Sample records for sexually reproducing species

  1. The hawk-dove game in a sexually reproducing species explains a colourful polymorphism of an endangered bird.

    PubMed

    Kokko, Hanna; Griffith, Simon C; Pryke, Sarah R

    2014-10-22

    The hawk-dove game famously introduced strategic game theory thinking into biology and forms the basis of arguments for limited aggression in animal populations. However, aggressive 'hawks' and peaceful 'doves', with strategies inherited in a discrete manner, have never been documented in a real animal population. Thus, the applicability of game-theoretic arguments to real populations might be contested. Here, we show that the head-colour polymorphism of red and black Gouldian finches (Erythrura gouldiae) provides a real-life example. The aggressive red morph is behaviourally dominant and successfully invades black populations, but when red 'hawks' become too common, their fitness is severely compromised (via decreased parental ability). We also investigate the effects of real-life deviations, particularly sexual reproduction, from the simple original game, which assumed asexual reproduction. A protected polymorphism requires mate choice to be sufficiently assortative. Assortative mating is adaptive for individuals because of genetic incompatibilities affecting hybrid offspring fitness, but by allowing red 'hawks' to persist, it also leads to significantly reduced population sizes. Because reductions in male contributions to parental care are generally known to lead to lower population productivity in birds, we expect zero-sum competition to often have wide ranging population consequences. PMID:25209943

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

    PubMed Central

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

    2012-01-01

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

  3. Laboratory synthesis of an independently reproducing vertebrate species

    PubMed Central

    Lutes, Aracely A.; Baumann, Diana P.; Neaves, William B.; Baumann, Peter

    2011-01-01

    Speciation in animals commonly involves an extrinsic barrier to genetic exchange followed by the accumulation of sufficient genetic variation to impede subsequent productive interbreeding. All-female species of whiptail lizards, which originated by interspecific hybridization between sexual progenitors, are an exception to this rule. Here, the arising species instantaneously acquires a novel genotype combining distinctive alleles from two different species, and reproduction by parthenogenesis constitutes an effective intrinsic barrier to genetic exchange. Fertilization of diploid parthenogenetic females by males of sexual species has produced several triploid species, but these instantaneous speciation events have neither been observed in nature nor have they been reconstituted in the laboratory. Here we report the generation of four self-sustaining clonal lineages of a tetraploid species resulting from fertilization of triploid oocytes from a parthenogenetic Aspidoscelis exsanguis with haploid sperm from Aspidoscelis inornata. Molecular and cytological analysis confirmed the genetic identity of the hybrids and revealed that the females retain the capability of parthenogenetic reproduction characteristic of their triploid mothers. The tetraploid females have established self-perpetuating clonal lineages which are now in the third generation. Our results confirm the hypothesis that secondary hybridization events can lead to asexual lineages of increased ploidy when favorable combinations of parental genomes are assembled. We anticipate that these animals will be a critical tool in understanding the mechanisms underlying the origin and subsequent evolution of asexual amniotes. PMID:21543715

  4. Sexual reproduction in the invasive species Fallopia japonica (Polygonaceae)

    Microsoft Academic Search

    JENNIFER FORMAN; R. V. Kesseli

    2003-01-01

    Fallopia japonica (Polygonaceae) is an invasive perennial plant, well known in North America for its ability to spread aggressively via vegetative reproduction. The contribution of sexual reproduction to the distribution of this species is not well documented, and as a result, F. japonica is treated solely as a clonal species. To investigate the role of sexual reproduction in this species,

  5. Sexual Dimorphism in the Sceloporus undulatus Species Complex 

    E-print Network

    Dittmer, Drew

    2012-10-19

    of the S. undulatus complex.................................................... 13 2 Scatter plot of PC2 and PC3 including both sexes and 4 species analyzed 15 3 Individual specimens of S. consobrinus, S. cowlesi and S. tristichus were classified... to explain sexual dimorphism. Three patterns of sexual dimorphism are commonly observed. The first and often easiest to observe is the asymmetry in size between sexes or sexual size dimorphism (SSD). The second is the presence of weapons such as antlers...

  6. 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

  7. 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

  8. Disentangling precopulatory and postcopulatory sexual selection in polyandrous species.

    PubMed

    Pélissié, Benjamin; Jarne, Philippe; Sarda, Violette; David, Patrice

    2014-05-01

    Sexual selection operates on a sequence of events, from mating to offspring production. Which stages in this sequence undergo stronger selection, especially the relative importance of pre- versus postcopulatory processes, are intensely debated issues. Unequal siring success among mates of polyandrous females is classically taken as evidence for a large contribution of postcopulatory processes to the variance in male reproductive success (var(RSm )). However, paternity skews also depend on the timing and number of copulations, a source of variation that should be considered precopulatory rather than postcopulatory. We develop a method for decomposing var(RSm ) accounting for copulatory activity and apply it to experimental mating groups of the snail Physa acuta. In our experiment, 40% of var(RSm ) emerges at the precopulatory stage, only half of which depends on variation in mating success (number of partners). Ignoring copulation characteristics can therefore lead to severe underestimation of precopulatory sexual selection. Moreover, although only 36% of var(RSm ) arises at the postcopulatory stage, this is when sexual selection on body weight mostly occurs. Finally, trade-offs were detected between different components of precopulatory success, whereas pre- and postcopulatory success appear independent. Our study opens the way to a detailed quantitative understanding of sexual selection in polyandrous species. PMID:24410424

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

    PubMed

    Servedio, Maria R; Bürger, Reinhard

    2014-06-01

    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

  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. Sexual species are separated by larger genetic gaps than asexual species in rotifers.

    PubMed

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

    2014-10-01

    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

  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. Analysis of nrDNA polymorphism in closely related diploid sexual, tetraploid sexual and polyploid agamospermous species

    Microsoft Academic Search

    Lenka Záveská Drábková; Jan Kirschner; Jan Št?pánek; Lud?k Záveský; ?estmír Vl?ek

    2009-01-01

    Nuclear sequences of ITS1-5.8S-ITS2 region of rDNA may be an important source of phylogenetically informative data provided\\u000a that nrDNA is cloned and the character of sequence variation of clones is properly analyzed. nrDNA of selected Taraxacum sections was studied to show sequence variation differences among diploid sexual, tetraploid sexual and polyploid agamospermous\\u000a species. We examined nucleotide characteristics, substitution pattern, secondary

  14. PARASITES AND SEXUAL REPRODUCTION IN PSYCHID MOTHS

    Microsoft Academic Search

    Tomi Kumpulainen; Alessandro Grapputo; Johanna Mappes

    2004-01-01

    Persistence of sexual reproduction among coexisting asexual competitors has been a major paradox in evolutionary biology. The number of empirical studies is still very limited, as few systems with coexisting sexual and strictly asexual lineages have been found. We studied the ecological mechanisms behind the simultaneous coexistence of a sexually and an asexually reproducing closely related species of psychid moth

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

    E-print Network

    Little, Tony

    Symmetry 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 in terms of attractiveness. Faces have the potential to be advertisements of mate quality and both symmetry

  16. Sexual and asexual reproduction of the holothurian Stichopus chloronotus (Echinodermata): a comparison between La Réunion (Indian Ocean) and east Australia (Pacific Ocean)

    Microsoft Academic Search

    CHANTAL CONAND; SVEN UTHICKE; THIERRY HOAREAU

    2002-01-01

    Stichopus chloronotus (Brandt, 1835) is one among nine aspidochirotide holothurian species known to reproduce both sexually by broadcast spawning and asexually by transverse fission. New data on the sexual cycle of this species in La Réunion are presented here and information available on sexual and asexual reproduction in this species is summarised. Sexual reproduction on La Réunion shows a distinct

  17. 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

  18. Virulence and isozyme diversity of sexual versus asexual collections of Uromyces appendiculatus (bean rust fungus)

    Microsoft Academic Search

    James V Groth; John W McCain; Alan P Roelfs

    1995-01-01

    Organisms that reproduce sexually have been assumed to be more genetically diverse (have more phenotypes with a more even frequency distribution) than those that are clonal. Rust fungi usually have regular sexual reproduction, but asexual species or populations are not uncommon. Two field collections of the bean rust fungus from sexually reproducing populations were compared with two collections from apparently

  19. Multisite Reproducibility of the Broth Microdilution Method for Susceptibility Testing of Nocardia Species

    PubMed Central

    Brown-Elliott, Barbara A.; Wallace, Richard J.; Witebsky, Frank G.; Koziol, Deloris; Hall, Geraldine S.; Killian, Scott B.; Knapp, Cindy C.; Warshauer, David; Van, Tam; Wengenack, Nancy L.; Deml, Sharon; Woods, Gail L.

    2012-01-01

    Antimicrobial susceptibility testing (AST) of clinical isolates of Nocardia is recommended to detect resistance to commonly used antimicrobial agents; such testing is complicated by difficulties in inoculum preparation and test interpretation. In this study, six laboratories performed repetitive broth microdilution testing on single strains of Nocardia brasiliensis, Nocardia cyriacigeorgica, Nocardia farcinica, Nocardia nova, and Nocardia wallacei. For each isolate, a total of 30 microdilution panels from three different lots were tested at most sites. The goal of the study was to determine the inter- and intralaboratory reproducibility of susceptibility testing of this group of isolates. Acceptable agreement (>90% agreement at ±1 dilution of the MIC mode) was found for amikacin, ciprofloxacin, clarithromycin, and moxifloxacin. After eliminating MIC values from single laboratories whose results showed the greatest deviation from those of the remaining laboratories, acceptable agreement was also found for amoxicillin-clavulanic acid, linezolid, minocycline, and tobramycin. Results showed unsatisfactory reproducibility of broth microdilution testing of ceftriaxone with N. cyriacigeorgica and N. wallacei, tigecycline with N. brasiliensis and N. cyriacigeorgica, and sulfonamides with N. farcinica and N. wallacei. N. nova ATCC BAA-2227 is proposed as a quality control organism for AST of Nocardia sp., and the use of a disk diffusion test for sulfisoxazole is proposed as a check of the adequacy of the inoculum and to confirm sulfonamide MIC results. PMID:22219309

  20. How to be a chaste species pluralist-realist: the origins of species modes and the synapomorphic species concept

    Microsoft Academic Search

    John S. Wilkins

    2003-01-01

    The biological species (biospecies) concept applies only to sexually reproducing species, which means that until sexual reproduction evolved, there were no biospecies. On the universal tree of life, biospecies concepts therefore apply only to a relatively small number of clades, notably plants andanimals. I argue that it is useful to treat the various ways of being a species (species modes)

  1. Genomic and population analyses of the mating type loci in Coccidioides species reveal evidence for sexual reproduction and gene acquisition.

    PubMed

    Mandel, M Alejandra; Barker, Bridget M; Kroken, Scott; Rounsley, Steven D; Orbach, Marc J

    2007-07-01

    Coccidioides species, the fungi responsible for the valley fever disease, are known to reproduce asexually through the production of arthroconidia that are the infectious propagules. The possible role of sexual reproduction in the survival and dispersal of these pathogens is unexplored. To determine the potential for mating of Coccidioides, we analyzed genome sequences and identified mating type loci characteristic of heterothallic ascomycetes. Coccidioides strains contain either a MAT1-1 or a MAT1-2 idiomorph, which is 8.1 or 9 kb in length, respectively, the longest reported for any ascomycete species. These idiomorphs contain four or five genes, respectively, more than are present in the MAT loci of most ascomycetes. Along with their cDNA structures, we determined that all genes in the MAT loci are transcribed. Two genes frequently found in common sequences flanking MAT idiomorphs, APN2 and COX13, are within the MAT loci in Coccidioides, but the MAT1-1 and MAT1-2 copies have diverged dramatically from each other. Data indicate that the acquisition of these genes in the MAT loci occurred prior to the separation of Coccidioides from Uncinocarpus reesii. An analysis of 436 Coccidioides isolates from patients and the environment indicates that in both Coccidioides immitis and C. posadasii, there is a 1:1 distribution of MAT loci, as would be expected for sexually reproducing species. In addition, an analysis of isolates obtained from 11 soil samples demonstrated that at three sampling sites, strains of both mating types were present, indicating that compatible strains were in close proximity in the environment. PMID:17513566

  2. NEUTRAL MODELS FAIL TO REPRODUCE OBSERVED SPECIES–AREA AND SPECIES–TIME RELATIONSHIPS IN KANSAS GRASSLANDS

    Microsoft Academic Search

    Peter B. Adler

    2004-01-01

    In contrast to competing explanations of species-area relationships (SARs), neutral theory is dynamic, meaning that it should explain patterns in both space and time. However, most empirical tests of neutral theory have relied on snapshots, such as com- parisons of observed and simulated SARs observed at one point in time. I used 35 years of data from permanent plots in

  3. Is sexual selection and species recognition a continuum? Mating behavior of the stalk-eyed fly Drosophila heteroneura.

    PubMed

    Boake, C R; DeAngelis, M P; Andreadis, D K

    1997-11-11

    If behavioral isolation between species can evolve as a consequence of sexual selection within a species, then traits that are both sexually selected and used as a criterion of species recognition by females should be identifiable. The broad male head of the Hawaiian picture-winged fly Drosophila heteroneura is a novel sexual dimorphism that may be sexually selected and involved in behavioral isolation from D. silvestris. We found that males with broad heads are more successful in sexual selection, both through female mate choice and through aggressive interactions. However, female D. heteroneura do not discriminate against hybrids on the basis of their head width. Thus, this novel trait is sexually selected but is not a major contributor to species recognition. Our methods should be applicable to other species in which behavioral isolation is a factor. PMID:9356468

  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. Expression of sexual ornaments in a polymorphic species: phenotypic variation in response to environmental risk.

    PubMed

    Winandy, L; Denoël, M

    2015-05-01

    Secondary sexual traits may evolve under the antagonistic context of sexual and natural selection. In some polymorphic species, these traits are only expressed during the breeding period and are differently expressed in alternative phenotypes. However, it is unknown whether such phenotypes exhibit phenotypic plasticity of seasonal ornamentations in response to environmental pressures such as in the presence of fish (predation risk). This is an important question to understand the evolution of polyphenisms. We used facultative paedomorphosis in newts as a model system because it involves the coexistence of paedomorphs that retain gills in the adult stage with metamorphs that have undergone metamorphosis, but also because newts exhibit seasonal sexual traits. Our aim was therefore to determine the influence of fish on the development of seasonal ornamentation in the two phenotypes of the palmate newt (Lissotriton helveticus). During the entire newt breeding period, we assessed the importance of phenotype and fish presence with an information-theoretic approach. Our results showed that paedomorphs presented much less developed ornamentation than metamorphs and those ornamentations varied over time. Fish inhibited the development of sexual traits but differently between phenotypes: in contrast to metamorphs, paedomorphs lack the phenotypic plasticity of sexual traits to environmental risk. This study points out that internal and external parameters act in complex ways in the expression of seasonal sexual ornamentations and that similar environmental pressure can induce a contrasted evolution in alternative phenotypes. PMID:25847588

  6. Chance establishment for sexual, semelparous species: overcoming the Allee effect.

    PubMed

    Jerde, Christopher L; Bampfylde, Caroline J; Lewis, Mark A

    2009-06-01

    We formalize the establishment process for a sexual, semelparous organism through the use of hierarchical probability modeling from parameters of survival, probability of being female, probability of being fertilized, and expected fecundity. We show how to calculate the expected per capita growth rate and probability of extinction. An Allee effect is observed if the expected population growth rate decreases as the initial population size decreases. The model can be further extended as a stochastic process to evaluate the probability of extinction in subsequent generations. One of the novel results is the formulation of an analytical probability distribution for the next generation population size. As case studies, we use the Chinese mitten crab (Eriocheir sinensis) and the apple snail (Pomacea canaliculata), both of which appear on the World Conservation Union's list of 100 worst invaders. We evaluate the strength of the Allee effect and conclude that apple snails experience a weak Allee effect and Chinese mitten crabs experience a strong Allee effect. We emphasize one scenario where the stochastic process reveals that invasion risk can be estimated by the probability of the survival of one fertilized female, because the expected fecundity for one surviving female overwhelms the system such that population persistence is almost certain. PMID:19368522

  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. Distinguishing between Incomplete Lineage Sorting and Genomic Introgressions: Complete Fixation of Allospecific Mitochondrial DNA in a Sexually Reproducing Fish (Cobitis; Teleostei), despite Clonal Reproduction of Hybrids

    PubMed Central

    Choleva, Lukas; Musilova, Zuzana; Kohoutova-Sediva, Alena; Paces, Jan; Rab, Petr; Janko, Karel

    2014-01-01

    Distinguishing between hybrid introgression and incomplete lineage sorting causing incongruence among gene trees in that they exhibit topological differences requires application of statistical approaches that are based on biologically relevant models. Such study is especially challenging in hybrid systems, where usual vectors mediating interspecific gene transfers - hybrids with Mendelian heredity - are absent or unknown. Here we study a complex of hybridizing species, which are known to produce clonal hybrids, to discover how one of the species, Cobitis tanaitica, has achieved a pattern of mito-nuclear mosaic genome over the whole geographic range. We appplied three distinct methods, including the method using solely the information on gene tree topologies, and found that the contrasting mito-nuclear signal might not have resulted from the retention of ancestral polymorphism. Instead, we found two signs of hybridization events related to C. tanaitica; one concerning nuclear gene flow and the other suggested mitochondrial capture. Interestingly, clonal inheritance (gynogenesis) of contemporary hybrids prevents genomic introgressions and non-clonal hybrids are either absent or too rare to be detected among European Cobitis. Our analyses therefore suggest that introgressive hybridizations are rather old episodes, mediated by previously existing hybrids whose inheritance was not entirely clonal. Cobitis complex thus supports the view that the type of resulting hybrids depends on a level of genomic divergence between sexual species. PMID:24971792

  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. Genetics of sexual isolation based on courtship song between two sympatric species: Drosophila ananassae and D. pallidosa.

    PubMed

    Yamada, Hirokazu; Matsuda, Muneo; Oguma, Yuzuru

    2002-11-01

    Sexual isolation has been considered one of the primary causes of speciation and its genetic study has the potential to reveal the genetics of speciation. In Drosophila, the importance of courtship songs in sexual isolation between closely related species has been well investigated, but studies analysing the genetic basis of the difference in the courtship songs associated with sexual isolation are less well documented. Drosophila ananassae and Drosophila pallidosa are useful for studies of sexual isolation, because of their sympatric distribution and absence of postmating isolation. Courtship songs are known to play a crucial role in sexual isolation between these two species, and the female discrimination behaviour against the courting male has been revealed to be controlled by a very narrow region on the second chromosome. In this study we investigated the genetic basis controlling the song differences associated with their sexual isolation, using intact and wingless males with chromosomes substituted between species. The results obtained from F1 hybrid males between these species indicate the dominance of the song characters favoured by D. pallidosa females. In addition, the results obtained from backcross F2 males indicate that chromosome 2 had a major effect on the control of the song characters associated with sexual isolation. PMID:12555781

  11. How do viviparous and oviparous lizards reproduce in Patagonia? A comparative study of three species of Liolaemus

    Microsoft Academic Search

    M. Medina; N. R. Ibargüengoytía

    2010-01-01

    In the cold temperate climate of Patagonia, reproduction and growth of ectotherms are restricted to brief seasons, particularly at high latitudes. This energy constraint has affected the evolution of life history traits such as sexual maturity, clutch size, offspring size, reproductive effort, and fecundity. Limitations on the timing of reproductive events and the allocation of energy to offspring have a

  12. 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

  13. Prenatal sex ratios and expression of sexually dimorphic traits in three snake species.

    PubMed

    Weatherhead, Patrick James; Kissner, Kelley Joan; Sommerer, Sophie Jane

    2006-08-01

    Variation in intrauterine exposure to hormones associated with variation in the sex of litter mates has well-established and far-reaching effects on sexual development in some mammals. Research on this phenomenon in reptiles is scant, but suggests that lizards may follow the mammalian model whereas snakes may be affected differently. We examined sex-specific expression of four sexually dimorphic traits (tail length, head length, ventral scale count, swimming speed) in three species of snakes (Nerodia sipedon, Thamnophis sirtalis, T. sauritus) relative to litter sex ratios. We found little evidence that traits in either sex were masculinized or feminized in response to variation in litter sex ratio. The one significant result appeared best explained as a statistical artifact attributable to a single litter. Our results indicate that snakes are different from the one lizard studied to date. Unlike previous suggestions that prenatal hormonal mechanisms operate differently in snakes and lizards, however, the difference appears to be that development of sexually dimorphic traits in lizards is affected by litter sex ratios whereas in snakes it is not. PMID:16788914

  14. Altering sexual reproductive mode by interspecific exchange of MAT loci

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sexual fungi can be self-sterile (heterothallic, requiring genetically distinct partners) or selffertile (homothallic, no partner required). In most ascomycetes, a single mating type locus (MAT) controls the ability to reproduce sexually. In the genus Cochliobolus, all heterothallic species have eit...

  15. 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

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

    PubMed

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

    2004-06-22

    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

  17. 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.

  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. 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

  20. [Morphogenesis of the sexual phase of six Mexican species of the Dryopteris (Dryopteridaceae), Part II].

    PubMed

    Pérez-García, B; Mendoza, A; Reyes Jaramillo, I; Riba, R

    2001-03-01

    The development of the sexual phase of six Mexican species of Dryopteris is described and compared. Spores of all studied species are monolete, ellipsoid and have a rugose surface; the perine is folded, brown to dark brown, with a tubercled outline. Germination pattern is of the Vittaria-type and the development pattern of the prothallia is of the Aspidium-type. Gametangia are of the common type for the leptosporangiate advanced ferns. First leaves of the sporophytes appear 258-265 after sowing and apparently in Dryopteris pseudo-filix-mas the sporophyte have an apogamic origin (80 days). To make a comparative analysis of gametophytic characteristics in the twelve Mexican species and conclude of germination is of the Vittaria-type and development pattern prothallial is of the Aspidium-type, and unicelular trichomes on margin and superficial gametophytic to yield irregular aspect are characteristics to yield unit and characteristic to genera to conform Dryopteridaceae family (sensu Moran 1995) with the exception of Didymochlaena genus. PMID:11795155

  1. Applying the species concept to plant viruses

    Microsoft Academic Search

    M. H. V. Van Regenmortel

    1989-01-01

    Summary Plant virologists who maintain that the concept of species cannot be applied to viruses argue their case in terms of an obsolete concept of biological species defined by gene pools and reproductive isolation and applicable only to sexually reproducing organisms. In fact, various species concepts have been used by biologists and some of them are applicable to asexual organisms.

  2. 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

  3. Evidence for a sexual dimorphism in gene expression noise in metazoan species.

    PubMed

    Díaz-Castillo, Carlos

    2015-01-01

    Many biological processes depend on very few copies of intervening elements, which makes such processes particularly susceptible to the stochastic fluctuations of these elements. The intrinsic stochasticity of certain processes is propagated across biological levels, causing genotype- and environment-independent biological variation which might permit populations to better cope with variable environments. Biological variations of stochastic nature might also allow the accumulation of variations at the genetic level that are hidden from natural selection, which might have a great potential for population diversification. The study of any mechanism that resulted in the modulation of stochastic variation is, therefore, of potentially wide interest. I propose that sex might be an important modulator of the stochastic variation in gene expression, i.e., gene expression noise. Based on known associations between different patterns of gene expression variation, I hypothesize that in metazoans the gene expression noise might be generally larger in heterogametic than in homogametic individuals. I directly tested this hypothesis by comparing putative genotype- and environment-independent variations in gene expression between females and males of Drosophila melanogaster strains. Also, considering the potential effect of the propagation of gene expression noise across biological levels, I indirectly tested the existence of a metazoan sexual dimorphism in gene expression noise by analyzing putative genotype- and environment-independent variation in phenotypes related to interaction with the environment in D. melanogaster strains and metazoan species. The results of these analyses are consistent with the hypothesis that gene expression is generally noisier in heterogametic than in homogametic individuals. Further analyses and discussion of existing literature permits the speculation that the sexual dimorphism in gene expression noise is ultimately based on the nuclear dynamics in gametogenesis and very early embryogenesis of sex-specific chromosomes, i.e., Y and W chromosomes. PMID:25649874

  4. Floral odour chemistry defines species boundaries and underpins strong reproductive isolation in sexually deceptive orchids

    PubMed Central

    Peakall, Rod; Whitehead, Michael R.

    2014-01-01

    Background and Aims The events leading to speciation are best investigated in systems where speciation is ongoing or incomplete, such as incipient species. By examining reproductive barriers among incipient sister taxa and their congeners we can gain valuable insights into the relative timing and importance of the various barriers involved in the speciation process. The aim of this study was to identify the reproductive barriers among sexually deceptive orchid taxa in the genus Chiloglottis. Methods The study targeted four closely related taxa with varying degrees of geographic overlap. Chemical, morphological and genetic evidence was combined to explore the basis of reproductive isolation. Of primary interest was the degree of genetic differentiation among taxa at both nuclear and chloroplast DNA markers. To objectively test whether or not species boundaries are defined by the chemistry that controls pollinator specificity, genetic analysis was restricted to samples of known odour chemistry. Key Results Floral odour chemical analysis was performed for 600+ flowers. The three sympatric taxa were defined by their specific chiloglottones, the semiochemicals responsible for pollinator attraction, and were found to be fully cross-compatible. Multivariate morphometric analysis could not reliably distinguish among the four taxa. Although varying from very low to moderate, significant levels of genetic differentiation were detected among all pairwise combinations of taxa at both nuclear and chloroplast loci. However, the levels of genetic differentiation were lower than expected for mature species. Critically, a lack of chloroplast DNA haplotype sharing among the morphologically indistinguishable and most closely related taxon pair confirmed that chemistry alone can define taxon boundaries. Conclusions The results confirmed that pollinator isolation, mediated by specific pollinator attraction, underpins strong reproductive isolation in these taxa. A combination of large effective population sizes, initial neutral mutations in the genes controlling floral scent, and a pool of available pollinators likely drives diversity in this system. PMID:24052555

  5. 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)

  6. Visual discrimination between two sexually deceptive Ophrys species by a bee pollinator.

    PubMed

    Streinzer, M; Ellis, T; Paulus, H F; Spaethe, J

    2010-09-01

    Almost all species of the orchid genus Ophrys are pollinated by sexual deception. The orchids mimic the sex pheromone of receptive female insects, mainly hymenopterans, in order to attract males seeking to copulate. Most Ophrys species have achromatic flowers, but some exhibit a coloured perianth and a bright, conspicuous labellum pattern. We recently showed that the pink perianth of Ophrys heldreichii flowers increases detectability by its pollinator, males of the long-horned bee Eucera berlandi. Here we tested the hypothesis that the bright, complex labellum pattern mimics the female of the pollinator to increase attractiveness toward males. In a dual-choice test we offered E. berlandi males an O. heldreichii flower and a flower from O. dictynnae, which also exhibits a pinkish perianth but no conspicuous labellum pattern. Both flowers were housed in UV-transmitting acrylic glass boxes to exclude olfactory signals. Males significantly preferred O. heldreichii to O. dictynnae flowers. In a second experiment, we replaced the perianth of both flowers with identical artificial perianths made from pink card, so that only the labellum differed between the two flower stimuli. Males then chose between both stimuli at random, suggesting that the presence of a labellum pattern does not affect their choice. Spectral measurements revealed higher colour contrast with the background of the perianth of O. heldreichii compared to O. dictynnae, but no difference in green receptor-specific contrast or brightness. Our results show that male choice is guided by the chromatic contrast of the perianth during the initial flower approach but is not affected by the presence of a labellum pattern. Instead, we hypothesise that the labellum pattern is involved in aversive learning during post-copulatory behaviour and used by the orchid as a strategy to increase outcrossing. PMID:21516265

  7. Physical and Linkage Maps for Drosophila serrata, a Model Species for Studies of Clinal Adaptation and Sexual Selection

    PubMed Central

    Stocker, Ann J.; Rusuwa, Bosco B.; Blacket, Mark J.; Frentiu, Francesca D.; Sullivan, Mitchell; Foley, Bradley R.; Beatson, Scott; Hoffmann, Ary A.; Chenoweth, Stephen F.

    2012-01-01

    Drosophila serrata is a member of the montium group, which contains more than 98 species and until recently was considered a subgroup within the melanogaster group. This Drosophila species is an emerging model system for evolutionary quantitative genetics and has been used in studies of species borders, clinal variation and sexual selection. Despite the importance of D. serrata as a model for evolutionary research, our poor understanding of its genome remains a significant limitation. Here, we provide a first-generation gene-based linkage map and a physical map for this species. Consistent with previous studies of other drosophilids we observed strong conservation of genes within chromosome arms homologous with D. melanogaster but major differences in within-arm synteny. These resources will be a useful complement to ongoing genome sequencing efforts and QTL mapping studies in this species. PMID:22384407

  8. 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

  9. Molecular and morphological data support the existence of a sexual cycle in species of the genus Paracoccidioides.

    PubMed

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

    2013-03-01

    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. 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

  11. Species-specific patterns of sexual dimorphism in the expression of fruitless protein, a neural musculinizing factor in Drosophila.

    PubMed

    Usui-Aoki, Kazue; Mikawa, Yoshitaka; Yamamoto, Daisuke

    2005-01-01

    In Drosophila melanogaster, male-specific forms of the fruitless (fru) gene product, mFru protein, function as a neural sex-determination factors that directs the development of at least two male characteristics, namely courtship and mating behavior and the formation of the muscle of Lawrence (MOL). In D. melanogaster, the male-specific expression of Fru protein in motoneurons is responsible for the male-limited induction of the MOL by such neurons. Although no Drosophila species whose females have the MOL are known, there are many Drosophila species whose males lack the MOL. We performed immunohistochemical staining of the central nervous system (CNS) from 9 Drosophila species to determine whether the mFru expression profile is different between MOL-present and MOL-absent species. In 8 of the 9 species, Fru protein expression in the CNS is strictly male-specific, regardless of the presence or absence of the MOL. The sole exception is D. suzukii, in which females express the Fru protein though less extensively than males do: Fru expression in the CNS of female D. suzukii is restricted to the lamina and ventral ganglia. Expression of Fru protein in the lamina is observed in males of D. virilis and in both sexes of D. suzukii, but not in males and females of the 7 other species. These results indicate that sexually dimorphic expression of the Fru protein has been subjected to species-specific modulation during evolution. PMID:16024442

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

    PubMed Central

    Little, Anthony C.; Jones, Benedict C.; Waitt, Corri; Tiddeman, Bernard P.; Feinberg, David R.; Perrett, David I.; Apicella, Coren L.; Marlowe, Frank W.

    2008-01-01

    Background Many animals both display and assess multiple signals. Two prominently studied traits are symmetry and sexual dimorphism, which, for many animals, are proposed cues to heritable fitness benefits. These traits are associated with other potential benefits, such as fertility. In humans, the face has been extensively studied in terms of attractiveness. Faces have the potential to be advertisements of mate quality and both symmetry and sexual dimorphism have been linked to the attractiveness of human face shape. Methodology/Principal Findings Here we show that measurements of symmetry and sexual dimorphism from faces are related in humans, both in Europeans and African hunter-gatherers, and in a non-human primate. Using human judges, symmetry measurements were also related to perceived sexual dimorphism. In all samples, symmetric males had more masculine facial proportions and symmetric females had more feminine facial proportions. Conclusions/Significance Our findings support the claim that sexual dimorphism and symmetry in faces are signals advertising quality by providing evidence that there must be a biological mechanism linking the two traits during development. Such data also suggests that the signalling properties of faces are universal across human populations and are potentially phylogenetically old in primates. PMID:18461131

  13. Species abundance, sexual encounter and bioluminescent signalling in the deep sea.

    PubMed Central

    Herring, P J

    2000-01-01

    The problems faced by deep-sea animals in achieving sexual and other encounters require sensory and effector systems the synergy of which can span the often very substantial distances that separate individuals. Bioluminescent systems provide one of the links between individuals, and the sexual dimorphism of some photophores suggests that they are employed to attract a mate. However, nearest-neighbour values for many deep-sea animals put them beyond the effective range of bioluminescent signals and it is therefore likely that these signals are employed at intermediate ranges, once an initial contact (perhaps olfactory) has been made. PMID:11079413

  14. Mating Systems, Reproductive Success, and Sexual Selection in Secretive Species: A Case Study of the

    E-print Network

    Clark, Rulon W.

    of the Western Diamond-Backed Rattlesnake, Crotalus atrox Rulon W. Clark1 *, Gordon W. Schuett2,3,4 *, Roger A diamond-backed rattlesnake (Crotalus atrox) for an analysis of its mating system and to measure sexual of the Western Diamond-Backed Rattlesnake, Crotalus atrox. PLoS ONE 9(3): e90616. doi:10.1371/journal

  15. Population genetic structure of diploid sexual and polyploid apomictic hawthorns ( Crataegus ; Rosaceae) in the Pacific Northwest

    Microsoft Academic Search

    EUGENIA Y. Y. LO; SAŠA STEFANOVI?; TIMOTHY A. DICKINSON

    2009-01-01

    Polyploidy and gametophytic apomixis are two important and associated processes in plants. Many hawthorn species are polyploids and can reproduce both sexually and apomictically. However, the population genetic structure of these species is poorly understood. Crataegus douglasii is represented exclusively by self-compatible tetraploid pseudogamous apomicts across North America, whereas Crataegus suksdorfii found in the Pacific Northwest is known to include

  16. 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

  17. 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

  18. Larval feeding substrate and species significantly influence the effect of juvenile hormone analog on sexual development/performance in four tropical tephritid flies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The juvenile hormone analog methoprene reduces the amount of time it takes laboratory-reared Anastrepha suspensa (Caribbean fruit fly) males to reach sexual maturity by almost half. Here, we examined if methoprene exerted a similar effect on four other species of Anastrepha (A. ludens, A. obliqua, ...

  19. 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

  20. Sexual comparisons in immune ability, survival and parasite intensity in two damselfly species

    Microsoft Academic Search

    A. Córdoba-Aguilar; J. Contreras-Garduño; A. Luna-González; A. I. Campa-Córdova; F. Ascencio

    2006-01-01

    Recent evolutionary studies have suggested that females have a more robust immune system than males. Using two damselfly species (Hetaerina americana and Argia tezpi), we tested if females produced higher immune responses (as phenoloxidase and hydrolytic enzymes), had a higher survival (using a nylon implant inserted in the abdomen and measuring survival after 24h) and fewer parasites (gregarines and water

  1. 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

  2. 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

  3. Notes: Sexual Dimorphism of Pelvic Fin Shape in Four Species of Catostomidae

    Microsoft Academic Search

    David R. Stanley

    1988-01-01

    Pelvic fin dimorphism was used as an external indicator of sex of northern hog suckers Hypentelium nigricans, shorthead redhorses Moxostoma macrolepidotum, longnose suckers Catostomus catostomus, and white suckers Catostomus commersoni. Sex of the four species ofcatostomids examined can be determined externally by two calculations: (1) linear regression of the seventh pelvic fin ray length on fork length, (2) ratio of

  4. Exposure to an environmental estrogen breaks down sexual isolation between native and invasive species

    PubMed Central

    Ward, Jessica L; Blum, Michael J

    2012-01-01

    Environmental change can increase the likelihood of interspecific hybridization by altering properties of mate recognition and discrimination between sympatric congeners. We examined how exposure to an environmentally widespread endocrine-disrupting chemical (EDC), bisphenol A (BPA), affected visual communication signals and behavioral isolation between an introduced freshwater fish and a native congener (genus: Cyprinella). Exposure to BPA induced changes in the expression of male secondary traits as well as male and female mate choice, leading to an overall reduction in prezygotic isolation between congeners. Changes in female mate discrimination were not tightly linked to changes in male phenotypic traits, suggesting that EDC exposure may alter female choice thresholds independently of the effects of exposure on males. These findings indicate that environmental exposure to EDCs can lead to population declines via the erosion of species boundaries and by promoting the establishment and spread of non-native species via hybridization. PMID:23346234

  5. Sexual comparisons in immune ability, survival and parasite intensity in two damselfly species.

    PubMed

    Córdoba-Aguilar, A; Contreras-Garduño, J; Peralta-Vázquez, H; Luna-González, A; Campa-Córdova, A I; Ascencio, F

    2006-08-01

    Recent evolutionary studies have suggested that females have a more robust immune system than males. Using two damselfly species (Hetaerina americana and Argia tezpi), we tested if females produced higher immune responses (as phenoloxidase and hydrolytic enzymes), had a higher survival (using a nylon implant inserted in the abdomen and measuring survival after 24h) and fewer parasites (gregarines and water mites) than males. We also tested whether immune differences should emerge in different body areas (thorax vs. abdomen) within each sex with the prediction that only females will differ with the abdomen having a higher immune response than their thorax since the former area, for ecological and physiological reasons, may be a target zone for increased immune investment. Animals were adults of approximately the same age. In both species, females were more immunocompetent than males, but only in H. americana females were immune responses greater in the abdomen than in the thorax. However, there were no differences in survival and parasite intensity or the probability of being parasitised between the sexes in either of the two species. Thus, this study lends partial support to the principle that females are better at defending than males despite the null difference in parasitism and survival. PMID:16843483

  6. Sexual Assault

    MedlinePLUS

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

  7. Extensive variation in chromosome number and genome size in sexual and parthenogenetic species of the jumping-bristletail genus Machilis (Archaeognatha).

    PubMed

    Gassner, Melitta; Dejaco, Thomas; Schönswetter, Peter; Marec, František; Arthofer, Wolfgang; Schlick-Steiner, Birgit C; Steiner, Florian M

    2014-11-01

    Parthenogenesis in animals is often associated with polyploidy and restriction to extreme habitats or recently deglaciated areas. It has been hypothesized that benefits conferred by asexual reproduction and polyploidy are essential for colonizing these habitats. However, while evolutionary routes to parthenogenesis are manifold, study systems including polyploids are scarce in arthropods. The jumping-bristletail genus Machilis (Insecta: Archaeognatha) includes both sexual and parthenogenetic species, and recently, the occurrence of polyploidy has been postulated. Here, we applied flow cytometry, karyotyping, and mitochondrial DNA sequencing to three sexual and five putatively parthenogenetic Eastern-Alpine Machilis species to investigate whether (1) parthenogenesis originated once or multiply and (2) whether parthenogenesis is strictly associated with polyploidy. The mitochondrial phylogeny revealed that parthenogenesis evolved at least five times independently among Eastern-Alpine representatives of this genus. One parthenogenetic species was exclusively triploid, while a second consisted of both diploid and triploid populations. The three other parthenogenetic species and all sexual species were diploid. Our results thus indicate that polyploidy can co-occur with parthenogenesis, but that it was not mandatory for the emergence of parthenogenesis in Machilis. Overall, we found a weak negative correlation of monoploid genome size (Cx) and chromosome base number (x), and this connection is stronger among parthenogenetic species alone. Likewise, monoploid genome size decreased with elevation, and we therefore hypothesize that genome downsizing could have been crucial for the persistence of alpine Machilis species. Finally, we discuss the evolutionary consequences of intraspecific chromosomal rearrangements and the presence of B chromosomes. In doing so, we highlight the potential of Alpine Machilis species for research on chromosomal and genome-size alterations during speciation. PMID:25505536

  8. Extensive variation in chromosome number and genome size in sexual and parthenogenetic species of the jumping-bristletail genus Machilis (Archaeognatha)

    PubMed Central

    Gassner, Melitta; Dejaco, Thomas; Schönswetter, Peter; Marec, František; Arthofer, Wolfgang; Schlick-Steiner, Birgit C; Steiner, Florian M

    2014-01-01

    Parthenogenesis in animals is often associated with polyploidy and restriction to extreme habitats or recently deglaciated areas. It has been hypothesized that benefits conferred by asexual reproduction and polyploidy are essential for colonizing these habitats. However, while evolutionary routes to parthenogenesis are manifold, study systems including polyploids are scarce in arthropods. The jumping-bristletail genus Machilis (Insecta: Archaeognatha) includes both sexual and parthenogenetic species, and recently, the occurrence of polyploidy has been postulated. Here, we applied flow cytometry, karyotyping, and mitochondrial DNA sequencing to three sexual and five putatively parthenogenetic Eastern-Alpine Machilis species to investigate whether (1) parthenogenesis originated once or multiply and (2) whether parthenogenesis is strictly associated with polyploidy. The mitochondrial phylogeny revealed that parthenogenesis evolved at least five times independently among Eastern-Alpine representatives of this genus. One parthenogenetic species was exclusively triploid, while a second consisted of both diploid and triploid populations. The three other parthenogenetic species and all sexual species were diploid. Our results thus indicate that polyploidy can co-occur with parthenogenesis, but that it was not mandatory for the emergence of parthenogenesis in Machilis. Overall, we found a weak negative correlation of monoploid genome size (Cx) and chromosome base number (x), and this connection is stronger among parthenogenetic species alone. Likewise, monoploid genome size decreased with elevation, and we therefore hypothesize that genome downsizing could have been crucial for the persistence of alpine Machilis species. Finally, we discuss the evolutionary consequences of intraspecific chromosomal rearrangements and the presence of B chromosomes. In doing so, we highlight the potential of Alpine Machilis species for research on chromosomal and genome-size alterations during speciation. PMID:25505536

  9. sexual Assault sexual Assault

    E-print Network

    Hickman, Mark

    sexual Assault sexual Assault if You Are a Victim of a sexual Assault 1. Get to a safe place. 2. Call out for help. 3. DiAl 6111 or ask someone to ring for you and state "sEXUAl AssAUlT" giving exact. if You Witness a sexual Assault 1. Everyone is asked to assist in making the campus a safe place by being

  10. 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 ...

  11. Sexual Assault

    MedlinePLUS

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

  12. Migration and the Origin of Species Claus Rueffler

    E-print Network

    Hermisson, Joachim

    to the biological relevant effect of migration in sexually reproducing plant and animal populations. Although still to be common. In Sect. 4, I present a classification of speciation scenarios based on the magnitude of gene into orders, orders into classes and classes into kingdoms. However, delineating species from each other has

  13. Sexual Health

    MedlinePLUS

    ... The Most Common Types of Sexual Problems in Older Adults For women, age-related changes due to menopause ... sexual intercourse. How Common are Sexual Problems in Older Adults? Researchers have found that about half of sexually ...

  14. Sexual Harassment and Sexual Bulllying

    MedlinePLUS

    ... Harassment and Sexual Bullying Print A A A Text Size What's in this article? What Are Sexual ... technology to harass someone sexually (like sending inappropriate text messages, pictures, or videos). Sometimes sexual harassment can ...

  15. 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

  16. Spontaneous hybrids between native and exotic Rubus in the Western United States produce offspring both by apomixis and by sexual recombination.

    PubMed

    Clark, L V; Jasieniuk, M

    2012-11-01

    Facultative asexual reproduction is a trait commonly found in invasive species. With a combination of sexual and asexual reproductive modes, such species may adapt to new environments via sexual recombination during range expansion, while at the same time having the benefits of asexuality such as the maintenance of fitness effects that depend upon heterozygosity. In the Western United States, native species of Rubus (Rosaceae) reproduce sexually whereas exotic naturalized Rubus species reproduce by pseudogamous apomixis. We hypothesized that new asexual lineages of Rubus could arise from hybridization in this range. To detect hybridization between native and exotic Rubus, we genotyped 579 individuals collected across California, Oregon and Washington with eight nuclear microsatellites and two chloroplast markers. Principal Coordinate Analysis and Bayesian clustering revealed a limited amount of hybridization of the native R. ursinus with the exotic R. armeniacus and R. pensilvanicus, as well as cultivated varieties. Genetic distances between these hybrids and their offspring indicated that both R. ursinus × R. armeniacus and R. ursinus × R. pensilvanicus produced a mix of apomictic and sexual seeds, with sexual seeds being more viable. Although neither of these hybrid types is currently considered invasive, they model the early stages of evolution of new invasive lineages, given the potential for fixed heterosis and the generation of novel genotypes. The hybrids also retain the ability to increase their fitness via sexual recombination and natural selection. Mixed reproductive systems such as those described here may be an important step in the evolution of asexual invasive species. PMID:22850699

  17. Spontaneous hybrids between native and exotic Rubus in the Western United States produce offspring both by apomixis and by sexual recombination

    PubMed Central

    Clark, L V; Jasieniuk, M

    2012-01-01

    Facultative asexual reproduction is a trait commonly found in invasive species. With a combination of sexual and asexual reproductive modes, such species may adapt to new environments via sexual recombination during range expansion, while at the same time having the benefits of asexuality such as the maintenance of fitness effects that depend upon heterozygosity. In the Western United States, native species of Rubus (Rosaceae) reproduce sexually whereas exotic naturalized Rubus species reproduce by pseudogamous apomixis. We hypothesized that new asexual lineages of Rubus could arise from hybridization in this range. To detect hybridization between native and exotic Rubus, we genotyped 579 individuals collected across California, Oregon and Washington with eight nuclear microsatellites and two chloroplast markers. Principal Coordinate Analysis and Bayesian clustering revealed a limited amount of hybridization of the native R. ursinus with the exotic R. armeniacus and R. pensilvanicus, as well as cultivated varieties. Genetic distances between these hybrids and their offspring indicated that both R. ursinus × R. armeniacus and R. ursinus × R. pensilvanicus produced a mix of apomictic and sexual seeds, with sexual seeds being more viable. Although neither of these hybrid types is currently considered invasive, they model the early stages of evolution of new invasive lineages, given the potential for fixed heterosis and the generation of novel genotypes. The hybrids also retain the ability to increase their fitness via sexual recombination and natural selection. Mixed reproductive systems such as those described here may be an important step in the evolution of asexual invasive species. PMID:22850699

  18. Sexually coercive male chimpanzees sire more offspring.

    PubMed

    Feldblum, Joseph T; Wroblewski, Emily E; Rudicell, Rebecca S; Hahn, Beatrice H; Paiva, Thais; Cetinkaya-Rundel, Mine; Pusey, Anne E; Gilby, Ian C

    2014-12-01

    In sexually reproducing animals, male and female reproductive strategies often conflict. In some species, males use aggression to overcome female choice, but debate persists over the extent to which this strategy is successful. Previous studies of male aggression toward females among wild chimpanzees have yielded contradictory results about the relationship between aggression and mating behavior. Critically, however, copulation frequency in primates is not always predictive of reproductive success. We analyzed a 17-year sample of behavioral and genetic data from the Kasekela chimpanzee (Pan troglodytes schweinfurthii) community in Gombe National Park, Tanzania, to test the hypothesis that male aggression toward females increases male reproductive success. We examined the effect of male aggression toward females during ovarian cycling, including periods when the females were sexually receptive (swollen) and periods when they were not. We found that, after controlling for confounding factors, male aggression during a female's swollen periods was positively correlated with copulation frequency. However, aggression toward swollen females was not predictive of paternity. Instead, aggression by high-ranking males toward females during their nonswollen periods was positively associated with likelihood of paternity. This indicates that long-term patterns of intimidation allow high-ranking males to increase their reproductive success, supporting the sexual coercion hypothesis. To our knowledge, this is the first study to present genetic evidence of sexual coercion as an adaptive strategy in a social mammal. PMID:25454788

  19. Endocrine control of sexual behavior in sneaker males of the peacock blenny Salaria pavo: Effects of castration, aromatase inhibition, testosterone and estradiol

    Microsoft Academic Search

    David Gonçalves; João Alpedrinha; Magda Teles; Rui F. Oliveira

    2007-01-01

    The effects of castration and sex steroid manipulations on the expression of sexual behavior were investigated in a small fish, the peacock blenny, Salaria pavo. In this species, large males defend nests and attract females while small “sneaker” males reproduce by imitating the female morphology and courtship behavior in order to approach nests during spawning events and parasitically fertilize eggs.

  20. 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...

  1. 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

  2. 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.

  3. 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 ...

  4. Examining Reproductive Strategies in an Asexually Reproducing Rotifer (Class Bdelloidea)

    Microsoft Academic Search

    Galbreath Kurt

    1997-01-01

    Nearly all multicelled organisms exhibit sexual reproduction. Rotifers of the class Bdelloidea, however, seem to be a notable exception to this pattern. No male bdelloid individuals have ever been observed and females apparently reproduce entirely through parthenogenesis. In this study, Philodina sp. was examined with the intent of addressing the following: 1) are bdelloids truly completely asexual? 2) if so,

  5. Lesbian Sexuality

    Microsoft Academic Search

    Pat Califia

    1979-01-01

    A study was conducted to determine what physical sexual activities lesbians engage in and what attitudes lesbians have toward various aspects of their sexuality. The sample consisted of 286 homosexual women. This article reports results in the following areas: first orgasm, first sexual experience with another women, sexual fantasies, number of sex partners, faking orgasm, sex toys, initiating sex, techniques

  6. 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

  7. Internet Sexualities

    Microsoft Academic Search

    Nicola Döring

    2010-01-01

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

  8. Mating system, sexual dimorphism, and the opportunity for sexual selection in a territorial ungulate

    Microsoft Academic Search

    Cecile Vanpe; Petter Kjellander; M. Galan; J.-F. Cosson; S. Aulagnier; O. Liberg; A. J. M. Hewison

    2007-01-01

    In mammals, species with high sexual size dimorphism tend to have highly polygynous mating systems associated with high variance in male lifetime reproductive success (LRS), leading to a high opportunity for sexual selection. However, little in- formation is available for species with weak sexual size dimorphism. In a long-term study population, we used parentage analysis based on 21 microsatellite markers

  9. The Effect of Temperature on Reproductive Characteristics of an Asexually Reproducing Rotifer (Class Bdelloidea)

    Microsoft Academic Search

    Kurt E. Galbreath

    1997-01-01

    Most organisms exhibit sexual reproduction. Rotifers of the class Bdelloidea, however, seem to be a notable exception to this pattern. No male bdelloid individuals have ever been observed, and females apparently reproduce entirely through parthenogenesis. Sexual reproduction occurs in rotifers of the class Monogononta, and in many cases it is induced by environmental cues (e.g. temperature, diet). In this study,

  10. 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. J. Cell. Physiol. 230: 2304-2310, 2015. © 2015 Wiley Periodicals, Inc. PMID:25740260

  11. Population dynamics with a mixed type of sexual and asexual reproduction in a fluctuating environment

    PubMed Central

    2012-01-01

    Background Carassius gibelio, a cyprinid fish from Eurasia, has the ability to reproduce both sexually and asexually. This fish is also known as an invasive species which colonized almost all continental Europe, most likely originating from Asia and Eastern Europe. Populations of both sexually and asexually reproducing individuals exist in sympatry. In this study we try to elucidate the advantages of such a mixed type of reproduction. We investigate the dynamics of two sympatric populations with sexual and asexual reproduction in a periodically fluctuating environment. We define an individual-based computational model in which genotypes are represented by L loci, and the environment is composed of L resources for which the two populations compete. Results Our model demonstrates advantageous population dynamics where the optimal percentage of asexual reproduction depends on selection strength, on the number of selected loci and on the timescale of environmental fluctuations. We show that the sexual reproduction is necessary for "generating" fit genotypes, while the asexual reproduction is suitable for "amplifying" them. The simulations show that the optimal percentage of asexual reproduction increases with the length of the environment stability period and decrease with the strength of the selection and the number of loci. Conclusions In this paper we addressed the advantages of a mixed type of sexual and asexual reproduction in a changing environment and explored the idea that a species that is able to adapt itself to environmental fluctuation can easily colonize a new habitat. Our results could provide a possible explanation for the rapid and efficient invasion of species with a variable ratio of sexual and asexual reproduction such as Carassius gibelio. PMID:22489797

  12. 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.”

  13. Setting the Default to Reproducible Reproducibility in Computational and

    E-print Network

    Borwein, Jonathan

    from the workshop discussions are: 1. It is important to promote a culture change that will integrate support this culture change. 3. Reproducible research practices and the use of appropriate tools should data and code. The "reproducible research" movement recognizes that traditional scientific research

  14. Sexual Health

    MedlinePLUS

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

  15. Adolescent Sexuality.

    ERIC Educational Resources Information Center

    Sharpe, Thomasina H.

    2003-01-01

    This article offers a medical and psychosocial perspective of adolescent sexual development. Sub-types of sexual development are discussed as well as treatment implications for allied health providers. (Contains 38 references.) (Author)

  16. Sexual Intimacy After Sexual Assault or Sexual Abuse1

    E-print Network

    Machel, Hans

    Sexual Intimacy After Sexual Assault or Sexual Abuse1 Many survivors find that their sexual attitudes and reactions are impacted after a sexual assault or sexual abuse. While these effects are not permanent, they can be very frustrating as they can decrease the enjoyment of one's sexual life and intimacy

  17. Sexual conflict

    Microsoft Academic Search

    Tracey Chapman; Göran Arnqvist; Jenny Bangham; Locke Rowe

    2003-01-01

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

  18. Genetic structure of populations of two closely related brittle stars with contrasting sexual and asexual life histories, with observations on the genetic structure of a second asexual species

    Microsoft Academic Search

    P. V. Mladenov; R. H. Emson

    1990-01-01

    Ophiocoma pumila Lütken andOphiocomella ophiactoides (H. L. Clark) are morphologically similar brittle stars with contrasting life histories, the former obligately sexual, the latter fissiparous (capable of both sexual reproduction and asexual proliferation by binary fission). Electrophoretic analysis of five polymorphic enzymes was used to assess the genetic consequences of these differing life histories and provide a genetic perspective on the

  19. The roots of sexual arousal and sexual orientation.

    PubMed

    Salu, Yehuda

    2011-03-01

    Unlike members of other species that are genetically wired to be attracted to their sexual partners, humans learn the cues that guide them in choosing their sexual partners and that trigger sexual arousal. Genetically wired mechanisms must be directing the acquisition of those cues and organizing them in information structures that underlie human sexual behavior. Individual sexuality is a combination of the genetic mechanisms and information learned through personal experiences. This article focuses on the roots of human sexuality - on genetically embedded mechanisms, common to all humans, around which the wide variety of sexual behaviors is built. It proposes a model that defines the basic mechanisms and their role in developing individual sexuality. It is suggested that three brain areas host the roots of human sexuality: the auditory area, which provides stimuli that serve as cues for the identification of a mate; an emotional area, which provides cues for emotional arousal; and a corporal area, which controls the physiological expressions of arousal. The amygdala is a main candidate for the emotional area, and the hypothalamus for the corporal area, but other areas may also provide those inputs. Experimental observations that support this model are discussed, and an outline of additional experiments for validating the model is proposed. If validated, the model would provide knowledge that fills a gap in the understanding of human sexuality - knowledge that would benefit individuals, the medical profession, and society as a whole. PMID:21095066

  20. Tree of Sex: A database of sexual The Tree of Sex Consortium1

    E-print Network

    Hahn, Matthew

    Tree of Sex: A database of sexual systems The Tree of Sex Consortium1 The vast majority. Here, we describe a database developed to facilitate access to sexual system and sex chromosome of eukaryotic organisms reproduce sexually, yet the nature of the sexual system and the mechanism of sex

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

    PubMed Central

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

    2009-01-01

    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

  2. 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

  3. Sexual isolation in bacteria

    Microsoft Academic Search

    Jacek Majewski

    2001-01-01

    Bacteria exchange genes rarely but are promiscuous in the choice of their genetic partners. Inter-specific recombination has the advantage of increasing genetic diversity and promoting dissemination of novel adaptations, but suffers from the negative effect of importing potentially harmful alleles from incompatible genomes. Bacterial species experience a degree of 'sexual isolation' from genetically divergent organisms ^ recombination occurs more frequently

  4. Sexual conflict reduces offspring fitness in zebra finches.

    PubMed

    Royle, Nick J; Hartley, Ian R; Parker, Geoff A

    2002-04-18

    Parental care is often costly; hence, in sexually reproducing species where both male and female parents rear their offspring (biparental care), sexual conflict over parental investment can arise. Such conflict occurs because each care-giver would benefit from withholding parental investment for use with another partner, leading to a reduction in the amount of care given by one parent at the expense of the other. Here we report experiments to explore the prediction from theory that parents rearing offspring alone may provide greater parental investment than when rearing offspring together with a partner. We found that when the number of offspring per parent, and hence the potential workload, were kept constant, offspring received a greater per capita parental investment from single females than from both parents working together, and that males reared by single mothers were more sexually attractive as adults than their biparentally reared siblings. This difference between single- and two-parent families is due to a reduction in care provided by females when they care together with a male, rather than laziness by males or differences in the begging behaviour of chicks, supporting the claim that sexual conflict in biparental care can reduce the quality of offspring raised. PMID:11961554

  5. Sexual Health

    PubMed Central

    Hansen, Lisa; Mann, Janice; McMahon, Sharon; Wong, Thomas

    2004-01-01

    Health Issue Much attention is devoted to women's reproductive health, but the formative and mature stages of women's sexual lives are often overlooked. We have analyzed cross-sectional data from the Sexual Behaviour module of the 2000/2001 Canadian Community Health Survey (CCHS), and reviewed the literature and available indicators of the sexual health of Canadian women. Key Findings Contemporary Canadian adolescents are becoming sexually active at younger ages than in previous generations. The gender gap between young males and females in age at first intercourse has virtually disappeared. The mean age at first intercourse for CCHS respondents aged 15–24 years was between 16 and 17. Canadian-born respondents are significantly younger at first intercourse than those who were born outside of Canada. Few adolescents recognize important risks to their sexual health. Older Canadians are sexually active, and continue to find emotional and physical satisfaction in their sexual relationships. Data Gaps and Recommendations Both health surveys and targeted research must employ a broader understanding of sexuality to measure changes in and determinants of the sexual health of Canadians. There is reluctance to direct questions about sexual issues to younger Canadians, even though increased knowledge of sexual health topics is associated with delayed onset of sexual intercourse. Among adults, sex-positive resources are needed to address aspects of aging, rather than medicalizing age-related sexual dysfunction. Age and gender-appropriate sexual health care, education, and knowledge are important not only for women of reproductive age, but for Canadians at all stages of life. PMID:15345087

  6. SEXUAL ASSAULT AND SEXUAL HARASSMENT QUICK REFERENCE

    E-print Network

    Thompson, Michael

    SEXUAL ASSAULT AND SEXUAL HARASSMENT QUICK REFERENCE Sexual Assault Definition ­ any form of sexual contact without both parties' voluntary consent. Contrary to what most people think, sexual assault. ­ Zvulony & Company ­ The Law of Sexual Assault in Canada. Sexual Harassment Definition ­ is comment

  7. Diploidy and the selective advantage for sexual reproduction in unicellular organisms

    Microsoft Academic Search

    Maya Kleiman; Emmanuel Tannenbaum

    2009-01-01

    This article develops mathematical models describing the evolutionary dynamics of both asexually and sexually reproducing\\u000a populations of diploid unicellular organisms. The asexual and sexual life cycles are based on the asexual and sexual life\\u000a cycles in Saccharomyces cerevisiae, Baker’s yeast, which normally reproduces by asexual budding, but switches to sexual reproduction when stressed. The mathematical\\u000a models consider three reproduction pathways:

  8. Sexual selection vs ecological causation in a sexually dimorphic caecilian, Schistometopum thomense (Amphibia Gymnophiona Caeciliidae)

    Microsoft Academic Search

    M. Delêtre; G. J. Measey

    2004-01-01

    Determination of the proximate cause of sexual dimorphism remains difficult, especially when trying to discriminate between sexual selection and ecological causation. A clear rejection of one of these hypotheses would advance the direction of future investigations, especially for cryptic and\\/or subterranean species. Sexual dimorphism in head size, but not body size, is confirmed for Schistometopum thomense, a fossorial caecilian from

  9. Positive correlation of trophic level and proportion of sexual taxa of oribatid mites (Acari: Oribatida) in alpine soil systems.

    PubMed

    Fischer, Barbara M; Meyer, Erwin; Maraun, Mark

    2014-08-01

    We investigated community structure, trophic ecology (using stable isotope ratios; (15)N/(14)N, (13)C/(12)C) and reproductive mode of oribatid mites (Acari, Oribatida) along an altitudinal gradient (2,050-2,900 m) in the Central Alps (Obergurgl, Austria). We hypothesized that (1) the community structure changes with altitude, (2) oribatid mites span over four trophic levels, (3) the proportion of sexual taxa increases with altitude, and (4) the proportion of sexual taxa increases with trophic level, i.e. is positively correlated with the ?(15)N signatures. Oribatid mite community structure changed with altitude indicating that oribatid mites occupy different niches at different altitudes. Oribatid mites spanned over 12 ?(15)N units, i.e. about four trophic levels, which is similar to lowland forest ecosystems. The proportion of sexually reproducing taxa increased from 2,050 to 2,900 m suggesting that limited resource availability at high altitudes favors sexual reproduction. Sexual taxa more frequently occurred higher in the food web indicating that the reproductive mode is related to nutrition of oribatid mites. Generally, oribatid mite community structure changed from being decomposer dominated at lower altitude to being dominated by fungal and lichen feeders, and predators at higher altitude. This supports the view that resources from dead organic material become less available with increasing altitude forcing species to feed on living resources such as fungi, lichens and nematodes. Our findings support the hypothesis that limited resource accessibility (at high altitudes) favors sexually reproducing species whereas ample resource supply (at lower altitudes) favors parthenogenetic species. PMID:24687174

  10. 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

  11. 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

  12. Towards reproducible, scalable lateral molecular electronic devices

    NASA Astrophysics Data System (ADS)

    Durkan, Colm; Zhang, Qian

    2014-08-01

    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.

  13. 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

  14. Sexual selection

    Microsoft Academic Search

    Malte Andersson; Yoh Iwasa

    1996-01-01

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

  15. TRIDIAGONAL REPRODUCING KERNELS AND SUBNORMALITY

    E-print Network

    McGuire, Paul

    . MCGUIRE For John B. Conway, on the occasion of his retirement. Abstract. We consider analytic reproducing, subnormal operator, tridi- agonal kernel. 1 #12;2 GREGORY T. ADAMS, NATHAN S. FELDMAN, AND PAUL J. MCGUIRE, but this is not a problem for the general theory. The interested reader is referred to Adams, McGuire, and Paulsen [2

  16. Reproducibility of natural head position.

    PubMed

    Chiu, C S; Clark, R K

    1991-04-01

    The orientation of the head, when the natural head position was adopted, was measured relative to the true vertical on standardized black and white profile photographs. Two methods of obtaining the natural head position were compared and their reproducibility tested. No statistically significant difference was found between the two different methods or at different sittings. PMID:2050893

  17. 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...

  18. Comparative Transcriptional Analysis of Asexual and Sexual Morphs Reveals Possible Mechanisms in Reproductive Polyphenism of the Cotton Aphid

    PubMed Central

    Jiang, Feng; Guo, Wei; Zhou, Shu-Tang

    2014-01-01

    Aphids, the destructive insect pests in the agriculture, horticulture and forestry, are capable of reproducing asexually and sexually upon environmental change. However, the molecular basis of aphid reproductive mode switch remains an enigma. Here we report a comparative analysis of differential gene expression profiling among parthenogenetic females, gynoparae and sexual females of the cotton aphid Aphis gossypii, using the RNA-seq approach with next-generation sequencing platforms, followed by RT-qPCR. At the cutoff criteria of fold change ?2 and P<0.01, we identified 741 up- and 879 down-regulated genes in gynoparae versus parthenogenetic females, 2,101 up- and 2,210 down-regulated genes in sexual females compared to gynoparae, and 1,614 up- and 2,238 down-regulated genes in sexual females relative to parthenogenetic females. Gene ontology category and KEGG pathway analysis suggest the involvement of differentially expressed genes in multiple cellular signaling pathways into the reproductive mode transition, including phototransduction, cuticle composition, progesterone-mediated oocyte maturation and endocrine regulation. This study forms a basis for deciphering the molecular mechanisms underlying the shift from asexual to sexual reproduction in the cotton aphid. It also provides valuable resources for future studies on this host-alternating aphid species, and the insight into the understanding of reproductive mode plasticity in different aphid species. PMID:24915491

  19. Sexual Problems

    MedlinePLUS Videos and Cool Tools

    ... include hormone therapy, antidepressants, phosphodiesterase inhibitors, which are drugs often used for erectile dysfunction, and other medications. ... may improve sexual function. A group of antidepressant drugs called selective serotonin reuptake inhibitors, or SSRIs, often ...

  20. Sexual Health

    MedlinePLUS

    ... sexual intimacy all play a role in healthy relationships. They also contribute to your sense of well-being. A number of disorders can affect the ability to have or enjoy sex in both men and women. Factors that can ...

  1. 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

  2. SEXUAL MISCONDUCT/SEXUAL ASSAULT POLICY

    E-print Network

    Dennett, Daniel

    SEXUAL 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 harassment, sex/gender discrimination, sexual assault, rape and other gender-based misconduct, through

  3. Detecting sexual conflict and sexually antagonistic coevolution

    E-print Network

    Day, Troy

    Detecting sexual conflict and sexually antagonistic coevolution Locke Rowe1,2,* and Troy Day3,4 1 by providing an operational definition of sexual conflict that applies to both inter- and intralocus conflict approaches for detecting interlocus sexual conflict and resultant sexually antagonistic coevolution. We

  4. Healthy Aging -- Sexual Health

    MedlinePLUS

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

  5. Improving the reproducibility of pyrolysis MS techniques

    SciTech Connect

    Roussis, S.G.; Fedora, J.W. [Imperial Oil, Sarnia (Canada)

    1995-12-31

    The analysis of the majority of volatile samples is primarily accomplished with established techniques (EI, CI). These techniques are based on the direct vapourization of the sample, upon heating, in the ionization source of a mass spectrometer. Typical analytical techniques, able to analyze non-volatile samples are those that allow the desorption of components from the solid or liquid phase directly to the gas phase. Field Desorption (FD) and Desorption Chemical Ionization (DCI) are two of these techniques. Fast Atom Bombardment (FAB) has been more successful in analyzing polar samples than non-volatile hydrocarbon samples. Limited information is available for the capabilities of the newer ionization techniques (Electrospray Ionization, ESI; Matrix Assisted Laser Desorption Ionization, MALDI) to characterize the non-volatile hydrocarbon samples. ESI of mixtures of compounds produces complex mass spectra, consisting of multiply charged ion species, that may be difficult to interpret. MALDI has the potential for ionization of non-volatile hydrocarbon samples, but extensive research is required to determine the appropriate matrix compounds that will permit the unbiased desorption of all sample components. An important requirement in the characterization of the non-volatile samples using direct desorption techniques without prior chromatographic separation, is the use of ultra high resolution (>50,000), for the separation of high molecular weight isobaric peaks. In the present work, the experimental parameters affecting reproducibility have been studied, optimum conditions have been determined that permit reproducible analysis.

  6. The Evolution of Sex Asexual v. Sexual Reproduction

    E-print Network

    Dever, Jennifer A.

    1 The Evolution of Sex Asexual v. Sexual Reproduction In a game between asexual and sexual reproduction, asexual reproduction always wins -- other things being equal. Hamilton's computer model of reproduction: Asexual Reproduction · Binary fission - The method by which bacteria reproduce. The circular DNA

  7. Interference of asexual and sexual reproduction in the green hydra

    Microsoft Academic Search

    Anita Kaliszewicz

    2011-01-01

    The green hydra, Hydra viridissima, has three sexes: hermaphrodite, male, and female. I investigated the reproductive strategies of the green hydra and the\\u000a relationship between asexual budding and sexual reproduction. The proportion of mature individuals in the asexually reproducing\\u000a population increased with increasing temperature. Sexual reproduction did not interrupt asexual budding in hermaphrodites\\u000a or males; sexual reproduction did interrupt asexual

  8. Psychology/Zoology 310: Human Sexuality Summer 2013 Instructor: Marc Breedlove; 240 Giltner; 355-1749; breedsm@msu.edu

    E-print Network

    Liu, Taosheng

    Psychology/Zoology 310: Human Sexuality Summer 2013 ONLINE Instructor: Marc Breedlove; 240 Giltner Evolution: Ch 2 What does sexual reproduction accomplish? Why is sexual reproduction so pervasive among vertebrates? What is sexual selection and how has it shaped our species? Human sexual anatomy Ch 3 & 4

  9. Student Sexual Misconduct Policy

    E-print Network

    Huang, Jianyu

    Student Sexual Misconduct Policy 2014-2015 #12;1 BOSTON COLLEGE STUDENT SEXUAL MISCONDUCT POLICY INDEX I. INTRODUCTION II. BUILDING AN EDUCATIONAL ENVIRONMENT FREE FROM SEXUAL MISCONDUCT III. PROHIBITED BEHAVIOR a. Definitions i. Sexual Misconduct ii. Sexual Harassment iii. Sexual Assault iv. Consent

  10. 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…

  11. 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)

  12. 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

  13. Quantizations from reproducing kernel spaces

    SciTech Connect

    Twareque Ali, S., E-mail: stali@mathstat.concordia.ca [Department of Mathematics and Statistics, Concordia University, Montréal, Québec, Canada H3G 1M8 (Canada); Bagarello, F., E-mail: fabio.bagarello@unipa.it [Dieetcam, Facoltà di Ingegneria, Università di Palermo, I-90128 Palermo (Italy); Pierre Gazeau, Jean, E-mail: gazeau@apc.univ-paris7.fr [Laboratoire APC, Université Paris 7-Denis Diderot, 10, rue A. Domon et L. Duquet, 75205 Paris Cedex 13 (France)

    2013-05-15

    The purpose of this work is to explore the existence and properties of reproducing kernel Hilbert subspaces of L{sup 2}(C,d{sup 2}z/?) based on subsets of complex Hermite polynomials. The resulting coherent states (CS) form a family depending on a nonnegative parameter s. We examine some interesting issues, mainly related to CS quantization, like the existence of the usual harmonic oscillator spectrum despite the absence of canonical commutation rules. The question of mathematical and physical equivalences between the s-dependent quantizations is also considered. -- Highlights: ? We discuss in detail an interesting decomposition of L{sup 2}, in terms of ladder operators. ? We consider coherent states on this structure and we use them for quantization. ? We show how this structure is related with non hermitian quantum mechanics. ? We consider the relation between different schemes of quantizations.

  14. Teenage Sexuality

    MedlinePLUS

    ... be ready to have sexual intercourse? Will having sex help my relationship? If I am attracted to a same-sex ... parents about your family's values. Waiting to have sex until you are older, in a serious relationship, and able to accept the responsibilities that come ...

  15. Sexuality I. Sexual Orienta0on

    E-print Network

    Dever, Jennifer A.

    1 Sexuality I. Sexual Orienta0on II. Hormones & cogni0on III. The Female sexual Behavior of the Human Female (1953) by A. Kinsey #12;2 II. Hormones, Cogni0on & Learning A and female-typical sexual behaviors in vertebrates 1. Testosterone ­ Posi0ve rela0onship

  16. The reproducibility of patch tests.

    PubMed

    Bourke, J F; Batta, K; Prais, L; Abdullah, A; Foulds, I S

    1999-01-01

    There is conflicting evidence regarding the reproducibility of patch testing. Discordant results have been reported in up to 44% of cases. The clinical relevance of these discordant patch tests has not been previously assessed. We studied 383 consecutive patients receiving simultaneous duplicate patch testing on opposite sides of the upper back with 10 allergens from the European standard series. Completely discordant patch tests-a negative test on one side with a positive test on the opposite side-were recorded in 30 (8%) patients. Two patients had discordant tests to two of the allergens; 28 had discordant reactions to one allergen. Completely discordant tests were recorded for nickel in 10 (3%) patients, balsam of Peru in two (0.5%), thiomersal in one (0.3%), cobalt in four (1%), paraphenylenediamine in three (0.8%), fragrance mix in two (0.5%), formaldehyde in four (1%), potassium dichromate in two (0.5%), lanolin in three (0.8%) and Kathon CG in one (0.3%). Of those patients with completely discordant patch tests, the allergen was deemed to be a true positive in 11 (3% of total) cases and of possible relevance in a further three. The allergen was felt to be relevant to the presenting complaint in seven (2% of total) patients. PMID:10215776

  17. Evolutionary inevitability of sexual antagonism

    PubMed Central

    Connallon, Tim; Clark, Andrew G.

    2014-01-01

    Sexual antagonism, whereby mutations are favourable in one sex and disfavourable in the other, is common in natural populations, yet the root causes of sexual antagonism are rarely considered in evolutionary theories of adaptation. Here, we explore the evolutionary consequences of sex-differential selection and genotype-by-sex interactions for adaptation in species with separate sexes. We show that sexual antagonism emerges naturally from sex differences in the direction of selection on phenotypes expressed by both sexes or from sex-by-genotype interactions affecting the expression of such phenotypes. Moreover, modest sex differences in selection or genotype-by-sex effects profoundly influence the long-term evolutionary trajectories of populations with separate sexes, as these conditions trigger the evolution of strong sexual antagonism as a by-product of adaptively driven evolutionary change. The theory demonstrates that sexual antagonism is an inescapable by-product of adaptation in species with separate sexes, whether or not selection favours evolutionary divergence between males and females. PMID:24335980

  18. Recycling parental sexual messages.

    PubMed

    Darling, C A; Hicks, M W

    1983-01-01

    The purpose of this study was to explore parent-child sexual communication by investigating the impact of direct and indirect parental messages on the sexual attitudes and sexual satisfaction of young adults. A survey research design was used to obtain data from undergraduate students attending a large Southern university. The findings indicate that both direct and indirect parental sexual messages are negative and restrictive and have a differential impact on sexual satisfaction and sexual attitudes. While sexual satisfaction was positive, sexual attitudes were found to be problematic, especially among females. Suggestions are given for approaches that family life educators and parents may use in order to recycle previous sexual messages. PMID:6631981

  19. Sexual assault.

    PubMed

    1997-11-01

    This document provides information on issues related to sexual assault in the US. The specific topics briefly discussed are incidence, psychological impact, assault assessment kits, medical evaluation, legal concerns, counseling, follow-up, and special circumstances. It is stated that a woman who is sexually assaulted would experience intense anxiety, anger or fear, and rape-trauma syndrome. The physician evaluating the victim should be aware of the state statutory requirements, which may involve the use of kits for gathering evidence. Informed consent from the victim and meticulous physical examination of the entire body should be performed with photographs and drawings made in the injured areas. In counseling, the physician should talk with the patient concerning the degree of the injury and the probability of infection or pregnancy. There is a need for patients to be reevaluated concerning her medical and psychological status. PMID:12295376

  20. Population genetic structure of diploid sexual and polyploid apomictic hawthorns (Crataegus; Rosaceae) in the Pacific Northwest.

    PubMed

    Lo, Eugenia Y Y; Stefanovi?, Sasa; Dickinson, Timothy A

    2009-03-01

    Polyploidy and gametophytic apomixis are two important and associated processes in plants. Many hawthorn species are polyploids and can reproduce both sexually and apomictically. However, the population genetic structure of these species is poorly understood. Crataegus douglasii is represented exclusively by self-compatible tetraploid pseudogamous apomicts across North America, whereas Crataegus suksdorfii found in the Pacific Northwest is known to include self-incompatible diploid sexuals as well as polyploid apomicts. We compare population structure and genetic variability in these two closely related taxa using microsatellite and chloroplast sequence markers. Using 13 microsatellite loci located on four linkage groups, 251 alleles were detected in 239 individuals sampled from 15 localities. Within-population multilocus genotypic variation and molecular diversity are greatest in diploid sexuals and lowest in triploid apomicts. Apart from the isolation of eastern North American populations of C. douglasii, there is little evidence of isolation by distance in this taxon. Genetic diversity in western populations of C. douglasii suggests that gene flow is frequent, and that colonization and establishment are often successful. In contrast, local populations of C. suksdorfii are more markedly differentiated. Gene flow appears to be limited primarily by distance in diploids and by apomixis and self-compatibility in polyploids. We infer that apomixis and reproductive barriers between cytotypes are factors that reduce the frequency of gene flow among populations, and may ultimately lead to allopatric speciation in C. suksdorfii. Our findings shed light on evolution in woody plants that show heterogeneous ploidy levels and reproductive systems. PMID:19243504

  1. A cumulative scale of severe sexual sadism.

    PubMed

    Nitschke, Joachim; Osterheider, Michael; Mokros, Andreas

    2009-09-01

    The article assesses the scale properties of the criterion set for severe sexual sadism in a sample of male forensic patients (N = 100). Half of the sample consists of sexual sadists; the remainder is sampled at random from the general group of nonsadistic sex offenders. Eleven of 17 criteria (plus the additional item of inserting objects into the victim's bodily orifices) of Marshall, Kennedy, Yates, and Serran's list form a cumulative scale. More specifically, this scale comprises all the 5 core criteria that Marshall and his colleagues considered particularly relevant. The resulting 11-item scale of severe sexual sadism is highly reliable (r(tt) = .93) and represents a strong scale (H = .83) of the Guttman type (coefficient of reproducibility = .97). The 11-item scale distinguishes perfectly between sexual sadists and nonsadistic sex offenders in the sample. PMID:19605691

  2. Variable sexual ornaments in scarlet-tufted malachite sunbirds ( Nectarinia johnstoni) on Mount Kenya

    Microsoft Academic Search

    Matthew R. Evans; Phoebe Barnard

    1995-01-01

    In order to be elaborated by sexual selection, sexual ornaments must vary perceptibly and genetically among individuals in natural populations. Rather little is known about ornament variation in monogamous species, in which sexual selection should act more weakly than in polygynous species. We report phenotypic variation in feather ornament size (elongated tails and pectoral tufts) and body size in the

  3. Sexually selected females in the monogamous Western Australian seahorse

    PubMed Central

    Kvarnemo, Charlotta; Moore, Glenn I; Jones, Adam G

    2006-01-01

    Studies of sexual selection in monogamous species have hitherto focused on sexual selection among males. Here, we provide empirical documentation that sexual selection can also act strongly on females in a natural population with a monogamous mating system. In our field-based genetic study of the monogamous Western Australian seahorse, Hippocampus subelongatus, sexual selection differentials and gradients show that females are under stronger sexual selection than males: mated females are larger than unmated ones, whereas mated and unmated males do not differ in size. In addition, the opportunity for sexual selection (variance in mating success divided by its mean squared) for females is almost three times that for males. These results, which seem to be generated by a combination of a male preference for larger females and a female-biased adult sex ratio, indicate that substantial sexual selection on females is a potentially important but under-appreciated evolutionary phenomenon in monogamous species. PMID:17476772

  4. Sexual function, sexual abuse and sexually transmitted diseases in adolescence

    Microsoft Academic Search

    Margaret J. Blythe

    2003-01-01

    As adolescents progress through puberty, many biological changes occur and, for young women, this includes the onset of menses and the capability for reproduction. During this time, sexual identity is developed and expressions of sexuality become more frequent. Adolescent women engage in a variety of sexual behaviours, both non-coital and coital. As teens begin dating relationships, they are at risk

  5. Your Sexual Health

    MedlinePLUS

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

  6. Men and Sexual Trauma

    MedlinePLUS

    ... in women. Who are the perpetrators of male sexual assault? Those who sexually assault men or boys differ ... male gender socialization affect the recognition of male sexual assault? Men who have not dealt with the symptoms ...

  7. Military Sexual Trauma

    MedlinePLUS

    ... used by VA to refer to experiences of sexual assault or repeated, threatening sexual harassment that a Veteran ... make an estimate of the actual rates of sexual assault and harassment experiences among all individuals serving in ...

  8. Narrative Sexual Identity Therapy

    Microsoft Academic Search

    Mark A. Yarhouse

    2008-01-01

    Sexual identity therapy is an alternative to the two polarized positions of sexual reorientation therapy and gay-integrative therapy for clients who present with sexual identity concerns. This alternative model focuses on sexual identity—the private and public acts of identifying and communicating one's sexual preferences—and how the decision to do so is informed by dominant stories about what sexual attractions mean

  9. Proximate developmental mediators of sexual dimorphism in size: case studies from squamate reptiles

    Microsoft Academic Search

    Henry B. John-Alder; Robert M. Cox; Emily N. Taylor

    2007-01-01

    Synopsis Sexual dimorphism in size (sexual size dimorphism; SSD) is nearly ubiquitous, but the relative importance of genetic versus environmental control of SSD is not known for most species. We investigated proximate determinants of SSD in several species of squamate reptiles, including three species of Sceloporus lizards and the diamond-backed rattlesnake (Crotalus atrox). In natural populations of these species, SSD

  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. 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

  12. 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

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

    PubMed Central

    Darden, Safi K.; Watts, Lauren

    2012-01-01

    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

  14. Sexual orientation and consistency of sexual identity.

    PubMed

    McConaghy, N; Armstrong, M S

    1983-08-01

    The semantic confusion in the use of the terms sexual and gender identity and role is discussed. Theories concerning the development of the sense of sexual identity in normals have been based largely on the sense of sexual identity in sexually deviant subjects. It is suggested that such subjects may have a stronger and more consistent sense of sexual identity than subjects unaware of sexually deviant impulses. Male medical students in two consecutive years anonymously completed a questionnaire concerning their sexual orientation, preference, role, and identity. In both years, students aware of a homosexual component answered the items investigating their sexual identity with greater consistency than did the students unaware of a homosexual component. PMID:6639327

  15. Assessment of sexual function in women with pelvic floor dysfunction.

    PubMed

    Kammerer-Doak, Dorothy

    2009-05-01

    This article reviews sexual function questionnaires used in urogynecology, impact of pelvic floor dysfunction (PFD) on sexual function, and impact of surgical treatment of PFD on sexual function, with a focus on the experience and publications of validated sexual function questionnaires in the urogynecologic literature. A review of the literature was performed to obtain data on sexual function and PFD focusing on those studies that utilized validated sexual function questionnaires. Validated questionnaires assure data that are reliable, quantifiable, and reproducible. Quality-of-life questionnaires, such as The King's Health Questionnaire and the Incontinence Impact Questionnaire, include a few questions addressing sexual function but really deal with the overall impact of incontinence and/or prolapse on the patient's QOL or well-being and do not focus on sexual function. General questionnaires focused on sexual function include the Female Sexual Function Index and the Sexual History Form 12, which were designed to evaluate sexual function and have undergone validation and reliability testing in a general population. General questionnaires are not condition-specific and may not be sensitive enough to detect differences due to PFD. The Pelvic Organ Prolapse Urinary Incontinence Sexual Questionnaire (PISQ) is a condition-specific questionnaire focused on sexual function for use in women with PFD and has undergone rigorous validation and reliability testing. Many recent publications examining the impact of urinary incontinence (UI), fecal incontinence, and pelvic organ prolapse (POP) using validated generalized and disease-specific questionnaires have reported poorer sexual function in women with PFD. The PISQ has been used most commonly to evaluate sexual function after surgery for PFD, with increased PISQ scores in approximately 70%. Significant improvement is noted for sexual function related to physical and partner-related factors, with no changes for orgasm, desire, or arousal after surgical repair of PFD. Studies which used generalized sexual function questionnaires mainly found no change in sexual function following surgical treatment of POP and/or UI. In summary, the use of validated questionnaires shows that PFD is associated with a negative impact on sexual functions. Surgical correction of POP and/or UI improves sexual function in approximately 70% of patients, although some studies show no change with the use of non-condition-specific questionnaires. PMID:19440782

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

    E-print Network

    VandeVord, Pamela

    of rape or attempted rape between the age of 14 and 25 ! 9 out of 10 date rapes are not reported ! Women the Terms Sexual Assault #Sexual activity, including but not limited to rape, attempted rape or oral sex, guilt) $ Date rape, a form of sexual assault, is rape by someone the victim is dating. $ Acquaintance

  17. Detecting sexual conflict and sexually antagonistic coevolution

    Microsoft Academic Search

    Locke Rowe; Troy Day

    2006-01-01

    We begin by providing an operational definition of sexual conflict that applies to both inter- and intralocus conflict. Using this definition, we examine a series of simple coevolutionary models to elucidate fruitful approaches for detecting interlocus sexual conflict and resultant sexually antagonistic coevolution. We then use published empirical examples to illustrate the utility of these approaches. Three relevant attributes emerge.

  18. Sexual coercion and the misperception of sexual intent

    Microsoft Academic Search

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

    2008-01-01

    Misperceiving a woman's platonic interest as sexual interest has been implicated in a sexual bargaining process that leads to sexual coercion. This paper provides a comprehensive review of sexual misperception, including gender differences in perception of women's sexual intent, the relationship between sexual coercion and misperception, and situational factors that increase the risk that sexual misperception will occur. Compared to

  19. Reproducible Measurements of MPI Performance Characteristics

    Microsoft Academic Search

    William Gropp; Ewing L. Lusk

    1999-01-01

    In this paper we describe the diculties inherent in making accurate, reproducible measurements of message-passing performance. We describe some of the mistakes often made in attempting such mea- surements and the consequences of such mistakes. We describe mpptest, a suite of performance measurement programs developed at Argonne National Laboratory, that attempts to avoid such mistakes and obtain reproducible measures of

  20. Reproducibility of Genucom knee analysis system testing

    Microsoft Academic Search

    Randall R. Wroble; Edward S. Grood; Frank R. Noyes; David J. Schmitt

    1990-01-01

    The Genucom knee analysis system was studied to determine the reproducibility of test results. In the first phase of the study we investigated the reproducibility of anterior\\/posterior stress tests at 30° and 90° of flexion and varus\\/valgus stress tests at 20° of flexion in 10 control subjects during three seatings on 3 sep arate days. In the second phase we

  1. Alcohol and Sexual Assault

    Microsoft Academic Search

    Antonia Abbey; Tina Zawacki; Philip O. Buck; A. Monique Clinton; Pam McAuslan

    2001-01-01

    Conservative estimates of sexual assault prevalence suggest that 25 percent of American women have experienced sexual assault, including rape. Approximately one-half of those cases involve alcohol consumption by the perpetrator, victim, or both. Alcohol contributes to sexual assault through multiple pathways, often exacerbating existing risk factors. Beliefs about alcohol's effects on sexual and aggressive behavior, stereotypes about drinking women, and

  2. SEXUALITY AND GENDER IDENTITY

    E-print Network

    Viglas, Anastasios

    LEARN TO UNDERSTAND SEXUALITY AND GENDER IDENTITY COUNSELLING AND PSYCHOLOGICAL SERVICES CAPS #12;CONTENTS 01 Questioning your sexuality or gender identity 02 Coming out 04 Sexual health 05 Harassment and discrimination 06 Types of support and information available 08 Useful resources Sexual orientation is about who

  3. [Endocrine therapy of sexual impotence in men].

    PubMed

    Giorgi, P M; Turchi, P; Canale, D; Menchini Fabris, G F

    1992-09-01

    Male sexual activity is in all mammalian species, included man, androgen-dependent. The role of testosterone (T) starts already during intrauterine life. It continues thereafter, inducing the development of sexual secondary characteristics and libido. Therefore T has represented the "classical" treatment of male sexual dysfunctions. In the therapeutic routinary use T is employed ad ester, like cipionate, enanthate and other i.m., undecanoate per os. When a pituitary defect is present and the testicular receptors are functioning a treatment with HCG can be employed. PMID:1439849

  4. Regulation of apomixis: learning from sexual experience.

    PubMed

    Rodriguez-Leal, Daniel; Vielle-Calzada, Jean-Philippe

    2012-11-01

    Apomixis is a natural form of asexual reproduction through seeds that leads to viable offspring genetically identical to the mother plant. New evidence from sexual model species indicates that the regulation of female gametogenesis and seed formation is also directed by epigenetic mechanisms that are crucial to control events that distinguish sexuality from apomixis, with important implications for our understanding of the evolutionary forces that shape structural variation and diversity in plant reproduction. PMID:23000434

  5. Sexual selection and natural selection in bird speciation

    PubMed Central

    Price, T.

    1998-01-01

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

  6. Sexual anxiety and female sexual arousal: A comparison of arousal during sexual anxiety stimuli and sexual pleasure stimuli

    Microsoft Academic Search

    Vicki E. Beggs; Karen S. Calhoun; Sharlene A. Wolchik

    1987-01-01

    Sexual arousal occurring during sexual anxiety stimuli was compared to sexual arousal occurring during sexual pleasure stimuli in 19 sexually functional women. Stimuli were individualized narratives based on descriptions given by each subject. Sexual arousal was measured by monitoring vaginal blood flow with a vaginal photoplethysmograph. Results showed significant increases in vaginal blood flow in response to both sexual anxiety

  7. 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

  8. Sexual compatibility and the sexual desire-motivation relation in females with hypoactive sexual desire disorder.

    PubMed

    Hurlbert, D F; Apt, C; Hurlbert, M K; Pierce, A P

    2000-07-01

    Fifty-four female participants with hypoactive sexual desire disorder supplied daily reports of their sexual desire and motivation. The relation between desire and motivation remained statistically significant when controlling for sexual compatibility, sexual stress, sexual fantasy, and marital and sexual satisfaction. Findings suggest that (a) women higher in sexual compatibility experience greater sexual motivation regardless of their marital and sexual satisfaction, their sexual desire intensity, and depressive symptomatology; and (b) the relation between sexual compatibility and sexual desire is mediated by the propensity of those women high in sexual compatibility to have greater marital and sexual satisfaction. Within-subject analyses that controlled for autocorrelation and linear trends in the time series revealed that 40% of the women experienced significantly higher sexual motivation on greater sexual desire days. A discussion of these findings and evidence for the addition of sexual motivation as a distinct phase in the human sexual response cycle are explored. PMID:10881380

  9. SPECIES AND What is a species?

    E-print Network

    Rose, Michael R.

    times #12;Habitat/Spatial Isolation Occupy different habitats in the same area #12;Behavioral Isolation to classify species #12;How do species form? When a group of individuals remains isolated from the rest of its the main group? #12;Geographical Isolation Physical barrier #12;Temporal Isolation Reproduce at different

  10. Numerical reproducibility for implicit Monte Carlo simulations

    SciTech Connect

    Cleveland, M.; Brunner, T.; Gentile, N. [Lawrence Livermore National Laboratory, P. O. Box 808, Livermore CA 94550 (United States)

    2013-07-01

    We describe and compare different approaches for achieving numerical reproducibility in photon Monte Carlo simulations. Reproducibility is desirable for code verification, testing, and debugging. Parallelism creates a unique problem for achieving reproducibility in Monte Carlo simulations because it changes the order in which values are summed. This is a numerical problem because double precision arithmetic is not associative. In [1], a way of eliminating this roundoff error using integer tallies was described. This approach successfully achieves reproducibility at the cost of lost accuracy by rounding double precision numbers to fewer significant digits. This integer approach, and other extended reproducibility techniques, are described and compared in this work. Increased precision alone is not enough to ensure reproducibility of photon Monte Carlo simulations. A non-arbitrary precision approaches required a varying degree of rounding to achieve reproducibility. For the problems investigated in this work double precision global accuracy was achievable by using 100 bits of precision or greater on all unordered sums which where subsequently rounded to double precision at the end of every time-step. (authors)

  11. Peering through the looking glass at a sexual parasite: are Amazon mollies red queens?

    PubMed

    Dries, Laurie A

    2003-06-01

    The gynogenetic Amazon molly (Poecilia formosa) is a clonal, all-female lineage of livebearing fish that faces an unusual obstacle to evolutionary persistence. Sperm from heterospecific males (either sailfin, P. latipinna, or Atlantic, P. mexicana, mollies) is necessary to trigger embryogenesis. However, none of the male's genes are incorporated into the genome of the gynogenetic offspring. Some investigators have proposed that the evolution of male mate discrimination is a result of this cost, leading to a coevolutionary arms race between male avoidance of P. formosa and P. formosa attractiveness. Given that P. formosa successfully reproduces and has not yet gone extinct, it is clear there are mechanisms by which they attract the sexual attention of males. Although a Red Queen coevolutionary process in typical host/parasite systems has been shown to favor the persistence of sexual species, in this system an arms race has been invoked to explain the reverse. Here I present behavioral data supporting a more parsimonious scenario: that mechanisms of attraction in P. formosa are simply a consequence of its hybrid origin. Poecilia latipinna and P. mexicana males do not discriminate between gynogenetic P. formosa females and first generation sexual hybrid females, and females do not differ in agonistic behaviors associated with competition for mates. Both results contradict predictions from the Red Queen hypothesis. Therefore, coevolution is not necessary to explain the apparent evolutionary persistence of P. formosa. PMID:12894946

  12. 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

  13. The Economics of Reproducibility in Preclinical Research.

    PubMed

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

    2015-06-01

    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. Hormones and History: The Evolution and Development of Primate Female Sexuality

    PubMed Central

    Wallen, Kim; Zehr, Julia L.

    2005-01-01

    Sexual behavior is required for reproduction in internally fertilizing species but poses significant social and physical risks. Females in many nonprimate species have evolved physical and behavioral mechanisms restricting sexual behavior to when females are fertile. The same hormones producing female fertility also control these mechanisms, assuring that sex only occurs when reproduction is possible. In contrast to nonprimate mammals, hormones do not regulate the capacity to engage in sex in female anthropoid primates, uncoupling fertility and the physical capacity to mate. Instead, in primates, sexual motivation has become the primary coordinator between sexual behavior and fertility. This dependence upon psychological mechanisms to coordinate physiology with behavior is possibly unique to primates, including humans, and allows a variety of nonphysiological influences, particularly social context, to regulate sexual behavior. The independence between hormonal state and sexual behavior allows sex to be used for social purposes. This complex regulation of primate sexuality develops during adolescence, where female monkeys show both hormonally influenced sexual motivation and socially modulated sexual behavior. We present findings from rhesus monkeys illustrating how social context and hormonal state interact to modulate adolescent and adult sexuality. It is argued that this flexibility in sexual behavior, combined with a tight regulation of sexual motivational systems by reproductive hormones, allows sexual behavior to be used for nonreproductive purposes while still assuring its occurrence during periods of female fertility. The evolutionary pressures that produced such flexibility in sexual behavior remain puzzling, but may reflect the importance of sexuality to primate social attraction and cohesion. PMID:15216429

  15. Effects of clonality on the genetic variability of rare, insular species: the case of Ruta microcarpa from the Canary Islands

    PubMed Central

    Meloni, M; Reid, A; Caujapé-Castells, J; Marrero, Á; Fernández-Palacios, J M; Mesa-Coelo, R A; Conti, E

    2013-01-01

    Many plant species combine sexual and clonal reproduction. Clonal propagation has ecological costs mainly related to inbreeding depression and pollen discounting; at the same time, species able to reproduce clonally have ecological and evolutionary advantages being able to persist when conditions are not favorable for sexual reproduction. The presence of clonality has profound consequences on the genetic structure of populations, especially when it represents the predominant reproductive strategy in a population. Theoretical studies suggest that high rate of clonal propagation should increase the effective number of alleles and heterozygosity in a population, while an opposite effect is expected on genetic differentiation among populations and on genotypic diversity. In this study, we ask how clonal propagation affects the genetic diversity of rare insular species, which are often characterized by low levels of genetic diversity, hence at risk of extinction. We used eight polymorphic microsatellite markers to study the genetic structure of the critically endangered insular endemic Ruta microcarpa. We found that clonality appears to positively affect the genetic diversity of R. microcarpa by increasing allelic diversity, polymorphism, and heterozygosity. Moreover, clonal propagation seems to be a more successful reproductive strategy in small, isolated population subjected to environmental stress. Our results suggest that clonal propagation may benefit rare species. However, the advantage of clonal growth may be only short-lived for prolonged clonal growth could ultimately lead to monoclonal populations. Some degree of sexual reproduction may be needed in a predominantly clonal species to ensure long-term viability. PMID:23789068

  16. Reproducibility and uncertainty of wastewater turbidity measurements.

    PubMed

    Joannis, C; Ruban, G; Gromaire, M-C; Chebbo, G; Bertrand-Krajewski, J-L; Joannis, C; Ruban, G

    2008-01-01

    Turbidity monitoring is a valuable tool for operating sewer systems, but it is often considered as a somewhat tricky parameter for assessing water quality, because measured values depend on the model of sensor, and even on the operator. This paper details the main components of the uncertainty in turbidity measurements with a special focus on reproducibility, and provides guidelines for improving the reproducibility of measurements in wastewater relying on proper calibration procedures. Calibration appears to be the main source of uncertainties, and proper procedures must account for uncertainties in standard solutions as well as non linearity of the calibration curve. With such procedures, uncertainty and reproducibility of field measurement can be kept lower than 5% or 25 FAU. On the other hand, reproducibility has no meaning if different measuring principles (attenuation vs. nephelometry) or very different wavelengths are used. PMID:18520026

  17. Sexual conflict and mating systems in the dorvilleid genus Ophryotrocha and the dinophilid genus Dinophilus

    Microsoft Academic Search

    Gabriella Sella; Liliana Ramella

    1999-01-01

    Predictions of mating system and sexual conflict theory are applied to mating systems of the best studied among the simultaneously hermaphroditic, sequentially hermaphroditic and gonochoric species of the dorvilleid genus Ophryotrocha and of two species of dinophilids. In the hermaphroditic Ophryotrocha species, the mating system is characterized by pair mating, absence of sperm competition and exchange of sexual roles between

  18. Sexual selection enables long-term coexistence despite ecological equivalence.

    PubMed

    M'Gonigle, Leithen K; Mazzucco, Rupert; Otto, Sarah P; Dieckmann, Ulf

    2012-04-26

    Empirical data indicate that sexual preferences are critical for maintaining species boundaries, yet theoretical work has suggested that, on their own, they can have only a minimal role in maintaining biodiversity. This is because long-term coexistence within overlapping ranges is thought to be unlikely in the absence of ecological differentiation. Here we challenge this widely held view by generalizing a standard model of sexual selection to include two ubiquitous features of populations with sexual selection: spatial variation in local carrying capacity, and mate-search costs in females. We show that, when these two features are combined, sexual preferences can single-handedly maintain coexistence, even when spatial variation in local carrying capacity is so slight that it might go unnoticed empirically. This theoretical study demonstrates that sexual selection alone can promote the long-term coexistence of ecologically equivalent species with overlapping ranges, and it thus provides a novel explanation for the maintenance of species diversity. PMID:22466286

  19. Optimal Seeding of Self-Reproducing Systems

    Microsoft Academic Search

    Amor A. Menezes; Pierre T. Kabamba

    2011-01-01

    This article is motivated by the need to minimize the number of elements required to establish a self-reproducing system. One such system is a self-reproducing extraterrestrial robotic colony, which reduces the launch payload mass for space exploration compared to current mission configurations. In this work, self-reproduction is achieved by the actions of a robot on available resources. An important consideration

  20. Convergent evolution of sexual shape dimorphism in Diptera.

    PubMed

    Bonduriansky, Russell

    2006-05-01

    Several patterns of sexual shape dimorphism, such as male body elongation, eye stalks, or extensions of the exoskeleton, have evolved repeatedly in the true flies (Diptera). Although these dimorphisms may have evolved in response to sexual selection on male body shape, conserved genetic factors may have contributed to this convergent evolution, resulting in stronger phenotypic convergence than might be expected from functional requirements alone. I compared phenotypic variation in body shape in two distantly related species exhibiting sexually dimorphic body elongation: Prochyliza xanthostoma (Piophilidae) and Telostylinus angusticollis (Neriidae). Although sexual selection appears to act differently on male body shape in these species, they exhibited strikingly similar patterns of sexual dimorphism. Likewise, patterns of within-sex shape variation were similar in the two species, particularly in males: relative elongation of the male head capsule, antenna, and legs was associated with reduced head capsule width and wing length, but was nearly independent of variation in thorax length. However, the two species presented contrasting patterns of static allometry: male sexual traits exhibited elevated allometric slopes in T. angusticollis, but not in P. xanthostoma. These results suggest that a shared pattern of covariation among traits may have channeled the evolution of sexually dimorphic body elongation in these species. Nonetheless, static allometries may have been shaped by species-specific selection pressures or genetic architectures. PMID:16477603

  1. 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

  2. Alcohol and Sexual Assault

    PubMed Central

    Abbey, Antonia; Zawacki, Tina; Buck, Philip O.; Clinton, A. Monique; McAuslan, Pam

    2015-01-01

    Conservative estimates of sexual assault prevalence suggest that 25 percent of American women have experienced sexual assault, including rape. Approximately one-half of those cases involve alcohol consumption by the perpetrator, victim, or both. Alcohol contributes to sexual assault through multiple pathways, often exacerbating existing risk factors. Beliefs about alcohol’s effects on sexual and aggressive behavior, stereotypes about drinking women, and alcohol’s effects on cognitive and motor skills contribute to alcohol-involved sexual assault. Despite advances in researchers’ understanding of the relationships between alcohol consumption and sexual assault, many questions still need to be addressed in future studies. PMID:11496965

  3. Alcohol and sexual assault.

    PubMed

    Abbey, A; Zawacki, T; Buck, P O; Clinton, A M; McAuslan, P

    2001-01-01

    Conservative estimates of sexual assault prevalence suggest that 25 percent of American women have experienced sexual assault, including rape. Approximately one-half of those cases involve alcohol consumption by the perpetrator, victim, or both. Alcohol contributes to sexual assault through multiple pathways, often exacerbating existing risk factors. Beliefs about alcohol's effects on sexual and aggressive behavior, stereotypes about drinking women, and alcohol's effects on cognitive and motor skills contribute to alcohol-involved sexual assault. Despite advances in researchers' understanding of the relationships between alcohol consumption and sexual assault, many questions still need to be addressed in future studies. PMID:11496965

  4. 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.

  5. WHY DO MOST TROPICAL ANIMALS REPRODUCE SEASONALLY? TESTING HYPOTHESES ON AN AUSTRALIAN SNAKE

    Microsoft Academic Search

    G. P. Brown; R. Shine

    2006-01-01

    Most species reproduce seasonally, even in the tropics where activity occurs year-round. Squamate reptiles provide ideal model organisms to clarify the ultimate (adap- tive) reasons for the restriction of reproduction to specific times of year. Females of almost all temperate-zone reptile species produce their eggs or offspring in the warmest time of the year, thereby synchronizing embryogenesis with high ambient

  6. Molecular cloning and sexually dimorphic expression of DM-domain genes in Daphnia magna

    Microsoft Academic Search

    Yasuhiko Kato; Kaoru Kobayashi; Shigeto Oda; John K. Colbourn; Norihisa Tatarazako; Hajime Watanabe; Taisen Iguchi

    2008-01-01

    Daphnia magna is known to switch between sexual and asexual reproduction depending on the environment. It reproduces asexually when in an optimal environment for food, photoperiod, and population density. Once the environment declines, it changes reproductive strategy from asexual to sexual reproduction. However, the molecular bases of environmental sex determination are largely unknown. To understand the molecular mechanisms of environmental

  7. Discovery of a Sexual Cycle in Aspergillus lentulus, a Close Relative of A. fumigatus

    PubMed Central

    Swilaiman, Sameira S.; O'Gorman, Céline M.; Balajee, S. Arunmozhi

    2013-01-01

    Aspergillus lentulus was described in 2005 as a new species within the A. fumigatus sensu lato complex. It is an opportunistic human pathogen causing invasive aspergillosis with high mortality rates, and it has been isolated from clinical and environmental sources. The species is morphologically nearly identical to A. fumigatus sensu stricto, and this similarity has resulted in their frequent misidentification. Comparative studies show that A. lentulus has some distinguishing growth features and decreased in vitro susceptibility to several antifungal agents, including amphotericin B and caspofungin. Similar to the once-presumed-asexual A. fumigatus, it has only been known to reproduce mitotically. However, we now show that A. lentulus has a heterothallic sexual breeding system. A PCR-based mating-type diagnostic detected isolates of either the MAT1-1 or MAT1-2 genotype, and examination of 26 worldwide clinical and environmental isolates revealed similar ratios of the two mating types (38% versus 62%, respectively). MAT1-1 and MAT1-2 idiomorph regions were analyzed, revealing the presence of characteristic alpha and high-mobility-group (HMG) domain genes, together with other more unusual features such as a MAT1-2-4 gene. We then demonstrated that A. lentulus possesses a functional sexual cycle with mature cleistothecia, containing heat-resistant ascospores, being produced after 3 weeks of incubation. Recombination was confirmed using molecular markers. However, isolates of A. lentulus failed to cross with highly fertile strains of A. fumigatus, demonstrating reproductive isolation between these sibling species. The discovery of the A. lentulus sexual stage has significant implications for the management of drug resistance and control of invasive aspergillosis associated with this emerging fungal pathogen. PMID:23650087

  8. Reproductive strategy, sexual development and attraction to facial characteristics

    Microsoft Academic Search

    R. Elisabeth Cornwell; Miriam J. Law Smith; Lynda G. Boothroyd; Fhionna R. Moore; Hasker P. Davis; Michael Stirrat; Bernard Tiddeman; David I. Perrett

    2006-01-01

    Sexual reproduction strategies vary both between and within species in the level of investment in offspring. Life-history theories suggest that the rate of sexual maturation is critically linked to reproductive strategy, with high investment being associated with few offspring and delayed maturation. For humans, age of puberty and age of first sex are two developmental milestones that have been associated

  9. Sexual selection and reproductive careers in mandrills ( Mandrillus sphinx )

    Microsoft Academic Search

    Joanna M. Setchell; Marie Charpentier; E. Jean Wickings

    2005-01-01

    In sexually dimorphic, polygynous species, where males provide little parental care and competition between males for access to fertile females is high, sexual selection theory predicts sex differences in age-specific reproductive output and mortality profiles, and greater variance in lifetime reproductive success in males than in females. We examined age-specific reproductive output, mortality patterns and the extent and causes of

  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. Mediators of sexual revictimization risk in adult sexual assault victims.

    PubMed

    Ullman, Sarah E; Vasquez, Amanda L

    2015-04-01

    This study examined sexual risk behaviors and sexual refusal assertiveness in relationship to child sexual abuse, emotion dysregulation, and adult sexual revictimization. Path analyses of 1,094 survivors who had sex in the past year were done to examine sexual risk behavior and sexual refusal assertiveness mediational pathways by which child sexual abuse severity and emotion dysregulation may affect revictimization over one year in adult female sexual assault survivors. Exchanging sex for money and sexual refusal assertiveness were significantly associated with emotion dysregulation, whereas exchanging sex for money, and not sexual refusal assertiveness, was only significantly related to child sexual abuse severity. Both exchanging sex for money and sex refusal assertiveness mediated the relationship between emotion dysregulation and adult sexual revictimization. Exchanging sex for money mediated the child sexual abuse severity-revictimization relationship. These findings demonstrate the importance of considering both risky and protective sexual behaviors in research and prevention programming that address sexual revictimization in women. PMID:25942287

  12. PsMPK7, a stress-associated mitogen-activated protein kinase (MAPK) in Phytophthora sojae, is required for stress tolerance, reactive oxygenated species detoxification, cyst germination, sexual reproduction and infection of soybean.

    PubMed

    Gao, Jian; Cao, Mingna; Ye, Wenwu; Li, Haiyang; Kong, Liang; Zheng, Xiaobo; Wang, Yuanchao

    2015-01-01

    The sensing of stress signals and their transduction into appropriate responses are crucial for the adaptation, survival and infection of phytopathogenic fungi and oomycetes. Amongst evolutionarily conserved pathways, mitogen-activated protein kinase (MAPK) cascades function as key signal transducers that use phosphorylation to convey information. In this study, we identified a gene, designated PsMPK7, one of 14 predicted genes encoding MAPKs in Phytophthora sojae. PsMPK7 was highly transcribed in each tested stage, but was up-regulated in the zoospore, cyst and cyst germination stages. Silencing of PsMPK7 affected the growth of germinated cysts, oospore production and the pathogenicity of soybean. PsMPK7 transcription was induced by stresses from sorbitol, NaCl and hydrogen peroxide. Transformants in which PsMPK7 expression was silenced (PsMPK7-silenced) were significantly more sensitive to osmotic and oxidative stress. Aniline blue and diaminobenzidine staining revealed that the silenced lines did not suppress the host reactive oxygen species (ROS) burst, indicating that either the inoculated plants activated stronger defence responses to the transformants and/or the PsMPK7-silenced transformants failed to overcome plant defences. In addition, extracellular secretion of laccase decreased in the silenced lines. Overall, our results indicate that the PsMPK7 gene encodes a stress-associated MAPK in P.?sojae that is important not only for responses to various stresses, but also for ROS detoxification, cyst germination, sexual oospore production and infection of soybean. PMID:24889742

  13. ON THE LIMITS OF CULTURE: WHY BIOLOGY IS IMPORTANT IN THE STUDY OF VICTORIAN SEXUALITY

    Microsoft Academic Search

    ROBERT BURNS

    Much recent scholarship in Victorian studies has viewed sexuality as historically contingent and constructed primarily within the realm of discourse or social organization. In contrast, the following study details species-typical and universal aspects of human sexuality that must be adequately theorized if an accurate model of the ideological forces impacting Victorian sexuality is to be fashioned. After a short survey

  14. Responding to Sexual Assault

    E-print Network

    Ravikumar, B.

    University will not tolerate sexual assault in any form, including acquaintance rape. Where there is probable assault, we think of rape. However, rape is not the only type of sexual assault. These words can be used

  15. Rape (sexual assault) - overview

    MedlinePLUS

    Sex and rape; Date rape; Sexual assault ... Most estimates say that 80 - 90% of rapes are not reported to police. Current trends project that 1 in 3 American women will be sexually assaulted at some point during their ...

  16. 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 ...

  17. Child Sexual Abuse

    MedlinePLUS

    ... noncontact abuse, such as exposure, voyeurism, and child pornography. Sexually abused children may also develop the following: ... in drawings, games, fantasies unusual aggressiveness, or suicidal behavior Child sexual abusers can make the child very ...

  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. Reproducibility responsibilities in the HPC arena

    SciTech Connect

    Fahey, Mark R [ORNL; McLay, Robert [Texas Advanced Computing Center

    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.

  20. Simultaneous hermaphrodites reproducing in pairs self-fertilize some of their eggs: an experimental test of predictions of mixed-mating and Hermaphrodite's Dilemma theory.

    PubMed

    Lüscher, A; Milinski, M

    2003-09-01

    Theory predicts (1) that mixed-mating systems (i.e. reproduction through both selfing and outcrossing) should usually not evolve and (2) that reproducing simultaneous hermaphrodites should be in a conflict over the preferred sexual role (The Hermaphrodite's Dilemma). In an in vitro system with the endoparasitic cestode Schistocephalus solidus, a simultaneous hermaphrodite, we tested predictions of both the mixed-mating and the Hermaphrodite's Dilemma theory. Using microsatellite markers, we measured the proportion of selfed offspring and the total reproductive output of each worm within pairs varying in mean weight and weight difference. Worms produced more outbred offspring not only with increasing total weight of the pair, but also with decreasing weight difference between the two paired worms. These results suggest: (1) that this parasite species reproduces by mixed-mating, which may be maintained by stochastic density fluctuations in the definitive host and hence unpredictability of self reproduction and (2) reproductive conflict may prevent worm pairs from achieving an optimal intermediate selfing rate. PMID:14635918

  1. Schooling & Sexualities: Teaching for a Positive Sexuality.

    ERIC Educational Resources Information Center

    Laskey, Louise, Ed.; Beavis, Catherine, Ed.

    This collection of papers contains a Foreword by Jane Kenway, an Introduction by Louise Laskey and Catherine Beavis, and four sections. Section 1, Schools and the Social Construction of Sexuality, contains 3 chapters: (1) Power and Partnership? Challenging the Sexual Construction of Schooling (D. Denborough); (2) Where Do You Draw the Line?…

  2. ORIGINAL PAPER Sexual Self-Schemas, Sexual Dysfunction, and the Sexual Responses

    E-print Network

    Meston, Cindy

    ORIGINAL PAPER Sexual Self-Schemas, Sexual Dysfunction, and the Sexual Responses of Women with a History of Childhood Sexual Abuse Alessandra H. Rellini · Cindy M. Meston Received: 30 June 2009 / Revised to the mediating effects of sexual self-schemas on the sexual difficulties of women with a history of childhood

  3. Sexual Revictimization: The Role of Sexual Self-Esteem and Dysfunctional Sexual Behaviors

    Microsoft Academic Search

    Lisa K. Van Bruggen; Marsha G. Runtz; Helena Kadlec

    2006-01-01

    Disproportionately high rates of sexual revictimization have been noted among former victims of child sexual abuse (CSA), yet researchers have yet to determine the source of this apparent vulnerability to reexperience sexual violence. This study explores this issue by examining sexual self-esteem, sexual concerns, and sexual behaviors among 402 university women. Compared to women without a history of CSA (n

  4. Child Sexual Abuse

    MedlinePLUS

    Sexual abuse is one form of child abuse. It includes a wide range of actions between a child and an adult or older child. ... child for pornography is also sexual abuse. Most sexual abusers know the ... If you think a child may have been abused, it's important to report it.

  5. Sexual Harassment in Education.

    ERIC Educational Resources Information Center

    Campbell, D'Ann

    1986-01-01

    In a recent BEST (Bureau of Evaluative Studies and Testing, Indiana University, Bloomington) survey, 10 percent of Indiana University women who responded had experienced some form of sexual harassment. Sexual harassment in education is any attention of a sexual nature from an instructor or professor which makes a student uncomfortable in class or…

  6. Reproducible network benchmarks with coNCEPTUAL

    SciTech Connect

    Pakin, S. D. (Scott 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.

  7. Female sexual arousal in amphibians.

    PubMed

    Wilczynski, Walter; Lynch, Kathleen S

    2011-05-01

    Rather than being a static, species specific trait, reproductive behavior in female amphibians is variable within an individual during the breeding season when females are capable of reproductive activity. Changes in receptivity coincide with changes in circulating estrogen. Estrogen is highest at the point when females are ready to choose a male and lay eggs. At this time female receptivity (her probability of responding to a male vocal signal) is highest and her selectivity among conspecific calls (measured by her probability of responding to a degraded or otherwise usually unattractive male signal) is lowest. These changes occur even though females retain the ability to discriminate different acoustic characteristics of various conspecific calls. After releasing her eggs, female amphibians quickly become less receptive and more choosy in terms of their responses to male sexual advertisement signals. Male vocal signals stimulate both behavior and estrogen changes in amphibian females making mating more probable. The changes in female reproductive behavior are the same as those generally accepted as indicative of a change in female sexual arousal leading to copulation. They are situationally triggered, gated by interactions with males, and decline with the consummation of sexual reproduction with a chosen male. The changes can be triggered by either internal physiological state or by the presence of stimuli presented by males, and the same stimuli change both behavior and physiological (endocrine) state in such a way as to make acceptance of a male more likely. Thus amphibian females demonstrate many of the same general characteristics of changing female sexual state that in mammals indicate sexual arousal. PMID:20816968

  8. Reproducibility in patient-specific IMRT QA.

    PubMed

    McKenzie, Elizabeth M; Balter, Peter A; Stingo, Francesco C; Jones, Jimmy; Followill, David S; Kry, Stephen F

    2014-01-01

    The purpose of this study was to determine the reproducibility of patient-specific, intensity-modulated radiation therapy (IMRT) quality assurance (QA) results in a clinical setting. Six clinical patient plans were delivered to a variety of devices and analyses, including 1) radiographic film; 2) ion chamber; 3) 2D diode array delivered and analyzed in three different configurations (AP delivery with field-by-field analysis, AP delivery with composite analysis, and planned gantry angle delivery); 4) helical diode array; and 5) in-house-designed multiple ion chamber phantom. The six clinical plans were selected from a range of treatment sites and were of various levels of complexity. Of note, three of the plans had failed at least preliminary evaluation with our in-house IMRT QA; the other three plans had passed QA. These plans were delivered three times sequentially without changing the setup, and then delivered two more times after breaking down and rebuilding the setup between each. This allowed for an investigation of reproducibility (in terms of dose, dose difference or percent of pixels passing gamma) of both the delivery and the physical setup. This study showed that the variability introduced from the setup was generally higher than the variability from redelivering the plan. Radiographic film showed the poorest reproducibility of the dosimeters investigated. In conclusion, the various IMRT QA systems demonstrated varying abilities to reproduce QA results consistently. All dosimetric devices demonstrated a reproducibility (coefficient of variation) of less than 4% in their QA results for all plans, with an average reproducibility of less than 2%. This work provides some quantification for the variability that may be seen for IMRT QA dosimeters. PMID:24892350

  9. Postcopulatory Sexual Selection and the Evolution of Male Pregnancy in the Gulf Pipefish 

    E-print Network

    Paczolt, Kimberly

    2012-07-16

    . As in precopulatory sexual selection, postcopulatory sexual selection can occur as the result of interactions within a sex, usually as sperm competition (Parker 1970), or between sexes, usually as cryptic female choice (Eberhard 1996). Sperm competition includes... to offspring from a preferred mate (Burley 1988, Sheldon 2000). Previous studies in postcopulatory sexual selection have focused on species with traditional sex roles, where males compete for access to females. By studying postcopulatory sexual selection...

  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. Risk, individual differences, and environment: an Agent-Based Modeling approach to sexual risk-taking.

    PubMed

    Nagoski, Emily; Janssen, Erick; Lohrmann, David; Nichols, Eric

    2012-08-01

    Risky sexual behaviors, including the decision to have unprotected sex, result from interactions between individuals and their environment. The current study explored the use of Agent-Based Modeling (ABM)-a methodological approach in which computer-generated artificial societies simulate human sexual networks-to assess the influence of heterogeneity of sexual motivation on the risk of contracting HIV. The models successfully simulated some characteristics of human sexual systems, such as the relationship between individual differences in sexual motivation (sexual excitation and inhibition) and sexual risk, but failed to reproduce the scale-free distribution of number of partners observed in the real world. ABM has the potential to inform intervention strategies that target the interaction between an individual and his or her social environment. PMID:22042161

  12. REPRODUCIBILITY IN INTERLABORATORY IMPACT SOUND INSULATION MEASUREMENTS

    Microsoft Academic Search

    Antonio Pedro; O. Carvalho

    This paper presents the results of an interlaborato ry comparison test concerning the impact sound insulation for a concrete slab floor to deter mine the reproducibility for the weighted normalized impact sound pressure level L'n,w and for all the involved main parameters (reverberation time and impact normalized sound pressure level, at the receiving room and for each 100 to 3150

  13. ON REPRODUCIBILITY AND TRACEABILITY OF SIMULATIONS

    E-print Network

    Paris-Sud XI, Université de

    ON REPRODUCIBILITY AND TRACEABILITY OF SIMULATIONS Olivier Dalle University of Nice Sophia the notion of traceability and its potential use in order to improve the simulation methodology. 1 a computerized representation of the system under study (called the simulation model), and to test hypotheses

  14. Multiresolution Reproducing Kernel Particle Methods in Acoustics

    E-print Network

    Liu, Wing Kam

    In the analysis of complex phenomena of acoustic systems, the computational model­ ing requires special attention window function which translates and dilates in space and time to cover the entire domain of interestMultiresolution Reproducing Kernel Particle Methods in Acoustics R. A. Uras Reactor Engineering

  15. 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.

  16. Reproducibility, Controllability, and Optimization of Lenr Experiments

    Microsoft Academic Search

    David J. Nagel

    2006-01-01

    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.

  17. Reproducing color images using custom inks

    Microsoft Academic Search

    Eric J. Stollnitz; Victor Ostromoukhov; David H. Salesin

    1998-01-01

    We investigate the general problem of reproducing color images on an offset press using custom inks in any combination and number. While this problem has been explored previously for the case of two inks, there are a number of new mathematical and algorithmic chal- lenges that arise as the number of inks increases. These challenges include more complex gamut mapping

  18. Reproducibility of twitch and sniff transdiaphragmatic pressures

    Microsoft Academic Search

    Y. M Luo; N Hart; N Mustfa; W. D. C Man; G. F Rafferty; M. I Polkey; J Moxham

    2002-01-01

    Twitch transdiaphragmatic pressure (Tw Pdi) measured with magnetic stimulation of the phrenic nerve is used to follow up patients and to assess the effect of clinical treatments on diaphragm function. However the reproducibility of Tw Pdi on different occasions has been little studied. We investigated 32 normal subjects, measuring Tw Pdi elicited by bilateral magnetic stimulation of the phrenic nerves

  19. Europe Today: An Atlas of Reproducible Pages.

    ERIC Educational Resources Information Center

    World Eagle, Inc., Wellesley, MA.

    Illustrative black and white maps, tables, and graphs designed for clear reproducibility depict Europe's size, population, resources, commodities, trade, cities, schooling, jobs, energy, industry, demographic statistics, food, and agriculture. Also included are 33 United States Department of State individual country maps. This volume is intended…

  20. Human sexual response.

    PubMed

    Basson, Rosemary

    2015-01-01

    The human sexual response to sexually arousing stimuli is a motivational incentive-based cycle comprising subjective experience and physiologic changes. Clinical and empirical data support a circular model of overlapping phases of variable order. Brain imaging data of sexual arousal identify areas of cerebral activation and inhibition reflecting a complex network of cognitive, motivational, emotional, and autonomic components. Psychologic and biologic factors influence the brain's appraisal and processing of sexual stimuli to allow or disallow subsequent arousal. The sexual and non-sexual outcomes influence motivation to future sexual intimacy. Variability is marked both between individuals and within a person's sexual life, influenced by multiple factors, including stage of life cycle, mental health, and relationship happiness. Neurologic disease can interrupt the cycle at many points: by limiting motivation, reducing ability to attend to and feel sexual stimuli, and accomplishing the movements needed to stimulate and experience intercourse. Impairments to genital congestion, penile erection, and orgasm may also occur. Disease-associated changes to the interpersonal relationship and self-image plus frequently comorbid depression will tend to lessen motivation and temper the brain's appraisal of sexual stimuli, so precluding arousal. Therapy begins by explaining the sexual response cycle, clarifying the points of interruption in the patient's own cycle so as to guide treatment. PMID:26003236

  1. 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

  2. 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

  3. RESPONSE TO SEXUAL DISCRIMINATION/HARASSMENT Sexual Harassment

    E-print Network

    Mayfield, John

    , written or electronic. Determination as to whether the alleged conduct constitutes sexual harassmentRESPONSE TO SEXUAL DISCRIMINATION/HARASSMENT Sexual Harassment Sexual harassment is a form of discrimination, as defined in the university Discrimination and Harassment policy. Sexual harassment can include

  4. Brandeis University prohibits all forms of sexual misconduct (including sexual

    E-print Network

    Snider, Barry B.

    Brandeis University prohibits all forms of sexual misconduct (including sexual assault, sexual of the resources below for help. A RESOURCE GUIDE FOR SExUAl ASSAUlt SURVIVORS Updated May 2014 Office Of c AND ASSISTANCE Sexual assault Services and prevention Specialist Sheila McMahon 781-736-3626 smcmahon

  5. A New Paradigm for Understanding Women's Sexuality and Sexual Orientation

    Microsoft Academic Search

    Letitia Anne Peplau; Linda D. Garnets

    2000-01-01

    Major scientific findings about women's sexuality and sexual orientation are reviewed. Sexual orientation is unrelated to mental health. There is no inherent association between gender conformity and women's sexual orientation; mascu- linity and femininity are linked to sexual orientation in some social contexts but not in others. Research has so far failed to identify major biological or childhood ante- cedents

  6. Late Adolescent Girls' Sexual Experiences and Sexual Satisfaction

    ERIC Educational Resources Information Center

    Impett, Emily A.; Tolman, Deborah L.

    2006-01-01

    This study presented and tested a model of sexual satisfaction for late adolescent girls. In this model, sexual self-concept and approach sexual motives were tested as predictors of adolescent girls' sexual satisfaction with their most recent experience of sexual intercourse. A total of 116 girls in 12th grade (ages 16-19) completed measures of…

  7. Sexual At-Risk Behaviors of Sexually Abused Adolescent Girls

    ERIC Educational Resources Information Center

    Cinq-Mars, Caroline; Wright, John; Cyr, Mireille; McDuff, Pierre

    2003-01-01

    The present study investigated sexual at-risk behaviors of sexually abused adolescent girls. Variables of interest were presence of consensual sexual activity, age at first consensual intercourse, number of sexual partners, condom use, and pregnancies. Participants were 125 sexually abused adolescent girls aged 12 to 17 years. Results showed that…

  8. 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

  9. 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

  10. Instability of the sexual continuum

    PubMed Central

    Noest, A. J.

    1997-01-01

    Maynard Smith and Szathmary have posed the problem of demonstrating the conjectured instability of a continuum of sexual types with finite interbreeding. Here, I propose a model in which one can analyse exactly when and how the existence of the instability can depend on an Allee effect, and how the growth rate and typical scale of the unstable perturbations depend on the strength and range of competition, mating preference, fecundity and offspring variance due to Mendelian segregation and mutation. Instabilities of various kinds are shown to occur in the majority of parameter regimes. In short, the continuum often breaks up into incipient species.

  11. The Evolution of Sexual Pleasure

    Microsoft Academic Search

    Felicia De la Garza-Mercer

    2007-01-01

    Sexual pleasure is an innate component of human sexuality. Although disdained throughout history by religious groups and variably explained by theories, philosophers, and societies, sexual pleasure permeates human experience. Traditional evolutionists explain this preoccupation via the development of sexual mating strategies and the human desire to propagate one's genes; however, here I will argue that the saturation of sexual pleasure

  12. Nonvolitional Sex and Sexual Health

    Microsoft Academic Search

    Debra Kalmuss

    2004-01-01

    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

  13. An International Ki67 Reproducibility Study

    PubMed Central

    2013-01-01

    Background In breast cancer, immunohistochemical assessment of proliferation using the marker Ki67 has potential use in both research and clinical management. However, lack of consistency across laboratories has limited Ki67’s value. A working group was assembled to devise a strategy to harmonize Ki67 analysis and increase scoring concordance. Toward that goal, we conducted a Ki67 reproducibility study. Methods Eight laboratories received 100 breast cancer cases arranged into 1-mm core tissue microarrays—one set stained by the participating laboratory and one set stained by the central laboratory, both using antibody MIB-1. Each laboratory scored Ki67 as percentage of positively stained invasive tumor cells using its own method. Six laboratories repeated scoring of 50 locally stained cases on 3 different days. Sources of variation were analyzed using random effects models with log2-transformed measurements. Reproducibility was quantified by intraclass correlation coefficient (ICC), and the approximate two-sided 95% confidence intervals (CIs) for the true intraclass correlation coefficients in these experiments were provided. Results Intralaboratory reproducibility was high (ICC = 0.94; 95% CI = 0.93 to 0.97). Interlaboratory reproducibility was only moderate (central staining: ICC = 0.71, 95% CI = 0.47 to 0.78; local staining: ICC = 0.59, 95% CI = 0.37 to 0.68). Geometric mean of Ki67 values for each laboratory across the 100 cases ranged 7.1% to 23.9% with central staining and 6.1% to 30.1% with local staining. Factors contributing to interlaboratory discordance included tumor region selection, counting method, and subjective assessment of staining positivity. Formal counting methods gave more consistent results than visual estimation. Conclusions Substantial variability in Ki67 scoring was observed among some of the world’s most experienced laboratories. Ki67 values and cutoffs for clinical decision-making cannot be transferred between laboratories without standardizing scoring methodology because analytical validity is limited. PMID:24203987

  14. Sexuality: sexual activity and contraception during adolescence.

    PubMed

    Creatsas, G K

    1993-12-01

    Adolescent sexual activity is increasing. Premature sexual intercourse results in high figures of adolescent pregnancy and abortion, as well as in increased risk of sexually transmitted diseases (STDs). Lack of information on the prevention of STDs and poor hygiene in both boys and girls are also main reasons for increased morbidity because of STDs during adolescence. Contraceptive behaviour during adolescence varies between countries and communities. It seems, however, that the condom and oral contraceptives (OC) are popular contraceptive methods. Ineffective methods such as periodic abstinence, coitus interruptus, and withdrawal before ejaculation are in use. On the other hand, compliance of adolescents on contraception is poor. The above are additional causes for increasing rates of adolescent pregnancies. Countries providing sexual education programs in schools present lower rates of pregnancy and abortion. Adolescent pregnancy is safe if a careful follow up is accepted by the teenager. A significant number of homeless youth are homosexuals or lesbian adolescents. Most of them are at high risk for HIV infection, AIDS, and STDs. It is concluded that sexual education programs are absolutely necessary to offer adolescents the knowledge on the complications of premature sexual activity, as well as prevention of the undesired pregnancy and STDs. PMID:8286689

  15. Selection on apomictic lineages of Taraxacum at establishment in a mixed sexual-apomictic population

    Microsoft Academic Search

    De Kovel; De Jong

    2000-01-01

    apomixis; asexuality; evolution; polyploidy; selection; Taraxacum. Abstract A species' mode of reproduction, sexual or asexual, will affect its ecology and evolution. In many species, asexuality is related to polyploidy. In Taraxacum, apomicts are triploid, and sexuals are diploid. To disentangle the effects of ploidy level and reproductive mode on life-history traits, we compared established apomictic Taraxacum genotypes with newly synthesized

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

    E-print Network

    Kelley, Darcy B.

    receptivity vocally, this species offers a rare opportunity to investigate acoustic recognition of sexSignificance 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

  17. Sexual differences in coloration of Coenagrionid damselflies (Odonata): a case of intraspecific aposematism?

    Microsoft Academic Search

    Thomas N. Sherratt; Mark R. Forbes

    2001-01-01

    Sexual dimorphism is commonly explained as a consequence of selection on traits that increase male attractiveness to females, or simply allow males greater access to females. Here, we consider another explanation for sexual differences in coloration within species of the damselfly family Coenagrionidae (Odonata: Zygoptera). In many of these species, males are more brightly coloured than females and have different

  18. Sexual interest, attitudes, knowledge, and sexual history in relation to sexual behavior in the institutionalized aged

    Microsoft Academic Search

    Charles B. White

    1982-01-01

    Although the idea that sexuality is a lifelong need is gaining greater research support and greater acceptability to the general public, few consider the institutionalized aged as having sexual needs or being able to benefit from sexual intimacy. The research presented here indicates that sexual activity in the institutionalized aged is related to their attitudes and behavior to ward sexuality

  19. ORIGINAL PAPER Sexual Self-Schemas, Sexual Dysfunction, and the Sexual Responses

    E-print Network

    Meston, Cindy

    ORIGINAL PAPER Sexual Self-Schemas, Sexual Dysfunction, and the Sexual Responses of Women with a History of Childhood Sexual Abuse Alessandra H. Rellini · Cindy M. Meston Received: 30 June 2009 / Revised access at Springerlink.com Abstract Accumulating evidence points to the mediating effects of sexual self

  20. Parental Non-verbal Sexual Communication: Its Relationship to Sexual Behaviour and Sexual Guilt

    Microsoft Academic Search

    Hélène Joffe; Ana ClÁUdia Franca-Koh

    2001-01-01

    The study explores the link between remembered non-verbal sexual communication in the home, current sexual behaviours and feelings of sexual guilt, among a sample of young British men and women. Non-verbal sexual communication encapsulates: openness about nudity in the home; the showing of affection between parents; signs of parental sexual activity and contraceptive use; and intimation of mother's menstruation. One

  1. 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

  2. [Sexuality and urological diseases].

    PubMed

    Droupy, Stéphane

    2014-10-01

    Patients with lower urinary tract symptoms related to benign prostatic hyperplasia (BPH) frequently suffer from sexual dysfunction (erectile dysfunction and ejaculatory dysfunction). Erectile dysfunction and premature ejaculation are two times more common in men with chronic pelvic pain/chronic prostatitis. All treatments of prostate cancer are responsible for sexual dysfunctions. Sexual disorders frequently appear during the management of infertile couples. Information and support should be offered to couples. Women with urinary incontinence also suffer frequently from coital incontinence. PMID:25201599

  3. Transsexuals' Sexual Stories

    Microsoft Academic Search

    Douglas P. Schrock; Lori L. Reid

    2006-01-01

    When viewed through a popular cultural lens, male-to-female transsexuals' sexual biographies can appear to indicate male transvestitism,\\u000a heterosexuality, or homosexuality rather than transsexuality. How do transsexuals subvert such implications and construct\\u000a transsexual identities? Drawing on K. Plummer's (1995) approach to sexual stories, we examine how nine male-to-female transsexuals\\u000a construct their sexual pasts to accomplish what sociologists call “identity work.” Interviewees

  4. Sexual Orientation Disparities in Sexually Transmitted Infections: Examining the Intersection Between Sexual Identity and Sexual Behavior

    PubMed Central

    Everett, Bethany G.

    2013-01-01

    The terms MSM (men who have sex with men) and WSW (women who have sex with women) have been used with increasing frequency in the public health literature to examine sexual orientation disparities in sexual health. These categories, however, do not allow researchers to examine potential differences in sexually transmitted infection (STI) risk by sexual orientation identity. Using data from the National Longitudinal Survey of Adolescent Health, this study investigated the relationship between self-reported STIs and both sexual orientation identity and sexual behaviors. Additionally, this study examined the mediating role of victimization and STI risk behaviors on the relationship between sexual orientation and self-reported STIs. STI risk was found to be elevated among heterosexual-WSW and bisexual women, whether they report same-sex partners or not, whereas gay-identified WSW were less likely to report an STI compared to heterosexual women with opposite sex relationships only. Among males, heterosexual-identified MSM did not have a greater likelihood of reporting an STI diagnosis; rather, STI risk was concentrated among gay and bisexual identified men who reported both male and female sexual partners. STI risk behaviors mediated the STI disparities among both males and females, and victimization partially mediated STI disparities among female participants. These results suggest that relying solely on behavior-based categories, such as MSM and WSW, may mischaracterize STI disparities by sexual orientation. PMID:22350122

  5. 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

  6. Sexual assault documentation program.

    PubMed

    Willoughby, Vickie; Heger, Astrid; Rogers, Christopher; Sathyavagiswaran, Lakshmanan

    2012-03-01

    Since 2001, the Los Angeles County Department of Coroner has collaborated with Los Angeles County-University of Southern California Medical Center Violence Intervention Program and their Sexual Assault Center. The partnership was established at the suggestion of the district attorney's office to enhance the clinical recognition of sexual assault in the medical examiner's office using the extensive experience of experts in the field of sexual assault. As of December 2008, over 5 dozen victims of sexual assault have been evaluated with this collaboration. The partnership relied on the expertise of 2 pediatricians who are established clinical experts in the field of sexual abuse and assault, in collaboration with the staff of the medical examiner's office. In cases of suspected sexual assault, a joint evaluation by the clinical experts and the medical examiner was made. The goal of the project was for the medical examiners to become more confident in their observations and documentation of crimes of sexual abuse. Even though they are still available upon request, consultations with the sexual assault experts have decreased as the skills of the medical examiner to evaluate sexual assault cases have increased. PMID:22442832

  7. Academic Sexual Correctness

    NSDL National Science Digital Library

    This list on the subject of academic sexual correctness(ASC-L). ASC-L was an outgrowth of CASE (Consenting Academics for Sexual Equity), founded in early 1994 by both professors and students to combat a concerted "feminist" campaign against students and professors who had become involved in an intimate(romantic) relationship. CASE dealt with only one small area of the current emphasis on sexual correctness in academia. Consequently, the need for a network that focused on all aspects of academic sexual correctness became apparent; the ASC-L was a response to that need. ASC-L encompasses all aspects of campus sexual control issues -- irrespective of their ideological origins, such as sexual consent issues, sexual discrimination issues (irrespective of the subjects of the discrimination) and attempts to regulate sexual content of speech on campus or sexual content of course materials. The principles of consent, privacy and academic freedom are the core principles which have motivated the founding of ASC-L.

  8. 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…

  9. Sexual Self-Schemas of Female Child Sexual Abuse Survivors: Relationships with Risky Sexual Behavior and Sexual Assault in Adolescence

    Microsoft Academic Search

    Ashley F. NiehausJoan; Joan Jackson; Stephanie Davies

    2010-01-01

    Childhood sexual trauma has been demonstrated to increase survivors’ risk for engaging in unrestricted sexual behaviors and\\u000a experiencing adolescent sexual assault. The current study used the sexual self-schema construct to examine cognitive representations\\u000a of sexuality that might drive these behavioral patterns. In Study 1 (N = 774), we attempted to improve the content validity of the Sexual Self Schema Scale for child

  10. Sexual Self-Schemas, Sexual Dysfunction, and the Sexual Responses of Women with a History of Childhood Sexual Abuse

    Microsoft Academic Search

    Alessandra H. RelliniCindy; Cindy M. Meston

    2011-01-01

    Accumulating evidence points to the mediating effects of sexual self-schemas on the sexual difficulties of women with a history\\u000a of childhood sexual abuse (CSA). The following study adds to the extant literature by investigating (1) sexual function and\\u000a (2) sexual satisfaction utilizing validated measures, and reporting on the relationship between sexual self-schemas and physiological\\u000a (vaginal photoplethysmography), subjective, and affective responses

  11. Sexual selection and speciation: Issues raised by Hawaiian Drosophila.

    PubMed

    Kaneshiro, K Y; Boake, C R

    1987-07-01

    The Drosophila fauna of Hawaii is extraordinarily diverse, representing about 25% of the world's described species. The most notable characteristics which differentiate the species in Hawaii are morphological and behavioral ones used in courtship and mating. These flies are excellent model species for investigating the evolution of sexually selected traits. Hypotheses regarding the associations between species formation and mating behaviour have been formulated as a result of work on this group, leading to further empirical and theoretical research. PMID:21227852

  12. Reproducibility of Genucom knee analysis system testing.

    PubMed

    Wroble, R R; Grood, E S; Noyes, F R; Schmitt, D J

    1990-01-01

    The Genucom knee analysis system was studied to determine the reproducibility of test results. In the first phase of the study we investigated the reproducibility of anterior/posterior stress tests at 30 degrees and 90 degrees of flexion and varus/valgus stress tests at 20 degrees of flexion in 10 control subjects during three seatings on 3 separate days. In the second phase we studied the effect of errors in the digitization procedure (a part of the patient installation process) on anterior/posterior translation measurements. In the third phase we studied the reproducibility of a battery of tests in patients with chronic unilateral ACL deficient knees. The test battery was repeated 8 times on each knee on 6 separate days. In Phase I, analysis of variance revealed no significant differences between tests within a single seating. The day-to-day variance of all subjects was not significant, but we found a significant interaction between day and subject which was due to significant day-to-day differences in individual subjects. We found in Phase II that changing the location of the tibial joint line digitization points in the anterior/posterior or proximal/distal direction affected anterior/posterior translation measurements. Effects were larger at 30 degrees of flexion than at 90 degrees and when both the medial and lateral points were moved. Movement of the femoral condylar points resulted in a similar pattern of effects. In Phase III, although we found significant differences between our two examiners, there were no significant intraexaminer test-to-test (within seating) effects. Additionally, while there was no significant day-to-day variance overall, we found a significant interaction between day and subject.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2403188

  13. 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.

  14. Potential role of the sexually transmitted mite Coccipolipus hippodamiae in controlling populations of the invasive ladybird Harmonia axyridis

    E-print Network

    Jiggins, Francis

    Coccipolipus hippodamiae Sexually transmitted disease Biological control a b s t r a c t The enemy releasePotential role of the sexually transmitted mite Coccipolipus hippodamiae in controlling populations of this species is the sexually transmitted mite Coccipolipus hip- podamiae (McDaniel & Morrill) (Acarina

  15. 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.

  16. Effects of feeding level and sexual maturation on carcass and fillet characteristics and indices of protein degradation in rainbow trout (Oncorhynchus mykiss)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sexual maturation in many species of fish including salmonids requires mobilization of energy and nutrient resources to support gonad growth. During sexual maturation, particularly vitellogenesis, proteins are mobilized from muscle tissue, which is evidenced by increased expression of proteolytic g...

  17. Reproducibility of two-dimensional exercise echocardiography.

    PubMed

    Oberman, A; Fan, P H; Nanda, N C; Lee, J Y; Huster, W J; Sulentic, J A; Storey, O F

    1989-10-01

    To determine the reproducibility of two-dimensional exercise echocardiography, duplicate studies were performed on the same patients a median of 14 days apart. Because measurements are operator-dependent, interobserver variability was calculated for two experienced readers who interpreted the findings independently in a blinded manner. A high degree of interobserver agreement was found in evaluation of both ejection fraction measurements and wall motion abnormalities. Readings for ejection fraction immediately after exercise taken on different days could be estimated within 4% of the values measured in the first test; similarly measured wall motion score index was within 6% of that in the first test. Ejection fractions and wall motion scores were highly correlated between tests 1 and 2. The correlation coefficients between tests 1 and 2 were 0.92 for both the pre- and postexercise ejection fractions and 0.98 for both the pre- and postexercise wall motion scores. Quantitative two-dimensional echocardiography immediately after exercise is highly reproducible, providing a valuable tool for assessing serial changes in left ventricular function. PMID:2794280

  18. Reproducibility data on SUMMiT

    NASA Astrophysics Data System (ADS)

    Limary, Siv; Stewart, Harold D.; Irwin, Lloyd W.; McBrayer, John; Sniegowski, Jeffry J.; Montague, Stephen; Smith, James H.; de Boer, Maarten P.; Jakubczak, Jerome F.

    1999-08-01

    SUMMiT at the Sandia National Laboratories' MDL is a standardized MEMS technology that allows designers to fabricate concept prototypes. This technology provides four polysilicon layers plus three sacrificial oxide layers 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 SUMMiT 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.

  19. 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.

  20. Multiresolution reproducing kernel particle methods in acoustics.

    SciTech Connect

    Uras, R. A.; Chang, C.-T.; Chen, Y.; Liu, W. K.; Reactor Engineering; Northwestern Univ.

    1997-01-01

    In the analysis of complex phenomena of acoustic systems, the computational modeling requires special attention in order to give a realistic representation of the physics. As a powerful tool, the finite element method has been widely used in the study of complex systems. In order to capture the important physical phenomena, p-finite elements and/or hp-finite elements are employed. The Reproducing Kernel Particle Methods (RKPM) are emerging as an effective alternative due to the absence of a mesh and the ability to analyze a specific frequency range. In this study, a wavelet particle method based on the multiresolution analysis encountered in signal processing has been developed. The interpolation functions consist of spline functions with a built-in window which permits translation as well as dilation. A variation in the size of the window implies a geometrical refinement and allows the filtering of the desired frequency range. An adaptivity similar to hp-finite element method is obtained through the choice of an optimal dilation parameter. The analysis of the wave equation shows the effectiveness of this approach. The frequency/wave number relationship of the continuum case can be closely simulated by using the reproducing kernel particle methods. A similar methodology is also developed for the Timoshenko beam.

  1. 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.

  2. Precision and Reproducibility in Biological Patterning

    NASA Astrophysics Data System (ADS)

    Gregor, Thomas; Wieschaus, Eric F.; Bialek, William; Tank, David W.

    2007-03-01

    During embryonic development, information about spatial location is represented by the concentration of various morphogen molecules. The reproducibility and precision of biological pattern formation thus is limited by the accuracy with which these concentration profiles can be established and ``read out'' by their target pathways. We consider four measures of precision for the Bicoid morphogen in the Drosophila embryo: The concentration differences that distinguish neighboring cells, the limits set by the random arrival of Bcd molecules at their targets (which depends on the absolute concentration), the noise in readout of Bcd by the activation of Hunchback, and the reproducibility of Bcd concentration at corresponding positions in multiple embryos. We show, through a combination of different experiments, that all of these quantities are ˜10%. This agreement among different measures of accuracy, which depend on very different molecular mechanisms, indicates that the embryo is not faced with sloppy input signals and noisy readout mechanisms; rather we have to understand how the embryo exerts precise control over absolute concentrations and responds reliably to small changes in these concentrations, down to the limits set by basic physical principles.

  3. Ambulatory blood pressure recordings. Reproducibility and unpredictability.

    PubMed

    des Combes, B J; Porchet, M; Waeber, B; Brunner, H R

    1984-01-01

    The accuracy of blood pressure readings taken by the portable semiautomatic blood pressure recorder Remler M 2000 was investigated in 101 unselected, untreated volunteers. On the average, pressures recorded during usual daily activities were lower by approximately 10 mm Hg than pressures measured in the office. However, individual ambulatory pressures could not be predicted from office readings, and the difference varied among the volunteers from +14 to -43 mm Hg. The reproducibility of office and ambulatory pressures was investigated in 84 subjects. There was a highly significant correlation between pressure levels determined at a 3- to 4-month interval with both the conventional auscultatory method in the office and the Remler ambulatory recorder. These data demonstrate that the Remler M 2000 ambulatory blood pressure recorder, when used properly, provides reproducible blood pressure profiles during customary daily activities. The ambulatory pressure recorder seems particularly useful for a baseline evaluation of the usual daily blood pressure, which in the individual subject differs in a highly unpredictable manner from the blood pressure measured at the physician's office. PMID:6735450

  4. ‘Imported’ Sexually Transmitted Diseases

    PubMed Central

    Romanowski, Barbara

    1990-01-01

    A sexual history should be routinely obtained from all travellers. Those whose symptoms indicate a sexually transmitted disease may need to be investigated for unusual infections. Resistant strains of gonorrhea are becoming a major concern. Chancroid should be considered in the differential diagnosis of genital ulcer disease. The possiblility of human immunodeficiency virus infection should be discussed with all these patients. PMID:21233914

  5. What is clinical sexuality?

    PubMed

    Levine, S B

    1995-03-01

    A collage of eight overlapping themes for the definition of sexuality is presented prior to undertaking a historical overview of the rapid development of the field that began in 1970 as "sex therapy." The limitations of theory, behavioral science, and the art of medicine as they apply to helping people with their sexual concerns are highlighted. PMID:7761299

  6. Aging and sexuality.

    PubMed Central

    Meston, C M

    1997-01-01

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

  7. Sexual Minorities Seeking Services

    Microsoft Academic Search

    Tracey L. Rogers; Kristen Emanuel; Judith Bradford

    2002-01-01

    Understanding the mental health needs of lesbian and bisexual (sexual minority) women is an integral part of designing and providing appropriate mental health services and treatment for them. In an effort to understand the mental health needs of sexual minority women who seek community treatment, a chart review was conducted of the 223 lesbian and bisexual women who presented for

  8. [Sexuality in the elderly].

    PubMed

    Wilk, Bartosz

    2015-03-01

    Sustaining and strengthening the ability of the elderly to continue their sexual needs can be realized as part of improving their quality of life, health and well-being. There is no age at which ends the expression of sexuality and intimacy. Through education, quality of life and advances in medicine, the average life expectancy is still increasing. Sexual activity of older people society usually describe using pejorative terms as an inappropriate, bizarre or obscene, but these labels are different than reality. Hormonal changes and other physiological changes associated with aging affect sexual interest. Erectile dysfunction is a problem in men increasing with age. There is no evidence that premature ejaculation is more common in older age. Cross-sectional studies showed no difference in sexual dysfunction between older and younger women. Age is not a barrier to sexually transmitted diseases. The most common pathogenetic factors for male erectile dysfunction are vascular diseases. In women, the most important symptoms of sexual dysfunction are lack of emotional wellbeing and a sense of intimacy during sexual intercourse. PMID:25815611

  9. Disclosing Sexual Victimization

    ERIC Educational Resources Information Center

    Ciarlante, Mitru

    2007-01-01

    Exploring the process of disclosure for youth who have been sexually victimized, this article provides strategies for creating an environment where sexual violence is not accepted and where youth feel safe disclosing. It also provides strategies for working with youth who haven't yet disclosed. (Contains 1 footnote.)

  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. Psychopathy and sexual sadism.

    PubMed

    Mokros, Andreas; Osterheider, Michael; Hucker, Stephen J; Nitschke, Joachim

    2011-06-01

    Psychopathic personality disorder and sexual sadism share several common characteristics, such as emotional detachment from the suffering of others or the preparedness to inflict pain or injuries. Based on a sample of 100 male forensic patients (all of them sex offenders, half of them sadistic), the concept of psychopathy and sexual sadism as a unified construct was tested empirically. Pooling indicator variables for psychopathic and sexually sadistic disorders showed that a two-factorial solution yielded a better fit than a single-factor model. The two factors identified psychopathy and sexual sadism as separate latent variables. More specifically, the data were compatible with a path model in which affective deficits and behavioral disinhibition of the psychopathy domain are precursors to sexually sadistic conduct. PMID:20393872

  12. Sexual Desire Disorders

    PubMed Central

    Montgomery, Keith A.

    2008-01-01

    Hypoactive sexual desire disorder (HSDD) and sexual aversion disorder (SAD) are an under-diagnosed group of disorders that affect men and women. Despite their prevalence, these two disorders are often not addressed by healthcare providers and patients due their private and awkward nature. As physicians, we need to move beyond our own unease in order to adequately address our patients’ sexual problems and implement appropriate treatment. Using the Sexual Response Cycle as the model of the physiological changes of humans during sexual stimulation and the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition this article will review the current literature on the desire disorders focusing on prevalence, etiology, and treatment. PMID:19727285

  13. Televised Sexual Content and Parental Mediation: Influences on Adolescent Sexuality

    Microsoft Academic Search

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

    2009-01-01

    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

  14. Textbook Sexual Inadequacy? A Review of Sexuality Texts.

    ERIC Educational Resources Information Center

    Goettsch, Stephen L.

    1987-01-01

    Reviews eight current human sexuality textbooks for both their general organization and substantive content. Addresses specifically the content areas of sexual response cycle; sexual disfunction; acquaintance rape; AIDS and sexually transmitted diseases; extramarital sex; abortion; homosexuality; and pornography. Identifies as a recurring fault…

  15. Sexual dimorphism and age of Mediterranean salamanders.

    PubMed

    Reinhard, Sandy; Renner, Sandra; Kupfer, Alexander

    2015-02-01

    We analysed sexual size dimorphism (SSD) for two Mediterranean species of the "true" salamander clade possessing distinct life histories (Salamandra algira and Mertensiella caucasica) and equilibrated the morphometric approach to individual age by using skeletochronology. For species that have a short breeding season and live at high altitudes, such as Mediterranean amphibians, the fecundity advantage hypothesis predicts female-biased SSD to maximise reproductive success. Our results showed no SSD in either species; however, morphometric data indicated a male-biased dimorphism in limb (arm and leg) dimensions in both species when compared to body size. Limb dimorphisms are likely related to the particular mating system, which involves an amplexus during spermatophore transfer. Arm length appeared sexually dimorphic during ontogeny both in viviparous S. algira and oviparous M. caucasica. A review on SSD indicated monomorphy of body size as a common lineage-specific pattern among the "true" salamander clade, but also the common presence of other traits such as sexually dimorphic limb proportions. PMID:25497699

  16. 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

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

    PubMed

    Hines, Melissa

    2011-04-01

    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

  18. 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

  19. Post-copulatory sexual selection and sexual conflict in the evolution of male pregnancy.

    PubMed

    Paczolt, Kimberly A; Jones, Adam G

    2010-03-18

    Male pregnancy in seahorses, pipefishes and sea dragons (family Syngnathidae) represents a striking reproductive adaptation that has shaped the evolution of behaviour and morphology in this group of fishes. In many syngnathid species, males brood their offspring in a specialized pouch, which presumably evolved to facilitate male parental care. However, an unexplored possibility is that brood pouch evolution was partly shaped by parent-offspring or sexual conflict, processes that would result in trade-offs between current and future pregnancies. Here we report a controlled breeding experiment using the sexually dimorphic Gulf pipefish, Syngnathus scovelli, to test for post-copulatory sexual selection within broods and for trade-offs between successive male pregnancies as functions of female attractiveness. Offspring survivorship within a pregnancy was affected by the size of a male's mate, the number of eggs transferred and the male's sexual responsiveness. Significantly, we also found that embryo survivorship in a current pregnancy was negatively related to survivorship in the prior pregnancy, clearly demonstrating fitness trade-offs between broods. Overall, our data indicate that post-copulatory sexual selection and sexual conflict occur in Gulf pipefishes. The conflict seems to be mediated by a strategy of cryptic choice in which males increase rates of offspring abortion in pregnancies from unattractive mothers to retain resources for future reproductive opportunities. Hence, the male brood pouch of syngnathid fishes, which nurtures offspring, also seems to have an important role as an arbiter of conflict between the sexes. PMID:20237568

  20. Sexual selection, germline mutation rate and sperm competition

    PubMed Central

    Møller, AP; Cuervo, JJ

    2003-01-01

    Background An important component of sexual selection arises because females obtain viability benefits for their offspring from their mate choice. Females choosing extra-pair fertilization generally favor males with exaggerated secondary sexual characters, and extra-pair paternity increases the variance in male reproductive success. Furthermore, females are assumed to benefit from 'good genes' from extra-pair sires. How additive genetic variance in such viability genes is maintained despite strong directional selection remains an evolutionary enigma. We propose that sexual selection is associated with elevated mutation rates, changing the balance between mutation and selection, thereby increasing variance in fitness and hence the benefits to be obtained from good genes sexual selection. Two hypotheses may account for such elevated mutation: (1) Increased sperm production associated with sperm competition may increase mutation rate. (2) Mutator alleles increase mutation rates that are revealed by the expression of condition-dependent secondary sexual characters used by choosy females during their mate choice. M Petrie has independently developed the idea that mutator alleles may account for the maintenance of genetic variation in viability despite strong directional selection. Results A comparative study of birds revealed a positive correlation between mutation rate at minisatellite loci and extra-pair paternity, but not between mutation rate and relative testes mass which is a measure of relative sperm production. Minisatellite mutation rates were not related to longevity, suggesting a meiotic rather than a mitotic origin of mutations. Conclusion We found evidence of increased mutation rate in species with more intense sexual selection. Increased mutation was not associated with increased sperm production, and we suggest that species with intense sexual selection may maintain elevated mutation rates because sexual selection continuously benefits viability alleles expressed in condition-dependent characters. Sexual selection may increase mutational input, which in turn feeds back on sexual selection because of increased variance in viability traits. PMID:12702218

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

    PubMed Central

    Krüger, O; Davies, N.B; Sorenson, M.D

    2007-01-01

    Sexual dimorphism is ubiquitous in animals and can result from selection pressure on one or both sexes. Sexual selection has become the predominant explanation for the evolution of sexual dimorphism, with strong selection on size-related mating success in males being the most common situation. 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 in intense selection. Here, we show that size and plumage differences between the sexes in parasitic cuckoos are more likely the result of coevolution than sexual selection. While both sexes changed in size as brood parasitism evolved, we find no evidence for selection on males to become larger. Rather, our analysis indicates stronger selection on parasitic females to become smaller, resulting in a shift from dimorphism with larger females in cuckoos with parental care to dimorphism with larger males in parasitic species. In addition, the evolution of brood parasitism was associated with more cryptic plumage in both sexes, but especially in females, a result that contrasts with the strong plumage dimorphism seen in some other parasitic birds. Examination of the three independent origins of brood parasitism suggests that different parasitic cuckoo lineages followed divergent evolutionary pathways to successful brood parasitism. These results argue for the powerful role of parasite–host coevolution in shaping cuckoo life histories in general and sexual dimorphism in particular. PMID:17439849

  2. Sexual sadism and sadistic personality disorder in sexual homicide.

    PubMed

    Hill, Andreas; Habermann, Niels; Berner, Wolfgang; Briken, Peer

    2006-12-01

    Controversies exist about the diagnostic validity of sexual sadism and its relation to sadistic personality disorder in sex offenders. The aim of this study was to investigate which diagnostic, developmental, and criminal characteristics differentiate sexual sadistic from non-sadistic sexual homicide perpetrators. Psychiatric court reports on 166 men who had committed a sexual homicide were evaluated regarding psychiatric, sexual and criminal history. Sixty-one offenders (36.7%) with sexual sadism (SeSd) were compared with 105 (63.3%) offenders without this diagnosis (NSeSd). Besides the sexual sadistic symptoms, there were seven factors that discriminated best between the two groups (sexual masochism, sadistic personality disorder, isolation in childhood, multiple sexual homicide, previous rape, previous tendencies for similar behavior, and long duration of the homicidal act). Sexual sadism is connected with circumscribed other characteristics and has to be considered in risk assessment and treatment of sex offenders. PMID:17192143

  3. Sexual positions and sexual satisfaction of pregnant women.

    PubMed

    Lee, Jian Tao; Lin, Chao Ling; Wan, Gwo Hwa; Liang, Ching Chung

    2010-01-01

    The purpose of this study was to investigate the sexual positions and sexual satisfaction of women during pregnancy. The authors sampled pregnant women (N = 215) from outpatients registered at the antepartum clinic of a medical center in northern Taiwan. The authors gathered data on recent sexual satisfaction, general sexual satisfaction, and sexual position using a self-report, structured questionnaire. The results showed that coital frequency decreased from the first to third trimester (p < .05). The most common sexual position for pregnant women (67.6%) was man on top, face-to-face. Sexual position did not change significantly by trimester. More women with more sexual satisfaction than women with poor sexual satisfaction tended to adopt the woman-on-top, face-to-face, and abdominal-supportive sexual positions. PMID:20924936

  4. Sexual at-risk behaviors of sexually abused adolescent girls.

    PubMed

    Cinq-Mars, Caroline; Wright, John; Cyr, Mireille; McDuff, Pierre

    2003-01-01

    The present study investigated sexual at-risk behaviors of sexually abused adolescent girls. Variables of interest were presence of consensual sexual activity, age at first consensual intercourse, number of sexual partners, condom use, and pregnancies. Participants were 125 sexually abused adolescent girls aged 12 to 17 years. Results showed that severity of sexual abuse (e.g., penetration, multiple perpetrators, physical coercion, multiple incidents of abuse) was related to a greater number of sexual at-risk behaviors. For instance, adolescents with a history of sexual abuse involving penetration were 13 times as likely to have been pregnant. Although family characteristics were significantly associated with being sexually active, their effect proved non-significant in the final hierarchical regression. Regression analyses clearly showed that the likelihood of engaging in sexual at-risk behaviors increased as a function of the number of severity factors. PMID:15105081

  5. Reproducing the kinematics of damped Lyman ? systems

    NASA Astrophysics Data System (ADS)

    Bird, Simeon; Haehnelt, Martin; Neeleman, Marcel; Genel, Shy; Vogelsberger, Mark; Hernquist, Lars

    2015-02-01

    We examine the kinematic structure of damped Lyman ? systems (DLAs) in a series of cosmological hydrodynamic simulations using the AREPO code. We are able to match the distribution of velocity widths of associated low-ionization metal absorbers substantially better than earlier work. Our simulations produce a population of DLAs dominated by haloes with virial velocities around 70 km s-1, consistent with a picture of relatively small, faint objects. In addition, we reproduce the observed correlation between velocity width and metallicity and the equivalent width distribution of Si II. Some discrepancies of moderate statistical significance remain; too many of our spectra show absorption concentrated at the edge of the profile and there are slight differences in the exact shape of the velocity width distribution. We show that the improvement over previous work is mostly due to our strong feedback from star formation and our detailed modelling of the metal ionization state.

  6. 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

  7. P-Value Precision and Reproducibility

    PubMed Central

    Boos, Dennis D.; Stefanski, Leonard A.

    2011-01-01

    Summary P-values are useful statistical measures of evidence against a null hypothesis. In contrast to other statistical estimates, however, their sample-to-sample variability is usually not considered or estimated, and therefore not fully appreciated. Via a systematic study of log-scale p-value standard errors, bootstrap prediction bounds, and reproducibility probabilities for future replicate p-values, we show that p-values exhibit surprisingly large variability in typical data situations. In addition to providing context to discussions about the failure of statistical results to replicate, our findings shed light on the relative value of exact p-values vis-a-vis approximate p-values, and indicate that the use of *, **, and *** to denote levels .05, .01, and .001 of statistical significance in subject-matter journals is about the right level of precision for reporting p-values when judged by widely accepted rules for rounding statistical estimates. PMID:22690019

  8. 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

  9. 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…

  10. Reproductive strategy, sexual development and attraction to facial characteristics

    PubMed Central

    Cornwell, R. Elisabeth; Law Smith, Miriam J; Boothroyd, Lynda G; Moore, Fhionna R; Davis, Hasker P; Stirrat, Michael; Tiddeman, Bernard; Perrett, David I

    2006-01-01

    Sexual reproduction strategies vary both between and within species in the level of investment in offspring. Life-history theories suggest that the rate of sexual maturation is critically linked to reproductive strategy, with high investment being associated with few offspring and delayed maturation. For humans, age of puberty and age of first sex are two developmental milestones that have been associated with reproductive strategies. Stress during early development can retard or accelerate sexual maturation and reproduction. Early age of menarche is associated with absence of younger siblings, absence of a father figure during early life and increased weight. Father absence during early life is also associated with early marriage, pregnancy and divorce. Choice of partner characteristics is critical to successful implementation of sexual strategies. It has been suggested that sexually dimorphic traits (including those evident in the face) signal high-quality immune function and reproductive status. Masculinity in males has also been associated with low investment in mate and offspring. Thus, women's reproductive strategy should be matched to the probability of male investment, hence to male masculinity. Our review leads us to predict associations between the rate of sexual maturation and adult preferences for facial characteristics (enhanced sexual dimorphism and attractiveness). We find for men, engaging in sex at an early age is related to an increased preference for feminized female faces. Similarly, for women, the earlier the age of first sex the greater the preference for masculinity in opposite-sex faces. When we controlled sexual dimorphism in male faces, the speed of sexual development in women was not associated with differences in preference for male facial attractiveness. These developmental influences on partner choice were not mediated by self-rated attractiveness or parental relationships. We conclude that individuals assort in preferences based on the rapidity of their sexual development. Fast developing individuals prefer opposite-sex partners with an increased level of sexually dimorphic facial characteristics. PMID:17118929

  11. 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

  12. Reproducing natural spider silks' copolymer behavior in synthetic silk mimics.

    PubMed

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

    2012-12-10

    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

  13. Masculinities, Sexualities and Child Sexual Abuse

    Microsoft Academic Search

    Annie Cossins

    Empirical evidence shows that child sexual abuse is overwhelmingly a male activity in that the majority of child sex offenders are male irrespective of the sex of the children they abuse. This sex specificity raises both a sex and gender question, as well as the epistemological question of how to characterise the relationship between male offenders and this particular crime.

  14. SEXUAL MISCONDUCT POLICY Case Western Reserve University

    E-print Network

    Yang, Sichun

    1 SEXUAL MISCONDUCT POLICY Case Western Reserve University Table of Contents Page Introduction 3 Definition and Examples 4 Sexual Harassment 4 Sexual Exploitation 4 Non-Consensual Sexual Contact or Activity 5 Forced Sexual Contact or Activity 5 Non-Consensual Sexual Intercourse 5 Forced Sexual Intercourse

  15. Asexual reproduction induces a rapid and permanent loss of sexual reproduction capacity in the rice fungal pathogen Magnaporthe oryzae: results of in vitro experimental evolution assays

    PubMed Central

    2012-01-01

    Background Sexual reproduction is common in eukaryotic microorganisms, with few species reproducing exclusively asexually. However, in some organisms, such as fungi, asexual reproduction alternates with episodic sexual reproduction events. Fungi are thus appropriate organisms for studies of the reasons for the selection of sexuality or clonality and of the mechanisms underlying this selection. Magnaporthe oryzae, an Ascomycete causing blast disease on rice, reproduces mostly asexually in natura. Sexual reproduction is possible in vitro and requires (i) two strains of opposite mating types including (ii) at least one female-fertile strain (i.e. a strain able to produce perithecia, the female organs in which meiosis occurs). Female-fertile strains are found only in limited areas of Asia, in which evidence for contemporary recombination has recently been obtained. We induced the forced evolution of four Chinese female-fertile strains in vitro by the weekly transfer of asexual spores (conidia) between Petri dishes. We aimed to determine whether female fertility was rapidly lost in the absence of sexual reproduction and whether this loss was controlled genetically or epigenetically. Results All the strains became female-sterile after 10 to 19 rounds of selection under asexual conditions. As no single-spore isolation was carried out, the observed decrease in the production of perithecia reflected the emergence and the invasion of female-sterile mutants. The female-sterile phenotype segregated in the offspring of crosses between female-sterile evolved strains and female-fertile wild-type strains. This segregation was maintained in the second generation in backcrosses. Female-sterile evolved strains were subjected to several stresses, but none induced the restoration of female fertility. This loss of fertility was therefore probably due to genetic rather than epigenetic mechanisms. In competition experiments, female-sterile mutants produced similar numbers of viable conidia to wild-type strains, but released them more efficiently. This advantage may account for the invasion of our populations by female-sterile mutants. Conclusions We show for the first time that, in the absence of sexual reproduction, female-sterile mutants of M. oryzae rice strains can arise and increase in abundance in asexual generations. This change in phenotype was frequent and probably caused by mutation. These results suggest that female fertility may have been lost rapidly during the dispersion of the fungus from Asia to the rest of the world. PMID:22458778

  16. 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

  17. Memories, fantasies and sexual victimization

    E-print Network

    Cockroft, Ronald Duane

    1992-01-01

    late nights, and her kindness and care during my harried hours and fatigue, this thesis would have never have come to completion. TABLE OF CONTENTS INTRODUCTION Freud's Views of Child Sexual Abuse Repression Sexual Fantasy in the Literature... related to sexual abuse than would non-abused individuals. Freud's Views of Child Sexual Abuse Early in his career, Sigmund Freud addressed the memories of childhood sexual experiences that his clients had related to him. He believed them to be true...

  18. Ecological divergence and sexual selection drive sexual size dimorphism in New World pitvipers (Serpentes: Viperidae).

    PubMed

    Hendry, C R; Guiher, T J; Pyron, R A

    2014-04-01

    Hypotheses for the origin and maintenance of sexual size dimorphism (SSD) fall into three primary categories: (i) sexual selection on male size, (ii) fecundity selection on female size and (iii) ecological selection for gender-specific niche divergence. We investigate the impact of these forces on SSD evolution in New World pitvipers (Crotalinae). We constructed a phylogeny from up to eight genes (seven mitochondrial, one nuclear) for 104 species of NW crotalines. We gathered morphological and ecological data for 82 species for comparative analyses. There is a strong signal of sexual selection on male size driving SSD, but less evidence for fecundity selection on female size across lineages. No support was found for allometric scaling of SSD (Rensch's rule), nor for directional selection for increasing male size (the Fairbairn-Preziosi hypothesis) in NW crotalines. Interestingly, arboreal lineages experience higher rates of SSD evolution and a pronounced shift to female-biased dimorphism. This suggests that fecundity selection on arboreal females exaggerates ecologically mediated dimorphism, whereas sexual selection drives male size in terrestrial lineages. We find that increasing SSD in both directions (male- and female-biased) decreases speciation rates. In NW crotalines, it appears that increasing magnitudes of ecologically mediated SSD reduce rates of speciation, as divergence accumulates within species among sexes, reducing adaptive divergence between populations leading to speciation. PMID:24597708

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

    PubMed Central

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

    2014-01-01

    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

  20. Sexual Behavior, Sexual Knowledge, and Sexual Attitudes of Emerging Adult Women: Implications for Working with Families

    ERIC Educational Resources Information Center

    Byno, Lucy H.; Mullis, Ronald L.; Mullis, Ann K.

    2009-01-01

    The purpose of this study was twofold: first, to examine the sexual behavior of emerging adult women in relation to their sexual knowledge, sexual attitudes, and perceptions of their parents' sexual attitudes; and second, to discuss the implications of this research in working with young adult women. Three hundred and sixty-four college-age women…

  1. Sexual scripts and sexual risk behaviors among Black heterosexual men: development of the Sexual Scripts Scale.

    PubMed

    Bowleg, Lisa; Burkholder, Gary J; Noar, Seth M; Teti, Michelle; Malebranche, David J; Tschann, Jeanne M

    2015-04-01

    Sexual scripts are widely shared gender and culture-specific guides for sexual behavior with important implications for HIV prevention. Although several qualitative studies document how sexual scripts may influence sexual risk behaviors, quantitative investigations of sexual scripts in the context of sexual risk are rare. This mixed methods study involved the qualitative development and quantitative testing of the Sexual Scripts Scale (SSS). Study 1 included qualitative semi-structured interviews with 30 Black heterosexual men about sexual experiences with main and casual sex partners to develop the SSS. Study 2 included a quantitative test of the SSS with 526 predominantly low-income Black heterosexual men. A factor analysis of the SSS resulted in a 34-item, seven-factor solution that explained 68% of the variance. The subscales and coefficient alphas were: Romantic Intimacy Scripts (? = .86), Condom Scripts (? = .82), Alcohol Scripts (? = .83), Sexual Initiation Scripts (? = .79), Media Sexual Socialization Scripts (? = .84), Marijuana Scripts (? = .85), and Sexual Experimentation Scripts (? = .84). Among men who reported a main partner (n = 401), higher Alcohol Scripts, Media Sexual Socialization Scripts, and Marijuana Scripts scores, and lower Condom Scripts scores were related to more sexual risk behavior. Among men who reported at least one casual partner (n = 238), higher Romantic Intimacy Scripts, Sexual Initiation Scripts, and Media Sexual Socialization Scripts, and lower Condom Scripts scores were related to higher sexual risk. The SSS may have considerable utility for future research on Black heterosexual men's HIV risk. PMID:24311105

  2. Multiresolution Reproducing Kernel Particle Method for Computational Fluid Dynamics

    E-print Network

    Liu, Wing Kam

    Multiresolution Reproducing Kernel Particle Method for Computational Fluid Dynamics Wing Kam Liu­ cal Method in Fluids. Abstract Multiresolution analysis based on Reproducing Kernel Particle Method in fluid dynamics. KEY WORDS: meshless kernel particle method, multiresolution analysis, wavelets

  3. A quasispecies approach to the evolution of sexual replication in unicellular organisms

    Microsoft Academic Search

    Emmanuel Tannenbaum; José F. Fontanari

    2008-01-01

    This study develops a simplified model describing the evolutionary dynamics of a population composed of obligate sexually\\u000a and asexually reproducing, unicellular organisms. The model assumes that the organisms have diploid genomes consisting of\\u000a two chromosomes, and that the sexual organisms replicate by first dividing into haploid intermediates, which then combine\\u000a with other haploids, followed by the normal mitotic division of

  4. The Implications of Sexual Narcissism for Sexual and Marital Satisfaction

    PubMed Central

    McNulty, James K.; Widman, Laura

    2013-01-01

    There is theoretical reason to believe narcissism is associated with a number of sexual behaviors and outcomes that affect both sexual and relationship satisfaction. Nevertheless, research on the association between personality and behavior demonstrates that personality traits, such as narcissism, only predict behavior in domains that activate the components of the personality system. Given that global assessments of narcissism do not capture the extent to which the components of narcissism are activated in the sexual domain, we examined the extent to which the facets of a domain-specific measure of sexual narcissism accounted for the trajectories of own and partner sexual and marital satisfaction over the first five years of 120 new marriages. Three of the four facets of sexual narcissism (sexual exploitation, sexual entitlement, and low sexual empathy) were negatively associated with both trajectories. The fourth facet (sexual skill) was positively associated with both trajectories. Notably, sexual satisfaction mediated the effect of every facet of sexual narcissism on marital satisfaction. A global assessment of narcissism was not associated with either trajectory of satisfaction. These findings highlight (1) the importance of narcissistic tendencies for sexual processes, (2) the benefits of using domain-specific measures of personality in research on sexual behavior, and (3) the importance of examining the implications of the specific facets of personality constructs. PMID:23297145

  5. The implications of sexual narcissism for sexual and marital satisfaction.

    PubMed

    McNulty, James K; Widman, Laura

    2013-08-01

    There is theoretical reason to believe narcissism is associated with a number of sexual behaviors and outcomes that affect both sexual and relationship satisfaction. Nevertheless, research on the association between personality and behavior demonstrates that personality traits, such as narcissism, only predict behavior in domains that activate the components of the personality system. Given that global assessments of narcissism do not capture the extent to which the components of narcissism are activated in the sexual domain, we examined the extent to which the facets of a domain-specific measure of sexual narcissism accounted for the trajectories of own and partner sexual and marital satisfaction over the first five years of 120 new marriages. Three of the four facets of sexual narcissism (sexual exploitation, sexual entitlement, and low sexual empathy) were negatively associated with both trajectories. The fourth facet (sexual skill) was positively associated with both trajectories. Notably, sexual satisfaction mediated the effect of every facet of sexual narcissism on marital satisfaction. A global assessment of narcissism was not associated with either trajectory of satisfaction. These findings highlight (1) the importance of narcissistic tendencies for sexual processes, (2) the benefits of using domain-specific measures of personality in research on sexual behavior, and (3) the importance of examining the implications of the specific facets of personality constructs. PMID:23297145

  6. Teen Sexual Health

    MedlinePLUS

    ... sex and how sex affects your health. Besides pregnancy, having sex puts you at risk of getting a sexually transmitted disease, such as herpes or genital warts, or HIV, the virus that causes AIDS. The only way ...

  7. 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 ...

  8. Sexual Orientation (For Parents)

    MedlinePLUS

    ... is also not considered a mental disorder or abnormality. Despite myths and misconceptions, there is no evidence ... their sexual orientation secret, even from friends and family who might be supportive. It can take time ...

  9. 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)

  10. Dealing with Sexual Problems

    MedlinePLUS

    ... the vulva (vulvectomy) Pelvic exenteration Sex and pelvic radiation therapy Sex and chemotherapy Sex and hormone therapy Surgery for breast cancer can affect sexuality, too Summary table of how ...

  11. 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)

  12. Evolutionary biology Sexual ornamentation

    E-print Network

    Richner, Heinz

    Evolutionary biology Sexual ornamentation reflects antibacterial activity of ejaculates in mallards the antibacterial activity of semen from mallard ducks (Anas platyrhynchos) and tested whether the bactericidal semen exhibits significant antibacterial activity, as measured by the in vitro capacity to kill

  13. Sexual Health and Reproduction

    NSDL National Science Digital Library

    Ingrid Waldron

    This activity provides questions and Web sites to guide student investigation of birth control methods, fetal development, risks of alcohol and smoking during pregnancy, changes during puberty, and HIV/AIDS and other sexually transmitted diseases.

  14. Sexual Assault against Females

    MedlinePLUS

    ... Summer Sports Clinic Training – Exposure – Experience (TEE) Tournament Wheelchair Games Winter Sports Clinic Locations Hospitals & Clinics Vet ... Sexual problems can be among the most long-standing problems experienced by women who are the victims ...

  15. 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

  16. Reproducibility of binary-mixture toxicity studies.

    PubMed

    Cedergreen, Nina; Kudsk, Per; Mathiassen, Solvejg Kopp; Sørensen, Helle; Streibig, Jens Carl

    2007-01-01

    Binary-mixture studies often are conducted with the aim of elucidating the effect of one specific chemical on the biological action of another. The results can be interpreted in relation to reference models by the use of response-surface analyses and isobolograms. The amount of data needed for these analyses is, however, extensive, and the experiments therefore rarely are repeated. In the present study, we investigate the reproducibility of isobole shapes of binary-mixture toxicity experiments in terms of deviation from the reference model of concentration addition (CA), dose-level dependence, and isobole asymmetry. We use data from four herbicide mixtures tested in three to five independent experiments on the aquatic test plant Lemna minor and the terrestrial plant Tripleurospermum inodorum. The results showed that the variation both within and among experiments was approximately half the size for the aquatic test system compared to the terrestrial system. As a consequence, a consistent deviation from CA could be obtained in three of four herbicide mixtures for L. minor, whereas this was only the case for one or two of the herbicide mixtures tested on T. inodorum. For one mixture on T. inodorum, both CA synergism and antagonism were detected. Dose-dependent effects could not be repeated consistently, just as the asymmetry found in some isoboles could not. The study emphasizes the importance of repeating mixture toxicity experiments, especially for test systems with large variability, and using caution when drawing biological conclusions from the test results. PMID:17269472

  17. RAPID COMMUNICATION VARROA JACOBSONI DOES REPRODUCE IN WORKER

    E-print Network

    Paris-Sud XI, Université de

    ) reported that Varroa jacobsoni greatly prefers drone over worker brood, and only reproduces in the drone brood of Apis cerana colonies in Sri Lanka and Indonesia. In Apis mellifera the mites also prefer drone cells, but can reproduce effectively in both worker and drone cells. The capacity to reproduce in worker

  18. Sexual violence in Lesotho.

    PubMed

    Brown, Lisanne; Thurman, Tonya; Bloem, Jeanette; Kendall, Carl

    2006-12-01

    The magnitude and characteristics of sexual violence in two urban areas of Lesotho are described based on a random household survey of 939 sexually active women aged 18-35. Sexual violence is defined as nonconsensual sex ranging from the use of threats and intimidation to unwanted touching and forced sex. Twenty-five percent of women surveyed reported ever being physically forced to have sex; 13 percent reported that forced sex was attempted; 31 percent said that they were touched against their will; and 11 percent reported being forced to touch a man's genitals. Boyfriends were the most common perpetrators of actual and attempted forced sex (66 percent and 44 percent, respectively); known community members were the most common perpetrators of touching the respondent against her will (52 percent). Currently married women and those with more education were less likely than others to report that sex was forced upon them by an intimate partner or by another type of perpetrator. Women living in areas where a program raising awareness about sexual violence was ongoing were more likely to report a history of sexual violence. Given the high prevalence of HIV in Lesotho, programs should address women's right to control their sexuality. PMID:17209284

  19. Is sexual monomorphism a predictor of polygynandry? Evidence from a social mammal, the collared peccary

    Microsoft Academic Search

    Jennifer D. Cooper; Peter M. Waser; Eric C. Hellgren; Timothy M. Gabor; J. A. DeWoody

    2011-01-01

    Sexual dimorphism is common in polygynous species, and there is clear evidence that both intra-sexual competition and female\\u000a preferences can drive the evolution of large body size in males. In contrast, sexual monomorphism is often argued to reflect\\u000a a relaxation of male mate competition or an intensification of resource competition among females. Alternatively, it might\\u000a imply opportunities for females to

  20. Pediatric sexuality: promoting normal sexual development in children.

    PubMed

    Smith, M

    1993-08-01

    Since the sexual revolution of the 1960s there has been an openness regarding sexual exploration that has resulted in an increase of sexually transmitted diseases and teenage pregnancies. Clinicians can mitigate the unhealthy results of such exploration through a therapeutic relationship with their patients. This article provides practical ways to approach and educate the pediatric patient and parent regarding normal sexual growth and development and the promotion of healthy, responsible sexual behavior. Using developmental theories as a foundation, sexuality is examined from birth through the adolescent years. PMID:8233152

  1. Professional perspectives on sexual sadism.

    PubMed

    McLawsen, Julia E; Jackson, Rebecca L; Vannoy, Steven D; Gagliardi, Gregg J; Scalora, Mario J

    2008-09-01

    Significant controversy surrounds the diagnosis of sexual sadism. Research suggests that many characteristics attributed to sexual sadists fail to differentiate sexual offenders with and without this diagnosis. Furthermore, when there are differences between sadists and nonsadists, "sadistic" features are frequently associated with nonsadists. Finally, diagnosticians appear to use idiosyncratic methods to diagnose sexual sadism. These findings raise concerns about the reliability and validity of a diagnosis of sexual sadism, particularly with respect to how professionals conceptualize this diagnosis. This study examines how professionals understand the relative importance of behaviors associated with sadistic versus nonsadistic sexual offending. Professionals rated behaviors according to their "essentialness" for this diagnosis. Results show that professionals rated behaviors associated with three out of four conceptualizations of sexual sadism as significantly more essential to making a diagnosis of sexual sadism, compared to behaviors associated with nonsadistic sexual offending. Results suggest that professionals reliably discriminate between sadistic and nonsadistic offense behaviors. PMID:18775840

  2. 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.

  3. Sexual coercion and the misperception of sexual intent?

    PubMed Central

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

    2010-01-01

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

  4. 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

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

    PubMed

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

    2004-05-01

    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

  6. SEXUAL HARASSMENT POLICY Office of Equal Opportunity

    E-print Network

    Dennett, Daniel

    SEXUAL HARASSMENT POLICY Office of Equal Opportunity Purpose: To establish uniform guidelines pertaining to sexual harassment. Revised: April 2014 Applicability: Sexual Harassment is a form and community members). This policy is summarized in the University's Sexual Misconduct/Assault Policy

  7. Sexual Assault Prevention Workshop Final Report

    E-print Network

    Marsh, David

    WGS 296A Sexual Assault Prevention Workshop Final Report Recommendations for Improving Sexual 14, 2009 #12;TABLE OF CONTENTS PART ONE: SEXUAL ASSAULT AT WASHINGTON AND LEE UNIVERSITY (W&L) ..............................1 CONTRIBUTING FACTORS FOR COLLEGE SEXUAL ASSAULT

  8. 49 CFR 1019.5 - Sexual harassment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    (a) Members and employees shall not engage in harassment on the basis of sex. Unwelcome sexual advances, requests for sexual favors, and other verbal or physical conduct of a sexual nature constitute sexual harassment...

  9. Perceptions of Sexuality as Related to Sexual Functioning and Sexual Risk in Women with Different Types of Childhood Abuse Histories

    Microsoft Academic Search

    Kelly A. Schloredt; Julia R. Heiman

    2003-01-01

    Perceptions of one's sexuality, self-reported sexual functioning, and sexual risk were examined in a community sample of 148 women with histories of either childhood sexual abuse (n = 26), both childhood sexual and physical abuse (n = 44), and neither form of abuse (n = 78). Controlling for depression and anxiety, the groups did not differ on sexual desire, arousal\\/orgasm,

  10. On the evolutionary origins of differences in sexual preferences.

    PubMed

    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

  11. 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.

  12. The problem of sexual bipotentiality as exemplified by teleosts R. REINBOTH

    E-print Network

    Boyer, Edmond

    The problem of sexual bipotentiality as exemplified by teleosts R. REINBOTH Institut für Zoo there has been a controversy as to whether sex steroids or (hypothetical) inductor substances play a major this discussion. It is proposed that the use of ambisexual teleost species as unique models of sexual organization

  13. The sexual differentiation of Cannabis sativa L.: A morphological and molecular study

    Microsoft Academic Search

    V. M. Cristiana Moliterni; Luigi Cattivelli; P. Ranalli; Giuseppe Mandolino

    2004-01-01

    Summary  Cannabis sativa L. is a dioecious species with sexual dimorphism occurring in a late stage of plant development. Sex is determined by heteromorphic chromosomes (X and Y): male is the heterogametic sex (XY) and female is the homogametic one (XX). The sexual phenotype of Cannabis often shows some flexibility leading to the differentiation of hermaphrodite flowers or bisexual inflorescences (monoecious

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

    E-print Network

    McCracken, Kevin G.

    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

  15. 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

  16. Sexual selection and the differential effect of polyandry

    PubMed Central

    Collet, Julie; Richardson, David S.; Worley, Kirsty; Pizzari, Tommaso

    2012-01-01

    In principle, widespread polyandry (female promiscuity) creates potential for sexual selection in males both before and after copulation. However, the way polyandry affects pre- and postcopulatory episodes of sexual selection remains little understood. Resolving this fundamental question has been difficult because it requires extensive information on mating behavior as well as paternity for the whole male population. Here we show that in replicate seminatural groups of red junglefowl, Gallus gallus, polyandry eroded variance in male mating success, which simultaneously weakened the overall intensity of sexual selection but increased the relative strength of postcopulatory episodes. We further illustrate the differential effect of polyandry on pre- and postcopulatory sexual selection by considering the case of male social status, a key determinant of male reproductive success in this species. In low-polyandry groups, however, status was strongly sexually selected before copulation because dominants mated with more females. In high-polyandry groups, sexual selection for status was weakened and largely restricted after copulation because dominants defended paternity by mating repeatedly with the same female. These results reveal polyandry as a potent and dynamic modulator of sexual selection episodes. PMID:22592795

  17. Sexual Narcissism and the Perpetration of Sexual Aggression

    Microsoft Academic Search

    Laura Widman; James K. McNulty

    2010-01-01

    Despite indirect evidence linking narcissism to sexual aggression, studies directly examining this relationship have yielded\\u000a inconsistent results. Likely contributing to such inconsistencies, prior research has used global measures of narcissism not\\u000a sensitive to whether the components of narcissism are activated in sexual versus non-sexual domains. The current research\\u000a avoided such problems by using a measure of sexual narcissism to predict

  18. [Sexuality in adolescents].

    PubMed

    Molina, R; Araa, S; Ibazeta, G; Jordan, P; Lagos, E

    1987-01-01

    A survey of knowledge, attitude, and practices regarding human reproduction and sexuality was undertaken in 2 groups of secondary school students in Chile to assess whether greater knowledge of reproduction and sexuality is associated with greater permissiveness and earlier initiation of sexual activity. Students in 2 public schools, 1 coeducational and 1 for female students only, were of lower middle class background, while students at the coeducational private school were of higher socioeconomic status. An anonymous, semiclosed questionnaire was administered to students in the 3 schools. The schools were selected because their directors agreed to permit the study. 14.8% of the 351 public school students were aged 14 or under and 77.8% were 15-18, while 99.5% of the 197 private school students were aged 15-18. The students' levels of knowledge of human reproduction and sexuality were measured through direct personal assessments by the students themselves and through 21 questions to confirm the assessments. At least 93% of students in all schools said their level of knowledge was medium or high, but the test indicated that only 64% of public school students and 75% of private school students actually had medium or high levels of knowledge. 45.9% of private and 27.9% of public school students felt the information they received from their schools about sexuality was adequate, while 41.9% of private and 60.9% of public school students felt it was insufficient. There were no significant differences in the opinions of the 2 groups of students concerning premarital sex, but the reasons given by the private school students to explain their attitudes expressed a greater sense of commitment to the partner, while those of the public school students tended to be more functional. Among public school students, 38.7% of males and 9.7% of females reported having had sexual relations, while among private school students, 17.7% of males and 4.4% of females reported having done so. No significant differences were reported in the age of initiating sexual activity in the 2 groups. Students in the school with the highest overall level of knowledge of human reproduction and sexuality had lower overall levels of sexual activity. PMID:12269033

  19. Accurate measurements of dynamics and reproducibility in small genetic networks

    PubMed Central

    Dubuis, Julien O; Samanta, Reba; Gregor, Thomas

    2013-01-01

    Quantification of gene expression has become a central tool for understanding genetic networks. In many systems, the only viable way to measure protein levels is by immunofluorescence, which is notorious for its limited accuracy. Using the early Drosophila embryo as an example, we show that careful identification and control of experimental error allows for highly accurate gene expression measurements. We generated antibodies in different host species, allowing for simultaneous staining of four Drosophila gap genes in individual embryos. Careful error analysis of hundreds of expression profiles reveals that less than ?20% of the observed embryo-to-embryo fluctuations stem from experimental error. These measurements make it possible to extract not only very accurate mean gene expression profiles but also their naturally occurring fluctuations of biological origin and corresponding cross-correlations. We use this analysis to extract gap gene profile dynamics with ?1?min accuracy. The combination of these new measurements and analysis techniques reveals a twofold increase in profile reproducibility owing to a collective network dynamics that relays positional accuracy from the maternal gradients to the pair-rule genes. PMID:23340845

  20. How Teen Sexual Behavior Responds to Sexually Transmitted Disease Risks

    Microsoft Academic Search

    Amy Elizabeth Corman

    2002-01-01

    This paper examines how teen sexual behavior responds to associated disease infection risks using the biannual 1993-99 waves of the Youth Risk Behavior Surveys. We estimate the effect of state level rates of AIDS and other sexually transmitted diseases on sexual behavior with probit regressions for the decision to have sex during the previous three months along with ordinary least

  1. Sexual abstinence and the Sexual Abstinence Behavior Scale

    Microsoft Academic Search

    Anne E. Norris; Leslie F. Clark; Sondra Magnus

    2003-01-01

    Introduction: Nurses may choose to promote sexual abstinence, particularly when they are working with young adolescents. However, it is difficult to know how to intervene because sexual abstinence has not been well defined in the literature. The purpose of this study was to evaluate the psychometrics of a four-item measure of sexual abstinence behavior (the SABS) that both registered nurses

  2. 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…

  3. Sexual Oncology: Sexual Health Issues in Women with Cancer

    Microsoft Academic Search

    Michael L. Krychman; Leanne Pereira; Jeanne Carter; Alison Amsterdam

    2006-01-01

    Sexual problems are widespread among female cancer patients and survivors. Dysfunction may result from various oncologic therapies such as surgery, radiation therapy, chemotherapy, hormonal manipulation, and cytostatic medication. Additionally, psychologic distress that the patient or her partner experiences during diagnosis and treatment of malignancy can impair a healthy female sexual response cycle. A sexual rehabilitation program in an oncology setting

  4. 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…

  5. Motivations and sexual attitudes, experiences, and behavior of sexuality professionals.

    PubMed

    Luria, Mijal; Byers, E Sandra; Voyer, Susan D; Mock, Moshe

    2013-01-01

    This study examined the motivations for entering the field and sexual attitudes, experiences, and behavior of an international group of sexuality professionals. Participants were 252 individuals attending the XVII World Congress of Sexology who completed a questionnaire in English, Spanish or French. Most participants' reported professional rather than personal motivations for entering the field in addition to interest. On average, participants reported little sexual communication with their parents as children. About one-third had experienced unwanted sexual activity as a child. Participants were mostly accepting of a range of sexual activities, although they were less accepting of some behaviors than of others. Twelve of the participants who had engaged in sexual activity with a casual or anonymous partner in the previous 2 years had not used a condom consistently. Participants reported high sexual satisfaction and good sexual communication with their partner. Nevertheless, 45% of the women and 35% of the men reported regularly experiencing one or more sexual problems. Few participants reported that their profession affected their sexual functioning negatively; in contrast most reported that it had positive effects on their sexual functioning. These results suggest that there are few differences between sexuality professionals and the general public. PMID:23252637

  6. Sexual responding of “nonrapists” to aggressive sexual themes: Normative data

    Microsoft Academic Search

    William D. Murphy; Mary R. Haynes; Emily M. Coleman; Barry Flanagan

    1985-01-01

    The present study presents data relevant to the sexual responding to aggressive cues of a large sample of nonrapist males recruited from the community. Two hundred three subjects received physiological assessment of sexual arousal to heterosexual and rape stimuli. Results indicated that under instructions not to interfere with sexual responding, approximately 80% of the nonrapists would be correctly classified, which

  7. Psychopathy and Deviant Sexual Arousal in Incarcerated Sexual Offenders

    Microsoft Academic Search

    RALPH C. SERIN; P. BRUCE MALCOLM; ARUNIMA KHANNA; HOWARD E. BARBAREE

    1994-01-01

    This study investigates the relationship between psychopathy and deviant sexual arousal in a sample of 65 sexual offenders, with approximately equal numbers of rapists and child molesters. Psychopathy, measured by the Psychopathy Checklist-Revised and phallometric indexes of deviant sexual arousal were significantly correlated, r(63) =.28, p <. 02. Differentiating between rapists, extrafamilial pedophiles, and incest offenders revealed that this relationship,

  8. Were Adolescent Sexual Offenders Children with Sexual Behavior Problems?

    Microsoft Academic Search

    David L. Burton

    2000-01-01

    This article compares responses of three groups of incarcerated adolescents who admitted to sexual offending in an anonymous survey project on measures of trauma, sexual offending, the relationship between trauma and perpetration, and adjudication status. The first group admitted to sexual offending before the age of 12 only (n = 48), the second after the age of 12 only (n

  9. Sexual and emotional variables influencing sexual response to erotica

    Microsoft Academic Search

    Eric Koukounas; Marita McCabe

    1997-01-01

    This study was designed to evaluate the relative contribution of attention and emotional responses to the sexual response to erotica. Self reported levels of sexual arousal, attention, and emotional responses were measured after 20 men and 20 women viewed a series of erotic film segments. Men and women reported greater sexual arousal to erotica when they became absorbed in the

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

    E-print Network

    Crews, David

    of sexual behavior following castration. In a second experiment, we tested whether male mice heterozygous and experience. © 1998 Academic Press Key Words: progesterone receptor; male; sexual be- havior; castration of experienced males to exhibit sexual behaviors following castration, and variation in the sensitivity of males

  11. 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

  12. Sexual selection explains sex-specific growth plasticity and positive allometry for sexual size dimorphism in a reef fish

    PubMed Central

    Walker, Stefan P. W.; McCormick, Mark I.

    2009-01-01

    In 1950, Rensch noted that in clades where males are the larger sex, sexual size dimorphism (SSD) tends to be more pronounced in larger species. This fundamental allometric relationship is now known as ‘Rensch's rule’. While most researchers attribute Rensch's rule to sexual selection for male size, experimental evidence is lacking. Here, we suggest that ultimate hypotheses for Rensch's rule should also apply to groups of individuals and that individual trait plasticity can be used to test those hypotheses experimentally. Specifically, we show that in the sex-changing fish Parapercis cylindrica, larger males have larger harems with larger females, and that SSD increases with harem size. Thus, sexual selection for male body size is the ultimate cause of sexual size allometry. In addition, we experimentally illustrate a positive relationship between polygyny potential and individual growth rate during sex change from female to male. Thus, sexual selection is the ultimate cause of variation in growth rate, and variation in growth rate is the proximate cause of sexual size allometry. Taken together, our results provide compelling evidence in support of the sexual selection hypothesis for Rensch's rule and highlight the potential importance of individual growth modification in the shaping of morphological patterns in Nature. PMID:19553253

  13. Childhood Sexual Abuse and Suicide

    MedlinePLUS

    ... D. (2005). Adult perpetrator gender asymmetries in child sexual assault victim selection: Results from the 2000 National Incident- ... Washington, DC: Institute of Medicine. One third of sexual assault victims were under the age of 12.1 ...

  14. Sexual Harassment in the Workplace.

    ERIC Educational Resources Information Center

    Maypole, Donald E.; Skaine, Rosemarie

    1983-01-01

    Reviews the literature on sexual harassment to determine the issues the problem raises, its social contexts, and the resources available to working women. Examined the implications of sexual harassment for social work practice, policy, and research. (JAC)

  15. 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...

  16. Helping Teens Resist Sexual Pressure

    MedlinePLUS

    Healthy Children > Ages & Stages > Teen > Dating & Sex > Helping Teens Resist Sexual Pressure Ages & Stages Listen Español Text Size Email Print Share Helping Teens Resist Sexual Pressure Article Body Teens are more ...

  17. The misperception of sexual interest.

    PubMed

    Perilloux, Carin; Easton, Judith A; Buss, David M

    2012-02-01

    In the current study (N = 199), we utilized a speed-meeting methodology to investigate misperceptions of sexual interest. This method allowed us to evaluate the magnitude of men's overperception of women's sexual interest, to examine whether and how women misperceive men's sexual interest, and to assess individual differences in susceptibility to sexual misperception. We found strong support for the prediction that women would underestimate men's sexual interest. Men who were more oriented toward short-term mating strategies or who rated themselves more attractive were more likely to overperceive women's sexual interest. The magnitude of men's overperception of women's sexual interest was predicted by the women's physical attractiveness. We discuss implications of gender differences and within-sex individual differences in susceptibility to sexual misperception. PMID:22261567

  18. Sexual assault in the military.

    PubMed

    Castro, Carl Andrew; Kintzle, Sara; Schuyler, Ashley C; Lucas, Carrie L; Warner, Christopher H

    2015-07-01

    Military sexual assault is a pervasive problem throughout the military services, despite numerous initiatives to end it. No doubt the military's lack of progress stems from the complexity of sexual assaults, yet in order to develop effective strategies and programs to end sexual assault, deep understanding and appreciation of these complexities are needed. In this paper, we describe the root causes and numerous myths surrounding sexual assault, the military cultural factors that may unintentionally contribute to sexual assault, and the uncomfortable issues surrounding sexual assault that are often ignored (such as the prevalence of male sexual assault within the military). We conclude by offering a broad, yet comprehensive set of recommendations that considers all of these factors for developing effective strategies and programs for ending sexual assault within in the military. PMID:25980511

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

    PubMed

    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

  20. 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

  1. Conditioned sexual arousal in a nonhuman primate.

    PubMed

    Snowdon, Charles T; Tannenbaum, Pamela L; Schultz-Darken, Nancy J; Ziegler, Toni E; Ferris, Craig F

    2011-05-01

    Conditioning of sexual arousal has been demonstrated in several species from fish to humans but has not been demonstrated in nonhuman primates. Controversy exists over whether nonhuman primates produce pheromones that arouse sexual behavior. Although common marmosets copulate throughout the ovarian cycle and during pregnancy, males exhibit behavioral signs of arousal, demonstrate increased neural activation of anterior hypothalamus and medial preoptic area, and have an increase in serum testosterone after exposure to odors of novel ovulating females suggestive of a sexually arousing pheromone. Males also have increased androgens prior to their mate's ovulation. However, males presented with odors of ovulating females demonstrate activation of many other brain areas associated with motivation, memory, and decision making. In this study, we demonstrate that male marmosets can be conditioned to a novel, arbitrary odor (lemon) with observation of erections, and increased exploration of the location where they previously experienced a receptive female, and increased scratching in post-conditioning test without a female present. This conditioned response was demonstrated up to a week after the end of conditioning trials, a much longer lasting effect of conditioning than reported in studies of other species. These results further suggest that odors of ovulating females are not pheromones, strictly speaking and that marmoset males may learn specific characteristics of odors of females providing a possible basis for mate identification. PMID:21029736

  2. 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

  3. Beyond Sexual Orientation: Integrating Gender/Sex and Diverse Sexualities via Sexual Configurations Theory.

    PubMed

    van Anders, Sari M

    2015-07-01

    Sexual orientation typically describes people's sexual attractions or desires based on their sex relative to that of a target. Despite its utility, it has been critiqued in part because it fails to account for non-biological gender-related factors, partnered sexualities unrelated to gender or sex, or potential divergences between love and lust. In this article, I propose Sexual Configurations Theory (SCT) as a testable, empirically grounded framework for understanding diverse partnered sexualities, separate from solitary sexualities. I focus on and provide models of two parameters of partnered sexuality-gender/sex and partner number. SCT also delineates individual gender/sex. I discuss a sexual diversity lens as a way to study the particularities and generalities of diverse sexualities without privileging either. I also discuss how sexual identities, orientations, and statuses that are typically seen as misaligned or aligned are more meaningfully conceptualized as branched or co-incident. I map out some existing identities using SCT and detail its applied implications for health and counseling work. I highlight its importance for sexuality in terms of measurement and social neuroendocrinology, and the ways it may be useful for self-knowledge and feminist and queer empowerment and alliance building. I also make a case that SCT changes existing understandings and conceptualizations of sexuality in constructive and generative ways informed by both biology and culture, and that it is a potential starting point for sexual diversity studies and research. PMID:25772652

  4. Attachment insecurities and women's sexual function and satisfaction: the mediating roles of sexual self-esteem, sexual anxiety, and sexual assertiveness.

    PubMed

    Brassard, Audrey; Dupuy, Emmanuelle; Bergeron, Sophie; Shaver, Phillip R

    2015-01-01

    We examined the potential role of three mediators--sexual self-esteem, sexual anxiety, and sexual assertiveness--of the association between romantic attachment insecurities (anxiety and avoidance) and two aspects of women's sexual functioning: sexual function and sexual satisfaction. A sample of 556 women aged 18 to 30 agreed to complete an online series of validated questionnaires assessing attachment insecurities and several aspects of sexual functioning. Lower sexual self-esteem and higher sexual anxiety mediated the associations between attachment anxiety and lower sexual function and satisfaction. Lower sexual self-esteem and higher sexual anxiety also partially mediated the links between attachment-related avoidance and the two sexual functioning variables. Sexual assertiveness, however, did not mediate these associations. A significant interaction between attachment anxiety and avoidance was also found to predict sexual satisfaction, with women high in avoidance and low in anxiety being the least satisfied. Results are discussed in terms of theoretical and clinical implications. PMID:24350570

  5. [Child sexual abuse].

    PubMed

    Fegert, Jörg M

    2007-01-01

    The present paper gives an overview on the development of professional discourse on sexual abuse over the last 20 years in the field of child protection. After the introduction, definitions from different professional perspectives (civil law, criminal law, psychotherapy, counseling, etc.) are given. Based on these definitions an epidemiological range of prevalence figures is described. In the literature, rates ranging from 6 to 25 % in girls and 2 to 8 % in boy as victims of sexual abuse can be observed. Psychiatric consequences of sexual abuse are described based on an overview of the literature. Diagnostic approaches to posttraumatic problems are discussed and distinguished from obsolete measures. Some neurobiological findings are presented. Finally the foundations of counseling, psychotherapy and pharmacotherapy of behavioral of symptoms and PTSD are discussed on the bases of a literature review of controlled clinical trials. In conclusion, further developments in psychotherapy and research are discussed for the German practical child protection field. PMID:17177097

  6. Television and adolescent sexuality.

    PubMed

    Brown, J D; Childers, K W; Waszak, C S

    1990-01-01

    Existing studies of the sexual content of television programming and advertising and the effects of this content on adolescent viewers are reviewed. Content studies show that the frequency of sexual references have increased in the past decade and are increasingly explicit. Studies of the effects of this content, while scarce, suggest that adolescents who rely heavily on television for information about sexuality will have high standards of female beauty and will believe that premarital and extramarital intercourse with multiple partners is acceptable. They are unlikely to learn about the need for contraceptives as a form of protection against pregnancy or disease. Suggestions for future research and trends in television programming policies are explored. PMID:2307597

  7. ORIGINAL PAPER Predicting Sexual Problems in Women: The Relevance of Sexual

    E-print Network

    ORIGINAL PAPER Predicting Sexual Problems in Women: The Relevance of Sexual Excitation and Sexual-clinical sample of 540 hetero- sexual women were used to examine the relationships between scores on the Sexual Excitation/Sexual Inhibition Inventory for Women (SESII-W) and ratings of current sexual problems, lifetime

  8. Reproductive skew drives patterns of sexual dimorphism in sponge-dwelling snapping shrimps.

    PubMed

    Chak, Solomon Tin Chi; Duffy, J Emmett; Rubenstein, Dustin R

    2015-06-22

    Sexual dimorphism is typically a result of strong sexual selection on male traits used in male-male competition and subsequent female choice. However, in social species where reproduction is monopolized by one or a few individuals in a group, selection on secondary sexual characteristics may be strong in both sexes. Indeed, sexual dimorphism is reduced in many cooperatively breeding vertebrates and eusocial insects with totipotent workers, presumably because of increased selection on female traits. Here, we examined the relationship between sexual dimorphism and sociality in eight species of Synalpheus snapping shrimps that vary in social structure and degree of reproductive skew. In species where reproduction was shared more equitably, most members of both sexes were physiologically capable of breeding. However, in species where reproduction was monopolized by a single individual, a large proportion of females-but not males-were reproductively inactive, suggesting stronger reproductive suppression and conflict among females. Moreover, as skew increased across species, proportional size of the major chela-the primary antagonistic weapon in snapping shrimps-increased among females and sexual dimorphism in major chela size declined. Thus, as reproductive skew increases among Synalpheus, female-female competition over reproduction appears to increase, resulting in decreased sexual dimorphism in weapon size. PMID:26041357

  9. Buspirone and Paraphilic Sexual Behavior.

    ERIC Educational Resources Information Center

    Fedoroff, J. Paul; Fedoroff, Ingrid C.

    1992-01-01

    Reviews literature concerning buspirone's effect on sexual functioning. Presents three hypotheses: that buspirone's facilitation of sexual functioning is not solely a result of its anxiolytic effects; that buspirone facilitates nonparaphilc arousal but inhibits paraphilic sexual arousal; and that buspirone's efficacy in reducing paraphilic arousal…

  10. Sexual Trauma, Spirituality, and Psychopathology

    ERIC Educational Resources Information Center

    Krejci, Mark J.; Thompson, Kevin M.; Simonich, Heather; Crosby, Ross D.; Donaldson, Mary Ann; Wonderlich, Stephen A.; Mitchell, James E.

    2004-01-01

    This study assessed the association between spirituality and psychopathology in a group of sexual abuse victims and controls with a focus on whether spirituality moderated the association between sexual trauma and psychopathology. Seventy-one sexual trauma victims were compared to 25 control subjects on spiritual well-being, the Eating Disorder…

  11. Harvard University Sexual Harassment and

    E-print Network

    harassment may include statements made by telephone, email or other electronic form, whether directlyHarvard University Sexual Harassment and Drug-Free Workplace Distributed by Harvard Labor of sexual harassment. Sexual harassment in the workplace is discriminatory, unlawful, denies respect

  12. Sexuality Education as a Ministry

    ERIC Educational Resources Information Center

    Davis, Melanie J.

    2011-01-01

    The author describes her development from being her religious congregation's sexuality educator to completing doctoral studies and finding her place in the professional sexuality education community. She equates sexuality education to a ministry that reaches out to those in need of knowledge.

  13. 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…

  14. 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,…

  15. [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

  16. ORIGINAL PAPER Patterns of Sexual Arousal in Homosexual, Bisexual, and

    E-print Network

    , psycho- physiological studies, examining the association between sexual orientation and sexual arousal of sexual arousal. Keywords Sexual arousal Á Sexual orientation Á Bisexuality Á Psychophysiology, especially when sexual orientation is assessed in terms of fantasies, attraction, and behavior. In contrast

  17. Neuroendocrine contributions to sexual partner preference in birds Elizabeth Adkins-Regan

    E-print Network

    preference Zebra finch Japanese quail Estradiol Aromatase inhibitor Androgen receptor antagonist Sexual, and in socially monogamous species, most pairs consist of a female and a male. In tests designed to measure

  18. Cloning plants by seeds: Inheritance models and candidate genes to increase fundamental knowledge for engineering apomixis in sexual crops.

    PubMed

    Pupilli, Fulvio; Barcaccia, Gianni

    2012-06-30

    Apomixis is desirable in agriculture as a reproductive strategy for cloning plants by seeds. Because embryos derive from the parthenogenic development of apomeiotic egg cells, apomixis excludes fertilization in addition to meiotic segregation and recombination, resulting in offspring that are exact replicas of the parent. Introgression of apomixis from wild relatives to crop species and transformation of sexual genotypes into apomictically reproducing ones are long-held goals of plant breeding. In fact, it is generally accepted that the introduction of apomixis into agronomically important crops will have revolutionary implications for agriculture. This review deals with the current genetic and molecular findings that have been collected from model species to elucidate the mechanisms of apomeiosis, parthenogenesis and apomixis as a whole. Our goal is to critically determine whether biotechnology can combine key genes known to control the expression of the processes miming the main components of apomixis in plants. Two natural apomicts, as the eudicot Hypericum perforatum L. (St. John's wort) and the monocot Paspalum spp. (crowngrass), and the sexual model species Arabidopsis thaliana are ideally suited for such investigations at the genomic and biotechnological levels. Some novel views and original concepts have been faced on this review, including (i) the parallel between Y-chromosome and apomixis-bearing chromosome (e.g., comparative genomic analyses revealed common features as repression of recombination events, accumulation of transposable elements and degeneration of genes) from the most primitive (Hypericum-type) to the most advanced (Paspalum-type) in evolutionary terms, and (ii) the link between apomixis and gene-specific silencing mechanisms (i.e., likely based on chromatin remodelling factors), with merging lines of evidence regarding the role of auxin in cell fate specification of embryo sac and egg cell development in Arabidopsis. The production of engineered plants exhibiting apomictic-like phenotypes is critically reviewed and discussed. PMID:21906637

  19. Treating sexual dysfunction associated with prior sexual trauma.

    PubMed

    McCarthy, B W

    1990-01-01

    Negative, confusing, guilt-inducing, or traumatic sexual experiences are almost universal for both females and males. Guidelines are presented for assessing sexual trauma using the medium of the detailed sexual history. The cognitive-behavioral treatment strategy considers past trauma in the context of the present sexual dysfunction rather than an issue to be dealt with first or separately. The guiding principles are to teach the person to be a "survivor" rather than a "victim" and to help the couple develop a functional and satisfying sexual style because "living well is the best revenge." PMID:2246791

  20. The sexual habitus of transgender men: negotiating sexuality through gender.

    PubMed

    Schilt, Kristen; Windsor, Elroi

    2014-01-01

    In this article, the authors consider how trans men's decisions about physical body modifications impact their sense of themselves as gendered and sexual actors. Based on interviews with 74 trans men, the authors explore how their embodiment, gender identity, erotic ideation, lifetime of sexual practices, and domain of potential partners-what the authors term "sexual habitus"-can be affirmed, transformed, or challenged as their embodiment changes. These changes underscore the dynamic relationship between gender and sexuality and illustrate how bodies matter in sexual trajectories across the life course. PMID:24392744

  1. Independently Evolving Species in Asexual Bdelloid Rotifers

    Microsoft Academic Search

    Diego Fontaneto; Elisabeth A. Herniou; Chiara Boschetti; Manuela Caprioli; Giulio Melone; Claudia Ricci; Timothy G. Barraclough

    2007-01-01

    Asexuals are an important test case for theories of why species exist. If asexual clades displayed the same pattern of discrete variation as sexual clades, this would challenge the traditional view that sex is necessary for diversification into species. However, critical evidence has been lacking: all putative examples have involved organisms with recent or ongoing histories of recombination and have

  2. Sexual Coercion and Sexual Violence at First Intercourse Associated with Sexually Transmitted Infections

    PubMed Central

    Williams, Corrine M.; Clear, Emily R.; Coker, Ann L.

    2014-01-01

    Background Violence against women has been associated with subsequent risky sexual behaviors and sexually transmitted infections. We explored whether sexual coercion or violence at first intercourse was associated with self-reported sexually transmitted infections (STIs). Methods Using nationally representative data from the 2006–2010 National Survey of Family Growth, we analyzed female respondents ages 18–44 (n=9,466) who answered questions on coercion at first intercourse (wantedness, voluntariness and types of force used) and STIs using logistic regression analyses. We explored degrees of coercion, which we label as neither, sexual coercion (unwanted or nonphysical force), or sexual violence (involuntary or physical force). Results Eighteen percent of US women reported sexual coercion and 8.4% experienced sexual violence at first intercourse. Compared with women who experienced neither, the odds of reporting a STI was significantly greater for women who experienced sexual coercion (OR: 1.27, 95% CI: 1.01–1.60), after controlling for all variables. The association between sexual violence at first intercourse and STIs (OR: 1.20, 95% CI: 0.91–1.57) appeared to be attenuated by subsequent sexual violence. Conclusions Understanding that women who reported a variety of coercive sexual experiences are more likely to have contracted an STI may indicate a need to focus on the broader continuum of sexual violence to fully understand the impact of even subtle forms of violence on women’s health. In addition, focusing on subsequent sexual behaviors and other negative consequences remains important in order to improve the sexual health of women who have experienced coercive sexual intercourse. PMID:24275726

  3. College students' sexual attitudes and behaviors: implications for sexuality education.

    PubMed

    Feigenbaum, R; Weinstein, E; Rosen, E

    1995-11-01

    This study of sexual attitudes and behaviors of students in a large northeastern community college was undertaken in partial response to an outspoken community group's claims that the sexuality education courses being taught at the school were undermining the morality of its young adults and encouraging early sexual activity. Findings from 1,825 pretest respondents in human sexuality and general health courses indicated that more than 80% of the students had experienced sexual intercourse before they took the courses. In a posttest comparison with 1,456 of the same students, the authors found no significant changes in the number of students who were sexually active or in their attitudes about such issues as abortion and premarital, casual, or oral sex. Statistically significant changes did occur in human sexuality students' attitudes and behaviors about safer sex, having fewer sex partners, and using condoms and spermicides. PMID:8543724

  4. Operationalizing the concept of sexuality comfort: applications for sexuality educators.

    PubMed

    Graham, C A; Smith, M M

    1984-12-01

    Thirty-two high school and college educators participated in a study designed to operationalize the concept of sexuality comfort. Research questions asked were: "What is the nature of sexuality comfort?" and "Can the concept, of sexuality comfort be defined operationally?" An interview guide developed with input from an expert panel of health/sexuality educators and semanticists facilitated data collection. Data were categorized and tabulated through a systematic process. This coding process, performed by independent coders, yielded 97.2% reliability. Based on the results, an operational definition of sexuality comfort was delineated. Because an operational definition is one which tells what to do to experience the thing defined, the operational definition of sexuality comfort has immediate practical applications to preparation programs for prospective sexuality educators as well as those currently working in the field. PMID:6569283

  5. 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

  6. Discussion Guide for the Sexually Explicit Educational Video Sexuality Reborn: Sexuality Following Spinal Cord Injury

    Microsoft Academic Search

    Mitchell S. Tepper

    1997-01-01

    The use of sexually explicit media in education is a sensitive teaching area because of the range of adverse reactions sexually graphic images may evoke. The person planning to use a sexually explicit video needs to create a safe environment with time for discussion and they must be prepared to facilitate discussion that will elicit reactions and help viewers deal

  7. 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…

  8. Attempts to reproduce vacuolar myelinopathy in domestic swine and chickens.

    PubMed

    Lewis-Weis, Lynn A; Gerhold, Richard W; Fischer, John R

    2004-07-01

    Avian vacuolar myelinopathy (AVM) was first recognized as a cause of bald eagle (Haliaeetus leucocephalus) mortality in 1994 in Arkansas (USA) and has since caused over 90 bald eagle and numerous American coot (Fulica americana) mortalities in five southeastern states. The cause of AVM remains undetermined but is suspected to be a biotoxin. Naturally occurring AVM has been limited to wild waterbirds, raptors, and one species of shorebird, and has been reproduced experimentally in red-tailed hawks (Buteo jamaicensis). In this study, chickens and swine were evaluated for susceptibility to vacuolar myelinopathy with the intent of developing animal models for research and to identify specific tissues in affected coots that contain the causative agent. Additionally, submerged, aquatic vegetation, primarily hydrilla (Hydrilla verticillata), and associated material collected from a reservoir during an AVM outbreak was fed to chickens in an effort to reproduce the disease. In two separate experiments, six 4-wk-old leghorn chickens and ten 5-wk-old leghorn chickens were fed coot tissues. In a third experiment, five 3-mo-old domestic swine and one red-tailed hawk, serving as a positive control, were fed coot tissues. In these experiments, treatment animals received tissues (brain, fat, intestinal tract, kidney, liver, and/or muscle) from coots with AVM lesions collected at a lake during an AVM outbreak. Negative control chickens and one pig received tissues from coots without AVM lesions that had been collected at a lake where AVM has never been documented. In a fourth experiment, eight 3-wk-old leghorn chickens were fed aquatic vegetation material. Four chickens received material from the same lake from which coots with AVM lesions were collected for the previous experiments, and four control chickens were fed material from the lake where AVM has never been documented. Blood was collected and physical and neurologic exams were conducted on animals before and once per week during the trials. All animals were sacrificed and necropsies were performed on Day 29 of feeding, with the exception of one treated chicken that was sacrificed and necropsied on Day 15 of feeding. Microscopic lesions of vacuolar myelinopathy were present in the red-tailed hawk and five chickens that received a mixture of all tissues and two chickens that received only gastrointestinal tissues of coots with AVM lesions. Three of four treated chickens in the aquatic vegetation trial developed vacuolar lesions. None of four treatment pigs or any of the negative control animals developed vacuolar lesions. Chickens are susceptible to AVM and may serve as a useful animal model for future studies. Swine may be refractory to AVM or not affected by AVM at the same dose as are chickens and red-tailed hawks. The causative agent of AVM in affected coots is associated with the gastrointestinal tissues. Furthermore, AVM can be reproduced in chickens via ingestion of aquatic vegetation and associated materials collected from a lake during an AVM outbreak. The cause of AVM is most likely present in the materials associated with submerged vegetation because the vegetation itself (hydrilla) was the same at our AVM-positive and AVM-negative sites. PMID:15465715

  9. Theories of sexual orientation

    Microsoft Academic Search

    Michael D. Storms

    1980-01-01

    Various theories assume that sexual orientation is related to sex role orientation or to erotic orientation. Hypotheses derived from these 2 assumptions were tested. Heterosexual, bisexual, and homosexual undergraduates (185 Ss) were administered measures of their masculine and feminine attributes (determined by the Personal Attributes Questionnaire) and their erotic fantasies (measured by the Erotic Response and Orientation Scale). Results generally

  10. 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…

  11. Dating and Sexual Feelings

    MedlinePLUS

    ... unsafe. Sex you don’t agree to is rape, whether it’s with a stranger or a date. Rape includes forcing a body part or object into ... vagina, rectum (bottom), or mouth. Learn more about rape and sexual assault . If someone forces you to ...

  12. Rock and Sexuality.

    ERIC Educational Resources Information Center

    Frith, Simon; McRobbie, Angela

    1978-01-01

    Discusses rock as a form of both sexual expression and control. Describes rock's representations of masculinity and femininity and considers the contradictions involved in the representations. Relates the effects of rock to its form--as music, as commodity, as culture, and as entertainment. (JMF)

  13. Women and sexual problems

    MedlinePLUS

    ... If: You are distressed by a problem with sex Worried about your relationship Have pain or other symptoms with sex Call ... exam An interview to ask you about your relationships, current sexual ... sex, other medical problems you might have, medicines you ...

  14. Sexual Dysfunction in Women

    MedlinePLUS

    ... to 70% of couples have a problem with sex at some time in their relationships. Most women will have sex that doesn't feel good at some point ... that my problems will cause tension in my relationship. What should I do? Is it safe for me to have sex? Can I get pregnant? Source Female Sexual Dysfunction: ...

  15. Sexual function after strokes.

    PubMed

    Boller, François; Agrawal, Kunal; Romano, Alissa

    2015-01-01

    Strokes are the second leading cause of death and the third leading cause of disability worldwide. Thanks in part to better and more available diagnosis, treatment, and rehabilitation, the vast majority of stroke patients tend to survive strokes, particularly in the industrialized world. Motor disability and cognitive changes such as aphasia and visuospatial disorders are most often considered among the major contributors to stroke burden. This chapter discusses disorders of sexual functions as another frequent sequel of strokes. Strokes generally induce hyposexuality, but in some instances they may be followed by hypersexuality. There is some evidence suggesting that lesions of either hemisphere affect sexual activities, but for different reasons: aphasia and depression after left-hemisphere lesions, a deficit in arousal and perhaps visuospatial disorders after right-hemisphere lesions. Psychologic, psychosocial, and physical factors, as well as medications, play an important role. A better understanding of the psychosocial and physiologic mechanisms underlying sexual functioning can provide insight into improving sexual activity and therefore quality of life in patients affected by strokes and other brain lesions. PMID:26003250

  16. Fatal attraction: sexually cannibalistic invaders attract naive native mantids

    PubMed Central

    Fea, Murray P.; Stanley, Margaret C.; Holwell, Gregory I.

    2013-01-01

    Overlap in the form of sexual signals such as pheromones raises the possibility of reproductive interference by invasive species on similar, yet naive native species. Here, we test the potential for reproductive interference through heterospecific mate attraction and subsequent predation of males by females of a sexually cannibalistic invasive praying mantis. Miomantis caffra is invasive in New Zealand, where it is widely considered to be displacing the only native mantis species, Orthodera novaezealandiae, and yet mechanisms behind this displacement are unknown. We demonstrate that native males are more attracted to the chemical cues of introduced females than those of conspecific females. Heterospecific pairings also resulted in a high degree of mortality for native males. This provides evidence for a mechanism behind displacement that has until now been undetected and highlights the potential for reproductive interference to greatly influence the impact of an invasive species. PMID:24284560

  17. Fatal attraction: sexually cannibalistic invaders attract naive native mantids.

    PubMed

    Fea, Murray P; Stanley, Margaret C; Holwell, Gregory I

    2013-01-01

    Overlap in the form of sexual signals such as pheromones raises the possibility of reproductive interference by invasive species on similar, yet naive native species. Here, we test the potential for reproductive interference through heterospecific mate attraction and subsequent predation of males by females of a sexually cannibalistic invasive praying mantis. Miomantis caffra is invasive in New Zealand, where it is widely considered to be displacing the only native mantis species, Orthodera novaezealandiae, and yet mechanisms behind this displacement are unknown. We demonstrate that native males are more attracted to the chemical cues of introduced females than those of conspecific females. Heterospecific pairings also resulted in a high degree of mortality for native males. This provides evidence for a mechanism behind displacement that has until now been undetected and highlights the potential for reproductive interference to greatly influence the impact of an invasive species. PMID:24284560

  18. 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

  19. 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

  20. [Can we treat sexual addiction ?].

    PubMed

    Inescu Cismaru, A; Andrianne, R; Triffaux, F; Triffaux, J-M

    2013-01-01

    Sexual addiction or sexual dependence is characterized by hypersexuality, impaired regulation of sexual desire and sexual compulsivity, including having sex with uncontrolled excessive frequency (5 to 15 sexual acts per day for more than 6 months, from 15 years old). Between 3% and 6% of the adult population (> or =18 years) would have the characteristics of sexual addiction, disorder prevalent in the male population. The addictive processes affect three behavioral domains : motivation-reward, affect regulation and behavioral inhibition. Sex addiction is usually accompanied by other addictions, such as abuse of drugs or alcohol or sex toys that enhance sexual performance. Psychiatric comorbidities can be found : anxiety disorders, mood disorders. Several forms of treatment have been tried, using medication, cognitive-behavioral therapy and psychotherapy sessions alternated with exposure therapy in virtual reality. In this article, we will discuss the multiple definitions of hypersexuality and the possibilities of therapeutic approaches. PMID:23888589

  1. Sexual Identity as a Universal Process

    Microsoft Academic Search

    Frank R. Dillon; Roger L. Worthington; Bonnie Moradi

    \\u000a This chapter summarizes advances in current theoretical and empirical literature on sexual identity development. It proposes\\u000a a model of sexual identity that offers a more global (i.e., non-sexual identity group specific) perspective in comparison\\u000a to existing sexual identity group-specific sexual identity models. Attention to commonalities in sexual identity development\\u000a across sexual identity subgroups can offer a more global perspective that

  2. Hypersexuality: Psychopathology or normal variant of sexuality?

    Microsoft Academic Search

    Nicole J. Rinehart; Marita P. McCabe

    1997-01-01

    There is much controversy in the literature about what constitutes excessive sexual behavior and the extent to which the behavior can be considered a psychopathology. Historic and contemporary labels used to conceptualize excessive sexual behavior—e.g. nymphomania, satyriasis, sexual addiction, sexual dependency, sexual compulsivity and sexual impulsivity—are discussed. From the research literature is it not clear whether excessive sexual behavior is

  3. ORIGINAL PAPER Males, but not females, contribute to sexual isolation

    E-print Network

    Gabor, Caitlin - Department of Biology, Texas State University

    sexual isolation via conspecific mate preference between Gambusia affinis and G. geiseri in both sexes of Gambusia Celeste M. Espinedo · Caitlin R. Gabor · Andrea S. Aspbury Received: 6 May 2009 / Accepted: 2 reproductive isolation between the sexes in G. affinis and G. geiseri, but symmetrical species isolation

  4. Models of Speciation by Sexual Selection on Polygenic Traits

    Microsoft Academic Search

    Russell Lande

    1981-01-01

    The joint evolution of female mating preferences and secondary sexual characters of males is modeled for polygamous species in which males provide only genetic material to the next generation and females have many potential mates to choose among. Despite stabilizing natural selection on males, various types of mating preferences may create a runaway process in which the outcome of phenotypic

  5. 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...

  6. Sexual selection does not influence minisatellite mutation rate

    Microsoft Academic Search

    William Amos

    2009-01-01

    BACKGROUND: Moller and Cuervo report a significant trend between minisatellite mutation rate and the frequency of extra-pair copulations in birds. This is interpreted as evidence that the high rate of evolution demanded by sexual selection has itself selected for a higher mutation rate in species where selection is strongest. However, there are good a priori reasons for believing that their

  7. 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...

  8. Radiometric Measurements of the Microwave Emissivity of Reproducible Breaking Waves

    E-print Network

    Reising, Steven C.

    Radiometric Measurements of the Microwave Emissivity of Reproducible Breaking Waves Sharmila measurements of breaking waves on the open ocean showed that the emission due to wave breaking varies measurements on the open ocean. Therefore, the authors conducted a wave basin experiment in which reproducible

  9. Reproducibility of Interpreting "and" and "or" in Terminology Systems

    E-print Network

    Cimino, James J.

    Reproducibility of Interpreting "and" and "or" in Terminology Systems Eneida A. Mendonça, M.D.1 quality terminologies are a fundamental requirement in a range of health care applications. To ensure high quality terminologies we should reflect about the understandability, reproducibility and utility criteria

  10. Capacity of reproducing kernel spaces in learning theory

    Microsoft Academic Search

    Ding-xuan Zhou

    2003-01-01

    The capacity of reproducing kernel Hilbert spaces (RKHS) plays an essential role in the analysis of learning theory. Covering numbers and packing numbers of balls of these reproducing kernel spaces are important measurements of this capacity. We first present lower bound estimates for the packing numbers by means of nodal functions. Then we show that if a Mercer kernel is

  11. Parasites in sexual and asexual mollies (Poecilia, Poeciliidae, Teleostei): a case for the Red Queen?

    PubMed

    Tobler, Michael; Schlupp, Ingo

    2005-06-22

    The maintenance of sexual reproduction in the face of its supposed costs is a major paradox in evolutionary biology. The Red Queen hypothesis, which states that sex is an adaptation to fast-evolving parasites, is currently one of the most recognized explanations for the ubiquity of sex and predicts that asexual lineages should suffer from a higher parasite load if they coexist with closely related sexuals. We tested this prediction using four populations of the sexual fish species Poecilia latipinna and its asexual relative Poecilia formosa. Contrary to expectation, no differences in parasite load could be detected between the two species. PMID:17148156

  12. Parasites in sexual and asexual mollies (Poecilia, Poeciliidae, Teleostei): a case for the Red Queen?

    PubMed Central

    Tobler, Michael; Schlupp, Ingo

    2005-01-01

    The maintenance of sexual reproduction in the face of its supposed costs is a major paradox in evolutionary biology. The Red Queen hypothesis, which states that sex is an adaptation to fast-evolving parasites, is currently one of the most recognized explanations for the ubiquity of sex and predicts that asexual lineages should suffer from a higher parasite load if they coexist with closely related sexuals. We tested this prediction using four populations of the sexual fish species Poecilia latipinna and its asexual relative Poecilia formosa. Contrary to expectation, no differences in parasite load could be detected between the two species. PMID:17148156

  13. 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

  14. Policy on Gender-Based and Sexual Misconduct (50.4/70.2.4) Including Discrimination, Sexual Violence, Sexual Harassment,

    E-print Network

    Yang, Eui-Hyeok

    or expression, or affectional or sexual orientation. Stevens is further committed to maintaining a safe learning1 Policy on Gender-Based and Sexual Misconduct (50.4/70.2.4) Including Discrimination, Sexual Violence, Sexual Harassment, Relationship Violence, Stalking, and other forms of Gender-Based or Sexual

  15. Sexual Harassment Sexual harassment is the most common type of sexual violence. Surveys show that roughly 70% of

    E-print Network

    Machel, Hans

    Sexual Harassment Sexual harassment is the most common type of sexual violence. Surveys show that roughly 70% of women and 15% of men have experienced sexual harassment in the workplace.1 This number does not include sexual harassment that occurs in other environments such as learning institutions or social

  16. 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 Interpretation of the FSFI in Women with and without Hypoactive Sexual Desire Disorderjsm_1871 3096..3103 Eric P T Introduction. A validated cutpoint for the total Female Sexual Function Index scale score exists to classify

  17. A Revised Sexual Knowledge Assessment Tool for People with Intellectual Disabilities: Is Sexual Knowledge Related to Sexual Offending Behaviour?

    ERIC Educational Resources Information Center

    Talbot, T. J.; Langdon, Peter E.

    2006-01-01

    Background: The aim of the current study was to update an existing short measure of sexual knowledge and generate some initial reliability and normative data. Comparisons of sexual knowledge across several groups were made to examine whether or not a lack of sexual knowledge is related to sexual offending. Methods: The Bender Sexual Knowledge…

  18. Child Sexual Abuse, Peer Sexual Abuse, and Sexual Assault in Adulthood: A Multi-Risk Model of Revictimization

    Microsoft Academic Search

    Azmaira Hamid Maker; Markus Kemmelmeier; Christopher Peterson

    2001-01-01

    This study explored the predictors and consequences of sexual assault occurring after the age of 16 years in a nonclinical sample of women. Child sexual abuse occurring before the age of 16 years was the only predictor of later sexual assault among comorbid risk factors. Peer sexual abuse, number of perpetrators, age at time of sexual abuse, and severity of

  19. Sexual segregation in ungulates: a comparative test of three hypotheses.

    PubMed

    Ruckstuhl, K E; Neuhaus, P

    2002-02-01

    In most social ungulate species, males are larger than females and the sexes live in separate groups outside the breeding season. It is important for our understanding of the evolution of sociality to find out why sexual segregation is so widespread not only in ungulates but also in other mammals. Sexual body size dimorphism was proposed as a central factor in the evolution of sexual segregation in ungulates. We tested three hypotheses put forward to explain sexual segregation: the predation-risk, the forage-selection, and the activity budget hypothesis. We included in our analyses ungulate species ranging from non-dimorphic to extremely dimorphic in body size. We observed oryx, zebra, bighorn sheep and ibex in the field and relied on literature data for 31 additional species. The predation-risk hypothesis predicts that females will use relatively predator-safe habitats, while males are predicted to use habitats with higher predation risk but better food quality. Out of 24 studies on different species of ungulates, females and their offspring chose poorer quality but safer habitat in only eight cases. The forage-selection hypothesis predicts that females would select habitat based on food quality, while males should prefer high forage biomass. In fact, females selected higher quality food in only six out of 18 studies where males and females segregated, in eight studies there was no difference in forage quality and in four studies males were in better quality habitat. The activity budget hypothesis predicts that with increasing dimorphism in body size males and females will increasingly differ in the time spent in different activities. Differences in activity budgets would make it difficult for males and females to stay in mixed-sex groups due to increased costs of synchrony to maintain group cohesion. The predictions of the activity budget hypothesis were confirmed in most cases (22 out of 23 studies). The heavier males were compared to females, the more time females spent foraging compared to males. The bigger the dimorphism in body mass, the more males spent time walking compared to females. Lactating females spent more time foraging than did non-lactating females or males. Whether species were mainly bulk or intermediate feeders did not affect sexual differences in time spent foraging. We conclude that sexual differences in activity budgets are most likely driving sexual segregation and that sexual differences in predation risk or forage selection are additive factors. PMID:11911375

  20. 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

  1. 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

  2. 79 FR 77767 - Standards To Prevent, Detect, and Respond to Sexual Abuse and Sexual Harassment Involving...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2014-12-24

    ...to sexual abuse and sexual harassment, including notification, orientation, and instruction not...specifically about their sexual orientation or gender identity...information about their sexual orientation or gender...

  3. Dance and sexuality: many moves.

    PubMed

    Hanna, Judith Lynne

    2010-03-01

    This literature review of dance and sexual expression considers dance and religion, dance and sexuality as a source of power, manifestations of sexuality in Western theater art and social dance, plus ritual and non-Western social dance. Expressions of gender, sexual orientation, asexuality, ambiguity, and adult entertainment exotic dance are presented. Prominent concerns in the literature are the awareness, closeting, and denial of sexuality in dance; conflation of sexual expression and promiscuity of gender and sexuality, of nudity and sexuality, and of dancer intention and observer interpretation; and inspiration for infusing sexuality into dance. Numerous disciplines (American studies, anthropology, art history, comparative literature, criminology, cultural studies, communication, dance, drama, English, history, history of consciousness, journalism, law, performance studies, philosophy, planning, retail geography, psychology, social work, sociology, and theater arts) have explored dance and sexual expression, drawing upon the following concepts, which are not mutually exclusive: critical cultural theory, feminism, colonialism, Orientalism, postmodernism, poststructuralism, queer theory, and semiotics. Methods of inquiry include movement analysis, historical investigation, anthropological fieldwork, autoethnography, focus groups, surveys, and self-reflection or autobiographical narrative. Directions for future exploration are addressed. PMID:20358462

  4. 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

  5. THE SEXUAL PSYCHOPATH IN CALIFORNIA

    PubMed Central

    Rapaport, Walter; Lieberman, Daniel

    1956-01-01

    In California sexual offenders apprehended by the law are examined by court-appointed psychiatrists to determine whether they are “sexual psychopaths” as defined by California law and need treatment in a mental hospital. This paper outlines the criteria to be used as guides in properly selecting the persons for treatment. In general, sexual offenders fall into four categories. The first group consists of persons who cannot maintain proper control over their sexual impulses but whose acts do not constitute them a menace to the health and safety of others. They are not “sexual psychopaths” and their cases should be handled on their legal merits. The second group embraces persons who have committed a sexual offense on only one occasion and while under the influence of abnormal or unusual environmental stress. They are not considered “sexual psychopaths.” The third is made up of persons completely out of step with the social culture. They often have long criminal histories or long histories of social maladjustment. They are impulsive in their behavior and not remorseful of their misdeeds. Sexually deviant acts committed by such individuals are often incidental to their general asocial and amoral behavior. They do not suffer from inability to control sexual impulses. Their offenses should be judged according to the legal merits of the case. True “sexual psychopaths” have deviant menaceful sexual impulses and are not able to control them. The vast majority of these persons are those who have committed sexual offenses against children. The California State Department of Mental Hygiene has a maximum security hospital which is charged with the care and treatment of “sexual psychopaths.” PMID:13364662

  6. SEXUAL HARASSMENT UNIVERSITY OF MASSACHUSETTS AMHERST

    E-print Network

    Massachusetts at Amherst, University of

    SEXUAL HARASSMENT POLICY AND PROCEDURES UNIVERSITY OF MASSACHUSETTS AMHERST EQUAL OPPORTUNITY or studies without being sexually harassed. Sexual harassment of or by any member of the University community. For the purposes of this policy, it is defined as follows: Unwelcomed sexual advances, requests for sexual favors

  7. Sexual Arousal in Women with Superficial Dyspareunia

    Microsoft Academic Search

    Marieke Brauer; Ellen Laan; Moniek M. ter Kuile

    2006-01-01

    The role of sexual arousal in the etiology and\\/or maintenance of superficial dyspareunia is still unclear. Lack of sexual arousal may be both the cause and the result of anticipated pain. This study compared genital and subjective sexual responses to visual sexual stimuli of women with dyspareunia and women without sexual complaints. We investigated whether women with dyspareunia were less

  8. Sexual Information Seeking on Web Search Engines

    Microsoft Academic Search

    Amanda Spink; Andrew Koricich; B. J. Jansen; Charles Cole

    2004-01-01

    Sexual information seeking is an important element within human information behavior. Seeking sexually related information on the Internet takes many forms and channels, includ- ing chat rooms discussions, accessing Websites or searching Web search engines for sexual materials. The study of sexual Web queries provides insight into sexually-related information- seeking behavior, of value to Web users and providers alike. We

  9. Urban Heterosexual Couples’ Sexual Scripts for Three Shared Sexual Experiences

    Microsoft Academic Search

    David Wyatt Seal; Michael Smith; Brenda Coley; June Perry; Maria Gamez

    2008-01-01

    A heterogeneous sample of 38 young adult heterosexual couples living in a US city (N?=?76) provided narratives about their first, most physically arousing, and most emotionally intimate sexual experiences.\\u000a Physical arousal and passion and emotional intimacy intrapsychic scripts were evident across all three sexual experiences,\\u000a although both discourses encompassed multiple sub-themes. First sexual occasions generally adhered to more traditional interpersonal

  10. The Relationship Between Exposure to Sexual Music Videos and Young Adults' Sexual Attitudes

    Microsoft Academic Search

    Yuanyuan Zhang; Laura E. Miller; Kristen Harrison

    2008-01-01

    The purpose of this study was to examine the relationship between exposure to sexual music videos and young people's sexual attitudes (i.e., premarital sexual permissiveness and endorsement of the sexual double standard). Items gauging exposure to 75 music videos ranging in sexual explicitness were used to measure sexual video viewing among a sample of 266 undergraduate students. As expected, exposure

  11. What is sexual harassment? Harvard University has adopted the following definition of sexual

    E-print Network

    Chou, James

    What is sexual harassment? Harvard University has adopted the following definition of sexual harassment: Sexual harassment is any unwelcome conduct of a sexual nature, including unwelcome sexual advances, requests for favors, and other verbal, nonverbal, graphic, or physical conduct of a sexual nature

  12. Program in Human Sexuality Annual Report 2013 Program in Human Sexuality Annual Report 2013 3

    E-print Network

    Ciocan-Fontanine, Ionut

    Program in Human Sexuality Annual Report 2013 ADVANCING SEXUAL HEALTH #12;Program in Human Sexuality Annual Report 2013 3 At the Program in Human Sexuality, our mission is to advance the sexual service, and advocacy. Our vision is to revolutionize the sexual climate by eliminating barriers

  13. The Role of Attention in Sexual Arousal: Implications for Treatment of Sexual Dysfunction

    Microsoft Academic Search

    David C. de Jong

    2009-01-01

    The literature on the role of attention in sexual arousal is reviewed, especially that which has implications for noninvasive treatment of sexual dysfunction. Findings suggest that voluntary control of sexual arousal can be achieved through attentional focus on nonsexual cognitions or sexual fantasy. Cognitive biases may direct attention and thus facilitate or impede sexual arousal. Sexual arousal may be influenced

  14. [Public health and sexuality].

    PubMed

    Papart, Jean-pierre

    2014-03-19

    The paper questions the legitimacy and relevance of a potential emergence of any public health policies relating to sexology, as they exist for most of the major medical issues. It discusses the two major areas of intervention of sexology namely problems related to access to pleasure on the one hand, violence, abuse and other sexual perversions on the other hand. The legitimacy and relevance of public health policy to prevent the latter, i.e. sexual violence cannot be questioned. However, interventions to promote erotic skills are beyond the role and responsibility of the State but can be assigned to the civil society, especially community associations engaged in culture, solidarity and the promotion of social links in general. PMID:24734361

  15. Sexual aberration or instinctual vicissitude? Revisiting freud's "the sexual aberrations".

    PubMed

    Phillips, Sidney H

    2014-04-01

    The author reconsiders Freud's "The Sexual Aberrations," the first of his Three Essays on the Theory of Sexuality (1905), in light of contemporary psychoanalytic theory. Are the concepts of sexual aberration and norm still viable? The author argues that they are necessary but insufficient elements in current theory. He then presents a competing model in which sexuality can be reduced to a more elemental level of disturbance and wish, where it is an expression of a nonsexual wish--for example, to possess or control the object to eliminate separateness. The author presents clinical material to demonstrate this alternative model. PMID:24777366

  16. 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

  17. Measurement of Force Balance Repeatability and Reproducibility in the NTF

    NASA Technical Reports Server (NTRS)

    Hemsch, M. J.; Tuttle, D. G.; Houlden, H. P.; Graham, A. B.

    2004-01-01

    A recently published statistical approach for measuring and evaluating wind tunnel force balance repeatability and reproducibility is applied to three check standard tests in the National Transonic Facility at NASA Langley Research Center. Two different airframe models and force balances were used. The short-term repeatability and within-test reproducibility are separately estimated and correlations with tunnel parameters are carried out. Conjectures are presented for the development of scaling laws for predicting the repeatability and reproducibility of other force balance tests in the tunnel.

  18. Sexual assault in pregnancy.

    PubMed

    Satin, A J; Hemsell, D L; Stone, I C; Theriot, S; Wendel, G D

    1991-05-01

    Little is known about the acute effects of sexual assault on pregnant victims and the outcome of their gestations. A retrospective review of sexual assault victims in Dallas County from 1983-1988 revealed that 114 of 5734 (2%) were pregnant. There were 0.55 and 0.75 gravid sexual assault victims per 1000 deliveries for Dallas County and Parkland Memorial Hospital, respectively. The purposes of this study were to examine patient demographics, forensic evidence and patterns of injury in pregnant victims compared with 114 matched nonpregnant sexual assault victims, and to compare pregnancy outcome with that of the Parkland Memorial Hospital obstetric population. The typical victim was a black, parous gravida in her twenties at a mean gestational age of 15 weeks, without previous prenatal care. Vulvar (95%), oral (27%), and anal (6%) penetration were reported with similar frequency in both groups. The detection of whole and motile sperm from the vaginal specimens was similar in pregnant and nonpregnant women. Physical trauma was more common in nonpregnant victims (63 versus 43%; P less than .004), especially genital trauma (21 versus 5%; P less than .001). Injury was more common to the head and neck or extremities than to the abdomen, chest, or back in both groups. There was no difference in the pattern of trauma by gestational age, but there were no truncal injuries in women at 20 weeks' gestation or greater. There were no spontaneous abortions or deliveries within 4 weeks of the assault, but low birth weight delivery (24%) and preterm delivery (16%) were common.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2014084

  19. Sexually Transmitted Diseases

    Microsoft Academic Search

    Alice C. Thornton; Bojana Stevich; Janet N. Arno; Barbara Van Der Pol

    \\u000a Sexually transmitted diseases (STDs) affect an estimated 19 million people a year in the United States. Clinicians who may\\u000a encounter patients with STDs need to be aware of treatment guidelines and recent changes in treatment recommendations. For\\u000a example, due to increased resistance, fluoroquinolones are no longer recommended for the treatment of infections due to Neisseria gonorrhoeae. Recent new approaches also

  20. Female sexual dysfunction.

    PubMed

    Freedman, Murray A

    2002-01-01

    Happiness is an attitude, not an event! The glass is either half-full or half-empty; it simply depends on the viewer. Some rich people are miserable...some poor people are ecstatic. You cannot change the world but you can change yourself. You, and you alone, control your destiny. With very little practice, you can learn to think positively. Postmenopausal estrogen deficiency leads to urogenital atrophy. Sexual dysfunction and urinary dysfunction are the most inevitable but least publicized consequences of estrogen deficiency, and these represent important quality-of-life issues that patients and health care providers are often reluctant to discuss. In addition to estrogen deficiency, oophorectomized women may be subject to androgen deficiency and problems with libido. While the relationship with one's partner is the quintessential factor in female sexuality, hormone deficiency remains important, especially in reference to genital atrophy. Humans are the products of learned behavior. We literally become what we think. "I am sick and tired" becomes a self-fulfilling prophecy. Self-esteem represents learned behavior just as ego does...but there is a world of difference between the two. Sexuality is enhanced by good self-esteem and hindered by ego: two partners working together can reach far greater heights than either alone ever imagined...one and one can equal three! There are good data to substantiate that happy people have more sex and that people who have more sex are happier. Partners need to learn to honor one another, communicate in a positive manner, develop touching salutations, be a spouse at home, and make their bedroom a sacred sanctuary. With a little behavior modification and hormone therapy, sexuality can remain a priority ad infinitum. PMID:11900270

  1. SEXUALLY TRANSMITTED INFECTIONS

    NSDL National Science Digital Library

    Ms. Schultz

    2010-10-27

    Find links to various topics below: CDC = Center for Disease Control and Prevention CDC- A-Z Index CDC- Diesease and Conditions writeInsertLink('projectBody','CDC- Diesease and Conditions'); CDC - HIV/AIDS STDs CDC - HIV Basic Information CDC - HIV - LInks to other resources CDC - STD Picture Cards Herpes-Coldsores Kids Health MedlinePlus - Sexually Transmitted Diseases Teen Health Wellness real life real answers ...

  2. Sexuality education in Brazil.

    PubMed

    Suplicy, M

    1994-01-01

    The development of a comprehensive program of sex education in Brazilian schools is described in the context of Brazil's culture and traditions such as the Carnival. The influence of Catholicism is explored as is the effect of the behavioral restrictions called for by scientists concerned about sexually transmitted diseases. The Brazilian response to homosexuality is described, and the emergence of a public discussion of sexuality in the media is traced. It is noted that improvements in the status of women have been held in check by a public ridicule of feminism and by the strength of the traditional patriarchal structures which dominate the culture. With this picture given of how the issue of sexuality fits into Brazilian life, the 1980s initiative on the part of the Work and Research Group for Sex Education is described. Opposition to this effort has largely taken the form of passive resistance; even the Catholic Church has not officially protested the sex education program. Details are provided about 1) the selection of teachers, teacher training, and weekly supervisory teacher meetings; 2) the way in which parental permission for student participation was gained; 3) the implementation of the program; 4) the successes achieved; and 5) the difficulties encountered. Finally, it is noted that plans were made to expand the sex education project from the Sao Paulo area to 6 additional large cities in 1994. Also planned is the publication of the Brazilian Guidelines for Comprehensive Sexuality which will explain the sex education methodology and be extremely valuable in the establishment of new projects. PMID:12287356

  3. 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

  4. The effects of autobiographic sexual memory recall on the sexual response of sexually functional men.

    PubMed

    van Lankveld, Jacques; Martin, Alec; Hubben, Dave; Creutz, Nikky; Verboon, Peter

    2013-08-01

    In this experimental study, we investigated how recalling positive, negative, and affectively neutral autobiographic sexual experiences in their personal history affected the current sexual response of sexually functional male volunteers. Based on an attentional-capacity account of sexual arousal, we predicted that affectively charged autobiographic sexual memory recall, both with negative and positive valence, would negatively impact genital arousal, compared to recalling affectively neutral sexual experiences. We expected that subjective sexual arousal would not be differentially affected by emotional memory valence. We measured subjective and genital response to erotic video fragments in sexually functional volunteers (N = 24) in a within-subjects, repeated-measures design. For the memory manipulation, participants received instructions to visualize and mentally re-experience positive, negative, and neutral sexual episodes from autobiographic memory. Memory instructions were found to result in the expected affective states. As predicted, compared to recalling neutral memory, mean genital response was significantly lower during recalling positive and negative memory. However, contrary to prediction, subjective sexual arousal was affected, when multilevel analysis was performed, including a time effect. The implications of the findings were discussed with respect to the advancement of theory and therapeutic intervention. PMID:23519590

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

    PubMed Central

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

    2012-01-01

    Objective To assess the degree to which a history of 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 self-report questionnaires at intake including the Sexual Satisfaction Scale for Women (SSS-W), the Female Sexual Function Index (FSFI), and the Trauma History Questionnaire (THQ). Results Desire, arousal, lubrication, and orgasm interacted with sexual abuse status in predicting sexual distress such that sexual functioning was more weakly associated with distress for women with a history of CSA. This disconnect was more pronounced for women who were abused by a family member. Conclusion CSA status serves as an important moderator of the association between sexual functioning and sexual distress in women. Specifically, women with a history of CSA show higher levels of distress in the context of good sexual functioning as compared to women without a history of CSA. Possible explanations and clinical implications are discussed. PMID:22391416

  6. [Sexual dysfunctions in selected endocrinopathies].

    PubMed

    Skrzypulec, Violetta; Nowosielski, Krzysztof; Drosdzol, Agnieszka; Kowalaczyk, Robert

    2005-01-01

    According to the socio-sexological reports approximately 40-45% of women and up to 30% of males may suffer from different sexual dysfunctions. The prevalence of those disorders is gradually increasing with age. Multiply numbers of endocrinopathies may influence the human sexual life. In diabetic patients all phases of the sexual responses cycle, especially orgasm, might be affected. Women diagnosed with PCOS have decreased adaptation to the sexual life, low self-esteem and perception of self sexual attractiveness. The intimacy of infertile couples has not been well described and the characteristic of particular dysfunction in sex life has not been established yet. Interdisciplinary approach, understood as treatment of the endocrinopathy accompanied with psychological and sexological counseling, seems to be the fundamental issue in the therapy of sexual dysfunctions in patients with endocrinological disorders. PMID:16821220

  7. 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

  8. Sexual Victimization, Alcohol Intoxication, Sexual-Emotional Responding, and Sexual Risk in Heavy Episodic Drinking Women

    PubMed Central

    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.

    2013-01-01

    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

  9. RT-qPCR reveals opsin gene upregulation associated with age and sex in guppies (Poecilia reticulata) - a species with color-based sexual selection and 11 visual-opsin genes

    PubMed Central

    2011-01-01

    Background PCR-based surveys have shown that guppies (Poecilia reticulata) have an unusually large visual-opsin gene repertoire. This has led to speculation that opsin duplication and divergence has enhanced the evolution of elaborate male coloration because it improves spectral sensitivity and/or discrimination in females. However, this conjecture on evolutionary connections between opsin repertoire, vision, mate choice, and male coloration was generated with little data on gene expression. Here, we used RT-qPCR to survey visual-opsin gene expression in the eyes of males, females, and juveniles in order to further understand color-based sexual selection from the perspective of the visual system. Results Juvenile and adult (male and female) guppies express 10 visual opsins at varying levels in the eye. Two opsin genes in juveniles, SWS2B and RH2-2, accounted for >85% of all visual-opsin transcripts in the eye, excluding RH1. This relative abundance (RA) value dropped to about 65% in adults, as LWS-A180 expression increased from approximately 3% to 20% RA. The juvenile-to-female transition also showed LWS-S180 upregulation from about 1.5% to 7% RA. Finally, we found that expression in guppies' SWS2-LWS gene cluster is negatively correlated with distance from a candidate locus control region (LCR). Conclusions Selective pressures influencing visual-opsin gene expression appear to differ among age and sex. LWS upregulation in females is implicated in augmenting spectral discrimination of male coloration and courtship displays. In males, enhanced discrimination of carotenoid-rich food and possibly rival males are strong candidate selective pressures driving LWS upregulation. These developmental changes in expression suggest that adults possess better wavelength discrimination than juveniles. Opsin expression within the SWS2-LWS gene cluster appears to be regulated, in part, by a common LCR. Finally, by comparing our RT-qPCR data to MSP data, we were able to propose the first opsin-to-?max assignments for all photoreceptor types in the cone mosaic. PMID:21447186

  10. Effect of Sexual Debut on Vaginal Microbiota in a Cohort of Young Women

    PubMed Central

    Mitchell, Caroline M.; Fredricks, David N.; Winer, Rachel L.; Koutsky, Laura

    2012-01-01

    Background Bacterial vaginosis is uncommon in women who are virgins. We estimated effects of sexual debut on vaginal bacterial colonization. Methods Women who were virgins and aged 18–22 enrolled in a study of human papillomavirus acquisition were followed every 4 months for up to 2 years. Vaginal swabs from before and after sexual debut, or two independent visits for those remaining virginal were tested by quantitative polymerase chain reaction for Lactobacillus crispatus, L. jensenii, L. iners, Gardnerella vaginalis, and the bacterial vaginosis-associated species Atopobium vaginae, Megasphaera spp., Leptotrichia spp, Sneathia, spp BVAB1, BVAB2, and BVAB3. Results We evaluated 97 women: 71 who became sexually active and 26 who remained virginal. At first sampling, 22/26 (85%) of women who remained virginal were colonized with Lactobacillus species compared to 22/26 (85%) at follow-up (p > 0.99). G. vaginalis was present in 12/26 (46%) initially, and 11/26 (42%) at follow-up (p > 0.99). Among women who became sexually active, colonization with Lactobacillus species remained stable: 65/71 (92%) vs. 66/71 (93%) (p > 0.99), while colonization with G. vaginalis increased [28/71 (39%) vs 40/71 (56%); p = 0.02]. Among women who did not initiate sexual activity during the study, 2/26 (8%) had any bacterial vaginosis-associated species detected at both the first and second visits(p > 0.99). Among women who became sexually active during the study 15/71 (21%) were colonized with bacterial vaginosis-associated species initially, compared to 13/71 (18%) after sexual debut (p = 0.77). Conclusions Among women who were virgins, vaginal colonization with bacterial vaginosis-associated bacterial species is uncommon and does not change after sexual debut. PMID:23168754

  11. Vaginal microbiome and sexually transmitted infections: an epidemiologic perspective

    PubMed Central

    Brotman, Rebecca M.

    2011-01-01

    Vaginal bacterial communities are thought to help prevent sexually transmitted infections. Bacterial vaginosis (BV) is a common clinical syndrome in which the protective lactic acid–producing bacteria (mainly species of the Lactobacillus genus) are supplanted by a diverse array of anaerobic bacteria. Epidemiologically, BV has been shown to be an independent risk factor for adverse outcomes including preterm birth, development of pelvic inflammatory disease, and acquisition of sexually transmitted infections. Longitudinal studies of the vaginal microbiome using molecular techniques such as 16S ribosomal DNA analysis may lead to interventions that shift the vaginal microbiota toward more protective states. PMID:22133886

  12. 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.

  13. Sexual sterilization of the daggerblade grass shrimp Palaemonetes pugio (Decapoda: Palaemonidae) by the bopyrid isopod Probopyrus pandalicola (Isopoda: Bopyridae).

    PubMed

    Sherman, Michele B; Curran, Mary Carla

    2015-02-01

    Probopyrus pandalicola is a bopyrid isopod that infects several palaemonid shrimp species, including the daggerblade grass shrimp Palaemonetes pugio . The parasite can have several negative effects on its host, including loss of hemolymph, reduced reproductive potential, and decreased molting frequency and growth. To date, there are conflicting reports on whether Probopyrus pandalicola affects the reproductive capability of both male and female daggerblade grass shrimp. The purpose of this study was to determine whether infection by Probopyrus pandalicola resulted in the sexual sterilization of Palaemonetes pugio , and if the reproductive capability of male and/or female shrimp was restored after the bopyrid was removed. We found that parasitized and deparasitized males were able to fertilize the eggs of unparasitized females successfully, as 18.9 ± 7.1% and 42.7 ± 5.2% of the females paired with them became ovigerous in 4 wk, respectively. Neither parasitized nor deparasitized females became ovigerous when placed with unparasitized males during the 4-wk period. However, 45.4 ± 20.6% of deparasitized females did become ovigerous within 10 wk. Despite the fact that female shrimp are able to reproduce again when no longer parasitized, the majority of females remain infected with the bopyrid for their entire lives. Therefore, the sexual sterilization of female shrimp could potentially have a significant impact on estuarine food webs, as grass shrimp are conduits of detrital energy and a food source for many recreationally and commercially important species in estuaries on the East Coast of the United States and in the Gulf of Mexico. PMID:25353615

  14. Men's sexual self-schema

    Microsoft Academic Search

    Barbara L. Andersen; Jill M. Cyranowski; Derek Espindle

    1999-01-01

    Sexual self-schemas are cognitive generalizations about sexual aspects of oneself. In Part 1, a measure of men's sexual self-schema is developed. Studies of test—retest and internal consistency reliability and validity studies of factor analysis, internal structure, convergent and discriminant validity, process, group difference, and change are provided. The construct consists of 3 dimensions: passionate—loving, powerful-aggressive, and open-minded-liberal traits. In Part

  15. 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

  16. Biology and Sexual Minority Status

    Microsoft Academic Search

    William Byne

    The purpose of this chapter is to provide clinicians with an overview of current knowledge pertaining to the biology of sexual\\u000a minority status. Under the umbrella of sexual minority are included homosexuals, bisexuals, transgenders and intersexes. The\\u000a most developed biologic theory pertaining to sexual minority status is the prenatal hormonal\\u000a hypothesis. According to this hypothesis, prenatal hormones act (primarily during

  17. Functional inverse regression and reproducing kernel Hilbert space 

    E-print Network

    Ren, Haobo

    2006-10-30

    data from a Reproducing Kernel Hilbert Space (RKHS) prospective is developed. We proposed a functional multiple-index model which models a real response variable as a function of a few predictor variables called indices. These indices are random...

  18. Reproducible isolation of distinct, overlapping segments of the phosphoproteome

    E-print Network

    Cai, Long

    Reproducible isolation of distinct, overlapping segments of the phosphoproteome Bernd Bodenmiller1 detect different, partially overlapping segments of the phosphoproteome and that, at present, no single method is sufficient for a comprehensive phosphoproteome analysis. Among the several hundred known

  19. 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

  20. A Reproducible Technique for Arthroscopic Acromioclavicular Joint Excision.

    PubMed

    Wheelton, Andrew; Kenyon, Peter; Ravenscroft, Matt

    2015-06-01

    Arthroscopic acromioclavicular joint excision is a commonly performed but technically demanding procedure. Incomplete excision can leave residual symptoms. We present a simple, reproducible technique ensuring satisfactory excision of the joint. PMID:26078510

  1. Properties of galaxies reproduced by a hydrodynamic simulation

    E-print Network

    Genel, S.

    Previous simulations of the growth of cosmic structures have broadly reproduced the ‘cosmic web’ of galaxies that we see in the Universe, but failed to create a mixed population of elliptical and spiral galaxies, because ...

  2. 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

  3. 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

  4. 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 ...

  5. Sexual Assault Awareness Month April 4, 2014

    E-print Network

    Hill, Wendell T.

    Sexual Assault Awareness Month April 4, 2014 Dear University of Maryland community: I would like to thank the Sexual Harassment Policies of the Office on Sexual Misconduct and Title IX Compliance. Please join me

  6. 18 CFR 1300.104 - Sexual harassment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    It is TVA policy that all TVA employees are responsible for assuring that the workplace is free from sexual harassment. Accordingly, all employees must avoid any action or conduct which could be viewed as sexual harassment including: (a) Unwelcome sexual...

  7. Premarital Sexual Behavior, Attitudes, and Emotional Adjustment

    ERIC Educational Resources Information Center

    Diamant, Louis

    1970-01-01

    No relationship was found between adjustment and premarital sexual intercourse for either male or female subjects. Low permissiveness scores (Attitude Scales on Sexual Permissiveness and Sexual Behavior Questionnaires) were related to maladjustment in males. (DB)

  8. Extramarital Sexual Permissiveness: Conditions and Contingencies

    ERIC Educational Resources Information Center

    Singh, B. Krishna; And Others

    1976-01-01

    This paper examines the relationship of some social factors with extramarital sexual permissiveness. Findings indicate that the best variable to explain extramarital sexual permissiveness is premarital sexual permissiveness. (Author)

  9. Comparison of reproducing and nonreproducing starprobe strategies for galactic exploration

    Microsoft Academic Search

    F. Valdes; R. A. Freitas Jr.

    1980-01-01

    Reproducing and nonreproducing strategies for missions of interstellar and galactic discovery are compared. Self-reproducing probes are found to be the method of choice for active exploration programs lasting more than 10,000 years, involving searches of more than 1 million target stars to distances greater than 1000 light years in the Galactic Disk, and are superior to one-shot 'Bracewell probes' for

  10. Determinants of Sexual Network Structure and Their Impact on Cumulative Network Measures

    PubMed Central

    Schmid, Boris V.; Kretzschmar, Mirjam

    2012-01-01

    There are four major quantities that are measured in sexual behavior surveys that are thought to be especially relevant for the performance of sexual network models in terms of disease transmission. These are (i) the cumulative distribution of lifetime number of partners, (ii) the distribution of partnership durations, (iii) the distribution of gap lengths between partnerships, and (iv) the number of recent partners. Fitting a network model to these quantities as measured in sexual behavior surveys is expected to result in a good description of Chlamydia trachomatis transmission in terms of the heterogeneity of the distribution of infection in the population. Here we present a simulation model of a sexual contact network, in which we explored the role of behavioral heterogeneity of simulated individuals on the ability of the model to reproduce population-level sexual survey data from the Netherlands and UK. We find that a high level of heterogeneity in the ability of individuals to acquire and maintain (additional) partners strongly facilitates the ability of the model to accurately simulate the powerlaw-like distribution of the lifetime number of partners, and the age at which these partnerships were accumulated, as surveyed in actual sexual contact networks. Other sexual network features, such as the gap length between partnerships and the partnership duration, could–at the current level of detail of sexual survey data against which they were compared–be accurately modeled by a constant value (for transitional concurrency) and by exponential distributions (for partnership duration). Furthermore, we observe that epidemiological measures on disease prevalence in survey data can be used as a powerful tool for building accurate sexual contact networks, as these measures provide information on the level of mixing between individuals of different levels of sexual activity in the population, a parameter that is hard to acquire through surveying individuals. PMID:22570594

  11. Sexual Selection & Mating I. Sexual selection overview

    E-print Network

    Dever, Jennifer A.

    fitness for the offspring. 3) Sensory bias or sensory drive some aspect of the sensory world biases females to · eg, if the species feeds on red prey, their visual system may be tuned to red wavelengths #12 Ratio often Skewed: #12;5 Rana sylvatica Bufo bufo, Scaphiopus B. Mate Guarding Behavior If searching

  12. Males in the shade: habitat use and sexual segregation in the Galápagos sea lion ( Zalophus californianus wollebaeki )

    Microsoft Academic Search

    Jochen B. W. Wolf; Göran Kauermann; Fritz Trillmich

    2005-01-01

    In many sexually dimorphic species adult sexes tend to segregate socially, spatially, or in habitat use. Several hypotheses have been formulated regarding underlying mechanisms. We investigated terrestrial habitat use and sexual segregation in a tropical otariid, the Galápagos sea lion (Zalophus californianus wollebaeki), where most of the hypotheses can be ruled out a priori. Factors relating to thermoregulation and costs

  13. Sexually Transmitted Infections and Sexual Dysfunctions among Newly Returned Veterans with and without Military Sexual Trauma

    Microsoft Academic Search

    Jessica A. Turchik; Joanne Pavao; Deborah Nazarian; Samina Iqbal; Caitlin McLean; Rachel E. Kimerling

    2012-01-01

    This cross-sectional study examined the odds of being diagnosed with a sexually transmitted infection (STI) or a sexual dysfunction disorder (SDD) among Operation Enduring Freedom\\/Operation Iraqi Freedom (OEF\\/OIF) American veterans receiving care in the Veterans Health Administration (VHA) in relation to whether or not they have experienced military sexual trauma (MST). Among those veterans who experienced MST, the influence of

  14. 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…

  15. Adolescent Sexuality Related Beliefs and Differences by Sexual Experience Status

    ERIC Educational Resources Information Center

    Tolma, Eleni L.; Oman, Roy F.; Vesely, Sara K.; Aspy, Cheryl B.; Rodine, Sharon; Marshall, LaDonna; Fluhr, Janene

    2007-01-01

    Purpose: To examine if attitudes toward premarital sex, beliefs about peer influence, and family communication about sexual relationships differ by sexual experience status. Methods: Data were collected from a randomly selected ethnically diverse youth sample (N = 1,318) residing in two Midwestern cities. The primary method used in data analysis…

  16. Discourses of Exclusion: Sexuality Education's Silencing of Sexual Others

    Microsoft Academic Search

    John P. Elia; Mickey Eliason

    2010-01-01

    This article begins with a broad historical overview detailing how school-based sexuality education has been taught from a specific kind of heterosexual perspective that has excluded lesbian, gay, bisexual, transgender, and queer-identified (LGBTQ) students as well as heterosexual students who do not fall along culturally dominant heterosexual lines. To illustrate such exclusionary sexuality education, we examine the discourses of exclusion

  17. Male Sexuality and Couple Sexual Health: A Case Illustration

    Microsoft Academic Search

    Michael E. Metz; Barry W. McCarthy

    2010-01-01

    Male sexual problems are common and offer exceptional opportunities for clinicians to not only relieve distress but enhance individual and relationship satisfaction. However, limited clinical focus on sex behaviors alone often overlook this opportunity. With more comprehensive approaches, clinicians are able to both facilitate improved sexual function and to promote positive, realistic principles for healthy and satisfying male and couple

  18. Self-Reported Sexual Identity, Sexual Behaviors and Health Risks

    Microsoft Academic Search

    Susan Scheer; Cheryl A. Parks; Willi McFarland; Kimberly Page-Shafer; Viva Delgado; Juan D. Ruiz; Fred Molitor; Jeffrey D. Klausner

    2002-01-01

    Data from a population-based survey of low-income young women (n = 2,438) was used to examine substance use patterns and exposure to coerced sexual activity among women who self-identify as lesbian (n = 34) or bisexual (n = 91), or who report sexual behavior exclusively with other women (n = 17) or with both women and men (n = 189).

  19. 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…

  20. Elevated sexual activity in violent marriages: Hypersexuality or sexual extortion?

    Microsoft Academic Search

    Alfred DeMaris

    1997-01-01

    Couples have been observed to be more sexually active in marriages characterized by violence. Two alternative hypotheses are posed to account for this. The hypersexuality hypothesis is that a pre?existing propensity for both aggression and violence characterizes both partners in selected marriages. The sexual extortion hypothesis is that male violence creates a climate of fear in which women are coerced

  1. Sexual Assault Prevention Programs and Survivor Support Services

    E-print Network

    Escher, Christine

    Sexual Assault Prevention Programs and Survivor Support Services The Sexual Violence Prevention education on a wide range of sexual violence related issues, such as bystander behavior, stalking, interpersonal violence and sexual assault. The Sexual Violence Prevention and Education Coordinator serves

  2. Sexual narcissism and infidelity in early marriage.

    PubMed

    McNulty, James K; Widman, Laura

    2014-10-01

    There is theoretical reason to believe that narcissism is associated with infidelity. Yet, studies that have examined this association have yielded inconsistent results. Given that these inconsistencies may have emerged because prior studies used global assessments of narcissism that do not capture the extent to which the components of narcissism are activated in the sexual domain, the current research drew from two longitudinal studies of 123 married couples to examine the extent to which sexual narcissism predicted marital infidelity. Consistent with the idea that narcissism predicts sexual behavior when activated in the sexual domain, own sexual narcissism was positively associated with infidelity, controlling for own marital and sexual satisfaction, own globally-assessed narcissism, partner globally-assessed narcissism, and partner sexual narcissism. Helping to explain why this association emerged, further analyses demonstrated that it was driven by all four facets of sexual narcissism-sexual exploitation, grandiose sense of sexual skill, sexual entitlement (Study 1 only), and lack of sexual empathy (husbands only). Additionally, although partner sexual narcissism was unrelated to infidelity on average, partners' grandiose sense of sexual skill and partners' sexual entitlement (Study 2 only) were positively associated with infidelity, and partners' lack of sexual empathy was negatively associated with infidelity (Study 2 only). These findings highlight the benefits of using domain-specific measures of sexual narcissism in research on sexual behavior and the benefits of using domain-specific measures of personality more generally. PMID:24696386

  3. Predictors of sexual assertiveness: the role of sexual desire, arousal, attitudes, and partner abuse.

    PubMed

    Santos-Iglesias, Pablo; Sierra, Juan Carlos; Vallejo-Medina, Pablo

    2013-08-01

    This study was conducted to test interpersonal, attitudinal, and sexual predictors of sexual assertiveness in a Spanish sample of 1,619 men and 1,755 women aged 18-87 years. Participants completed measures of sexual assertiveness, solitary and dyadic sexual desire, sexual arousal, erectile function, sexual attitudes, and frequency of partner abuse. In men, higher sexual assertiveness was predicted by less non-physical abuse, more positive attitudes toward sexual fantasies and erotophilia, higher dyadic desire, and higher sexual arousal. In women, higher sexual assertiveness was predicted by less non-physical abuse, less solitary sexual desire and higher dyadic sexual desire, arousal, erotophilia, and positive attitudes towards sexual fantasies. Results were discussed in the light of prevention and educational programs that include training in sexual assertiveness skills. PMID:22875718

  4. Insulin Signaling Mediates Sexual Attractiveness in Drosophila

    PubMed Central

    Hansen, Ingrid; Dreisewerd, Klaus; Dierick, Herman A.; Yew, Joanne Y.; Pletcher, Scott D.

    2012-01-01

    Sexually attractive characteristics are often thought to reflect an individual's condition or reproductive potential, but the underlying molecular mechanisms through which they do so are generally unknown. Insulin/insulin-like growth factor signaling (IIS) is known to modulate aging, reproduction, and stress resistance in several species and to contribute to variability of these traits in natural populations. Here we show that IIS determines sexual attractiveness in Drosophila through transcriptional regulation of genes involved in the production of cuticular hydrocarbons (CHC), many of which function as pheromones. Using traditional gas chromatography/mass spectrometry (GC/MS) together with newly introduced laser desorption/ionization orthogonal time-of-flight mass spectrometry (LDI-MS) we establish that CHC profiles are significantly affected by genetic manipulations that target IIS. Manipulations that reduce IIS also reduce attractiveness, while females with increased IIS are significantly more attractive than wild-type animals. IIS effects on attractiveness are mediated by changes in CHC profiles. Insulin signaling influences CHC through pathways that are likely independent of dFOXO and that may involve the nutrient-sensing Target of Rapamycin (TOR) pathway. These results suggest that the activity of conserved molecular regulators of longevity and reproductive output may manifest in different species as external characteristics that are perceived as honest indicators of fitness potential. PMID:22570625

  5. Cortisol, Sexual Arousal, and Affect in Response to Sexual Stimuli

    PubMed Central

    Hamilton, Lisa Dawn; Rellini, Alessandra H.; Meston, Cindy M.

    2008-01-01

    Introduction Theoretically, the physiological response to stress should inhibit the sexual response. This has been demonstrated experimentally in animal models, and correlationally in studies of human reproduction. It is reasonable to expect, then, that the stress response would be blunted during sexual arousal, and several researchers have found a pattern of decreasing cortisol during sexual arousal. Aim In the present study, we explored individual differences in women’s cortisol response to sexual arousal in a laboratory setting. We also examined how cortisol response in the laboratory related to a validated measure of sexual arousal functioning in real life. Main Outcome Measures Cortisol levels were measured in saliva via enzyme immunoassay. Subjective arousal was measured by a self-report questionnaire, and genital arousal was measured by a vaginal photoplethysmograph. Methods Subjective and physiological responses to an erotic film were assessed in 30 women. Saliva samples were taken at baseline and following the film. Results The majority of women (N = 20) showed a decrease in cortisol; nine women showed an increase in response to an erotic film. The women who showed an increase in cortisol had lower scores on the Arousal, Desire, and Satisfaction domains of the Female Sexual Function Index. Genital arousal in the laboratory was not related to cortisol change. Conclusions Women who show an increase in cortisol in response to sexual stimuli in the laboratory have lower levels of functioning in certain areas of their sexual life compared with women who show a decrease in cortisol. Stress related to sexual performance may interfere with sexual arousal. PMID:18624961

  6. The role of sexual self-schema in a diathesis—stress model of sexual dysfunction

    Microsoft Academic Search

    Susan L. Aarestad; Barbara L. Andersen

    1999-01-01

    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

  7. 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

  8. 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...

  9. Clackamas Adolescent Sexual Offender Intervention.

    ERIC Educational Resources Information Center

    King, Richard B.

    The Clackamas Adolescent Sexual Offender Intervention program is designed to interrupt and change behavior of clients who are juvenile sexual offenders at risk to re-offend. Intervention is scheduled for each offender over a 52-week period with groups meeting each week for 2 hours, and an all day session each 6-week period on Saturday. The…

  10. Evolutionary perspectives on sexual offending

    Microsoft Academic Search

    Vernon L. Quinsey; Martin L. Lalumière

    1995-01-01

    Evolutionary psychology has been successful in explaining diverse phenomena, such as the relative rarity with which people commit crimes against their biological relatives and the observed differences between males and females in romantic and sexual interest. According to an evolutionary view, the current sexual motivations of males and females were created in ancestral environments through their relationship with reproductive success.

  11. 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…

  12. Sexual Orientation and Professional Dance

    Microsoft Academic Search

    J. Michael Bailey; Michael Oberschneider

    1997-01-01

    The stereotypical professional male dancer is a gay man. However, little if any systematic research has investigated the validity of this stereotype, much less the reasons why male sexual orientation would be associated with interest in dance. We interviewed 136 professional dancers about the prevalence of homosexuality among dancers, the dancers' own sexual development, and relationships between dancers of different

  13. AIDS Stigma and Sexual Prejudice

    Microsoft Academic Search

    GREGORY M. HEREK; JOHN P. CAPITANIO

    1999-01-01

    This article presents national survey data to assess the extent to which AIDS-related stigma remains linked to public attitudes toward homosexuality in the United States. Most heterosexuals continue to associate AIDS primarily with homosexuality or bisexuality, and this association is correlated with higher levels of sexual prejudice (antigay attitudes). Although all people who contract AIDS sexually are assigned blame for

  14. 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…

  15. 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)

  16. 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…

  17. The brief sexual attitudes scale.

    PubMed

    Hendrick, Clyde; Hendrick, Susan S; Reich, Darcy A

    2006-02-01

    The measurement of sexual attitudes is important, and ease of scale usability is one key aspect of measurement. This paper details three studies conducted to develop a briefer and thus more efficient version of the multidimensional Sexual Attitudes Scale (43 items). The first two studies (I and II) employed existing data sets to develop a 23-item version of the Sexual Attitudes Scale, using exploratory factor analysis in Study I and confirmatory factor analysis in Study II. The same four subscales of Permissiveness, Birth Control (formerly called Sexual Practices), Communion, and Instrumentality were retained in the 23-item measure, called the Brief Sexual Attitudes Scale. Study III was a prospective data collection using only the 23 items composing the Brief Sexual Attitudes Scale. The four subscales were hypothesized to correlate with a number of relationship measures in predictable ways. Results indicated that the Brief Sexual Attitudes Scale is a reliable and valid measure of the four sexual attitudes, and has strong psychometric properties. It should be effective and efficient for both research and clinical uses. PMID:16817070

  18. College Students' Attitudes toward Sexuality.

    ERIC Educational Resources Information Center

    Medina, Marianna K.

    This study was conducted to investigate the sexual attitudes of college students (N=384) at a Western Kansas university. Students completed the Sexual Attitudes Scale, the Personal Attribute Inventory, and a demographic questionnaire examining gender, birth order, family structure, and age at which one started dating. Of 20 main effects…

  19. Sexual Attitudes of College Students.

    ERIC Educational Resources Information Center

    Etchison, Marilyn G.

    This study investigated the sexual attitudes of college students at a western Kansas university. The independent variables employed were gender, family structure, family sex communication, age, and classification. The dependent variables were the following subscales of sexual attitudes: permissiveness, sex practices, communion, and…

  20. About Sexually Transmitted Diseases (STDs)

    MedlinePLUS

    KidsHealth > Teens > Sexual Health > STDs & Other Infections > About Sexually Transmitted Diseases (STDs) Print A A A Text Size What's in this ... of all ages and backgrounds who are having sex — it doesn't matter if they're rich or ... have become common among teens. Because teens are more at risk for getting ...