred S.

    2014-01-01

    Photoshop processing1 of latent fingerprints is the preferred methodology among law enforcement forensic experts, but that appproach is not fully reproducible and may lead to questionable enhancements. Alternative, independent, fully reproducible enhancements, using IDL Histogram Equalization and IDL Adaptive Histogram Equalization, can produce better-defined ridge structures, along with considerable background information. Applying a systematic slow motion smoothing procedure to such IDL enhancements, based on the rapid FFT solution of a Lévy stable fractional diffusion equation, can attenuate background detail while preserving ridge information. The resulting smoothed latent print enhancements are comparable to, but distinct from, forensic Photoshop images suitable for input into automated fingerprint identification systems, (AFIS). In addition, this progressive smoothing procedure can be reexamined by displaying the suite of progressively smoother IDL images. That suite can be stored, providing an audit trail that allows monitoring for possible loss of useful information, in transit to the user-selected optimal image. Such independent and fully reproducible enhancements provide a valuable frame of reference that may be helpful in informing, complementing, and possibly validating the forensic Photoshop methodology.

  13. Death after Sexual Intercourse

    PubMed Central

    Braun, Christian T.; Ricklin, Meret E.; Pauli, Andreina; Ott, Daniel; Exadaktylos, Aristomenis K.; Pfortmueller, Carmen A.

    2015-01-01

    Sexuality is an essential aspect of quality of life. Nevertheless, sexual intercourse is physically challenging and leads to distinct changes in blood pressure, heart, and respiratory rate that may lead to vital complications. We present a case report of a 22-year-old female suffering from subarachnoid hemorrhage after sexual intercourse. The patient was immediately transported to hospital by emergency medical services and, after diagnosis, transferred to a tertiary hospital with neurosurgical expertise but died within 24?hours. After postcoital headaches, subarachnoid hemorrhage is the second most common cause of neurological complications of sexual intercourse and therefore patients admitted to an emergency department with headache after sexual intercourse should always be carefully evaluated by cerebral imaging. PMID:26697238

  14. New insights into the regulation of sexual reproduction in Closterium.

    PubMed

    Sekimoto, Hiroyuki; Abe, Jun; Tsuchikane, Yuki

    2012-01-01

    The genus Closterium, which is the closest unicellular relative to land plants, is the best-characterized charophycean green alga with respect to the process of sexual reproduction. In two representative heterothallic species, the steps and methods of intercellular communication were fully described. Glycoproteinaceous sex pheromones involved in the progress of these processes were physiologically and biochemically characterized and the corresponding genes were cloned. These pheromones function in most steps of sexual reproduction. For elucidating the mechanisms of sexual reproduction in detail, molecular tools such as expressed sequence tag, microarray analysis, and genetic transformation systems have been established, and whole genome analyses are ongoing. Finally, sexual reproductive isolation among mating groups was characterized, and the mechanism involved in this isolation was considered with respect to sex pheromones. In homothallic Closterium, the presence of a pheromone orthologous to the heterothallic type and possible sexual differentiation were also described, through the combination of closely related heterothallic cells. PMID:22608564

  15. Sexual selection accelerates signal evolution during speciation in birds

    PubMed Central

    Seddon, Nathalie; Botero, Carlos A.; Tobias, Joseph A.; Dunn, Peter O.; MacGregor, Hannah E. A.; Rubenstein, Dustin R.; Uy, J. Albert C.; Weir, Jason T.; Whittingham, Linda A.; Safran, Rebecca J.

    2013-01-01

    Sexual selection is proposed to be an important driver of diversification in animal systems, yet previous tests of this hypothesis have produced mixed results and the mechanisms involved remain unclear. Here, we use a novel phylogenetic approach to assess the influence of sexual selection on patterns of evolutionary change during 84 recent speciation events across 23 passerine bird families. We show that elevated levels of sexual selection are associated with more rapid phenotypic divergence between related lineages, and that this effect is restricted to male plumage traits proposed to function in mate choice and species recognition. Conversely, we found no evidence that sexual selection promoted divergence in female plumage traits, or in male traits related to foraging and locomotion. These results provide strong evidence that female choice and male–male competition are dominant mechanisms driving divergence during speciation in birds, potentially linking sexual selection to the accelerated evolution of pre-mating reproductive isolation. PMID:23864596

  16. Influences of clonality on plant sexual reproduction

    PubMed Central

    Barrett, Spencer C. H.

    2015-01-01

    Flowering plants possess an unrivaled diversity of mechanisms for achieving sexual and asexual reproduction, often simultaneously. The commonest type of asexual reproduction is clonal growth (vegetative propagation) in which parental genotypes (genets) produce vegetative modules (ramets) that are capable of independent growth, reproduction, and often dispersal. Clonal growth leads to an expansion in the size of genets and increased fitness because large floral displays increase fertility and opportunities for outcrossing. Moreover, the clonal dispersal of vegetative propagules can assist “mate finding,” particularly in aquatic plants. However, there are ecological circumstances in which functional antagonism between sexual and asexual reproductive modes can negatively affect the fitness of clonal plants. Populations of heterostylous and dioecious species have a small number of mating groups (two or three), which should occur at equal frequency in equilibrium populations. Extensive clonal growth and vegetative dispersal can disrupt the functioning of these sexual polymorphisms, resulting in biased morph ratios and populations with a single mating group, with consequences for fertility and mating. In populations in which clonal propagation predominates, mutations reducing fertility may lead to sexual dysfunction and even the loss of sex. Recent evidence suggests that somatic mutations can play a significant role in influencing fitness in clonal plants and may also help explain the occurrence of genetic diversity in sterile clonal populations. Highly polymorphic genetic markers offer outstanding opportunities for gaining novel insights into functional interactions between sexual and clonal reproduction in flowering plants. PMID:26195747

  17. Influences of clonality on plant sexual reproduction.

    PubMed

    Barrett, Spencer C H

    2015-07-21

    Flowering plants possess an unrivaled diversity of mechanisms for achieving sexual and asexual reproduction, often simultaneously. The commonest type of asexual reproduction is clonal growth (vegetative propagation) in which parental genotypes (genets) produce vegetative modules (ramets) that are capable of independent growth, reproduction, and often dispersal. Clonal growth leads to an expansion in the size of genets and increased fitness because large floral displays increase fertility and opportunities for outcrossing. Moreover, the clonal dispersal of vegetative propagules can assist "mate finding," particularly in aquatic plants. However, there are ecological circumstances in which functional antagonism between sexual and asexual reproductive modes can negatively affect the fitness of clonal plants. Populations of heterostylous and dioecious species have a small number of mating groups (two or three), which should occur at equal frequency in equilibrium populations. Extensive clonal growth and vegetative dispersal can disrupt the functioning of these sexual polymorphisms, resulting in biased morph ratios and populations with a single mating group, with consequences for fertility and mating. In populations in which clonal propagation predominates, mutations reducing fertility may lead to sexual dysfunction and even the loss of sex. Recent evidence suggests that somatic mutations can play a significant role in influencing fitness in clonal plants and may also help explain the occurrence of genetic diversity in sterile clonal populations. Highly polymorphic genetic markers offer outstanding opportunities for gaining novel insights into functional interactions between sexual and clonal reproduction in flowering plants. PMID:26195747

  18. Sexual Selection of Protamine 1 in Mammals.

    PubMed

    Lüke, Lena; Tourmente, Maximiliano; Roldan, Eduardo R S

    2016-01-01

    Protamines have a crucial role in male fertility. They are involved in sperm chromatin packaging and influence the shape of the sperm head and, hence, are important for sperm performance. Protamine structure is basic with numerous arginine-rich DNA-binding domains. Postcopulatory sexual selection is thought to play an important role in protamine sequence evolution and expression. Here, we analyze patterns of evolution and sexual selection (in the form of sperm competition) acting on protamine 1 gene sequence in 237 mammalian species. We assessed common patterns as well as differences between the major mammalian subclasses (Eutheria, Metatheria) and clades. We found that a high arginine content in protamine 1 associates with a lower sperm head width, which may have an impact on sperm swimming velocity. Increase in arginine content in protamine 1 across mammals appears to take place in a way consistent with sexual selection. In metatherians, increase in sequence length correlates with sexual selection. Differences in selective pressures on sequences and codon sites were observed between mammalian clades. Our study revealed a complex evolutionary pattern of protamine 1, with different selective constraints, and effects of sexual selection, between mammalian groups. In contrast, the effect of arginine content on head shape, and the possible involvement of sperm competition, was identified across all mammals. PMID:26429923

  19. ORIGINAL PAPER Reported Sexual Desire Predicts Men's Preferences for Sexually

    E-print Network

    Little, Tony

    investigating the relationship between sexual desire and sexual attraction have found that heterosexual women's reported sexual desire is positively cor- related with their reported attraction to both own- and opposite with their reported attraction to opposite-sex individuals only. These findings have led to the proposal that sexual

  20. Outcomes of Sexual Behaviors among Sexual Minority Youth

    ERIC Educational Resources Information Center

    Morgan, Elizabeth M.

    2014-01-01

    Very little is known about outcomes of sexual behavior for sexual minority youth. In this chapter, I review relevant literature and draw on findings from my own research to initiate an inquiry into this important topic. I begin with a brief overview of the range of sexual behaviors of sexual minority adolescents and young adults. Next, I describe…

  1. Polymorphism in sexual versus non-sexual disease transmission

    E-print Network

    Antonovics, Janis

    transmitted diseases (STDs) often consist of related strains that cause non- sexually transmitted transmission modes. For example, out of 108 sexually transmitted diseases (STDs) for which reasonable estimatesPolymorphism in sexual versus non-sexual disease transmission PETER H. THRALL AND JANIS ANTONOVICS

  2. Prenatal endocrine influences on sexual orientation and on sexually differentiated childhood behavior

    PubMed Central

    Hines, Melissa

    2012-01-01

    Both sexual orientation and sex-typical childhood behaviors, such as toy, playmate and activity preferences, show substantial sex differences, as well as substantial variability within each sex. In other species, behaviors that show sex differences are typically influenced by exposure to gonadal steroids, particularly testosterone and its metabolites, during early development (prenatally or neonatally). This article reviews the evidence regarding prenatal influences of gonadal steroids on human sexual orientation, as well as sex-typed childhood behaviors that predict subsequent sexual orientation. The evidence supports a role for prenatal testosterone exposure in the development of sex-typed interests in childhood, as well as in sexual orientation in later life, at least for some individuals. It appears, however, that other factors, in addition to hormones, play an important role in determining sexual orientation. These factors have not been well-characterized, but possibilities include direct genetic effects, and effects of maternal factors during pregnancy. Although a role for hormones during early development has been established, it also appears that there may be multiple pathways to a given sexual orientation outcome and some of these pathways may not involve hormones. PMID:21333673

  3. Sexual, fecundity, and viability selection on flower size and number in a sexually dimorphic plant.

    PubMed

    Delph, Lynda F; Herlihy, Christopher R

    2012-04-01

    The evolution of sexual dimorphism will depend on how sexual, fecundity and viability selection act within each sex, with the different forms of selection potentially operating in opposing directions. We examined selection in the dioecious plant Silene latifolia using planted arrays of selection lines that differed in flower size (small vs. large). In this species, a flower size/number trade-off exists within each sex, and males produce smaller and more numerous flowers than females. Moreover, floral traits are genetically correlated with leaf physiology. Sexual selection favoring males in the small-flower line occurred via greater overlap in the timing of flower output between males from this line and females. Fecundity selection favored males with high flower production, as siring success was proportionate to pollen production. Viability selection opposed sexual selection, favoring males from the large-flower line. In females, fecundity and viability selection operated in the same direction, favoring those from the large-flower line via greater seed production and survival. These results concur with the pattern of floral sexual dimorphism. Together with previous results they suggest that the outcome of the different forms of selection will be environmentally dependent, and therefore help to explain variation among populations in sexually dimorphic traits. PMID:22486695

  4. Reproducible quantitative proteotype data matrices for systems biology.

    PubMed

    Röst, Hannes L; Malmström, Lars; Aebersold, Ruedi

    2015-11-01

    Historically, many mass spectrometry-based proteomic studies have aimed at compiling an inventory of protein compounds present in a biological sample, with the long-term objective of creating a proteome map of a species. However, to answer fundamental questions about the behavior of biological systems at the protein level, accurate and unbiased quantitative data are required in addition to a list of all protein components. Fueled by advances in mass spectrometry, the proteomics field has thus recently shifted focus toward the reproducible quantification of proteins across a large number of biological samples. This provides the foundation to move away from pure enumeration of identified proteins toward quantitative matrices of many proteins measured across multiple samples. It is argued here that data matrices consisting of highly reproducible, quantitative, and unbiased proteomic measurements across a high number of conditions, referred to here as quantitative proteotype maps, will become the fundamental currency in the field and provide the starting point for downstream biological analysis. Such proteotype data matrices, for example, are generated by the measurement of large patient cohorts, time series, or multiple experimental perturbations. They are expected to have a large effect on systems biology and personalized medicine approaches that investigate the dynamic behavior of biological systems across multiple perturbations, time points, and individuals. PMID:26543201

  5. Effect of tropical storms on sexual and asexual reproduction in coral Pocillopora verrucosa subpopulations in the Gulf of California

    NASA Astrophysics Data System (ADS)

    Aranceta-Garza, F.; Balart, E. F.; Reyes-Bonilla, H.; Cruz-Hernández, P.

    2012-12-01

    Pocillopora verrucosa is a branching, reef-building coral, and a simultaneous hermaphrodite that reproduces sexually and asexually by fragmentation. In the Gulf of California, local P. verrucosa populations have mixed modes of reproduction which vary in frequency by site. Sexual and asexual reproductions were assessed using multi-locus genotypes deriving from six microsatellite loci at every location. Clone frequencies varied from 0.30 at Loreto to 0.96 in the San Lorenzo Channel. Isla Espíritu Santo and the San Lorenzo Channel were mostly asexual subpopulations, presented the lowest genotypic richness ( N g / N = 0.1-0.12) and genotypic diversity ( G o / G e = 0.04), and were dominated by one or two multi-loci genotypes ( G o / N g = 0.35-0.45). Loreto, El Portugués, and Cabo Pulmo were mostly sexual with high Ng/ N (0.80-0.74) and G o / G e (0.52-0.58) and did not show domination by a single multi-locus genotype ( G o / N g = 0.70-0.74). There was a significant relationship ( P < 0.05) between tropical storm frequency and the genotypic indexes of richness and diversity modeling an inverted U-shape, which indicates that the sites where storm frequencies were the highest had mostly clonal populations; sites exposed to intermediate or low storm frequencies had mostly sexual populations. The study included a restored area (San Lorenzo Channel) where genotypic analyses showed a high level of clonality similar to natural conditions occurring in a nearby subpopulation (Isla Espíritu Santo), which demonstrates the low natural genetic diversity of the area. This study showed that a species with mixed reproduction modes has different maintenance strategies at a regional and even local level among populations indicating the crucial role that storms play in population structure.

  6. Human Sexuality: Responsible Life Choices.

    ERIC Educational Resources Information Center

    Ryder, Verdene; Smith, Peggy B.

    This book provides a complete course in human sexuality. It can also be used to supplement a family living course. Text content provides current information for teaching high school students about sexuality issues. The text offers basic information on growth and development, sexual development, pregnancy, and birth. It explains the sexual decision…

  7. Evidence for no sexual isolation between Drosophila albomicans and D. nasuta

    PubMed Central

    Kim, Yong-Kyu; Phillips, Dennis R; Tao, Yun

    2013-01-01

    Sexual isolation, the reduced tendency to mate, is one of the reproductive barriers that prevent gene flow between different species. Various species-specific signals during courtship contribute to sexual isolation between species. Drosophila albomicans and D. nasuta are closely related species of the nasuta subgroup within the Drosophila immigrans group and are distributed in allopatry. We analyzed mating behavior and courtship as well as cuticular hydrocarbon profiles within and between species. Here, we report that these two species randomly mated with each other. We did not observe any sexual isolation between species or between strains within species by multiple-choice tests. Significant difference in the courtship index was detected between these two species, but males and females of both species showed no discrimination against heterospecific partners. Significant quantitative variations in cuticular hydrocarbons between these two species were also found, but the cuticular hydrocarbons appear to play a negligible role in both courtship and sexual isolation between these two species. In contrast to the evident postzygotic isolation, the lack of sexual isolation between these two species suggests that the evolution of premating isolation may lag behind that of the intergenomic incompatibility, which might be driven by intragenomic conflicts. PMID:23919152

  8. Open and reproducible global land use classification

    NASA Astrophysics Data System (ADS)

    Nüst, Daniel; Václavík, Tomáš; Pross, Benjamin

    2015-04-01

    Researchers led by the Helmholtz Centre for Environmental research (UFZ) developed a new world map of land use systems based on over 30 diverse indicators (http://geoportal.glues.geo.tu-dresden.de/stories/landsystemarchetypes.html) of land use intensity, climate and environmental and socioeconomic factors. They identified twelve land system archetypes (LSA) using a data-driven classification algorithm (self-organizing maps) to assess global impacts of land use on the environment, and found unexpected similarities across global regions. We present how the algorithm behind this analysis can be published as an executable web process using 52°North WPS4R (https://wiki.52north.org/bin/view/Geostatistics/WPS4R) within the GLUES project (http://modul-a.nachhaltiges-landmanagement.de/en/scientific-coordination-glues/). WPS4R is an open source collaboration platform for researchers, analysts and software developers to publish R scripts (http://www.r-project.org/) as a geo-enabled OGC Web Processing Service (WPS) process. The interoperable interface to call the geoprocess allows both reproducibility of the analysis and integration of user data without knowledge about web services or classification algorithms. The open platform allows everybody to replicate the analysis in their own environments. The LSA WPS process has several input parameters, which can be changed via a simple web interface. The input parameters are used to configure both the WPS environment and the LSA algorithm itself. The encapsulation as a web process allows integration of non-public datasets, while at the same time the publication requires a well-defined documentation of the analysis. We demonstrate this platform specifically to domain scientists and show how reproducibility and open source publication of analyses can be enhanced. We also discuss future extensions of the reproducible land use classification, such as the possibility for users to enter their own areas of interest to the system and generate summary statistics relating the particular area to the land system archetype. Such an extension demonstrates the advantages of open geoprocesses, because the user does not need to replicate the whole workflow, which included considerable data preparation steps, and can still access an analysis result tailored to his needs. The LSAs are the basis for science-based policy recommendations for sustainable land management and yield improvement at a global scale. The reproducibility of the study strengthens the scientific work and the open source platform allows scientists to adapt and extend it to provide new original contributions to sustainable land use management.

  9. Contributions to reproducible CPV outdoor power ratings

    NASA Astrophysics Data System (ADS)

    Besson, Pierre; Domínguez, César; Baudrit, Mathieu

    2014-09-01

    Methodologies that aim to obtain a reproducible power rating are still under discussion at the WG7 of the IEC and there is a need for feedback from real field application in order to validate or improve these methods. These procedures are evaluated through the outdoor rating of seven modules from four different CPV technologies, which have been measured at the CEA outdoor monitoring bench at the Institut National de l'Energie Solaire (INES) site. The benefit of introducing other procedural considerations is analyzed, namely the inclusion of spectrally-corrected irradiance, the utilization of lens temperature as a new parameter for regressions and the optimization of dataset filtering.

  10. Diversity of sexual systems within different lineages of the genus Silene

    PubMed Central

    Casimiro-Soriguer, Inés; Buide, Maria L.; Narbona, Eduardo

    2015-01-01

    Species and populations can be categorized by their sexual systems, depending on the spatial distribution of female and male reproductive structures within and among plants. Although a high diversity of sexual systems exists in Silene, their relative frequency at the genus and infrageneric level is unknown. Here, we carried out an extensive literature search for direct or indirect descriptions of sexual systems in Silene species. We found descriptions of sexual systems for 98 Silene species, where 63 and 35 correspond to the phylogenetically supported subgenera Silene and Behenantha, respectively. Hermaphroditism was the commonest sexual system (58.2 %), followed by dioecy (14.3 %), gynodioecy (13.3 %) and gynodioecy–gynomonoecy (i.e. hermaphroditic, female and gynomonoecious plants coexisting in the same population; 12.2 %). The presence of these sexual systems in both subgenera suggests their multiple origins. In 17 species, the description of sexual systems varied, and in most cases these differences corresponded to variations within or among populations. Interestingly, the poorly studied gynodioecy–gynomonoecy sexual system showed similar frequency to dioecy and gynodioecy in both subgenera. In addition, the incidence of gynodioecy–gynomonoecy was analysed in the species of section Psammophilae (Silene littorea, S. psammitis, S. adscendens and S. cambessedesii), in a survey of 26 populations across the distribution area of the species. The four species showed gynomonoecy–gynodioecy in most populations. Hermaphrodites were the most frequent morph, with a low number of females and gynomonoecious plants in all populations. The frequency of sexual morphs varied significantly among the studied populations but not among species. Female plants generally produced smaller numbers of flowers than hermaphroditic or gynomonoecious plants, and the percentages of female flowers per population were low. All these findings suggest that the gynodioecious–gynomonoecious sexual system in section Psammophilae is closer to hermaphroditism or gynomonoecy than gynodioecy. PMID:25862920

  11. Diversity of sexual systems within different lineages of the genus Silene.

    PubMed

    Casimiro-Soriguer, Inés; Buide, Maria L; Narbona, Eduardo

    2015-01-01

    Species and populations can be categorized by their sexual systems, depending on the spatial distribution of female and male reproductive structures within and among plants. Although a high diversity of sexual systems exists in Silene, their relative frequency at the genus and infrageneric level is unknown. Here, we carried out an extensive literature search for direct or indirect descriptions of sexual systems in Silene species. We found descriptions of sexual systems for 98 Silene species, where 63 and 35 correspond to the phylogenetically supported subgenera Silene and Behenantha, respectively. Hermaphroditism was the commonest sexual system (58.2 %), followed by dioecy (14.3 %), gynodioecy (13.3 %) and gynodioecy-gynomonoecy (i.e. hermaphroditic, female and gynomonoecious plants coexisting in the same population; 12.2 %). The presence of these sexual systems in both subgenera suggests their multiple origins. In 17 species, the description of sexual systems varied, and in most cases these differences corresponded to variations within or among populations. Interestingly, the poorly studied gynodioecy-gynomonoecy sexual system showed similar frequency to dioecy and gynodioecy in both subgenera. In addition, the incidence of gynodioecy-gynomonoecy was analysed in the species of section Psammophilae (Silene littorea, S. psammitis, S. adscendens and S. cambessedesii), in a survey of 26 populations across the distribution area of the species. The four species showed gynomonoecy-gynodioecy in most populations. Hermaphrodites were the most frequent morph, with a low number of females and gynomonoecious plants in all populations. The frequency of sexual morphs varied significantly among the studied populations but not among species. Female plants generally produced smaller numbers of flowers than hermaphroditic or gynomonoecious plants, and the percentages of female flowers per population were low. All these findings suggest that the gynodioecious-gynomonoecious sexual system in section Psammophilae is closer to hermaphroditism or gynomonoecy than gynodioecy. PMID:25862920

  12. Wired on steroids: sexual differentiation of the brain and its role in the expression of sexual partner preferences.

    PubMed

    Alexander, Brenda M; Skinner, Donal C; Roselli, Charles E

    2011-01-01

    The preference to seek out a sexual partner of the opposite sex is robust and ensures reproduction and survival of the species. Development of female-directed partner preference in the male is dependent on exposure of the developing brain to gonadal steroids synthesized during critical periods of sexual differentiation of the central nervous system. In the absence of androgen exposure, a male-directed partner preference develops. The development and expression of sexual partner preference has been extensively studied in rat, ferret, and sheep model systems. From these models it is clear that gonadal testosterone, often through estrogenic metabolites, cause both masculinization and defeminization of behavior during critical periods of brain development. Changes in the steroid environment during these critical periods result in atypical sexual partner preference. In this manuscript, we review the major findings which support the hypothesis that the organizational actions of sex steroids are responsible for sexual differentiation of sexual partner preferences in select non-human species. We also explore how this information has helped to frame our understanding of the biological influences on human sexual orientation and gender identity. PMID:22654808

  13. Species clarification of Ogasawara cockroaches which inhabit Japan.

    PubMed

    Komatsu, N; Kawakami, Y; Banzai, A; Ooi, H K; Uchida, A

    2015-03-01

    The so-called "Ogasawara cockroaches" were examined by morphological observations and by breeding experiments to elucidate their actual taxonomical status. Fourteen groups (isolate) of "Ogasawara cockroaches" collected from Iwoto-A, Iwoto-B, Hahajima, Chichijima, Nishijima, Nakodojima, Tokunoshima-A, Tokunoshima-B, Okinawato- A, Okinawa-B, Amamiooshima, Miyakojima, Ishigakijima and Hawaii, were bred and passaged in our laboratory. Cockroaches collected from the field were first reared individually and the sexes of their offspring examined. Cockroaches collected from Iwoto, Tokushima and Okinawa, were found to consist of two groups; those whose offspring were all female and the other whose offspring consist of both male and female. Cross-breeding experiments showed that individuals from the group that did not produce any male but only female offspring were parthenogenetic. On the contrary, the group that have bisexual individuals produced both male and female offspring in a ratio of 1:1. Our results show that the so-called "Ogasawara cockroaches" consist of 2 species, namely, Pycnoscelus surinamensis and Pycnoscelus indicus. There are areas in which both species co-habitated together and there are also areas in which either only one of the two species can be found. The group that reproduces only female offspring and only through parthenogenesis was identified as P. surinamensis. The group that reproduces heterosexually and produce male and female offspring was identified as P. indicus. Thus, the so-called "Ogasawara cockroaches" found in Japan actually consist of 2 species, namely, P. surinamensis and P. indicus, which can be differentiated using the solitary breeding method to demonstrate parthenogenesis in the former and the need for sexual reproduction in the latter. PMID:25801258

  14. Reproducibility of airway wall thickness measurements

    NASA Astrophysics Data System (ADS)

    Schmidt, Michael; Kuhnigk, Jan-Martin; Krass, Stefan; Owsijewitsch, Michael; de Hoop, Bartjan; Peitgen, Heinz-Otto

    2010-03-01

    Airway remodeling and accompanying changes in wall thickness are known to be a major symptom of chronic obstructive pulmonary disease (COPD), associated with reduced lung function in diseased individuals. Further investigation of this disease as well as monitoring of disease progression and treatment effect demand for accurate and reproducible assessment of airway wall thickness in CT datasets. With wall thicknesses in the sub-millimeter range, this task remains challenging even with today's high resolution CT datasets. To provide accurate measurements, taking partial volume effects into account is mandatory. The Full-Width-at-Half-Maximum (FWHM) method has been shown to be inappropriate for small airways1,2 and several improved algorithms for objective quantification of airway wall thickness have been proposed.1-8 In this paper, we describe an algorithm based on a closed form solution proposed by Weinheimer et al.7 We locally estimate the lung density parameter required for the closed form solution to account for possible variations of parenchyma density between different lung regions, inspiration states and contrast agent concentrations. The general accuracy of the algorithm is evaluated using basic tubular software and hardware phantoms. Furthermore, we present results on the reproducibility of the algorithm with respect to clinical CT scans, varying reconstruction kernels, and repeated acquisitions, which is crucial for longitudinal observations.

  15. Reproducibility Data on SUMMiT

    SciTech Connect

    Irwin, Lloyd; Jakubczak, Jay; Limary, Siv; McBrayer, John; Montague, Stephen; Smith, James; Sniegowski, Jeffry; Stewart, Harold; de Boer, Maarten

    1999-07-16

    SUMMiT (Sandia Ultra-planar Multi-level MEMS Technology) at the Sandia National Laboratories' MDL (Microelectronics Development Laboratory) is a standardized MEMS (Microelectromechanical Systems) technology that allows designers to fabricate concept prototypes. This technology provides four polysilicon layers plus three sacrificial oxide layers (with the third oxide layer being planarized) to enable fabrication of complex mechanical systems-on-a-chip. Quantified reproducibility of the SUMMiT process is important for process engineers as well as designers. Summary statistics for critical MEMS technology parameters such as film thickness, line width, and sheet resistance will be reported for the SUMMiT process. Additionally, data from Van der Pauw test structures will be presented. Data on film thickness, film uniformity and critical dimensions of etched line widths are collected from both process and monitor wafers during manufacturing using film thickness metrology tools and SEM tools. A standardized diagnostic module is included in each SWiT run to obtain post-processing parametric data to monitor run-to-run reproducibility such as Van der Pauw structures for measuring sheet resistance. This characterization of the SUMMiT process enables design for manufacturability in the SUMMiT technology.

  16. Causes of male sexual trait divergence in introduced populations of guppies.

    PubMed

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

    2014-02-01

    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

  17. Sexually Transmitted Infections

    MedlinePLUS

    ... D., M.P.H., FACOG, Commander, U.S. Public Health Service Commissioned Corps, Medical Officer, Sexually Transmitted Diseases Branch, Division of Microbiology and Infectious Diseases,National Institute of Allergy and ...

  18. Sexual Counseling and Therapy

    ERIC Educational Resources Information Center

    Hoch, Zwi

    1976-01-01

    The Ob/Gyn Department of Rambam University, Haifa, Israel, recently established a Center for Sexual Counseling, Therapy and Education. The Center's concept and format of therapy, and some preliminary observations, are presented. (Author)

  19. Sexuality and Dementia

    MedlinePLUS

    Sexuality and Dementia Printer-friendly version Coping with Changes in Your Intimate Relationship How has your relationship with your partner changed ... said Jerry, who cared for his wife with dementia. At a recent conference of the Caregiver Resource ...

  20. Sexually Transmitted Diseases

    MedlinePLUS

    Sexually transmitted diseases (STDs) are infections that you can get from having sex with someone who has the infection. The causes ... is no cure. Sometimes medicines can keep the disease under control. Correct usage of latex condoms greatly ...

  1. Understanding Sexual Violence

    MedlinePLUS

    ... and peeping. Other SV, including unwanted touching and rape, includes physical contact. Why is sexual violence a ... United States have experienced an attempted or complete rape during their college career. 2 • Nearly 1 in ...

  2. Understanding Sexual Violence

    MedlinePLUS

    ... prevent sexual violence, we need to know how big the problem is, where it is, and who it affects. CDC learns about a problem by gathering and studying data. These data are critical because they help us ...

  3. Rape (sexual assault) - overview

    MedlinePLUS

    Sex and rape; Date rape; Sexual assault ... Rape may occur between members of the same sex. This is more common in places such as prisons, military settings, and single-sex schools. People with physical or mental disabilities or ...

  4. Sexuality and Intellectual Disability

    MedlinePLUS

    ... or developmental disabilities have been thought to be asexual, having no need for loving and fulfilling relationships ... decision-making, including education about such issues as reproduction, marriage and family life, abstinence, safe sexual practices, ...

  5. Theories of Sexual Orientation.

    ERIC Educational Resources Information Center

    Storms, Michael D.

    1980-01-01

    Results indicated homosexuals, heterosexuals, and bisexuals did not differ within each sex on measures of masculinity and femininity. Strong support was obtained for the hypothesis that sexual orientation relates primarily to erotic fantasy orientation. (Author/DB)

  6. FAQ: Child Sexual Exploitation

    MedlinePLUS

    ... Support FAQ: Child Sexual Exploitation What is child pornography? Federal law (18 U.S.C. §2256(8)) defines ... person under the age of 18. Is child pornography a crime? It is a federal crime to ...

  7. Men and Sexual Trauma

    MedlinePLUS

    ... Topic Finder My Health e Vet Prescriptions Refills Crisis Prevention Mental Health PTSD Public Health Benefits General ... about sexual assault and men. A local rape crisis center may be able to refer men to ...

  8. Sexual Abuse of Children.

    ERIC Educational Resources Information Center

    Csapo, Marg

    1988-01-01

    Canadian reports and legislation are reviewed to highlight the school's role in prevention and reporting of suspicions of child sexual abuse. The vulnerability of handicapped children and child pornography are two areas of victimization emphasized. (Author/DB)

  9. Prevalence of Sexual Dysfunctions

    PubMed Central

    Simons, Jeffrey; Carey, Michael P.

    2008-01-01

    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

  10. Sexual selection targets cetacean pelvic bones.

    PubMed

    Dines, James P; Otárola-Castillo, Erik; Ralph, Peter; Alas, Jesse; Daley, Timothy; Smith, Andrew D; Dean, Matthew D

    2014-11-01

    Male genitalia evolve rapidly, probably as a result of sexual selection. Whether this pattern extends to the internal infrastructure that influences genital movements remains unknown. Cetaceans (whales and dolphins) offer a unique opportunity to test this hypothesis: since evolving from land-dwelling ancestors, they lost external hind limbs and evolved a highly reduced pelvis that seems to serve no other function except to anchor muscles that maneuver the penis. Here, we create a novel morphometric pipeline to analyze the size and shape evolution of pelvic bones from 130 individuals (29 species) in the context of inferred mating system. We present two main findings: (1) males from species with relatively intense sexual selection (inferred by relative testes size) tend to evolve larger penises and pelvic bones compared to their body length, and (2) pelvic bone shape has diverged more in species pairs that have diverged in inferred mating system. Neither pattern was observed in the anterior-most pair of vertebral ribs, which served as a negative control. This study provides evidence that sexual selection can affect internal anatomy that controls male genitalia. These important functions may explain why cetacean pelvic bones have not been lost through evolutionary time. PMID:25186496

  11. Sexual selection targets cetacean pelvic bones

    PubMed Central

    Dines, J. P.; Otárola-Castillo, E.; Ralph, P.; Alas, J.; Daley, T.; Smith, A. D.; Dean, M. D.

    2014-01-01

    Male genitalia evolve rapidly, probably as a result of sexual selection. Whether this pattern extends to the internal infrastructure that influences genital movements remains unknown. Cetaceans (whales and dolphins) offer a unique opportunity to test this hypothesis: since evolving from land-dwelling ancestors, they lost external hind limbs and evolved a highly reduced pelvis which seems to serve no other function except to anchor muscles that maneuver the penis. Here we create a novel morphometric pipeline to analyze the size and shape evolution of pelvic bones from 130 individuals (29 species) in the context of inferred mating system. We present two main findings: 1) males from species with relatively intense sexual selection (inferred by relative testes size) have evolved relatively large penises and pelvic bones compared to their body size, and 2) pelvic bone shape diverges more quickly in species pairs that have diverged in inferred mating system. Neither pattern was observed in the anterior-most pair of vertebral ribs, which served as a negative control. This study provides evidence that sexual selection can affect internal anatomy that controls male genitalia. These important functions may explain why cetacean pelvic bones have not been lost through evolutionary time. PMID:25186496

  12. Natural and sexual selection act on different axes of variation in avian plumage color

    PubMed Central

    Dunn, Peter O.; Armenta, Jessica K.; Whittingham, Linda A.

    2015-01-01

    The bright colors of birds are often attributed to sexual selection on males, but in many species both sexes are colorful and it has been long debated whether sexual selection can also explain this variation. We show that most evolutionary transitions in color have been toward similar plumage in both sexes, and the color of both sexes (for example, bright or dull) was associated with indices of natural selection (for example, habitat type), whereas sexual differences in color were primarily associated with indices of sexual selection on males (for example, polygyny and large testes size). Debate about the evolution of bird coloration can be resolved by recognizing that both natural and sexual selection have been influential, but they have generally acted on two different axes: sexual selection on an axis of sexual differences and natural selection on both sexes for the type of color (for example, bright or dull).

  13. Natural and sexual selection act on different axes of variation in avian plumage color.

    PubMed

    Dunn, Peter O; Armenta, Jessica K; Whittingham, Linda A

    2015-03-01

    The bright colors of birds are often attributed to sexual selection on males, but in many species both sexes are colorful and it has been long debated whether sexual selection can also explain this variation. We show that most evolutionary transitions in color have been toward similar plumage in both sexes, and the color of both sexes (for example, bright or dull) was associated with indices of natural selection (for example, habitat type), whereas sexual differences in color were primarily associated with indices of sexual selection on males (for example, polygyny and large testes size). Debate about the evolution of bird coloration can be resolved by recognizing that both natural and sexual selection have been influential, but they have generally acted on two different axes: sexual selection on an axis of sexual differences and natural selection on both sexes for the type of color (for example, bright or dull). PMID:26601146

  14. Intralocus sexual conflict and environmental stress.

    PubMed

    Berger, David; Grieshop, Karl; Lind, Martin I; Goenaga, Julieta; Maklakov, Alexei A; Arnqvist, Göran

    2014-08-01

    Intralocus sexual conflict (IaSC) occurs when selection at a given locus favors different alleles in males and females, placing a fundamental constraint on adaptation. However, the relative impact of IaSC on adaptation may become reduced in stressful environments that expose conditionally deleterious mutations to selection. The genetic correlation for fitness between males and females (rMF ) provides a quantification of IaSC across the genome. We compared IaSC at a benign (29°C) and a stressful (36°C) temperature by estimating rMF s in two natural populations of the seed beetle Callosobruchus maculatus using isofemale lines. In one population, we found substantial IaSC under benign conditions signified by a negative rMF (-0.51) and, as predicted, a significant reduction of IaSC under stress signified by a reversed and positive rMF (0.21). The other population displayed low IaSC at both temperatures (rMF : 0.38; 0.40). In both populations, isofemale lines harboring alleles beneficial to males but detrimental to females at benign conditions tended to show overall low fitness under stress. These results offer support for low IaSC under stress and suggest that environmentally sensitive and conditionally deleterious alleles that are sexually selected in males mediate changes in IaSC. We discuss implications for adaptive evolution in sexually reproducing populations. PMID:24766035

  15. Insect Cuticular Hydrocarbons as Dynamic Traits in Sexual Communication

    PubMed Central

    Ingleby, Fiona C.

    2015-01-01

    Recent research has demonstrated extensive within-species variation in pheromone expression in insect species, contrary to the view that pheromones are largely invariant within species. In fact, many studies on insect cuticular hydrocarbons (CHCs) show that pheromones can be highly dynamic traits that can express significant short-term plasticity across both abiotic and social environments. It is likely that this variability in CHC expression contributes to their important role in sexual signaling and mate choice. In this review, I discuss CHC plasticity and how this might influence sexual communication. I also highlight two important avenues for future research: examining plasticity in how individuals respond to CHC signals, and testing how sexual communication varies across abiotic and social environments. PMID:26463413

  16. The reproducibility of intrapartum cardiotocogram assessments.

    PubMed Central

    Beaulieu, M. D.; Fabia, J.; Leduc, B.; Brisson, J.; Bastide, A.; Blouin, D.; Gauthier, R. J.; Lalonde, A.

    1982-01-01

    Five obstetrician-gynecologists experienced in fetal monitoring assessed 150 intrapartum cardiotocograms obtained with an external transducer. There were three successive blind readings, the first two without any clinical data apart from gestational age. The reviewers indicated whether the tracings showed definite, possible or no abnormalities. The interpretations given by each reviewer for any one tracing were fairly consistent, but they varied markedly from one reviewer to another. The proportion of tracings interpreted as normal ranged from 39% to 74%, and the proportion assessed as abnormal ranged from 3% to 43%. All five observers agreed on the interpretation of 29% of the tracings. Inter-reviewer reproducibility scarcely changed when clinical data were provided. These findings emphasize the need to evaluate all methods of fetal monitoring before they become widespread. PMID:7104902

  17. PSYCHOLOGY. Estimating the reproducibility of psychological science.

    PubMed

    2015-08-28

    Reproducibility is a defining feature of science, but the extent to which it characterizes current research is unknown. We conducted replications of 100 experimental and correlational studies published in three psychology journals using high-powered designs and original materials when available. Replication effects were half the magnitude of original effects, representing a substantial decline. Ninety-seven percent of original studies had statistically significant results. Thirty-six percent of replications had statistically significant results; 47% of original effect sizes were in the 95% confidence interval of the replication effect size; 39% of effects were subjectively rated to have replicated the original result; and if no bias in original results is assumed, combining original and replication results left 68% with statistically significant effects. Correlational tests suggest that replication success was better predicted by the strength of original evidence than by characteristics of the original and replication teams. PMID:26315443

  18. Is Grannum grading of the placenta reproducible?

    NASA Astrophysics Data System (ADS)

    Moran, Mary; Ryan, John; Brennan, Patrick C.; Higgins, Mary; McAuliffe, Fionnuala M.

    2009-02-01

    Current ultrasound assessment of placental calcification relies on Grannum grading. The aim of this study was to assess if this method is reproducible by measuring inter- and intra-observer variation in grading placental images, under strictly controlled viewing conditions. Thirty placental images were acquired and digitally saved. Five experienced sonographers independently graded the images on two separate occasions. In order to eliminate any technological factors which could affect data reliability and consistency all observers reviewed images at the same time. To optimise viewing conditions ambient lighting was maintained between 25-40 lux, with monitors calibrated to the GSDF standard to ensure consistent brightness and contrast. Kappa (?) analysis of the grades assigned was used to measure inter- and intra-observer reliability. Intra-observer agreement had a moderate mean ?-value of 0.55, with individual comparisons ranging from 0.30 to 0.86. Two images saved from the same patient, during the same scan, were each graded as I, II and III by the same observer. A mean ?-value of 0.30 (range from 0.13 to 0.55) indicated fair inter-observer agreement over the two occasions and only one image was graded consistently the same by all five observers. The study findings confirmed the lack of reproducibility associated with Grannum grading of the placenta despite optimal viewing conditions and highlight the need for new methods of assessing placental health in order to improve neonatal outcomes. Alternative methods for quantifying placental calcification such as a software based technique and 3D ultrasound assessment need to be explored.

  19. Empirical Bayes for Group (DCM) Studies: A Reproducibility Study

    PubMed Central

    Litvak, Vladimir; Garrido, Marta; Zeidman, Peter; Friston, Karl

    2015-01-01

    This technical note addresses some key reproducibility issues in the dynamic causal modelling of group studies of event related potentials. Specifically, we address the reproducibility of Bayesian model comparison (and inferences about model parameters) from three important perspectives namely: (i) reproducibility with independent data (obtained by averaging over odd and even trials); (ii) reproducibility over formally distinct models (namely, classic ERP and canonical microcircuit or CMC models); and (iii) reproducibility over inversion schemes (inversion of the grand average and estimation of group effects using empirical Bayes). Our hope was to illustrate the degree of reproducibility one can expect from DCM when analysing different data, under different models with different analyses.

  20. Empirical Bayes for Group (DCM) Studies: A Reproducibility Study.

    PubMed

    Litvak, Vladimir; Garrido, Marta; Zeidman, Peter; Friston, Karl

    2015-01-01

    This technical note addresses some key reproducibility issues in the dynamic causal modelling of group studies of event related potentials. Specifically, we address the reproducibility of Bayesian model comparison (and inferences about model parameters) from three important perspectives namely: (i) reproducibility with independent data (obtained by averaging over odd and even trials); (ii) reproducibility over formally distinct models (namely, classic ERP and canonical microcircuit or CMC models); and (iii) reproducibility over inversion schemes (inversion of the grand average and estimation of group effects using empirical Bayes). Our hope was to illustrate the degree of reproducibility one can expect from DCM when analysing different data, under different models with different analyses. PMID:26733846

  1. Reproducing Natural Spider Silks’ Copolymer Behavior in Synthetic Silk Mimics

    PubMed Central

    An, Bo; Jenkins, Janelle E.; Sampath, Sujatha; Holland, Gregory P.; Hinman, Mike; Yarger, Jeffery L.; Lewis, Randolph

    2012-01-01

    Dragline silk from orb-weaving spiders is a copolymer of two large proteins, major ampullate spidroin 1 (MaSp1) and 2 (MaSp2). The ratio of these proteins is known to have a large variation across different species of orb-weaving spiders. NMR results from gland material of two different species of spiders, N. clavipes and A. aurantia, indicates that MaSp1 proteins are more easily formed into ?-sheet nanostructures, while MaSp2 proteins form random coil and helical structures. To test if this behavior of natural silk proteins could be reproduced by recombinantly produced spider silk mimic protein, recombinant MaSp1/MaSp2 mixed fibers as well as chimeric silk fibers from MaSp1 and MaSp2 sequences in a single protein were produced based on the variable ratio and conserved motifs of MaSp1 and MaSp2 in native silk fiber. Mechanical properties, solid-state NMR, and XRD results of tested synthetic fibers indicate the differing roles of MaSp1 and MaSp2 in the fiber and verify the importance of postspin stretching treatment in helping the fiber to form the proper spatial structure. PMID:23110450

  2. Sexual functioning and sexual satisfaction among women who report a history of childhood and/or adolescent sexual abuse.

    PubMed

    Leonard, Leah M; Iverson, Katherine M; Follette, Victoria M

    2008-01-01

    This study examined the relationship between sexual functioning, sexual satisfaction, and predictor variables (experiential avoidance, relationship violence, relationship satisfaction, anger, and psychological distress) in 22 women reporting a history of childhood and/or adolescent sexual abuse. Sexual satisfaction correlated significantly with all predictor variables. Sexual functioning correlated significantly with relationship violence only. Interestingly, sexual satisfaction and sexual functioning were not significantly correlated. Two hierarchical regression equations, using sexual satisfaction and sexual functioning as dependent variables and using the same predictor variables, were tested. Results suggest that different factors may account for sexual satisfaction and sexual functioning and more research is needed to clarify this relationship. PMID:18770109

  3. Is pedophilia a sexual orientation?

    PubMed

    Seto, Michael C

    2012-02-01

    In this article, I address the question of whether pedophilia in men can be construed as a male sexual orientation, and the implications for thinking of it in this way for scientific research, clinical practice, and public policy. I begin by defining pedophilia and sexual orientation, and then compare pedophilia (as a potential sexual orientation with regard to age) to sexual orientations with regard to gender (heterosexuality, bisexuality, and homosexuality), on the bases of age of onset, correlations with sexual and romantic behavior, and stability over time. I conclude with comments about the potential social and legal implications of conceptualizing pedophilia as a type of sexual orientation in males. PMID:22218786

  4. The herring gull complex is not a ring species.

    PubMed Central

    Liebers, Dorit; de Knijff, Peter; Helbig, Andreas J.

    2004-01-01

    Under what circumstances speciation in sexually reproducing animals can occur without geographical disjunction is still controversial. According to the ring-species model, a reproductive barrier may arise through 'isolation by distance' when peripheral populations of a species meet after expanding around some uninhabitable barrier. The classical example of this kind of speciation is the herring gull (Larus argentatus) complex, with a circumpolar distribution in the Northern Hemisphere. Based on mitochondrial DNA variation among 21 gull taxa, we show that members of this complex differentiated largely in allopatry following multiple vicariance and long-distance-colonization events, not primarily through isolation by distance. Reproductive isolation evolved more rapidly between some lineages than between others, irrespective of their genetic distance. Extant taxa are the result of divergent as well as reticulate evolution between two ancestral lineages originally separated in a North Atlantic refugium and a continental Eurasian refugium, respectively. Continental birds expanded along the entire north Eurasian coast and via Beringia into North America. Contrary to the ring-species model, we find no genetic evidence for a closure of the circumpolar ring through colonization of Europe by North American herring gulls. However, closure of the ring in the opposite direction may be imminent, with lesser black-backed gulls about to colonize North America. PMID:15255043

  5. Sexual recombination as a tool for engineering industrial Penicillium chrysogenum strains.

    PubMed

    Dahlmann, Tim A; Böhm, Julia; Becker, Kordula; Kück, Ulrich

    2015-11-01

    The recent discovery and functional characterization of opposite mating-type loci in the industrial penicillin producer Penicillium chrysogenum demonstrated their regulatory role in sexual as well as asexual development. Subsequent experiments further showed that a sexual life cycle can be induced in P. chrysogenum that was for long believed to reproduce exclusively by asexual propagation. Finally, crossing of wild type and production strains resulted in the generation of recombinant ascospore isolates. We predict from these recent findings that recombinant progeny for industrial applications can be obtained by sexual crossings and discuss experimental difficulties that occur when parental strains with karyotype heterogeneity are used for mating. PMID:25993917

  6. Sex and the singular DM domain: insights into sexual regulation, evolution and plasticity

    PubMed Central

    Matson, Clinton K.; Zarkower, David

    2013-01-01

    Most animals reproduce sexually, but the genetic and molecular mechanisms that determine the eventual sex of each embryo vary remarkably. DM domain genes, which are related to the insect gene doublesex, are integral to sexual development and its evolution in many metazoans. Recent studies of DM domain genes reveal mechanisms by which new sexual dimorphisms have evolved in invertebrates and show that one gene, Dmrt1, was central to multiple evolutionary transitions between sex-determining mechanisms in vertebrates. In addition, Dmrt1 coordinates a surprising array of distinct cell fate decisions in the mammalian gonad and even guards against transdifferentiation of male cells into female cells in the adult testis. PMID:22310892

  7. 46 CFR 56.30-3 - Piping joints (reproduces 110).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56...APPURTENANCES Selection and Limitations of Piping Joints § 56.30-3 Piping joints (reproduces 110). The type of piping...

  8. 46 CFR 56.30-3 - Piping joints (reproduces 110).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56...APPURTENANCES Selection and Limitations of Piping Joints § 56.30-3 Piping joints (reproduces 110). The type of piping...

  9. 46 CFR 56.30-3 - Piping joints (reproduces 110).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56...APPURTENANCES Selection and Limitations of Piping Joints § 56.30-3 Piping joints (reproduces 110). The type of piping...

  10. 46 CFR 56.30-3 - Piping joints (reproduces 110).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56...APPURTENANCES Selection and Limitations of Piping Joints § 56.30-3 Piping joints (reproduces 110). The type of piping...

  11. Multivariate intralocus sexual conflict in seed beetles.

    PubMed

    Berger, David; Berg, Elena C; Widegren, William; Arnqvist, Göran; Maklakov, Alexei A

    2014-12-01

    Intralocus sexual conflict (IaSC) is pervasive because males and females experience differences in selection but share much of the same genome. Traits with integrated genetic architecture should be reservoirs of sexually antagonistic genetic variation for fitness, but explorations of multivariate IaSC are scarce. Previously, we showed that upward artificial selection on male life span decreased male fitness but increased female fitness compared with downward selection in the seed beetle Callosobruchus maculatus. Here, we use these selection lines to investigate sex-specific evolution of four functionally integrated traits (metabolic rate, locomotor activity, body mass, and life span) that collectively define a sexually dimorphic life-history syndrome in many species. Male-limited selection for short life span led to correlated evolution in females toward a more male-like multivariate phenotype. Conversely, males selected for long life span became more female-like, implying that IaSC results from genetic integration of this suite of traits. However, while life span, metabolism, and body mass showed correlated evolution in the sexes, activity did not evolve in males but, surprisingly, did so in females. This led to sexual monomorphism in locomotor activity in short-life lines associated with detrimental effects in females. Our results thus support the general tenet that widespread pleiotropy generates IaSC despite sex-specific genetic architecture. PMID:25213393

  12. Sexual conflict promotes speciation in insects

    PubMed Central

    Arnqvist, Göran; Edvardsson, Martin; Friberg, Urban; Nilsson, Tina

    2000-01-01

    Speciation rates among extant lineages of organisms vary extensively, but our understanding of the causes of this variation and, therefore, the processes of speciation is still remarkably incomplete. Both theoretical and empirical studies have indicated that sexual selection is important in speciation, but earlier discussions have focused almost exclusively on the potential role of female mate choice. Recent findings of postmating reproductive conflicts of interest between the sexes suggest a quite different route to speciation. Such conflicts may lead to perpetual antagonistic coevolution between males and females and may thus generate rapid evolutionary divergence of traits involved in reproduction. Here, we assess this hypothesis by contrasting pairs of related groups of insect species differing in the opportunity for postmating sexual conflict. Groups where females mate with many males exhibited speciation rates four times as high as in related groups where females mate only once. Our results not only highlight the general importance of postmating sexual selection in speciation, but also support the recent suggestion that sexual conflict is a key engine of speciation. PMID:10984538

  13. Sexual Desire and the Female Sexual Function Index (FSFI): A Sexual Desire Cutpoint for Clinical Interpretation of the FSFI

    E-print Network

    Meston, Cindy

    Sexual Desire and the Female Sexual Function Index (FSFI): A Sexual Desire Cutpoint for Clinical T Introduction. A validated cutpoint for the total Female Sexual Function Index scale score exists to classify, Rosen RC, Brewer JV, Meston CM, Brotto LA, Wiegel M, and Sand M. Sexual desire and the female sexual

  14. Prolonged sexual abstinence after childbirth: gendered norms and perceived family health risks. Focus group discussions in a Tanzanian suburb

    PubMed Central

    2013-01-01

    Background Prolonged sexual abstinence after childbirth is a socio-cultural practice with health implications, and is described in several African countries, including Tanzania. This study explored discourses on prolonged postpartum sexual abstinence in relation to family health after childbirth in low-income suburbs of Dar es Salaam, Tanzania. Methods Data for the discourse analysis were collected through focus group discussions with first-time mothers and fathers and their support people in Ilala, Dar es Salaam, Tanzania. Results In this setting, prolonged sexual abstinence intended at promoting child health was the dominant discourse in the period after childbirth. Sexual relations after childbirth involved the control of sexuality for ensuring family health and avoiding the social implications of non-adherence to sexual abstinence norms. Both abstinence and control were emphasised more with regard to women than to men. Although the traditional discourse on prolonged sexual abstinence for protecting child health was reproduced in Ilala, some modern aspects such as the use of condoms and other contraceptives prevailed in the discussion. Conclusion Discourses on sexuality after childbirth are instrumental in reproducing gender-power inequalities, with women being subjected to more restrictions and control than men are. Thus, interventions that create openness in discussing sexual relations and health-related matters after childbirth and mitigate gendered norms suppressing women and perpetuating harmful behaviours are needed. The involvement of males in the interventions would benefit men, women, and children through improving the gender relations that promote family health. PMID:23316932

  15. If you have experienced sexual harassment, sexual assault,

    E-print Network

    and Counseling YWCA Rape Crisis Hotline and non-emergency assistance related to sexual assault Barnes LGBT Crisis Intervention and Suicide Prevention SARAH Sexual Assault and Rape Anonymous Helpline (314

  16. Policy on Sexual Harassment Policy on Sexual Harassment

    E-print Network

    Sridhar, Srinivas

    , hostile or offensive environment for that individual's employment, education, benefits, housing, offensive, intimidating, or humiliating to male or female workers may also constitute sexual harassment advances ­ whether they involve physical touching or not; Sexual epithets, jokes, written or oral

  17. The Impact of Sexual Orientation on Sexuality and Sexual Practices in North American Medical Students

    PubMed Central

    Breyer, Benjamin N.; Smith, James F.; Eisenberg, Michael L.; Ando, Kathryn A.; Rowen, Tami S.; Shindel, Alan W.

    2013-01-01

    Introduction There has been limited investigation of the sexuality and sexual dysfunction in non-heterosexual subjects by the sexual medicine community. Additional research in these populations is needed. Aims To investigate and compare sexuality and sexual function in students of varying sexual orientations. Methods An internet-based survey on sexuality was administered to medical students in North American between the months of February and July of 2008. Main Outcome Measures All subjects provided information on their ethnodemographic characteristics, sexual orientation, and sexual history. Subjects also completed a series of widely-utilized instruments for the assessment of human sexuality (International Index of Erectile Function [IIEF], Female Sexual Function Index [FSFI], Premature Ejaculation Diagnostic Tool [PEDT], Index of Sex Life [ISL]). Results There were 2,276 completed responses to the question on sexual orientation. 13.2% of male respondents and 4.7% of female respondents reported a homosexual orientation; 2.5% of male and 5.7% of female respondents reported a bisexual orientation. Many heterosexual males and females reported same-sex sexual experiences (4% and 10%, respectively). Opposite-sex experiences were very common in the male and female homosexual population (37% and 44%, respectively). The prevalence of premature ejaculation (PEDT > 8) was similar among heterosexual and homosexual men (16% and 17%, P = 0.7, respectively). Erectile dysfunction (IIEF-EF < 26) was more common in homosexual men relative to heterosexual men (24% vs. 12%, P = 0.02). High risk for female sexual dysfunction (FSFI < 26.55) was more common in heterosexual and bisexual women compared with lesbians (51%, 45%, and 29%, respectively, P = 0.005). Conclusion In this survey of highly educated young professionals, numerous similarities and some important differences in sexuality and sexual function were noted based on sexual orientation. It is unclear whether the dissimilarities represent differing relative prevalence of sexual problems or discrepancies in patterns of sex behavior and interpretation of the survey questions. PMID:20384941

  18. Psychiatric disorders and sexual dysfunction.

    PubMed

    Waldinger, Marcel D

    2015-01-01

    Sexual problems are highly prevalent among patients with psychiatric disorders. They may be caused by the psychopathology of the psychiatric disorder but also by its pharmacotherapy. Both positive symptoms (e.g., psychosis, hallucinations) as well as negative symptoms (e.g., anhedonia) of schizophrenia may negatively interfere with interpersonal and sexual relationships. Atypical antipsychotics have fewer sexual side-effects than the classic antipsychotics. Mood disorders may affect libido, sexual arousal, orgasm, and erectile function. With the exception of bupropion, agomelatine, mirtazapine, vortioxetine, amineptine, and moclobemide, all antidepressants cause sexual side-effects. Selective serotonin reuptake inhibitors (SSRIs) may particularly delay ejaculation and female orgasm, but also can cause decreased libido and erectile difficulties. SSRI-induced sexual side-effects are dose-dependent and reversible. Very rarely, their sexual side-effects persist after SSRI discontinuation. This is often preceded by genital anesthesia. Some personality characteristics are a risk factor for sexual dysfunction. Also patients with eating disorders may suffer from sexual difficulties. So far, research into psychotropic-induced sexual side-effects suffers from substantial methodologic limitations. Patients tend not to talk with their clinician about their sexual life. Psychiatrists and other doctors need to take the initiative to talk about the patient's sexual life in order to become informed about potential medication-induced sexual difficulties. PMID:26003261

  19. On the evolutionary origins of differences in sexual preferences

    PubMed Central

    Ryabko, Daniil; Reznikova, Zhanna

    2015-01-01

    A novel explanation of the evolutionary process leading to the appearance of differences in sexual preferences is proposed. The explanation is fully general: it is not specific to any particular type of sexual preferences, nor to any species or population. It shows how different sexual preferences can appear in any large group-living population in which sexual selection is sufficiently strong in each sex. The main idea is that the lack of interest toward a member of the opposite sex may be interpreted as a signal of popularity, and thus of reproductive success. It is then boosted by the Fisher runaway process far beyond the point where it becomes costly, resulting in a generalized trait—lack of interest toward the opposite sex. If the interest diverts toward other targets then different sexual preferences emerge. This hypothesis is placed into the context of other works on different sexual preferences in animals; supporting evidence from the literature is reviewed and additional research needed to confirm or refute the hypothesis in any given species is outlined. PMID:26052290

  20. Sexually acquired hepatitis

    PubMed Central

    Brook, M

    2002-01-01

    Objectives: To assess current knowledge of sexually transmitted viral hepatitis in relation to epidemiology, clinical presentation, management, and diagnosis with particular reference to resource-poor settings. Method: A search of published literature identified through Medline from 1966 to October 2001, the Cochrane Library, and reference lists taken from each article obtained. Textword and MeSH searches for hepatitis A, B, C, D, E, G, delta, GB virus, GBV-C, and TT virus were linked to searches under the textword terms sex$, prevent$, and MeSH subheadings, microbiology, complications, drug therapy, therapy, diagnosis, epidemiology, transmission, and prevention and control. Conclusions: In heterosexual relationships, hepatitis B is readily transmitted sexually and hepatitis C and D less so, with no evidence for sexual transmission of hepatitis A. Hepatitis types A‘D are all transmissible sexually in male homosexual relationships under certain conditions. In resource-poor countries sexual transmission is generally only a significant route of transmission for hepatitis B. PMID:12181458

  1. Wilson Bull., 112(4), 2000, pp. 457466 SEXUAL SIZE DIMORPHISM OF THE MUSK DUCK

    E-print Network

    Afton, Alan D.

    457 Wilson Bull., 112(4), 2000, pp. 457­466 SEXUAL SIZE DIMORPHISM OF THE MUSK DUCK KEVIN G. Mc of a lek-displaying diving duck from Australia, the Musk Duck (Biziura lobata). Like other lek-displaying species, Musk Ducks exhibit extreme sexual size di- morphism in addition to structural dimorphism. Body

  2. Sexual size dimorphism in mammals Patrik Lindenfors, John L. Gittleman, and Kate E. Jones

    E-print Network

    Enquist, Magnus

    CHAPTER 2 Sexual size dimorphism in mammals Patrik Lindenfors, John L. Gittleman, and Kate E. Jones in mammals using body-mass measurements for 1370 mammalian species, constituting almost 30% of those­male competition as a driver of male-biased sexual dimorphism in mammals. Since theoretical models predict

  3. Sexual Selection Continues to Shape Human Evolution, With Men Becoming More

    E-print Network

    Lummaa, Virpi

    and an increase prevalence of monogamy, natural and sexual selection is still significantly shaping human Magazine. "We have shown advances have not challenged the fact that our species is still evolving, just populations, and likely still occurs, so humans continue to be affected by both natural and sexual selection

  4. Gender, Religiosity, Sexual Activity, Sexual Knowledge, and Attitudes Toward Controversial Aspects of Sexuality.

    PubMed

    Sümer, Zeynep Hatipo?lu

    2015-12-01

    The purpose of this study is to examine the role of gender, religiosity, sexual activity, and sexual knowledge in predicting attitudes toward controversial aspects of sexuality among Turkish university students. Participants were 162 female and 135 male undergraduate students who were recruited on a volunteer basis from an urban state university in Turkey. The SKAT-A Attitude Scale along with background information form, sexual activities inventory, and sexual knowledge scale were administered to the participants. Simultaneous multiple regression analyses revealed that religiosity, particularly attendance to religious services was the most significant predictor in explaining university students' attitudes toward masturbation, abortion, homosexuality, pornography, and sexual coercion. PMID:24510128

  5. Sexual Coercion Content in 21 Sexuality Education Curricula.

    ERIC Educational Resources Information Center

    Beyer, Christine E.; Ogletree, Roberta J.

    1998-01-01

    Examined adolescent sexuality-education curricula for information on coercion (date rape, stranger rape, pressure, incest, sexual harassment, unwanted/inappropriate touch, and exploitation/victimization). Exploitation/victimization and pressure received the greatest attention. Sexual harassment was not covered in any of the curricula. Results…

  6. Association of Sexual Revictimization with Sexuality and Psychological Function

    ERIC Educational Resources Information Center

    Miner, Michael H.; Flitter, Jill M. Klotz; Robinson, Beatrice E.

    2006-01-01

    This study explores the associations of sexual revictimization (experiencing sexual abuse in childhood and adulthood) in a sample of 230 African American women who are low-income. Data indicate that women who experience sexual revictimization are more at risk for emotional stress and psychological pathology than women with no history of abuse. In…

  7. Sexual compulsion – Relationship with sex, attachment and sexual orientation

    PubMed Central

    KATZ, LICHEN; EBERHARDT, HILA; COHEN, KOBY; LEJOYEUX, MICHEL

    2015-01-01

    Background and aims Sexual addiction, also known as hypersexual disorder, is associated with serious psychosocial problems for many people. Methods This study used questionnaires to investigate the effects of gender, sexual orientation and attachment (avoidance and anxiety) on sexual compulsion among 100 heterosexual and homosexual men and women. Results A positive correlation was found between anxious attachment and sexual compulsivity (r = 0.46; p < 0.01) and a positive correlation between avoidant attachment and sexual compulsivity (r = 0.39; p ? 0.01) in all participants. Secondly, an analysis of covariance showed a gender by sexual orientation interaction effect [F(1, 103) = 6.39, p < 0.01] but no attachment effect on sexual compulsivity. A follow-up comparison showed that lesbian women had higher rates of sexual compulsivity than heterosexual women [t (2, 50) = 5.08, p < 0.001] whereas there was non-significant difference in sexual compulsivity between homosexual and heterosexual men [t (2, 50) = 1.30, p = N.S.]. Discussion The results provide preliminary evidence for an association between attachment and sexual compulsivity and the effects of gender and sexual orientation on sexual compulsivity. PMID:25786496

  8. Reproducibility of neuroimaging analyses across operating systems.

    PubMed

    Glatard, Tristan; Lewis, Lindsay B; Ferreira da Silva, Rafael; Adalat, Reza; Beck, Natacha; Lepage, Claude; Rioux, Pierre; Rousseau, Marc-Etienne; Sherif, Tarek; Deelman, Ewa; Khalili-Mahani, Najmeh; Evans, Alan C

    2015-01-01

    Neuroimaging pipelines are known to generate different results depending on the computing platform where they are compiled and executed. We quantify these differences for brain tissue classification, fMRI analysis, and cortical thickness (CT) extraction, using three of the main neuroimaging packages (FSL, Freesurfer and CIVET) and different versions of GNU/Linux. We also identify some causes of these differences using library and system call interception. We find that these packages use mathematical functions based on single-precision floating-point arithmetic whose implementations in operating systems continue to evolve. While these differences have little or no impact on simple analysis pipelines such as brain extraction and cortical tissue classification, their accumulation creates important differences in longer pipelines such as subcortical tissue classification, fMRI analysis, and cortical thickness extraction. With FSL, most Dice coefficients between subcortical classifications obtained on different operating systems remain above 0.9, but values as low as 0.59 are observed. Independent component analyses (ICA) of fMRI data differ between operating systems in one third of the tested subjects, due to differences in motion correction. With Freesurfer and CIVET, in some brain regions we find an effect of build or operating system on cortical thickness. A first step to correct these reproducibility issues would be to use more precise representations of floating-point numbers in the critical sections of the pipelines. The numerical stability of pipelines should also be reviewed. PMID:25964757

  9. SEXUALLY TRANSMITTED DISEASES SURVEILLANCE SYSTEM

    EPA Science Inventory

    The Sexually Transmitted Disease Surveillance System presents statistics and trends for sexually transmitted diseases (STDs). Data demonstrate details which provide information about STD morbidity in the United States, STD prevalence with subgroups and populations which are the f...

  10. Helping Teens Resist Sexual Pressure

    MedlinePLUS

    ... Listen Espańol Text Size Email Print Share Helping Teens Resist Sexual Pressure Article Body Teens are more ... younger the first time they had intercourse. Helping Teens Resist Sexual Pressure “The pressure on teenagers to ...

  11. Bystanders' Reactions to Sexual Harassment 

    E-print Network

    Benavides Espinoza, Claudia

    2010-07-14

    Sexual harassment is associated with negative consequences for victims and bystanders. Because 9 in 10 victims do not report harassment, understanding bystanders' reactions to sexual harassment is important. Thus, my dissertation?s purpose...

  12. Evidence for maintenance of sex determinants but not of sexual stages in red yeasts, a group of early diverged basidiomycetes

    PubMed Central

    2011-01-01

    Background The red yeasts are an early diverged group of basidiomycetes comprising sexual and asexual species. Sexuality is based on two compatible mating types and sexual identity is determined by MAT loci that encode homeodomain transcription factors, peptide pheromones and their receptors. The objective of the present study was to investigate the presence and integrity of MAT genes throughout the phylogenetic diversity of red yeasts belonging to the order Sporidiobolales. Results We surveyed 18 sexual heterothallic and self-fertile species and 16 asexual species. Functional pheromone receptor homologues (STE3.A1 and STE3.A2) were found in multiple isolates of most of the sexual and asexual species. For each of the two mating types, sequence comparisons with whole-genome data indicated that synteny tended to be conserved along the pheromone receptor region. For the homeodomain transcription factor, likelihood methods suggested that diversifying selection acting on the self/non-self recognition region promotes diversity in sexual species, while rapid evolution seems to be due to relaxed selection in asexual strains. Conclusions The majority of both sexual and asexual species of red yeasts have functional pheromone receptors and homeodomain homologues. This and the frequent existence of asexual strains within sexual species, makes the separation between sexual and asexual species imprecise. Events of loss of sexuality seem to be recent and frequent, but not uniformly distributed within the Sporidiobolales. Loss of sex could promote speciation by fostering the emergence of asexual lineages from an ancestral sexual stock, but does not seem to contribute to the generation of exclusively asexual lineages that persist for a long time. PMID:21880139

  13. Associations between youth homelessness, sexual offenses, sexual victimization, and sexual risk behaviors: a systematic literature review.

    PubMed

    Heerde, Jessica A; Scholes-Balog, Kirsty E; Hemphill, Sheryl A

    2015-01-01

    Homeless youth commonly report engaging in sexual risk behaviors. These vulnerable young people also frequently report being sexually victimized. This systematic review collates, summarizes, and appraises published studies of youth investigating relationships between homelessness, perpetration of sexual offenses, experience of sexual victimization, and engagement in sexual risk behavior. A systematic search of seventeen psychology, health, and social science electronic databases was conducted. Search terms included "homeless*," "youth," "offend*," "victimization," "crime," "rape," "victim*," and "sex crimes." Thirty-eight studies were identified that met the inclusion criteria. Findings showed homeless youth commonly report being raped and sexually assaulted, fear being sexually victimized, and engage in street prostitution and survival sex. Rates of victimization and sexual risk behavior were generally higher for females. Given the paucity of longitudinal studies and limitations of current studies, it is unclear whether homelessness is prospectively associated with sexual victimization or engagement in sexual risk behavior, and whether such associations vary cross nationally and as a function of time and place. Future prospective research examining the influence of the situational context of homelessness is necessary to develop a better understanding of how homelessness influences the perpetration of sexual offenses, experience of sexual victimization, and engagement in sexual risk behavior among homeless youth. PMID:25411128

  14. Sexual selection for indicators of intelligence.

    PubMed

    Miller, G

    2000-01-01

    Many traits in many species have evolved through sexual selection specifically to function as 'fitness indicators' that reveal good genes and good health. Sexually selected fitness indicators typically show (1) higher coefficients of phenotypic and genetic variation than survival traits, (2) at least moderate genetic heritabilities and (3) positive correlations with many aspects of an animal's general condition, including body size, body symmetry, parasite resistance, longevity and freedom from deleterious mutations. These diagnostic criteria also appear to describe human intelligence (the g factor). This paper argues that during human evolution, mate choice by both sexes focused increasingly on intelligence as a major heritable component of biological fitness. Many human-specific behaviours (such as conversation, music production, artistic ability and humour) may have evolved principally to advertise intelligence during courtship. Though these mental adaptations may be modular at the level of psychological functioning, their efficiencies may be tightly intercorrelated because they still tap into common genetic and neurophysiological variables associated with fitness itself. Although the g factor (like the superordinate factor of fitness itself) probably exists in all animal species, humans evolved an unusually high degree of interest in assessing each other's intelligence during courtship and other social interactions--and, consequently, a unique suite of highly g-loaded mental adaptations for advertising their intelligence to one another through linguistic and cultural interaction. This paper includes nine novel, testable predictions about human intelligence derived from sexual selection theory. PMID:11276907

  15. Meiosis completion and various sperm responses lead to unisexual and sexual reproduction modes in one clone of polyploid Carassius gibelio

    PubMed Central

    Zhang, Jun; Sun, Min; Zhou, Li; Li, Zhi; Liu, Zhen; Li, Xi-Yin; Liu, Xiao-Li; Liu, Wei; Gui, Jian-Fang

    2015-01-01

    Unisexual polyploid vertebrates are commonly known to reproduce by gynogenesis, parthenogenesis, or hybridogenesis. One clone of polyploid Carassius gibelio has been revealed to possess multiple modes of unisexual gynogenesis and sexual reproduction, but the cytological and developmental mechanisms have remained unknown. In this study, normal meiosis completion was firstly confirmed by spindle co-localization of ?-tubulin and Spindlin. Moreover, three types of various nuclear events and development behaviors were revealed by DAPI staining and BrdU-incorporated immunofluorescence detection during the first mitosis in the fertilized eggs by three kinds of different sperms. They include normal sexual reproduction in response to sperm from the same clone male, typical unisexual gynogenesis in response to sperm from the male of another species Cyprinus carpio, and an unusual hybrid-similar development mode in response to sperm from another different clone male. Based on these findings, we have discussed cytological and developmental mechanisms on multiple reproduction modes in the polyploid fish, and highlighted evolutionary significance of meiosis completion and evolutionary consequences of reproduction mode diversity in polyploid vertebrates. PMID:26042995

  16. Sexual selection in fungi.

    PubMed

    Nieuwenhuis, B P S; Aanen, D K

    2012-12-01

    The significance of sexual selection, the component of natural selection associated with variation in mating success, is well established for the evolution of animals and plants, but not for the evolution of fungi. Even though fungi do not have separate sexes, most filamentous fungi mate in a hermaphroditic fashion, with distinct sex roles, that is, investment in large gametes (female role) and fertilization by other small gametes (male role). Fungi compete to fertilize, analogous to 'male-male' competition, whereas they can be selective when being fertilized, analogous to female choice. Mating types, which determine genetic compatibility among fungal gametes, are important for sexual selection in two respects. First, genes at the mating-type loci regulate different aspects of mating and thus can be subject to sexual selection. Second, for sexual selection, not only the two sexes (or sex roles) but also the mating types can form the classes, the members of which compete for access to members of the other class. This is significant if mating-type gene products are costly, thus signalling genetic quality according to Zahavi's handicap principle. We propose that sexual selection explains various fungal characteristics such as the observed high redundancy of pheromones at the B mating-type locus of Agaricomycotina, the occurrence of multiple types of spores in Ascomycotina or the strong pheromone signalling in yeasts. Furthermore, we argue that fungi are good model systems to experimentally study fundamental aspects of sexual selection, due to their fast generation times and high diversity of life cycles and mating systems. PMID:23163326

  17. Sexual selection drives evolution and rapid turnover of male gene expression

    PubMed Central

    Harrison, Peter W.; Wright, Alison E.; Zimmer, Fabian; Dean, Rebecca; Montgomery, Stephen H.; Pointer, Marie A.; Mank, Judith E.

    2015-01-01

    The profound and pervasive differences in gene expression observed between males and females, and the unique evolutionary properties of these genes in many species, have led to the widespread assumption that they are the product of sexual selection and sexual conflict. However, we still lack a clear understanding of the connection between sexual selection and transcriptional dimorphism, often termed sex-biased gene expression. Moreover, the relative contribution of sexual selection vs. drift in shaping broad patterns of expression, divergence, and polymorphism remains unknown. To assess the role of sexual selection in shaping these patterns, we assembled transcriptomes from an avian clade representing the full range of sexual dimorphism and sexual selection. We use these species to test the links between sexual selection and sex-biased gene expression evolution in a comparative framework. Through ancestral reconstruction of sex bias, we demonstrate a rapid turnover of sex bias across this clade driven by sexual selection and show it to be primarily the result of expression changes in males. We use phylogenetically controlled comparative methods to demonstrate that phenotypic measures of sexual selection predict the proportion of male-biased but not female-biased gene expression. Although male-biased genes show elevated rates of coding sequence evolution, consistent with previous reports in a range of taxa, there is no association between sexual selection and rates of coding sequence evolution, suggesting that expression changes may be more important than coding sequence in sexual selection. Taken together, our results highlight the power of sexual selection to act on gene expression differences and shape genome evolution. PMID:25831521

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

    ERIC Educational Resources Information Center

    Randolph, Mary E.; Reddy, Diane M.

    2006-01-01

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

  19. [Sexuality in Ancient Egypt].

    PubMed

    Androutsos, G; Marketos, S

    1994-10-01

    The present article explores the sexuality in ancient Egypt. In particular in this article are presented the ways of concubinage (marriage, concubinage, adultery), the incest, loves of the pharaohs and of the common people, the freedom of choice in garments, the status of the hetairas and of the whores, the sexual perversions (male and female homosexuality, necrophilia, sodomism, bestiality, rape, masturbation, exhibitionism), the operations of the genitals (circumcision, excision, castration) and finally the level of knowledge in gynaecology, fertility, contraception and obstetrics that even today demands our admiration. PMID:7858632

  20. Ethnicity and sexuality

    E-print Network

    Nagel, Joane

    2000-01-01

    and types of sexual activity, see Kinsey et al 1948, 1953, Masters & Johnson 1966, 1970, Michael et al 1994, Laumann et al 1994). Some of the most interesting contemporary work deconstructing and challeng- ing assumptions about the nature and content..., Jones 1997), adultery appears to be a fairly common phenomenon in marriages and other monogamous relationships (e.g, 20% to 50% of respondents report extra-monogamous sexual activity; see Kinsey et al 1948, 1953, Michael et al 1994). In fact, high rates...

  1. Sexual Health in Prime Time

    ERIC Educational Resources Information Center

    Taverner, William J.

    2006-01-01

    The term "sexual health" is often used in sexuality education without any concrete, operational definition, and students are left to ascertain the meaning for themselves. In the absence of a clear definition, students may adopt diverse or narrow understandings of this vague term, without learning the full scope of everything that sexual health…

  2. The "Right" Sexuality for Girls

    ERIC Educational Resources Information Center

    Lamb, Sharon

    2008-01-01

    Feminist researchers in psychology and education have been theorizing about the kind of sexuality girls ought to have. They are not afraid to investigate morality and what makes a good life. While they explore the meaning and cultural context of girls' sexual development, the good sexual life they describe may be an elusive ideal that, in the end,…

  3. Experimental challenges to reproduce seismic fault motion

    NASA Astrophysics Data System (ADS)

    Shimamoto, T.

    2011-12-01

    This presentation briefly reviews scientific and technical development in the studies of intermediate to high-velocity frictional properties of faults and summarizes remaining technical challenges to reproduce nucleation to growth processes of large earthquakes in laboratory. Nearly 10 high-velocity or low to high-velocity friction apparatuses have been built in the last several years in the world and it has become possible now to produce sub-plate velocity to seismic slip rate in a single machine. Despite spreading of high-velocity friction studies, reproducing seismic fault motion at high P and T conditions to cover the entire seismogenic zone is still a big challenge. Previous studies focused on (1) frictional melting, (2) thermal pressurization, and (3) high-velocity gouge behavior without frictional melting. Frictional melting process was solved as a Stefan problem with very good agreement with experimental results. Thermal pressurization has been solved theoretically based on measured transport properties and has been included successfully in the modeling of earthquake generation. High-velocity gouge experiments in the last several years have revealed that a wide variety of gouges exhibit dramatic weakening at high velocities (e.g., Di Toro et al., 2011, Nature). Most gouge experiments were done under dry conditions partly to separate gouge friction from the involvement of thermal pressurization. However, recent studies demonstrated that dehydration or degassing due to mineral decomposition can occur during seismic fault motion. Those results not only provided a new view of looking at natural fault zones in search of geological evidence of seismic fault motion, but also indicated that thermal pressurization and gouge weakening can occur simultaneously even in initially dry gouge. Thus experiments with controlled pore pressure are needed. I have struggled to make a pressure vessel for wet high-velocity experiments in the last several years. A technical difficulty was how to absorb hydrodynamic shock due to abrupt fault motion in the vessel, and this was overcome by pressurizing water in the vessel, acting as pore fluid, using pressurized gas (in other words using gas as a cushion). I will report preliminary experimental results on high-velocity rock-on-rock friction under pore-water pressure. Other technical challenges are (i) how to produce step-change in velocity to see if the framework of rate-and-state friction law holds in high-velocity regime, (ii) how to conduct high-velocity friction experiments in hydrothermal conditions to study frictional properties relevant to slow slip and low-frequency tremors, and (iii) how to conduct high-velocity friction experiments at high normal stresses. The first task became possible with a low to high-velocity apparatus in Beijing and a few other machines, and I will show some preliminary results. There is no fundamental difficulty in (ii) since O-ring is enough to seal piston rotating at a high speed. However, (iii) will be the hardest because of severe thermal fracturing of host rocks that limits the axial stress. Use of aluminum sleeve made it possible to apply the normal stress to about 30 MPa, but new device and a high motor power is needed to go higher normal stress.

  4. Toy model for the adaptive origins of the sexual orientation continuum

    E-print Network

    Skinner, Brian

    2015-01-01

    Same-sex sexual behavior is ubiquitous in the animal kingdom, but its adaptive origins remain a prominent puzzle. Here I suggest the possibility that same-sex sexual behavior arises as a consequence of the competition between an evolutionary drive for a wide diversity in traits, which improves the adaptability of a species, and a drive for sexual dichotomization of traits, which promotes opposite-sex attraction and increases the rate of reproduction. A simple analytical "toy model" is proposed for describing this tradeoff. The model exhibits a number of interesting features, and suggests a simple mathematical form for describing the sexual orientation continuum.

  5. Host plant specialization driven by sexual selection.

    PubMed

    Quental, Tiago B; Patten, Manus M; Pierce, Naomi E

    2007-06-01

    We propose a new mechanism based on sexual selection to explain the evolution of diet breadth in insects. More specifically, we show that mate choice in females for certain diet-derived male pheromones can be exploited by maternal effect genes that preferentially place offspring on a specific host plant, resulting in specialization. Our analytical model also suggests that the process is more likely to occur with species that show male-congregating mating strategies, such as lekking and hilltopping. The model offers a new explanation for the similarity between the composition of male lepidopteran pheromones and the chemistry of their host plants and also suggests a novel mechanism of host plant shift. This is the first time that sexual selection has been proposed to drive host plant specialization and the first time that a mechanism with selection acting solely on the adult stage has been shown to be capable of determining larval feeding habits. PMID:17479468

  6. The relationship between sexual selection and sexual conflict.

    PubMed

    Kokko, Hanna; Jennions, Michael D

    2014-09-01

    Evolutionary conflicts of interest arise whenever genetically different individuals interact and their routes to fitness maximization differ. Sexual selection favors traits that increase an individual's competitiveness to acquire mates and fertilizations. Sexual conflict occurs if an individual of sex A's relative fitness would increase if it had a "tool" that could alter what an individual of sex B does (including the parental genes transferred), at a cost to B's fitness. This definition clarifies several issues: Conflict is very common and, although it extends outside traits under sexual selection, sexual selection is a ready source of sexual conflict. Sexual conflict and sexual selection should not be presented as alternative explanations for trait evolution. Conflict is closely linked to the concept of a lag load, which is context-dependent and sex-specific. This makes it possible to ask if one sex can "win." We expect higher population fitness if females win. PMID:25038050

  7. Televised sexual content and parental mediation: Influences on adolescent sexuality

    PubMed Central

    Fisher, Deborah A.; Hill, Douglas L.; Grube, Joel W.; Bersamin, Melina M.; Walker, Samantha; Gruber, Enid L.

    2011-01-01

    Little research has been conducted to examine the influence of exposure to televised sexual content on adolescent sexuality or how parental intervention may reduce negative effects of viewing such content. This study uses self-report data from 1,012 adolescents to investigate the relations among exposure to sexually suggestive programming, parental mediation strategies, and three types of adolescent sexuality outcomes: participation in oral sex and sexual intercourse, future intentions to engage in these behaviors, and sex expectancies. As predicted, exposure to sexual content was associated with an increased likelihood of engaging in sexual behaviors, increased intentions to do so in the future, and more positive sex expectancies. Often, parental mediation strategies were a significant factor in moderating these potential media influences. PMID:21546986

  8. Women's History of Sexual Abuse, Their Sexuality, and Sexual Self-Schemas

    ERIC Educational Resources Information Center

    Meston, Cindy M.; Rellini, Alessandra H.; Heiman, Julia R.

    2006-01-01

    In this study, the authors assessed 48 female survivors of child sexual abuse (CSA) and 71 female control participants using measures of adult sexual function, psychological function (i.e., depression and anxiety), and sexual self-schemas. The primary purpose of this study was to examine whether differences existed between women with and without a…

  9. Childhood Sexual Abuse Moderates the Association between Sexual Functioning and Sexual Distress in Women

    ERIC Educational Resources Information Center

    Stephenson, Kyle R.; Hughan, Corey P.; Meston, Cindy M.

    2012-01-01

    Objective: To assess the degree to which a history of childhood sexual abuse (CSA) moderates the association between sexual functioning and sexual distress in women. Method: Women with (n = 105, M age = 33.71, 66.1% Caucasian) and without (n = 71, M age = 32.63, 74.7% Caucasian) a history of CSA taking part in a larger clinical trial completed…

  10. Serious Games for Sexual Health.

    PubMed

    Shegog, Ross; Brown, Katherine; Bull, Sheana; Christensen, John L; Hieftje, Kimberly; Jozkowski, Kristen N; Ybarra, Michele L

    2015-04-01

    Program developers and researchers in the sexual health domain have increasingly embraced technological trends as they emerge. With the emergence of serious game applications to impact health behaviors, a natural step for research enquiry will be the investigation of serious games for sexual health education. We invited a panel of sexual health researchers who are working at the intersection of sexual health behavior change and technology applications to comment on the place of serious games in furthering the field of sexual health. The panel grappled with six questions. PMID:26181800

  11. Semiautomated, Reproducible Batch Processing of Soy

    NASA Technical Reports Server (NTRS)

    Thoerne, Mary; Byford, Ivan W.; Chastain, Jack W.; Swango, Beverly E.

    2005-01-01

    A computer-controlled apparatus processes batches of soybeans into one or more of a variety of food products, under conditions that can be chosen by the user and reproduced from batch to batch. Examples of products include soy milk, tofu, okara (an insoluble protein and fiber byproduct of soy milk), and whey. Most processing steps take place without intervention by the user. This apparatus was developed for use in research on processing of soy. It is also a prototype of other soy-processing apparatuses for research, industrial, and home use. Prior soy-processing equipment includes household devices that automatically produce soy milk but do not automatically produce tofu. The designs of prior soy-processing equipment require users to manually transfer intermediate solid soy products and to press them manually and, hence, under conditions that are not consistent from batch to batch. Prior designs do not afford choices of processing conditions: Users cannot use previously developed soy-processing equipment to investigate the effects of variations of techniques used to produce soy milk (e.g., cold grinding, hot grinding, and pre-cook blanching) and of such process parameters as cooking times and temperatures, grinding times, soaking times and temperatures, rinsing conditions, and sizes of particles generated by grinding. In contrast, the present apparatus is amenable to such investigations. The apparatus (see figure) includes a processing tank and a jacketed holding or coagulation tank. The processing tank can be capped by either of two different heads and can contain either of two different insertable mesh baskets. The first head includes a grinding blade and heating elements. The second head includes an automated press piston. One mesh basket, designated the okara basket, has oblong holes with a size equivalent to about 40 mesh [40 openings per inch (.16 openings per centimeter)]. The second mesh basket, designated the tofu basket, has holes of 70 mesh [70 openings per inch (.28 openings per centimeter)] and is used in conjunction with the press-piston head. Supporting equipment includes a soy-milk heat exchanger for maintaining selected coagulation temperatures, a filter system for separating okara from other particulate matter and from soy milk, two pumps, and various thermocouples, flowmeters, level indicators, pressure sensors, valves, tubes, and sample ports

  12. [Sexuality and pregnancy].

    PubMed

    Sueiro, E; Gayoso, P; Perdiz, C; Doval, J L

    1998-10-15

    206 randomly selected women in the 6th or 7th month of pregnancy participating in childbirth preparation classes at a center in Ourense, Spain, between January 1993 and January 1995, responded to anonymous questionnaires regarding their sexual behavior during pregnancy. The women were 28 years old on average, married, with secondary education, and employed in skilled jobs or as housewives. 88% were urban. 78% were childless. 93% stated the pregnancy was desired and 91% that it was normal. 73% of the pregnancies were attended by a gynecologist, 23% by a family doctor, and the rest by both. 63% of the women did not ask their physician about sexual activity during pregnancy. 26% did ask questions; 47% about sexual relations during pregnancy, 21% about whether the fetus would be harmed, and 13% about when relations should be discontinued. In an average week, 13% did not have coitus, 24% did so once, 28% twice, and 15% 3 times. 11% did not respond. 38% of the women responding reported always and 7% never reaching orgasm. 28% reported their sexual activity always included coitus and 29% that it almost always did so. 14% reported masturbating, 74% reported not masturbating, and 13% did not respond. PMID:9833348

  13. Storying childhood sexual abuse.

    PubMed

    Draucker, Claire Burke; Martsolf, Donna S

    2008-08-01

    A theoretical framework that explains how survivors of childhood sexual abuse tell others about their abuse experiences is presented. Data are drawn from open-ended interviews conducted with 74 individuals who experienced ongoing childhood sexual abuse by a family member or close acquaintance. Grounded theory methods were used to develop the framework. The psychosocial problem shared by the participants is that childhood sexual abuse both demands and defies explanation. The core psychosocial process used in response to this problem is storying childhood sexual abuse. The framework includes five processes, and the stories associated with each process vary in their nature and function. The processes and associated stories are (a) starting the story: the story-not-yet-told, (b) coming out with the story: the story-first-told, (c) shielding the story: the story-as-secret, (d) revising the story: the story-as-account, and (e) sharing the story: the story-as-message. Clinical applications of the framework are discussed. PMID:18650560

  14. Child Sexual Abuse

    MedlinePLUS

    ... worthlessness and an abnormal or distorted view of sex. The child may become withdrawn and mistrustful of adults, and ... Violent Behavior In Children and Adolescents The Depressed Child Teen Suicide Talking To Your Kids About Sex Self-Injury In Adolescents Responding To Child Sexual ...

  15. Fighting Campus Sexual Assault

    ERIC Educational Resources Information Center

    Tolman, Warren

    2014-01-01

    When President Obama points out, correctly, that young women stand a better chance of being sexually assaulted on a college campus than in the world outside, we have a problem that needs to be addressed not simply on campus, but at the highest levels of government. Author Warren Tolman strongly believes that the Massachusetts Office of Attorney…

  16. Rescheduling Child Sexual Trajectories

    ERIC Educational Resources Information Center

    Yuill, Richard

    2008-01-01

    The author comments on Diederik Janssen's essay "ReQueering Queer Youth Development: A Post-Developmental Approach to Childhood and Pedagogy," commenting that Janssen's analysis can inform both both materialist and post-structuralist understandings of children's sexuality by shifting focus from children as fetishized objects or as a group…

  17. [The sexuality by Marańón].

    PubMed

    Clavero Núńez, José Antonio

    2010-01-01

    It is noticeable that he always had an interest in sexuality Marańón. It must be noted that at the time this included a series of processes that now have become separated from it, as all human reproduction, both from a social standpoint as a scientist or political issues and problems in speaking so very active. But specifically, referring to the current concept of sexuality, much to Marańón investigated because, following the ideas of Freud, then in vogue, I wanted to know the importance that the hormones, newly discovered, had on the brain and the human personality. It is quite possible to believe that there is a brain chemistry that modulate the individual's character, against the prevailing idea among psychiatrists of his time. So his research with adrenaline on the behavior had a huge impact. Interested in the morphological evolution of sex and sexuality from birth to old age, remain valid provided knowledge about the process of sexual maturation and decline, menopause, or rather the climacteric, as rightly he called that period of time. He also made a deep study and systematization of the pathology adel origin and evolution of sex, in which he listed as intersex, both anatomically and functionally and psychic. Because he was always interested in the relationship of human behavior, the development of your body or endocrine constitution and personality. This is reflected in their psychobiographies as the paradigm "Bioassay of Henry IV of Castile and his time". PMID:21877403

  18. Sexually Transmitted Diseases (STDs)

    MedlinePLUS

    ... enabling JavaScript. Top Banner Content Area Skip Content Marketing Share this: Main Content Area Sexually Transmitted Diseases STDs are an important global health priority because of their devastating impact on women and infants and their inter-relationships with HIV/AIDS. STDs and HIV are linked ...

  19. Difference in Plumage Color Used in Species Recognition between Incipient Species Is Linked to a Single Amino Acid Substitution in the Melanocortin?1 Receptor

    E-print Network

    Uy, J. Albert C.; Moyle, Robert G.; Filardi, Christopher E.; Cheviron, Zachary A.

    2009-08-01

    Many studies demonstrate that differences in mating signals are used by incipient species in recognizing potential mates or sexual competitors (i.e., species recognition). Little is known, however, about the genetic changes ...

  20. Nonvolitional sex and sexual health.

    PubMed

    Kalmuss, Debra

    2004-06-01

    Nonvolitional sex is sexual behavior that violates a person's right to choose when and with whom to have sex and what sexual behaviors to engage in. The more extreme forms of this behavior include rape, forced sex, childhood sexual abuse, sex trafficking, and violence against people with nonconventional sexual identities. More nuanced forms of nonvolitional sex include engaging in sexual behavior that masks one's nonconventional sexual identity, or that protects one's position with peers, or that represents a quid pro quo for the economic support that one obtains within an intimate relationship. The aim of this essay is to highlight the ways in which nonvolitional sex threatens sexual health and to identify strategies for ameliorating this problem. These strategies will have to be as broad in scope as is the problem that they are designed to address. The essay discusses the following strategies to reduce nonvolitional sex: (1) advocacy for sexual rights, gender equality, and equality for individuals with nonconventional sexual identities; (2) primary prevention programs and interventions that offer comprehensive sexuality education that establishes volitional sex and sexual health as basic human rights; (3) health services that routinely ask clients about their experiences with nonvolitional sex in an open and culturally appropriate manner; and (4) secondary prevention programs to meet the needs of victims of nonvolitional sex identified by the "screening" programs. PMID:15129039

  1. The wide phylogenetic and geographical patterns of sexual recombination indicate that it has intrinsic

    E-print Network

    Johnston, Mark

    recombining lineages have adapted to aeons of sexual reproduction, the transition to proficient, asexual not totally out- competed asexual, clonally reproducing lineages. In fact, asexual lineages are found among4­6 . Despite this, most asexual lineages of plants and animals are derived only recently from

  2. Sexual side effects of serotonergic antidepressants: mediated by inhibition of serotonin on central dopamine release?

    PubMed

    Bijlsma, Elisabeth Y; Chan, Johnny S W; Olivier, Berend; Veening, Jan G; Millan, Mark J; Waldinger, Marcel D; Oosting, Ronald S

    2014-06-01

    Antidepressant-induced sexual dysfunction adversely affects the quality of life of antidepressant users and reduces compliance with treatment. Animal models provide an instructive approach for examining potential sexual side effects of novel drugs. This review discusses the stability and reproducibility of our standardized test procedure that assesses the acute, subchronic and chronic effects of psychoactive compounds in a 30 minute mating test. In addition, we present an overview of the effects of several different (putative) antidepressants on male rat sexual behavior, as tested in our standardized test procedure. By comparing the effects of these mechanistically distinct antidepressants (paroxetine, venlafaxine, bupropion, buspirone, DOV 216,303 and S32006), this review discusses the putative mechanism underlying sexual side effects of antidepressants and their normalization. This review shows that sexual behavior is mainly inhibited by antidepressants that increase serotonin neurotransmission via blockade of serotonin transporters, while those that mainly increase the levels of dopamine and noradrenaline are devoid of sexual side effects. Those sexual disturbances cannot be normalized by simultaneously increasing noradrenaline neurotransmission, but are normalized by increasing both noradrenaline and dopamine neurotransmission. Therefore, it is hypothesized that the sexual side effects of selective serotonin reuptake inhibitors may be mediated by their inhibitory effects on dopamine signaling in sex brain circuits. Clinical development of novel antidepressants should therefore focus on compounds that simultaneously increase both serotonin and dopamine signaling. PMID:24128918

  3. Evolution of pathogenicity and sexual reproduction in eight Candida genomes

    E-print Network

    Kellis, Manolis

    ARTICLES Evolution of pathogenicity and sexual reproduction in eight Candida genomes Geraldine. Gow5 , Michael C. Lorenz21 , Bruce W. Birren3 , Manolis Kellis2,3 * & Christina A. Cuomo3 * Candida sequences of six Candida species and compare these and related pathogens and non

  4. Cryptic Sexuality Influences Aflatoxigenicity in Aspergillus parasiticus and A. flavus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ascomycetous fungi of the genus Aspergillus comprise a wide variety of species of biotechnological importance as well as pathogens and toxin producers. Recent studies report A. fumigatus to be heterothallic and possibly undergoing sexual reproduction. We therefore investigated whether compatible mat...

  5. Speciation in birds: Genes, geography, and sexual selection

    E-print Network

    Edwards, Scott

    Colloquium Speciation in birds: Genes, geography, and sexual selection Scott V. Edwards* , Sarah B molecular resolu- tion--to clone speciation genes if they exist--and thereby evaluate the relative roles not of logistically tractable species with easily sampled and manipulated populations; rather, this book focused

  6. Neuroanatomical dichotomy of sexual behaviors in rodents: a special emphasis on brain serotonin.

    PubMed

    Angoa-Pérez, Mariana; Kuhn, Donald M

    2015-09-01

    Much of the social behavior in which rodents engage is related to reproduction, such as maintaining a breeding territory, seeking mates, mating, and caring for their young. Rodents belong to the internally fertilizing species that require sexual behavior for reproduction. The dyadic, heterosexual patterns of most mammalian species are sexually dimorphic, but they also share mutual components in both sexes: sexual attraction is reciprocal, sexual initiative is assumed, appetitive behavior is engaged in, and mating involves consummatory and postconsummatory phases in females as well as in males. Serotonin, a phylogenetically ancient molecule, is the most widely distributed neurotransmitter in the brain and its signaling pathways are essential for numerous functions including sexual behavior. Since the late 1960s, brain serotonergic neurotransmission has been considered to exert an inhibitory influence on the neural mechanisms mediating sexual behavior. This contention was based mainly on the observations that a decrease in central serotonergic activity facilitated the elicitation of sexual behavior, whereas an increase in central serotonergic activity attenuated it. However, the discovery of over 14 types of serotonin receptors has added numerous layers of complexity to the study of serotonin and sexual behavior. Evidence shows that, upon activation, certain receptor subtypes facilitate, whereas some others suppress, sexual behavior, as well as sexual arousal and motivation. Furthermore, the role of these receptors has been shown to be different in the male and female sexes. The use of serotonergic pharmacological interventions, mouse strains with genetic polymorphisms causing alterations in the levels of brain serotonin, and animal models with genetic manipulations of various serotonin effectors has helped delineate the fundamental role of this neurotransmitter in the regulation of sexual behavior. This review aims to examine the basics of the components of female and male sexual behavior and the participation of the serotonin system in the modulation of these behaviors, with emphasis on rodents. PMID:26110223

  7. High-risk sexual offenders: an examination of sexual fantasy, sexual paraphilia, psychopathy, and offence characteristics.

    PubMed

    Woodworth, Michael; Freimuth, Tabatha; Hutton, Erin L; Carpenter, Tara; Agar, Ava D; Logan, Matt

    2013-01-01

    High-risk sexual offenders are a complex and heterogeneous group of offenders about whom researchers, clinicians, and law enforcement agencies still know relatively little. In response to the paucity of information that is specifically applicable to high-risk offenders, the present study investigated the potential influence of sexual fantasy, sexual paraphilia, and psychopathy on the offending behaviour of 139 of the highest risk sexual offenders in one province of Canada. The sample included 41 child molesters, 42 rapists, 18 rapist/molesters, 30 mixed offenders, and 6 "other" sexual offenders. Two offenders could not be categorized by type due to insufficient file information. Data analyses revealed significant differences between offender types for a number of criminal history variables including past sexual and nonsexual convictions, number of victims, weapon use, and age of offending onset. Further, there were significant differences between offender types for sexual fantasy themes, paraphilia diagnoses, and levels of psychopathy. For example, results revealed that offenders' sexual fantasies were significantly more likely to correspond with the specific type of index sexual offence that they had committed. Further, offenders scoring high in psychopathy were significantly more likely to have a sadistic paraphilia than offenders with either low or moderate psychopathy scores. Results from the current study provide a refined and informed understanding of sexual offending behaviour with important implications for future research, assessment, and treatment, as well as law enforcement practices when working with high-risk sexual offenders. PMID:23395507

  8. The R software environment in reproducible geoscientific research

    NASA Astrophysics Data System (ADS)

    Pebesma, Edzer; Nüst, Daniel; Bivand, Roger

    2012-04-01

    Reproducibility is an important aspect of scientific research, because the credibility of science is at stake when research is not reproducible. Like science, the development of good, reliable scientific software is a social process. A mature and growing community relies on the R software environment for carrying out geoscientific research. Here we describe why people use R and how it helps in communicating and reproducing research.

  9. Women's History of Sexual Abuse, Their Sexuality, and Sexual Self-Cindy M. Meston and Alessandra H. Rellini

    E-print Network

    Meston, Cindy

    , and Reproduction In this study, the authors assessed 48 female survivors of child sexual abuse (CSA) and 71 femaleWomen's History of Sexual Abuse, Their Sexuality, and Sexual Self- Schemas Cindy M. Meston control participants using measures of adult sexual function, psychological function (i.e., depression

  10. Sexual harassment consists of nonconsensual sexual advances, requests for sexual favors, or other verbal or physical conduct

    E-print Network

    Lee, Daeyeol

    /7) (Sexual Harassment and Assault Response & Education) Yale Health, Lower LevelSexual harassment consists of nonconsensual sexual advances, requests for sexual favors, or other verbal or physical conduct of a sexual nature on or off campus, when: (1) submission to such conduct

  11. Virtual Reference Environments: a simple way to make research reproducible

    PubMed Central

    Hurley, Daniel G.; Budden, David M.

    2015-01-01

    Reproducible research’ has received increasing attention over the past few years as bioinformatics and computational biology methodologies become more complex. Although reproducible research is progressing in several valuable ways, we suggest that recent increases in internet bandwidth and disk space, along with the availability of open-source and free-software licences for tools, enable another simple step to make research reproducible. In this article, we urge the creation of minimal virtual reference environments implementing all the tools necessary to reproduce a result, as a standard part of publication. We address potential problems with this approach, and show an example environment from our own work. PMID:25433467

  12. Sexual selection's impacts on ecological specialization: an experimental test.

    PubMed

    Pfennig, Karin S; Pfennig, David W; Porter, Cody; Martin, Ryan A

    2015-05-22

    In many species, individuals specialize on different resources, thereby reducing competition. Such ecological specialization can promote the evolution of alternative ecomorphs-distinct phenotypes adapted for particular resources. Elucidating whether and how this process is influenced by sexual selection is crucial for understanding how ecological specialization promotes the evolution of novel traits and, potentially, speciation between ecomorphs. We evaluated the population-level effects of sexual selection (as mediated by mate choice) on ecological specialization in spadefoot toad tadpoles that express alternative ecomorphs. We manipulated whether sexual selection was present or reversed by mating females to their preferred versus non-preferred males, respectively. We then exposed their tadpoles to resource competition in experimental mesocosms. The resulting distribution of ecomorphs was similar between treatments, but sexual selection generated poorer trait integration in, and lower fitness of, the more specialized carnivore morph. Moreover, disruptive and directional natural selection were weaker in the sexual selection present treatment. Nevertheless, this effect on disruptive selection was smaller than previously documented effects of ecological opportunity and competitor density. Thus, sexual selection can inhibit adaptation to resource competition and thereby hinder ecological specialization, particularly when females obtain fitness benefits from mate choice that offset the cost of producing competitively inferior offspring. PMID:25925102

  13. Positive allometry and the prehistory of sexual selection.

    PubMed

    Tomkins, Joseph L; LeBas, Natasha R; Witton, Mark P; Martill, David M; Humphries, Stuart

    2010-08-01

    The function of the exaggerated structures that adorn many fossil vertebrates remains largely unresolved. One recurrent hypothesis is that these elaborated traits had a role in thermoregulation. This orthodoxy persists despite the observation that traits exaggerated to the point of impracticality in extant organisms are almost invariably sexually selected. We use allometric scaling to investigate the role of sexual selection and thermoregulation in the evolution of exaggerated traits of the crested pterosaur Pteranodon longiceps and the sail-backed eupelycosaurs Dimetrodon and Edaphosaurus. The extraordinarily steep positive allometry of the head crest of Pteranodon rules out all of the current hypotheses for this trait's main function other than sexual signaling. We also find interspecific patterns of allometry and sexual dimorphism in the sails of Dimetrodon and patterns of elaboration in Edaphosaurus consistent with a sexually selected function. Furthermore, small ancestral, sail-backed pelycosaurs would have been too small to need adaptations to thermoregulation. Our results question the popular view that the elaborated structures of these fossil species evolved as thermoregulatory organs and provide evidence in support of the hypothesis that Pteranodon crests and eupelycosaur sails are among the earliest and most extreme examples of elaborate sexual signals in the evolution of terrestrial vertebrates. PMID:20565262

  14. Male brush-turkeys attempt sexual coercion in unusual circumstances.

    PubMed

    Wells, David A; Jones, Darryl N; Bulger, David; Brown, Culum

    2014-07-01

    Sexual coercion by males is generally understood to have three forms: forced copulation, harassment and intimidation. We studied Australian brush-turkeys, Alectura lathami, to determine whether some male behaviours towards females at incubation mounds could be classified as aggressive, whether males were attempting sexual coercion and, if so, whether the coercion was successful. We found that some male behaviours towards females were significantly more likely to be followed by the cessation of female mound activity, and hence could be classified as aggressive, while others were significantly more likely to be followed by the commencement of female mound activity, and hence could be classified as enticing. Copulation was preceded by higher rates of male enticement and by higher rates of certain types of male aggression. It therefore seemed that males were attempting sexual coercion. There was little evidence, however, that this combination of coercion and enticement was successful in obtaining copulations. While forced copulation did occur, it was infrequent, and no evidence could be found for intimidation. We conclude that harassment is the primary form of sexual coercion by male brush-turkeys. Although sexual coercion is understood to be a sub-optimal tactic, brush-turkey sexual coercion was employed as a primary tactic by dominant males who owned incubation mounds. One possible explanation for this apparent paradox is that aggression is the default solution for social conflicts in this species, and hence can be interpreted as a behavioural syndrome. PMID:24932897

  15. Ecological Sexual Dimorphism and Environmental Variability within a Community of Antarctic Penguins (Genus Pygoscelis)

    PubMed Central

    Gorman, Kristen B.; Williams, Tony D.; Fraser, William R.

    2014-01-01

    Background Sexual segregation in vertebrate foraging niche is often associated with sexual size dimorphism (SSD), i.e., ecological sexual dimorphism. Although foraging behavior of male and female seabirds can vary markedly, differences in isotopic (carbon, ?13C and nitrogen, ?15N) foraging niche are generally more pronounced within sexually dimorphic species and during phases when competition for food is greater. We examined ecological sexual dimorphism among sympatric nesting Pygoscelis penguins asking whether environmental variability is associated with differences in male and female pre-breeding foraging niche. We predicted that all Pygoscelis species would forage sex-specifically, and that higher quality winter habitat, i.e., higher or lower sea ice coverage for a given species, would be associated with a more similar foraging niche among the sexes. Results P2/P8 primers reliably amplified DNA of all species. On average, male Pygoscelis penguins are structurally larger than female conspecifics. However, chinstrap penguins were more sexually dimorphic in culmen and flipper features than Adélie and gentoo penguins. Adélies and gentoos were more sexually dimorphic in body mass than chinstraps. Only male and female chinstraps and gentoos occupied separate ?15N foraging niches. Strong year effects in ?15N signatures were documented for all three species, however, only for Adélies, did yearly variation in ?15N signatures tightly correlate with winter sea ice conditions. There was no evidence that variation in sex-specific foraging niche interacted with yearly winter habitat quality. Conclusion Chinstraps were most sexually size dimorphic followed by gentoos and Adélies. Pre-breeding sex-specific foraging niche was associated with overall SSD indices across species; male chinstrap and gentoo penguins were enriched in ?15N relative to females. Our results highlight previously unknown trophic pathways that link Pygoscelis penguins with variation in Southern Ocean sea ice suggesting that each sex within a species should respond similarly in pre-breeding trophic foraging to changes in future winter habitat. PMID:24599330

  16. Sexual assault in the workplace.

    PubMed

    Garrett, Linda H

    2011-01-01

    Women are sexually assaulted at an alarming rate, and the workplace is a frequent arena for assault. However, in recent decades, attention has been given to improving responses to sexual assault. Sexual assault is a frequent cause of injury and death for women in the United States. One in five American women admit they have experienced a completed rape during their lifetime. These estimates are conservative because sexual assault and sexual violence are both underreported and underprosecuted. Fear of job loss and discrimination are frequent reasons women do not report sexual assault in the workplace. Women are entering the workplace in greater numbers due in part to more single parent families and the depressed economy. Also, women are entering work environments that have traditionally been the domain of male workers: corporate headquarters, semi trucks, health care providers' offices, rural farms, and rural factories. Employers must have a plan to protect female employees and effectively address any incidents of sexual assault or violence. Occupational health nurses and nurse practitioners can assist both employees and employers to prevent sexual assault and resolve the aftermath of sexual assault. However, to accomplish this goal, occupational health nurses and nurse practitioners must be trained in sexual assault and violence response as well as preventive interventions. PMID:21175106

  17. Sexualization and lifestyle impulsivity: clinically valid discriminators in sexual offenders.

    PubMed

    Eher, Reinhard; Neuwirth, Wolfgang; Fruehwald, Stefan; Frottier, Patrick

    2003-08-01

    Following clinical observations in this study a comparison was undertaken between nonsexualized rapists, sexualized rapists, and pedophilic child molesters in terms of psychometric measures, criminological data, and DSM-IV diagnoses following the authors' hypotheses that nonsexualized and sexualized rapists differ in respect of psychiatric comorbidity and criminal history and sexualized rapists and pedophilic child molesters are more similar as regards to psychiatric comorbidity (anxiety, depression, and aggression) and criminal history variables than nonsexualized and sexualized rapists are. Preliminary findings confirmed the hypotheses: the authors found significant differences between paraphilic and sexualized sex offenders on one hand--regardless whether they had offended against minors or adults--and a group of sex offenders exhibiting a history of high lifestyle impulsivity on the other hand. From a psychiatric clinical point of view, paraphilic or sexualized rapists could be shown to resemble more the pedophilic child molesters. Therapeutic approaches should take these findings into account. PMID:12971185

  18. Sexual Assault: Victims, Emotional Effects, and Recovery.

    ERIC Educational Resources Information Center

    Marting, Glenda M.

    This paper on sexual assault defines the terms connected with sexual assault and identifies the most common situations in which sexual assault occurs. Information on the types of people who are sexual assault offenders is presented. Common myths concerning sexual assault, particularly rape, that are held in some segments of society are presented…

  19. Relationship Violence & Sexual Misconduct Policy: An Overview

    E-print Network

    violence, including rape and sexual assault of students retaliation against students who claim a violation harassment and such acts of sexual violence as rape, sexual assault, and sexual coercion. "Relationship person without that person's consent. "Rape" is defined as sexual penetration of another person without

  20. Sexuality in the brain.

    PubMed

    Doell, R G

    1995-01-01

    Research on the biological "causes" of homosexuality focuses primarily upon the hypothesis that hormonal influences during fetal life "organize" certain parts of the brain which thus become centers for sexual orientation and behavior later in life. This paper briefly summarizes criticisms of this research that demonstrate little evidence for the operation of such centers and emphasizes alternative scenarios for the development of sexual orientation and behavior which have been slighted by the biological and medical communities. Finally, I suggest that commitment to a belief in a biological mechanism which supports the hierarchy of power by those who benefit from that power maintains the viability of the hypothesis in the face of negative evidence. PMID:7560935

  1. Men sexually assaulted as adults and sexually abused as boys.

    PubMed

    Myers, M F

    1989-06-01

    Previous research on sexually victimized men has mainly addressed the acute symptoms seen in hospital emergency rooms and psychiatric clinics. Findings are reported on 14 men, all but 1 of whom had been sexually traumatized much earlier in life, as boys or young adults. Several problem areas are described: repression, denial, or normalization of the trauma; self-blame and shame; posttraumatic stress disorder; male gender identity fragility; sexual orientation ambiguity and internalized homophobia; sexual difficulties; mistrustfulness of adult men; and disturbances of self-esteem and body image. Gender issues in treatment are discussed. PMID:2751415

  2. Treatment of sexually compulsive adolescents.

    PubMed

    Gerber, James

    2008-12-01

    We clarified the nature of sexual compulsivity in adolescence, addressed who is labeled as "sexually compulsive youth," conceptualized the underlying factors of sexual compulsivity, and outlined a treatment format. We focused on trauma, dissociation, attachment, and self-concept. We questioned the conventional perceptions of who is included in this group. We reiterated that the belief that sexually compulsive adolescents are abusive males is no longer considered accurate. The evolution and accessibility of the Internet only raises greater concerns about compulsive sexual behavior, as more adolescents are brought into therapy because of Internet use to seek sexual interaction or stimulation. The sexually compulsive youth is as likely to be the clean-cut, high-achieving, intelligent student as is the economically deprived, juvenile delinquent on the street. This article began with the observation that adolescents rarely receive any direct, accurate information about sexuality and intimacy. The messages taken in through music, television, movies, politicians, popular press, clergy, and school are polarizing and contradictory. Beyond this are the implications as to how we, as a society, treat the youths that do present with sexual behavior problems. We have tended to treat these youth (as well as adults) with disdain and to designate sexually abusive youth the same as adult offenders with harsher, more punitive treatment interventions. Research and clinical experience now strongly question this type of response. This article is consistent with this leaning. Early psychological injury, from sexual abuse, physical abuse, exposure to violence, attachment trauma, or early sexualization, is at the root of sexually compulsive behavior. While it is necessary to reign in out-of-control and destructive behaviors, if we acknowledge that the source of the behavior is psychological injury, then it is cruel and inconsistent to treat the individual with disdain or as a pariah. The same dilemma is present with adult sexual addicts and offenders. Our society must develop a response to sexually compulsive or offensive behavior that can protect those who need protection, while implementing a rational legal response and providing treatment options for the underlying injury. Perhaps even more importantly, our society must learn how to educate adolescents about sexuality with clear, accurate information that includes not only reproduction but sexual response and intimacy as well. PMID:18996305

  3. Sexual Victimization among Spanish College Women and Risk Factors for Sexual Revictimization

    ERIC Educational Resources Information Center

    Santos-Iglesias, Pablo; Sierra, Juan Carlos

    2012-01-01

    Sexual revictimization is frequent among victims of child sexual abuse. Several variables, such as sexual experience, substance abuse, and sexual assertiveness, have been proposed to explain the link between child sexual abuse and adolescent and adult sexual victimization, although they have typically been tested separately. The main objective of…

  4. Barnard College Sexual Violence Resources Definitions of gender based or sexual misconduct

    E-print Network

    /her supervisor. Harassment because of one's sexual orientation also constitutes a violation of this policy or sexual orientation · Inappropriate sexual innuendoes or humor · Videotaping and photographing someoneBarnard College Sexual Violence Resources Definitions of gender based or sexual misconduct Sexual

  5. Handedness and sexual orientation.

    PubMed

    Holtzen, D W

    1994-10-01

    Surveys of handedness distribution (i.e., the distribution across handedness categories in large samples, typically based upon self-reported right-, mixed- and left-handed classification) indicate approximately 90% of the population is right-handed (Springer & Deutsch, 1989). This distribution toward right-handedness has been called right shift based on a genetic model (Annett, 1985). The present study examined possible handedness distribution differences between 141 gay, lesbian, and bisexuals and 260 heterosexuals who have a homosexual/bisexual first-degree (biological) relative. Based on a five-category self-assessment handedness questionnaire that was validated using Briggs and Nebes' (1975) reformulation of Annett's inventory (1970), non-heterosexuals showed a reduction of right shift compared to heterosexuals (i.e., a population shift toward mixed- and left-handedness), confirming the results of Lindesay (1987) and Becker et al., (1989). Sexual orientation also weakly predicted handedness. The findings indirectly support the hypothesis of Geschwind and Galaburda (1985a, 1985b) that sexual orientation and handedness may be linked, both possibly influenced prenatally by testosterone. The discussion emphasizes (a) the meaninglessness in distinguishing genetic from hormonal influences and (b) non-heterosexually biased assumptions about human sexuality. PMID:7836493

  6. Military sexual trauma.

    PubMed

    Wieland, Diane M; Haley, Jenna L; Bouder, Michelle

    2011-12-01

    Nurses' awareness of MST as a specific type of sexual assault within the military culture and sensitivity to the physical and psychological symptoms are important aspects of care. Nurses must treat the physical and emotional components of sexual assault in all settings; however, referral to the veterans administration programs and resources is key for the woman veteran to receive the specialized care developed by the healthcare system. Women veterans who have PTSD from MST and combat exposure are prone to depression, suicide and substance use/abuse. Nurses must not fear asking the woman if she is having suicidal thoughts or has a plan and intent to follow through with the plan. MST and PTSD may result in internalized anger, shame, self-blame, helplessness, hopelessness and powerlessness. Patient safety is of utmost importance. Assessing Patients for Sexual Violence, A Guide for Health Care Providers (2009) is a useful resource for nurses. The National Center for PTSD (2009) newsletter on the topic of MST includes a list of research studies. The work of Benedict (2007) and Corbett (2007) provide additional personal accounts of women soldiers who were in the Middle East conflicts. The nurse's referral to specialized services to treat MST and PTSD with evidence-based therapies is a crucial first step in the resiliency and well-being of these brave women who have served in all branches of the U.S. military. PMID:22359967

  7. [Adolescent sexuality in Peru].

    PubMed

    Loli, A; Aramburu, C; Paxman, J M

    1987-01-01

    22% of the population of Peru, or 4.25 million individuals, is between the ages of 11 and 19 years. A survey was performed on a sample of 6,000 adolescents living in Lima, Cajamarca, Huarez, and Supe. Surveys were performed in a variety of locations, including school classrooms, maternity wards, schools, and work places. The questionnaire was constructed based on a format that had been tested in Nigeria; questions dealt with socioeconomic background, sex behavior, contraceptive behavior, pregnancy history, and health practices and knowledge. 60% of the adolescents were women and 40% were men. 41% had had at least 1 sexual experience; among 18-year-olds, this % rose to 55. Only 10% were in stable union. Married adolescents tended to have begun sexual relations sooner in life. Early sexual relations were more common among men than among women, and more common among non-religious adolescents than among Catholics. Fewer than 12% of the adolescents had at 1 time used contraceptives. Contraceptive use was more prevalent among adolescents from wealthier socioeconomic groups, and more prevalent in Lima than in other regions surveyed. Of adolescents using contraceptives, 38% used condoms, 24% used oral contraceptives, and 15% used rhythm methods. Most adolescents who did not use contraceptives failed to do so because of lack of knowledge. Almost 1/4 of the young women had had a pregnancy. 18.5 of these had abortions, usually in a hospital. The importance of supporting educational prevention programs is underlined. PMID:12269059

  8. Greater Exposure to Sexual Content in Popular Movies Predicts Earlier Sexual Debut and Increased Sexual Risk Taking

    PubMed Central

    O’Hara, Ross E.; Gibbons, Frederick X.; Gerrard, Meg; Li, Zhigang; Sargent, James D.

    2013-01-01

    Early sexual debut is associated with risky sexual behavior and an increased risk of unplanned pregnancy and sexually transmitted infections later in life. The relations among early movie sexual exposure (MSE), sexual debut, and risky sexual behavior in adulthood (i.e., multiple sexual partners and inconsistent condom use) were examined in a longitudinal study of U.S. adolescents. MSE was measured using the Beach method, a comprehensive procedure for media content coding. Controlling for characteristics of adolescents and their families, analyses showed that MSE predicted age of sexual debut, both directly and indirectly through changes in sensation seeking. MSE also predicted engagement in risky sexual behaviors both directly and indirectly via early sexual debut. These results suggest that MSE may promote sexual risk taking both by modifying sexual behavior and by accelerating the normal rise in sensation seeking during adolescence. PMID:22810165

  9. Greater exposure to sexual content in popular movies predicts earlier sexual debut and increased sexual risk taking.

    PubMed

    O'Hara, Ross E; Gibbons, Frederick X; Gerrard, Meg; Li, Zhigang; Sargent, James D

    2012-09-01

    Early sexual debut is associated with risky sexual behavior and an increased risk of unplanned pregnancy and sexually transmitted infections later in life. The relations among early movie sexual exposure (MSE), sexual debut, and risky sexual behavior in adulthood (i.e., multiple sexual partners and inconsistent condom use) were examined in a longitudinal study of U.S. adolescents. MSE was measured using the Beach method, a comprehensive procedure for media content coding. Controlling for characteristics of adolescents and their families, analyses showed that MSE predicted age of sexual debut, both directly and indirectly through changes in sensation seeking. MSE also predicted engagement in risky sexual behaviors both directly and indirectly via early sexual debut. These results suggest that MSE may promote sexual risk taking both by modifying sexual behavior and by accelerating the normal rise in sensation seeking during adolescence. PMID:22810165

  10. Female sexual function and response.

    PubMed

    Arcos, Barbara

    2004-01-01

    Although female sexual dysfunction is a problem with low priority, it can have a profound impact on quality of life. In women, the cycle of sexual response begins in the brain, where a memory, an image, a scent, music, or a fantasy acts as a trigger to prompt sexual arousal. Thus, the brain is really the key and starting place for treatment of sexual dysfunction. Decreased libido, altered arousal, inability to achieve orgasm, and dyspareunia are the four broad types of sexual dysfunction in women. Decreased libido, thought to be related to androgenic hormones, results in delayed or altered arousal, decreased vaginal lubrication and dilation, delayed or absent orgasm, and pain or dyspareunia, which can lead to an aversion to sexual experiences. PMID:14992322

  11. Sexual victimization, alcohol intoxication, sexual-emotional responding, and sexual risk in heavy episodic drinking women.

    PubMed

    George, William H; Davis, Kelly Cue; Masters, N Tatiana; Jacques-Tiura, Angela J; Heiman, Julia R; Norris, Jeanette; Gilmore, Amanda K; Nguyen, Hong V; Kajumulo, Kelly F; Otto, Jacqueline M; Andrasik, Michele P

    2014-05-01

    This study used an experimental paradigm to investigate the roles of sexual victimization history and alcohol intoxication in young women's sexual-emotional responding and sexual risk taking. A nonclinical community sample of 436 young women, with both an instance of heavy episodic drinking and some HIV/STI risk exposure in the past year, completed childhood sexual abuse (CSA) and adolescent/adult sexual assault (ASA) measures. A majority of them reported CSA and/or ASA, including rape and attempted rape. After random assignment to a high alcohol dose (.10 %) or control condition, participants read and projected themselves into an eroticized scenario of a sexual encounter involving a new partner. As the story protagonist, each participant rated her positive mood and her sexual arousal, sensation, and desire, and then indicated her likelihood of engaging in unprotected sex. Structural equation modeling analyses revealed that ASA and alcohol were directly associated with heightened risk taking, and alcohol's effects were partially mediated by positive mood and sexual desire. ASA was associated with attenuated sexual-emotional responding and resulted in diminished risk taking via this suppression. These are the first findings indicating that, compared to non-victimized counterparts, sexually victimized women respond differently in alcohol-involved sexual encounters in terms of sexual-emotional responding and risk-taking intentions. Implications include assessing victimization history and drinking among women seeking treatment for either concern, particularly women at risk for HIV, and alerting them to ways their histories and behavior may combine to exacerbate their sexual risks. PMID:23857517

  12. An Open Science and Reproducible Research Primer for Landscape Ecologists

    EPA Science Inventory

    In recent years many funding agencies, some publishers, and even the United States government have enacted policies that encourage open science and strive for reproducibility; however, the knowledge and skills to implement open science and enable reproducible research are not yet...

  13. 46 CFR 56.30-3 - Piping joints (reproduces 110).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56.30-3... APPURTENANCES Selection and Limitations of Piping Joints § 56.30-3 Piping joints (reproduces 110). The type of piping joint used shall be suitable for the design conditions and shall be selected with consideration...

  14. 46 CFR 56.30-3 - Piping joints (reproduces 110).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56.30-3... APPURTENANCES Selection and Limitations of Piping Joints § 56.30-3 Piping joints (reproduces 110). The type of piping joint used shall be suitable for the design conditions and shall be selected with consideration...

  15. 46 CFR 56.30-3 - Piping joints (reproduces 110).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56.30-3... APPURTENANCES Selection and Limitations of Piping Joints § 56.30-3 Piping joints (reproduces 110). The type of piping joint used shall be suitable for the design conditions and shall be selected with consideration...

  16. 46 CFR 56.30-3 - Piping joints (reproduces 110).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56.30-3... APPURTENANCES Selection and Limitations of Piping Joints § 56.30-3 Piping joints (reproduces 110). The type of piping joint used shall be suitable for the design conditions and shall be selected with consideration...

  17. Reproducibility of Apparent Diffusion Coefficient Measurements in Malignant Breast Masses

    PubMed Central

    Jang, Mijung; Yun, Bo La; Ahn, Hye Shin; Kim, Soo Yeon; Kang, Eunyoung; Kim, Sung-Won

    2015-01-01

    This study aimed to evaluate the reproducibility of apparent diffusion coefficient (ADC) measurements in malignant breast masses, and to determine the influence of mammographic parenchymal density on this reproducibility. Sixty-six patients with magnetic resonance findings of the mass were included. Two breast radiologists measured the ADC of the malignant breast mass and the same area on the contralateral normal breast in each patient twice. The effects of mammographic parenchymal density, histology, and lesion size on reproducibility were also assessed. There was no significant difference in the mean ADC between repeated measurements in malignant breast masses and normal breast tissue. The overall reproducibility of ADC measurements was good in both. The 95% limits of agreement for repeated ADCs were approximately 30.2%-33.4% of the mean. ADC measurements in malignant breast masses were highly reproducible irrespective of mass size, histologic subtype, or coexistence of microcalcifications; however, the measurements tended to be less reproducible in malignant breast masses with extremely dense parenchymal backgrounds. ADC measurements in malignant breast masses are highly reproducible; however, mammographic parenchymal density can potentially influence this reproducibility. PMID:26539016

  18. 44 CONTRIBUTED RESEARCH ARTICLES Online Reproducible Research: An

    E-print Network

    Thioulouse, Jean

    - search articles. Rather than do this we decided to set up a simple computer environment using R to offer44 CONTRIBUTED RESEARCH ARTICLES Online Reproducible Research: An Application to Multivariate Abstract This paper presents an example of online reproducible multivariate data analysis. This example

  19. Environmental origins of sexually selected variation and a critique of the fluctuating asymmetry-sexual selection hypothesis.

    PubMed

    Polak, Michal; Starmer, William T

    2005-03-01

    Identifying sources of phenotypic variability in secondary sexual traits is critical for understanding their signaling properties, role in sexual selection, and for predicting their evolutionary dynamics. The present study tests for the effects of genotype, developmental temperature, and their interaction, on size and fluctuating asymmetry of the male sex comb, a secondary sexual character, in Drosophila bipectinata Duda. Both the size and symmetry of elements of the sex comb have been shown previously to be under sexual selection in a natural population in northeastern Australia. Two independent reciprocal crosses were conducted at 25 degrees and 29 degrees C between genetic lines extracted from this population that differed in the size of the first (TC1) and third (TC3) comb segments. These temperatures are within the documented range experienced by the species in nature. Additive and dominance genetic effects were detected for TC1, whereas additive genetic, and Y-chromosomal effects were detected for TC3. TC2 and TC3 decreased sharply with increasing temperature, by 10% and 22%, respectively. In contrast, positional fluctuating asymmetry (PFA) significantly increased with temperature, by up to 38%. The results (1) document an important source of environmental variance in a sexual ornament expected to reduce trait heritability in field populations, and thus act to attenuate response to sexual selection, (2) suggest that variation in ornament size reflects differences in male condition; and (3) support the general hypothesis that asymmetry in a sexual ornament is indicative of developmental instability arising from environmental stress. The "environmental heterogeneity" (EH) hypothesis is proposed, and supportive evidence for it presented, to explain negative size-FA correlations in natural populations. Data and theory challenge the use of negative size-FA correlations observed in nature to support the FA-sexual selection hypothesis, which posits that such correlations are driven by differences in genetic quality among individuals. PMID:15856700

  20. Girlfight and Bend it Like Beckham: screening women, sport, and sexuality.

    PubMed

    Caudwell, Jayne

    2009-01-01

    In this article, sport film is taken as a social and cultural space where women's bodies are made publicly in/visible. Two films-Girlfight and Bend it Like Beckham-provide the focus for critical discussion. Moreover, a queer-feminist analysis explores the links between participation in boxing and football, and women's sexuality as represented in the films. Lesbian sexualities are considered in a critique of the erasure of the lesbian sport [film] star. Sexual subjectivity is also discussed in relation to the heterosexual heroic and to patriarchy. In this way I interrogate heterosexuality. I also consider links between ethnicity, women's bodies, and sexuality. In the final instance, I show that the films work to reproduce heterosexual hegemony and depict heteronormative assimilation. PMID:19598047

  1. Mental illness and sexual offending.

    PubMed

    Booth, Brad D; Gulati, Sanjiv

    2014-06-01

    Transinstitutionalization (ie, the criminalization of those with mental illness) is relevant to individuals committing sexual offenses. Mental illness can affect the treatment and risk management of individuals committing sexual offenses. In this article the current literature on mentally disordered sexual offenders is described, including how psychosis, mood disorders, anxiety disorders, attention-deficit/hyperactivity disorder, and dementing disorders may affect treatment and management. PMID:24877705

  2. Sexual conflict and speciation.

    PubMed Central

    Parker, G A; Partridge, L

    1998-01-01

    We review the significance of two forms of sexual conflict (different evolutionary interests of the two sexes) for genetic differentiation of populations and the evolution of reproductive isolation. Conflicting selection on the alleles at a single locus can occur in males and females if the sexes have different optima for a trait, and there are pleiotropic genetic correlations between the sexes for it. There will then be selection for sex limitation and hence sexual dimorphism. This sex limitation could break down in hybrids and reduce their fitness. Pleiotropic genetic correlations between the sexes could also affect the likelihood of mating in interpopulation encounters. Conflict can also occur between (sex-limited) loci that determine behaviour in males and those that determine behaviour in females. Reproductive isolation may occur by rapid coevolution of male trait and female mating preference. This would tend to generate assortative mating on secondary contact, hence promoting speciation. Sexual conflict resulting from sensory exploitation, polyspermy and the cost of mating could result in high levels of interpopulation mating. If females evolve resistance to make pre- and postmating manipulation, males from one population could be more successful with females from the other, because females would have evolved resistance to their own (but not to the allopatric) males. Between-locus sexual conflict could also occur as a result of conflict between males and females of different populations over the production of unfit hybrids. We develop models which show that females are in general selected to resist such matings and males to persist, and this could have a bearing on both the initial level of interpopulation matings and the likelihood that reinforcement will occur. In effect, selection on males usually acts to promote gene flow and to restrict premating isolation, whereas selection on females usually acts in the reverse direction. We review theoretical models relevant to resolution of this conflict. The winning role depends on a balance between the 'value of winning' and 'power' (relating to contest or armament costs): the winning role is likely to correlate with high value of winning and low costs. Sperm-ovum (or sperm-female tract) conflicts (and their plant parallels) are likely to obey the same principles. Males may typically have higher values of winning, but it is difficult to quantify 'power', and females may often be able to resist mating more cheaply than males can force it. We tentatively predict that sexual conflict will typically result in a higher rate of speciation in 'female-win' clades, that females will be responsible for premating isolation through reinforcement, and that 'female-win' populations will be less genetically diverse. PMID:9533125

  3. Colour mimicry and sexual deception by Tongue orchids ( Cryptostylis)

    NASA Astrophysics Data System (ADS)

    Gaskett, A. C.; Herberstein, M. E.

    2010-01-01

    Typically, floral colour attracts pollinators by advertising rewards such as nectar, but how does colour function when pollinators are deceived, unrewarded, and may even suffer fitness costs? Sexually deceptive orchids are pollinated only by male insects fooled into mating with orchid flowers and inadvertently transferring orchid pollinia. Over long distances, sexually deceptive orchids lure pollinators with counterfeit insect sex pheromones, but close-range deception with colour mimicry is a tantalising possibility. Here, for the first time, we analyse the colours of four sexually deceptive Cryptostylis orchid species and the female wasp they mimic ( Lissopimpla excelsa, Ichneumonidae), from the perspective of the orchids’ single, shared pollinator, male Lissopimpla excelsa. Despite appearing different to humans, the colours of the orchids and female wasps were effectively identical when mapped into a hymenopteran hexagonal colour space. The orchids and wasps reflected predominantly red-orange wavelengths, but UV was also reflected by raised bumps on two orchid species and by female wasp wings. The orchids’ bright yellow pollinia contrasted significantly with their overall red colour. Orchid deception may therefore involve accurate and species-specific mimicry of wavelengths reflected by female wasps, and potentially, exploitation of insects’ innate attraction to UV and yellow wavelengths. In general, mimicry may be facilitated by exploiting visual vulnerabilities and evolve more readily at the peripheries of sensory perception. Many sexually deceptive orchids are predominantly red, green or white: colours that are all potentially difficult for hymenoptera to detect or distinguish from the background.

  4. Convergent evolution of a fused sexual cycle promotes the haploid lifestyle

    NASA Astrophysics Data System (ADS)

    Sherwood, Racquel Kim; Scaduto, Christine M.; Torres, Sandra E.; Bennett, Richard J.

    2014-02-01

    Sexual reproduction is restricted to eukaryotic species and involves the fusion of haploid gametes to form a diploid cell that subsequently undergoes meiosis to generate recombinant haploid forms. This process has been extensively studied in the unicellular yeast Saccharomyces cerevisiae, which exhibits separate regulatory control over mating and meiosis. Here we address the mechanism of sexual reproduction in the related hemiascomycete species Candida lusitaniae. We demonstrate that, in contrast to S. cerevisiae, C. lusitaniae exhibits a highly integrated sexual program in which the programs regulating mating and meiosis have fused. Profiling of the C. lusitaniae sexual cycle revealed that gene expression patterns during mating and meiosis were overlapping, indicative of co-regulation. This was particularly evident for genes involved in pheromone MAPK signalling, which were highly induced throughout the sexual cycle of C. lusitaniae. Furthermore, genetic analysis showed that the orthologue of IME2, a `diploid-specific' factor in S. cerevisiae, and STE12, the master regulator of S. cerevisiae mating, were each required for progression through both mating and meiosis in C. lusitaniae. Together, our results establish that sexual reproduction has undergone significant rewiring between S. cerevisiae and C. lusitaniae, and that a concerted sexual cycle operates in C. lusitaniae that is more reminiscent of the distantly related ascomycete, Schizosaccharomyces pombe. We discuss these results in light of the evolution of sexual reproduction in yeast, and propose that regulatory coupling of mating and meiosis has evolved multiple times as an adaptation to promote the haploid lifestyle.

  5. The geography of sex-specific selection, local adaptation, and sexual dimorphism.

    PubMed

    Connallon, Tim

    2015-09-01

    Local adaptation and sexual dimorphism are iconic evolutionary scenarios of intraspecific adaptive differentiation in the face of gene flow. Although theory has traditionally considered local adaptation and sexual dimorphism as conceptually distinct processes, emerging data suggest that they often act concurrently during evolutionary diversification. Here, I merge theories of local adaptation in space and sex-specific adaptation over time, and show that their confluence yields several new predictions about the roles of context-specific selection, migration, and genetic correlations, in adaptive diversification. I specifically revisit two influential predictions from classical studies of clinal adaptation and sexual dimorphism: (1) that local adaptation should decrease with distance from the species' range center and (2) that opposing directional selection between the sexes (sexual antagonism) should inevitably accompany the evolution of sexual dimorphism. I show that both predictions can break down under clinally varying selection. First, the geography of local adaptation can be sexually dimorphic, with locations of relatively high local adaptation differing profoundly between the sexes. Second, the intensity of sexual antagonism varies across the species' range, with subpopulations near the range center representing hotspots for antagonistic selection. The results highlight the context-dependent roles of migration versus sexual conflict as primary constraints to adaptive diversification. PMID:26194274

  6. Male sexual dysfunction in Asia

    PubMed Central

    Ho, Christopher CK; Singam, Praveen; Hong, Goh Eng; Zainuddin, Zulkifli Md

    2011-01-01

    Sex has always been a taboo subject in Asian society. However, over the past few years, awareness in the field of men's sexual health has improved, and interest in sexual health research has recently increased. The epidemiology and prevalence of erectile dysfunction, hypogonadism and premature ejaculation in Asia are similar in the West. However, several issues are specific to Asian males, including culture and beliefs, awareness, compliance and the availability of traditional/complementary medicine. In Asia, sexual medicine is still in its infancy, and a concerted effort from the government, relevant societies, physicians and the media is required to propel sexual medicine to the forefront of health care. PMID:21643001

  7. Assessing Youth Who Sexually Offended

    PubMed Central

    Ng, Kynaston; Fong, June; Teoh, Jennifer

    2012-01-01

    Recent research suggested that the predictive validity of adult sexual offender risk assessment measures can be affected when used cross-culturally, but there is no published study on the predictive validity of risk assessment measures for youth who sexually offended in a non-Western context. This study compared the predictive validity of three youth risk assessment measures (i.e., the Estimate of Risk of Adolescent Sexual Offense Recidivism [ERASOR], the Juvenile Sex Offender Assessment Protocol-II [J-SOAP-II], and the Youth Level of Service/Case Management Inventory [YLS/CMI]) for sexual and nonviolent recidivism in a sample of 104 male youth who sexually offended within a Singaporean context (Mfollow-up = 1,637 days; SD follow-up = 491). Results showed that the ERASOR overall clinical rating and total score significantly predicted sexual recidivism but only the former significantly predicted time to sexual reoffense. All of the measures (i.e., the ERASOR overall clinical rating and total score, the J-SOAP-II total score, as well as the YLS/CMI) significantly predicted nonsexual recidivism and time to nonsexual reoffense for this sample of youth who sexually offended. Overall, the results suggest that the ERASOR appears to be suited for assessing youth who sexually offended in a non-Western context, but the J-SOAP-II and the YLS/CMI have limited utility for such a purpose. PMID:21825111

  8. Exposure to Sexual Lyrics and Sexual Experience Among Urban Adolescents

    PubMed Central

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

    2010-01-01

    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

  9. Geographic variation in female mate-copying in the species complex of a unisexual fish, Poecilia formosa

    E-print Network

    Ryan, Michael J.

    these increase their attractiveness to the conspecific sexual females. In mixed shoals, mate-copying potentially matings with males of closely related sexual species. In mixed popu- lations, males mate with conspecific sexual females and heterospecific asexual females. Such matings are not isolated dyadic interactions

  10. Implicit cognitive distortions and sexual offending.

    PubMed

    Mihailides, Stephen; Devilly, Grant J; Ward, Tony

    2004-10-01

    This work develops and tests the semantic-motivation hypothesis of sexual offenders' implicit cognitions. This hypothesis posits that sexual offenders' cognitive distortions emerge at the interface between implicit motivation and cognition. The semantic-motivation hypothesis is used to guide the development of 3 implicit association tests (IATs). These IATs were used to test for the existence of 3 expected child sexual offender implicit cognitive distortions in child sexual offenders ("children as sexual beings," "uncontrollability of sexuality," and "sexual entitlement-bias"). Results showed that child sexual offenders had larger IAT effects than did mainstream offenders and male and female nonoffenders for the "children as sexual beings" and the "uncontrollability of sexuality" implicit theories. Child sexual offenders also had a larger IAT effect than male and female nonoffenders for the "sexual entitlement-bias" implicit theory. Implications for the semantic-motivation hypothesis are discussed. PMID:15560415

  11. Sexuality and Aging: An Overview for Counselors.

    ERIC Educational Resources Information Center

    Capuzzi, Dave

    1982-01-01

    Discusses male and female sexual response in aging adults. Describes common medical problems and their relationship to sexuality in older adults. Considers common surgeries including hysterectomy, mastectomy, and prostatectomy and sexuality in older adults. Discusses implications for counselors. (RC)

  12. Sexuality for the Woman with Cancer

    MedlinePLUS

    ... Topic How the female body works sexually Cancer, sex, and sexuality When you first learned you had ... affect your sexual function. What is a normal sex life? People vary a great deal in their ...

  13. A sexually conditioned switch of chemosensory behavior in C. elegans.

    PubMed

    Sakai, Naoko; Iwata, Ryo; Yokoi, Saori; Butcher, Rebecca A; Clardy, Jon; Tomioka, Masahiro; Iino, Yuichi

    2013-01-01

    In sexually reproducing animals, mating is essential for transmitting genetic information to the next generation and therefore animals have evolved mechanisms for optimizing the chance of successful mate location. In the soil nematode C. elegans, males approach hermaphrodites via the ascaroside pheromones, recognize hermaphrodites when their tails contact the hermaphrodites' body, and eventually mate with them. These processes are mediated by sensory signals specialized for sexual communication, but other mechanisms may also be used to optimize mate location. Here we describe associative learning whereby males use sodium chloride as a cue for hermaphrodite location. Both males and hermaphrodites normally avoid sodium chloride after associative conditioning with salt and starvation. However, we found that males become attracted to sodium chloride after conditioning with salt and starvation if hermaphrodites are present during conditioning. For this conditioning, which we call sexual conditioning, hermaphrodites are detected by males through pheromonal signaling and additional cue(s). Sex transformation experiments suggest that neuronal sex of males is essential for sexual conditioning. Altogether, these results suggest that C. elegans males integrate environmental, internal and social signals to determine the optimal strategy for mate location. PMID:23861933

  14. Social and Sexual Behaivours of Mice in Partial Gravity

    NASA Astrophysics Data System (ADS)

    Aou, Shuji; Hasegawa, Katsuya; Kumei, Yasuhiro; Inoue, Katarzyna; Zeredo, Jorge; Narikiyo, Kimiya; Watanabe, Yuuki

    2012-07-01

    We examined social and sexual behaviours in normal ICR mice, C57BL mice and obese db/db mice lacking leptin receptors in low gravity conditions using parabolic-flight to generate graded levels of partial gravity. Although both normal and obese mice floated with vigorous limb and tail movements when a floor is smooth in microgravity but they were rather stable if a floor is cover by carpet. Obese mice were more stable and socially contacted longer with a partner in low-gravity conditions. When they returned to the home cage after parabolic flights, obese mice started to eat sooner without restless behaviour, while control mice showed restless behaviour without eating. Face grooming, an indicator of stress response, was found more often in the control mice than the obese mice. Obese mice returned to resting condition faster than the control. We also analysed sexual behaviour of ICR mice and C57BL mice but not db/db mice since they are sexually inactive. Social and sexual behaviour could be evaluated in partial gravity conditions to get basic data concerning whether rodents can communicate and reproduce in Moon, Mars and space or not. Supported by Grant-in-Aid for Exploratory Research (JSPS) to S Aou and FY2010 grants from JAXA and Japan Society for Promotion of Science to Y. Kumei.

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

    PubMed

    Bancroft, John; Vukadinovic, Zoran

    2004-08-01

    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 were 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 addict group. Dissociative experiences were described by 45% of sex addicts and may have some explanatory relevance. Obsessive-compulsive mechanisms may be relevant in some cases, and the addiction concept may prove to be relevant with further research. Overall, results suggested that out of control sexual behavior results from a variety of mechanisms. We propose an alternative theoretical approach to investigating these mechanisms based on the dual control model and recent research on the relation between mood and sexuality. PMID:15497051

  16. Regulation of Male Sexual Behavior by Progesterone Receptor, Sexual

    E-print Network

    Crews, David

    . This model system allowed us to investigate the contributions PR makes to the sex behavior of malesRegulation of Male Sexual Behavior by Progesterone Receptor, Sexual Experience, and Androgen Steven M. Phelps,* John P. Lydon, Bert W. O'Malley, and David Crews*,1 *Institute of Reproductive Biology

  17. The Transmissibility of Sexually Transmitted Diseases in Sexually Abused Children.

    ERIC Educational Resources Information Center

    Hammerschlag, Margaret R.

    1998-01-01

    This paper summarizes what is known about, and research needs on, the transmissibility to sexually abused children of the following sexually transmitted diseases: gonorrhea, chlamydia trachomatis, human papillomavirus genital warts, condylomata acuminata, syphilis, bacterial vaginosis, trichomonas vaginalis, herpes simplex, and human…

  18. Contact sexual offending by men with online sexual offenses.

    PubMed

    Seto, Michael C; Hanson, R Karl; Babchishin, Kelly M

    2011-03-01

    There is much concern about the likelihood that online sexual offenders (particularly online child pornography offenders) have either committed or will commit offline sexual offenses involving contact with a victim. This study addresses this question in two meta-analyses: the first examined the contact sexual offense histories of online offenders, whereas the second examined the recidivism rates from follow-up studies of online offenders. The first meta-analysis found that approximately 1 in 8 online offenders (12%) have an officially known contact sexual offense history at the time of their index offense (k = 21, N = 4,464). Approximately one in two (55%) online offenders admitted to a contact sexual offense in the six studies that had self-report data (N = 523). The second meta-analysis revealed that 4.6% of online offenders committed a new sexual offense of some kind during a 1.5- to 6-year follow-up (k = 9, N = 2,630); 2.0% committed a contact sexual offense and 3.4% committed a new child pornography offense. The results of these two quantitative reviews suggest that there may be a distinct subgroup of online-only offenders who pose relatively low risk of committing contact sexual offenses in the future. PMID:21173158

  19. Social and Sexual Risk Factors among Sexual Minority Youth

    ERIC Educational Resources Information Center

    Quinn, Katherine; Ertl, Allison

    2015-01-01

    This study explores the characteristics and risk behaviors of sexual minority high school students using the 2011 Wisconsin Youth Risk Behavior Survey. Among 3,043 students surveyed, 8% of students identified as lesbian, gay, bisexual, or unsure, and 7% reported having contact with same-sex partners. Findings indicate sexual minority students…

  20. Sexual Learning, Sexual Experience, and Healthy Adolescent Sex

    ERIC Educational Resources Information Center

    Fortenberry, J. Dennis

    2014-01-01

    This chapter is organized around the question "How do adolescents learn to have healthy sex?" The chapter assumes that sexual learning derives from a broad range of both informal and formal sources that contribute to learning within the context of neurocognitive brain systems that modulate sexual motivations and self-regulation. The…

  1. Sexual medicine in family practice. Part 2: Treating sexual dysfunction.

    PubMed Central

    Holzapfel, S.

    1993-01-01

    Sexual problems can be caused by organic or psychological factors, or a combination of the two. Deciding which leads to an appropriate management plan. This paper describes the current status of treatments for common sexual dysfunctions seen in family practice. PMID:8471907

  2. Adolescent Sexuality: Pregnancy, Sexually Transmitted Diseases, and Prevention.

    ERIC Educational Resources Information Center

    Santelli, John S.; And Others

    1992-01-01

    Special edition discusses adolescent sexuality, focusing on pregnancy, sexually transmitted diseases, and prevention. The articles focus on demographics, risk factors, school-based risk reduction programs, contraception, early intervention, options, school-based prenatal and postpartum care programs, teenage parenting, abortion, HIV and AIDS,…

  3. Psychopathology and Deviant Sexual Arousal in Incarcerated Sexual Offenders.

    ERIC Educational Resources Information Center

    Serin, Ralph C.; And Others

    1994-01-01

    Investigates the relationship between psychopathology and deviant sexual arousal in sexual offenders (n=65), with approximately equal numbers of rapists and child molesters. Differentiating between rapists, extrafamilial pedophiles, and incest offenders revealed that the relationship between psychopathology and arousal was most apparent for…

  4. Constructing Sexual Identities: People with Intellectual Disability Talking about Sexuality

    ERIC Educational Resources Information Center

    Azzopardi-Lane, Claire; Callus, Anne-Marie

    2015-01-01

    This paper presented research undertaken in collaboration with a self-advocacy group using inclusive research methods and puts forward the views of people with intellectual disability on the topics of sexuality and relationships. The paper presents the perceptions of sexuality of the people with intellectual disability and how these are influenced…

  5. Reproductive mode and ovarian morphology regulation in chimeric planarians composed of asexual and sexual neoblasts.

    PubMed

    Nodono, Hanae; Matsumoto, Midori

    2012-07-01

    Planarians are comprised of populations with different reproductive strategies: exclusively innately asexual (AS), exclusively innately sexual (InS), and seasonally switching. AS worms can be sexualized experimentally by feeding them with minced InS worms, and the resultant worms are characterized as acquired sexual (AqS). Differences between InS and AqS worms are expected to provide important clues to the poorly understood mechanism underlying the regulation of their reproductive mode. Morphological differences were found between InS and AqS worm ovaries, and we showed that the pluripotent stem cells (neoblasts) from InS worms, but not those of AqS worms, have the capacity to initiate the sexual state autonomously via neoblast fraction transplantation. To compare their reproductive mode and ovarian morphology regulation, InS donor neoblast fractions were transplanted into non-lethally X-ray-irradiated AS recipients. All transplants showed stable chimerism and reproduced sexually, suggesting that InS worm neoblasts can initiate sexual state autonomously, even when coexisting with AS worm neoblasts. The chimeras formed extraordinarily large and supernumerary ovaries equivalent to AqS worms, which were not seen in InS worms, suggesting that regulation of ovarian morphology in AS worm-derived cells in response to endogenous sexualizing stimulation distinctly differs from that of InS worms. PMID:22565827

  6. SEXUAL MATURATION AND SPAWNING OF ATLANTIC MENHADEN By JOSEPH R. HIGHAM AND WILLIAM R. NICHOLSON, Fishery Biologists

    E-print Network

    SEXUAL MATURATION AND SPAWNING OF ATLANTIC MENHADEN By JOSEPH R. HIGHAM AND WILLIAM R. NICHOLSON, maturing and ripe. Two groups, each in a different stage of maturation, simultaneously developed of variations in the distribution, availability, and abundance of this species. Sexual maturation and spnwning

  7. Contrasting sexual selection on males and females in a role-reversed swarming dance fly, Rhamphomyia longicauda

    E-print Network

    Gwynne, Darryl T.

    ornaments (Fitzpatrick et al., 1995; Berglund et al., 1997). Given the potential trade-off between offspring, NSW, Australia Introduction Even though male sexual ornaments are well docu- mented in many species there is significant interest in showing that sexually selected male ornaments indicate heritable genetic quality

  8. Precocious sexual signalling and mating in Anastrepha fraterculus (Diptera: Tephritidae) sterile males achieved through juvenile hormone treatment and protein supplements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sexual maturation of Anastrepha fraterculus is a long process. Methoprene (a mimic of juvenile hormone) considerably reduces the time for sexual maturation in males. However, in other Anastrepha species, this effect depends on protein intake at the adult stage. Here, we evaluated the mating competit...

  9. The Porphyra species of Helgoland (Bangiales, Rhodophyta)

    NASA Astrophysics Data System (ADS)

    Kornmann, P.; Sahling, P.-H.

    1991-03-01

    This revision of seven Porphyra species of Helgoland was based on a study of the structure of their fertile thalli and the behaviour of their spores. Regarding the reproductive organization the species may be arranged in two groups. P. leucosticta and P. purpureo-violacea are obligate monoecious species. Asexual thalli have never been observed in the field. The other five species are generally dioecious. Isomorphic sexual thalli and asexually propagating ones are mixed in uniform populations. Carpospores originating from sexual fusion develop into the diploid Conchocelis phase. Sporangia of asexual plants, though homologous in formation, produce spores of different kinds: aplanospores that give rise to the vegetative thallus directly (in P. umbilicalis, P. insolita n. sp. and P. ochotensis) and spores that develop into haploid Conchocelis (in P. laciniata and in P. linearis). P. laciniata — formerly considered synonymous with P. purpurea — is an independent species.

  10. Effect of Initial Conditions on Reproducibility of Scientific Research

    PubMed Central

    Djulbegovic, Benjamin; Hozo, Iztok

    2014-01-01

    Background: It is estimated that about half of currently published research cannot be reproduced. Many reasons have been offered as explanations for failure to reproduce scientific research findings- from fraud to the issues related to design, conduct, analysis, or publishing scientific research. We also postulate a sensitive dependency on initial conditions by which small changes can result in the large differences in the research findings when attempted to be reproduced at later times. Methods: We employed a simple logistic regression equation to model the effect of covariates on the initial study findings. We then fed the input from the logistic equation into a logistic map function to model stability of the results in repeated experiments over time. We illustrate the approach by modeling effects of different factors on the choice of correct treatment. Results: We found that reproducibility of the study findings depended both on the initial values of all independent variables and the rate of change in the baseline conditions, the latter being more important. When the changes in the baseline conditions vary by about 3.5 to about 4 in between experiments, no research findings could be reproduced. However, when the rate of change between the experiments is ?2.5 the results become highly predictable between the experiments. Conclusions: Many results cannot be reproduced because of the changes in the initial conditions between the experiments. Better control of the baseline conditions in-between the experiments may help improve reproducibility of scientific findings. PMID:25132705

  11. Sexual discordance and sexual partnering among heterosexual women.

    PubMed

    Nield, Jennifer; Magnusson, Brianna; Brooks, Christopher; Chapman, Derek; Lapane, Kate L

    2015-05-01

    This study examined characteristics of self-identified heterosexual women who were concordant or discordant in their sexual behavior and the association of discordance and sexual partnering among those aged 15-44 years from the 2006-2010 National Survey of Family Growth (n = 7,353). Sexual concordance was defined as reporting a heterosexual identity and no female partners in the past year; discordance was reporting a heterosexual identity and having at least one female partner in the past year. Sexual partnering was defined as being concurrent, serially monogamous or monogamous with a male partner in the previous year. Polytomous logistic regression models evaluated the association between sexual discordance and sexual partnering. Among self-identified heterosexual, sexually active women, 11.2 % reported ever having had a same sex partner. Heterosexually discordant women who had both male and female partners in the previous year were 5.5 times as likely to report having a concurrent relationship (95 % CI 2.77-11.09) and 2.4 times as likely to report engaging in serially monogamous relationships (95 % CI 1.19-4.97) with male partners. Discordance between heterosexual identity and same sex behavior is a factor in risky behaviors. Women who have sex with women and men may act as bridges for the transmission of STDs, particularly to their female partners. Sexual education should include information inclusive of non-heteronormative behaviors and identities to provide sexual minorities with the tools and information they need. Clinical guidelines should ensure that all women are offered counseling and screening for reproductive and sexual health. PMID:24718674

  12. The Male Experience of Sexual Violence The FBI annual statistic on sexual assault finds that 1 in 8 men will be sexually

    E-print Network

    Machel, Hans

    assault. Fact: A person's sexual orientation does not change as a result of a sexual assault experience. Some survivors do feel confused about their sexual orientation after a sexual assault or sexual abuseThe Male Experience of Sexual Violence The FBI annual statistic on sexual assault finds that 1 in 8

  13. Sexually transmitted diseases.

    PubMed

    Bechtel, Mark A; Trout, Wayne

    2015-03-01

    Sexually transmitted diseases (STDs) continue to be a global epidemic with significant risk of morbidity/mortality for the fetus. STDs with prominent cutaneous findings including condylomata acuminata, genital herpes infections, and syphilis are reviewed. Important clinical cutaneous findings help aid early diagnosis and facilitate treatment. Condylomata acuminata have the potential of causing cervical cancer, anogenital cancer, and oropharyngeal cancer. Significant advances have been made in human papilloma virus vaccinations and treatment. Genital herpes infection can produce significant physical and emotional distress to the patient and significant potential harm to the fetus. Early clinical recognition of STDs and their appropriate management is critical. PMID:25565081

  14. Sexually Transmitted Infections.

    PubMed

    Smith, Lindsay; Angarone, Michael P

    2015-11-01

    Sexually transmitted infections (STIs) remain a significant burden on public health in the United States. Primary prevention counseling with early diagnosis and treatment remain the best methods to decrease the incidence of STIs. Through significant public heath interventions, the incidence of gonorrhea, Chlamydia, and trichomoniasis is decreasing; however, the incidence of primary and secondary syphilis is increasing. Human papilloma virus remains the most common STI, but new vaccinations have the possibility of having a significant impact on this virus's disease potential. This review discusses the most common STIs in the United States, focusing on clinical presentation, diagnosis, and treatment. PMID:26475947

  15. Species integrity in trees.

    PubMed

    Ortiz-Barrientos, Daniel; Baack, Eric J

    2014-09-01

    From California sequoia, to Australian eucalyptus, to the outstanding diversity of Amazonian forests, trees are fundamental to many processes in ecology and evolution. Trees define the communities that they inhabit, are host to a multiplicity of other organisms and can determine the ecological dynamics of other plants and animals. Trees are also at the heart of major patterns of biodiversity such as the latitudinal gradient of species diversity and thus are important systems for studying the origin of new plant species. Although the role of trees in community assembly and ecological succession is partially understood, the origin of tree diversity remains largely opaque. For instance, the relative importance of differing habitats and phenologies as barriers to hybridization between closely related species is still largely uncharacterized in trees. Consequently, we know very little about the origin of trees species and their integrity. Similarly, studies on the interplay between speciation and tree community assembly are in their infancy and so are studies on how processes like forest maturation modifies the context in which reproductive isolation evolves. In this issue of Molecular Ecology, Lindtke et al. (2014) and Lagache et al. (2014) overcome some traditional difficulties in studying mating systems and sexual isolation in the iconic oaks and poplars, providing novel insights about the integrity of tree species and on how ecology leads to variation in selection on reproductive isolation over time and space. PMID:25155715

  16. Sexual Assault of Adult Males.

    ERIC Educational Resources Information Center

    Stermac, Lana; And Others

    1996-01-01

    Examines the circumstances and characteristics of sexual assaults against adult males presenting to a crisis unit in a large metropolitan area. Most victims were young gay men, many of whom had physical or cognitive disabilities making them particularly vulnerable. Results suggest a need for increased awareness of acquaintance sexual assault in…

  17. Teacher Negotiations of Sexual Subjectivities

    ERIC Educational Resources Information Center

    Ferfolja, Tania

    2007-01-01

    Discrimination often silences and marginalizes those who do not conform to the dominant gender and (hetero)sexual discourses that operate in broader society. This discussion addresses the ways that seventeen self-identified lesbian teachers working in New South Wales (NSW) Australia negotiate their sexual subjectivities at work in order to pass or…

  18. Sexuality, Television and Broadcast Standards.

    ERIC Educational Resources Information Center

    Heller, Melvin S.

    This monograph provides a rationale for contemporary guidelines for the television and broadcast network management of sexual content in proposed progam materials. Beginning with a brief outline of the professional practices and responsibilities of broadcast standards editors, it then explores the relationships between sexual development,…

  19. Sexual Harassment: It's Not Academic

    ERIC Educational Resources Information Center

    US Department of Education, 2008

    2008-01-01

    Sexual harassment of students is illegal. A federal law, "Title IX of the Education Amendments of 1972" ("Title IX"), prohibits discrimination on the basis of sex, including sexual harassment, in education programs and activities. All public and private education institutions that receive any federal funds must comply with "Title IX." "Title IX"…

  20. Freshman Sexual Attitudes and Behavior.

    ERIC Educational Resources Information Center

    Nutt, Roberta L.; Sedlacek, William E.

    At the University of Maryland, 758 randomly selected incoming freshman students were administered an anonymous poll regarding their sexual attitudes and behavior. Results showed that the Maryland freshman generally resembled other U.S. college students in their sexual experience. Approximately half (52% of males, 46% of females) reported that they…

  1. Sexual Revictimization Revisited: A Commentary

    ERIC Educational Resources Information Center

    Gidycz, Christine A.

    2011-01-01

    Since the early 1990s, there has been an increase in scholarly work and theoretical writing on the topic of sexual revictimization--particularly of women. The foundation for this work was set earlier when it was noted that rape and sexual assault were traumatic, more widespread than anyone could ever imagine, and many adult rape victims had…

  2. Intervention Strategies for Sexual Abuse.

    ERIC Educational Resources Information Center

    Rencken, Robert H.

    This book provides a framework for understanding the dimensions (scope, taxonomy, philosophy) and dynamics (individual, familial, and societal) of child sexual abuse. The major focus is on integrated intervention strategies for any professional who must work with incomplete information. Chapter 1 provides an overview of the problem of child sexual

  3. Challenging Sexual Harassment on Campus

    ERIC Educational Resources Information Center

    Baker, Nancy V.

    2010-01-01

    More than thirty years ago, an administrative assistant at Cornell University first challenged her university's indifference to her boss's sexually predatory behavior. While she did not prevail, her case sparked a movement. Litigation, news stories, and government guidelines defining sexual harassment followed. And universities responded: policies…

  4. Firefighting Women and Sexual Harassment.

    ERIC Educational Resources Information Center

    Rosell, Ellen; And Others

    1995-01-01

    Survey responses were received from 37 of 103 department chiefs and 206 of 1,108 female firefighters. The 58% who reported sexual harassment indicated greater stress, sexual stereotyping, acts of violence, use of sick leave, and fear. Although most departments have a policy, over half of those harassed did not report incidents. (SK)

  5. Sexual reproduction in Aspergillus flavus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aspergillus flavus is the major producer of carcinogenic aflatoxins in crops worldwide and is also an important opportunistic human pathogen in aspergillosis. The sexual state of this heterothallic fungus is described from crosses between strains of the opposite mating type. Sexual reproduction oc...

  6. Sexual communication in romantic relationships: An investigation into the disclosure of sexual fantasies

    E-print Network

    Anderson, Michael

    2011-12-31

    that more frequent sexual fantasy contributes to greater sexual desire, more orgasms during intercourse, greater arousability, fewer sexual problems, and even greater sexual satisfaction in general. Researchers have also argued that sexual fantasies may... activity and enhanced sexual experiences. In addition, studies have reported a positive association between orgasmic frequency during sex and frequency of sexual fantasy (Armdt, Foehl, & Good, 1985; Epstein & Smith, 1957; Lentz & Zeiss, 1983; Wilson, 1978...

  7. Mate choice and the Amazon molly: how sexuality and unisexuality can coexist.

    PubMed

    Schlupp, Ingo

    2010-01-01

    One of the most complex and important problems in modern evolutionary biology remains to explain the evolution and persistence of sexual reproduction given the costs of sexuality. One way to study the relative strengths and weaknesses of sexuality and asexuality is to study the dynamics of the coexistence of sexual and asexual organisms. An excellent model system for such an approach is the unisexual Amazon molly, Poecilia formosa. This livebearing fish is clonal, but requires sperm to trigger embryogenesis. Amazon mollies need to obtain sperm from males of closely related species. In an effort to understand the apparently paradoxical coexistence of the Amazon molly with its sexual hosts, many theories were tested, but most seem to have little relevance to understanding stability, whereas male mating behavior is potentially very important. PMID:20421327

  8. Reproducibility of telomere length assessment: an international collaborative study

    E-print Network

    Martin-Ruiz, Carmen M.; Baird, Duncan; Roger, Laureline; Boukamp, Petra; Krunic, Damir; Cawthon, Richard; Dokter, Martin M.; van der Harts, Pim; Bekaert, Sofie; de Meyer, Tim; Roos, Goran; Svenson, Ulrika; Codd, Veryan; Samani, Nilesh J.; McGlynn, Liane; Shiels, Paul G.; Pooley, Karen A.; Dunning, Alison M.; Cooper, Rachel; Wong, Andrew; Kingston, Andrew; von Zglinicki, Thomas

    2014-09-19

    Background: Telomere length is a putative biomarker of ageing, morbidity and mortality. Its application is hampered by lack of widely applicable reference ranges and uncertainty regarding the present limits of measurement reproducibility within...

  9. 15. REPRODUCED FROM 'GRIST WIND MILLS AT EAST HAMPTON,' PICTURESQUE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. REPRODUCED FROM 'GRIST WIND MILLS AT EAST HAMPTON,' PICTURESQUE AMERICA NEW YORK, 1872. THE HOOD WINDMILL IS IN THE FOREGROUND AND THE PANTIGO WINDMILL IS IN THE BACKGROUND - Pantigo Windmill, James Lane, East Hampton, Suffolk County, NY

  10. 8. Historic American Buildings Survey Reproduced from the collections of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Historic American Buildings Survey Reproduced from the collections of the Library of Congress, Accession No. 45041 Geographical File ('Nantucket, Mass.') Division of Prints and Photographs c. 1880 - Jethro Coffin House, Sunset Hill, Nantucket, Nantucket County, MA

  11. KALMAN FILTERING IN REPRODUCING KERNEL HILBERT SPACES PINGPING ZHU

    E-print Network

    Slatton, Clint

    KALMAN FILTERING IN REPRODUCING KERNEL HILBERT SPACES By PINGPING ZHU A DISSERTATION PRESENTED.1.1 Bayesian Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 2.1.2 Kalman Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2.1.3 Nonlinear Kalman Filter . . . . . . . . . . . . . . . . . . . . . . . . 19 2.1.3.1 Extended

  12. Photographic copy of reproduced photograph dated 1942. Exterior view, west ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Photographic copy of reproduced photograph dated 1942. Exterior view, west elevation. Building camouflaged during World War II. - Grand Central Air Terminal, 1310 Air Way, Glendale, Los Angeles County, CA

  13. Sexual selection protects against extinction.

    PubMed

    Lumley, Alyson J; Michalczyk, ?ukasz; Kitson, James J N; Spurgin, Lewis G; Morrison, Catriona A; Godwin, Joanne L; Dickinson, Matthew E; Martin, Oliver Y; Emerson, Brent C; Chapman, Tracey; Gage, Matthew J G

    2015-06-25

    Reproduction through sex carries substantial costs, mainly because only half of sexual adults produce offspring. It has been theorized that these costs could be countered if sex allows sexual selection to clear the universal fitness constraint of mutation load. Under sexual selection, competition between (usually) males and mate choice by (usually) females create important intraspecific filters for reproductive success, so that only a subset of males gains paternity. If reproductive success under sexual selection is dependent on individual condition, which is contingent to mutation load, then sexually selected filtering through 'genic capture' could offset the costs of sex because it provides genetic benefits to populations. Here we test this theory experimentally by comparing whether populations with histories of strong versus weak sexual selection purge mutation load and resist extinction differently. After evolving replicate populations of the flour beetle Tribolium castaneum for 6 to 7 years under conditions that differed solely in the strengths of sexual selection, we revealed mutation load using inbreeding. Lineages from populations that had previously experienced strong sexual selection were resilient to extinction and maintained fitness under inbreeding, with some families continuing to survive after 20 generations of sib × sib mating. By contrast, lineages derived from populations that experienced weak or non-existent sexual selection showed rapid fitness declines under inbreeding, and all were extinct after generation 10. Multiple mutations across the genome with individually small effects can be difficult to clear, yet sum to a significant fitness load; our findings reveal that sexual selection reduces this load, improving population viability in the face of genetic stress. PMID:25985178

  14. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.

    E-print Network

    Spirtes, Peter

    Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. #12;Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. #12;Reproduced with permission of the copyright owner. Further reproduction prohibited without

  15. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.

    E-print Network

    #12;Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. #12;Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. #12;Reproduced with permission of the copyright owner. Further reproduction prohibited without

  16. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.

    E-print Network

    Coble, Theresa G.

    Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. PR EVIEW #12;Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. PR EVIEW #12;Reproduced with permission of the copyright owner. Further reproduction

  17. Sexual selection drives speciation in an Amazonian frog

    USGS Publications Warehouse

    Boul, K.E.; Funk, W.C.; Darst, C.R.; Cannatella, D.C.; Ryan, M.J.

    2007-01-01

    One proposed mechanism of speciation is divergent sexual selection, whereby divergence in female preferences and male signals results in behavioural isolation. Despite the appeal of this hypothesis, evidence for it remains inconclusive. Here, we present several lines of evidence that sexual selection is driving behavioural isolation and speciation among populations of an Amazonian frog (Physalaemus petersi). First, sexual selection has promoted divergence in male mating calls and female preferences for calls between neighbouring populations, resulting in strong behavioural isolation. Second, phylogenetic analysis indicates that populations have become fixed for alternative call types several times throughout the species' range, and coalescent analysis rejects genetic drift as a cause for this pattern, suggesting that this divergence is due to selection. Finally, gene flow estimated with microsatellite loci is an average of 30 times lower between populations with different call types than between populations separated by a similar geographical distance with the same call type, demonstrating genetic divergence and incipient speciation. Taken together, these data provide strong evidence that sexual selection is driving behavioural isolation and speciation, supporting sexual selection as a cause for speciation in the wild. ?? 2006 The Royal Society.

  18. The Relationship Among Sexual Attitudes, Sexual Fantasy, and Religiosity

    PubMed Central

    Ahrold, Tierney K.; Farmer, Melissa; Trapnell, Paul D.; Meston, Cindy M.

    2015-01-01

    Recent research on the impact of religiosity on sexuality has highlighted the role of the individual, and suggests that the effects of religious group and sexual attitudes and fantasy may be mediated through individual differences in spirituality. The present study investigated the role of religion in an ethnically diverse young adult sample (N = 1413, 69% women) using religious group as well as several religiosity domains: spirituality, intrinsic religiosity, paranormal beliefs, and fundamentalism. Differences between religious groups in conservative sexual attitudes were statistically significant but small; as predicted, spirituality mediated these effects. In contrast to the weak effects of religious group, spirituality, intrinsic religiosity, and fundamentalism were strong predictors of women’s conservative sexual attitudes; for men, intrinsic religiosity predicted sexual attitude conservatism but spirituality predicted attitudinal liberalism. For women, both religious group and religiosity domains were significant predictors of frequency of sexual fantasies while, for men, only religiosity domains were significant predictors. These results indicate that individual differences in religiosity domains were better predictors of sexual attitudes and fantasy than religious group and that these associations are moderated by gender. PMID:20364304

  19. Evolution of female remating behaviour following experimental removal of sexual selection

    E-print Network

    Pitnick, Scott

    be fertilized by a single ejaculate in most species. Why females of many species mate with multiple malesEvolution of female remating behaviour following experimental removal of sexual selection Scott Place, Syracuse, NY 13244-1270, USA The relatively small number of ova produced by a female can

  20. Femur bone strength in Tyrannosaurus rex: A study of sexual dimorphism

    NASA Astrophysics Data System (ADS)

    Lee, Scott

    2012-04-01

    Tyrannosaurus rex is the iconic species of a fearsome predator and is held in fascination by virtually everyone. Like many other species, Tyrannosaurs rex displayed sexual dimorphism with the females larger than the males. The femur bones of 14 fossil specimens were examined to determine if the maximum running abilities were significantly different for the two genders. No significant difference is observed.

  1. Sexual reproduction and recombination in the aflatoxin-producing fungus Aspergillus parasiticus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fungal phylum Ascomycota comprises a large proportion of species with no known sexual stage, despite high genetic variability in field populations. One such asexual species, Aspergillus parasiticus, is a potent producer of carcinogenic and hepatotoxic aflatoxins, polyketide-derived secondary me...

  2. Childhood Sexual Abuse and Sexual Risk Behavior among Men and Women Attending a Sexually Transmitted Disease Clinic

    ERIC Educational Resources Information Center

    Senn, Theresa E.; Carey, Michael P.; Vanable, Peter A.; Coury-Doniger, Patricia; Urban, Marguerite A.

    2006-01-01

    Childhood sexual abuse (CSA) is associated with a wide range of negative outcomes. The authors investigated the relation between CSA and sexual risk behavior in 827 patients recruited from a sexually transmitted disease (STD) clinic. Overall, CSA was reported by 53% of women and 49% of men and was associated with greater sexual risk behavior,…

  3. An Examination of Gender Role Identity, Sexual Self-Esteem, Sexual Coercion and Sexual Victimization in a University Sample

    ERIC Educational Resources Information Center

    Kelly, Theresa C.; Erickson, Chris D.

    2007-01-01

    The relationship between gender role identity, sexual self-esteem and sexual coercion was examined through a questionnaire. Participants were 84 undergraduate students from a university in Washington, DC. Contrary to what has been found in the literature, there were weak relationships between sexual coercion and masculinity, and sexual coercion…

  4. On The Reproducibility of Seasonal Land-surface Climate

    SciTech Connect

    Phillips, T J

    2004-10-22

    The sensitivity of the continental seasonal climate to initial conditions is estimated from an ensemble of decadal simulations of an atmospheric general circulation model with the same specifications of radiative forcings and monthly ocean boundary conditions, but with different initial states of atmosphere and land. As measures of the ''reproducibility'' of continental climate for different initial conditions, spatio-temporal correlations are computed across paired realizations of eleven model land-surface variables in which the seasonal cycle is either included or excluded--the former case being pertinent to climate simulation, and the latter to seasonal anomaly prediction. It is found that the land-surface variables which include the seasonal cycle are impacted only marginally by changes in initial conditions; moreover, their seasonal climatologies exhibit high spatial reproducibility. In contrast, the reproducibility of a seasonal land-surface anomaly is generally low, although it is substantially higher in the Tropics; its spatial reproducibility also markedly fluctuates in tandem with warm and cold phases of the El Nino/Southern Oscillation. However, the overall degree of reproducibility depends strongly on the particular land-surface anomaly considered. It is also shown that the predictability of a land-surface anomaly implied by its reproducibility statistics is consistent with what is inferred from more conventional predictability metrics. Implications of these results for climate model intercomparison projects and for operational forecasts of seasonal continental climate also are elaborated.

  5. Applicability of Density Functional Theory in Reproducing Accurate Vibrational Spectra of Surface Bound Species

    SciTech Connect

    Matanovic, Ivana; Atanassov, Plamen; Kiefer, Boris; Garzon, Fernando; Henson, Neil J.

    2014-10-05

    The structural equilibrium parameters, the adsorption energies, and the vibrational frequencies of the nitrogen molecule and the hydrogen atom adsorbed on the (111) surface of rhodium have been investigated using different generalized-gradient approximation (GGA), nonlocal correlation, meta-GGA, and hybrid functionals, namely, Perdew, Burke, and Ernzerhof (PBE), Revised-RPBE, vdW-DF, Tao, Perdew, Staroverov, and Scuseria functional (TPSS), and Heyd, Scuseria, and Ernzerhof (HSE06) functional in the plane wave formalism. Among the five tested functionals, nonlocal vdW-DF and meta-GGA TPSS functionals are most successful in describing energetics of dinitrogen physisorption to the Rh(111) surface, while the PBE functional provides the correct chemisorption energy for the hydrogen atom. It was also found that TPSS functional produces the best vibrational spectra of the nitrogen molecule and the hydrogen atom on rhodium within the harmonic formalism with the error of 22.62 and 21.1% for the NAN stretching and RhAH stretching frequency. Thus, TPSS functional was proposed as a method of choice for obtaining vibrational spectra of low weight adsorbates on metallic surfaces within the harmonic approximation. At the anharmonic level, by decoupling the RhAH and NAN stretching modes from the bulk phonons and by solving one- and two-dimensional Schr€odinger equation associated with the RhAH, RhAN, and NAN potential energy we calculated the anharmonic correction for NAN and RhAH stretching modes as 231 cm21 and 277 cm21 at PBE level. Anharmonic vibrational frequencies calculated with the use of the hybrid HSE06 function are in best agreement with available experiments.

  6. Extensive outcrossing and androdioecy in a vertebrate species that otherwise reproduces

    E-print Network

    Avise, John

    Androdioecy is a rare reproductive system in which a natural population consists of functional males, gonochoristic males occur at 20% frequency in a natural population at Twin Cays, Belize. Here we use a battery in Florida, where males are much rarer. These findings document that outcrossing (probably be- tween

  7. Adolescent's sexual problems in Korea.

    PubMed

    Kang, B S

    1990-07-01

    This article discusses primary contributors of sexual problems among Korean adolescents. As a result of improved nutrition, physical maturity is occurring at an earlier age in Korean youths. On the other hand, marital age has increased; the average age for males to marry is 27.3 years and 24.1 years in females. Hence, these factors extend the time frame between onset of sexual maturity and marriage. Enrollment in schools has risen; middle school registration has increased from 74.2% in 1975 to 99.7% in 1985 and from 43.6% to 78.3% in high schools. Increased enrollment has also been observed at the university level which may promote prolonged educational periods; this focus on education may reduce sexual interest among students. Improved employment opportunities may also influence sexual behavior among adolescents; urban migration can encourage casual relationships. Changes in family structure and sexual morals has promoted liberal attitudes regarding sexual practices. Increased exposure to mass media has affected adolescent sexual problems; 99.1% of the households in 1985 possessed televisions. These sexual problems include onset of sexual intercourse at an earlier age, unwanted pregnancies, increased induced abortions, and early childbirth. Overall, sexual activity in females has risen from 3.6% in 1965 to 14.5% in 1981 and from 18.5% in 1971 for males to 27.7% in 1981. Pre-marital pregnancy rates have continually increased since 1950; this has resulted in a rise of unwed mothers' consultations which reflects adolescent childbirths. Sex-related crime have also increased; rape ranks 3rd in crimes committed by Korean youth. Sex education and family planning should be provided for adolescents. Furthermore, counseling services should be available to youth regarding unwanted pregnancies, sexually transmitted diseases, and contraception. The Planned Parenthood Federation of Korea provides youth sex telephone services in which adolescents can acquire information on sexual matters. Proposals needing implementation include family life education for parents and their children, sex education and counseling within the school systems, treatment centers for sexually transmitted diseases and pre/post natal care, and youth counseling centers. PMID:12316430

  8. Sexual practices in Malaysia: determinants of sexual intercourse among unmarried youths.

    PubMed

    Zulkifli, S N; Low, W Y

    2000-10-01

    This paper describes findings on selected determinants of sexual intercourse among 468 unmarried adolescents from a survey in Malaysia. Data on respondents' background, sexual experience, contraceptive use, and sexual attitudes are provided. Based on multiple logistic regressions, factors significantly predictive of sexual experience are gender, employment, and sexual attitudes. PMID:11008091

  9. Positive and negative cognitions of sexual submission: relationship to sexual violence.

    PubMed

    Renaud, Cheryl A; Byers, Sandra E

    2006-08-01

    This study investigated gender differences in cognitions of sexual submission as well as their association with sexual violence. Participants were 292 heterosexual undergraduate students who completed a 56-item checklist assessing positive and negative sexual cognitions; they also completed measures assessing experiences of sexual abuse in childhood, experiences of sexual coercion in adulthood, and use of sexual coercion. Two 10-item sexual submission subscales were developed from the checklist. One reflected how often respondents had experienced the sexual submission items as positive. The other reflected how often these items were experienced as negative. When overall frequency of sexual cognitions was controlled, compared to the men, the women reported a significantly greater frequency of both positive and negative cognitions of sexual submission. Submission cognitions were more often negative for women and were more often positive for men. Men and women who had experienced sexual abuse in childhood reported more frequent positive sexual submission cognitions but not more negative sexual submission cognitions. Conversely, men and women who had experienced sexual coercion in adulthood reported more frequent negative sexual submission cognitions but not more positive sexual submission cognitions. Having used sexual coercion was associated with more frequent positive cognitions of sexual submission for both men and women. Implications for the proposed links between sexual violence and preferences for cognitions of sexual submission are discussed. PMID:16909319

  10. Differences between Sexually Victimized and Nonsexually Victimized Male Adolescent Sexual Abusers: Developmental Antecedents and Behavioral Comparisons

    ERIC Educational Resources Information Center

    Burton, David L.; Duty, Kerry Jo; Leibowitz, George S.

    2011-01-01

    This study compares sexually victimized and nonsexually victimized male adolescent sexual abusers on a number of variables. Self-report measures were administered to 325 male sexually abusive youth (average age 16) in six residential facilities in the Midwest, 55% of whom reported sexual victimization. The results indicate that the sexually

  11. talking about Sexual iSSueS: gender and Sexual orientation

    E-print Network

    Sexual issues, do health professional and patient genders Matter? When talking about sexual issues the importance of gender mean that male health professionals are unable to comprehend the sexual experiencesChapter 7 talking about Sexual iSSueS: gender and Sexual orientation Intuitively, there might seem

  12. Sexual Harassment: What Your Staff Should Know.

    ERIC Educational Resources Information Center

    Shulman, Jacqueline T.

    1995-01-01

    An attorney provides the legal background for sexual harassment suits. Defines actions that school administrators can take to limit exposure to a charge of sexual harassment or to provide a good defense once a charge has been filed. Contains a sample effective sexual harassment policy and a 17-item sexual harassment quiz. (MLF)

  13. Sexual Harassment: State of the Law.

    ERIC Educational Resources Information Center

    Culverhouse, Renee D.

    Sexual harassment under the Equal Employment Opportunity Commission guidelines involves unwelcome sexual advances, requests for sexual favors, or other verbal or physical conduct of a sexual nature, as it applies to males or females in business situations. Harassment is discriminatory when females must act differently than males in order to…

  14. Body size differences do not arise from divergent mate preferences in a species pair of threespine stickleback

    PubMed Central

    Head, Megan L; Price, Emily A.; Boughman, Janette W.

    2009-01-01

    Ecological speciation can be driven by divergent natural and/or sexual selection. The relative contribution of these processes to species divergence, however, is unknown. Here, we investigate how sexual selection in the form of male and female mate preferences contributes to divergence of body size. This trait is known be under divergent natural selection and also contributes to sexual isolation in species pairs of threespine sticklebacks (Gasterosteus aculeatus). We show that neither female nor male size preferences contribute to body size divergence in this species pair, suggesting that size-based sexual isolation arises primarily through natural selection. PMID:19474072

  15. Flibanserin for female sexual dysfunction.

    PubMed

    Reviriego, C

    2014-08-01

    Hypoactive sexual desire disorder (HSDD) is the most commonly described form of female sexual dysfunction. There is currently no pharmacological therapy approved to treat HSDD, and therefore, there is an unmet medical need for the development of efficacious treatment alternatives. Flibanserin is a novel, non-hormonal drug for the treatment of HSDD in pre- and postmenopausal women, although the application submitted to the U.S. Food and Drug Administration by Sprout Pharmaceuticals is only for premenopausal women. Flibanserin works by correcting an imbalance of the levels of the neurotransmitters that affect sexual desire. More specifically, flibanserin increases dopamine and norepinephrine, both responsible for sexual excitement, and decreases serotonin, responsible for sexual inhibition. Clinically, flibanserin has exhibited some encouraging results in terms of its ability to increase the frequency of satisfying sexual events, and the intensity of sexual desire. However, adverse events such as dizziness, nausea, fatigue and somnolence, typical of a centrally acting drug, are also frequently related to flibanserin treatment. PMID:25187905

  16. The sexually abused battered child.

    PubMed

    Hobbs, C J; Wynne, J M

    1990-04-01

    A total of 130 children were identified in whom both evidence of sexual abuse and non-accidental, non-genital physical injuries (bruises, fractures, scratches, burns and scalds, including failure to thrive) were found. There were 77 girls and 53 boys with mean ages 5.7 and 6.8 years respectively and the peak age between the second and seventh birthdays; this reflects previous reports indicating that physical and sexual abuse predominantly involves young children. Patterns of injury that suggested sexually motivated assault included bruises, scratches, and burns around the lower trunk and genitalia, thighs, buttocks, and upper legs including knees. Pinch and grip marks were found where the child was held. The sexual abuse often involved attempted or achieved penetration of mouth, vagina, or anus, and physical signs were seen relatively more often than in sexually abused children as a whole. Four children died and sexual aggression and child death in the domestic setting may be linked. One in six of 769 physically abused children (16.9%) and one in seven of 949 sexually abused children (13.6%) have suffered both forms of abuse. PMID:2346335

  17. Selective advantage for sexual reproduction

    NASA Astrophysics Data System (ADS)

    Tannenbaum, Emmanuel

    2006-06-01

    This paper develops a simplified model for sexual reproduction within the quasispecies formalism. The model assumes a diploid genome consisting of two chromosomes, where the fitness is determined by the number of chromosomes that are identical to a given master sequence. We also assume that there is a cost to sexual reproduction, given by a characteristic time ?seek during which haploid cells seek out a mate with which to recombine. If the mating strategy is such that only viable haploids can mate, then when ?seek=0 , it is possible to show that sexual reproduction will always out compete asexual reproduction. However, as ?seek increases, sexual reproduction only becomes advantageous at progressively higher mutation rates. Once the time cost for sex reaches a critical threshold, the selective advantage for sexual reproduction disappears entirely. The results of this paper suggest that sexual reproduction is not advantageous in small populations per se, but rather in populations with low replication rates. In this regime, the cost for sex is sufficiently low that the selective advantage obtained through recombination leads to the dominance of the strategy. In fact, at a given replication rate and for a fixed environment volume, sexual reproduction is selected for in high populations because of the reduced time spent finding a reproductive partner.

  18. Selective advantage for sexual reproduction

    NASA Astrophysics Data System (ADS)

    Tannenbaum, Emmanuel

    2006-03-01

    We develop a simplified model for sexual replication within the quasispecies formalism. We assume that the genomes of the replicating organisms are two-chromosomed and diploid, and that the fitness is determined by the number of chromosomes that are identical to a given master sequence. We also assume that there is a cost to sexual replication, given by a characteristic time ?seek during which haploid cells seek out a mate with which to recombine. If the mating strategy is such that only viable haploids can mate, then when ?seek= 0 , it is possible to show that sexual replication will always outcompete asexual replication. However, as ?seek increases, sexual replication only becomes advantageous at progressively higher mutation rates. Once the time cost for sex reaches a critical threshold, the selective advantage for sexual replication disappears entirely. The results of this talk suggest that sexual replication is not advantageous in small populations per se, but rather in populations with low replication rates. In this regime, the cost for sex is sufficiently low that the selective advantage obtained through recombination leads to the dominance of the strategy. In fact, at a given replication rate and for a fixed environment volume, sexual replication is selected for in high populations because of the reduced time spent finding a reproductive partner.

  19. Sexually selected dichromatism in the hihi Notiomystis cincta: multiple colours for multiple receivers

    PubMed Central

    Walker, L K; Ewen, J G; Brekke, P; Kilner, R M

    2014-01-01

    Why do some bird species show dramatic sexual dichromatism in their plumage? Sexual selection is the most common answer to this question. However, other competing explanations mean it is unwise to assume that all sexual dichromatism has evolved by this mechanism. Even if sexual selection is involved, further work is necessary to determine whether dichromatism results from competition amongst rival males, or by female choice for attractive traits, or both. Here, we test whether sexually dichromatic hihi (Notiomystis cincta) plumage is currently under sexual selection, with detailed behavioural and genetic analyses of a free-living island population. Bateman gradients measured for males and females reveal the potential for sexual selection, whilst selection gradients, relating reproductive success to specific colourful traits, show that there is stabilizing selection on white ear tuft length in males. By correlating colourful male plumage with different components of reproductive success, we show that properties of yellow plumage are most likely a product of male–male competition, whilst properties of the black and white plumage are an outcome of both male–male competition and female choice. Male plumage therefore potentially signals to multiple receivers (rival males and potential mates), and this may explain the multicoloured appearance of one of the most strikingly dichromatic species in New Zealand. PMID:24836349

  20. Sexual Ornaments, Body Morphology, and Swimming Performance in Naturally Hybridizing Swordtails (Teleostei: Xiphophorus)

    PubMed Central

    Johnson, James B.; Macedo, Danielle C.; Passow, Courtney N.; Rosenthal, Gil G.

    2014-01-01

    Determining the costs of sexual ornaments is complicated by the fact that ornaments are often integrated with other, non-sexual traits, making it difficult to dissect the effect of ornaments independent of other aspects of the phenotype. Hybridization can produce reduced phenotypic integration, allowing one to evaluate performance across a broad range of multivariate trait values. Here we assess the relationship between morphology and performance in the swordtails Xiphophorus malinche and X. birchmanni, two naturally-hybridizing fish species that differ extensively in non-sexual as well as sexual traits. We took advantage of novel trait variation in hybrids to determine if sexual ornaments incur a cost in terms of locomotor ability. For both fast-start and endurance swimming, hybrids performed at least as well as the two parental species. The sexually-dimorphic sword did not impair swimming performance per se. Rather, the sword negatively affected performance only when paired with a sub-optimal body shape. Studies seeking to quantify the costs of ornaments should consider that covariance with non-sexual traits may create the spurious appearance of costs. PMID:25329558

  1. Data reproducibility from an inertial kinetic exercise machine.

    PubMed

    Caruso, John F; Kucera, Sam C; Hari, Parmeswar K; Mc Lagan, Jessica R; Olson, Nathan M; Shepherd, Catherine M; Marshall, Mallory R

    2010-11-01

    An inertial kinetic exercise (IKE, Oconomowoc, WI, USA) machine was created that permits high-velocity workouts suited for injury rehabilitation and speed development in athletes. In addition, its design does not entail the movement of resistance against Earth's gravitational pull. Thus, the design and operation associated with the IKE may be incorporated into novel environments such as space flight. Yet before it can be used for such reasons, IKE data reproducibility must first be ascertained, which serves as the present study's purpose. Methods to assess data reproducibility required subjects (n = 42) to perform 2 IKE elbow flexor trials, each comprising two 60-second sets separated by a 90-second rest. Preceded by a familiarization session on the IKE, subjects were instructed to perform high-speed elbow flexor trial repetitions in good form. Instrumentation entailed an accelerometer and a computer interfaced with software. Maximum and average forces (MF, AF), as well as work (W), were examined for reproducibility with several test-retest measures. Results showed high reproducibility, yet intertrial variability was greater due in part to the length of time between exercise sessions. It was concluded that MF reproducibility was inherently less partly due to the nature of the variable, which entailed a single instantaneous expression over each 60-second set. In contrast, AF and W denoted a cumulative, and thus better overall, representation of total exercise performance. Based on our high reproducibility values, present IKE instrumentation methods appear to be appropriate. Practical applications suggest that coaches and therapists may want to employ an IKE as instrumented in the present study to derive reproducible performance data on people who may use the device under their supervision. PMID:20168257

  2. The structural influence of family and parenting on young people's sexual and reproductive health in rural northern Tanzania

    PubMed Central

    Wamoyi, Joyce; Wight, Daniel; Remes, Pieter

    2015-01-01

    This paper explores the structural role of the family and parenting in young people's sexual and reproductive health. The study involved eight weeks of participant observation, 26 in-depth interviews, and 11 group discussions with young people aged 14–24 years, and 20 in-depth interviews and 6 group discussions with parents/carers of children in this age group. At an individual level, parenting and family structure were found to affect young people's sexual behaviour by influencing children's self-confidence and interactional competence, limiting discussion of sexual health and shaping economic provision for children, which in turn affected parental authority and daughters' engagement in risky sexual behaviour. Sexual norms are reproduced both through parents' explicit prohibitions and their own behaviours. Girls are socialised to accept men's superiority, which shapes their negotiation of sexual relationships. Interventions to improve young people's sexual and reproductive health should recognise the structural effects of parenting, both in terms of direct influences on children and the dynamics by which structural barriers such as gendered power relations and cultural norms around sexuality are transmitted across generations. PMID:25597368

  3. The sexually sadistic serial killer.

    PubMed

    Warren, J I; Hazelwood, R R; Dietz, P E

    1996-11-01

    This article explores characteristics and crime scene behavior of 20 sexually sadistic serial murderers. The pairing of character pathology with paraphilic arousal to the control and degradation of others is examined as it manifests itself in their murders. Commonalities across murders and across murderers are highlighted, i.e., the execution of murders that are well-planned, the use of preselected locations, captivity, a variety of painful sexual acts, sexual bondage, intentional torture, and death by means of strangulation and stabbing. PMID:8914287

  4. Mate choice and sexual selection: What have we learned since Darwin?

    PubMed Central

    Jones, Adam G.; Ratterman, Nicholas L.

    2009-01-01

    Charles Darwin laid the foundation for all modern work on sexual selection in his seminal book The Descent of Man, and Selection in Relation to Sex. In this work, Darwin fleshed out the mechanism of sexual selection, a hypothesis that he had proposed in The Origin of Species. He went well beyond a simple description of the phenomenon by providing extensive evidence and considering the far-reaching implications of the idea. Here we consider the contributions of Darwin to sexual selection with a particular eye on how far we have progressed in the last 150 years. We focus on 2 key questions in sexual selection. First, why does mate choice evolve at all? And second, what factors determine the strength of mate choice (or intensity of sexual selection) in each sex? Darwin provided partial answers to these questions, and the progress that has been made on both of these topics since his time should be seen as one of the great triumphs of modern evolutionary biology. However, a review of the literature shows that key aspects of sexual selection are still plagued by confusion and disagreement. Many of these areas are complex and will require new theory and empirical data for complete resolution. Overall, Darwin's contributions are still surprisingly relevant to the modern study of sexual selection, so students of evolutionary biology would be well advised to revisit his works. Although we have made significant progress in some areas of sexual selection research, we still have much to accomplish. PMID:19528643

  5. Does the avoidance of sexual costs increase fitness in asexual invaders?

    PubMed Central

    Stelzer, Claus-Peter

    2015-01-01

    The high prevalence of sexual reproduction is considered a paradox mainly for two reasons. First, asexuals should enjoy various growth benefits because they seemingly rid themselves of the many inefficiencies of sexual reproduction—the so-called costs of sex. Second, there seems to be no lack of asexual origins because losses of sexual reproduction have been described in almost every larger eukaryotic taxon. Current attempts to resolve this paradox concentrate on a few hypotheses that provide universal benefits that would compensate for these costs and give sexual reproduction a net advantage. However, are new asexual lineages really those powerful invaders that could quickly displace their sexual ancestors? Research on the costs of sex indicates that sex is often stabilized by highly lineage-specific mechanisms. Two main categories can be distinguished. First are beneficial traits that evolved within a particular species and became tightly associated with sex (e.g., a mating system that involves sexual selection, or a sexual diapausing stage that allows survival through harsh periods). If such traits are absent in asexuals, simple growth efficiency considerations will not capture the fitness benefits gained by skipping sexual reproduction. Second, lineage-specific factors might prevent asexuals from reaching their full potential (e.g., dependence on fertilization in sperm-dependent parthenogens). Such observations suggest that the costs of sex are highly variable and often lower than theoretical considerations suggest. This has implications for the magnitude of universal benefits required to resolve the paradox of sex. PMID:26195736

  6. Does the avoidance of sexual costs increase fitness in asexual invaders?

    PubMed

    Stelzer, Claus-Peter

    2015-07-21

    The high prevalence of sexual reproduction is considered a paradox mainly for two reasons. First, asexuals should enjoy various growth benefits because they seemingly rid themselves of the many inefficiencies of sexual reproduction-the so-called costs of sex. Second, there seems to be no lack of asexual origins because losses of sexual reproduction have been described in almost every larger eukaryotic taxon. Current attempts to resolve this paradox concentrate on a few hypotheses that provide universal benefits that would compensate for these costs and give sexual reproduction a net advantage. However, are new asexual lineages really those powerful invaders that could quickly displace their sexual ancestors? Research on the costs of sex indicates that sex is often stabilized by highly lineage-specific mechanisms. Two main categories can be distinguished. First are beneficial traits that evolved within a particular species and became tightly associated with sex (e.g., a mating system that involves sexual selection, or a sexual diapausing stage that allows survival through harsh periods). If such traits are absent in asexuals, simple growth efficiency considerations will not capture the fitness benefits gained by skipping sexual reproduction. Second, lineage-specific factors might prevent asexuals from reaching their full potential (e.g., dependence on fertilization in sperm-dependent parthenogens). Such observations suggest that the costs of sex are highly variable and often lower than theoretical considerations suggest. This has implications for the magnitude of universal benefits required to resolve the paradox of sex. PMID:26195736

  7. Genetics of decayed sexual traits in a parasitoid wasp with endosymbiont-induced asexuality.

    PubMed

    Ma, W-J; Pannebakker, B A; Beukeboom, L W; Schwander, T; van de Zande, L

    2014-11-01

    Trait decay may occur when selective pressures shift, owing to changes in environment or life style, rendering formerly adaptive traits non-functional or even maladaptive. It remains largely unknown if such decay would stem from multiple mutations with small effects or rather involve few loci with major phenotypic effects. Here, we investigate the decay of female sexual traits, and the genetic causes thereof, in a transition from haplodiploid sexual reproduction to endosymbiont-induced asexual reproduction in the parasitoid wasp Asobara japonica. We take advantage of the fact that asexual females cured of their endosymbionts produce sons instead of daughters, and that these sons can be crossed with sexual females. By combining behavioral experiments with crosses designed to introgress alleles from the asexual into the sexual genome, we found that sexual attractiveness, mating, egg fertilization and plastic adjustment of offspring sex ratio (in response to variation in local mate competition) are decayed in asexual A. japonica females. Furthermore, introgression experiments revealed that the propensity for cured asexual females to produce only sons (because of decayed sexual attractiveness, mating behavior and/or egg fertilization) is likely caused by recessive genetic effects at a single locus. Recessive effects were also found to cause decay of plastic sex-ratio adjustment under variable levels of local mate competition. Our results suggest that few recessive mutations drive decay of female sexual traits, at least in asexual species deriving from haplodiploid sexual ancestors. PMID:24781809

  8. Evaluating child sexual abuse.

    PubMed

    Giardino, Angelo P; Finkel, Martin A

    2005-05-01

    We have learned much about the medical evaluation of suspected child sexual abuse during the past 2 decades. The physical examination still holds an important place in the evaluation but is secondary to a well-performed history. As the evolving literature increases our understanding, the relevance of various anatomic appearances of the prepubertal and pubertal genital examination will certainly become even clearer. The physical examination rarely is diagnostic by itself, with more than 92% of cases failing to demonstrate either acute or chronic signs of injury. Thus, the 1994 quote by Adams and colleagues, "It's normal to be normal," continues to ring true, now supported by a growing body of pediatric literature. PMID:15948349

  9. [Sexuality, heart and chocolate].

    PubMed

    Bianchi-Demicheli, F; Sekoranja, L; Pechčre-Bertschi, A

    2013-03-20

    All along the history, many kinds of magic and aphrodisiac properties were attributed to the chocolate. Because of the presence of certain active substances, cacao and chocolate are supposed to have some potentially beneficial effects on human health, particularly on cardiovascular system. Containing flavoniods, cacao and its products have antioxidant, anti-inflammatory, anti-atherogenic, anti-thrombotic, antihypertensive and neuroprotective effects, as well as influence on insulin sensitivity, vascular endothelial function, and activation of nitric oxide. Other molecules, like methyxantin, biogenic amines and cannabinoid-like fatty acids, may have a psychoactive action. Synergic effect of all these substances could have a positive direct and indirect influence on sexual health and function. Nevertheless, randomized studies are needed to confirm these hypotheses and to elaborate recommendations about cacao consumption. PMID:23547364

  10. Sexual revictimization, PTSD, and problem drinking in sexual assault survivors.

    PubMed

    Ullman, Sarah E

    2016-02-01

    Posttraumatic stress disorder (PTSD) and problem drinking are common and often co-occurring sequelae experienced by women survivors of adult sexual assault, yet revictimization may mediate risk of symptoms over time. Structural equation modeling was used to examine data from a 3-wave panel design with a large (N=1012), ethnically diverse sample of women assault survivors to examine whether repeated sexual victimization related to greater PTSD and problem drinking. Structural equation modeling revealed that child sexual abuse was associated with greater symptoms of PTSD and problem drinking and intervening sexual victimization was associated with greater symptoms of PTSD and problem drinking at both 1 and 2year follow-ups. We found no evidence, however, that PTSD directly influenced problem drinking over the long term or vice versa, although they were correlated at each timepoint. Revictimization during the study predicted survivors' prospective PTSD and problem drinking symptoms inconsistently. Implications and recommendations for future research are discussed. PMID:26414205

  11. Sexual Offender Laws and Prevention of Sexual Violence or Recidivism

    PubMed Central

    2010-01-01

    Sexual violence is a significant public health problem in the United States. In an effort to decrease the incidence of sexual assault, legislators have passed regulatory laws aimed at reducing recidivism among convicted sexual offenders. As a result, sex offenders living in the United States are bound by multiple policies, including registration, community notification, monitoring via a global positioning system, civil commitment, and residency, loitering, and Internet restrictions. These policies have led to multiple collateral consequences, creating an ominous environment that inhibits successful reintegration and may contribute to an increasing risk for recidivism. In fact, evidence on the effectiveness of these laws suggests that they may not prevent recidivism or sexual violence and result in more harm than good. PMID:20075329

  12. Transposable elements in sexual and ancient asexual taxa

    PubMed Central

    Arkhipova, Irina; Meselson, Matthew

    2000-01-01

    Sexual reproduction allows deleterious transposable elements to proliferate in populations, whereas the loss of sex, by preventing their spread, has been predicted eventually to result in a population free of such elements [Hickey, D. A. (1982) Genetics 101, 519–531]. We tested this expectation by screening representatives of a majority of animal phyla for LINE-like and gypsy-like reverse transcriptases and mariner/Tc1-like transposases. All species tested positive for reverse transcriptases except rotifers of the class Bdelloidea, the largest eukaryotic taxon in which males, hermaphrodites, and meiosis are unknown and for which ancient asexuality is supported by molecular genetic evidence. Mariner-like transposases are distributed sporadically among species and are present in bdelloid rotifers. The remarkable lack of LINE-like and gypsy-like retrotransposons in bdelloids and their ubiquitous presence in other taxa support the view that eukaryotic retrotransposons are sexually transmitted nuclear parasites and that bdelloid rotifers evolved asexually. PMID:11121049

  13. Chemical ecology and pollinator-driven speciation in sexually deceptive orchids.

    PubMed

    Ayasse, Manfred; Stökl, Johannes; Francke, Wittko

    2011-09-01

    Sexually deceptive orchids mimic females of their pollinator species to attract male insects for pollination. Pollination by sexual deception has independently evolved in European, Australian, South African, and South American orchid taxa. Reproductive isolation is mainly based on pre-mating isolation barriers, the specific attraction of males of a single pollinator species, mostly bees, by mimicking the female species-specific sex-pheromone. However, in rare cases post-mating barriers have been found. Sexually deceptive orchids are ideal candidates for studies of sympatric speciation, because key adaptive traits such as the pollinator-attracting scent are associated with their reproductive success and with pre-mating isolation. During the last two decades several investigations studied processes of ecological speciation in sexually deceptive orchids of Europe and Australia. Using various methods like behavioural experiments, chemical, electrophysiological, and population-genetic analyses it was shown that minor changes in floral odour bouquets might be the driving force for pollinator shifts and speciation events. New pollinators act as an isolation barrier towards other sympatrically occurring species. Hybridization occurs because of similar odour bouquets of species and the overlap of flowering periods. Hybrid speciation can also lead to the displacement of species by the hybrid population, if its reproductive success is higher than that in the parental species. PMID:21497864

  14. Using prediction markets to estimate the reproducibility of scientific research

    PubMed Central

    Dreber, Anna; Pfeiffer, Thomas; Almenberg, Johan; Isaksson, Siri; Wilson, Brad; Chen, Yiling; Nosek, Brian A.; Johannesson, Magnus

    2015-01-01

    Concerns about a lack of reproducibility of statistically significant results have recently been raised in many fields, and it has been argued that this lack comes at substantial economic costs. We here report the results from prediction markets set up to quantify the reproducibility of 44 studies published in prominent psychology journals and replicated in the Reproducibility Project: Psychology. The prediction markets predict the outcomes of the replications well and outperform a survey of market participants’ individual forecasts. This shows that prediction markets are a promising tool for assessing the reproducibility of published scientific results. The prediction markets also allow us to estimate probabilities for the hypotheses being true at different testing stages, which provides valuable information regarding the temporal dynamics of scientific discovery. We find that the hypotheses being tested in psychology typically have low prior probabilities of being true (median, 9%) and that a “statistically significant” finding needs to be confirmed in a well-powered replication to have a high probability of being true. We argue that prediction markets could be used to obtain speedy information about reproducibility at low cost and could potentially even be used to determine which studies to replicate to optimally allocate limited resources into replications. PMID:26553988

  15. [Reproducible marginal gap measurements of partial ceramic crowns].

    PubMed

    Smeets, M W; Rhemrev, G E; van Waas, M A; Denissen, H W

    1999-09-01

    Aim of this research was to test the hypothesis that marginal gap measurements by a digital microscopic image processing computer are reproducible. Light microscopic images of the margins of Artglass partial crowns on stone dies were obtained with a 3CCD color video camera, digitized and processed. Ten measuring points were painted on a 0.5 mm section of the finish line of the preparation. The opposite corresponding measuring points on the margin of the partial crown were painted as well. The distance (marginal gap) between two corresponding points was painted and calculated by the computer. Reproducibility (precision) is reflected in the ability to reproduce the same measurement results in repeated measurements (n = 5). The reproducibility error was expressed as the coefficient of variation (CV) in percent (%). The localization of the corresponding measurement points and the calculation of the marginal gap were performed without errors. For a marginal gap between 15-50 microns the average measurement error was 3% or 0.45-1.5 microns. It was concluded that the measurement of the gap between two points by the digital image processing computer was reproducible. The measurement error was neglectable given that a clinically acceptable marginal gap is 100 microns. PMID:11930434

  16. Relating Sexual Sadism and Psychopathy to One Another, Non-Sexual Violence, and Sexual Crime Behaviors

    PubMed Central

    Robertson, Carrie A.; Knight, Raymond A.

    2014-01-01

    Sexual sadism and psychopathy have been theoretically, clinically, and empirically linked to violence. Although both constructs are linked to predatory violence, few studies have sought to explore the covariation of the two constructs, and even fewer have sought to conceptualize the similarities of violence prediction in each. The current study considered all four Psychopathy Checklist-Revised (PCL-R) facets and employed well-defined, validated measures of sadism to elucidate the relation between sadism and psychopathy, as well as to determine the role of each in the prediction of non-sexual violence and sexual crime behaviors. Study 1 assessed 314 adult, male sex offenders using archival ratings, as well as the self-report Multidimensional Inventory of Development, Sex, and Aggression (the MIDSA). Study 2 used archival ratings to assess 599 adult, male sex offenders. Exploratory and confirmatory factor analyses of crime scene descriptions yielded four sexual crime behavior factors: Violence, Physical Control, Sexual Behavior, and Paraphilic. Sadism and psychopathy covaried, but were not coextensive; sadism correlated with Total PCL-R, Facet 1, and Facet 4 scores. The constructs predicted all non-sexual violence measures, but predicted different sexual crime behavior factors. The PCL-R facets collectively predicted the Violence and Paraphilic factors, whereas sadism only predicted the Violence factor. PMID:24019144

  17. Sexual Compulsivity and Sexual Risk in Gay and Bisexual Men

    PubMed Central

    Grov, Christian; Parsons, Jeffrey T.; Bimbi, David S.

    2010-01-01

    Much of our understanding of the association between the Sexual Compulsivity Scale (SCS; Kalichman et al., 1994) and sexual risk behavior among men who have sex with men (MSM) has been limited to samples of HIV positive MSM only. Using data from a community-based survey of gay and bisexual men (n = 1214), this analysis sought to further evaluate the association between the SCS and sexual risk behavior. The SCS was significantly associated with a variety of sexual risk behaviors, including having sex under the influence of club drugs, engaging in unprotected anal sex (receptive or insertive) with partners of the same and/or different HIV serostatus, identity as a barebacker, intentions to have bareback sex, number of recent sex partners, and temptation for unsafe sex. The SCS was also significantly associated with having engaged in a variety of specialized sexual behaviors (i.e., fetishes), many of which can increase HIV transmission risks. Finally, in multivariate analyses, the SCS significantly predicted unprotected sex with a non-main partner even when controlling for race, HIV serostatus, age, identity as a barebacker, and club drug use. These data indicate that the SCS may be able to serve as an indicator to detect HIV-associated sexual risk behavior in community-based samples of gay and bisexual men. PMID:19308715

  18. Intralocus Sexual Conflict Diminishes the Benefits of Sexual Selection

    PubMed Central

    Pischedda, Alison; Chippindale, Adam K

    2006-01-01

    Evolution based on the benefits of acquiring “good genes” in sexual selection is only plausible with the reliable transmission of genetic quality from one generation to the next. Accumulating evidence suggests that sexually antagonistic (SA) genes with opposite effects on Darwinian fitness when expressed in the two different sexes may be common in animals and plants. These SA genes should weaken the potential indirect genetic benefits of sexual selection by reducing the fitness of opposite-sex progeny from high-fitness parents. Here we use hemiclonal analysis in the fruit fly, Drosophila melanogaster, to directly measure the inheritance of fitness across generations, over the entire genome. We show that any potential genetic benefits of sexual selection in this system are not merely weakened, but completely reversed over one generation because high-fitness males produce low-fitness daughters and high-fitness mothers produce low-fitness sons. Moreover, male fitness was not inherited by sons, consistent with both theory and recent evidence connecting this form of SA variation with the X chromosome. This inheritance pattern may help to explain how genetic variation for fitness is sustained despite strong sexual selection, and why the ZW sex chromosome system found in birds and butterflies appears to foster the evolution of extreme secondary sexual characters in males. PMID:17105343

  19. Intralocus sexual conflict diminishes the benefits of sexual selection.

    PubMed

    Pischedda, Alison; Chippindale, Adam K

    2006-11-01

    Evolution based on the benefits of acquiring "good genes" in sexual selection is only plausible with the reliable transmission of genetic quality from one generation to the next. Accumulating evidence suggests that sexually antagonistic (SA) genes with opposite effects on Darwinian fitness when expressed in the two different sexes may be common in animals and plants. These SA genes should weaken the potential indirect genetic benefits of sexual selection by reducing the fitness of opposite-sex progeny from high-fitness parents. Here we use hemiclonal analysis in the fruit fly, Drosophila melanogaster, to directly measure the inheritance of fitness across generations, over the entire genome. We show that any potential genetic benefits of sexual selection in this system are not merely weakened, but completely reversed over one generation because high-fitness males produce low-fitness daughters and high-fitness mothers produce low-fitness sons. Moreover, male fitness was not inherited by sons, consistent with both theory and recent evidence connecting this form of SA variation with the X chromosome. This inheritance pattern may help to explain how genetic variation for fitness is sustained despite strong sexual selection, and why the ZW sex chromosome system found in birds and butterflies appears to foster the evolution of extreme secondary sexual characters in males. PMID:17105343

  20. Prenatal programming of sexual partner preference: the ram model.

    PubMed

    Roselli, C E; Stormshak, F

    2009-03-01

    In our laboratory, the domestic ram is used as an experimental model to study the early programming of neural mechanisms underlying same-sex partner preference. This interest developed from the observation that approximately 8% of domestic rams are sexually attracted to other rams (male-oriented) in contrast to the majority of rams that are attracted to oestrous ewes (female-oriented). One prominent feature of sexual differentiation in many species is the presence of a sexually dimorphic nucleus (SDN) in the preoptic/anterior hypothalamus that is larger in males than in females. Lesion studies in rats and ferrets implicate the SDN in the expression of sexual preferences. We discovered an ovine SDN (oSDN) in the preoptic/anterior hypothalamus that is smaller in male- than in female-oriented rams and similar in size to the oSDN of ewes. Neurones of the oSDN show abundant aromatase expression that is also reduced in male-oriented compared to female-oriented rams. This observation suggests that sexual partner preferences are neurologically hard-wired and could be influenced by hormones. Aromatase-containing neurones constitute a nascent oSDN as early as day 60 of gestation, which becomes sexually dimorphic by day 135 of gestation when it is two-fold larger in males than in females. Exposure of fetal female lambs to exogenous testosterone from days 30-90 of gestation resulted in a masculinised oSDN. These data demonstrate that the oSDN develops prenatally and may influence adult sexual preferences. Surprisingly, inhibition of aromatase activity in the brain of ram foetuses during the critical period did not interfere with defeminisation of adult sexual partner preference or oSDN volume. These results fail to support an essential role for neural aromatase in the sexual differentiation of sheep brain and behaviour. Thus, we propose that oSDN morphology and male-typical partner preferences may instead be programmed through an androgen receptor mechanism not involving aromatisation. PMID:19207819

  1. Support for the hypothesis that sexual breast stimulation is an ancestral practice and a key to understanding women's health.

    PubMed

    Robinson, V C

    2015-12-01

    Women's health is seriously impacted by sexual dysfunction, mental depression, breast cancer, and gynecological cancers. Breast feeding has been found to reduce the risk of in-situ cervical cancer, endometrial cancer of the uterus, ovarian cancer, and breast cancer. This protective effect of breast feeding supports the notion that another functional use of the breast, sexual breast stimulation, promoted by women to incite their sexual arousal and orgasm, is a practice which also reduces the risk of these same cancers, and protects against sexual dysfunction and mental depression. The significance of the practice of breast sex or "sexual breast love" lies with its deeply rooted past in the founding of our species, Homo sapiens. No other species exhibits breast sex, a human cultural activity that is implicated in women's desire, sexual satisfaction, and the development of human sociality. For species females as a whole, nipple stimulation by a partner during sex, over the adult life of a female, has occurred since the inception of H. sapiens, so that the failure to engage in this activity is counter to a species typical practice and endangers women's health. Breast sex results in nipple erection, and may micmic the effects of breast feeding, causing an increase of oxytocin in the body. Breast sex is an enriched type of sexuality that enables love between the sexes and the pair bond. The intimacy of breast sex creates a common ground of sexual knowledge, allowing empathy, cooperation, commitment, and communication. It induces reciprocity and therefore happiness. With breast sex, there is an increase of the positive emotions over the chimpanzees, promoting advanced cognition. Research into whether oxytocin release is caused by stimulation of the breasts in non-lactating women is inconclusive, but cultural studies demonstrate that breast stimulation induces sexual arousal, and research has shown that sexual arousal is associated with oxytocin release. PMID:26386486

  2. Computer Simulation of Sexual Selection on Age-Structured Populations

    NASA Astrophysics Data System (ADS)

    Martins, S. G. F.; Penna, T. J. P.

    Using computer simulations of a bit-string model for age-structured populations, we found that sexual selection of older males is advantageous, from an evolutionary point of view. These results are in opposition to a recent proposal of females choosing younger males. Our simulations are based on findings from recent studies of polygynous bird species. Since secondary sex characters are found mostly in males, we could make use of asexual populations that can be implemented in a fast and efficient way.

  3. Sexual shape dimorphism accelerated by male–male competition, but not prevented by sex-indiscriminate parental care in dung beetles (Scarabaeidae)

    PubMed Central

    Kishi, Shigeki; Takakura, Koh-Ichi; Nishida, Takayoshi

    2015-01-01

    Dimorphic sexual differences in shape and body size are called sexual dimorphism and sexual size dimorphism, respectively. The degrees of both dimorphisms are considered to increase with sexual selection, represented by male–male competition. However, the degrees of the two dimorphisms often differ within a species. In some dung beetles, typical sexual shape dimorphisms are seen in male horns and other exaggerated traits, although sexual size dimorphism looks rare. We hypothesized that the evolution of this sexual shape dimorphism without sexual size dimorphism is caused by male–male competition and their crucial and sex-indiscriminate provisioning behaviors, in which parents provide the equivalent size of brood ball with each of both sons and daughters indiscriminately. As a result of individual-based model simulations, we show that parents evolve to provide each of sons and daughters with the optimal amount of resource for a son when parents do not distinguish the sex of offspring and males compete for mates. This result explains why crucial and sex-indiscriminate parental provisioning does not prevent the evolution of sexual shape dimorphism. The model result was supported by empirical data of Scarabaeidae beetles. In some dung beetles, sexual size dimorphism is absent, compared with significant sexual size dimorphism in other horned beetles, although both groups exhibit similar degrees of sexual shape dimorphism in male horns and other exaggerated traits. PMID:26306164

  4. Gender-Based Misconduct Policies for Students (including Sexual Assault, Sexual Harassment Gender-Based

    E-print Network

    Vecer, Jan

    Gender-Based Misconduct Policies for Students (including Sexual Assault, Sexual Harassment Gender for Gender-Based and Sexual Misconduct | August 2013 #12;ii | P a g e Table of Contents Introduction......................................................................................................................... 2 Examples of Gender-Based Misconduct

  5. The association of sexual interest and sexual behaviors among adolescent women: A daily diary perspective

    PubMed Central

    Fortenberry, J. Dennis; Hensel, Devon J.

    2011-01-01

    Theoretical and empirical linkages of adult women’s sexual interest and sexual behaviors are relatively well-established, but few data address similar issues in adolescent women. This paper reviews data from published reports of associations of adolescent women’s sexual interest and various sexual behaviors. All of the papers reported data collected from a single longitudinal cohort of young women. The primary source of data collection was daily diaries, allowing close temporal pairing of sexual interest with sexual behaviors. Young women’s sexual interest on a given day was consistently and independently associated with sexual activity on that day, whether the behavior was first lifetime coitus, coitus, fellatio, cunnilingus, anal intercourse, or coitus during menses. We also found no evidence of influence of hormonal contraceptives on young women’s sexual interest. Taken together, these data demonstrate the relevance of sexual interest as a key factor in young women’s sexuality and sexual behavior. PMID:21397605

  6. The Developmental Association of Sexual Self-Concept with Sexual Behavior among Adolescent Women

    PubMed Central

    Hensel, Devon J.; Fortenberry, J. Dennis; O’Sullivan, Lucia F.; Orr, Donald P.

    2013-01-01

    Developing a sexual self-concept is an important developmental task of adolescence; however, little empirical evidence describes this development, nor how these changes are related to development in sexual behavior. Using longitudinal cohort data from adolescent women, we invoked latent growth curve analysis to: (1) examine reciprocal development in sexual self-concept (sexual openness, sexual esteem and sexual anxiety) over a four year time frame; (2) describe the relationship of these trajectories with changes in sexual behavior. We found significant transactional effects between these dimensions and behavior: sexual self-concept evolved during adolescence in a manner consistent with less reserve, less anxiety and greater personal comfort with sexuality and sexual behavior. Moreover, we found that sexual self-concept results from sexual behavior, as well as regulates future behavior. PMID:20970178

  7. An Interpersonal Investigation of Sexual Self-Schemas.

    PubMed

    Mueller, Kyle; Rehman, Uzma S; Fallis, Erin E; Goodnight, Jackson A

    2016-02-01

    A sexual self-schema is a cognitive generalization about sexual aspects of the self. In the current study, we examined how an individual's sexual self-schema influenced the processing of self and partner related sexual information. Specifically, we investigated how sexual self-schemas related to own and partner sexual satisfaction and how they influenced perceptions of partner sexual satisfaction. Participants were 117 heterosexual couples in committed, long-term relationships. Both partners completed measures assessing their sexual self-schemas, their own sexual satisfaction, and perceptions of partner sexual satisfaction. Consistent with our predictions, own sexual schema was associated with own sexual satisfaction. For men, more positive sexual self-schemas were associated with greater sexual satisfaction, and for women, more negative sexual self-schemas were associated with lower sexual satisfaction. For both men and women, there was no significant association between own sexual self-schema and partner sexual satisfaction. Sexual self-schemas directly and indirectly influenced an individual's perception of the partner's sexual satisfaction, such that men and women with more positive sexual self-schemas rated their partners as more sexually satisfied, after controlling for the partner's self-reported level of sexual satisfaction. Our findings demonstrated that sexual self-schemas are relevant to own sexual satisfaction as well as the processing of interpersonally relevant sexual information, specifically one's perceptions of partner sexual satisfaction. PMID:26545914

  8. Childhood Sexual Abuse and Suicide

    MedlinePLUS

    ... physical and emotional neglect . 2 23456 “Sexual victimization… creates an overwhelming sense of powerlessness , worthlessness , and a felt inability to change or control one’s environment. It creates self-loathing… ...

  9. Caring Community Responding to sexual

    E-print Network

    Caring Community Responding to sexual violence and harassment The Firefighter Humanoid robot earns of Historical Photograph Col- lection, Special Collections, University Libraries, Virginia Tech. The Firefighter to train firefighters. Restaurants of Yesteryear: Nostalgia feeds memories of Blacksburg's eateries

  10. Benchmarking contactless acquisition sensor reproducibility for latent fingerprint trace evidence

    NASA Astrophysics Data System (ADS)

    Hildebrandt, Mario; Dittmann, Jana

    2015-03-01

    Optical, nano-meter range, contactless, non-destructive sensor devices are promising acquisition techniques in crime scene trace forensics, e.g. for digitizing latent fingerprint traces. Before new approaches are introduced in crime investigations, innovations need to be positively tested and quality ensured. In this paper we investigate sensor reproducibility by studying different scans from four sensors: two chromatic white light sensors (CWL600/CWL1mm), one confocal laser scanning microscope, and one NIR/VIS/UV reflection spectrometer. Firstly, we perform an intra-sensor reproducibility testing for CWL600 with a privacy conform test set of artificial-sweat printed, computer generated fingerprints. We use 24 different fingerprint patterns as original samples (printing samples/templates) for printing with artificial sweat (physical trace samples) and their acquisition with contactless sensory resulting in 96 sensor images, called scan or acquired samples. The second test set for inter-sensor reproducibility assessment consists of the first three patterns from the first test set, acquired in two consecutive scans using each device. We suggest using a simple feature space set in spatial and frequency domain known from signal processing and test its suitability for six different classifiers classifying scan data into small differences (reproducible) and large differences (non-reproducible). Furthermore, we suggest comparing the classification results with biometric verification scores (calculated with NBIS, with threshold of 40) as biometric reproducibility score. The Bagging classifier is nearly for all cases the most reliable classifier in our experiments and the results are also confirmed with the biometric matching rates.

  11. Child sexual abuse, links to later sexual exploitation/high-risk sexual behavior, and prevention/treatment programs.

    PubMed

    Lalor, Kevin; McElvaney, Rosaleen

    2010-10-01

    This paper reviews the literature on the nature and incidence of child sexual abuse, explores the link between child sexual abuse and later sexual exploitation, and reviews the literature on prevention strategies and effective interventions in child sexual abuse services. Our understanding of the international epidemiology of child sexual abuse is considerably greater than it was just 10 years ago, and studies from around the world are examined. Childhood sexual abuse can involve a wide number of psychological sequelae, including low self-esteem, anxiety, and depression. Numerous studies have noted that child sexual abuse victims are vulnerable to later sexual revictimization, as well as the link between child sexual abuse and later engagement in high-risk sexual behaviour. Survivors of child sexual abuse are more likely to have multiple sex partners, become pregnant as teenagers, and experience sexual assault as adults. Various models which attempt to account for this inter-relationship are presented; most invoke mediating variables such as low self-esteem, drug/alcohol use, PTSD and distorted sexual development. Prevention strategies for child sexual abuse are examined including media campaigns, school-based prevention programmes, and therapy with abusers. The results of a number of meta-analyses are examined. However, researchers have identified significant methodological limitations in the extant research literature that impede the making of recommendations for implementing existing therapeutic programmes unreservedly. PMID:20679329

  12. Inferences on mating and sexual systems of two Pacific Cinetorhynchus shrimps (Decapoda, Rhynchocinetidae) based on sexual dimorphism in body size and cheliped weaponry

    PubMed Central

    Bauer, Raymond T.; Okuno, Junji; Thiel, Martin

    2014-01-01

    Abstract Sexual dimorphism in body size and weaponry was examined in two Cinetorhynchus shrimp species in order to formulate hypotheses on their sexual and mating systems. Collections of Cinetorhynchus sp. A and Cinetorhynchus sp. B were made in March, 2011 on Coconut Island, Hawaii, by hand dipnetting and minnow traps in coral rubble bottom in shallow water. Although there is overlap in male and female size, some males are much larger than females. The major (pereopod 1) chelipeds of males are significantly larger and longer than those of females. In these two Cinetorhynchus species, males and females have third maxillipeds of similar relative size, i.e., those of males are not hypertrophied and probably not used as spear-like weapons as in some other rhynchocinetid (Rhynchocinetes) species. Major chelae of males vary with size, changing from typical female-like chelae tipped with black corneous stout setae to subchelate or prehensile appendages in larger males. Puncture wounds or regenerating major chelipeds were observed in 26.1 % of males examined (N = 38 including both species). We interpret this evidence on sexual dimorphism as an indication of a temporary male mate guarding or “neighborhoods of dominance” mating system, in which larger dominant robustus males defend females and have greater mating success than smaller males. Fecundity of females increased with female size, as in most caridean species (500–800 in Cinetorhynchus sp. A; 300–3800 in Cinetorhynchus sp. B). Based on the sample examined, we conclude that these two species have a gonochoric sexual system (separate sexes) like most but not all other rhynchocinetid species in which the sexual system has been investigated. PMID:25561837

  13. Inferences on mating and sexual systems of two Pacific Cinetorhynchus shrimps (Decapoda, Rhynchocinetidae) based on sexual dimorphism in body size and cheliped weaponry.

    PubMed

    Bauer, Raymond T; Okuno, Junji; Thiel, Martin

    2014-01-01

    Sexual dimorphism in body size and weaponry was examined in two Cinetorhynchus shrimp species in order to formulate hypotheses on their sexual and mating systems. Collections of Cinetorhynchus sp. A and Cinetorhynchus sp. B were made in March, 2011 on Coconut Island, Hawaii, by hand dipnetting and minnow traps in coral rubble bottom in shallow water. Although there is overlap in male and female size, some males are much larger than females. The major (pereopod 1) chelipeds of males are significantly larger and longer than those of females. In these two Cinetorhynchus species, males and females have third maxillipeds of similar relative size, i.e., those of males are not hypertrophied and probably not used as spear-like weapons as in some other rhynchocinetid (Rhynchocinetes) species. Major chelae of males vary with size, changing from typical female-like chelae tipped with black corneous stout setae to subchelate or prehensile appendages in larger males. Puncture wounds or regenerating major chelipeds were observed in 26.1 % of males examined (N = 38 including both species). We interpret this evidence on sexual dimorphism as an indication of a temporary male mate guarding or "neighborhoods of dominance" mating system, in which larger dominant robustus males defend females and have greater mating success than smaller males. Fecundity of females increased with female size, as in most caridean species (500-800 in Cinetorhynchus sp. A; 300-3800 in Cinetorhynchus sp. B). Based on the sample examined, we conclude that these two species have a gonochoric sexual system (separate sexes) like most but not all other rhynchocinetid species in which the sexual system has been investigated. PMID:25561837

  14. Flying in tune: sexual recognition in mosquitoes.

    PubMed

    Gibson, Gabriella; Russell, Ian

    2006-07-11

    Mosquitoes hear with their antennae, which in most species are sexually dimorphic. Johnston, who discovered the mosquito auditory organ at the base of the antenna 150 years ago, speculated that audition was involved with mating behaviour. Indeed, male mosquitoes are attracted to female flight tones. The male auditory organ has been proposed to act as an acoustic filter for female flight tones, but female auditory behavior is unknown. We show, for the first time, interactive auditory behavior between males and females that leads to sexual recognition. Individual males and females both respond to pure tones by altering wing-beat frequency. Behavioral auditory tuning curves, based on minimum threshold sound levels that elicit a change in wing-beat frequency to pure tones, are sharper than the mechanical tuning of the antennae, with males being more sensitive than females. We flew opposite-sex pairs of tethered Toxorhynchites brevipalpis and found that each mosquito alters its wing-beat frequency in response to the flight tone of the other, so that within seconds their flight-tone frequencies are closely matched, if not completely synchronized. The flight tones of same-sex pairs may converge in frequency but eventually diverge dramatically. PMID:16824918

  15. Gravity as field - field oriented framework reproducing General Relativity

    E-print Network

    Piotr Ogonowski; Piotr Skindzier

    2015-09-21

    In the last article we have created foundations for gravitational field oriented framework (DaF) that reproduces GR. In this article we show, that using DaF approach, we can reproduce Schwarzschild solution with orbit equations, effective potential and constants of motion. Next we generalize results to other GR solutions and show, how gravitational field affects spacetime curvature and intrinsic spin of the bodies. It also appears, that field oriented approach requests to assign some spin value to the massless particles. Derived DaF framework has therefore significant meaning for searching for field based interpretation of gravity requested by quantum gravity.

  16. Sexual Dimorphism in Bite Performance Drives Morphological Variation in Chameleons

    PubMed Central

    da Silva, Jessica M.; Herrel, Anthony; Measey, G. John; Tolley, Krystal A.

    2014-01-01

    Phenotypic performance in different environments is central to understanding the evolutionary and ecological processes that drive adaptive divergence and, ultimately, speciation. Because habitat structure can affect an animal’s foraging behaviour, anti-predator defences, and communication behaviour, it can influence both natural and sexual selection pressures. These selective pressures, in turn, act upon morphological traits to maximize an animal’s performance. For performance traits involved in both social and ecological activities, such as bite force, natural and sexual selection often interact in complex ways, providing an opportunity to understand the adaptive significance of morphological variation with respect to habitat. Dwarf chameleons within the Bradypodion melanocephalum-Bradypodion thamnobates species complex have multiple phenotypic forms, each with a specific head morphology that could reflect its use of either open- or closed-canopy habitats. To determine whether these morphological differences represent adaptations to their habitats, we tested for differences in both absolute and relative bite performance. Only absolute differences were found between forms, with the closed-canopy forms biting harder than their open-canopy counterparts. In contrast, sexual dimorphism was found for both absolute and relative bite force, but the relative differences were limited to the closed-canopy forms. These results indicate that both natural and sexual selection are acting within both habitat types, but to varying degrees. Sexual selection seems to be the predominant force within the closed-canopy habitats, which are more protected from aerial predators, enabling chameleons to invest more in ornamentation for communication. In contrast, natural selection is likely to be the predominant force in the open-canopy habitats, inhibiting the development of conspicuous secondary sexual characteristics and, ultimately, enforcing their overall diminutive body size and constraining performance. PMID:24475183

  17. Sexual dimorphism in bite performance drives morphological variation in chameleons.

    PubMed

    da Silva, Jessica M; Herrel, Anthony; Measey, G John; Tolley, Krystal A

    2014-01-01

    Phenotypic performance in different environments is central to understanding the evolutionary and ecological processes that drive adaptive divergence and, ultimately, speciation. Because habitat structure can affect an animal's foraging behaviour, anti-predator defences, and communication behaviour, it can influence both natural and sexual selection pressures. These selective pressures, in turn, act upon morphological traits to maximize an animal's performance. For performance traits involved in both social and ecological activities, such as bite force, natural and sexual selection often interact in complex ways, providing an opportunity to understand the adaptive significance of morphological variation with respect to habitat. Dwarf chameleons within the Bradypodion melanocephalum-Bradypodion thamnobates species complex have multiple phenotypic forms, each with a specific head morphology that could reflect its use of either open- or closed-canopy habitats. To determine whether these morphological differences represent adaptations to their habitats, we tested for differences in both absolute and relative bite performance. Only absolute differences were found between forms, with the closed-canopy forms biting harder than their open-canopy counterparts. In contrast, sexual dimorphism was found for both absolute and relative bite force, but the relative differences were limited to the closed-canopy forms. These results indicate that both natural and sexual selection are acting within both habitat types, but to varying degrees. Sexual selection seems to be the predominant force within the closed-canopy habitats, which are more protected from aerial predators, enabling chameleons to invest more in ornamentation for communication. In contrast, natural selection is likely to be the predominant force in the open-canopy habitats, inhibiting the development of conspicuous secondary sexual characteristics and, ultimately, enforcing their overall diminutive body size and constraining performance. PMID:24475183

  18. Sexual activities of Malaysian adolescents.

    PubMed

    Zulkifli, S N; Low, W Y; Yusof, K

    1995-03-01

    This paper examines data on the sexual activities of 1,200 Malaysian adolescents aged 15-21 years based on a probability household sampled survey carried out in Kuala Lumpur in 1986. Sexual behaviours like premarital sexual intercourse, contraceptive usage and masturbation were presented. Of the 1,181 unmarried respondents, 9% (105) reported having had sexual intercourse; males were significantly more experienced compared to females. Older age groups were also found to be more sexually active than the younger ones. Among those who had experience dating (n = 521), 20% (105) have experienced sexual intercourse, 44% (228) have kissed and necked, and 35% (183) have experienced petting, while 24% (130) have had no physical intimacies. Poor use of contraception was also revealed. The most commonly used were condoms, oral contraceptives and withdrawal. With regard to masturbation, males begin this practice relatively earlier than females. Almost half of those who indulged in masturbation were worried by the act, especially the females. Implications of the findings are discussed. PMID:7752975

  19. Pathologizing sexual deviance: a history.

    PubMed

    De Block, Andreas; Adriaens, Pieter R

    2013-01-01

    This article provides a historical perspective on how both American and European psychiatrists have conceptualized and categorized sexual deviance throughout the past 150 years. During this time, quite a number of sexual preferences, desires, and behaviors have been pathologized and depathologized at will, thus revealing psychiatry's constant struggle to distinguish mental disorder--in other words, the "perversions," "sexual deviations," or "paraphilias"--from immoral, unethical, or illegal behavior. This struggle is apparent in the works of 19th- and early-20th-century psychiatrists and sexologists, but it is also present in the more recent psychiatric textbooks and diagnostic manuals, such as the consecutive editions of the Diagnostic and Statistical Manual of Mental Disorders (DSM). While much of the historical literature revolves around the controversy over homosexuality, this article also reviews the recent medicohistorical and sociohistorical work on other forms of sexual deviance, including the diagnostic categories listed in the latest edition, the DSM-IV-TR: exhibitionism, voyeurism, fetishism, frotteurism, pedophilia, sexual masochism, sexual sadism, and transvestic fetishism. PMID:23480073

  20. Specificity of sexual arousal for sexual activities in men and women with conventional and masochistic sexual interests.

    PubMed

    Chivers, Meredith L; Roy, Carolyn; Grimbos, Teresa; Cantor, James M; Seto, Michael C

    2014-07-01

    Prior studies consistently report that men's genital responses correspond to their sexual activity interests (consenting vs. coercive sex) whereas women's responses do not. For women, however, these results may be confounded by the sexual activities studied and lack of suitable controls. We examined the subjective and genital arousal responses of men and women with conventional (22 men and 15 women) or masochistic sexual interests (16 men and 17 women) to narratives describing conventional sex or masochistic sex. The aims of the studies were twofold: (1) to examine whether gender differences in the specificity of sexual arousal previously observed for gender also exist for sexual activity interests; and (2) to examine whether men and women with masochistic sexual interests demonstrate specificity of sexual response for their preferred sexual activities. Surprisingly, the pattern of results was very similar for men and women. Both men and women with conventional sexual interests (WCI) reported more sexual arousal, and responded more genitally, to conventional than to masochistic sex, demonstrating specificity of sexual arousal for their preferred sexual activities. Despite showing specificity for conventional sexual activities, the genital responses of WCI were still gender nonspecific. In contrast, women and men with masochistic sexual interests demonstrated nonspecific subjective and genital responses to conventional and masochistic sex. Indices of genital and subjective sexual arousal to masochistic versus conventional stimuli were positively and significantly correlated with self-reported thoughts, fantasies, interests, and behaviors involving masochism. The results suggest that gender similarities in the specificity of sexual arousal for sexual activity exist despite consistent gender differences in the specificity of sexual arousal for gender. PMID:24057208

  1. High lability of sexual system over 250 million years of evolution in morphologically conservative tadpole shrimps

    PubMed Central

    2013-01-01

    Background Sexual system is a key factor affecting the genetic diversity, population structure, genome structure and the evolutionary potential of species. The sexual system androdioecy – where males and hermaphrodites coexist in populations – is extremely rare, yet is found in three crustacean groups, barnacles, a genus of clam shrimps Eulimnadia, and in the order Notostraca, the tadpole shrimps. In the ancient crustacean order Notostraca, high morphological conservatism contrasts with a wide diversity of sexual systems, including androdioecy. An understanding of the evolution of sexual systems in this group has been hampered by poor phylogenetic resolution and confounded by the widespread occurrence of cryptic species. Here we use a multigene supermatrix for 30 taxa to produce a comprehensive phylogenetic reconstruction of Notostraca. Based on this phylogenetic reconstruction we use character mapping techniques to investigate the evolution of sexual systems. We also tested the hypothesis that reproductive assurance has driven the evolution of androdioecy in Notostraca. Results Character mapping analysis showed that sexual system is an extremely flexible trait within Notostraca, with repeated shifts between gonochorism and androdioecy, the latter having evolved a minimum of five times. In agreement with the reproductive assurance hypothesis androdioecious notostracans are found at significantly higher latitudes than gonochoric ones indicating that post glacial re-colonisation may have selected for the higher colonisation ability conferred by androdioecy. Conclusions In contrast to their conserved morphology, sexual system in Notostraca is highly labile and the rare reproductive mode androdioecy has evolved repeatedly within the order. Furthermore, we conclude that this lability of sexual system has been maintained for at least 250 million years and may have contributed to the long term evolutionary persistence of Notostraca. Our results further our understanding of the evolution of androdioecy and indicate that reproductive assurance is a recurrent theme involved in the evolution of this sexual system. PMID:23384124

  2. Sexual Dimorphisms of Appendicular Musculoskeletal Morphology Related to Social Displayin Cuban Anolis Lizards.

    PubMed

    Anzai, Wataru; Cádiz, Antonio; Endo, Hideki

    2015-10-01

    In Anolis lizards, sexual dimorphism has been reported in morphological and ecological traits. Males show larger body size and longer limbs related to territorial combat and courtship display with the dewlap. Although functional-anatomical traits are closely related to locomotor behaviors, differences between sexes in musculoskeletal traits on limbs remain unclear. We explored the relationships among sexual dimorphisms in musculoskeletal morphology, habitat, and locomotor traits in Anolis lizards. Specifically, we examined appendicular musculoskeletal morphology in three species of Cuban Anolis by measuring muscle mass and lengths of moment arms. Through comparisons of crossing locomotion, we found that the runner species possessed larger extensors in hindlimbs, which are advantageous for running, whereas the masses of the humeral and femoral retractors were larger in climber species, allowing these lizards to hold up their bodies and occupy tree substrates. Comparisons between the sexes showed different trends among the three species. Males of A. porcatus, which inhabit narrow branches or leaves, had stronger elbow extensors that maintain the display posture. In contrast, males of A. sagrei, which occupy broad surfaces, did not show sexual differences that affected social display. Moreover, A. bartschi indicated sexual differences despite the absence of dewlapping behavior. Our findings suggest that both sexes show fundamentally similar relationships between muscular morphology and locomotor habits to adapt arboreal or terrestrial substrates, and yet sexual dimorphism in forelimb muscles may additionally affected by male specific display with the dewlap. PMID:26428721

  3. Female mate preferences for male body size and shape promote sexual isolation in threespine sticklebacks

    PubMed Central

    Head, Megan L; Kozak, Genevieve M; Boughman, Janette W

    2013-01-01

    Female mate preferences for ecologically relevant traits may enhance natural selection, leading to rapid divergence. They may also forge a link between mate choice within species and sexual isolation between species. Here, we examine female mate preference for two ecologically important traits: body size and body shape. We measured female preferences within and between species of benthic, limnetic, and anadromous threespine sticklebacks (Gasterosteus aculeatus species complex). We found that mate preferences differed between species and between contexts (i.e., within vs. between species). Within species, anadromous females preferred males that were deep bodied for their size, benthic females preferred larger males (as measured by centroid size), and limnetic females preferred males that were more limnetic shaped. In heterospecific mating trials between benthics and limnetics, limnetic females continued to prefer males that were more limnetic like in shape when presented with benthic males. Benthic females showed no preferences for size when presented with limnetic males. These results show that females use ecologically relevant traits to select mates in all three species and that female preference has diverged between species. These results suggest that sexual selection may act in concert with natural selection on stickleback size and shape. Further, our results suggest that female preferences may track adaptation to local environments and contribute to sexual isolation between benthic and limnetic sticklebacks. PMID:23919161

  4. The evolution of obligate sex: the roles of sexual selection and recombination.

    PubMed

    Kleiman, Maya; Hadany, Lilach

    2015-07-01

    The evolution of sex is one of the greatest mysteries in evolutionary biology. An even greater mystery is the evolution of obligate sex, particularly when competing with facultative sex and not with complete asexuality. Here, we develop a stochastic simulation of an obligate allele invading a facultative population, where males are subject to sexual selection. We identify a range of parameters where sexual selection can contribute to the evolution of obligate sex: Especially when the cost of sex is low, mutation rate is high, and the facultative individuals do not reproduce sexually very often. The advantage of obligate sex becomes larger in the absence of recombination. Surprisingly, obligate sex can take over even when the population has a lower mean fitness as a result. We show that this is due to the high success of obligate males that can compensate the cost of sex. PMID:26257871

  5. 6 Cosmological and Biological Reproducibility: Limits on the Maximum Entropy

    E-print Network

    Lineweaver, Charles H.

    of the uni- verse, many of the same structures (planets, stars, galaxies) would be reproduced as the universe of Maximum Entropy Production (also De- war, this volume). Dewar points out that our ignorance can, the same constants, forces and the same expansion. The universe begins again hot and dense

  6. METHODOLOGY ARTICLE Open Access A simple and reproducible breast cancer

    E-print Network

    Geman, Donald

    METHODOLOGY ARTICLE Open Access A simple and reproducible breast cancer prognostic test Luigi test for breast cancer based on a 70-gene expression signature. We provide all the software, Personalized medicine, Breast cancer, MammaPrint Background Currently, a number of molecular-based prognostic

  7. Palm Vein Database and Experimental Framework for Reproducible Research

    E-print Network

    Palm Vein Database and Experimental Framework for Reproducible Research Pedro Tome and S.tome, sebastien.marcel}@idiap.ch Abstract: A palm vein database acquired by a contactless sensor together vein recognition system uses automatic palm region segmentation and circu- lar Gabor filter approach

  8. Trust, but Replicate: Evidence, Authority, Reproducibility, and the Scientific Method

    E-print Network

    Stark, Philip B.

    Trust, but Replicate: Evidence, Authority, Reproducibility, and the Scientific Method Philip B research have largely abandoned the scientific method, and now rely more on trusting authority than without evidence are not Science. Bring back Science We've traded the Scientific Method for "trust me!" We

  9. Latin America Today: An Atlas of Reproducible Pages. Revised Edition.

    ERIC Educational Resources Information Center

    World Eagle, Inc., Wellesley, MA.

    This document contains reproducible maps, charts and graphs of Latin America for use by teachers and students. The maps are divided into five categories (1) the land; (2) peoples, countries, cities, and governments; (3) the national economies, product, trade, agriculture, and resources; (4) energy, education, employment, illicit drugs, consumer…

  10. ReproPhylo: An Environment for Reproducible Phylogenomics

    PubMed Central

    Szitenberg, Amir; John, Max; Blaxter, Mark L.; Lunt, David H.

    2015-01-01

    The reproducibility of experiments is key to the scientific process, and particularly necessary for accurate reporting of analyses in data-rich fields such as phylogenomics. We present ReproPhylo, a phylogenomic analysis environment developed to ensure experimental reproducibility, to facilitate the handling of large-scale data, and to assist methodological experimentation. Reproducibility, and instantaneous repeatability, is built in to the ReproPhylo system and does not require user intervention or configuration because it stores the experimental workflow as a single, serialized Python object containing explicit provenance and environment information. This ‘single file’ approach ensures the persistence of provenance across iterations of the analysis, with changes automatically managed by the version control program Git. This file, along with a Git repository, are the primary reproducibility outputs of the program. In addition, ReproPhylo produces an extensive human-readable report and generates a comprehensive experimental archive file, both of which are suitable for submission with publications. The system facilitates thorough experimental exploration of both parameters and data. ReproPhylo is a platform independent CC0 Python module and is easily installed as a Docker image or a WinPython self-sufficient package, with a Jupyter Notebook GUI, or as a slimmer version in a Galaxy distribution. PMID:26335558

  11. Darwinian Definition of Life Self-sustaining and reproducing

    E-print Network

    Walter, Frederick M.

    Evolution #12;Darwinian Definition of Life ·Self-sustaining and reproducing ·Capable of evolving] can damage DNA ­ solar UV-a [ Definitions 1 Becquerel (Bq) = 1. Microbes also share genetic material. #12;Genetic Diversity A population carries lots of diverse traits

  12. Reproducibility of Tactile Assessments for Children with Unilateral Cerebral Palsy

    ERIC Educational Resources Information Center

    Auld, Megan Louise; Ware, Robert S.; Boyd, Roslyn Nancy; Moseley, G. Lorimer; Johnston, Leanne Marie

    2012-01-01

    A systematic review identified tactile assessments used in children with cerebral palsy (CP), but their reproducibility is unknown. Sixteen children with unilateral CP and 31 typically developing children (TDC) were assessed 2-4 weeks apart. Test-retest percent agreements within one point for children with unilateral CP (and TDC) were…

  13. The United States Today: An Atlas of Reproducible Pages.

    ERIC Educational Resources Information Center

    World Eagle, Inc., Wellesley, MA.

    Black and white maps, graphs and tables that may be reproduced are presented in this volume focusing on the United States. Some of the features of the United States depicted are: size, population, agriculture and resources, manufactures, trade, citizenship, employment, income, poverty, the federal budget, energy, health, education, crime, and the…

  14. ReproPhylo: An Environment for Reproducible Phylogenomics.

    PubMed

    Szitenberg, Amir; John, Max; Blaxter, Mark L; Lunt, David H

    2015-09-01

    The reproducibility of experiments is key to the scientific process, and particularly necessary for accurate reporting of analyses in data-rich fields such as phylogenomics. We present ReproPhylo, a phylogenomic analysis environment developed to ensure experimental reproducibility, to facilitate the handling of large-scale data, and to assist methodological experimentation. Reproducibility, and instantaneous repeatability, is built in to the ReproPhylo system and does not require user intervention or configuration because it stores the experimental workflow as a single, serialized Python object containing explicit provenance and environment information. This 'single file' approach ensures the persistence of provenance across iterations of the analysis, with changes automatically managed by the version control program Git. This file, along with a Git repository, are the primary reproducibility outputs of the program. In addition, ReproPhylo produces an extensive human-readable report and generates a comprehensive experimental archive file, both of which are suitable for submission with publications. The system facilitates thorough experimental exploration of both parameters and data. ReproPhylo is a platform independent CC0 Python module and is easily installed as a Docker image or a WinPython self-sufficient package, with a Jupyter Notebook GUI, or as a slimmer version in a Galaxy distribution. PMID:26335558

  15. Reproducibility of atopy patch tests with food and inhalant allergens.

    PubMed

    Ronchetti, R; Jesenak, M; Barberi, S; Ronchetti, F; Rennerova, Z; Trubacova, D; Villa, M P

    2008-01-01

    Although atopy patch tests (APT) seem a valuable additional tool in the diagnostic work-up for food allergy in children with atopic eczema/dermatitis syndrome, the immunopathology and some technical aspects of testing remain controversial. Few published data are available on the reproducibility of APT with inhalants and only two studies include fresh food allergens. In this study we therefore investigated the reproducibility of duplicate APT (left versus right side of the back) with native and commercially available food (cow s milk, hen s egg, tomato, wheat flour) and with inhalant allergens (Dermatophagoides pteronyssinus and mixed grasses) in a large unselected population of children. We tested a population of 277 Italian school children with three APT allergens: fresh food (cow s milk, hen s egg, tomato and wheat flour), standardised food allergens in petrolatum (the same four foods) and standardised inhalant allergens routinely used for skin prick testing. For the four food allergens (applied in the natural form or as the standardised commercial preparation) from one- to three quarters of the APT gave positive results on one side and negative reactions on the opposite side (Cohen s K coefficient between 0.38, fresh tomato and 0.81, fresh cow s milk). Conversely, APT with inhalant allergens were invariably reproducible (Cohen s K = 1.00). The possible technical and immunologic reasons explaining why reproducibility of APT differed for the two types of allergens await an answer from extensive controlled studies. PMID:18394315

  16. Reeve-Irvine Research Center Replication and Reproducibility in

    E-print Network

    with a minimum of variability in surgery, animal care, outcome evaluation and cellular analyses, Promptly report the methodology and results. The desired result is that, if proven to provide reliable and robust benefit, clinical testing. If studies are NOT reproducible, this could save $millions that would otherwise be spent

  17. Sexual selection: Another Darwinian process.

    PubMed

    Gayon, Jean

    2010-02-01

    Why was sexual selection so important to Darwin? And why was it de-emphasized by almost all of Darwin's followers until the second half of the 20th century? These two questions shed light on the complexity of the scientific tradition named "Darwinism". Darwin's interest in sexual selection was almost as old as his discovery of the principle of natural selection. From the beginning, sexual selection was just another "natural means of selection", although different from standard "natural selection" in its mechanism. But it took Darwin 30 years to fully develop his theory, from the early notebooks to the 1871 book The Descent of Man, and Selection in Relation to Sex. Although there is a remarkable continuity in his basic ideas about sexual selection, he emphasized increasingly the idea that sexual selection could oppose the action of natural selection and be non adaptive. In time, he also gave more weight to mate choice (especially female choice), giving explicit arguments in favor of psychological notions such as "choice" and "aesthetic sense". But he also argued that there was no strict demarcation line between natural and sexual selection, a major difficulty of the theory from the beginning. Female choice was the main reason why Alfred Russel Wallace, the co-discoverer of the principle of natural selection, engaged in a major controversy with Darwin about sexual selection. Wallace was suspicious about sexual selection in general, trying to minimize it by all sorts of arguments. And he denied entirely the existence of female choice, because he thought that it was both unnecessary and an anthropomorphic notion. This had something to do with his spiritualist convictions, but also with his conception of natural selection as a sufficient principle for the evolutionary explanation of all biological phenomena (except for the origin of mind). This is why Wallace proposed to redefine Darwinism in a way that excluded Darwin's principle of sexual selection. The main result of the Darwin-Wallace controversy was that most Darwinian biologists avoided the subject of sexual selection until at least the 1950s, Ronald Fisher being a major exception. This controversy still deserves attention from modern evolutionary biologists, because the modern approach inherits from both Darwin and Wallace. The modern approach tends to present sexual selection as a special aspect of the theory of natural selection, although it also recognizes the big difficulties resulting from the inevitable interaction between these two natural processes of selection. And contra Wallace, it considers mate choice as a major process that deserves a proper evolutionary treatment. The paper's conclusion explains why sexual selection can be taken as a test case for a proper assessment of "Darwinism" as a scientific tradition. Darwin's and Wallace's attitudes towards sexual selection reveal two different interpretations of the principle of natural selection: Wallace's had an environmentalist conception of natural selection, whereas Darwin was primarily sensitive to the element of competition involved in the intimate mechanism of any natural process of selection. Sexual selection, which can lack adaptive significance, reveals this exemplarily. PMID:20338530

  18. The role of sexual self-schema in a diathesis–stress model of sexual dysfunction

    PubMed Central

    CYRANOWSKI, JILL M.; AARESTAD, SUSAN L.; ANDERSEN, BARBARA L.

    2009-01-01

    Sexual self-schemas are cognitive generalizations regarding sexual aspects of the self that represent a core component of one’s sexuality. We contend that individual differences in the sexual self-view represent an important cognitive diathesis for predicting sexual difficulty or dysfunction. We illustrate the role of sexual self-schemas on sexual behavior and responsiveness in healthy female and male samples. Next, we describe how diathesis–stress models of psychopathology have been applied to the sexual arena, and discuss the critical features of clinically useful diathesis variables. Drawing from these criteria, we examine the diathetic properties of sexual self-schemas. Finally, we discuss an empirical test of the proposed diathesis–stress interaction, reviewing the role of women’s sexual self-views on sexual morbidity following diagnosis and treatment for gynecologic cancer. PMID:19587834

  19. Testing cognitive predictors of individual differences in the sexual psychophysiological responses of sexually functional women.

    PubMed

    Clifton, Jessica; Seehuus, Martin; Rellini, Alessandra H

    2015-07-01

    The literature on sexual responses shows a large and not fully understood between-women variance in sexual responses and in strength of coherence between physiological and subjective sexual responses. This study investigated cognitive factors theorized to be associated with sexual responses that could explain such variance. Specifically, we investigated the predictive value of sexual excitation/inhibition and sexual schemas on sexual response and coherence. Vaginal photoplethysmography and continuous subjective sexual arousal were collected from 29 young women while they watched a control/erotic video sequence. Hierarchical linear modeling revealed that high sexual excitation and schemas related to passion and romance were related to higher coherence. These findings support the notion that cognitive factors that enhance sexual arousal contribute to the large variation seen in the coherence of sexual response as measured in the laboratory. PMID:25816911

  20. Intralocus sexual conflict for fitness: sexually antagonistic alleles for testosterone

    PubMed Central

    Mills, Suzanne C.; Koskela, Esa; Mappes, Tapio

    2012-01-01

    Intralocus sexual conflict occurs when a trait encoded by the same genetic locus in the two sexes has different optima in males and females. Such conflict is widespread across taxa, however, the shared phenotypic traits that mediate the conflict are largely unknown. We examined whether the sex hormone, testosterone (T), that controls sexual differentiation, contributes to sexually antagonistic fitness variation in the bank vole, Myodes glareolus. We compared (opposite-sex) sibling reproductive fitness in the bank vole after creating divergent selection lines for T. This study shows that selection for T was differentially associated with son versus daughter reproductive success, causing a negative correlation in fitness between full siblings. Our results demonstrate the presence of intralocus sexual conflict for fitness in this small mammal and that sexually antagonistic selection is acting on T. We also found a negative correlation in fitness between parents and their opposite-sex progeny (e.g. father–daughter), highlighting a dilemma for females, as the indirect genetic benefits of selecting reproductively successful males (high T) are lost with daughters. We discuss mechanisms that may mitigate this disparity between progeny quality. PMID:22171083