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Sample records for pili sex

  1. Ultraviolet irradiation disrupts somatic pili structure and function

    Energy Technology Data Exchange (ETDEWEB)

    Silverblatt, F.J.

    1979-09-01

    Three piliated bacterial species were exposed to ultraviolet light and the effect of increasing duration of irradiation on the integrity of the somatic pili was quantitated by negative-stain electron microscopy. Heavily piliated Proteus mirabilis became devoid of pili after 20 min of irradiation, but Escherichia coli and Neisseria gonorrhoeae required 40 min for complete depiliation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis demonstrated that new, small molecular weight fragments appeared after irradiation of purified E. coli pili, suggesting that cleavage of the peptide chain rather than dissociation of pilin monomers accounted for the loss of pili structure. These observations indicate that the ultrastructural integrity and function of pili can be disrupted by ultraviolet light.

  2. Characterization of the biomechanical properties of T4 pili expressed by Streptococcus pneumoniae--a comparison between helix-like and open coil-like pili.

    Science.gov (United States)

    Castelain, Mickaël; Koutris, Efstratios; Andersson, Magnus; Wiklund, Krister; Björnham, Oscar; Schedin, Staffan; Axner, Ove

    2009-07-13

    Bacterial adhesion organelles, known as fimbria or pili, are expressed by gram-positive as well as gram-negative bacteria families. These appendages play a key role in the first steps of the invasion and infection processes, and they therefore provide bacteria with pathogenic abilities. To improve the knowledge of pili-mediated bacterial adhesion to host cells and how these pili behave under the presence of an external force, we first characterize, using force measuring optical tweezers, open coil-like T4 pili expressed by gram-positive Streptococcus pneumoniae with respect to their biomechanical properties. It is shown that their elongation behavior can be well described by the worm-like chain model and that they possess a large degree of flexibility. Their properties are then compared with those of helix-like pili expressed by gram-negative uropathogenic Escherichia coli (UPEC), which have different pili architecture. The differences suggest that these two types of pili have distinctly dissimilar mechanisms to adhere and sustain external forces. Helix-like pili expressed by UPEC bacteria adhere to host cells by single adhesins located at the distal end of the pili while their helix-like structures act as shock absorbers to dampen the irregularly shear forces induced by urine flow and to increase the cooperativity of the pili ensemble, whereas open coil-like pili expressed by S. pneumoniae adhere to cells by a multitude of adhesins distributed along the pili. It is hypothesized that these two types of pili represent different strategies of adhering to host cells in the presence of external forces. When exposed to significant forces, bacteria expressing helix-like pili remain attached by distributing the external force among a multitude of pili, whereas bacteria expressing open coil-like pili sustain large forces primarily by their multitude of binding adhesins which presumably detach sequentially.

  3. Molecular analysis of the UV-inducible pili operon from Sulfolobus acidocaldarius

    NARCIS (Netherlands)

    Wolferen, Marleen van; Ajon, Małgorzata; Driessen, Arnold J.M.; Albers, Sonja-Verena

    2013-01-01

    Upon ultraviolet (UV) stress, hyperthermophilic Sulfolobus species show a highly induced transcription of a gene cluster responsible for pili biogenesis: the UV-inducible pili operon (ups operon). This operon is involved in UV-induced pili assembly, cellular aggregation, and subsequent DNA exchange

  4. Necessity of electrically conductive pili for methanogenesis with magnetite stimulation

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    Oumei Wang

    2018-03-01

    Full Text Available Background Magnetite-mediated direct interspecies electron transfer (DIET between Geobacter and Methanosarcina species is increasingly being invoked to explain magnetite stimulation of methane production in anaerobic soils and sediments. Although magnetite-mediated DIET has been documented in defined co-cultures reducing fumarate or nitrate as the electron acceptor, the effects of magnetite have only been inferred in methanogenic systems. Methods Concentrations of methane and organic acid were analysed with a gas chromatograph and high-performance liquid chromatography, respectively. The concentration of HCl-extractable Fe(II was determined by the ferrozine method. The association of the defined co-cultures of G. metallireducens and M. barkeri with magnetite was observed with transmission electron micrographs. Results Magnetite stimulated ethanol metabolism and methane production in defined co-cultures of G. metallireducens and M. barkeri; however, magnetite did not promote methane production in co-cultures initiated with a culture of G. metallireducens that could not produce electrically conductive pili (e-pili, unlike the conductive carbon materials that facilitate DIET in the absence of e-pili. Transmission electron microscopy revealed that G. metallireducens and M. barkeri were closely associated when magnetite was present, as previously observed in G. metallireducens/G. sulfurreducens co-cultures. These results show that magnetite can promote DIET between Geobacter and Methanosarcina species, but not as a substitute for e-pili, and probably functions to facilitate electron transfer from the e-pili to Methanosarcina. Conclusion In summary, the e-pili are necessary for the stimulation of not only G. metallireducens/G. sulfurreducens, but also methanogenic G. metallireducens/M. barkeri co-cultures with magnetite.

  5. Aloe; Beyond use as cosmetics | Pili | Dar Es Salaam Medical ...

    African Journals Online (AJOL)

    Dar Es Salaam Medical Students' Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 15, No 1 (2008) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Aloe; Beyond use as cosmetics. K Pili. Abstract.

  6. Single-cell force spectroscopy of pili-mediated adhesion

    Science.gov (United States)

    Sullan, Ruby May A.; Beaussart, Audrey; Tripathi, Prachi; Derclaye, Sylvie; El-Kirat-Chatel, Sofiane; Li, James K.; Schneider, Yves-Jacques; Vanderleyden, Jos; Lebeer, Sarah; Dufrêne, Yves F.

    2013-12-01

    Although bacterial pili are known to mediate cell adhesion to a variety of substrates, the molecular interactions behind this process are poorly understood. We report the direct measurement of the forces guiding pili-mediated adhesion, focusing on the medically important probiotic bacterium Lactobacillus rhamnosus GG (LGG). Using non-invasive single-cell force spectroscopy (SCFS), we quantify the adhesion forces between individual bacteria and biotic (mucin, intestinal cells) or abiotic (hydrophobic monolayers) surfaces. On hydrophobic surfaces, bacterial pili strengthen adhesion through remarkable nanospring properties, which - presumably - enable the bacteria to resist high shear forces under physiological conditions. On mucin, nanosprings are more frequent and adhesion forces larger, reflecting the influence of specific pili-mucin bonds. Interestingly, these mechanical responses are no longer observed on human intestinal Caco-2 cells. Rather, force curves exhibit constant force plateaus with extended ruptures reflecting the extraction of membrane nanotethers. These single-cell analyses provide novel insights into the molecular mechanisms by which piliated bacteria colonize surfaces (nanosprings, nanotethers), and offer exciting avenues in nanomedicine for understanding and controlling the adhesion of microbial cells (probiotics, pathogens).

  7. Pili-Induced Clustering of N. gonorrhoeae Bacteria.

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    Johannes Taktikos

    Full Text Available Type IV pili (Tfp are prokaryotic retractable appendages known to mediate surface attachment, motility, and subsequent clustering of cells. Tfp are the main means of motility for Neisseria gonorrhoeae, the causative agent of gonorrhea. Tfp are also involved in formation of the microcolonies, which play a crucial role in the progression of the disease. While motility of individual cells is relatively well understood, little is known about the dynamics of N. gonorrhoeae aggregation. We investigate how individual N. gonorrhoeae cells, initially uniformly dispersed on flat plastic or glass surfaces, agglomerate into spherical microcolonies within hours. We quantify the clustering process by measuring the area fraction covered by the cells, number of cell aggregates, and their average size as a function of time. We observe that the microcolonies are also able to move but their mobility rapidly vanishes as the size of the colony increases. After a certain critical size they become immobile. We propose a simple theoretical model which assumes a pili-pili interaction of cells as the main clustering mechanism. Numerical simulations of the model quantitatively reproduce the experimental data on clustering and thus suggest that the agglomeration process can be entirely explained by the Tfp-mediated interactions. In agreement with this hypothesis mutants lacking pili are not able to form colonies. Moreover, cells with deficient quorum sensing mechanism show similar aggregation as the wild-type bacteria. Therefore, our results demonstrate that pili provide an essential mechanism for colony formation, while additional chemical cues, for example quorum sensing, might be of secondary importance.

  8. Pili and flagella biology, structure, and biotechnological applications.

    Science.gov (United States)

    Van Gerven, Nani; Waksman, Gabriel; Remaut, Han

    2011-01-01

    Bacteria and Archaea expose on their outer surfaces a variety of thread-like proteinaceous organelles with which they interact with their environments. These structures are repetitive assemblies of covalently or non-covalently linked protein subunits, organized into filamentous polymers known as pili ("hair"), flagella ("whips") or injectisomes ("needles"). They serve different roles in cell motility, adhesion and host invasion, protein and DNA secretion and uptake, conductance, or cellular encapsulation. Here we describe the functional, morphological and genetic diversity of these bacterial filamentous protein structures. The organized, multi-copy build-up and/or the natural function of pili and flagella have lead to their biotechnological application as display and secretion tools, as therapeutic targets or as molecular motors. We review the documented and potential technological exploitation of bacterial surface filaments in light of their structural and functional traits. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. A structural basis for sustained bacterial adhesion: biomechanical properties of CFA/I pili.

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    Andersson, Magnus; Björnham, Oscar; Svantesson, Mats; Badahdah, Arwa; Uhlin, Bernt Eric; Bullitt, Esther

    2012-02-03

    Enterotoxigenic Escherichia coli (ETEC) are a major cause of diarrheal disease worldwide. Adhesion pili (or fimbriae), such as the CFA/I (colonization factor antigen I) organelles that enable ETEC to attach efficiently to the host intestinal tract epithelium, are critical virulence factors for initiation of infection. We characterized the intrinsic biomechanical properties and kinetics of individual CFA/I pili at the single-organelle level, demonstrating that weak external forces (7.5 pN) are sufficient to unwind the intact helical filament of this prototypical ETEC pilus and that it quickly regains its original structure when the force is removed. While the general relationship between exertion of force and an increase in the filament length for CFA/I pili associated with diarrheal disease is analogous to that of P pili and type 1 pili, associated with urinary tract and other infections, the biomechanical properties of these different pili differ in key quantitative details. Unique features of CFA/I pili, including the significantly lower force required for unwinding, the higher extension speed at which the pili enter a dynamic range of unwinding, and the appearance of sudden force drops during unwinding, can be attributed to morphological features of CFA/I pili including weak layer-to-layer interactions between subunits on adjacent turns of the helix and the approximately horizontal orientation of pilin subunits with respect to the filament axis. Our results indicate that ETEC CFA/I pili are flexible organelles optimized to withstand harsh motion without breaking, resulting in continued attachment to the intestinal epithelium by the pathogenic bacteria that express these pili. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Role of type IV pili in predation by Bdellovibrio bacteriovorus.

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    Ryan M Chanyi

    Full Text Available Bdellovibrio bacteriovorus, as an obligate predator of Gram-negative bacteria, requires contact with the surface of a prey cell in order to initiate the life cycle. After attachment, the predator penetrates the prey cell outer membrane and enters the periplasmic space. Attack phase cells of B. bacteriovorus have polar Type IV pili that are required for predation. In other bacteria, these pili have the ability to extend and retract via the PilT protein. B. bacteriovorus has two pilT genes, pilT1 and pilT2, that have been implicated in the invasion process. Markerless in-frame deletion mutants were constructed in a prey-independent mutant to assess the role of PilT1 and PilT2 in the life cycle. When predation was assessed using liquid cocultures, all mutants produced bdelloplasts of Escherichia coli. These results demonstrated that PilT1 and PilT2 are not required for invasion of prey cells. Predation of the mutants on biofilms of E. coli was also assessed. Wild type B. bacteriovorus 109JA and the pilT1 mutant decreased the mass of the biofilm to 35.4% and 27.9% respectively. The pilT1pilT2 mutant was able to prey on the biofilm, albeit less efficiently with 50.2% of the biofilm remaining. The pilT2 mutant was unable to disrupt the biofilm, leaving 92.5% of the original biofilm after predation. The lack of PilT2 function may impede the ability of B. bacteriovorus to move in the extracellular polymeric matrix and find a prey cell. The role of Type IV pili in the life cycle of B. bacteriovorus is thus for initial recognition of and attachment to a prey cell in liquid cocultures, and possibly for movement within the matrix of a biofilm.

  11. Mitis group streptococci express variable pilus islet 2 pili.

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    Zähner, Dorothea; Gandhi, Ashish R; Yi, Hong; Stephens, David S

    2011-01-01

    Streptococcus oralis, Streptococcus mitis, and Streptococcus sanguinis are members of the Mitis group of streptococci and agents of oral biofilm, dental plaque and infective endocarditis, disease processes that involve bacteria-bacteria and bacteria-host interactions. Their close relative, the human pathogen S. pneumoniae uses pilus-islet 2 (PI-2)-encoded pili to facilitate adhesion to eukaryotic cells. PI-2 pilus-encoding genetic islets were identified in S. oralis, S. mitis, and S. sanguinis, but were absent from other isolates of these species. The PI-2 islets resembled the genetic organization of the PI-2 islet of S. pneumoniae, but differed in the genes encoding the structural pilus proteins PitA and PitB. Two and three variants of pitA (a pseudogene in S. pneumoniae) and pitB, respectively, were identified that showed ≈20% difference in nucleotide as well as corresponding protein sequence. Species-independent combinations of pitA and pitB variants indicated prior intra- and interspecies horizontal gene transfer events. Polyclonal antisera developed against PitA and PitB of S. oralis type strain ATCC35037 revealed that PI-2 pili in oral streptococci were composed of PitA and PitB. Electronmicrographs showed pilus structures radiating >700 nm from the bacterial surface in the wild type strain, but not in an isogenic PI-2 deletion mutant. Anti-PitB-antiserum only reacted with pili containing the same PitB variant, whereas anti-PitA antiserum was cross-reactive with the other PitA variant. Electronic multilocus sequence analysis revealed that all PI-2-encoding oral streptococci were closely-related and cluster with non-PI-2-encoding S. oralis strains. This is the first identification of PI-2 pili in Mitis group oral streptococci. The findings provide a striking example of intra- and interspecies horizontal gene transfer. The PI-2 pilus diversity provides a possible key to link strain-specific bacterial interactions and/or tissue tropisms with pathogenic traits

  12. Mitis group streptococci express variable pilus islet 2 pili.

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    Dorothea Zähner

    Full Text Available Streptococcus oralis, Streptococcus mitis, and Streptococcus sanguinis are members of the Mitis group of streptococci and agents of oral biofilm, dental plaque and infective endocarditis, disease processes that involve bacteria-bacteria and bacteria-host interactions. Their close relative, the human pathogen S. pneumoniae uses pilus-islet 2 (PI-2-encoded pili to facilitate adhesion to eukaryotic cells.PI-2 pilus-encoding genetic islets were identified in S. oralis, S. mitis, and S. sanguinis, but were absent from other isolates of these species. The PI-2 islets resembled the genetic organization of the PI-2 islet of S. pneumoniae, but differed in the genes encoding the structural pilus proteins PitA and PitB. Two and three variants of pitA (a pseudogene in S. pneumoniae and pitB, respectively, were identified that showed ≈20% difference in nucleotide as well as corresponding protein sequence. Species-independent combinations of pitA and pitB variants indicated prior intra- and interspecies horizontal gene transfer events. Polyclonal antisera developed against PitA and PitB of S. oralis type strain ATCC35037 revealed that PI-2 pili in oral streptococci were composed of PitA and PitB. Electronmicrographs showed pilus structures radiating >700 nm from the bacterial surface in the wild type strain, but not in an isogenic PI-2 deletion mutant. Anti-PitB-antiserum only reacted with pili containing the same PitB variant, whereas anti-PitA antiserum was cross-reactive with the other PitA variant. Electronic multilocus sequence analysis revealed that all PI-2-encoding oral streptococci were closely-related and cluster with non-PI-2-encoding S. oralis strains.This is the first identification of PI-2 pili in Mitis group oral streptococci. The findings provide a striking example of intra- and interspecies horizontal gene transfer. The PI-2 pilus diversity provides a possible key to link strain-specific bacterial interactions and/or tissue tropisms with

  13. Pili of oral Streptococcus sanguinis bind to fibronectin and contribute to cell adhesion.

    Science.gov (United States)

    Okahashi, Nobuo; Nakata, Masanobu; Sakurai, Atsuo; Terao, Yutaka; Hoshino, Tomonori; Yamaguchi, Masaya; Isoda, Ryutaro; Sumitomo, Tomoko; Nakano, Kazuhiko; Kawabata, Shigetada; Ooshima, Takashi

    2010-01-08

    Streptococcus sanguinis is a predominant bacterium in the human oral cavity and occasionally causes infective endocarditis. We identified a unique cell surface polymeric structure named pili in this species and investigated its functions in regard to its potential virulence. Pili of S. sanguinis strain SK36 were shown to be composed of three distinctive pilus proteins (PilA, PilB, and PilC), and a pili-deficient mutant demonstrated reduced bacterial adherence to HeLa and human oral epithelial cells. PilC showed a binding ability to fibronectin, suggesting that pili are involved in colonization by this species. In addition, ATCC10556, a standard S. sanguinis strain, was unable to produce pili due to defective pilus genes, which indicates a diversity of pilus expression among various S. sanguinis strains. Copyright 2009 Elsevier Inc. All rights reserved.

  14. Mechanisms for Electron Transfer Through Pili to Fe(III) Oxide in Geobacter

    Energy Technology Data Exchange (ETDEWEB)

    Lovley, Derek R. [Univ. of Massachusetts, Amherst, MA (United States)

    2015-03-09

    The purpose of these studies was to aid the Department of Energy in its goal of understanding how microorganisms involved in the bioremediation of metals and radionuclides sustain their activity in the subsurface. This information is required in order to incorporate biological processes into decision making for environmental remediation and long-term stewardship of contaminated sites. The proposed research was designed to elucidate the mechanisms for electron transfer to Fe(III) oxides in Geobacter species because Geobacter species are abundant dissimilatory metal-reducing microorganisms in a diversity of sites in which uranium is undergoing natural attenuation via the reduction of soluble U(VI) to insoluble U(IV) or when this process is artificially stimulated with the addition of organic electron donors. This study investigated the novel, but highly controversial, concept that the final conduit for electron transfer to Fe(III) oxides are electrically conductive pili. The specific objectives were to: 1) further evaluate the conductivity along the pili of Geobacter sulfurreducens and related organisms; 2) determine the mechanisms for pili conductivity; and 3) investigate the role of pili in Fe(III) oxide reduction. The studies demonstrated that the pili of G. sulfurreducens are conductive along their length. Surprisingly, the pili possess a metallic-like conductivity similar to that observed in synthetic organic conducting polymers such as polyaniline. Detailed physical analysis of the pili, as well as studies in which the structure of the pili was genetically modified, demonstrated that the metallic-like conductivity of the pili could be attributed to overlapping pi-pi orbitals of aromatic amino acids. Other potential mechanisms for conductivity, such as electron hopping between cytochromes associated with the pili were definitively ruled out. Pili were also found to be essential for Fe(III) oxide reduction in G. metallireducens. Ecological studies demonstrated

  15. The role of pili in Bacillus cereus intraocular infection.

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    Callegan, Michelle C; Parkunan, Salai Madhumathi; Randall, C Blake; Coburn, Phillip S; Miller, Frederick C; LaGrow, Austin L; Astley, Roger A; Land, Craig; Oh, So-Young; Schneewind, Olaf

    2017-06-01

    Bacterial endophthalmitis is a potentially blinding intraocular infection. The bacterium Bacillus cereus causes a devastating form of this disease which progresses rapidly, resulting in significant inflammation and loss of vision within a few days. The outer surface of B. cereus incites the intraocular inflammatory response, likely through interactions with innate immune receptors such as TLRs. This study analyzed the role of B. cereus pili, adhesion appendages located on the bacterial surface, in experimental endophthalmitis. To test the hypothesis that the presence of pili contributed to intraocular inflammation and virulence, we analyzed the progress of experimental endophthalmitis in mouse eyes infected with wild type B. cereus (ATCC 14579) or its isogenic pilus-deficient mutant (ΔbcpA-srtD-bcpB or ΔPil). One hundred CFU were injected into the mid-vitreous of one eye of each mouse. Infections were analyzed by quantifying intraocular bacilli and retinal function loss, and by histology from 0 to 12 h postinfection. In vitro growth and hemolytic phenotypes of the infecting strains were also compared. There was no difference in hemolytic activity (1:8 titer), motility, or in vitro growth (p > 0.05, every 2 h, 0-18 h) between wild type B. cereus and the ΔPil mutant. However, infected eyes contained greater numbers of wild type B. cereus than ΔPil during the infection course (p ≤ 0.05, 3-12 h). Eyes infected with wild type B. cereus experienced greater losses in retinal function than eyes infected with the ΔPil mutant, but the differences were not always significant. Eyes infected with ΔPil or wild type B. cereus achieved similar degrees of severe inflammation. The results indicated that the intraocular growth of pilus-deficient B. cereus may have been better controlled, leading to a trend of greater retinal function in eyes infected with the pilus-deficient strain. Although this difference was not enough to significantly alter the severity

  16. A Structural Basis for Sustained Bacterial Adhesion – Biomechanical Properties of CFA/I Pili

    OpenAIRE

    Andersson, Magnus; Björnham, Oscar; Svantesson, Mats; Badahdah, Arwa; Uhlin, Bernt Eric; Bullitt, Esther

    2011-01-01

    Enterotoxigenic Escherichia coli (ETEC) are a major cause of diarrheal disease worldwide. Adhesion pili (or fimbriae), such as the CFA/I (colonization factor antigen I) organelles that enable ETEC to attach efficiently to the host intestinal tract epithelium, are critical virulence factors for initiation of infection. We characterized at single organelle level the intrinsic biomechanical properties and kinetics of individual CFA/I pili, demonstrating that weak external forces (7.5 pN) are suf...

  17. Diversity, assembly and regulation of archaeal type IV pili-like and non-type-IV pili-like surface structures.

    Science.gov (United States)

    Lassak, Kerstin; Ghosh, Abhrajyoti; Albers, Sonja-Verena

    2012-01-01

    Archaea have evolved fascinating surface structures allowing rapid adaptation to changing environments. The archaeal surface appendages display such diverse biological roles as motility, adhesion, biofilm formation, exchange of genetic material and species-specific interactions and, in turn, increase fitness of the cells. Intriguingly, despite sharing the same functions with their bacterial counterparts, the assembly mechanism of many archaeal surface structures is rather related to assembly of bacterial type IV pili. This review summarizes our state-of-the-art knowledge about unique structural and biochemical properties of archaeal surface appendages with a particular focus on archaeal type IV pili-like structures. The latter comprise not only widely distributed archaella (formerly known as archaeal flagella), but also different highly specialized archaeal pili, which are often restricted to certain species. Recent findings regarding assembly mechanisms, structural aspects and physiological roles of these type IV pili-like structures will be discussed in detail. Recently, first regulatory proteins involved in transition from both planktonic to sessile lifestyle and in assembly of archaella were identified. To conclude, we provide novel insights into regulatory mechanisms underlying the assembly of archaeal surface structures. Copyright © 2012. Published by Elsevier Masson SAS.

  18. Multiscale modeling of bacterial colonies: how pili mediate the dynamics of single cells and cellular aggregates

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    Pönisch, Wolfram; Weber, Christoph A.; Juckeland, Guido; Biais, Nicolas; Zaburdaev, Vasily

    2017-01-01

    Neisseria gonorrhoeae is the causative agent of one of the most common sexually transmitted diseases, gonorrhea. Over the past two decades there has been an alarming increase of reported gonorrhea cases where the bacteria were resistant to the most commonly used antibiotics thus prompting for alternative antimicrobial treatment strategies. The crucial step in this and many other bacterial infections is the formation of microcolonies, agglomerates consisting of up to several thousands of cells. The attachment and motility of cells on solid substrates as well as the cell-cell interactions are primarily mediated by type IV pili, long polymeric filaments protruding from the surface of cells. While the crucial role of pili in the assembly of microcolonies has been well recognized, the exact mechanisms of how they govern the formation and dynamics of microcolonies are still poorly understood. Here, we present a computational model of individual cells with explicit pili dynamics, force generation and pili-pili interactions. We employ the model to study a wide range of biological processes, such as the motility of individual cells on a surface, the heterogeneous cell motility within the large cell aggregates, and the merging dynamics and the self-assembly of microcolonies. The results of numerical simulations highlight the central role of pili generated forces in the formation of bacterial colonies and are in agreement with the available experimental observations. The model can quantify the behavior of multicellular bacterial colonies on biologically relevant temporal and spatial scales and can be easily adjusted to include the geometry and pili characteristics of various bacterial species. Ultimately, the combination of the microbiological experimental approach with the in silico model of bacterial colonies might provide new qualitative and quantitative insights on the development of bacterial infections and thus pave the way to new antimicrobial treatments.

  19. Pili torti and multiple facial milia as an expression of ectodermal dysplasia in monozygotic twins

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    Monika Sikorska

    2014-03-01

    Full Text Available Introduction . Genodermatoses – congenital diseases with diverse clinical presentation – are caused by ectodermal defects. pili torti and milia may be features of these defects. Concomitantly these symptoms are present in rare genodermatoses: Bazex-Dupre-Christol syndrome and Jackson-Lawler syndrome. Objective. Presentation of monozygotic twins with identical hair structure disturbances typical for pili torti and multiple facial milia and review of syndromes and diseases with pili torti and/or milia, with particular reference to Bazex-Dupre-Christol syndrome. Case report . Three-year-old monozygotic twins with identical disturbances of the hair, which was dry, brittle, torn and showed in microscopic examination features typical for pili torti – twisting of the hair shaft by 180 ° . The scalp was overdried and scaly. Numerous milia on the face of both girls appeared at the age of 2 years and were noticed during the examination. The remaining structures derived from the ectoderm were normal. The patients were treated with adapalene cream applied once a day with partial improvement of follicular lesions on the face in both sisters. Conclusions . Coexistence of pili torti and multiple milia in twins indicates the genetic background of these disturbances. Due to potential risk of development of skin carcinoma in future, the patients require close follow-up.

  20. Involvement of T6 pili in biofilm formation by serotype M6 Streptococcus pyogenes.

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    Kimura, Keiji Richard; Nakata, Masanobu; Sumitomo, Tomoko; Kreikemeyer, Bernd; Podbielski, Andreas; Terao, Yutaka; Kawabata, Shigetada

    2012-02-01

    The group A streptococcus (GAS) Streptococcus pyogenes is known to cause self-limiting purulent infections in humans. The role of GAS pili in host cell adhesion and biofilm formation is likely fundamental in early colonization. Pilus genes are found in the FCT (fibronectin-binding protein, collagen-binding protein, and trypsin-resistant antigen) genomic region, which has been classified into nine subtypes based on the diversity of gene content and nucleotide sequence. Several epidemiological studies have indicated that FCT type 1 strains, including serotype M6, produce large amounts of monospecies biofilm in vitro. We examined the direct involvement of pili in biofilm formation by serotype M6 clinical isolates. In the majority of tested strains, deletion of the tee6 gene encoding pilus shaft protein T6 compromised the ability to form biofilm on an abiotic surface. Deletion of the fctX and srtB genes, which encode pilus ancillary protein and class C pilus-associated sortase, respectively, also decreased biofilm formation by a representative strain. Unexpectedly, these mutant strains showed increased bacterial aggregation compared with that of the wild-type strain. When the entire FCT type 1 pilus region was ectopically expressed in serotype M1 strain SF370, biofilm formation was promoted and autoaggregation was inhibited. These findings indicate that assembled FCT type 1 pili contribute to biofilm formation and also function as attenuators of bacterial aggregation. Taken together, our results show the potential role of FCT type 1 pili in the pathogenesis of GAS infections.

  1. Multiple roles of Pseudomonas aeruginosa TBCF10839 PilY1 in motility, transport and infection

    DEFF Research Database (Denmark)

    Bohn, Yu-Sing Tammy; Brandes, Gudrun; Rakhimova, Elza

    2009-01-01

    Polymorphonuclear neutrophils are the most important mammalian host defence cells against infections with Pseudomonas aeruginosa. Screening of a signature tagged mutagenesis library of the non-piliated P. aeruginosa strain TBCF10839 uncovered that transposon inactivation of its pilY1 gene rendere...

  2. Assembly mechanism of FCT region type 1 pili in serotype M6 Streptococcus pyogenes.

    Science.gov (United States)

    Nakata, Masanobu; Kimura, Keiji Richard; Sumitomo, Tomoko; Wada, Satoshi; Sugauchi, Akinari; Oiki, Eiji; Higashino, Miharu; Kreikemeyer, Bernd; Podbielski, Andreas; Okahashi, Nobuo; Hamada, Shigeyuki; Isoda, Ryutaro; Terao, Yutaka; Kawabata, Shigetada

    2011-10-28

    The human pathogen Streptococcus pyogenes produces diverse pili depending on the serotype. We investigated the assembly mechanism of FCT type 1 pili in a serotype M6 strain. The pili were found to be assembled from two precursor proteins, the backbone protein T6 and ancillary protein FctX, and anchored to the cell wall in a manner that requires both a housekeeping sortase enzyme (SrtA) and pilus-associated sortase enzyme (SrtB). SrtB is primarily required for efficient formation of the T6 and FctX complex and subsequent polymerization of T6, whereas proper anchoring of the pili to the cell wall is mainly mediated by SrtA. Because motifs essential for polymerization of pilus backbone proteins in other Gram-positive bacteria are not present in T6, we sought to identify the functional residues involved in this process. Our results showed that T6 encompasses the novel VAKS pilin motif conserved in streptococcal T6 homologues and that the lysine residue (Lys-175) within the motif and cell wall sorting signal of T6 are prerequisites for isopeptide linkage of T6 molecules. Because Lys-175 and the cell wall sorting signal of FctX are indispensable for substantial incorporation of FctX into the T6 pilus shaft, FctX is suggested to be located at the pilus tip, which was also implied by immunogold electron microscopy findings. Thus, the elaborate assembly of FCT type 1 pili is potentially organized by sortase-mediated cross-linking between sorting signals and the amino group of Lys-175 positioned in the VAKS motif of T6, thereby displaying T6 and FctX in a temporospatial manner.

  3. Calcium-Enhanced Twitching Motility in Xylella fastidiosa Is Linked to a Single PilY1 Homolog.

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    Cruz, Luisa F; Parker, Jennifer K; Cobine, Paul A; De La Fuente, Leonardo

    2014-12-01

    The plant-pathogenic bacterium Xylella fastidiosa is restricted to the xylem vessel environment, where mineral nutrients are transported through the plant host; therefore, changes in the concentrations of these elements likely impact the growth and virulence of this bacterium. Twitching motility, dependent on type IV pili (TFP), is required for movement against the transpiration stream that results in basipetal colonization. We previously demonstrated that calcium (Ca) increases the motility of X. fastidiosa, although the mechanism was unknown. PilY1 is a TFP structural protein recently shown to bind Ca and to regulate twitching and adhesion in bacterial pathogens of humans. Sequence analysis identified three pilY1 homologs in X. fastidiosa (PD0023, PD0502, and PD1611), one of which (PD1611) contains a Ca-binding motif. Separate deletions of PD0023 and PD1611 resulted in mutants that still showed twitching motility and were not impaired in attachment or biofilm formation. However, the response of increased twitching at higher Ca concentrations was lost in the pilY1-1611 mutant. Ca does not modulate the expression of any of the X. fastidiosa PilY1 homologs, although it increases the expression of the retraction ATPase pilT during active movement. The evidence presented here suggests functional differences between the PilY1 homologs, which may provide X. fastidiosa with an adaptive advantage in environments with high Ca concentrations, such as xylem sap. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  4. The three-dimensional structure of CFA/I adhesion pili: traveler's diarrhea bacteria hang on by a spring.

    Science.gov (United States)

    Mu, Xiang-Qi; Savarino, Stephen J; Bullitt, Esther

    2008-02-22

    To survive the harsh environment of a churning intestinal tract, bacteria attach to the host epithelium via thin fibers called pili (or fimbriae). Enterotoxigenic Escherichia coli bacteria expressing colonization factor antigen I (CFA/I) pili and related pili are the most common known bacterial cause of diarrheal disease, including traveler's diarrhea. CFA/I pili, assembled via the alternate chaperone pathway, are essential for binding and colonization of the small bowel by these pathogenic bacteria. Herein, we elucidate unique structural features of CFA/I pili that appear to optimize their function as bacterial tethers in the intestinal tract. Using transmission electron microscopy of negatively stained samples in combination with iterative three-dimensional helical reconstruction methods for image processing, we determined the structure of the CFA/I pilus filament. Our results indicate that strong end-to-end protein interactions and weak interactions between the coils of a sturdy spring-like helix provide the combination of strength, stability, and flexibility required to sustain bacterial adhesion and incite intestinal disease. We propose that CFA/I pili behave like a spring to maintain attachment to the gut lining during vortex mixing and downward flow of the intestinal contents, thereby persisting long enough for these bacteria to colonize the host epithelium and cause enteric disease.

  5. Structural characterization of CFA/III and Longus type IVb pili from enterotoxigenic Escherichia coli.

    Science.gov (United States)

    Kolappan, Subramaniapillai; Roos, Justin; Yuen, Alex S W; Pierce, Owen M; Craig, Lisa

    2012-05-01

    The type IV pili are helical filaments found on many Gram-negative pathogenic bacteria, with multiple diverse roles in pathogenesis, including microcolony formation, adhesion, and twitching motility. Many pathogenic enterotoxigenic Escherichia coli (ETEC) isolates express one of two type IV pili belonging to the type IVb subclass: CFA/III or Longus. Here we show a direct correlation between CFA/III expression and ETEC aggregation, suggesting that these pili, like the Vibrio cholerae toxin-coregulated pili (TCP), mediate microcolony formation. We report a 1.26-Å resolution crystal structure of CofA, the major pilin subunit from CFA/III. CofA is very similar in structure to V. cholerae TcpA but possesses a 10-amino-acid insertion that replaces part of the α2-helix with an irregular loop containing a 3(10)-helix. Homology modeling suggests a very similar structure for the Longus LngA pilin. A model for the CFA/III pilus filament was generated using the TCP electron microscopy reconstruction as a template. The unique 3(10)-helix insert fits perfectly within the gap between CofA globular domains. This insert, together with differences in surface-exposed residues, produces a filament that is smoother and more negatively charged than TCP. To explore the specificity of the type IV pilus assembly apparatus, CofA was expressed heterologously in V. cholerae by replacing the tcpA gene with that of cofA within the tcp operon. Although CofA was synthesized and processed by V. cholerae, no CFA/III filaments were detected, suggesting that the components of the type IVb pilus assembly system are highly specific to their pilin substrates.

  6. Uptake of extracellular DNA: Competence induced pili in natural transformation of Streptococcus pneumoniae

    Science.gov (United States)

    Muschiol, Sandra; Balaban, Murat; Normark, Staffan; Henriques-Normark, Birgitta

    2015-01-01

    Transport of DNA across bacterial membranes involves complex DNA uptake systems. In Gram-positive bacteria, the DNA uptake machinery shares fundamental similarities with type IV pili and type II secretion systems. Although dedicated pilus structures, such as type IV pili in Gram-negative bacteria, are necessary for efficient DNA uptake, the role of similar structures in Gram-positive bacteria is just beginning to emerge. Recently two essentially very different pilus structures composed of the same major pilin protein ComGC were proposed to be involved in transformation of the Gram-positive bacterium Streptococcus pneumoniae – one is a long, thin, type IV pilus-like fiber with DNA binding capacity and the other one is a pilus structure that was thicker, much shorter and not able to bind DNA. Here we discuss how competence induced pili, either by pilus retraction or by a transient pilus-related opening in the cell wall, may mediate DNA uptake in S. pneumoniae. PMID:25640084

  7. Identification of capsule, biofilm, lateral flagellum, and type IV pili in Vibrio mimicus strains.

    Science.gov (United States)

    Tercero-Alburo, J J; González-Márquez, H; Bonilla-González, E; Quiñones-Ramírez, E I; Vázquez-Salinas, C

    2014-11-01

    Vibrio mimicus is a bacterium that causes gastroenteritis; it is closely related to Vibrio cholerae, and can cause acute diarrhea like cholera- or dysentery-type diarrhea. It is distributed worldwide. Factors associated with virulence (such as hemolysins, enterotoxins, proteases, phospholipases, aerobactin, and hemagglutinin) have been identified; however, its pathogenicity mechanism is still unknown. In pathogenic Vibrio species such as V. cholerae, Vibrio. parahaemolyticus and Vibrio vulnificus, capsule, biofilms, lateral flagellum, and type IV pili are structures described as essential for pathogenicity. These structures had not been described in V. mimicus until this work. We used 20 V. mimicus strains isolated from water (6), oyster (9), and fish (5) samples and we were able to identify the capsule, biofilm, lateral flagellum, and type IV pili through phenotypic tests, electron microscopy, PCR, and sequencing. In all tested strains, we observed and identified the presence of capsular exopolysaccharide, biofilm formation in an in vitro model, as well as swarming, multiple flagellation, and pili. In addition, we identified homologous genes to those described in other bacteria of the genus in which these structures have been found. Identification of these structures in V. mimicus is a contribution to the biology of this organism and can help to reveal its pathogenic behavior. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Surface expression and functional characterization of recombinant SpaFED pili in Lactococcus lactis

    OpenAIRE

    Rintahaka, Johanna; Yu, Xia; Kant, Ravi; Palva, Airi; von Ossowski, Ingemar

    2014-01-01

    A noticeable genomic feature of many piliated Gram-positive bacterial species is the presence of more than one pilus-encoding operon. Paradigmatically, the gut-adapted Lactobacillus rhamnosus GG strain contains two different fimbrial operons in its genome. However, whereas one of these operons (called spaCBA) is encoding for the functionally mucus-/collagen-binding SpaCBA pilus, for the other operon (called spaFED) any native expression of the SpaFED-called pili is still the subject of some u...

  9. Two type IV pili of Vibrio parahaemolyticus play different roles in biofilm formation.

    Science.gov (United States)

    Shime-Hattori, Akiko; Iida, Tetsuya; Arita, Michiko; Park, Kwon-Sam; Kodama, Toshio; Honda, Takeshi

    2006-11-01

    Vibrio parahaemolyticus RIMD2210633 has two sets of type IV-A pilus genes. One set is similar to that found in other Gram-negative bacteria, such as Pseudomonas aeruginosa, Vibrio cholerae (chitin-regulated pilus; ChiRP), and Vibrio vulnificus. The other is homologous to the genes for the mannose-sensitive hemagglutinin (MSHA) pilus. In this study, we analyzed the effects of the deletions in the pilin genes for each type IV pilus (the ChiRP and the MSHA pilus) on biofilm formation. Although the MSHA pilin mutant formed aggregates, the number of bacteria that attached directly to the coverslip was reduced, suggesting that this pilus contributes to the bacterial attachment to the surface of the coverslip. In contrast, the ChiRP mutant attached to the surface of the coverslip, but did not form aggregates, suggesting that ChiRP plays a role in bacterial agglutination during biofilm formation. These results suggest that the two type IV pili of V. parahaemolyticus contribute to biofilm formation in different ways. Both mutants showed a lower fitness for adsorption onto chitin particles than that of the wild type. Collectively, these data suggest that the use of two type IV pili is a refined strategy of V. parahaemolyticus for survival in natural environments.

  10. Canarium ovatum Engl. (Pili exocarp crude extract as functional food colorant incorporated in yogurt developed product

    Directory of Open Access Journals (Sweden)

    Aril-dela Cruz, J.V.,

    2017-09-01

    Full Text Available Canarium ovatum Engl. (Pili, a locally grown plant in the Philippines, bears highly pigmented fruits. In this research study, the deeply pigmented fruit exocarp was evaluated for phytochemical contents, functional properties and possible application to yogurt as a colorant. Spectrophotometric analysis of the extract revealed high phenolic and flavonoid content, particularly anthocyanins (17.5 mg CE/g DW of the sample. The pigment extract also exhibited potential antioxidant activities as determined by DPPH and FRAP assays and did not show any inhibitory activity against gut normal flora, Escherichia coli, but also failed to express cytotoxic activity against HCT116 colon cancer cell line. Stability tests showed decreased redness with increasing temperature or pH. The pigment exhibited excellent color retention in yogurt during the two-week storage at 4oC. Sensory evaluation showed a slight difference in over-all acceptability between natural and synthetic-colored yogurt. Thus, Pili exocarp extract can be used as a functional food colorant in yogurt.

  11. A helynevek szerepe az alternatív ideologikus gondolkodásban I. A Pilis-kultusz esete [The role of place names in an alternative ideological mindset I. The case of the Pilis Cult

    Directory of Open Access Journals (Sweden)

    Imreh, Réka

    2014-12-01

    Full Text Available This paper focuses on the role of place names in defining and legitimizing the identity of a subculture through the example of a complex contemporary alternative social phenomenon known as the Pilis Cult. The Pilis Cult, which is also linked with some other alternative theories (Sumerian–Hungarian linguistic affinity, root linguistics, The Holy Crown Doctrine, claims that the Pilis Mountains as a spiritual space have a special role in Hungarian history. In the specific attitude to language and place names adopted by this subculture, one can recognize elements similar to those of ancient and medieval magical thinking. These can be observed in the interpretation of place names of the mountains, in which associations connected to the phonetic forms or the semantics of the place names may turn these toponyms into “telling names”, proving 120 Imreh Réka the antiquity and spirituality of the area. This etymological-associative narration is illustrated in the paper with the examples of the place names Pilis and Dobogó-kő. The interpretations of these names commingling with the alternative ideas connected to the denotata themselves (e.g. heart chakra theory; Proto-Buda Theories establish a unified argumentation framework. The paper argues that even a linguistically unorthodox subculture – alongside its specific ideology – may emphasize aspects of the study of place names through which our knowledge can be expanded with respect, for instance, to the functional logic behind place names.

  12. Functional Analysis of Lactobacillus rhamnosus GG Pili in Relation to Adhesion and Immunomodulatory Interactions with Intestinal Epithelial Cells

    NARCIS (Netherlands)

    Lebeer, S.; Claes, I.J.; Tytgat, H.L.P.; Verhoeven, T.L.A.; Marien, E.; Ossowski, von I.; Reunanen, J.; Palva, A.; Vos, de W.M.; Keersmaecker, de S.C.; Vanderleyden, J.

    2012-01-01

    Lactobacillus rhamnosus GG, a probiotic with good survival capacity in the human gut, has well-documented adhesion properties and health effects. Recently, spaCBA-encoded pili that bind to human intestinal mucus were identified on its cell surface. Here, we report on the phenotypic analysis of a

  13. Patients with a new variant of endemic pemphigus foliaceus have autoantibodies against arrector pili muscle, colocalizing with MYZAP, p0071, desmoplakins 1 and 2 and ARVCF.

    Science.gov (United States)

    Abreu-Velez, A M; Valencia-Yepes, C A; Upegui-Zapata, Y A; Upegui-Quiceno, E; Mesa-Herrera, N R; Velazquez-Velez, J E; Howard, M S

    2017-12-01

    We identified a new variant of endemic pemphigus foliaceus in El Bagre, Colombia, South America, which we term El Bagre-EPF, and observed reactivity to arrector pili muscle (APM), thus we tested for autoimmunity to APM. We took skin biopsies from 30 patients with El Bagre-EPF and 30 healthy controls (HCs) matched by age, sex and occupation, who were all from the endemic area, and tested these using direct immunofluorescence (DIF), confocal microscopy, immunohistochemistry and immunoblotting (IB). Of the 30 patients with El Bagre-EPF, 27 had autoantibodies to APM that colocalized with commercial antibodies to myocardium-enriched zonula occludens-1-associated protein (MYZAP), desmoplakin (DP)1 and DP2, plakophilin 4, and Armadillo repeat gene deleted in velo-cardio-facial syndrome (ARVCF) (P EPF have autoantibodies to APM, colocalizing with the antibodies MYZAP, ARVCF, p0071, DP1 and DP2, suggesting that these molecules are El Bagre-EPF antigens. Further, all of these antigens represent components of cell junctions, indicating that the immune response is directed, at least partially, against cell junctions. The immune response in patients affected by El Bagre-EPF is polyclonal, and it includes B and T lymphocytes, mast cells, IgG, IgA, IgM, IgD, IgE, fibrinogen, albumin, complement/C1q, C3c and C4. © 2017 British Association of Dermatologists.

  14. Diarrhea-associated biofilm formed by enteroaggregative Escherichia coli and aggregative Citrobacter freundii: a consortium mediated by putative F pili

    Directory of Open Access Journals (Sweden)

    Araújo Ana CG

    2010-02-01

    Full Text Available Abstract Background Enteroaggregative Escherichia coli (EAEC are enteropathogenic strains identified by the aggregative adhesion (AA pattern that share the capability to form biofilms. Citrobacter freundii is classically considered as an indigenous intestinal species that is sporadically associated with diarrhea. Results During an epidemiologic study focusing on infantile diarrhea, aggregative C. freundii (EACF and EAEC strains were concomitantly recovered from a severe case of mucous diarrhea. Thereby, the occurrence of synergic events involving these strains was investigated. Coinfection of HeLa cells with EACF and EAEC strains showed an 8-fold increase in the overall bacterial adhesion compared with single infections (P traA were capable of forming bacterial aggregates only in the presence of EACF. Scanning electronic microscopy analyses revealed that bacterial aggregates as well as enhanced biofilms formed by EACF and traA-positive EAEC were mediated by non-bundle forming, flexible pili. Moreover, mixed biofilms formed by EACF and traA-positive EAEC strains were significantly reduced using nonlethal concentration of zinc, a specific inhibitor of F pili. In addition, EAEC strains isolated from diarrheic children frequently produced single biofilms sensitive to zinc. Conclusions Putative F pili expressed by EAEC strains boosted mixed biofilm formation when in the presence of aggregative C. freundii.

  15. Functional Analysis of Lactobacillus rhamnosus GG Pili in Relation to Adhesion and Immunomodulatory Interactions with Intestinal Epithelial Cells

    Science.gov (United States)

    Claes, Ingmar; Tytgat, Hanne L. P.; Verhoeven, Tine L. A.; Marien, Eyra; von Ossowski, Ingemar; Reunanen, Justus; Palva, Airi; de Vos, Willem M.; De Keersmaecker, Sigrid C. J.; Vanderleyden, Jos

    2012-01-01

    Lactobacillus rhamnosus GG, a probiotic with good survival capacity in the human gut, has well-documented adhesion properties and health effects. Recently, spaCBA-encoded pili that bind to human intestinal mucus were identified on its cell surface. Here, we report on the phenotypic analysis of a spaCBA pilus knockout mutant in comparison with the wild type and other adhesin mutants. The SpaCBA pilus of L. rhamnosus GG showed to be key for efficient adherence to the Caco-2 intestinal epithelial cell (IEC) line and biofilm formation. Moreover, the spaCBA mutant induces an elevated level of interleukin-8 (IL-8) mRNA in Caco-2 cells compared to the wild type, possibly involving an interaction of lipoteichoic acid with Toll-like receptor 2. In contrast, an L. rhamnosus GG mutant without exopolysaccharides but with an increased exposure of pili leads to the reduced expression of IL-8. Using Transwells to partition bacteria from Caco-2 cells, IL-8 induction is blocked completely regardless of whether wild-type or mutant L. rhamnosus GG cells are used. Taken together, our data suggest that L. rhamnosus GG SpaCBA pili, while promoting strong adhesive interactions with IECs, have a functional role in balancing IL-8 mRNA expression induced by surface molecules such as lipoteichoic acid. PMID:22020518

  16. Etlik Piliçlerin Beslenmesinde Böceklerin Kullanılması

    Directory of Open Access Journals (Sweden)

    Özgün Işık

    2017-07-01

    Full Text Available Hızlı ve yüksek canlı ağırlık artışının esas alındığı etlik piliç üretiminde, hayvanların besin maddesi ve enerji ihtiyaçlarını karşılamak önemlidir. Bu ihtiyaçları karşılamak için kullanılan geleneksel yem hammaddelerinin üretiminde ve ithalatında yaşanan sorunlar nedeniyle, alternatif yem hammaddeleri aranmaktadır. Bu amaçla tavukların doğal rasyonlarında bulunan böcekler umut verici gözükmektedir. Özellikle protein yemlerine alternatif olarak üzerinde en çok çalışma yapılan türler arasında asker sineği (Hermetica illucens, karasinek (Musca domestica, çayır cırcır böceği (Gryllus testaceus, ipek böceği (Bombyx mori, çekirge (Acrididae ve un kurdu (Tenebrio molitor yer almaktadır.

  17. Type IV pili of Acidithiobacillus ferrooxidans can transfer electrons from extracellular electron donors.

    Science.gov (United States)

    Li, Yongquan; Li, Hongyu

    2014-03-01

    Studies on Acidithiobacillus ferrooxidans accepting electrons from Fe(II) have previously focused on cytochrome c. However, we have discovered that, besides cytochrome c, type IV pili (Tfp) can transfer electrons. Here, we report conduction by Tfp of A. ferrooxidans analyzed with a conducting-probe atomic force microscope (AFM). The results indicate that the Tfp of A. ferrooxidans are highly conductive. The genome sequence of A. ferrooxidans ATCC 23270 contains two genes, pilV and pilW, which code for pilin domain proteins with the conserved amino acids characteristic of Tfp. Multiple alignment analysis of the PilV and PilW (pilin) proteins indicated that pilV is the adhesin gene while pilW codes for the major protein element of Tfp. The likely function of Tfp is to complete the circuit between the cell surface and Fe(II) oxides. These results indicate that Tfp of A. ferrooxidans might serve as biological nanowires transferring electrons from the surface of Fe(II) oxides to the cell surface. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Earthworm symbiont Verminephrobacter eiseniae mediates natural transformation within the host egg capsules using type IV pili

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    SEANA Kelyn DAVIDSON

    2014-10-01

    Full Text Available The dense microbial communities commonly associated with plants and animals should offer many opportunities for horizontal gene transfer (HGT through described mechanisms of DNA exchange including natural transformation. However, studies of the significance of natural transformation have focused primarily on pathogens. The study presented here demonstrates highly efficient DNA exchange by natural transformation in a common symbiont of earthworms. The obligate bacterial symbiont Verminephrobacter eiseniae is a member of a microbial consortium of the earthworm Eisenia fetida that is transmitted into the egg capsules to colonize the embryonic worms. In the study presented here, by testing for transformants under different conditions in culture, we demonstrate that V. eiseniae can incorporate free DNA from the environment, that competency is regulated by environmental factors, and that it is sequence specific. Mutations in the type IV pili of V. eiseniae resulted in loss of DNA uptake, implicating the type IV pilus (TFP apparatus in DNA uptake. Furthermore, injection of DNA carrying antibiotic-resistance genes into egg capsules resulted in transformants within the capsule, demonstrating the relevance of DNA uptake within the earthworm system. The ability to take up species-specific DNA from the environment may explain the maintenance of the relatively large, intact genome of this long-associated obligate symbiont, and provides a mechanism for acquisition of foreign genes within the earthworm system.

  19. Book review, Ominis e bestias in su campidanu de iossu, Marcello Furio Pili

    Directory of Open Access Journals (Sweden)

    Manuel Graziani

    2011-12-01

    Full Text Available Ciò che ci ha più incuriosito di questa pubblicazione è il sottotitolo “Il rapporto tra uomini e animali nelle attività lavorative del passato e del presente”. L’autore Marcello Furio Pili, pur riconoscendo una sorta di omologazione della società umana a seguito della rivoluzione industriale, parte dal presupposto storico dell’unicità del rapporto con gli animali che da sempre è un tratto distintivo del popolo sardo. La ricerca si concentra su cinque paesi del Basso Campidano: Nuraminis, Monastir, Ussana, San Sperate e Sestu, ognuno trattato in una veste monografica a sé stante ma con la medesima struttura editoriale e contenutistica. Cinque paesi di stampo rurale la cui economia, almeno fino ai primi decenni del ’900, “era fondata essenzialmente sull’utilizzo della terra, agricoltura e allevamento di bestiame quindi, e quasi ogni altra attività ruotava intorno alla sfera del rus, della campagna”. Grande spazio viene dedicato, infatti, agli animali (bovini, equini, caprini, suidi, canidi, felini, leporidi, roditori, uccelli, insetti, ecc. che vengono classificati secondo la tassonomia risalente al Sistema della Natura di Linneo, con ovini e caprini accorpati in un unico paragrafo seguendo la moderna classificazione che li inserisce entrambi nella sottofamiglia Caprinae.Il grande formato del libro (21 × 29 cm e la presenza di numerose foto di animali, vegetazione e, soprattutto, vecchi strumenti di lavoro, rendono ancor più interessante questa ricerca che, pur essendo sostanzialmente di carattere antropologico, culturale e linguistico, è molto centrata sul rapporto uomo-animale: “Il rapporto con gli animali, in un modo o nell’altro, era, per quasi tutti i componenti della comunità, costante, necessario, inevitabile.”.

  20. Serine-rich repeat proteins and pili promote Streptococcus agalactiae colonization of the vaginal tract.

    Science.gov (United States)

    Sheen, Tamsin R; Jimenez, Alyssa; Wang, Nai-Yu; Banerjee, Anirban; van Sorge, Nina M; Doran, Kelly S

    2011-12-01

    Streptococcus agalactiae (group B streptococcus [GBS]) is a Gram-positive bacterium found in the female rectovaginal tract and is capable of producing severe disease in susceptible hosts, including newborns and pregnant women. The vaginal tract is considered a major reservoir for GBS, and maternal vaginal colonization poses a significant risk to the newborn; however, little is known about the specific bacterial factors that promote GBS colonization and persistence in the female reproductive tract. We have developed in vitro models of GBS interaction with the human female cervicovaginal tract using human vaginal and cervical epithelial cell lines. Analysis of isogenic mutant GBS strains deficient in cell surface organelles such as pili and serine-rich repeat (Srr) proteins shows that these factors contribute to host cell attachment. As Srr proteins are heavily glycosylated, we confirmed that carbohydrate moieties contribute to the effective interaction of Srr-1 with vaginal epithelial cells. Antibody inhibition assays identified keratin 4 as a possible host receptor for Srr-1. Our findings were further substantiated in an in vivo mouse model of GBS vaginal colonization, where mice inoculated with an Srr-1-deficient mutant exhibited decreased GBS vaginal persistence compared to those inoculated with the wild-type (WT) parental strain. Furthermore, competition experiments in mice showed that WT GBS exhibited a significant survival advantage over the ΔpilA or Δsrr-1 mutant in the vaginal tract. Our results suggest that these GBS surface proteins contribute to vaginal colonization and may offer new insights into the mechanisms of vaginal niche establishment.

  1. Serine-Rich Repeat Proteins and Pili Promote Streptococcus agalactiae Colonization of the Vaginal Tract ▿

    Science.gov (United States)

    Sheen, Tamsin R.; Jimenez, Alyssa; Wang, Nai-Yu; Banerjee, Anirban; van Sorge, Nina M.; Doran, Kelly S.

    2011-01-01

    Streptococcus agalactiae (group B streptococcus [GBS]) is a Gram-positive bacterium found in the female rectovaginal tract and is capable of producing severe disease in susceptible hosts, including newborns and pregnant women. The vaginal tract is considered a major reservoir for GBS, and maternal vaginal colonization poses a significant risk to the newborn; however, little is known about the specific bacterial factors that promote GBS colonization and persistence in the female reproductive tract. We have developed in vitro models of GBS interaction with the human female cervicovaginal tract using human vaginal and cervical epithelial cell lines. Analysis of isogenic mutant GBS strains deficient in cell surface organelles such as pili and serine-rich repeat (Srr) proteins shows that these factors contribute to host cell attachment. As Srr proteins are heavily glycosylated, we confirmed that carbohydrate moieties contribute to the effective interaction of Srr-1 with vaginal epithelial cells. Antibody inhibition assays identified keratin 4 as a possible host receptor for Srr-1. Our findings were further substantiated in an in vivo mouse model of GBS vaginal colonization, where mice inoculated with an Srr-1-deficient mutant exhibited decreased GBS vaginal persistence compared to those inoculated with the wild-type (WT) parental strain. Furthermore, competition experiments in mice showed that WT GBS exhibited a significant survival advantage over the ΔpilA or Δsrr-1 mutant in the vaginal tract. Our results suggest that these GBS surface proteins contribute to vaginal colonization and may offer new insights into the mechanisms of vaginal niche establishment. PMID:21984789

  2. Type IV pili in Francisella – A virulence trait in an intracellular pathogen

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    Emelie eNäslund Salomonsson

    2011-02-01

    Full Text Available Francisella tularensis is a highly virulent intracellular human pathogen that is capable of rapid proliferation in the infected host. Mutants affected in intracellular survival and growth are highly attenuated which highlights the importance of the intracellular phase of the infection. Genomic analysis has revealed that Francisella encodes all genes required for expression of functional type IV pili (Tfp, and in this focused review we summarise recent findings regarding this system in the pathogenesis of tularemia. Tfp are dynamic adhesive structures that have been identified as major virulence determinants in several human pathogens, but it is not obvious what role these structures could have in an intracellular pathogen like Francisella. In the human pathogenic strains, genes required for secretion and assembly of Tfp and one pilin, PilA, have shown to be required for full virulence. Importantly, specific genetic differences have been identified between the different Francisella subspecies where in the most pathogenic type A variants all genes are intact while several Tfp genes are pseudogenes in the less pathogenic type B strains. This suggests that there has been a selection for expression of Tfp with different properties in the different subspecies. There is also a possibility that the genetic differences reflect adaption to different environmental niches of the subspecies and plays a role in transmission of tularemia. This is also in line with recent findings where Tfp pilins are found to be glycosylated which could reflect a role for Tfp in the environment to promote survival and transmission. We are still far from understanding the role of Tfp in virulence and transmission of tularemia, but with the genomic information and genetic tools available we are in a good position to address these issues in the future.

  3. Twitching motility of bacteria with type-IV pili: Fractal walks, first passage time, and their consequences on microcolonies

    Science.gov (United States)

    Bisht, Konark; Klumpp, Stefan; Banerjee, Varsha; Marathe, Rahul

    2017-11-01

    A human pathogen, Neisseria gonorrhoeae (NG), moves on surfaces by attaching and retracting polymeric structures called Type IV pili. The tug-of-war between the pili results in a two-dimensional stochastic motion called twitching motility. In this paper, with the help of real-time NG trajectories, we develop coarse-grained models for their description. The fractal properties of these trajectories are determined and their influence on first passage time and formation of bacterial microcolonies is studied. Our main observations are as follows: (i) NG performs a fast ballistic walk on small time scales and a slow diffusive walk over long time scales with a long crossover region; (ii) there exists a characteristic persistent length lp*, which yields the fastest growth of bacterial aggregates or biofilms. Our simulations reveal that lp*˜L0.6 , where L ×L is the surface on which the bacteria move; (iii) the morphologies have distinct fractal characteristics as a consequence of the ballistic and diffusive motion of the constituting bacteria.

  4. Binding of CFA/I Pili of Enterotoxigenic Escherichia coli to Asialo-GM1 Is Mediated by the Minor Pilin CfaE.

    Science.gov (United States)

    Madhavan, T P Vipin; Riches, James D; Scanlon, Martin J; Ulett, Glen C; Sakellaris, Harry

    2016-05-01

    CFA/I pili are representatives of a large family of related pili that mediate the adherence of enterotoxigenic Escherichia coli to intestinal epithelial cells. They are assembled via the alternate chaperone-usher pathway and consist of two subunits, CfaB, which makes up the pilus shaft and a single pilus tip-associated subunit, CfaE. The current model of pilus-mediated adherence proposes that CFA/I has two distinct binding activities; the CfaE subunit is responsible for binding to receptors of unknown structure on erythrocyte and intestinal epithelial cell surfaces, while CfaB binds to various glycosphingolipids, including asialo-GM1. In this report, we present two independent lines of evidence that, contrary to the existing model, CfaB does not bind to asialo-GM1 independently of CfaE. Neither purified CfaB subunits nor CfaB assembled into pili bind to asialo-GM1. Instead, we demonstrate that binding activity toward asialo-GM1 resides in CfaE and this is essential for pilus binding to Caco-2 intestinal epithelial cells. We conclude that the binding activities of CFA/I pili for asialo-GM1, erythrocytes, and intestinal cells are inseparable, require the same amino acid residues in CfaE, and therefore depend on the same or very similar binding mechanisms. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  5. Safe sex

    Science.gov (United States)

    ... sex; Sexually transmitted - safe sex; GC - safe sex; Gonorrhea - safe sex; Herpes - safe sex; HIV - safe sex; ... contact. STIs include: Chlamydia Genital herpes Genital warts Gonorrhea Hepatitis HIV HPV Syphilis STIs are also called ...

  6. Modulation of Kingella kingae adherence to human epithelial cells by type IV Pili, capsule, and a novel trimeric autotransporter.

    Science.gov (United States)

    Porsch, Eric A; Kehl-Fie, Thomas E; St Geme, Joseph W

    2012-10-23

    Kingella kingae is an emerging bacterial pathogen that is being recognized increasingly as an important etiology of septic arthritis, osteomyelitis, and bacteremia, especially in young children. Colonization of the posterior pharynx is a key step in the pathogenesis of K. kingae disease. Previous work established that type IV pili are necessary for K. kingae adherence to the respiratory epithelium. In this study, we set out to identify additional factors that influence K. kingae interactions with human epithelial cells. We found that genetic disruption of the gene encoding a predicted trimeric autotransporter protein called Knh (Kingella NhhA homolog) resulted in reduced adherence to human epithelial cells. In addition, we established that K. kingae elaborates a surface-associated polysaccharide capsule that requires a predicted ABC-type transporter export operon called ctrABCD for surface presentation. Furthermore, we discovered that the presence of a surface capsule interferes with Knh-mediated adherence to human epithelial cells by nonpiliated organisms and that maximal adherence in the presence of a capsule requires the predicted type IV pilus retraction machinery, PilT/PilU. On the basis of the data presented here, we propose a novel adherence mechanism that allows K. kingae to adhere efficiently to human epithelial cells while remaining encapsulated and more resistant to immune clearance. Kingella kingae is a Gram-negative bacterium that is being recognized increasingly as a cause of joint and bone infections in young children. The pathogenesis of disease due to K. kingae begins with bacterial colonization of the upper respiratory tract, and previous work established that surface hair-like fibers called type IV pili are necessary for K. kingae adherence to respiratory epithelial cells. In this study, we set out to identify additional factors that influence K. kingae interactions with respiratory epithelial cells. We discovered a novel surface protein called

  7. Lactobacillus rhamnosus GG Outcompetes Enterococcus faecium via Mucus-Binding Pili: Evidence for a Novel and Heterospecific Probiotic Mechanism.

    Science.gov (United States)

    Tytgat, Hanne L P; Douillard, François P; Reunanen, Justus; Rasinkangas, Pia; Hendrickx, Antoni P A; Laine, Pia K; Paulin, Lars; Satokari, Reetta; de Vos, Willem M

    2016-10-01

    Vancomycin-resistant enterococci (VRE) have become a major nosocomial threat. Enterococcus faecium is of special concern, as it can easily acquire new antibiotic resistances and is an excellent colonizer of the human intestinal tract. Several clinical studies have explored the potential use of beneficial bacteria to weed out opportunistic pathogens. Specifically, the widely studied Lactobacillus rhamnosus strain GG has been applied successfully in the context of VRE infections. Here, we provide new insight into the molecular mechanism underlying the effects of this model probiotic on VRE decolonization. Both clinical VRE isolates and L. rhamnosus GG express pili on their cell walls, which are the key modulators of their highly efficient colonization of the intestinal mucosa. We found that one of the VRE pilus clusters shares considerable sequence similarity with the SpaCBA-SrtC1 pilus cluster of L. rhamnosus GG. Remarkable immunological and functional similarities were discovered between the mucus-binding pili of L. rhamnosus GG and those of the clinical E. faecium strain E1165, which was characterized at the genome level. Moreover, E. faecium strain E1165 bound efficiently to mucus, which may be prevented by the presence of the mucus-binding SpaC protein or antibodies against L. rhamnosus GG or SpaC. These results present experimental support for a novel probiotic mechanism, in which the mucus-binding pili of L. rhamnosus GG prevent the binding of a potential pathogen to the host. Hence, we provide a molecular basis for the further exploitation of L. rhamnosus GG and its pilins for prophylaxis and treatment of VRE infections. Concern about vancomycin-resistant Enterococcus faecium causing nosocomial infections is rising globally. The arsenal of antibiotic strategies to treat these infections is nearly exhausted, and hence, new treatment strategies are urgently needed. Here, we provide molecular evidence to underpin reports of the successful clinical application of

  8. Functional genome analysis of Bifidobacterium breve UCC2003 reveals type IVb tight adherence (Tad) pili as an essential and conserved host-colonization factor

    Science.gov (United States)

    O'Connell Motherway, Mary; Zomer, Aldert; Leahy, Sinead C.; Reunanen, Justus; Bottacini, Francesca; Claesson, Marcus J.; O'Brien, Frances; Flynn, Kiera; Casey, Patrick G.; Moreno Munoz, Jose Antonio; Kearney, Breda; Houston, Aileen M.; O'Mahony, Caitlin; Higgins, Des G.; Shanahan, Fergus; Palva, Airi; de Vos, Willem M.; Fitzgerald, Gerald F.; Ventura, Marco; O'Toole, Paul W.; van Sinderen, Douwe

    2011-01-01

    Development of the human gut microbiota commences at birth, with bifidobacteria being among the first colonizers of the sterile newborn gastrointestinal tract. To date, the genetic basis of Bifidobacterium colonization and persistence remains poorly understood. Transcriptome analysis of the Bifidobacterium breve UCC2003 2.42-Mb genome in a murine colonization model revealed differential expression of a type IVb tight adherence (Tad) pilus-encoding gene cluster designated “tad2003.” Mutational analysis demonstrated that the tad2003 gene cluster is essential for efficient in vivo murine gut colonization, and immunogold transmission electron microscopy confirmed the presence of Tad pili at the poles of B. breve UCC2003 cells. Conservation of the Tad pilus-encoding locus among other B. breve strains and among sequenced Bifidobacterium genomes supports the notion of a ubiquitous pili-mediated host colonization and persistence mechanism for bifidobacteria. PMID:21690406

  9. Functional genome analysis of Bifidobacterium breve UCC2003 reveals type IVb tight adherence (Tad) pili as an essential and conserved host-colonization factor.

    Science.gov (United States)

    O'Connell Motherway, Mary; Zomer, Aldert; Leahy, Sinead C; Reunanen, Justus; Bottacini, Francesca; Claesson, Marcus J; O'Brien, Frances; Flynn, Kiera; Casey, Patrick G; Munoz, Jose Antonio Moreno; Kearney, Breda; Houston, Aileen M; O'Mahony, Caitlin; Higgins, Des G; Shanahan, Fergus; Palva, Airi; de Vos, Willem M; Fitzgerald, Gerald F; Ventura, Marco; O'Toole, Paul W; van Sinderen, Douwe

    2011-07-05

    Development of the human gut microbiota commences at birth, with bifidobacteria being among the first colonizers of the sterile newborn gastrointestinal tract. To date, the genetic basis of Bifidobacterium colonization and persistence remains poorly understood. Transcriptome analysis of the Bifidobacterium breve UCC2003 2.42-Mb genome in a murine colonization model revealed differential expression of a type IVb tight adherence (Tad) pilus-encoding gene cluster designated "tad(2003)." Mutational analysis demonstrated that the tad(2003) gene cluster is essential for efficient in vivo murine gut colonization, and immunogold transmission electron microscopy confirmed the presence of Tad pili at the poles of B. breve UCC2003 cells. Conservation of the Tad pilus-encoding locus among other B. breve strains and among sequenced Bifidobacterium genomes supports the notion of a ubiquitous pili-mediated host colonization and persistence mechanism for bifidobacteria.

  10. Pili Annulati Coincident with Alopecia Areata, Autoimmune Thyroid Disease, and Primary IgA Deficiency: Case Report and Considerations on the Literature

    Directory of Open Access Journals (Sweden)

    E. Castelli

    2012-11-01

    Full Text Available Pili annulati is a rare autosomal dominant hair disorder clinically characterized by a pattern of alternating bright and dark bands of the hair, the bright bands appearing dark if observed by transmitted light. This pattern is due to the periodic occurrence of air-filled cavities along the hair cortex which scatter and reflect the light while precluding its transmission. A susceptibility region, including a possibly responsible Frizzled gene, has been mapped to the telomeric region of chromosome 12q, although a specific mutation has not been identified. The condition has sometimes been observed in concurrence with alopecia areata, and in this paper we report a case in whom the concomitant severe alopecia areata was associated with autoimmune thyroid disease and primary IgA deficiency – a quadruple complex which, to our knowledge, has never been previously described. The occurrence of multiple immune disorders in the same patient affected by pili annulati could represent a key to understanding the high prevalence of alopecia areata in this condition. Specifically, in individuals predisposed to autoimmune disease, the molecular alterations that cause the anatomical changes of pili annulati could prompt the immune response against the hair root that underlies alopecia areata.

  11. Phenotypical analysis of the Lactobacillus rhamnosus GG fimbrial spaFED operon: surface expression and functional characterization of recombinant SpaFED pili in Lactococcus lactis.

    Directory of Open Access Journals (Sweden)

    Johanna Rintahaka

    Full Text Available A noticeable genomic feature of many piliated Gram-positive bacterial species is the presence of more than one pilus-encoding operon. Paradigmatically, the gut-adapted Lactobacillus rhamnosus GG strain contains two different fimbrial operons in its genome. However, whereas one of these operons (called spaCBA is encoding for the functionally mucus-/collagen-binding SpaCBA pilus, for the other operon (called spaFED any native expression of the SpaFED-called pili is still the subject of some uncertainty. Irrespective of such considerations, we decided it would be of relevance or interest to decipher the gross structure of this pilus type, and as well assess its functional capabilities for cellular adhesion and immunostimulation. For this, and by following the approach we had used previously to explicate the immuno-properties of SpaCBA pili, we constructed nisin-inducible expression clones producing either wild-type or SpaF pilin-deleted surface-assembled L. rhamnosus GG SpaFED pili on Lactococcus lactis cells. Using these piliated lactococcal constructs, we found that the pilin-polymerized architecture of a recombinant-produced SpaFED pilus coincides with sequence-based functional predictions of the related pilins, and in fact is prototypical of those other sortase-dependent pilus-like structures thus far characterized for piliated Gram-positive bacteria. Moreover, we confirmed that among the different pilin subunits encompassing spaFED operon-encoded pili, the SpaF pilin is a main adhesion determinant, and when present in the assembled structure can mediate pilus binding to mucus, certain extracellular matrix proteins, and different gut epithelial cell lines. However, somewhat unexpectedly, when recombinant SpaFED pili are surface-attached, we found that they could not potentiate the existing lactococcal cell-induced immune responses so elicited from intestinal- and immune-related cells, but rather instead, they could dampen them. Accordingly, we

  12. Phenotypical analysis of the Lactobacillus rhamnosus GG fimbrial spaFED operon: surface expression and functional characterization of recombinant SpaFED pili in Lactococcus lactis.

    Science.gov (United States)

    Rintahaka, Johanna; Yu, Xia; Kant, Ravi; Palva, Airi; von Ossowski, Ingemar

    2014-01-01

    A noticeable genomic feature of many piliated Gram-positive bacterial species is the presence of more than one pilus-encoding operon. Paradigmatically, the gut-adapted Lactobacillus rhamnosus GG strain contains two different fimbrial operons in its genome. However, whereas one of these operons (called spaCBA) is encoding for the functionally mucus-/collagen-binding SpaCBA pilus, for the other operon (called spaFED) any native expression of the SpaFED-called pili is still the subject of some uncertainty. Irrespective of such considerations, we decided it would be of relevance or interest to decipher the gross structure of this pilus type, and as well assess its functional capabilities for cellular adhesion and immunostimulation. For this, and by following the approach we had used previously to explicate the immuno-properties of SpaCBA pili, we constructed nisin-inducible expression clones producing either wild-type or SpaF pilin-deleted surface-assembled L. rhamnosus GG SpaFED pili on Lactococcus lactis cells. Using these piliated lactococcal constructs, we found that the pilin-polymerized architecture of a recombinant-produced SpaFED pilus coincides with sequence-based functional predictions of the related pilins, and in fact is prototypical of those other sortase-dependent pilus-like structures thus far characterized for piliated Gram-positive bacteria. Moreover, we confirmed that among the different pilin subunits encompassing spaFED operon-encoded pili, the SpaF pilin is a main adhesion determinant, and when present in the assembled structure can mediate pilus binding to mucus, certain extracellular matrix proteins, and different gut epithelial cell lines. However, somewhat unexpectedly, when recombinant SpaFED pili are surface-attached, we found that they could not potentiate the existing lactococcal cell-induced immune responses so elicited from intestinal- and immune-related cells, but rather instead, they could dampen them. Accordingly, we have now provided

  13. Type IV Pili are required for virulence, twitching motility, and biofilm formation of acidovorax avenae subsp. Citrulli.

    Science.gov (United States)

    Bahar, Ofir; Goffer, Tal; Burdman, Saul

    2009-08-01

    Acidovorax avenae subsp. citrulli is the causal agent of bacterial fruit blotch (BFB), a threatening disease of watermelon, melon, and other cucurbits. Despite the economic importance of BFB, relatively little is known about basic aspects of the pathogen's biology and the molecular basis of its interaction with host plants. To identify A. avenae subsp. citrulli genes associated with pathogenicity, we generated a transposon (Tn5) mutant library on the background of strain M6, a group I strain of A. avenae subsp. citrulli, and screened it for reduced virulence by seed-transmission assays with melon. Here, we report the identification of a Tn5 mutant with reduced virulence that is impaired in pilM, which encodes a protein involved in assembly of type IV pili (TFP). Further characterization of this mutant revealed that A. avenae subsp. citrulli requires TFP for twitching motility and wild-type levels of biofilm formation. Significant reductions in virulence and biofilm formation as well as abolishment of twitching were also observed in insertional mutants affected in other TFP genes. We also provide the first evidence that group I strains of A. avenae subsp. citrulli can colonize and move through host xylem vessels.

  14. [The detection of occurrence rate of genes coding capability to form pili binding in auto-strains of Escherichia coli].

    Science.gov (United States)

    Ivanova, E I; Popkova, S M; Dzhioev, Iu P; Rakova, E B; Dolgikh, V V; Savel'kaeva, M V; Nemchenko, U M; Bukharova, E V; Serdiuk, L V

    2015-01-01

    E. coli is a commensal of intestine of the vertebrata. The exchange of genetic material of different types of bacteria between themselves and with other representatives of family of Enterobacteriaceae in intestinal ecosystem results in development of types of normal colibacillus with genetic characteristics of pathogenicity that can serve as a theoretical substantiation to attribute such strains to pathobionts. The entero-pathogenic colibacillus continues be an important cause of diarrhea in children in developing countries. The gene responsible for formation of pili binding is a necessary condition for virulence of entero-pathogenic colibacillus. The polymerase chain reaction was applied to examine 316 strains of different types of E. coli (normal, with weak enzyme activity and hemolytic activity) isolated from healthy children and children with functional disorders of gastro-intestinal tract for presence of genes coding capability to form pill binding. The presence of this gene in different biochemical types of E. coli permits to establish the fact of formation of reservoir of pathogenicity in indigent microbiota of intestinal biocenosis.

  15. Sex Therapy

    Science.gov (United States)

    Sex therapy Overview Sex therapy is a type of psychotherapy — a general term for treating mental health problems by talking with a mental health professional. Through sex therapy, you can address concerns about sexual function, ...

  16. Sex Headaches

    Science.gov (United States)

    Sex headaches Overview Sex headaches are brought on by sexual activity — especially an orgasm. You may notice a dull ache in your head ... severe headache just before or during orgasm. Most sex headaches are nothing to worry about. But some ...

  17. Genomic and Functional Characterization of the Unusual pLOCK 0919 Plasmid Harboring the spaCBA Pili Cluster in Lactobacillus casei LOCK 0919

    Science.gov (United States)

    Aleksandrzak-Piekarczyk, Tamara; Koryszewska-Bagińska, Anna; Grynberg, Marcin; Nowak, Adriana; Cukrowska, Bożena; Kozakova, Hana; Bardowski, Jacek

    2016-01-01

    Here, we report the extensive bioinformatic and functional analyses of the unusual pLOCK 0919, a plasmid originating from the probiotic Lactobacillus casei LOCK 0919 strain. This plasmid is atypical because it harbors the spaCBA-srtC gene cluster encoding SpaCBA pili. We show that all other spaCBA-srtC sequences of the Lactobacillus genus that have been previously described and deposited in GenBank are present in the chromosomal DNA. Another important observation for pLOCK 0919 is that the spaCBA-srtC gene cluster and its surrounding genes are highly similar to the respective DNA region that is present in the most well-known and active SpaCBA pili producer, the probiotic Lactobacillus rhamnosus GG strain. Our results demonstrate that the spaCBA-srtC clusters of pLOCK 0919 and L. rhamnosus GG are genealogically similar, located in DNA regions that are rich in transposase genes and are poorly conserved among the publicly available sequences of Lactobacillus sp. In contrast to chromosomally localized pilus gene clusters from L. casei and Lactobacillus paracasei, the plasmidic spaC of L. casei LOCK 0919 is expressed and undergoes a slight glucose-induced repression. Moreover, results of series of in vitro tests demonstrate that L. casei LOCK 0919 has an adhesion potential, which is largely determined by the presence of the pLOCK 0919 plasmid. In particular, the plasmid occurrence positively influenced the hydrophobicity and aggregation abilities of L. casei LOCK 0919. Moreover, in vivo studies indicate that among the three Lactobacillus strains used to colonize the gastrointestinal tract of germ-free mice, already after 2 days of colonization, L. casei LOCK 0919 became the dominant strain and persisted there for at least 48 days. PMID:26637469

  18. Surface Proteome Analysis of a Natural Isolate of Lactococcus lactis Reveals the Presence of Pili Able to Bind Human Intestinal Epithelial Cells*

    Science.gov (United States)

    Meyrand, Mickael; Guillot, Alain; Goin, Mélodie; Furlan, Sylviane; Armalyte, Julija; Kulakauskas, Saulius; Cortes-Perez, Naima G.; Thomas, Ginette; Chat, Sophie; Péchoux, Christine; Dupres, Vincent; Hols, Pascal; Dufrêne, Yves F.; Trugnan, Germain; Chapot-Chartier, Marie-Pierre

    2013-01-01

    Surface proteins of Gram-positive bacteria play crucial roles in bacterial adhesion to host tissues. Regarding commensal or probiotic bacteria, adhesion to intestinal mucosa may promote their persistence in the gastro-intestinal tract and their beneficial effects to the host. In this study, seven Lactococcus lactis strains exhibiting variable surface physico-chemical properties were compared for their adhesion to Caco-2 intestinal epithelial cells. In this test, only one vegetal isolate TIL448 expressed a high-adhesion phenotype. A nonadhesive derivative was obtained by plasmid curing from TIL448, indicating that the adhesion determinants were plasmid-encoded. Surface-exposed proteins in TIL448 were analyzed by a proteomic approach consisting in shaving of the bacterial surface with trypsin and analysis of the released peptides by LC-MS/MS. As the TIL448 complete genome sequence was not available, the tryptic peptides were identified by a mass matching approach against a database including all Lactococcus protein sequences and the sequences deduced from partial DNA sequences of the TIL448 plasmids. Two surface proteins, encoded by plasmids in TIL448, were identified as candidate adhesins, the first one displaying pilin characteristics and the second one containing two mucus-binding domains. Inactivation of the pilin gene abolished adhesion to Caco-2 cells whereas inactivation of the mucus-binding protein gene had no effect on adhesion. The pilin gene is located inside a cluster of four genes encoding two other pilin-like proteins and one class-C sortase. Synthesis of pili was confirmed by immunoblotting detection of high molecular weight forms of pilins associated to the cell wall as well as by electron and atomic force microscopy observations. As a conclusion, surface proteome analysis allowed us to detect pilins at the surface of L. lactis TIL448. Moreover we showed that pili appendages are formed and involved in adhesion to Caco-2 intestinal epithelial cells

  19. Sex ratios

    OpenAIRE

    West, Stuart A; Reece, S E; Sheldon, Ben C

    2002-01-01

    Sex ratio theory attempts to explain variation at all levels (species, population, individual, brood) in the proportion of offspring that are male (the sex ratio). In many cases this work has been extremely successful, providing qualitative and even quantitative explanations of sex ratio variation. However, this is not always the situation, and one of the greatest remaining problems is explaining broad taxonomic patterns. Specifically, why do different organisms show so ...

  20. Creating Sex

    DEFF Research Database (Denmark)

    Cahana, Jonathan

    2016-01-01

    Thomas Laqueur’s influential yet controversial study Making Sex has, in many ways, revolutionized our understanding of sexuality in antiquity. Yet, most of Laqueur’s critics and supporters stressed the one-sex body, while the crux of his argument is the primacy of gender. Moreover, a systematic...

  1. Sex determination

    Indian Academy of Sciences (India)

    The sex-determining system differs considerably among organisms. Even among insect species, the genetic system for sex-determination is highly diversified. In Drosophila melanogaster, somatic sexual differentiation is regulated by a well characterized genetic hierarchy X : A > Sxl > tra/tra2 > dsx and fru. This cascade ...

  2. Neisseria meningitidis differentially controls host cell motility through PilC1 and PilC2 components of type IV Pili.

    Directory of Open Access Journals (Sweden)

    Philippe C Morand

    Full Text Available Neisseria meningitidis is a strictly human pathogen that has two facets since asymptomatic carriage can unpredictably turn into fulminant forms of infection. Meningococcal pathogenesis relies on the ability of the bacteria to break host epithelial or endothelial cellular barriers. Highly restrictive, yet poorly understood, mechanisms allow meningococcal adhesion to cells of only human origin. Adhesion of encapsulated and virulent meningococci to human cells relies on the expression of bacterial type four pili (T4P that trigger intense host cell signalling. Among the components of the meningococcal T4P, the concomitantly expressed PilC1 and PilC2 proteins regulate pili exposure at the bacterial surface, and until now, PilC1 was believed to be specifically responsible for T4P-mediated meningococcal adhesion to human cells. Contrary to previous reports, we show that, like PilC1, the meningococcal PilC2 component is capable of mediating adhesion to human ME180 epithelial cells, with cortical plaque formation and F-actin condensation. However, PilC1 and PilC2 promote different effects on infected cells. Cellular tracking analysis revealed that PilC1-expressing meningococci caused a severe reduction in the motility of infected cells, which was not the case when cells were infected with PilC2-expressing strains. The amount of both total and phosphorylated forms of EGFR was dramatically reduced in cells upon PilC1-mediated infection. In contrast, PilC2-mediated infection did not notably affect the EGFR pathway, and these specificities were shared among unrelated meningococcal strains. These results suggest that meningococci have evolved a highly discriminative tool for differential adhesion in specific microenvironments where different cell types are present. Moreover, the fine-tuning of cellular control through the combined action of two concomitantly expressed, but distinctly regulated, T4P-associated variants of the same molecule (i.e. PilC1 and Pil

  3. Oral sex.

    Science.gov (United States)

    1996-04-05

    The Gay and Lesbian Medical Association urges HIV prevention specialists to regard male-to-male oral-genital sex as a low-risk activity and concentrate instead on the danger of unprotected anal intercourse. According to the association, the confusion and mixed messages surrounding oral sex are harming efforts to encourage gay men to make rational choices about truly risky behavior. The recommendations appear in the association's position paper issued March 19, 1996.

  4. Why Sex?

    DEFF Research Database (Denmark)

    Nielsen, Rasmus

    2006-01-01

    It is assumed that most organisms have sex because the resulting genetic recombination allows Darwinian selection to work better. It is now shown that in water fleas, recombination does lead to fewer deleterious mutations.......It is assumed that most organisms have sex because the resulting genetic recombination allows Darwinian selection to work better. It is now shown that in water fleas, recombination does lead to fewer deleterious mutations....

  5. Comprehensive mutagenesis of the fimS promoter regulatory switch reveals novel regulation of type 1 pili in uropathogenic Escherichia coli.

    Science.gov (United States)

    Zhang, Huibin; Susanto, Teodorus T; Wan, Yue; Chen, Swaine L

    2016-04-12

    Type 1 pili (T1P) are major virulence factors for uropathogenic Escherichia coli (UPEC), which cause both acute and recurrent urinary tract infections. T1P expression therefore is of direct relevance for disease. T1P are phase variable (both piliated and nonpiliated bacteria exist in a clonal population) and are controlled by an invertible DNA switch (fimS), which contains the promoter for the fim operon encoding T1P. Inversion of fimS is stochastic but may be biased by environmental conditions and other signals that ultimately converge at fimS itself. Previous studies of fimS sequences important for T1P phase variation have focused on laboratory-adapted E coli strains and have been limited in the number of mutations or by alteration of the fimS genomic context. We surmounted these limitations by using saturating genomic mutagenesis of fimS coupled with accurate sequencing to detect both mutations and phase status simultaneously. In addition to the sequences known to be important for biasing fimS inversion, our method also identifies a previously unknown pair of 5' UTR inverted repeats that act by altering the relative fimA levels to control phase variation. Thus we have uncovered an additional layer of T1P regulation potentially impacting virulence and the coordinate expression of multiple pilus systems.

  6. Sex. Dev.

    OpenAIRE

    Jakubiczka, S.; Schröder, C.; Ullmann, R.; Volleth, M.; Ledig, S.; Gilberg, E.; Kroisel, P.; P. Wieacker, P.

    2010-01-01

    Campomelic dysplasia (MIM 114290) is a severe malformation syndrome frequently accompanied by male-to-female sex reversal. Causative are mutations within the SOX9 gene on 17q24.3 as well as chromosomal aberrations (translocations, inversions or deletions) in the vicinity of SOX9 . Here, we report on a patient with muscular hypotonia, craniofacial dysmorphism, cleft palate, brachydactyly, malformations of thoracic spine, and gonadal dysgenesis with female external genitalia and müllerian duct ...

  7. When Sex Is Painful

    Science.gov (United States)

    ... AQ FREQUENTLY ASKED QUESTIONS GYNECOLOGIC PROBLEMS FAQ020 When Sex Is Painful • How common is painful sex? • What causes pain during sex? • Where is pain during sex felt? • When should ...

  8. Sex during Pregnancy

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Sex During Pregnancy KidsHealth / For Parents / Sex During Pregnancy ... satisfying and safe sexual relationship during pregnancy. Is Sex During Pregnancy Safe? Sex is considered safe during ...

  9. Sex Education

    Directory of Open Access Journals (Sweden)

    R N Srivastava

    1994-06-01

    Full Text Available Sex, though not everything in life, is a profoundly important aspect of human existence. It has evolved to serve more than reproductive functions; relational and recreational functions having taken precedence over procrea­tional. Sex has come to play a much wider socio-psychological function. Human sexuality is complex and multidimensional. It is subject to influence by multitude of factors often grouped as biological (e.g. genes, hormones, psychological (e.g. fear, anxiety, mood and socio-cultural (e.g. sex roles, values- religious/moral/ethical, customs. It is the interaction and interrelationship of these factors from the time of conception, through intrauterine life, infancy, childhood and adolescence, till adulthood (even later in life that determine the sexual development expressed as sexual attitudes and behaviour of the people. Learning, both social and cognitive, plays a significantly important role in such development. Sexual dysfunctions in men and women, result from factors often categorised as physical or organic and psychological; more often a combination may be involved. Experience has shown that in majority of men and women in India having sexual problems, ignorance misconceptions and prevailing myths are invariably responsible in the causation of Ihese problems. Sexual problems in individual man (e.g. erectile failure and woman (e.g. vaginismus cause anxiety, feelings of frustration, lowered self esteem and symptoms of depression. The condition may also affect the spouse; he/she, as a reaction to the problem in the partner, may develop sexual and psychosocial problems including distressed marital relationship. This may also have influence on general couple relationship, effecting adversely the quality of family life. Modern therapeutic endevours have made it possible now to offer effective therapy to most people who seek help for their sexual problems, thus preventing the consequences on couple relationship. However, there is

  10. SEX EDUCATION

    Directory of Open Access Journals (Sweden)

    R N Srivastava

    1994-06-01

    Full Text Available Sex, though not everything in life, is a profoundly important aspect of human existence. It has evolved to serve more than reproductive functions; relational and recreational functions having taken precedence over procrea­tional. Sex has come to play a much wider socio-psychological function.Human sexuality is complex and multidimensional. It is subject to influence by multitude of factors often grouped as biological (e.g. genes, hormones, psychological (e.g. fear, anxiety, mood and socio-cultural (e.g. sex roles, values- religious/moral/ethical, customs. It is the interaction and interrelationship of these factors from the time of conception, through intrauterine life, infancy, childhood and adolescence, till adulthood (even later in life that determine the sexual development expressed as sexual attitudes and behaviour of the people. Learning, both social and cognitive, plays a significantly important role in such development.Sexual dysfunctions in men and women, result from factors often categorised as physical or organic and psychological; more often a combination may be involved. Experience has shown that in majority of men and women in India having sexual problems, ignorance misconceptions and prevailing myths are invariably responsible in the causation of Ihese problems. Sexual problems in individual man (e.g. erectile failure and woman (e.g. vaginismus cause anxiety, feelings of frustration, lowered self esteem and symptoms of depression. The condition may also affect the spouse; he/she, as a reaction to the problem in the partner, may develop sexual and psychosocial problems including distressed marital relationship. This may also have influence on general couple relationship, effecting adversely the quality of family life.Modern therapeutic endevours have made it possible now to offer effective therapy to most people who seek help for their sexual problems, thus preventing the consequences on couple relationship. However, there is also

  11. Quantitative sexing (Q-Sexing) and relative quantitative sexing (RQ ...

    African Journals Online (AJOL)

    samer

    Key words: Polymerase chain reaction (PCR), quantitative real time polymerase chain reaction (qPCR), quantitative sexing, Siberian tiger. INTRODUCTION. Animal molecular sexing .... 43:3-12. Ellegren H (1996). First gene on the avian W chromosome (CHD) provides a tag for universal sexing of non-ratite birds. Proc.

  12. Sex-linked dominant

    Science.gov (United States)

    Inheritance - sex-linked dominant; Genetics - sex-linked dominant; X-linked dominant; Y-linked dominant ... can be either an autosomal chromosome or a sex chromosome. It also depends on whether the trait ...

  13. Multiple sex partner

    African Journals Online (AJOL)

    User

    intercourse, about 60% reported having a single sexual partner and 40% reported having multiple ... masturbation, start having sex at a younger age, have sex with married people and/or .... sex were considered unacceptable by 89 vs.

  14. Understanding Sex for Sale

    DEFF Research Database (Denmark)

    This book Understanding Sex for Sale: Meanings and Moralities of Sexual Commerce is dedicated to the exploration of the ways in which sex prostitution, sex work or sex for sale are taken for granted by particularly looking at how the relation between sex and money is interpreted and enacted....... This interdisciplinary book aims to understand how prostitution, sex work or sex for sale are defined, delineated, contested and understood in different places and times. The book offers contributions from a number of scholars who, based on their on their own research, discuss on going theoretical issues and analytical...... challenges Some chapters focuses on how prostitution, sex work or sex for sale have been regulated by the authorities and what understandings this regulation builds on. Other chapters investigate the experiences of the sex workers and sex buyers asking how these actors adjust to or resist the categorisation...

  15. Sex Education: Another View

    Science.gov (United States)

    Hamilton, Jennifer

    1977-01-01

    The mother of a 14-year-old mentally retarded boy comments on the viewpoints of Dr. Sol Gordon (a sex education columnist) regarding masturbation, questions on sex, marriage, and the parents' role. (SBH)

  16. Sex in situ

    DEFF Research Database (Denmark)

    Krøgholt, Ida

    2017-01-01

    Sex er en del af vores sociale praksis og centralt for det, vi hver især er. Men bortset fra pornoindustrien, har vi ikke mange muligheder for at få adgang til billeder af sex. Teater Nordkrafts forestilling Sex in situ vil gøre seksuelle billeder til noget, der kan deles, udveksles og tales om, og...

  17. Coeducation and Sex Roles.

    Science.gov (United States)

    Harris, Mary B.

    1986-01-01

    A study of the sex role stereotypes held by 538 first-term Australian university students from single-sex and coeducational high schools is presented. Results suggest that coeducational schooling may have some advantages for fostering interactions with the opposite sex. (MSE)

  18. sex and Cannibalism

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 12. The Secret Sex Lives of Rotifers Sex - sex and Cannibalism. T Ramakrishna Rao. General Article Volume 5 Issue 12 December 2000 pp 41-47. Fulltext. Click here to view fulltext PDF. Permanent link:

  19. A Sex Work Research Symposium: Examining Positionality in Documenting Sex Work and Sex Workers’ Rights

    OpenAIRE

    Megan Lowthers; Magdalena Sabat; Elya M. Durisin; Kamala Kempadoo

    2017-01-01

    Historically, academic literature on sex work has documented the changing debates, policies, and cultural discourse surrounding the sex industry, and their impact on the rights of sex workers worldwide. As sex work scholars look to the future of sex workers’ rights, however, we are also in a critical moment of self-reflection on how sex work scholarship engages with sex worker communities, produces knowledge surrounding sex work, and represents the lived experiences of sex workers’ rights, or...

  20. Neuroprotection of Sex Steroids

    Science.gov (United States)

    Liu, Mingyue; Kelley, Melissa H.; Herson, Paco S.; Hurn, Patricia D.

    2011-01-01

    Sex steroids are essential for reproduction and development in animals and humans, and sex steroids also play an important role in neuroprotection following brain injury. New data indicate that sex-specific responses to brain injury occur at the cellular and molecular levels. This review summarizes the current understanding of neuroprotection by sex steroids, particularly estrogen, androgen, and progesterone, based on both in vitro and in vivo studies. Better understanding of the role of sex steroids under physiological and pathological conditions will help us to develop novel effective therapeutic strategies for brain injury. PMID:20595940

  1. Sex Reversal in Birds.

    Science.gov (United States)

    Major, Andrew T; Smith, Craig A

    2016-01-01

    Sexual differentiation in birds is controlled genetically as in mammals, although the sex chromosomes are different. Males have a ZZ sex chromosome constitution, while females are ZW. Gene(s) on the sex chromosomes must initiate gonadal sex differentiation during embryonic life, inducing paired testes in ZZ individuals and unilateral ovaries in ZW individuals. The traditional view of avian sexual differentiation aligns with that expounded for other vertebrates; upon sexual differentiation, the gonads secrete sex steroid hormones that masculinise or feminise the rest of the body. However, recent studies on naturally occurring or experimentally induced avian sex reversal suggest a significant role for direct genetic factors, in addition to sex hormones, in regulating sexual differentiation of the soma in birds. This review will provide an overview of sex determination in birds and both naturally and experimentally induced sex reversal, with emphasis on the key role of oestrogen. We then consider how recent studies on sex reversal and gynandromorphic birds (half male:half female) are shaping our understanding of sexual differentiation in avians and in vertebrates more broadly. Current evidence shows that sexual differentiation in birds is a mix of direct genetic and hormonal mechanisms. Perturbation of either of these components may lead to sex reversal. © 2016 S. Karger AG, Basel.

  2. Sexing young snowy owls

    Science.gov (United States)

    Seidensticker, M.T.; Holt, D.W.; Detienne, J.; Talbot, S.; Gray, K.

    2011-01-01

    We predicted sex of 140 Snowy Owl (Bubo scandiacus) nestlings out of 34 nests at our Barrow, Alaska, study area to develop a technique for sexing these owls in the field. We primarily sexed young, flightless owls (3844 d old) by quantifying plumage markings on the remiges and tail, predicting sex, and collecting blood samples to test our field predictions using molecular sexing techniques. We categorized and quantified three different plumage markings: two types of bars (defined as markings that touch the rachis) and spots (defined as markings that do not touch the rachis). We predicted sex in the field assuming that males had more spots than bars and females more bars than spots on the remiges and rectrices. Molecular data indicated that we correctly sexed 100% of the nestlings. We modeled the data using random forests and classification trees. Both models indicated that the number and type of markings on the secondary feathers were the most important in classifying nestling sex. The statistical models verified our initial qualitative prediction that males have more spots than bars and females more bars than spots on flight feathers P6P10 for both wings and tail feathers T1 and T2. This study provides researchers with an easily replicable and highly accurate method for sexing young Snowy Owls in the field, which should aid further studies of sex-ratios and sex-related variation in behavior and growth of this circumpolar owl species. ?? 2011 The Raptor Research Foundation, Inc.

  3. Osho - Insights on sex.

    Science.gov (United States)

    Nagaraj, Anil Kumar Mysore

    2013-01-01

    Sex is a mysterious phenomenon, which has puzzled even great sages. Human beings have researched and mastered the biology of sex. But that is not all. Sex needs to be understood from the spiritual perspective too. The vision of Osho is an enlightening experience in this regard. Out of the thousands of lectures, five lectures on sex made Osho most notorious. Born into a Jain family of Madhya Pradesh, Rajneesh, who later wanted himself to be called Osho, is a great master. He has spoken volumes on a wide range of topics ranging from sex to super-consciousness. His contributions in the area of sex are based on the principles of "Tantra" which has its origin from Buddhism. This article focuses on his life and insights on sex, which if understood properly, can be a stepping stone for enlightenment.

  4. Helping Behavior: Effects of Sex and Sex-Typing.

    Science.gov (United States)

    Basow, Susan A.; Crawley, Donna M.

    1982-01-01

    Male and female experimenters requested adult shoppers (N=178) to fill out a questionnaire. Refusal data showed shoppers helping other-sex more than same-sex experimenters. Other results showed a significant three-way interaction among helper and helpee sex and sex-typing and situation sex-typing and that helper sex-typing did not have significant…

  5. Doing gender in sex and sex research.

    Science.gov (United States)

    Vanwesenbeeck, Ine

    2009-12-01

    Gender is central to sexuality, and vice versa, but there are a number of difficulties with the treatment of gender in sex research. Apparently, it is hard to find a balance between two conflicting needs. First, obviously, it is necessary to make distinctions between women and men, for political as well as research-technical and theoretical reasons. A second requirement, at odds with the first one, is the necessity to understand gender and its relation to sexuality and the body as much more complex than simplistically referring to two sets of individuals. This is all the more necessary when one realizes the possible drawbacks of exaggerating the differences between the sexes (in particular when they are biologically explained), because of stereotyping, stigmatizing, and expectancy confirmatory processes. This essay identifies and discusses 10 difficulties in the treatment of gender in sex research, reflects on their origins, and reviews theory and evidence with the aim to (1) consider the relative strength of gender/sex as an explanatory variable compared to other factors and processes explaining differences between men and women on a number of sexual aspects, (2) inform an understanding of gender and its relation to sexuality as an ongoing, open-ended, multi-determined, situated, interactional process, with the body as a third player, and (3) argue in favor of a nuanced, well-balanced treatment of gender in sex research.

  6. Sex reversal in vertebrates

    OpenAIRE

    2016-01-01

    This special topic issue of Sexual Development gives an overview of sex reversal in vertebrates, from fishes naturally changing their sex, to rodents escaping the mammalian SRY-determining system. It offers eight up-to-date reviews on specific subjects in sex reversal, considering fishes, amphibians, reptiles, birds, marsupials, and placental mammals, including humans. The broad scope of represented animals makes this ideal for students and researchers, especially those interested in the...

  7. Sex tourism in Thailand.

    Science.gov (United States)

    Van Kerkwijk, C

    1992-01-01

    Many foreigners visit Thailand in search of sex. While long-distance tourism was long enjoyed by members of more privileged social classes, even the lower economical classes of Japan, Malaysia, Europe, America, and Australia can now afford to travel over long distances. This relatively new breed of tourist is more likely to be of lower socioeconomic and educational status and less likely to use condoms when having sex. An estimated 30,000 sex workers are active in Bangkok, of whom 7000/10,000 are females who work specifically in the tourism sector. 1/2-1/3 of the 600 commercial sex establishments in the city are visited by foreigners. Phuket, Pattaya, Koh Samui, and Chiangmai are also well-frequented by sex tourists. Overall, a large, diverse, inexpensive, and accessible commercial sex market exists in Thailand. One may meet sex workers quasi-ubiquitously and be assured to find someone capable of meeting one's sexual needs. With these attributes, Thailand strongly attracts tourists in search of sex. A certain degree of recklessness also prevails among those on vacation. Away from the peers and social mores of their native lands, tourists may engage in sexually activities without criticism. Likewise, Thai sex workers who cater to foreigners, especially females, enjoy more freedom and control in sexual relations than their peers who work among nationals. Neither single nor married women in Thailand are allowed much sexual freedom and are traditionally expected to be obliging docile, and submissive. The greater than normal personal latitude enjoyed by both sex worker and foreigner lead to more negotiation on condom use and overall lower use. As such, Thailand's commercial sex market with foreigners' involvement therein threatens to spread HIV to many other countries throughout the world.

  8. The evolution of sex ratios and sex-determining systems

    NARCIS (Netherlands)

    Uller, Tobias; Pen, Ido; Wapstra, Erik; Beukeboom, Leo W.; Komdeur, Jan

    Sex determination is a fundamental process governed by diverse mechanisms. Sex ratio selection is commonly implicated in the evolution of sex-determining systems, although formal models are rare. Here, we argue that, although sex ratio selection can induce shifts in sex determination, genomic

  9. Sex Determination, Sex Ratios, and Genetic Conflict

    NARCIS (Netherlands)

    Werren, John H.; Beukeboom, Leo W.

    1998-01-01

    Genetic mechanisms of sex determination are unexpectedly diverse and change rapidly during evolution. We review the role of genetic conflict as the driving force behind this diversity and turnover. Genetic conflict occurs when different components of a genetic system are subject to selection in

  10. Insects and sex

    NARCIS (Netherlands)

    Beukeboom, Leo

    2005-01-01

    Most organisms reproduce sexually, but the evolution of sexual reproduction is not yet well understood. Sexual reproduction leads to new variation and adaptations to the environment, but sex is also costly. Some insects reproduce without sex through parthenogenesis or paedogenesis. Almost all sexual

  11. Sex Away from Home

    Science.gov (United States)

    Greenwald, Harold

    1971-01-01

    The reasons why people who are normally truthful to their spouses engage in sex away from home are discussed. These reasons can include loneliness, ego building or the opportunity to have homosexual relations. Sex away from home is likely to increase since the number of people traveling is increasing. (Author/CG)

  12. Single-Sex Classrooms

    Science.gov (United States)

    Protheroe, Nancy

    2009-01-01

    Although single-sex education was once the norm in the U.S., the practice has largely been confined to private schools for more than a century. However, with the introduction of the final version of the U.S. Department of Education's so-called single-sex regulations in 2006, public schools were allowed greater flexibility to offer single-sex…

  13. Sex Education Materials.

    Science.gov (United States)

    Singer-Magdoff, Laura

    1969-01-01

    After briefly discussing the philosophy of sex education and appraising generally the nature of the instructional methods and materials currently in use in the schools, the author provides brief but incisive reviews of a number of films, filmstrips, and other instructional materials dealing with sex. The reviews are continued in the succeeding…

  14. Sex: a sensitive issue.

    Science.gov (United States)

    1997-01-01

    Health care workers and educators may need to improve their skills in discussing sensitive issues in order to elicit and understand what influences people's attitudes toward sex. While the health worker may be bent upon preventing HIV infection, advising on family planning, or teaching youth about sexual relationships, his or her audience may have other priorities. A good counselor/teacher must learn what people's concerns are and discuss sexual health within that context. It can be difficult talking about sex because sex is a private concern and many people are embarrassed discussing it. Even sex partners often find it difficult to talk to each other about sex. Appropriate communication techniques vary depending upon the situation. It depends upon whether one is addressing people on an individual basis or in groups, which people are being addressed, which organization one is representing, and what one's role is. Good communication is a two-way sharing of information. The different stages of life, common beliefs and myths, culture and religion, relationships between men and women, reasons for having sex, and sex practices are discussed.

  15. Making Healthy Decisions About Sex

    Science.gov (United States)

    ... For Teens: How to Make Healthy Decisions About Sex Page Content Article Body Before you decide to ... alcohol or use drugs. Are You Ready for Sex? Sex can change your life and relationships. Having ...

  16. Dyspareunia: Painful Sex for Women

    Science.gov (United States)

    ... Safety Injury Rehabilitation Emotional Well-Being Mental Health Sex and Birth Control Sex and Sexuality Birth Control Family Health Infants and ... Share Print What is dyspareunia? Dyspareunia is painful sex for women. Also, it causes pain during tampon ...

  17. Hepatitis C: Sex and Sexuality

    Science.gov (United States)

    ... with Hepatitis » Sex and Sexuality: Entire Lesson Viral Hepatitis Menu Menu Viral Hepatitis Viral Hepatitis Home For ... hepatitis C virus through sex. Can you pass hepatitis C to a sex partner? Yes, but it ...

  18. Sex education in Portugal.

    Science.gov (United States)

    Frade, A; Vilar, D

    1991-05-01

    The article on sex education in Portugal covers background, the educational system, the clashes of the 1960's over sex education, the Committee for the Study of Sexuality and Education (CSSE), the policies, politics and social movements during the period 1974 - 1984, the discussions in Parliament, the 1988 Reform of the Educational System, the Family Planning Association (FPA) and sex education, and the future role of the FPA. It was not until the institution of the multiparity parliamentary system in 1974 that discussing social and political changes was possible, culminating in 1984 with new legislation on abortion, family planning, and sex education. School reform came in 1987/8 with the Ministry of Education primarily responsible for curricula. The 1960's brought with it the influence of the Catholic Church. Change came in the form of progressivism among Catholics who replaced dogma with dialogue and listening. Sex education was considered as preparation for marriage, but masturbation, contraception, and prostitution were also discussed. In addition, the founder of FPA chaired the CSSE in 1971 and opened up debate on sex issues and drafted a bill to establish co-education in Portuguese schools. The revolution of 1974 brought an end to censorship and brought forth a policy of developing family planning. Changed in the Family Code gave women greater equality. UNFPA supported teacher training in non-sexist education. With human reproduction included in the natural sciences, there was still no school sex education policy and contraception was only sometimes represented in the biology curriculum. The focus of FPA was on contraception and abortion. Finally in the 1980's, the first sex education programs were developed for out-of-school youth. Even though in the 1970's there were leftists groups promoting sex education, it took leftist parliamentary power to get legislation on sex education in the schools adopted. The Ministry of Education however was pressured by the

  19. Sex, Deportation and Rescue

    DEFF Research Database (Denmark)

    Plambech, Sine

    2017-01-01

    recirculating the claim that human trafficking is the “third largest” criminal economy after drugs and weapons. Based on ethnographic fieldwork among Nigerian sex worker migrants conducted in Benin City, Nigeria, in 2011 and 2012, this study brings together four otherwise isolated migration economies......This contribution explores the economies interlinked by the migration of Nigerian women sex workers. The literature and politics of sex work migration and human trafficking economies are commonly relegated to the realm that focuses on profits for criminal networks and pimps, in particular...... – facilitation, remittances, deportation, and rescue – and suggests that we have to examine multiple sites and relink these in order to more fully understand the complexity of sex work migration. Drawing upon literature within transnational feminist analysis, critical human trafficking studies, and migration...

  20. Commentary Sex determination

    Indian Academy of Sciences (India)

    PRAKASH KUMAR G

    2008-01-31

    Jan 31, 2008 ... years old (Charnier 1966 reported it in an African agamid lizard), although it was ... people's attention in Susumu Ohno's now famous book on .... If they do enhance male and female fitness, sex chromosomes would then be.

  1. Commentary Sex determination

    Indian Academy of Sciences (India)

    PRAKASH KUMAR G

    2008-01-31

    ZW is reserved for female heterogamety.) The Radder et al study used lab incubation regimes that mimic temperature profiles of cool natural nests, so temperature probably determines sex at least occasionally in nature.

  2. Female Sex Tourism

    OpenAIRE

    Mc Intyre, Maria Kleivan

    2017-01-01

    ABSTRACT This project explores the phenomenon of North American and Western European women, who travel to the Global South and engage in sexual encounters with the local men. This project has positioned itself as a postcolonial critique, arguing that female sex tourism is a form of neocolonialism. It has also investigated the term romance tourism, where it has found that as a result of essentialist gender stereotyping, the female version of sex tourism has been titled ‘romance tourism’. The p...

  3. Sex and Horror

    OpenAIRE

    Jones, Steve

    2017-01-01

    The combination of sex and horror may be disquieting to many, but the two are natural (if perhaps gruesome) bedfellows. In fact, sex and horror coincide with such regularity in contemporary horror fiction that the two concepts appear to be at least partially intertwined. The sex–horror relationship is sometimes connotative rather than overt; examples of this relationship range from the seduction overtones of 'Nosferatu' and the juxtaposition of nudity and horror promised by European exploitat...

  4. AIDS and sex tourism.

    Science.gov (United States)

    Herold, E S; Van Kerkwijk, C

    1992-01-01

    Tourists traveling internationally lower their inhibitions and take greater risks than they would typically in their home cultures. Loneliness, boredom, and a sense of freedom contribute to this behavioral change. Some tourists travel internationally in search of sexual gratification. This motivation may be actively conscious or subconscious to the traveler. Billed as romantic with great natural beauty, Thailand, the Philippines, Brazil, the Dominican Republic, and Kenya are popular destinations of tourists seeking sex. The Netherlands and countries in eastern Europe are also popular. With most initial cases of HIV infection in Europe having histories of international travel, mass tourism is a major factor in the international transmission of AIDS. While abroad, tourists have sex with casual partners, sex workers, and/or other tourists. Far from all tourists, however, carry and consistently use condoms with these partners. One study found female and non white travelers to be less likely than Whites and males to carry condoms. The risk of HIV infection increases in circumstances where condoms are not readily available in the host country and/or are of poor quality. Regarding actual condom use, a study found only 34% of sex tourists from Switzerland to consistently use condoms while abroad. 28% of men in an STD clinic in Melbourne, Australia, reported consistent condom use in sexual relations while traveling in Asia; STDs were identified in 73% of men examined. The few studies of tourists suggest that a significant proportion engage in risky behavior while traveling. HIV prevalence is rapidly increasing in countries known as destinations for sex tourism. High infection rates are especially evident among teenage sex workers in Thailand. Simply documenting the prevalence of risky behavior among sex tourists will not suffice. More research is needed on travelers and AIDS with particular attention upon the motivating factors supporting persistent high-risk behavior.

  5. Teleology and Defining Sex.

    Science.gov (United States)

    Gamble, Nathan K; Pruski, Michal

    2018-07-01

    Disorders of sexual differentiation lead to what is often referred to as an intersex state. This state has medical, as well as some legal, recognition. Nevertheless, the question remains whether intersex persons occupy a state in between maleness and femaleness or whether they are truly men or women. To answer this question, another important conundrum needs to be first solved: what defines sex? The answer seems rather simple to most people, yet when morphology does not coincide with haplotypes, and genetics might not correlate with physiology the issue becomes more complex. This paper tackles both issues by establishing where the essence of sex is located and by superimposing that framework onto the issue of the intersex. This is achieved through giving due consideration to the biology of sexual development, as well as through the use of a teleological framework of the meaning of sex. Using a range of examples, the paper establishes that sex cannot be pinpointed to one biological variable but is rather determined by how the totality of one's biology is oriented towards biological reproduction. A brief consideration is also given to the way this situation could be comprehended from a Christian understanding of sex and suffering.

  6. Same sex families and children

    OpenAIRE

    Mršević Zorica

    2009-01-01

    Introduction comprises the information on two main forms of same sex families, civic partnership (same sex partnership) and same sex marriage. Countries and various status modalities of legal regulations are mentioned. The main part of the text is dedicated to presentation of the findings of the most recent research on various aspects regarding children of same sex partnerships. It comprises presentations grouped in four main chapters: acceptance of same sex partnerships, acceptance of legal ...

  7. Sex Hormones and Tendon

    DEFF Research Database (Denmark)

    Hansen, Mette; Kjaer, Michael

    2016-01-01

    The risk of overuse and traumatic tendon and ligament injuries differ between women and men. Part of this gender difference in injury risk is probably explained by sex hormonal differences which are specifically distinct during the sexual maturation in the teenage years and during young adulthood....... The effects of the separate sex hormones are not fully elucidated. However, in women, the presence of estrogen in contrast to very low estrogen levels may be beneficial during regular loading of the tissue or during recovering after an injury, as estrogen can enhance tendon collagen synthesis rate. Yet...... has also been linked to a reduced responsiveness to relaxin. The present chapter will focus on sex difference in tendon injury risk, tendon morphology and tendon collagen turnover, but also on the specific effects of estrogen and androgens....

  8. Sex Disparities in Stroke

    DEFF Research Database (Denmark)

    Dehlendorff, Christian; Andersen, Klaus Kaae; Olsen, Tom Skyhøj

    2015-01-01

    between 2003 and 2012 (N=79 617), and the Danish Register of Causes of Death. Information was available on age, sex, marital status, stroke severity, stroke subtype, socioeconomic status, and cardiovascular risk profile. We studied only deaths due to the index stroke, with the assumption that death.......5%) or 1 month (6.9%), respectively. After the age of 60 years, women had more severe strokes than men. Up to ages in the mid-60s, no difference in the risk of death from stroke was seen between the 2 sexes. For people aged >65 years, however, the risk gradually became greater in men than in women...

  9. Sex steroids and neurogenesis.

    Science.gov (United States)

    Heberden, Christine

    2017-10-01

    The brain has long been known as a dimorphic organ and as a target of sex steroids. It is also a site for their synthesis. Sex steroids in numerous ways can modify cerebral physiology, and along with many processes adult neurogenesis is also modulated by sex steroids. This review will focus on the effects of the main steroids, estrogens, androgens and progestogens, and unveil some aspects of their partly disclosed mechanisms of actions. Gonadal steroids act on different steps of neurogenesis: cell proliferation seems to be increased by estrogens only, while androgens and progestogens favor neuronal renewal by increasing cell survival; differentiation is a common target. Aging is characterized by a cognitive deficiency, paralleled by a decrease in the rate of neuronal renewal and in the levels of circulating gonadal hormones. Therefore, the effects of gonadal hormones on the aging brain are important to consider. The review will also be expanded to related molecules which are agonists to the nuclear receptors. Sex steroids can modify adult neuronal renewal and the extensive knowledge of their actions on neurogenesis is essential, as it can be a leading pathway to therapeutic perspectives. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. How Sex Attitudes Develop

    Science.gov (United States)

    Arnstein, Helene S.

    1976-01-01

    Excerpt from "The Roots of Love" (Helene S. Arnstein, 1975). Book is concerned with feelings that are part of child's developmental stages. Included in excerpt are: genital self-discovery, masturbation, discovery of sex differences, and birth fantasies. Stresses importance of parent's feelings which are communicated to child.

  11. Sex differences in addiction.

    Science.gov (United States)

    Becker, Jill B

    2016-12-01

    Women exhibit more rapid escalation from casual drug taking to addiction, exhibit a greater withdrawal response with abstinence, and tend to exhibit greater vulnerability than men in terms of treatment outcome. In rodents, short-term estradiol intake in female rats enhances acquisition and escalation of drug taking, motivation for drugs of abuse, and relapse-like behaviors. There is also a sex difference in the dopamine response in the nucleus accumbens. Ovariectomized female rats exhibit a smaller initial dopamine increase after cocaine treatment than castrated males. Estradiol treatment of ovariectomized female rats enhances stimulated dopamine release in the dorsolateral striatum, but not in the nucleus accumbens, resulting in a sex difference in the balance between these two dopaminergic projections. In the situation where drug-taking behavior becomes habitual, dopamine release has been reported to be enhanced in the dorsolateral striatum and attenuated in the nucleus accumbens. The sex difference in the balance between these neural systems is proposed to underlie sex differences in addiction.

  12. Battle of the Sexes

    NARCIS (Netherlands)

    Bulte, E.H.; Tu, Q.; List, J.

    2015-01-01

    A vibrant literature has emerged that explores the economic implications of the sex ratio (the ratio of men to women in the population), including changes in fertility rates, educational outcomes, labor supply, and household purchases. Previous empirical efforts, however, have paid less attention to

  13. Sex education and ideals

    NARCIS (Netherlands)

    de Ruyter, D.J.; Spiecker, B.

    2008-01-01

    This article argues that sex education should include sexual ideals. Sexual ideals are divided into sexual ideals in the strict sense and sexual ideals in the broad sense. It is argued that ideals that refer to the context that is deemed to be most ideal for the gratification of sexual ideals in the

  14. Sex education in Cyprus.

    Science.gov (United States)

    Patsalides, N

    1991-05-01

    The objective of educating people on family planning and sexuality issues has been carried forth by the Family Planning Association of Cyprus (FPAC) since 1971. The promotion of sex education in schools has generated respect for their expertise. Sex education has reached the agenda of the General Assembly of Parliament only to be postponed due to the April 1991 end of term dismissal. A newly elected Parliament are not expected to act immediately. The Ministry of Education Committee on Health Education has been actively counseled since 1974, and most recently in their examination of the possibilities of school sex education and training of high school teachers. The Ministry of Education has authority over primary and secondary education, which is compulsory up to 3 years of secondary education. The approach of FPAC has been to work with parents first in education lectures at various well publicized locations. The agenda was to inform about FPAC, explain the purpose and meaning of sex education, and show the Merry-Go-Round educational film followed by a question and answer session. Eventually, presentations involved children with parent observation. In 1977, authorization from the Ministry of Education gave official approval to FPAC, but not on school premises. FPAC went directly to headmasters and gained support in primary schools to organize sessions on school premises, which successfully involved many primary schools even in the much needed rural areas. Home Economics and Child Care, offered in the 5th and 6th grades was the only vehicle for gaining permission to enter secondary schools. In Larnaca, secondary school headmasters at the 3rd and 6th grade levels permitted invitations which requested parental permission. Lecture topics on human reproduction, sex roles, and disease and contraception were also provided in a follow-up letter. Higher education levels were involved through youth clubs and evening lectures. In 1988, FPAC urged the Director General of the

  15. Sex and life expectancy.

    Science.gov (United States)

    Seifarth, Joshua E; McGowan, Cheri L; Milne, Kevin J

    2012-12-01

    A sexual dimorphism in human life expectancy has existed in almost every country for as long as records have been kept. Although human life expectancy has increased each year, females still live longer, on average, than males. Undoubtedly, the reasons for the sex gap in life expectancy are multifaceted, and it has been discussed from both sociological and biological perspectives. However, even if biological factors make up only a small percentage of the determinants of the sex difference in this phenomenon, parity in average life expectancy should not be anticipated. The aim of this review is to highlight biological mechanisms that may underlie the sexual dimorphism in life expectancy. Using PubMed, ISI Web of Knowledge, and Google Scholar, as well as cited and citing reference histories of articles through August 2012, English-language articles were identified, read, and synthesized into categories that could account for biological sex differences in human life expectancy. The examination of biological mechanisms accounting for the female-based advantage in human life expectancy has been an active area of inquiry; however, it is still difficult to prove the relative importance of any 1 factor. Nonetheless, biological differences between the sexes do exist and include differences in genetic and physiological factors such as progressive skewing of X chromosome inactivation, telomere attrition, mitochondrial inheritance, hormonal and cellular responses to stress, immune function, and metabolic substrate handling among others. These factors may account for at least a part of the female advantage in human life expectancy. Despite noted gaps in sex equality, higher body fat percentages and lower physical activity levels globally at all ages, a sex-based gap in life expectancy exists in nearly every country for which data exist. There are several biological mechanisms that may contribute to explaining why females live longer than men on average, but the complexity of the

  16. Disestablishing Sex: The Case for Released-Time Sex Education

    Science.gov (United States)

    Glanzer, Perry L.

    2011-01-01

    Allowing nonschool organizations to provide sex education in a released-time format would disestablish state-funded sex education and give families a choice in the sex education that would be provided for their children. Released-time programs, as originally conceived and currently practiced, allow students to be released for a period of time…

  17. Sex identification of Nigerian indigenous chicks using Auto-sexing ...

    African Journals Online (AJOL)

    Sexing has been a challenging task in Nigerian indigenous chickens due to the monomorphism of chicks which makes it impossible to distinguish the male from the female until eight weeks. . Therefore, this study was carried out to determine the sex of Nigerian indigenous chicks using the common auto-sexing methods.

  18. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries ... Coping with a New Injury Robin Dorman, PsyD Sex and Fertility After Spinal Cord Injury Diane M. ...

  19. Sex and Fertility After SCI

    Science.gov (United States)

    ... Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries ... Coping with a New Injury Robin Dorman, PsyD Sex and Fertility After Spinal Cord Injury Diane M. ...

  20. Low Sex Drive in Women

    Science.gov (United States)

    Low sex drive in women Overview Women's sexual desires naturally fluctuate over the years. Highs and lows commonly coincide ... used for mood disorders also can cause low sex drive in women. If your lack of interest ...

  1. SHBG (Sex Hormone Binding Globulin)

    Science.gov (United States)

    ... Links Patient Resources For Health Professionals Subscribe Search Sex Hormone Binding Globulin (SHBG) Send Us Your Feedback ... As Testosterone-estrogen Binding Globulin TeBG Formal Name Sex Hormone Binding Globulin This article was last reviewed ...

  2. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord ... a New Injury Robin Dorman, PsyD Sex and Fertility After Spinal Cord Injury Diane M. Rowles, MS, ...

  3. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... sex after a spinal cord injury? play_arrow Can men and women still have sex after a ... menstruation after a spinal cord injury? play_arrow Can women still get pregnant after a spinal cord ...

  4. Hypnotic Psychotherapy with Sex Offenders

    Science.gov (United States)

    Moseley, Sullivan; Briggs, Wanda P.; Magnus, Virginia

    2005-01-01

    The authors review the literature on the prevalence of sex offenders; multiple treatment modalities; and implications of the use of hypnotic psychotherapy, coupled with cognitive behavioral treatment programs, for treating sex offenders. (Contains 2 tables.)

  5. Sex Education with Young Children.

    Science.gov (United States)

    Koblinsky, Sally; And Others

    1980-01-01

    Discusses guidelines (developed by the Oregon State University Early Childhood Sex Education Project) for developing teacher-parent cooperation in providing sex education to young children. The guidelines concern how to talk about body differences and body functions; how to deal with masturbation, sex play and obscene language; and how to involve…

  6. YY Sex: a Polar Candidate

    Science.gov (United States)

    Gabdeev, M. M.; Shimanskiy, V. V.; Borisov, N. V.; Tazieva, Z. R.

    2017-06-01

    We present spectroscopic investigations of a cataclysmic variable star, YY Sex. There are some uncertainties in the classification of this object. We calculate Doppler maps for Hβ and HeII λ4686Å and show that there is no sign of disk accretion in YY Sex. Consequently, we conclude that YY Sex is a polar.

  7. Sex Education: Challenges and Choices

    Science.gov (United States)

    MacKenzie, Alison; Hedge, Nicki; Enslin, Penny

    2017-01-01

    Noting public concern about sexual exploitation, abuse and sexualisation, we argue that sex education in the UK needs revision. Choice is a feature of current sex education policy and, acknowledging that choice can be problematic, we defend its place in an approach to sex education premised on informed deliberation, relational autonomy, a…

  8. Sex Stereotyping Hurts All Kids.

    Science.gov (United States)

    Cutright, Melitta J.

    1991-01-01

    Sex stereotyping (raising boys and girls to be different because of their sex) begins at birth. The article reviews studies detailing sex stereotyping practices and offers suggestions on what parents can do to avoid them. A list of suggestions for raising children in a nonsexist way is included. (SM)

  9. The many costs of sex.

    Science.gov (United States)

    Lehtonen, Jussi; Jennions, Michael D; Kokko, Hanna

    2012-03-01

    Explaining the evolution of sex is challenging for biologists. A 'twofold cost' compared with asexual reproduction is often quoted. If a cost of this magnitude exists, the benefits of sex must be large for it to have evolved and be maintained. Focusing on benefits can be misleading, as this sidelines important questions about the cost of sex: what is the source of the twofold cost: males, genome dilution or both? Does the cost deviate from twofold? What other factors make sex costly? How should the costs of sex be empirically measured? The total cost of sex and how it varies in different contexts must be known to determine the benefits needed to account for the origin and maintenance of sex. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Sex Differences in HIV Infection.

    Science.gov (United States)

    Scully, Eileen P

    2018-04-01

    This review will outline the multilevel effects of biological sex on HIV acquisition, pathogenesis, treatment response, and prospects for cure. Potential mechanisms will be discussed along with future research directions. HIV acquisition risk is modified by sex hormones and the vaginal microbiome, with the latter acting through both inflammation and local metabolism of pre-exposure prophylaxis drugs. Female sex associates with enhanced risk for non-AIDS morbidities including cardiovascular and cerebrovascular disease, suggesting different inflammatory profiles in men and women. Data from research on HIV cure points to sex differences in viral reservoir dynamics and a direct role for sex hormones in latency maintenance. Biological sex remains an important variable in determining the risk of HIV infection and subsequent viral pathogenesis, and emerging data suggest sex differences relevant to curative interventions. Recruitment of women in HIV clinical research is a pathway to both optimize care for women and to identify novel therapeutics for use in both men and women.

  11. Adolescents' reported consequences of having oral sex versus vaginal sex.

    Science.gov (United States)

    Brady, Sonya S; Halpern-Felsher, Bonnie L

    2007-02-01

    The present study examined whether adolescents' initial consequences of sexual activity differ according to type of sexual activity and gender. Surveys were administered to 618 adolescents recruited from 2 public high schools in the autumn of ninth grade (2002) and at 6-month intervals until the spring of tenth grade (2004). Analyses were limited to the 275 adolescents (44%) who reported engaging in oral sex and/or vaginal sex at any assessment. Participants were 14 years of age at study entry, 56% female, and of diverse socioeconomic and ethnic backgrounds. In comparison with adolescents who engaged in oral sex and/or vaginal sex, adolescents who engaged only in oral sex were less likely to report experiencing a pregnancy or sexually transmitted infection, feeling guilty or used, having their relationship become worse, and getting into trouble with their parents as a result of sex. Adolescents who engaged only in oral sex were also less likely to report experiencing pleasure, feeling good about themselves, and having their relationship become better as a result of sex. Boys were more likely than girls to report feeling good about themselves, experiencing popularity, and experiencing a pregnancy or sexually transmitted infection as a result of sex, whereas girls were more likely than boys to report feeling bad about themselves and feeling used. Adolescents experience a range of social and emotional consequences after having sex. Our findings have implications for clinical practice and public health campaigns targeted toward youth.

  12. Sex Determination, Sex Chromosomes, and Karyotype Evolution in Insects.

    Science.gov (United States)

    Blackmon, Heath; Ross, Laura; Bachtrog, Doris

    2017-01-01

    Insects harbor a tremendous diversity of sex determining mechanisms both within and between groups. For example, in some orders such as Hymenoptera, all members are haplodiploid, whereas Diptera contain species with homomorphic as well as male and female heterogametic sex chromosome systems or paternal genome elimination. We have established a large database on karyotypes and sex chromosomes in insects, containing information on over 13000 species covering 29 orders of insects. This database constitutes a unique starting point to report phylogenetic patterns on the distribution of sex determination mechanisms, sex chromosomes, and karyotypes among insects and allows us to test general theories on the evolutionary dynamics of karyotypes, sex chromosomes, and sex determination systems in a comparative framework. Phylogenetic analysis reveals that male heterogamety is the ancestral mode of sex determination in insects, and transitions to female heterogamety are extremely rare. Many insect orders harbor species with complex sex chromosomes, and gains and losses of the sex-limited chromosome are frequent in some groups. Haplodiploidy originated several times within insects, and parthenogenesis is rare but evolves frequently. Providing a single source to electronically access data previously distributed among more than 500 articles and books will not only accelerate analyses of the assembled data, but also provide a unique resource to guide research on which taxa are likely to be informative to address specific questions, for example, for genome sequencing projects or large-scale comparative studies. © The American Genetic Association 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Sex selection and restricting abortion and sex determination.

    Science.gov (United States)

    Zilberberg, Julie

    2007-11-01

    Sex selection in India and China is fostered by a limiting social structure that disallows women from performing the roles that men perform, and relegates women to a lower status level. Individual parents and individual families benefit concretely from having a son born into the family, while society, and girls and women as a group, are harmed by the widespread practice of sex selection. Sex selection reinforces oppression of women and girls. Sex selection is best addressed by ameliorating the situations of women and girls, increasing their autonomy, and elevating their status in society. One might argue that restricting or prohibiting abortion, prohibiting sex selection, and prohibiting sex determination would eliminate sex selective abortion. But this decreases women's autonomy rather than increases it. Such practices will turn underground. Sex selective infanticide, and slower death by long term neglect, could increase. If abortion is restricted, the burden is placed on women seeking abortions to show that they have a legally acceptable or legitimate reason for a desired abortion, and this seriously limits women's autonomy. Instead of restricting abortion, banning sex selection, and sex determination, it is better to address the practice of sex selection by elevating the status of women and empowering women so that giving birth to a girl is a real and positive option, instead of a detriment to the parents and family as it is currently. But, if a ban on sex selective abortion or a ban on sex determination is indeed instituted, then wider social change promoting women's status in society should be instituted simultaneously.

  14. Talking to Your Kids about Sex

    Science.gov (United States)

    ... Safety Injury Rehabilitation Emotional Well-Being Mental Health Sex and Birth Control Sex and Sexuality Birth Control Family Health Infants and ... Kids and Teens Talking to Your Kids About Sex Talking to Your Kids About Sex Share Print ...

  15. Sex workers talk about sex work: six contradictory characteristics of legalised sex work in Melbourne, Australia.

    Science.gov (United States)

    Begum, Sufia; Hocking, Jane S; Groves, Jan; Fairley, Christopher K; Keogh, Louise A

    2013-01-01

    Despite research suggesting that legal sex work is safe and that emotional risks and social stigma are of greater concern than health risks, much research on sex work has focused on health risks. Given the legalisation of sex work in Victoria, Australia, it is timely to look beyond health. Three focus groups were conducted with a total of 14 female sex workers on their experience of legal sex work, both positive and negative, and the social acceptability of their profession. Thematic analysis was used to identify the key ways that sex workers described sex work. Women saw legal sex work as safer than illegal sex work, but still not socially acceptable. However, they also described six contradictory elements of sex work, which was seen as: financially rewarding and entrapping; empowering and demeaning; increasing some opportunities while reducing others; flexible and demanding; offering both intimacy and competition; and leading to a 'double life'. While legalisation has improved the safety of sex work, stigma and discrimination persist.

  16. Fungal Sex: The Mucoromycota.

    Science.gov (United States)

    Lee, Soo Chan; Idnurm, Alexander

    2017-03-01

    Although at the level of resolution of genes and molecules most information about mating in fungi is from a single lineage, the Dikarya, many fundamental discoveries about mating in fungi have been made in the earlier branches of the fungi. These are nonmonophyletic groups that were once classified into the chytrids and zygomycetes. Few species in these lineages offer the potential of genetic tractability, thereby hampering the ability to identify the genes that underlie those fundamental insights. Research performed during the past decade has now established the genes required for mating type determination and pheromone synthesis in some species in the phylum Mucoromycota, especially in the order Mucorales. These findings provide striking parallels with the evolution of mating systems in the Dikarya fungi. Other discoveries in the Mucorales provide the first examples of sex-cell type identity being driven directly by a gene that confers mating type, a trait considered more of relevance to animal sex determination but difficult to investigate in animals. Despite these discoveries, there remains much to be gleaned about mating systems from these fungi.

  17. Sex Ratio Elasticity Influences the Selection of Sex Ratio Strategy

    Science.gov (United States)

    Wang, Yaqiang; Wang, Ruiwu; Li, Yaotang; (Sam) Ma, Zhanshan

    2016-12-01

    There are three sex ratio strategies (SRS) in nature—male-biased sex ratio, female-biased sex ratio and, equal sex ratio. It was R. A. Fisher who first explained why most species in nature display a sex ratio of ½. Consequent SRS theories such as Hamilton’s local mate competition (LMC) and Clark’s local resource competition (LRC) separately explained the observed deviations from the seemingly universal 1:1 ratio. However, to the best of our knowledge, there is not yet a unified theory that accounts for the mechanisms of the three SRS. Here, we introduce the price elasticity theory in economics to define sex ratio elasticity (SRE), and present an analytical model that derives three SRSs based on the following assumption: simultaneously existing competitions for both resources A and resources B influence the level of SRE in both sexes differently. Consequently, it is the difference (between two sexes) in the level of their sex ratio elasticity that leads to three different SRS. Our analytical results demonstrate that the elasticity-based model not only reveals a highly plausible mechanism that explains the evolution of SRS in nature, but also offers a novel framework for unifying two major classical theories (i.e., LMC & LRC) in the field of SRS research.

  18. Stress and sex: does cortisol mediate sex change in fish?

    Science.gov (United States)

    Goikoetxea, Alexander; Todd, Erica V; Gemmell, Neil J

    2017-12-01

    Cortisol is the main glucocorticoid (GC) in fish and the hormone most directly associated with stress. Recent research suggests that this hormone may act as a key factor linking social environmental stimuli and the onset of sex change by initiating a shift in steroidogenesis from estrogens to androgens. For many teleost fish, sex change occurs as a usual part of the life cycle. Changing sex is known to enhance the lifetime reproductive success of these fish and the modifications involved (behavioral, gonadal and morphological) are well studied. However, the exact mechanism behind the transduction of the environmental signals into the molecular cascade that underlies this singular process remains largely unknown. We here synthesize current knowledge regarding the role of cortisol in teleost sex change with a focus on two well-described transformations: temperature-induced masculinization and socially regulated sex change. Three non-mutually exclusive pathways are considered when describing the potential role of cortisol in mediating teleost sex change: cross-talk between GC and androgen pathways, inhibition of aromatase expression and upregulation of amh (the gene encoding anti-Müllerian hormone). We anticipate that understanding the role of cortisol in the initial stages of sex change will further improve our understanding of sex determination and differentiation across vertebrates, and may lead to new tools to control fish sex ratios in aquaculture. © 2017 Society for Reproduction and Fertility.

  19. Sex differentials in mortality.

    Science.gov (United States)

    1970-06-01

    The questions leing considered are whether a higher female than male mortality rate exists in Ceylon, India, and Pakistan, and whether this sex differential can account for the observed high male sex ratios. There is a choice between explaining the recorded masculinity of the Indian population by assuming that the subordinate position of women caused their omission from the census or that it caused their unrecorded death in childhood. The 1951 census report of India states that there is a traditional fondness for male issues in most parts of the country and a corresponding dislike for female children. However, a life table for India applied to the 1951 census gave a higher average female age at death 34.7 years as opposed to 33.5 years for male. Other estimates for India and Pakistan for the period 1951-1961 give 37.8 years for life expectancy for males and 36.98 for females. In 1953 the female death rate in Ceylon was over 80% higher than that of the males in the most reproductive ages, 20-29. In 1963 the female excess mortality at the same ages was still 25%, and in the age group 30-34 almost a 1/3 higher. In India the female death rate at ages 15-44 was 38% higher than that of the males in the 1958-1959 survey and as much as 174% higher in the Khanna rural survey, 1956-1960. In Pakistan a Population growth Estimate experiment conducted during 1962-1965 on a national probability sample has shown that in the ages 15-44 the female death rate was 75% higher than that of the males. High maternal mortality was the major reason. In addition, female mortality among young children over age 1 year was 24% higher in 1965 and 1963. There was little difference between the rates of mortality of the 2 sexes at age 45 and above. Recent trends in Ceylon show considerable improvement in maternal mortality which has reduced by 22% the ratio of female to male mortality at age 15-44. Also the ratio at ages 1-9 fell by 8%. to .1 of a year for every calendar year to 1980.

  20. Sex differences in drug abuse.

    Science.gov (United States)

    Becker, Jill B; Hu, Ming

    2008-01-01

    Sex differences are present for all of the phases of drug abuse (initiation, escalation of use, addiction, and relapse following abstinence). While there are some differences among specific classes of abused drugs, the general pattern of sex differences is the same for all drugs of abuse. Females begin regularly self-administering licit and illicit drugs of abuse at lower doses than do males, use escalates more rapidly to addiction, and females are at greater risk for relapse following abstinence. In this review, sex differences in drug abuse are discussed for humans and in animal models. The possible neuroendocrine mechanisms mediating these sex differences are discussed.

  1. Sex Reversal in Amphibians.

    Science.gov (United States)

    Flament, Stéphane

    2016-01-01

    Amphibians have been widely used to study developmental biology due to the fact that embryo development takes place independently of the maternal organism and that observations and experimental approaches are easy. Some amphibians like Xenopus became model organisms in this field. In the first part of this article, the differentiation of the gonads in amphibians and the mechanisms governing this process are reviewed. In the second part, the state of the art about sex reversal, which can be induced by steroid hormones in general and by temperature in some species, is presented. Also information about pollutants found in the environment that could interfere with the development of the amphibian reproductive apparatus or with their reproductive physiology is given. Such compounds could play a part in the amphibian decline, since in the wild, many amphibians are endangered species. © 2016 S. Karger AG, Basel.

  2. Sex ratio variation and sex determination in Urtica dioica

    NARCIS (Netherlands)

    Glawe, Grit Anja

    2006-01-01

    This thesis will first document on variation in progeny sex ratios among individual female plants of Urtica dioica at our field site in Meijendel (Chapter 2). Next, we show that there is also considerable sex ratio variation among male and female flowering shoots in 26 natural populations studied

  3. Sense about Sex: Media, Sex Advice, Education and Learning

    Science.gov (United States)

    Attwood, Feona; Barker, Meg John; Boynton, Petra; Hancock, Justin

    2015-01-01

    The media are widely acknowledged as important in sex and relationship education, but they are usually associated with "bad" effects on young people in contrast to the "good" knowledge represented by more informational and educational formats. In this paper we look at sex advice giving in newspapers, magazines and television in…

  4. Sex differences in adolescent depression: do sex hormones determine vulnerability?

    NARCIS (Netherlands)

    Naninck, E.F.G.; Lucassen, P.J.; Bakker, J.

    2011-01-01

    Depression is one of the most common, costly and severe psychopathologies worldwide. Its incidence, however, differs significantly between the sexes, and depression rates in women are twice those of men. Interestingly, this sex difference emerges during adolescence. Although the adolescent period is

  5. Sex and Age Differences in Attitude toward the Opposite Sex.

    Science.gov (United States)

    Silver, Rawley

    1997-01-01

    Examines fantasies about the opposite sex expressed by 116 children, adolescents, and adults responding to the Drawing from Imagination task of the Silver Drawing Test of Cognition and Emotion. Results indicate that both males and females expressed more negative than positive feelings toward subjects of the opposite sex. Males were more negative.…

  6. Sex Education: Talking to Toddlers and Preschoolers about Sex

    Science.gov (United States)

    Healthy Lifestyle Sexual health Sex education often begins with a child's curiosity about his or her body. Here's how to set the stage for ... Original article: http://www.mayoclinic.org/healthy-lifestyle/sexual-health/in-depth/sex-education/art-20044104 . Mayo Clinic Footer Legal Conditions and ...

  7. The trouble with sex differences.

    Science.gov (United States)

    Eliot, Lise

    2011-12-22

    Sex differences in the brain are real and clinically important but often grossly distorted in popular discourse. Considering the public's deep fascination with sex difference research and its impact on issues from mental health to education and workplace equity, neuroscientists should pay greater heed to its misappropriation and to studying how gender enculturation shapes neural function. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Sex-work harm reduction.

    Science.gov (United States)

    Rekart, Michael L

    2005-12-17

    Sex work is an extremely dangerous profession. The use of harm-reduction principles can help to safeguard sex workers' lives in the same way that drug users have benefited from drug-use harm reduction. Sex workers are exposed to serious harms: drug use, disease, violence, discrimination, debt, criminalisation, and exploitation (child prostitution, trafficking for sex work, and exploitation of migrants). Successful and promising harm-reduction strategies are available: education, empowerment, prevention, care, occupational health and safety, decriminalisation of sex workers, and human-rights-based approaches. Successful interventions include peer education, training in condom-negotiating skills, safety tips for street-based sex workers, male and female condoms, the prevention-care synergy, occupational health and safety guidelines for brothels, self-help organisations, and community-based child protection networks. Straightforward and achievable steps are available to improve the day-to-day lives of sex workers while they continue to work. Conceptualising and debating sex-work harm reduction as a new paradigm can hasten this process.

  9. [Sex-linked juvenile retinoschisis].

    Science.gov (United States)

    François, P; Turut, P; Soltysik, C; Hache, J C

    1976-02-01

    About 13 observations of sexe linked juvenile retinoschisis, the authors describe the ophthalmoscopic, fluorographic and functional aspects of the disease whose caracteristics are:--its sexe linked recessive heredity; --its clinical characterestics associating: a microcystic macular degeneration, peripheral retinal lesions, vitreous body alterations, --an electroretinogram of the negative type.

  10. Sex Differences Reappraised: A Rebuttal

    Science.gov (United States)

    Tolor, Alexander; Brannigan, Gary G.

    1975-01-01

    This rebuttal of the criticisms made by Evans and Sperekas points to the fact that sex differences have been found by the authors on locus of control scales, that the purported sex-biased items in the Future Events Test are not necessarily outside the response repetoire of women, and the criticism of including female relevant items cannot be…

  11. Teaching Sex Education in Thailand

    Science.gov (United States)

    Kay, Noy S.; Jones, Megan R.; Jantaraweragul, Sudgasame

    2010-01-01

    The purposes of this study were to examine the current situation pertaining to the teaching of sex education and identify barriers to teaching sex education among Thai health education teachers. A survey questionnaire was administered to 193 health education teachers who participated in this study. The questionnaire was comprised of three parts:…

  12. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... arrow How should people deal with spasticity during sex? play_arrow What about positions and foreplay after a spinal cord injury? play_arrow What about orgasms and sensation during sex after a spinal cord injury? play_arrow What ...

  13. Moral Pluralism and Sex Education

    Science.gov (United States)

    Corngold, Josh

    2013-01-01

    How should common schools in a liberal pluralist society approach sex education in the face of deep disagreement about sexual morality? Should they eschew sex education altogether? Should they narrow its focus to facts about biology, reproduction, and disease prevention? Should they, in addition to providing a broad palette of information about…

  14. Sex in a test tube

    NARCIS (Netherlands)

    Pesce, Diego; Lehman, Niles; Visser, de Arjan

    2016-01-01

    The origin and evolution of sex, and the associated role of recombination, present a major problem in biology. Sex typically involves recombination of closely related DNA or RNA sequences,which is fundamentally a randomprocess that creates but also breaks up beneficial allele combinations.

  15. Sex reassignment surgery

    Directory of Open Access Journals (Sweden)

    Bižić Marta

    2015-01-01

    Full Text Available Transsexualism, or gender incongruence, presents a state in which a person's assigned sex at birth conflicts with their psychological gender. It is classified in International Classification of Diseases as F64. Treating these persons require multidisciplinary approach, including psychiatrist, endocrinologist, gynecologist, urologist, plastic and reconstructive surgeon. Genital reconstruction is the final step in transition, and can be performed when all other conditions required by World Professional Association for Transgender Health (WPATH are accomplished. Female to male sex reassignment surgery Several surgical procedures can be done in female to male transsexuals, including mastectomy, removal of female genitalia, metoidioplasty, scrotoplasty with implantation of testicular implants, as well as total phalloplasty. The current operative technique of metoidioplasty comprise the following steps: vaginal removal, the release of the ventral chordee and clitoral ligaments, straightening and lengthening of the clitoris, urethroplasty by combining buccal mucosa graft and genital flaps and scrotoplasty with insertion of testicle prostheses. The goal is to perform all these procedures in one stage, and that makes our team famous worldwide. Metoidioplasty results in excellent cosmetic outcome with completely preserved sensitivity and sexual arousal, enables voiding while standing, but without ability to penetrate due to small size of the neophallus. Considering these advantages, including low complication rate, patients often choose this option. For those who require bigger phallus which enables implantation of penile prosthesis, several surgical techniques have been reported using either available local vascularized tissue or microvascular tissue transfer. However, none of them satisfy all the goals of modern penile construction, i.e. reproducibility, tactile and erogenous sensation, a competent neourethra with a meatus at the top of the neophallus

  16. Constructions of Sex and Gender

    DEFF Research Database (Denmark)

    Schleicher, Marianne

    2011-01-01

    Responding to the ethical and performative call of Judith Butler not to propagate the sex- and gender-related violence of the imbedded discourse that we study, this article inquires into the discursive strategies of Jewish scripture by analysing how it orchestrates certain norms of sex and gender...... and make them serve the overall aim of securing cultural survival. Following this, it traces reflections on persons of ambiguous or indeterminate sex from rabbinic to modern Judaism so as to inquire into the rabbinic dependency on scripture when non-conforming individuals challenge its bipolar sex...... Jews and non-Jews are able to influence their own representations of sex and gender and thus liberate themselves from the normativity implied by scriptural discourse....

  17. Sex differences in primary hypertension

    Science.gov (United States)

    2012-01-01

    Men have higher blood pressure than women through much of life regardless of race and ethnicity. This is a robust and highly conserved sex difference that it is also observed across species including dogs, rats, mice and chickens and it is found in induced, genetic and transgenic animal models of hypertension. Not only do the differences between the ovarian and testicular hormonal milieu contribute to this sexual dimorphism in blood pressure, the sex chromosomes also play a role in and of themselves. This review primarily focuses on epidemiological studies of blood pressure in men and women and experimental models of hypertension in both sexes. Gaps in current knowledge regarding what underlie male-female differences in blood pressure control are discussed. Elucidating the mechanisms underlying sex differences in hypertension may lead to the development of anti-hypertensives tailored to one's sex and ultimately to improved therapeutic strategies for treating this disease and preventing its devastating consequences. PMID:22417477

  18. [Sex role and sports].

    Science.gov (United States)

    Darlison, E

    2000-11-01

    Gender inequality in all areas of life remains a global problem despite efforts over the past twenty years in particular to address the situation. In physical activity and sport the inequality between women and men is particularly pronounced in almost all countries, although it differs in degree. Two of the main reasons why inequality between women and men physical activity and sport is more extreme than in many other areas of social life are the result of the close association between the attributes required for sport and those associated with traditional concepts of stereotypical, hegemonic masculinity, and a lack of understanding of the difference between sex and gender. In sport and physical activity physical differences between men and women have been confused with socially constructed differences i.e. physical differences have been confused with gender differences, and this confusion has been used to justify women's lesser and limited participation at all levels. To achieve equality between women and men in physical activity and sport it will be essential that gender is identified and understood as a socially constructed and fluid concept which is a product of the relations between women and men. The fact that women bear children or are generally less physically powerful than men is not sufficient to justify why it is not considered appropriate for women to participate in certain forms of physical activity or why their participation is less valued than the participation of men. An understanding of gender and of the construction of gender relations is an important pre-requisite to addressing the inequality between women and men in physical activity and sport and in developing policies and programs which include, and are of equal benefit to both sexes. While more research on the benefits of participation in physical activity is needed, there is currently sufficient information available to identify the health related and social value of participation to both

  19. Same sex families and children

    Directory of Open Access Journals (Sweden)

    Mršević Zorica

    2009-01-01

    Full Text Available Introduction comprises the information on two main forms of same sex families, civic partnership (same sex partnership and same sex marriage. Countries and various status modalities of legal regulations are mentioned. The main part of the text is dedicated to presentation of the findings of the most recent research on various aspects regarding children of same sex partnerships. It comprises presentations grouped in four main chapters: acceptance of same sex partnerships, acceptance of legal recognition of the same sex partnerships, family plans of homosexual teenagers, and raising children within and by the same sex partners. Also the real life cases mirroring legal changes through their life destinies are presented, such is e.g. the Irish way to legalization of the same sex partnerships. In addition, a love story of two women crowned by giving birth of their four children is mentioned. Reasons against and negative reactions the author puts under the title Homophobia. In the Concluding remarks, the author presents the most recent examples of legal changes happened in Norway, Ecuador, and in the American states of California and Connecticut. It was also stated that in European countries of low birth rate, the same sex families are inevitably identified as one of demographically valuable source of creating and raising children, which is worthy to be supported, rather than being hindered without reason and discriminated. Although different than a model of heterosexual family, same sex partnerships neither are harrowing to traditional family values, nor reflex of any kind of promiscuous, antisocial behavior, avoidance of parenthood, and negation of family. Quite opposite, these families are an outcome of endeavors of homosexuals not to be deprived of family, parenthood and all of other values of stabile, monogamous, emotional/sexual socially accepted and legally recognized and regulated conventional family. .

  20. The sex and sex determination in Pyropia haitanensis (Bangiales, Rhodophyta).

    Science.gov (United States)

    Zhang, Yuan; Yan, Xing-hong; Aruga, Yusho

    2013-01-01

    Pyropia haitanensis has a biphasic life cycle with macroscopic gametophytic blade (n) and microscopic filamentous conchocelis (2n) phase. Its gametophytic blades have long been believed to be mainly dioecious. However, when crossing the red mutant (R, ♀) with the wild type (W, ♂), the parental colors were segregated in F1 blades, of which 96.1% were linearly sectored with 2-4 color sectors. When color sectors were excised from the color-sectored blades and cultured singly, 99.7% of the color sectors appeared to be unisexual with an equal sex ratio. Although the sex of color sector did not genetically link with its color, the boundaries of both sex and color sectors coincided precisely. About 87.9% of the examined color-sectored blades were monoecious and the percentage increased with the number of color sectors of a blade. The gametophytic blades from each conchocelis strain produced by parthenogenesis of the excised color sectors were unisexual and unicolor, showing the same sex and color as their original sectors. These results indicate that most of the sexually reproduced Py. haitanensis blades are monoecious, and their sex is controlled by segregation of a pair of alleles during meiosis of conchospore, forming a sex-sectored tetrad. During the subsequent development of blades, one or two lower cell(s) of the tetrad contribute mainly to rhizoid formation, and rarely show their sexual phenotype, leading to reduced frequency of full sex phenotype of the meiotic blades. Moreover, the aberrant segregations of sex genes or color genes in a few of F1 blades were probably due to gene conversions, but there was no sex transfer in Py. haitanensis.

  1. Effect of age and sex on fiber and follicle characteristics of an Iranian ...

    African Journals Online (AJOL)

    All the hair follicles were surrounded by associated structures such as the sweat and sebaceous glands and arrector pili muscles and located only in papillary layer of the dermis. The most common number of the secondary hair follicles in compound hair follicles was 4. The histology of all fibers and follicles in various skin ...

  2. Talk to Your Kids about Sex

    Science.gov (United States)

    ... Topic En español Talk to Your Kids about Sex Browse Sections The Basics Overview Bodies and Puberty ... healthy expectations for their relationships. Talk about opposite-sex and same-sex relationships. When you talk about ...

  3. Fungal Sex: The Basidiomycota.

    Science.gov (United States)

    Coelho, Marco A; Bakkeren, Guus; Sun, Sheng; Hood, Michael E; Giraud, Tatiana

    2017-06-01

    Fungi of the Basidiomycota, representing major pathogen lineages and mushroom-forming species, exhibit diverse means to achieve sexual reproduction, with particularly varied mechanisms to determine compatibilities of haploid mating partners. For species that require mating between distinct genotypes, discrimination is usually based on both the reciprocal exchange of diffusible mating pheromones, rather than sexes, and the interactions of homeodomain protein signals after cell fusion. Both compatibility factors must be heterozygous in the product of mating, and genetic linkage relationships of the mating pheromone/receptor and homeodomain genes largely determine the complex patterns of mating-type variation. Independent segregation of the two compatibility factors can create four haploid mating genotypes from meiosis, referred to as tetrapolarity. This condition is thought to be ancestral to the basidiomycetes. Alternatively, cosegregation by linkage of the two mating factors, or in some cases the absence of the pheromone-based discrimination, yields only two mating types from meiosis, referred to as bipolarity. Several species are now known to have large and highly rearranged chromosomal regions linked to mating-type genes. At the population level, polymorphism of the mating-type genes is an exceptional aspect of some basidiomycete fungi, where selection under outcrossing for rare, intercompatible allelic variants is thought to be responsible for numbers of mating types that may reach several thousand. Advances in genome sequencing and assembly are yielding new insights by comparative approaches among and within basidiomycete species, with the promise to resolve the evolutionary origins and dynamics of mating compatibility genetics in this major eukaryotic lineage.

  4. Sex Hormones and Ischemic Stroke

    DEFF Research Database (Denmark)

    Holmegard, Haya N; Nordestgaard, Børge G; Jensen, Gorm B

    2016-01-01

    CONTEXT AND OBJECTIVE: Whether endogenous sex hormones are associated with ischemic stroke (IS) is unclear. We tested the hypothesis that extreme concentrations of endogenous sex hormones are associated with risk of IS in the general population. DESIGN, SETTING, AND PARTICIPANTS: Adult men (n...... = 4615) and women (n = 4724) with measurements of endogenous sex hormones during the 1981-1983 examination of the Copenhagen City Heart Study, Denmark, were followed for up to 29 years for incident IS, with no loss to follow-up. Mediation analyses assessed whether risk of IS was mediated through...

  5. Adolescents, sex, and the media.

    Science.gov (United States)

    Strasburger, Victor C

    2012-04-01

    In the absence of effective sex education in the United States, the media have arguably become the leading sex educator for children and teenagers. Considerable research now exists that attests to the ability of the media to influence adolescents' attitudes and beliefs about sex and sexuality. In addition, new research has found a significant link between exposure to sexual content in the media and earlier onset of sexual intercourse. Although there is little research on the behavioral effects of "new" media, they are discussed as well. Suggestions for clinicians, parents, the federal government, and the entertainment industry are provided.

  6. Whose crazy investment in sex?

    Science.gov (United States)

    Mandlis, Lane R

    2011-01-01

    By probing the processes of exclusion of transsexuals from the political sphere, this article offers contributions to social and political theory through an examination of the processes of exclusion from the category "human." This article considers how the erasure of investment in their own embodied sex constructs a platform from which to blame others for sex/gender variance, as well as to justify that blaming. Bringing together Giorgio Agamben, Georges Bataille, Judith Butler, and Nikolas Rose with transphobia, medicalization in psychiatry, law, and ethopolitics, this article questions whose investment in sexed embodiment counts and why that investment might be seen as "crazy."

  7. Disentangling the benefits of sex.

    Science.gov (United States)

    Roze, Denis

    2012-01-01

    Understanding the evolutionary advantage of sexual reproduction remains one of the most fundamental questions in evolutionary biology. Most of the current hypotheses rely on the fact that sex increases genetic variation, thereby enhancing the efficiency of natural selection; an important body of theoretical work has defined the conditions under which sex can be favoured through this effect. Over the last decade, experimental evolution in model organisms has provided evidence that sex indeed allows faster rates of adaptation. A new study on facultatively sexual rotifers shows that increased rates of sex can be favoured during adaptation to new environmental conditions and explores the cause of this effect. The results provide support for the idea that the benefits of increasing genetic variation may compensate for the short-term costs of sexual reproduction.

  8. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... a spinal cord injury? play_arrow What about oral sex after a spinal cord injury? ... injuries. The website does not provide medical advice, recommend or endorse health care products or services, or control the information ...

  9. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Spinal Cord Injury Guy W. Fried, MD Substance Abuse and Spinal Cord Injury Allen Heinemann, PhD How ... spinal cord injury? play_arrow Can men and women still have sex after a spinal cord injury? ...

  10. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility ... injury? What is a Spinal Cord Injury? SCI Medical Experts People Living With SCI Personal Experiences By ...

  11. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... spinal cord injury? play_arrow Can men and women still have sex after a spinal cord injury? play_arrow How is sexual function in women affected by a spinal cord injury? play_arrow ...

  12. Sex differences, gender and addiction.

    Science.gov (United States)

    Becker, Jill B; McClellan, Michele L; Reed, Beth Glover

    2017-01-02

    This review discusses alcohol and other forms of drug addiction as both a sociocultural and biological phenomenon. Sex differences and gender are not solely determined by biology, nor are they entirely sociocultural. The interactions among biological, environmental, sociocultural, and developmental influences result in phenotypes that may be more masculine or more feminine. These gender-related sex differences in the brain can influence the responses to drugs of abuse, progressive changes in the brain after exposure to drugs of abuse and whether addiction results from drug-taking experiences. In addition, the basic laboratory evidence for sex differences is discussed within the context of four types of sex/gender differences. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  13. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Resources Peer Counseling Blog About Media Donate close search Understanding Spinal Cord Injury What is a Spinal ... male fertility? play_arrow Where can people get information on sex and fertility after a spinal cord ...

  14. Sex differences in cardiovascular function

    Czech Academy of Sciences Publication Activity Database

    Kolář, František; Ošťádal, Bohuslav

    2013-01-01

    Roč. 207, č. 4 (2013), s. 584-587 ISSN 1748-1708 Institutional support: RVO:67985823 Keywords : heart * vascular * risk factors * sex Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 4.251, year: 2013

  15. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Topic Resources Peer Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord Injury 101 David Chen, ...

  16. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord Injury ... 2525 info@facingdisability.com SIGN UP FOR OUR NEWSLETTER Your email address * This iframe contains the logic ...

  17. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... male fertility? play_arrow Where can people get information on sex and fertility after a spinal cord ... health care products or services, or control the information found on external websites. The Hill Foundation is ...

  18. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Topic Resources Peer Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord Injury 101 David ...

  19. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... after a spinal cord injury? play_arrow Can men and women still have sex after a spinal ... injury? play_arrow How is sexual function in men affected by a spinal cord injury ? play_arrow ...

  20. Gender socialization and sex affilation

    Directory of Open Access Journals (Sweden)

    Redžić Saduša F.

    2014-01-01

    Full Text Available The author's depth interviews with students of the University of Nis checked for the possibility of receptivity to sexual stereotypes and conditioning of sexual/gender socialization by sexual group affiliation. Examined the experiences and attitudes of students of both sexes regarding early gender socialization and it's characteristically stereotypes, stereotypes about dressing, instrumentalization of sexuality, the influence of parents/environment on the formation of sexual morality, own the gender socialization in the family, twin rules for the socialization of children of different gender and sex/gender roles in marriage. Belonging to the sex group has no effect on susceptibility to sexual stereotypes regarding early gender socialization and dressing. Difference may be seen in the effort to comment on and evaluate the wear behavior of girls more than a young man dressing, which may be an indicator for further research had sexual dimorphism in terms of dressing and nudity. It seems that the experience of respondents of both sexes are dependent primarily from the general family atmosphere (closeness, openness to communicate with each other, the absence of the traditional gender division of roles in the family/emotional distance from the parent of the opposite sex or of both parents, the rigidity, the strict division of gender roles in the family. In the first case, where both parents are involved in the upbringing of the child, relationships are intimate with both, and vice versa. Therefore, we can conclude about the lack of connection between the sex of the child and separated upbringing (traditional: the mother confides sexual education of women, a father of male child in the first case, and a link to another should only check to prove it. Sex does not condition susceptibility to stereotypes about education and gender roles. Traditionally, transitional and modern attitudes are equally represented in subjects of both sexes.

  1. Sex Differences in Drug Abuse

    OpenAIRE

    Becker, Jill B.; Hu, Ming

    2007-01-01

    Sex differences are present for all of the phases of drug abuse (initiation, escalation of use, addiction, and relapse following abstinence). While there are some differences among specific classes of abused drugs, the general pattern of sex differences is the same for all drugs of abuse. Females begin regularly self-administering licit and illicit drugs of abuse at lower doses than do males, use escalates more rapidly to addiction, and females are at greater risk for relapse following abstin...

  2. SEX DIFFERENCES, GENDER AND ADDICTION

    OpenAIRE

    Becker, Jill B.; McClellan, Michele L.; Reed, Beth Glover

    2017-01-01

    This review discusses alcohol/other drug addiction as both a sociocultural and biological phenomenon. Sex differences and gender are not solely determined by biology, nor are they entirely sociocultural. The interactions among biological, environmental, sociocultural and developmental influences result in phenotypes that may be more masculine or more feminine. These gender-related sex differences in the brain can influence the responses to drugs of abuse, progressive changes in the brain afte...

  3. Adaptive value of sex in microbial pathogens.

    Science.gov (United States)

    Michod, Richard E; Bernstein, Harris; Nedelcu, Aurora M

    2008-05-01

    Explaining the adaptive value of sex is one of the great outstanding problems in biology. The challenge comes from the difficulty in identifying the benefits provided by sex, which must outweigh the substantial costs of sex. Here, we consider the adaptive value of sex in viruses, bacteria and fungi, and particularly the information available on the adaptive role of sex in pathogenic microorganisms. Our general theme is that the varied aspects of sex in pathogens illustrate the varied issues surrounding the evolution of sex generally. These include, the benefits of sex (in the short- and long-term), as well as the costs of sex (both to the host and to the pathogen). For the benefits of sex (that is, its adaptive value), we consider three hypotheses: (i) sex provides for effective and efficient recombinational repair of DNA damages, (ii) sex provides DNA for food, and (iii) sex produces variation and reduces genetic associations among alleles under selection. Although the evolution of sex in microbial pathogens illustrates these general issues, our paper is not a general review of theories for the evolution of sex in all organisms. Rather, we focus on the adaptive value of sex in microbial pathogens and conclude that in terms of short-term benefits, the DNA repair hypothesis has the most support and is the most generally applicable hypothesis in this group. In particular, recombinational repair of DNA damages may substantially benefit pathogens when challenged by the oxidative defenses of the host. However, in the long-term, sex may help get rid of mutations, increase the rate of adaptation of the population, and, in pathogens, may infrequently create new infective strains. An additional general issue about sex illustrated by pathogens is that some of the most interesting consequences of sex are not necessarily the reasons for which sex evolved. For example, antibiotic resistance may be transferred by bacterial sex, but this transfer is probably not the reason sex

  4. Sex reassignment surgery in Thailand.

    Science.gov (United States)

    Chokrungvaranont, Prayuth; Tiewtranon, Preecha

    2004-11-01

    Many years ago Thai society considered transsexualism (Gender identity disorder or Gender dysphoria) which is commonly known as Kathoey (a word originally used to denote hermaphrodites), Sao Prapet Song or Tut (as in 'Tootsie') were low class citizens, dirty dressing and had to hide in a dark corner selling their services as prostitutes. This made us unwilling to do sex reassignment surgery for this group of people because the idea of eradicating normal sexual organs for the purpose that was not accepted by the society. Consequently the authors have experience in cases where these people wandered seeking doctors who had no competency nor enough experience to do the surgery. The authors could not inhibit the desire of these people who usually suffer from gender identity disorder from strongly wishing to change their genital sex to the sex they want. The outcome of the surgery was not satisfactory for the patients. There were complications and sequelae which caused the authors to correct them later which might be more difficult than doing the original surgery. In addition there were more studies about the etiology and affect of the disorder on these people that changed the social point of view. The women who wanted to be a him and men who would like to be a her should be considered as patients who need to be cured to set the harmony about their genetic sex and the desire to be the opposite sex and also to be regarded by others as a member of that other sex. The treatments of transsexualism usually begin with conventional psychiatric and endocrinological treatment to adjust the mind to the body. For those who failed conservative treatment in adjusting the mind to the body then sex reassignment surgery will be the only way to transform their body to their mind and give the best result in properly selected patients. Preecha Tiewtranon, the pioneer in sex reassignment surgery in Thailand, did his transsexualism case in 1975 together with Dr. Prakob Thongpeaw. Sex

  5. Sex differences in the brain-an interplay of sex steroid hormones and sex chromosomes.

    Science.gov (United States)

    Grgurevic, Neza; Majdic, Gregor

    2016-09-01

    Although considerable progress has been made in our understanding of brain function, many questions remain unanswered. The ultimate goal of studying the brain is to understand the connection between brain structure and function and behavioural outcomes. Since sex differences in brain morphology were first observed, subsequent studies suggest different functional organization of the male and female brains in humans. Sex and gender have been identified as being a significant factor in understanding human physiology, health and disease, and the biological differences between the sexes is not limited to the gonads and secondary sexual characteristics, but also affects the structure and, more crucially, the function of the brain and other organs. Significant variability in brain structures between individuals, in addition to between the sexes, is factor that complicates the study of sex differences in the brain. In this review, we explore the current understanding of sex differences in the brain, mostly focusing on preclinical animal studies. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

  6. A Review of The Sex EDcyclopedia

    Science.gov (United States)

    Herman, Jeff; Andelloux, Megan

    2012-01-01

    While virtually all sex education books for teenagers focus on sexual health, Jo Langford's "The Sex EDcyclopedia" offers comprehensive and empowering information specifically for teen males about their sexuality and how it may be positively experienced. This review examines the strengths of "The Sex EDcyclopedia" as a sex education resource and…

  7. Sex work: a comparative study.

    Science.gov (United States)

    McCarthy, Bill; Benoit, Cecilia; Jansson, Mikael

    2014-10-01

    Explanations of adult involvement in sex work typically adopt one of two approaches. One perspective highlights a variety of negative experiences in childhood and adolescence, including physical and sexual abuse, family instability, poverty, associations with "pimps" and other exploiters, homelessness, and drug use. An alternative account recognizes that some of these factors may be involved, but underscores the contribution of more immediate circumstances, such as current economic needs, human capital, and employment opportunities. Prior research offers a limited assessment of these contrasting claims: most studies have focused exclusively on people working in the sex industry and they have not assessed the independent effects of life course variables central to these two perspectives. We add to this literature with an analysis that drew on insights from life course and life-span development theories and considered the contributions of factors from childhood, adolescence, and adulthood. Our comparative approach examined predictors of employment in sex work relative to two other low-income service or care work occupations: food and beverage serving and barbering and hairstyling. Using data from a study of almost 600 workers from two cities, one in Canada and the other in the United States, we found that both immediate circumstances and negative experiences from early life are related to current sex work involvement: childhood poverty, abuse, and family instability were independently associated with adult sex work, as were limited education and employment experience, adult drug use, and marital status.

  8. Sex selection: treating different cases differently.

    Science.gov (United States)

    Dickens, B M; Serour, G I; Cook, R J; Qiu, R-Z

    2005-08-01

    This paper contrasts ethical approaches to sex selection in countries where discrimination against women is pervasive, resulting in selection against girl children, and in countries where there is less general discrimination and couples do not prefer children of either sex. National sex ratio imbalances where discrimination against women is common have resulted in laws and policies, such as in India and China, to deter and prevent sex selection. Birth ratios of children can be affected by techniques of prenatal sex determination and abortion, preconception sex selection and discarding disfavored embryos, and prefertilization sperm sorting, when disfavored sperm remain unused. Incentives for son preference are reviewed, and laws and policies to prevent sex selection are explained. The elimination of social, economic and other discrimination against women is urged to redress sex selection against girl children. Where there is no general selection against girl children, sex selection can be allowed to assist families that want children of both sexes.

  9. Sex hormone binding globulin phenotypes

    DEFF Research Database (Denmark)

    Cornelisse, M M; Bennett, Patrick; Christiansen, M

    1994-01-01

    Human sex hormone binding globulin (SHBG) is encoded by a normal and a variant allele. The resulting SHBG phenotypes (the homozygous normal SHBG, the heterozygous SHBG and the homozygous variant SHBG phenotype) can be distinguished by their electrophoretic patterns. We developed a novel detection....... This method of detection was used to determine the distribution of SHBG phenotypes in healthy controls of both sexes and in five different pathological conditions characterized by changes in the SHBG level or endocrine disturbances (malignant and benign ovarian neoplasms, hirsutism, liver cirrhosis...... on the experimental values. Differences in SHBG phenotypes do not appear to have any clinical significance and no sex difference was found in the SHBG phenotype distribution....

  10. Sex differences in cough reflex.

    Science.gov (United States)

    Plevkova, J; Buday, T; Kavalcikova-Bogdanova, N; Ioan, I; Demoulin-Alexikova, S

    2017-11-01

    Majority of patients visiting cough clinics are postmenopausal women, who are affected by intractable cough for years. Why the cough reflex becomes exaggerated in women is not known. Basic research excludes females from the studies contributing to the sex bias which may be responsible for lack of understanding of "hypersensitive" cough in women. Biological and behavioural differences between women and men are the factors affecting cough physiology. Gender also shapes the patterns of behaviour and determines the character of environmental exposures which differs between sexes. The article offers an insight into the physiology of the cough, differences in the maturation of it and biological, social and behavioural factors contributing to the sex differences in cough. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Incarcerated Dutch Juvenile Sex Offenders Compared with Non-Sex Offenders

    Science.gov (United States)

    van Wijk, Anton Ph.; Vreugdenhil, Coby; van Horn, Joan; Vermeiren, Robert; Doreleijers, Theo A. H.

    2007-01-01

    There is some debate about whether or not sex offenders are similar to non-sex offenders with regard to family background (parental characteristics), personality, and psychopathology. The central aim of this study focused on the comparison of juvenile sex offenders and non-sex offenders. The sample consisted of incarcerated juvenile male sex (n =…

  12. The Stability of Same-Sex Cohabitation, Different-Sex Cohabitation, and Marriage

    Science.gov (United States)

    Lau, Charles Q.

    2012-01-01

    This study contributes to the emerging demographic literature on same-sex couples by comparing the level and correlates of union stability among 4 types of couples: (a) male same-sex cohabitation, (b) female same-sex cohabitation, (c) different-sex cohabitation, and (d) different-sex marriage. The author analyzed data from 2 British birth cohort…

  13. Learning about Sex: Resource Guide for Sex Educators. Revised Edition

    Science.gov (United States)

    Huberman, Barbara

    2011-01-01

    Whether you are someone new to the field of sex education, trying to start a library or resource center on adolescent sexual health, or an old pro, this guide should give you a basic orientation to what's available to support your work. These resources are important to advancing positive attitudes toward adolescent sexual health and the author…

  14. Sex Education: Talking to Your Teen about Sex

    Science.gov (United States)

    ... might miss the best opportunities. Instead, think of sex education as an ongoing conversation. Here are some ideas to help you get started — and keep the discussion going. Seize the moment. When a TV program or music video raises issues about responsible sexual behavior, use it ...

  15. Sex differences and sex similarities in disgust sensitivity

    NARCIS (Netherlands)

    Tybur, J.M.; Bryan, A.D.; Lieberman, D.L.; Caldwell Hooper, A.E.; Merriman, L.A.

    2011-01-01

    Across two studies, we test for sex differences in the factor structure, factor loadings, concurrent validity, and means of the Three Domain Disgust Scale. In Study 1, we find that the Three Domain Disgust Scale has indistinguishable factor structure and factor loadings for men and women. In Study

  16. Elusive Sex Acts: Pleasure and Politics in Norwegian Sex Education

    Science.gov (United States)

    Svendsen, Stine H. Bang

    2012-01-01

    While there is little political opposition towards sex education as such in Norway, recent attempts at reforming the subject reveal underlying heteronormative presumptions that seem resistant to reform. While a focus on homosexuality is included in the national curriculum at all levels of compulsory education, the sexual practices involved in…

  17. Destabilising Sex work and Intimacy?

    DEFF Research Database (Denmark)

    Spanger, Marlene

    politikfelt prostitution. Undersøgelsen trækker på poststrukturalistisk feministisk teori og er baseret på interviews med kvindelige thailandske migranter, der sælger sex, og socialarbejdere samt deltagende observationer og diverse dokumenter. Afhandlingen falder i to dele. Den første del er rammen for de...... fire artikler, som består af en introduktion, en teoretisk ramme, metodeovervejelser og konklusion samt et overordnet forskningsspørgsmål: Hvordan destabiliserer og reproducerer kvindelige thailandske migranter, der sælger sex i Danmark, det danske prostitutionspolitikfelts kategorier ’sexarbejde’ og...

  18. AIDS prevention in the sex industry.

    Science.gov (United States)

    Morgan-thomas, R; Overs, C

    1992-01-01

    Most sex work research examines the impact of HIV on prostitutes and on society and involves testing prostitutes for HIV antibodies, but it does not examine the role of others in the sex industry. Sex industry workers include female prostitutes, transvestites, transsexuals, and male prostitutes, bar and brothel owners, taxi drivers, sex workers' partners, and sex business managers. Since sex workers provide sexual services to clients, they are in a perfect position to teach them about sexual health. Society must recognize that we cannot wish the sex industry away and that we need an effective health promotion strategy now. Some successful relevant AIDS education campaigns provide us some guidelines on how to develop campaigns. Any campaign targeting the sex industry should also target the public. Sex workers should participate in developing health messages and educational activities. They should also participate in the project. Any campaign must deal with major obstacles to safer sexual practices of which sex workers are aware and be consulted. Common obstacles are client demand for unprotected sex and irregular and inadequate supply of inexpensive condoms. A health promotion strategy cannot be effective, however, if sex workers do not have access to social support and health care services. Health promotion workers should also encourage local authorities to end discrimination of sex workers so they can freely obtain needed services. In some countries, sex workers operate fantasy workshops providing peers with ideas to sell sex services which reduce the risk of HIV transmission. Other campaigns distribute safer sex messages on small cards, cigarette lighters, key rings, condom packages, and T shirts. Training of sex workers other than prostitutes to reinforce safer sex messages to clients is also effective, e.g., taxi drivers can say they will take a client to a woman who uses condoms rather than to a clean girl. Street theater and puppets have also successfully

  19. [Sex differences and anesthesiology: preface and comments].

    Science.gov (United States)

    Nishno, Takashi

    2009-01-01

    In this special issue, the topic of sex difference in the field of anesthesiology is featured. Eight subtopics are discussed including 1) sex differences in cardiovascular medicine, 2) perioperative cardiovascular management, 3) sex differences in the respiratory functions of the upper airway, 4) sex differences in the anesthetic management, 5) sex differences in pain, 6) sex differences in laboratory medicine, 7) sex differences in pharmacokinetics of anesthetics, and 8) postoperative nausea and vomiting. Although recent clinical and experimental studies have shown the existence of sex and/or gender differences in many fields of medicine, our knowledge of sex differences in anesthesiology is apparently insufficient. I believe that anesthesiologists should pay more attention to this topic to improve our daily practice of anesthesia.

  20. Sex, Lies and Video Games

    Science.gov (United States)

    Kearney, Paul; Pivec, Maja

    2007-01-01

    Sex and violence in video games is a social issue that confronts us all, especially as many commercial games are now being introduced for game-based learning in schools, and as such this paper polls teenage players about the rules their parents and teachers may or may not have, and surveys the gaming community, ie, game developers to parents, to…

  1. Will sex selection reduce fertility?

    Science.gov (United States)

    Leung, S F

    1994-01-01

    Population control is one of the primary policies applied against poverty in many low income countries. The widespread prevalence of son preference in some countries such as China and India, however, works against any reduction of fertility. This is so because parents often continue to have children until they obtain the number of sons which they desire. The bias against girls has also led to higher abortion and mortality rates of female children. It is frequently argued that if sex selection methods are made available to parents so that they can control the gender of their children, population growth would be lowered and women's welfare improved. The author investigates both theoretically and numerically the impact of sex selection on fertility. A static quantity-quality model of fertility is used to compare fertility choices when parents cannot choose the gender of children versus a situation in which parents can choose gender. Empirical data are drawn from the 1976 Malaysian Family Life Survey. Analysis found that whether sex selection reduces fertility depends upon the second and third derivatives of the utility function and the child expenditure function. A numerical dynamic analysis is also presented. The simulation shows, using empirical dynamic models of fertility and the Monte Carlo integration technique, that sex selection on the firstborn child among the Chinese in Malaysia could reduce fertility by about 3%.

  2. Studying Sex Prejudice in Children.

    Science.gov (United States)

    Olsen, Nancy J.; Willemsen, Eleanor W.

    1978-01-01

    Explores a methodology for studying sex prejudice in children. First-, third-, and fifth-grade students were asked to rate the performance of an eight-year-old child identified as a girl for half of the subjects and as a boy for the remaining half. (BD)

  3. A Talk on Sex Discrimination.

    Science.gov (United States)

    Evers, Irving C.

    The topic of this speech covers the 1972 amendments to Title VII of the Civil Rights Act of 1964 and the subsequent court cases dealing with sex discrimination. The cases discussed cover maternity leaves for tenured as well as untenured teachers and other public employees. The issues basic to these cases involve mandatory maternity leaves at…

  4. Sex, spite, and selfish genes

    Indian Academy of Sciences (India)

    Nature's oracle: the life and work of W. D. Hamilton. Ullica Segerstrale .... Stemming partly from his study of sex ratios, Hamilton later began moving on to .... any scientific biography, has to strike a balance between sci- ence and the personal ...

  5. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... oral medications for erectile dysfunction? play_arrow What do people do with a catheter during sex? play_arrow How ... after a spinal cord injury? play_arrow How do women deal with menstruation after a spinal cord ...

  6. Sex and the Imperfect Fungi.

    Science.gov (United States)

    Dyer, Paul S; Kück, Ulrich

    2017-06-01

    Approximately 20% of species in the fungal kingdom are only known to reproduce by asexual means despite the many supposed advantages of sexual reproduction. However, in recent years, sexual cycles have been induced in a series of emblematic "asexual" species. We describe how these discoveries were made, building on observations of evidence for sexual potential or "cryptic sexuality" from population genetic analyses; the presence, distribution, and functionality of mating-type genes; genome analyses revealing the presence of genes linked to sexuality; the functionality of sex-related genes; and formation of sex-related developmental structures. We then describe specific studies that led to the discovery of mating and sex in certain Candida , Aspergillus , Penicillium , and Trichoderma species and discuss the implications of sex including the beneficial exploitation of the sexual cycle. We next consider whether there might be any truly asexual fungal species. We suggest that, although rare, imperfect fungi may genuinely be present in nature and that certain human activities, combined with the genetic flexibility that is a hallmark of the fungal kingdom, might favor the evolution of asexuality under certain conditions. Finally, we argue that fungal species should not be thought of as simply asexual or sexual, but rather as being composed of isolates on a continuum of sexual fertility.

  7. Creativity and Psychopathology: Sex Matters

    Science.gov (United States)

    Martín-Brufau, Ramón; Corbalán, Javier

    2016-01-01

    The association between creativity and psychopathology has, for decades, been a focus of heated debate fuelled by contradictory findings. Nevertheless, the findings suggest complex associations between creativity and psychopathology. Other studies have investigated the association between creativity and sex, with inconsistent results. The aim of…

  8. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... arrow How does caregiving for your partner often affect romantic relationships? play_arrow What are the common treatments for ... play_arrow How does a spinal cord injury affect male fertility? play_arrow Where can people get information on sex and ... Contact Us Terms of Use Site Map ...

  9. Great tit hatchling sex ratios

    NARCIS (Netherlands)

    Lessells, C.M.; Mateman, A.C.; Visser, J.

    1996-01-01

    The sex of Great Tit Parus major nestlings was determined using PCR RAPDs. Because this technique requires minute amounts of DNA, chicks could be sampled soon (0-2d) after hatching, before any nestling mortality occurred. The proportion of males among 752 chicks hatching in 102 broods (98.9% of

  10. Sex chromosomes in Ephestia kuehniella

    Czech Academy of Sciences Publication Activity Database

    Marec, František; Sahara, K.; Traut, W.

    2001-01-01

    Roč. 44, č. 1 (2001), s. 131 ISSN 0003-3995. [European Cytogenetics Conference /3./. 07.07.2001-10.07.2001, Paris] Institutional research plan: CEZ:AV0Z5007907 Keywords : Telomere * sex chromosomes * chromosome fragments Subject RIV: EB - Genetics ; Molecular Biology

  11. Sex Discrimination in Employment Practices.

    Science.gov (United States)

    California Univ., Los Angeles. Univ. Extension.

    The conference on sex discrimination in employment practices was held at the University of California at Los Angeles in cooperation with the Women's Bureau of the Department of Labor. Speeches included: (1) "New Legislation--New Action" by Rosalind K. Loring and William Foster, (2) "Compliance Policies and Procedures for Business and Industry" by…

  12. Sex determination in the Hymenoptera

    NARCIS (Netherlands)

    Heimpel, George E.; de Boer, Jetske G.

    2008-01-01

    The dominant and ancestral mode of sex determination in the Hymenoptera is arrhenotokous parthenogenesis, in which diploid females develop from fertilized eggs and haploid males develop from unfertilized eggs. We discuss recent progress in the understanding of the genetic and cytoplasmic mechanisms

  13. The prostitutions: power and sex

    Directory of Open Access Journals (Sweden)

    Adele Nunziante Cesaro

    2013-06-01

    Full Text Available The contemporary scenario features many and unusual versions of the sexual mercenary exchange, articulating new dynamics of desire. Prostitution remains a “question” which interrogates the gender and the difference between the sexes. According to a Freudian perspective, the authors present some reflection on the forms of sexuality today.

  14. Usage of the Terms Prostitution, Sex Work, Transactional Sex, and Survival Sex: Their Utility in HIV Prevention Research.

    Science.gov (United States)

    McMillan, Karen; Worth, Heather; Rawstorne, Patrick

    2018-07-01

    This article considers the terms prostitution, sex work, transactional sex, and survival sex, the logic of their deployment and utility to research concerned with people who are paid for sex, and HIV. The various names for paid sex in HIV research are invested in strategically differentiated positionings of people who receive payment and emphasize varying degrees of choice. The terminologies that seek to distinguish a range of economically motivated paid sex practices from sex work are characterized by an emphasis on the local and the particular, efforts to evade the stigma attached to the labels sex worker and prostitute, and an analytic prioritizing of culture. This works to bestow cultural legitimacy on some locally specific forms of paid sex and positions those practices as artifacts of culture rather than economy. This article contends that, in HIV research in particular, it is necessary to be cognizant of ways the deployment of alternative paid sex categories relocates and reinscribes stigma elsewhere. While local identity categories may be appropriate for program implementation, a global category is necessary for planning and funding purposes and offers a purview beyond that of isolated local phenomena. We argue that "sex work" is the most useful global term for use in research into economically motivated paid sex and HIV, primarily because it positions paid sex as a matter of labor, not culture or morality.

  15. Same Sex Marriage and the Perceived Assault on Opposite Sex Marriage

    OpenAIRE

    Dinno, Alexis; Whitney, Chelsea

    2013-01-01

    BACKGROUND: Marriage benefits both individuals and societies, and is a fundamental determinant of health. Until recently same sex couples have been excluded from legally recognized marriage in the United States. Recent debate around legalization of same sex marriage has highlighted for anti-same sex marriage advocates and policy makers a concern that allowing same sex couples to marry will lead to a decrease in opposite sex marriages. Our objective is to model state trends in opposite sex mar...

  16. Sex, Sexuality, Sexting, and SexEd: Adolescents and the Media

    Science.gov (United States)

    Brown, Jane D.; Keller, Sarah; Stern, Susannah

    2009-01-01

    The traditional media (television, radio, movies, magazines) and new, digital media (the Internet, Social Networking Sites such as Facebook and Myspace, and cell phones) have become important sex educators for adolescents. Adolescents in the United States spend six to seven hours a day with some form of media, often using more than one kind…

  17. Sex and Prevention Concerns for Positive People

    Science.gov (United States)

    ... with any comments or concerns. February 17, 2011 Sex and prevention concerns for positive people Facebook Twitter ... partner, and vice versa. The reality of safer sex You put yourself at risk for infections through ...

  18. Curious Sex Ratios and Cytoplasmic Genes

    Indian Academy of Sciences (India)

    instances of curious sex ratios exemplify an important principle: the fitness ..... markable transition - the whole means of sex determination has changed. No longer ... to the cytoplasmic symbiont is self-evident; the symbionts simply increase the.

  19. The Teacher and Sex Role Stereotyping

    Science.gov (United States)

    Juhasz, Anne McCreary

    1974-01-01

    In this article, selected research findings are presented on sex role learning, sex role stereotyping, in general and in the school setting, the effect of such stereotyping on the student, and some suggestions for the teacher. (Author/JA)

  20. Conservation of sex chromosomes in lacertid lizards

    Czech Academy of Sciences Publication Activity Database

    Rovatsos, M.; Vukič, J.; Altmanová, M.; Johnson Pokorná, Martina; Moravec, J.; Kratochvíl, L.

    2016-01-01

    Roč. 25, č. 13 (2016), s. 3120-3126 ISSN 0962-1083 Institutional support: RVO:67985904 Keywords : lizards * molecular sex ing * reptiles * sex chromosomes Subject RIV: EG - Zoology Impact factor: 6.086, year: 2016

  1. Sex differences in intracranial arterial bifurcations

    DEFF Research Database (Denmark)

    Lindekleiv, Haakon M; Valen-Sendstad, Kristian; Morgan, Michael K

    2010-01-01

    . The female preponderance is usually explained by systemic factors (hormonal influences and intrinsic wall weakness); however, the uneven sex distribution of intracranial aneurysms suggests a possible physiologic factor-a local sex difference in the intracranial arteries....

  2. SEX DETERMINATION FROM FEMORAL HEAD DIAMETERS IN ...

    African Journals Online (AJOL)

    hi-tech

    2000-03-01

    Mar 1, 2000 ... In medico-legal cases where sophisticated methods of sex determination is lacking, these ... scientific methods(3). Using the visual method ... between the sexes and the values of the right and left femoral head diameters.

  3. Sexing the Brain: The Science and Pseudoscience of Sex Differences

    Directory of Open Access Journals (Sweden)

    Lesley J. Rogers

    2010-06-01

    Full Text Available A recent upsurge in unitary biological explanations for gender differences in behavior (i.e. that they are “hard-wired” in the genetic code, put forward not only in books written for a general audience but also in scientific papers, makes it important to examine the fallacies of these ideas. Such genetic and hormonal explanations of human behavior, formulated with little consideration of the influences of experience, and often without taking experience into account at all, are part of a new wave of genetic explanations for a broad range of human behavior, as explained in the paper. These ideas are far from new; moreover, they are pseudoscientific and are used for political influence under the guise of science. They are a conservative social force that maintains social and educational inequalities between women and men. This paper explains that causal explanations of differences between the sexes are of two completely different types: unitary (genetic determinist versus interactive explanations. The false reasoning used to support genetic determinist explanations of sex differences in behavior is discussed. To illustrate what biology really tells us about gender differentiation, the paper discusses the interactive roles of genetic, hormonal and environmental influences on the development of gender differences. These interactions are illustrated using two model biological systems (e.g. the intertwined influences of genes, sex hormones and experience on the development of sex differences in behavior in rats, and sex differences in neuronal connections in chickens. There is plenty of scientific evidence to show the complex interactive, and ever changing, influences of experience and genes that take place as an organism develops and throughout its life. Malleability of brain and behavior can be shown clearly using animal models, and the processes involved apply also to the development of brain and behavior in humans. We diminish our understanding

  4. Abnormal sex chromosome constitution and longitudinal growth

    DEFF Research Database (Denmark)

    Aksglaede, Lise; Skakkebaek, Niels E; Juul, Anders

    2008-01-01

    Growth is a highly complex process regulated by the interaction between sex steroids and the GH IGF-axis. However, other factors such as sex chromosome-related genes play independent roles.......Growth is a highly complex process regulated by the interaction between sex steroids and the GH IGF-axis. However, other factors such as sex chromosome-related genes play independent roles....

  5. Sex work, immigration and social difference

    OpenAIRE

    Ham, Julie

    2017-01-01

    Public discourses around ‘migrant sex workers’ are often more confident about what migrant sex workers signify morally (i.e. vulnerability, criminality) but are less clear about who the ‘migrant’ is. This thesis interrogates the implications of the ‘migrant sex worker’ category based on semi-structured interviews with 65 immigrant, migrant and racialised women in sex work and two support staff in Melbourne, Australia and Vancouver, Canada during 2013–2014. Specifically, I employ an intersecti...

  6. Analyzing Medical Students' Definitions of Sex

    Science.gov (United States)

    Talley, Heather; Cho, Janice; Strassberg, Donald S.; Rullo, Jordan E.

    2016-01-01

    An inaccurate definition of what constitutes sex can negatively impact the sexual health and wellbeing of patients. This study aimed to determine which behaviors medical students consider to be sex. Survey questions about various sexual behaviors were administered to medical students. All participants agreed that penile-vaginal penetration is sex.…

  7. More on the New Sex Education.

    Science.gov (United States)

    Kasun, Jacqueline

    1980-01-01

    Replies to Paul V. Crosbie's criticisms. Argues that: reports of teenage sexuality and pregnancy are exaggerated; sex education programs encourage acceptance of every form of sexual expression; parents cannot always control their children's participation in sex education; and teachers are not equipped to teach sex education in a neutral fashion.…

  8. Sex Ideologies in China: Examining Interprovince Differences.

    Science.gov (United States)

    Hu, Yang

    2016-01-01

    In recent decades, premarital sex, extramarital sex, and homosexuality have become increasingly visible in China, leading scholars to claim that a national "sex revolution" is under way. However, China's internal sociocultural diversity calls this nation-level generalization into question. How do sex ideologies vary across China's distinct provinces? To what extent are interprovince variations in sex ideologies associated with distinct macrolevel social factors in China? In this research, data from the 2010 China General Social Survey and the 2011 Chinese Statistics Yearbook were analyzed using multilevel models to test four contending theories of interprovince differences in sex ideologies in China: modernization, Westernization, deindustrialization, and the "rice theory." The modernization theory was unsupported by the results, as socioeconomic development is not significantly associated with sex ideologies. Higher levels of deindustrialization and Westernization were associated with less traditional sex ideologies, but the strength of association varied across the domains of premarital sex, extramarital sex, and homosexuality. The rice theory was consistently supported, as the distinction between rice and wheat agriculture explained up to 30% of the province-level variance in sex ideologies. The findings underline the roles of both long-standing geographic differences and recent social changes in shaping China's ideational landscape of sex.

  9. Sex Role Development in Early Adolescence.

    Science.gov (United States)

    Wittig, Michele Andrisin

    1983-01-01

    Research involving adolescent identification with and development of sex roles is reviewed in the areas of cognitive skills and personality traits, theories of sex role development, and minority group adolescent sex role development. Emerging issues and educational implications in these areas are discussed. (CJ)

  10. Sexual Stratification and Sex-Role Socialization

    Science.gov (United States)

    VanFossen, Beth Ensiminger

    1977-01-01

    Data on sex-role values of a sample of college women are examined to ascertain the effect of family structure, social class, and religion on sex-role values, and to support a structural theory of sex-role socialization. (Author)

  11. The Promise of Single-Sex Classes

    Science.gov (United States)

    Stotsky, Sandra

    2012-01-01

    Despite the enthusiasm and the absence of definitive research on the pros and cons of single-sex classes, a 2011 article in Science, titled "The Pseudoscience of Single-Sex Schooling," by a new organization called American Council for CoEducational Schooling (ACCES) came out with the astonishing conclusion that single-sex education is…

  12. The Advantages of Single-Sex Education

    Science.gov (United States)

    Hughes, Teresa A.

    2006-01-01

    Traditionally, single-sex education has been provided in the form of private schooling. Title IX regulations have loosened as a result of the No Child Left Behind Legislation; therefore, public school districts now have the legal right to create single-sex classes or single-sex schools if they deem it to be in the best interest of their students.…

  13. Sex Differences in Assertiveness in College Students

    Science.gov (United States)

    Stebbins, Charles; And Others

    1977-01-01

    Validates the "College Self-Expression Scale." Shows that females are significantly more assertive, and that in one of the criterion situations each sex was significantly more assertive toward members of the same sex than members of the opposite sex. (RL)

  14. HIV and safe, healthy sex.

    Science.gov (United States)

    1997-01-01

    If a woman wants to become pregnant, how can she reduce her risk of HIV and other sexually transmitted infections? When a young man is growing up and worried about his future, how can you expect him to be concerned about HIV? Many HIV prevention projects focus on HIV and other sexually transmitted infections without considering people's broader reproductive and sexual health concerns. HIV prevention depends on people being able to make choices about their sexual behavior. This means understanding how their bodies work, knowing what choices are available to them, and having the confidence and skills to discuss and make changes in their sexual and reproductive lives. HIV educators, family planning workers, youth counselors, and others need to be able to respond to a range of questions and concerns in a sensitive and supportive way. This special, double issue of AIDS Action provides basic facts about the reproductive system, fertility, sexually transmitted infections and contraception, and looks at the links between HIV, sex, and reproduction. Talking about sex can be difficult. Sex is a private matter and people often feel embarrassed talking about it. This issue also contains tips for communication and activities to find out what people know already and help them learn. You may find that not everything in this issue is necessary for the people you are working with. This is a 'pick and mix' issue for you to pick out what is useful, adapting it if you wish. full text

  15. MODERN TEENAGER (HIGHLANDER AND SEX

    Directory of Open Access Journals (Sweden)

    Oksana Fedyk

    2015-04-01

    Full Text Available The age at which you can start or be sexually active - a very interesting question, which concerned not only parents, but also psychologists. Usually, you can not answer the question of when and to whom to start having sex. However, there are certain statistics that the average age of sexual debut in adolescents - is 15 years for girls and 14 for boys. Now we are talking about European society, about what is happening in Ukraine, particularly in mountainous areas. The fact that the willingness in principle to sexual intercourse is associated with physiological aspects. There is a notion in sexology - sexual constitution. There are several factors play a role, of course, one of which is constitutional, but not always, psychological maturity and sexual constitution, rather, because of the need for sexual constitution in holding intercourse can match. That is, some teens may be physiologically ready for sexual intercourse at 12-13 years, but the question arises: Are they psychologically? And probably we can not give a definite answer to this question, because curiosity taboo in society, which in the majority rejects teen sex, pushing them into early sexual relations. Nevertheless, probably still age readiness and psychological and physiological - is 18-19 years if we are talking about teen sex.

  16. [Does really sex addiction exist?].

    Science.gov (United States)

    Echeburúa, Enrique

    2012-01-01

    Hypersexual Disorder has been proposed as a new psychiatric disorder for DSM-V, characterized by an increased frequency and intensity of sexually motivated fantasies, arousal, urges, and enacted behavior in association with an impulsivity component. Excessive appetitive and consummatory behaviors, including hypersexuality, can become a non-chemical addiction. Sexual addiction afflicts people having paraphilic or nonparaphilic behaviors associated with progressive risk-taking sexual behaviors, escalation or progression of sexual behaviors (tolerance), loss of control and significant adverse psychosocial consequences, such as unplanned pregnancy, pair-bond dysfunction, marital separation, financial problems and sexually transmitted diseases including HIV. The most common behaviors involved in sexual addiction are fantasy sex, compulsive masturbation, pornography, cybersex, voyeuristic sex, anonymous sex and multiple sexual partners. These behaviors are intended to reduce anxiety and other dysphoric affects (e.g., shame and depression). Axis I psychiatric diagnosis, especially mood disorders, psychoactive substance abuse disorders and attention deficit hyperactivity disorders, are common comorbid disorders with sexual addiction. There are significant gaps in the current scientific knowledge base regarding the clinical course, development risk factors and family history and data on women with sexual addiction are lacking.

  17. Sex

    OpenAIRE

    Webber, Jonathan

    2009-01-01

    The sexual domain is unified only by the phenomenal quality of the occurrence of the desires, activities, and pleasures it includes. There is no conceptual restriction on the range of intentional objects those desires, activities, and pleasures can take. Neither is there good conceptual reason to privilege any class of them as paradigmatic. Since the quality unifying the sexual is not morally significant, the morality of sexuality is no different from morality in general. The view that partic...

  18. Local offspring density and sex ratio affect sex allocation in the great tit

    NARCIS (Netherlands)

    Michler, Stephanie P. M.; Nicolaus, Marion; van der Velde, Marco; Radersma, Reinder; Ubels, Richard; Both, Christiaan; Komdeur, Jan; Tinbergen, Joost M.

    2013-01-01

    The expected fitness gain for offspring of a given sex may depend on local population sex ratio and density. Knowing the influence of such social factors on brood sex ratios may contribute considerably to the understanding of sex allocation in higher vertebrates. For 3 consecutive years, we

  19. A Theoretical Analysis of Sex Differences In Same-Sex Friendships.

    Science.gov (United States)

    Barth, Robert J.; Kinder, Bill N.

    1988-01-01

    Investigates sex differences in same-sex friendships of 312 undergraduate students in terms of the intersection and social penetration model of relationship development, and Bem's theory of sex role orientation. Finds significant sex-related differences in depth, duration, and involvement. (FMW)

  20. Sex Education and Sex Stereotypes: Theory and Practice. Working Paper No. 198.

    Science.gov (United States)

    Stubbs, Margaret L.

    This paper presents an explanation of practitioners' reactions to sex equitable sex education. Several constraints can prohibit practitioners from engaging in sex equitable sex education: (1) lack of community support; (2) lack of expertise in human sexuality education; (3) vagueness of school committee views; and (4) lack of answers to logistical…

  1. Sex and the Filipino adolescent.

    Science.gov (United States)

    Anigan, G

    1979-01-01

    Very little is known about Filipino adolescents. Professional opinion varies enormously as to what is to be considered normal and abnormal. 1 aspect of adolescence which is agreed upon is that it is a period of great change. What brings on puberty is a controversial topic. Nutrition and genetic inheritance have been found to affect the age at which menstruation begins. Environment plays a large role in emotional and social growth. Filipino sex education is rather haphazard. A study of over 5000 adolescents in 1972-73 showed that sexual information was gained principally from pornographic literature, movies, television and friends. Boys also watched strip-tease acts and went to houses of prostitution. 2/3 of males and 3/4 of females had had crushes, while over 1/2 of both sexes had "gone steady" by age 16. Boys fell in love more often and less seriously than did girls. Girls generally have more adjustment problems in adolescence than do boys. Among Filipino adolescents, dating is the top ranking sex-related problem. Both sexes are concerned with what is the proper behavior in dating. Dating is an erotic as well as a social experience for Filipino adolescents. Premarital sexual activity is now receiving more tolerance. Urban males are less concerned with the virginity of their brides, but adults are still intolerant. Perhaps the present generation of adolescents is the harbinger of a new sexual morality. Fertility rates for 15-19 year olds have been declining since the 1960s. However, among adolescents with problems, pregnancy ranks high. Homosexuals are more visible in the Philippines now, as they are being more tolerated. Adolescent fertility is the last great challenge in the family planning field. Problems are unwillingness of counselors to participate in studies and a paucity of basic research. 3 studies are now being conducted in the Metro Manila area. Peer counseling and multiservice centers which provide relative anonymity are 2 approaches which shoul d be

  2. Sex differences in same-sex direct aggression and sociosexuality: the role of risky impulsivity.

    Science.gov (United States)

    Cross, Catharine P

    2010-12-23

    Sex differences in same-sex direct aggression and sociosexuality are among the most robust in the literature. The present article evaluated the hypothesis that both can be explained by a sex difference in the willingness to take impulsive risks. Self-report data were gathered from 3,775 respondents (1,514 female) on same-sex aggression, sociosexuality, and risky impulsivity. Risky impulsivity was higher for men than for women (d = .34) and path analysis showed it to be a common cause of same-sex aggression and sociosexuality for both sexes. However, it did not completely mediate the sex differences in same-sex aggression and sociosexuality. The results suggest that same-sex aggression and sociosexual behavior share a common psychological mechanism, but that fully explaining sex differences in aggression requires a more sensitive assay of impulsive risk and a consideration of dyadic processes.

  3. Sex Differences in Same-Sex Direct Aggression and Sociosexuality: The Role of Risky Impulsivity

    Directory of Open Access Journals (Sweden)

    Catharine P. Cross

    2010-10-01

    Full Text Available Sex differences in same-sex direct aggression and sociosexuality are among the most robust in the literature. The present article evaluated the hypothesis that both can be explained by a sex difference in the willingness to take impulsive risks. Self-report data were gathered from 3,775 respondents (1,514 female on same-sex aggression, sociosexuality, and risky impulsivity. Risky impulsivity was higher for men than for women (d = .34 and path analysis showed it to be a common cause of same-sex aggression and sociosexuality for both sexes. However, it did not completely mediate the sex differences in same-sex aggression and sociosexuality. The results suggest that same-sex aggression and sociosexual behavior share a common psychological mechanism, but that fully explaining sex differences in aggression requires a more sensitive assay of impulsive risk and a consideration of dyadic processes.

  4. Governing sex work in the city

    OpenAIRE

    Laing, Mary; Cook, Ian

    2014-01-01

    Sex work is often constructed as an urban "problem". As a result, sex workers, clients and the spaces in which people buy or sell sex are frequently the subject of intervention from those governing cities. This paper considers the ways in which problems and solutions are framed in the wider governance of sex work in cities in the global north. It draws on a range of academic literature to show how the urban governance of sex work takes relational and territorial forms. Governance is relationa...

  5. Screening Sex: revelando e dissimulando o sexo Screening Sex

    Directory of Open Access Journals (Sweden)

    Linda Williams

    2012-06-01

    Full Text Available Neste texto, procura-se contar a história da exibição do sexo em filmes majoritariamente produzidos nos Estados Unidos no período de quase um século. Ao se perguntar quando, porque e como os Estados Unidos se transformaram de uma cultura que não exibia o sexo em uma que o exibe, a autora insiste no duplo significado do verbo screen (tanto como uma revelação quanto uma dissimulação. Exibir é revelar em uma tela. Mas um segundo e igualmente importante significado, como diz o dicionário é "proteger ou esconder atrás de uma tela". Os filmes tanto revelam como escondem. O artigo analisa a forma como mudanças sociais ocorridas nos Estados Unidos, como, por exemplo, a Revolução sexual dos anos 60 e novas visões a respeito da sexualidade, possibilitaram novas maneiras de representação do sexo no cinema, reorganizando a relação entre o público e o privado. O artigo se pergunta também sobre como nossos corpos e sentidos reagem ao encontro com o sexo na tela, introduzindo a ideia de "saber carnal" (carnal knowledge.In this paper, we try to tell the history of the exhibition of sex in movies mainly produced in the United States in almost a century. Asking when, why and how the United States became - from a culture that did not exhibit sex - into a culture that exhibits it, the author insists in the double sense of the verb to screen (as both a revelation and a dissimulation. To exhibit is to reveal in a screen. But another, and important, sense, as says the dictionary, is "to protect or hide behind a screen". Movies show as well as they reveal. The paper analyzes the way social change in the United States, for example the sexual revolution of the sixties and new views on sexuality allowed new ways of representing sex in the movies, creating a new relation between public and private. The paper also asks how our bodies and senses react to sex in the screen, introducing the idea of "carnal knowledge".

  6. Sex tourism among Chinese men who have sex with men: a cross-sectional observational study.

    OpenAIRE

    Mao, J; Tang, W; Liu, C; Wong, NS; Tang, S; Wei, C; Tucker, JD

    2018-01-01

    Sex tourism among men who have sex with men (MSM) may exacerbate transmission of HIV and other sexually transmitted infections (STIs). Sex tourism is defined as purchasing sex with gifts or money outside of one's hometown. Our objective was to characterize the frequency, socio-demographic characteristics, and sexual risk behaviors among Chinese MSM sex tourists. An online, cross-sectional survey for high-risk MSM throughout China was conducted in November 2015 covering sociodemographic charac...

  7. Same sex marriage and the perceived assault on opposite sex marriage.

    Science.gov (United States)

    Dinno, Alexis; Whitney, Chelsea

    2013-01-01

    Marriage benefits both individuals and societies, and is a fundamental determinant of health. Until recently same sex couples have been excluded from legally recognized marriage in the United States. Recent debate around legalization of same sex marriage has highlighted for anti-same sex marriage advocates and policy makers a concern that allowing same sex couples to marry will lead to a decrease in opposite sex marriages. Our objective is to model state trends in opposite sex marriage rates by implementation of same sex marriages and other same sex unions. Marriage data were obtained for all fifty states plus the District of Columbia from 1989 through 2009. As these marriage rates are non-stationary, a generalized error correction model was used to estimate long run and short run effects of same sex marriages and strong and weak same sex unions on rates of opposite sex marriage. We found that there were no significant long-run or short run effects of same sex marriages or of strong or weak same sex unions on rates of opposite sex marriage. A deleterious effect on rates of opposite sex marriage has been argued to be a motivating factor for both the withholding and the elimination of existing rights of same sex couples to marry by policy makers-including presiding justices of current litigation over the rights of same sex couples to legally marry. Such claims do not appear credible in the face of the existing evidence, and we conclude that rates of opposite sex marriages are not affected by legalization of same sex civil unions or same sex marriages.

  8. Same Sex Marriage and the Perceived Assault on Opposite Sex Marriage

    Science.gov (United States)

    Dinno, Alexis; Whitney, Chelsea

    2013-01-01

    Background Marriage benefits both individuals and societies, and is a fundamental determinant of health. Until recently same sex couples have been excluded from legally recognized marriage in the United States. Recent debate around legalization of same sex marriage has highlighted for anti-same sex marriage advocates and policy makers a concern that allowing same sex couples to marry will lead to a decrease in opposite sex marriages. Our objective is to model state trends in opposite sex marriage rates by implementation of same sex marriages and other same sex unions. Methods and Findings Marriage data were obtained for all fifty states plus the District of Columbia from 1989 through 2009. As these marriage rates are non-stationary, a generalized error correction model was used to estimate long run and short run effects of same sex marriages and strong and weak same sex unions on rates of opposite sex marriage. We found that there were no significant long-run or short run effects of same sex marriages or of strong or weak same sex unions on rates of opposite sex marriage. Conclusion A deleterious effect on rates of opposite sex marriage has been argued to be a motivating factor for both the withholding and the elimination of existing rights of same sex couples to marry by policy makers–including presiding justices of current litigation over the rights of same sex couples to legally marry. Such claims do not appear credible in the face of the existing evidence, and we conclude that rates of opposite sex marriages are not affected by legalization of same sex civil unions or same sex marriages. PMID:23776536

  9. Sex Differences in Human and Animal Toxicology.

    Science.gov (United States)

    Gochfeld, Michael

    2017-01-01

    Sex, the states of being female or male, potentially interacts with all xenobiotic exposures, both inadvertent and deliberate, and influences their toxicokinetics (TK), toxicodynamics, and outcomes. Sex differences occur in behavior, exposure, anatomy, physiology, biochemistry, and genetics, accounting for female-male differences in responses to environmental chemicals, diet, and pharmaceuticals, including adverse drug reactions (ADRs). Often viewed as an annoying confounder, researchers have studied only one sex, adjusted for sex, or ignored it. Occupational epidemiology, the basis for understanding many toxic effects in humans, usually excluded women. Likewise, Food and Drug Administration rules excluded women of childbearing age from drug studies for many years. Aside from sex-specific organs, sex differences and sex × age interactions occur for a wide range of disease states as well as hormone-influenced conditions and drug distribution. Women have more ADRs than men; the classic sex hormone paradigm (gonadectomy and replacement) reveals significant interaction of sex and TK including absorption, distribution, metabolisms, and elimination. Studies should be designed to detect sex differences, describe the mechanisms, and interpret these in a broad social, clinical, and evolutionary context with phenomena that do not differ. Sex matters, but how much of a difference is needed to matter remains challenging.

  10. [Mobile genetic elements in plant sex evolution].

    Science.gov (United States)

    Gerashchenkov, G A; Rozhnova, N A

    2010-11-01

    The most significant theories of the appearance and maintenance of sex are presented. However, in the overwhelming majority of existing theories, the problem of sex, which is the central problem of evolutionary biology, is considered primarily through the prism of reproductive features of living organisms, whereas the issue of molecular driving forces of sexual reproduction id restricted to the possible role of mobile genetic elements (MGEs) in the appearance of sexual reproduction. The structural and functional significance of MGEs in the genomic organization of plants is illustrated. It is shown that MGEs could act as important molecular drivers of sex evolution in plants. The involvement of MGEs in the formation of sex chromosomes and possible participation in seeds-without-sex reproduction (apomixis) is discussed. Thus, the hypothesis on the active MGE participation in sex evolution is in good agreement with the modern views on pathways and directions of sex evolution in plants.

  11. Sex differences in heritability of BMI

    DEFF Research Database (Denmark)

    Schousboe, Karoline; Willemsen, Gonneke; Kyvik, Kirsten O

    2003-01-01

    pairs (including opposite sex pairs) aged 20-29 and 30-39 from eight different twin registries participating in the GenomEUtwin project. Quantitative genetic analyses were conducted and sex differences were explored. Variation in BMI was greater for women than for men, and in both sexes was primarily...... explained by additive genetic variance in all countries. Sex differences in the variance components were consistently significant. Results from analyses of opposite sex pairs also showed evidence of sex-specific genetic effects suggesting there may be some differences between men and women in the genetic...... factors that influence variation in BMI. These results encourage the continued search for genes of importance to the body composition and the development of obesity. Furthermore, they suggest that strategies to identify predisposing genes may benefit from taking into account potential sex specific effects....

  12. Sex work among men who have sex with men and transgender women in Bogotá.

    Science.gov (United States)

    Bianchi, Fernanda T; Reisen, Carol A; Zea, Maria Cecilia; Vidal-Ortiz, Salvador; Gonzales, Felisa A; Betancourt, Fabián; Aguilar, Marcela; Poppen, Paul J

    2014-11-01

    This qualitative study examined sex work among internally displaced male and transgender female sex workers in Bogotá, Colombia. Internal displacement has occurred in Colombia as a result of decades of conflict among armed groups and has created large-scale migration from rural to urban areas. Informed by the polymorphous model of sex work, which posits that contextual conditions shape the experience of sex work, we examined three main research questions. The first dealt with how internal displacement was related to the initiation of sex work; the second concerned the effect of agency on sex worker satisfaction; and the third examined how sex work in this context was related to HIV and other risks. Life history interviews were conducted with 26 displaced individuals who had done sex work: 14 were men who have sex with men and 12 were transgender women (natal males). Findings revealed that many participants began doing sex work in the period immediately after displacement, because of a lack of money, housing, and social support. HIV risk was greater during this time due to limited knowledge of HIV and inexperience negotiating safer sex with clients. Other findings indicated that sex workers who exerted more control and choice in the circumstances of their work reported greater satisfaction. In addition, we found that although many sex workers insisted on condom use with clients, several noted that they would sometimes have unprotected sex for additional money. Specific characteristics affecting the experience of sex work among the transgender women were also discussed.

  13. Genetic sex determination and extinction.

    Science.gov (United States)

    Hedrick, Philip W; Gadau, Jürgen; Page, Robert E

    2006-02-01

    Genetic factors can affect the probability of extinction either by increasing the effect of detrimental variants or by decreasing the potential for future adaptive responses. In a recent paper, Zayed and Packer demonstrate that low variation at a specific locus, the complementary sex determination (csd) locus in Hymenoptera (ants, bees and wasps), can result in a sharply increased probability of extinction. Their findings illustrate situations in which there is a feedback process between decreased genetic variation at the csd locus owing to genetic drift and decreased population growth, resulting in an extreme type of extinction vortex for these ecologically important organisms.

  14. Men who advertise for sex.

    Science.gov (United States)

    Lumby, M E

    1978-01-01

    This content analysis of 1,111 paid ads in the Advocate identifies 17 self-descriptive categories in the "Personals" (PER) and "Models, Masseurs, and Escorts" (MME) sections of the "Trader Dick" supplement. Advertisers place primary emphases on sex and masculinity. Among MME, youthfulness, handsomeness, and sexiness are important, promoting versatility in place of specificity when mentioning sexual acts. PER advertisers, however, indicate concerns about age, race, and finding lovers. They also detail specific sexual interests and reject a variety of unacceptable behaviors.

  15. Sex differences in human epilepsy.

    Science.gov (United States)

    Savic, Ivanka

    2014-09-01

    In the majority of neuropsychiatric conditions, marked gender-based differences have been found in the epidemiology, clinical manifestations, and therapy of disease. Emerging data suggest that gender differences exist also in the epidemiology, and pathophysiology of epilepsy. The present review summarizes the current information regarding gender and epilepsy. These differences are regarded from the perspective of innate sex differences in cerebral morphology, structural and functional connections, and assuming that these differences may render men and women differently vulnerable to epileptogenicity. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Sex-Role Portrayals of Selected Female Television Characters.

    Science.gov (United States)

    Goff, David H.; And Others

    1980-01-01

    Examines the relationship between both the sex-role and the sex of viewers and viewer perception of the sex-role depicted by five female characters in prime-time television programs. Perception of character sex-role was significantly related to subject sex-role, yet unrelated to subject sex or gender. (MER)

  17. Technology, normalisation and male sex work.

    Science.gov (United States)

    MacPhail, Catherine; Scott, John; Minichiello, Victor

    2015-01-01

    Technological change, particularly the growth of the Internet and smart phones, has increased the visibility of male escorts, expanded their client base and diversified the range of venues in which male sex work can take place. Specifically, the Internet has relocated some forms of male sex work away from the street and thereby increased market reach, visibility and access and the scope of sex work advertising. Using the online profiles of 257 male sex workers drawn from six of the largest websites advertising male sexual services in Australia, the role of the Internet in facilitating the normalisation of male sex work is discussed. Specifically we examine how engagement with the sex industry has been reconstituted in term of better informed consumer-seller decisions for both clients and sex workers. Rather than being seen as a 'deviant' activity, understood in terms of pathology or criminal activity, male sex work is increasingly presented as an everyday commodity in the market place. In this context, the management of risks associated with sex work has shifted from formalised social control to more informal practices conducted among online communities of clients and sex workers. We discuss the implications for health, legal and welfare responses within an empowerment paradigm.

  18. Searching for the Advantages of Virus Sex

    Science.gov (United States)

    Turner, Paul E.

    2003-02-01

    Sex (genetic exchange) is a nearly universal phenomenon in biological populations. But this is surprising given the costs associated with sex. For example, sex tends to break apart co-adapted genes, and sex causes a female to inefficiently contribute only half the genes to her offspring. Why then did sex evolve? One famous model poses that sex evolved to combat Muller's ratchet, the mutational load that accrues when harmful mutations drift to high frequencies in populations of small size. In contrast, the Fisher-Muller Hypothesis predicts that sex evolved to promote genetic variation that speeds adaptation in novel environments. Sexual mechanisms occur in viruses, which feature high rates of deleterious mutation and frequent exposure to novel or changing environments. Thus, confirmation of one or both hypotheses would shed light on the selective advantages of virus sex. Experimental evolution has been used to test these classic models in the RNA bacteriophage φ6, a virus that experiences sex via reassortment of its chromosomal segments. Empirical data suggest that sex might have originated in φ6 to assist in purging deleterious mutations from the genome. However, results do not support the idea that sex evolved because it provides beneficial variation in novel environments. Rather, experiments show that too much sex can be bad for φ6 promiscuity allows selfish viruses to evolve and spread their inferior genes to subsequent generations. Here I discuss various explanations for the evolution of segmentation in RNA viruses, and the added cost of sex when large numbers of viruses co-infect the same cell.

  19. Bacterial sex in dental plaque.

    Science.gov (United States)

    Olsen, Ingar; Tribble, Gena D; Fiehn, Nils-Erik; Wang, Bing-Yan

    2013-01-01

    Genes are transferred between bacteria in dental plaque by transduction, conjugation, and transformation. Membrane vesicles can also provide a mechanism for horizontal gene transfer. DNA transfer is considered bacterial sex, but the transfer is not parallel to processes that we associate with sex in higher organisms. Several examples of bacterial gene transfer in the oral cavity are given in this review. How frequently this occurs in dental plaque is not clear, but evidence suggests that it affects a number of the major genera present. It has been estimated that new sequences in genomes established through horizontal gene transfer can constitute up to 30% of bacterial genomes. Gene transfer can be both inter- and intrageneric, and it can also affect transient organisms. The transferred DNA can be integrated or recombined in the recipient's chromosome or remain as an extrachromosomal inheritable element. This can make dental plaque a reservoir for antimicrobial resistance genes. The ability to transfer DNA is important for bacteria, making them better adapted to the harsh environment of the human mouth, and promoting their survival, virulence, and pathogenicity.

  20. Bacterial sex in dental plaque

    Directory of Open Access Journals (Sweden)

    Ingar Olsen

    2013-06-01

    Full Text Available Genes are transferred between bacteria in dental plaque by transduction, conjugation, and transformation. Membrane vesicles can also provide a mechanism for horizontal gene transfer. DNA transfer is considered bacterial sex, but the transfer is not parallel to processes that we associate with sex in higher organisms. Several examples of bacterial gene transfer in the oral cavity are given in this review. How frequently this occurs in dental plaque is not clear, but evidence suggests that it affects a number of the major genera present. It has been estimated that new sequences in genomes established through horizontal gene transfer can constitute up to 30% of bacterial genomes. Gene transfer can be both inter- and intrageneric, and it can also affect transient organisms. The transferred DNA can be integrated or recombined in the recipient's chromosome or remain as an extrachromosomal inheritable element. This can make dental plaque a reservoir for antimicrobial resistance genes. The ability to transfer DNA is important for bacteria, making them better adapted to the harsh environment of the human mouth, and promoting their survival, virulence, and pathogenicity.

  1. Sex differences in addictive disorders.

    Science.gov (United States)

    Fattore, Liana; Melis, Miriam; Fadda, Paola; Fratta, Walter

    2014-08-01

    Gender-dependent differences in the rate of initiation and frequency of misuse of addicting drugs have been widely described. Yet, men and women also differ in their propensity to become addicted to other rewarding stimuli (e.g., sex, food) or activities (e.g., gambling, exercising). The goal of the present review is to summarize current evidence for gender differences not only in drug addiction, but also in other forms of addictive behaviours. Thus, we first reviewed studies showing gender-dependent differences in drug addiction, food addiction, compulsive sexual activity, pathological gambling, Internet addiction and physical exercise addiction. Potential risk factors and underlying brain mechanisms are also examined, with particular emphasis given to the role of sex hormones in modulating addictive behaviours. Investigations on factors allowing the pursuit of non-drug rewards to become pathological in men and women are crucial for designing gender-appropriate treatments of both substance and non-substance addictions. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Why sex hormones matter for neuroscience: A very short review on sex, sex hormones, and functional brain asymmetries.

    Science.gov (United States)

    Hausmann, Markus

    2017-01-02

    Biological sex and sex hormones are known to affect functional cerebral asymmetries (FCAs). Men are generally more lateralized than women. The effect size of this sex difference is small but robust. Some of the inconsistencies in the literature may be explained by sex-related hormonal differences. Most studies focusing on neuromodulatory properties of sex hormones on FCAs have investigated women during the menstrual cycle. Although contradictions exist, these studies have typically shown that levels of estradiol and/or progesterone correlate with the degree of FCAs, suggesting that sex differences in FCAs partially depend on hormonal state and day of testing. The results indicate that FCAs are not fixed but are hormone dependent, and as such they can dynamically change within relatively short periods throughout life. Many issues raised in this Mini-Review refer not only to FCAs but also to other aspects of functional brain organization, such as functional connectivity within and between the cerebral hemispheres. Our understanding of sex differences in brain and behavior as well as their clinical relevance will improve significantly if more studies routinely take sex and sex hormones into account. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  3. Is Group Sex a Higher-Risk Setting for HIV and Other Sexually Transmitted Infections Compared With Dyadic Sex Among Men Who Have Sex With Men?

    NARCIS (Netherlands)

    van den Boom, Wijnand; Davidovich, Udi; Heuker, José; Lambers, Femke; Prins, Maria; Sandfort, Theo; Stolte, Ineke G.

    2016-01-01

    Group sex has been suggested as a potential high-risk setting for HIV and other sexually transmitted infections (STIs) among men who have sex with men (MSM). We investigated whether group sex is associated with lower condom use during anal sex and higher proportions of STIs compared with dyadic sex

  4. Sex differences and stress across the lifespan

    Science.gov (United States)

    Bale, Tracy L; Epperson, C Neill

    2015-01-01

    Sex differences in stress responses can be found at all stages of life and are related to both the organizational and activational effects of gonadal hormones and to genes on the sex chromosomes. As stress dysregulation is the most common feature across neuropsychiatric diseases, sex differences in how these pathways develop and mature may predict sex-specific periods of vulnerability to disruption and increased disease risk or resilience across the lifespan. The aging brain is also at risk to the effects of stress, where the rapid decline of gonadal hormones in women combined with cellular aging processes promote sex biases in stress dysregulation. In this Review, we discuss potential underlying mechanisms driving sex differences in stress responses and their relevance to disease. Although stress is involved in a much broader range of diseases than neuropsychiatric ones, we highlight here this area and its examples across the lifespan. PMID:26404716

  5. Sex differences and stress across the lifespan.

    Science.gov (United States)

    Bale, Tracy L; Epperson, C Neill

    2015-10-01

    Sex differences in stress responses can be found at all stages of life and are related to both the organizational and activational effects of gonadal hormones and to genes on the sex chromosomes. As stress dysregulation is the most common feature across neuropsychiatric diseases, sex differences in how these pathways develop and mature may predict sex-specific periods of vulnerability to disruption and increased disease risk or resilience across the lifespan. The aging brain is also at risk to the effects of stress, where the rapid decline of gonadal hormones in women combined with cellular aging processes promote sex biases in stress dysregulation. In this Review, we discuss potential underlying mechanisms driving sex differences in stress responses and their relevance to disease. Although stress is involved in a much broader range of diseases than neuropsychiatric ones, we highlight here this area and its examples across the lifespan.

  6. A reconfiguration of the sex trade

    DEFF Research Database (Denmark)

    Elmes, Jocelyn; Skovdal, Morten; Nhongo, Kundai

    2017-01-01

    a unique opportunity to study community perceptions of the impact of socio-economic upheaval on the sex trade. We conducted focus group discussions with 122 community members in rural eastern Zimbabwe in January-February 2009. Groups were homogeneous by gender and occupation and included female sex workers......Understanding the dynamic nature of sex work is important for explaining the course of HIV epidemics. While health and development interventions targeting sex workers may alter the dynamics of the sex trade in particular localities, little has been done to explore how large-scale social...... and structural changes, such as economic recessions–outside of the bounds of organizational intervention–may reconfigure social norms and attitudes with regards to sex work. Zimbabwe’s economic collapse in 2009, following a period (2000–2009) of economic decline, within a declining HIV epidemic, provides...

  7. Sex differences in heritability of neck Pain

    DEFF Research Database (Denmark)

    Fejer, René; Hartvigsen, Jan; Kyvik, Kirsten Ohm

    2006-01-01

    Experimental studies have suggested biological factors as a possible explanation for gender disparities in perception of pain. Recently, heritability of liability to neck pain (NP) has been found to be statistically significantly larger in women compared to men. However, no studies have been...... conducted to determine whether the sex differences in heritability of NP are due to sex-specific genetic factors. Data on lifetime prevalence of NP from a population-based cross-sectional survey of 33,794 Danish twins were collected and age-stratified univariate biometrical modeling using sex......-limitation models was performed based on 10,605 dizygotic (DZ) twins of opposite sex to estimate the qualitative sex differences. In a full sex-limitation model the genetic component in females were higher than in males, but the genetic and the shared environmental correlations were equal to what is normally...

  8. Patpong, entre sexe et commerce.

    Directory of Open Access Journals (Sweden)

    Sébastien Roux

    2010-03-01

    Full Text Available Le tourisme dit « sexuel » est aujourd’hui décrié comme une forme de tourisme international immoral, un dysfonctionnement grave de la mondialisation appelant une réaction politique contre « l’exploitation sexuelle » dont seraient victimes des millions de femmes et d’enfants. Pourtant, derrière l’apparente évidence du « tourisme sexuel » comme expression de sens commun, rares sont les enquêtes qui explicitent la réalité concrète des échanges prostitutionnels. En adoptant une démarche ethnographique, l’article décrit le fonctionnement de Patpong, un quartier rouge de Bangkok dédié à une clientèle internationale. Par la description des offres disponibles, des revenus générés, des codes et des pratiques, la complexité de l’espace réapparaît. Il s’agit de donner à voir la réalité des échanges pour interroger l’articulation entre commerce et sexualité. L’analyse ethnographique du tourisme sexuel permet ainsi de souligner la diversité des pratiques et de rappeler que les formes les plus visibles — et les plus commentées — d’échanges prostitutionnels éclipsent trop souvent une pluralité d’expériences qui participe pourtant au succès de ces ruelles mondialement connues. So-called sex tourism is condemned as an immoral form of international tourism, a serious failure of globalization requiring political action against the “sexual exploitation” suffered by millions of women and children. Yet behind the common and seemingly evident understanding of “sexual tourism,” few studies have focused on the actual reality of such relations. Based on an ethnographic study, this article presents the structure of Patpong, a red-light district of Bangkok dedicated to international tourism. First, the article aims to briefly present the historical development of Patpong. This peculiar space is intrinsically linked to sex tourism, as these world-renowned streets expanded since the mid-60s to

  9. Gender in Winterson's Sexing the Cherry

    OpenAIRE

    Kintzele, Paul

    2010-01-01

    In his article "Gender in Winterson's Sexing the Cherry" Paul Kintzele examines the ways in which Jeanette Winterson's 1989 novel explores and critiques aspects of gender and sexuality. While acknowledging the importance of the performance theory of gender that derives from the work of Judith Butler, Kintzele contends that such an approach must be complemented with a psychoanalytic approach that insists on a particular distinction between sex and gender. Although some scholars map the sex/gen...

  10. Sex tourism among Chinese men who have sex with men: a cross-sectional observational study.

    Science.gov (United States)

    Mao, Jessica; Tang, Weiming; Liu, Chuncheng; Wong, Ngai Sze; Tang, Songyuan; Wei, Chongyi; Tucker, Joseph D

    2018-03-02

    Sex tourism among men who have sex with men (MSM) may exacerbate transmission of HIV and other sexually transmitted infections (STIs). Sex tourism is defined as purchasing sex with gifts or money outside of one's hometown. Our objective was to characterize the frequency, socio-demographic characteristics, and sexual risk behaviors among Chinese MSM sex tourists. An online, cross-sectional survey for high-risk MSM throughout China was conducted in November 2015 covering sociodemographic characteristics, sexual risk behaviors, and sex tourism. Univariate and multivariable logistic regressions were performed to identify correlates of sex tourism. The mean MSM HIV prevalence of sex tourism journey origins and destinations were compared. Of 1189 MSM who completed the survey, 62 (5%) men identified as sex tourists; among these sex tourists, twenty (32%) traveled primarily to purchase sex and the remainder purchased sex while traveling for another purpose. There was minimal socio-demographic and behavioral difference between the two groups. In multivariable analyses, adjusting for age and income, sex tourism was correlated with high-risk sexual behaviors, higher income (aOR 4.44, 95%CI 1.77-11.18) and living with HIV (aOR 2.79, 95%CI 1.03-7.55). Sex tourism was more often from locations with lower to higher MSM HIV prevalence (mean = 4.47, SD = 2.01 versus mean = 6.86, SD = 5.24). MSM sex tourists were more likely to have risky sexual behaviors and travel to locations with a higher HIV prevalence. MSM sex tourists may be part of core groups that are disproportionately responsible for MSM HIV transmission. Enhanced surveillance and interventions tailored to MSM sex tourists should be considered.

  11. Same-Sex and Different-Sex Cohabiting Couple Relationship Stability.

    Science.gov (United States)

    Manning, Wendy D; Brown, Susan L; Stykes, J Bart

    2016-08-01

    Relationship stability is a key indicator of well-being, but most U.S.-based research has been limited to different-sex couples. The 2008 panel of the Survey of Income and Program Participation (SIPP) provides an untapped data resource to analyze relationship stability of same-sex cohabiting, different-sex cohabiting, and different-sex married couples (n = 5,701). The advantages of the SIPP data include the recent, nationally representative, and longitudinal data collection; a large sample of same-sex cohabitors; respondent and partner socioeconomic characteristics; and identification of a state-level indicator of a policy stating that marriage is between one man and one woman (i.e., DOMA). We tested competing hypotheses about the stability of same-sex versus different-sex cohabiting couples that were guided by incomplete institutionalization, minority stress, relationship investments, and couple homogamy perspectives (predicting that same-sex couples would be less stable) as well as economic resources (predicting that same-sex couples would be more stable). In fact, neither expectation was supported: results indicated that same-sex cohabiting couples typically experience levels of stability that are similar to those of different-sex cohabiting couples. We also found evidence of contextual effects: living in a state with a constitutional ban against same-sex marriage was significantly associated with higher levels of instability for same- and different-sex cohabiting couples. The level of stability in both same-sex and different-sex cohabiting couples is not on par with that of different-sex married couples. The findings contribute to a growing literature on health and well-being of same-sex couples and provide a broader understanding of family life.

  12. Interactive Effects of Culture and Sex Hormones on Sex Role Orientation

    Directory of Open Access Journals (Sweden)

    Belinda ePletzer

    2015-07-01

    Full Text Available Sex role orientation, i.e. a person’s masculinity or femininity, influences cognitive and emotional performance, like biological sex. While it is now widely accepted that sex differences are modulated by the hormonal status of female participants (menstrual cycle, hormonal contraceptive use, the question, whether hormonal status and sex hormones also modulate participants sex role orientation has hardly been addressed previously. The present study assessed sex role orientation and hormonal status as well as sex hormone levels in three samples of participants from two different cultures (Northern American, Middle European. Menstrual cycle phase did not affect participant’s masculinity or femininity, but had a significant impact on reference group. While women in their follicular phase (low levels of female sex hormones determined their masculinity and femininity in reference to men, women in their luteal phase (high levels of female sex hormones determined their masculinity and femininity in reference to women. Hormonal contraceptive users rated themselves as significantly more feminine and less masculine than naturally cycling women. Furthermore, the impact of biological sex on the factorial structure of sex role orientation as well as the relationship of estrogen to masculinity/femininity was modulated by culture. We conclude that culture and sex hormones interactively affect sex role orientation and hormonal status of participants should be controlled for when assessing masculinity and/or femininity.

  13. Romance tourism or female sex tourism?

    Science.gov (United States)

    Bauer, Irmgard L

    2014-01-01

    Love, sex and the female traveller: romance tourism or female sex tourism? The phenomenon of women travelling in search of relationships with local men in developing countries has been studied for the last 20 years. However, it appears little known in travel medicine. Relevant literature was found through PubMed, Science Direct, ProQuest and Google Scholar. The reference lists of selected articles identified further sources. Historical records of women travellers to far-away countries abound. Then, as now, women not only searched for the erotic 'other' but made romance and sex the purpose of their trip. Today, increasing numbers of women travel to destinations in developing countries where sex with local men is the main attraction. This pastime raises concerns not only for the women themselves but for the local men involved as well as their sex partners and the local communities. Although more research is necessary, comparing the criteria that describe men travelling for sex and relationships and women travelling for sex and relationships appears to suggest that there is very little difference between the two, regardless of what the pursuit is called. Women looking for sex with local men are sex tourists, too. Recognition of this fact needs to influence the pre and post travel care of female travellers. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Voices of Māori Sex Workers

    OpenAIRE

    Escaravage, Elise

    2016-01-01

    Aotearoa (New Zealand) is the only country in the world to have decriminalized sex work. The Prostitution Reform Act (PRA henceforth) was enacted in 2003 with the aim to safeguard the human rights of sex workers, and create a framework that is conducive to public health. Skeptics of this policy argue that the law reform was targeting indoor workers while the livelihood of street-based sex workers did not see significant improvements (Justice Acts, 2014). It is known that Māori sex workers are...

  15. Update on sexed semen technology in cattle.

    Science.gov (United States)

    Seidel, G E

    2014-05-01

    The technology in current use for sexing sperm represents remarkable feats of engineering. These flow cytometer/cell sorters can make over 30 000 consecutive evaluations of individual sperm each second for each nozzle and sort the sperm into three containers: X-sperm, Y-sperm and unsexable plus dead sperm. Even at these speeds it is not economical to package sperm at standard numbers per inseminate. However, with excellent management, pregnancy rates in cattle with 2 million sexed sperm per insemination dose are about 80% of those with conventional semen at normal sperm doses. This lowered fertility, in part due to damage to sperm during sorting, plus the extra cost of sexed semen limits the applications that are economically feasible. Even so, on the order of 2 million doses of bovine semen are sexed annually in the United States. The main application is for dairy heifers to have heifer calves, either for herd expansion or for sale as replacements, often for eventual export. Breeders of purebred cattle often use sexed semen for specific matings; thawing and then sexing frozen semen and immediately using the few resulting sexed sperm for in vitro fertilization is done with increasing frequency. Beef cattle producers are starting to use sexed semen to produce crossbred female replacements. Proprietary improvements in sperm sexing procedures, implemented in 2013, are claimed to improve fertility between 4 and 6 percentage points, or about 10%.

  16. Unusually dynamic sex roles in a fish.

    Science.gov (United States)

    Forsgren, Elisabet; Amundsen, Trond; Borg, Asa A; Bjelvenmark, Jens

    2004-06-03

    Sex roles are typically thought of as being fixed for a given species. In most animals males compete for females, whereas the females are more reluctant to mate. Therefore sexual selection usually acts most strongly on males. This is explained by males having a higher potential reproductive rate than females, leading to more males being sexually active (a male-biased operational sex ratio). However, what determines sex roles and the strength of sexual selection is a controversial and much debated question. In this large-scale field study, we show a striking temporal plasticity in the mating competition of a fish (two-spotted goby, Gobiusculus flavescens). Over the short breeding season fierce male-male competition and intensive courtship behaviour in males were replaced by female-female competition and actively courting females. Hence, sex role reversal occurred rapidly. This is the first time that a shift in sex roles has been shown in a vertebrate. The shift might be explained by a large decline in male abundance, strongly skewing the sex ratio towards females. Notably, the sex role reversal did not occur at an equal operational sex ratio, contrary to established sex role theory.

  17. Sex Trading Among Hazardously Drinking Jailed Women.

    Science.gov (United States)

    Schonbrun, Yael Chatav; Johnson, Jennifer; Anderson, Bradley J; Stein, Michael D

    For women involved in sex trading, both alcohol problems and passage through the criminal justice system are highly prevalent. This study is the first to conduct a focused examination of factors associated with sex trading among hazardously drinking, pretrial, jailed women. Cocaine use, social support for alcohol abstinence, and more days incarcerated in the 90 days leading up to the index incarceration were significantly associated with sex trading involvement among alcoholic women. Helping incarcerated alcoholic women reduce cocaine use and improve sober support networks during and following an incarceration may minimize sex trading after release.

  18. How Sex Selection Undermines Reproductive Autonomy.

    Science.gov (United States)

    Browne, Tamara Kayali

    2017-06-01

    Non-medical sex selection is premised on the notion that the sexes are not interchangeable. Studies of individuals who undergo sex selection for non-medical reasons, or who have a preference for a son or daughter, show that they assume their child will conform to the stereotypical roles and norms associated with their sex. However, the evidence currently available has not succeeded in showing that the gender traits and inclinations sought are caused by a "male brain" or a "female brain". Therefore, as far as we know, there is no biological reason why parents cannot have the kind of parenting experience they seek with a child of any sex. Yet gender essentialism, a set of unfounded assumptions about the sexes which pervade society and underpin sexism, prevents parents from realising this freedom. In other words, unfounded assumptions about gender constrain not only a child's autonomy, but also the parent's. To date, reproductive autonomy in relation to sex selection has predominantly been regarded merely as the freedom to choose the sex of one's child. This paper points to at least two interpretations of reproductive autonomy and argues that sex selection, by being premised on gender essentialism and/or the social pressure on parents to ensure their children conform to gender norms, undermines reproductive autonomy on both accounts.

  19. Decreasing Human Trafficking through Sex Work Decriminalization.

    Science.gov (United States)

    Albright, Erin; D'Adamo, Kate

    2017-01-01

    In order to decrease human trafficking, health care workers should support the full decriminalization of prostitution. Similar to trafficking in other forms of labor, preventing trafficking in the sex trade requires addressing the different forms of marginalization that create vulnerable communities. By removing punitive laws that prevent reporting of exploitation and abuse, decriminalization allows sex workers to work more safely, thereby reducing marginalization and vulnerability. Decriminalization can also help destigmatize sex work and help resist political, social, and cultural marginalization of sex workers. © 2017 American Medical Association. All Rights Reserved.

  20. Evolutionary stability of sex chromosomes in snakes.

    Science.gov (United States)

    Rovatsos, Michail; Vukić, Jasna; Lymberakis, Petros; Kratochvíl, Lukáš

    2015-12-22

    Amniote vertebrates possess various mechanisms of sex determination, but their variability is not equally distributed. The large evolutionary stability of sex chromosomes in viviparous mammals and birds was believed to be connected with their endothermy. However, some ectotherm lineages seem to be comparably conserved in sex determination, but previously there was a lack of molecular evidence to confirm this. Here, we document a stability of sex chromosomes in advanced snakes based on the testing of Z-specificity of genes using quantitative PCR (qPCR) across 37 snake species (our qPCR technique is suitable for molecular sexing in potentially all advanced snakes). We discovered that at least part of sex chromosomes is homologous across all families of caenophidian snakes (Acrochordidae, Xenodermatidae, Pareatidae, Viperidae, Homalopsidae, Colubridae, Elapidae and Lamprophiidae). The emergence of differentiated sex chromosomes can be dated back to about 60 Ma and preceded the extensive diversification of advanced snakes, the group with more than 3000 species. The Z-specific genes of caenophidian snakes are (pseudo)autosomal in the members of the snake families Pythonidae, Xenopeltidae, Boidae, Erycidae and Sanziniidae, as well as in outgroups with differentiated sex chromosomes such as monitor lizards, iguanas and chameleons. Along with iguanas, advanced snakes are therefore another example of ectothermic amniotes with a long-term stability of sex chromosomes comparable with endotherms. © 2015 The Author(s).

  1. Female Sex Offenders: Public Awareness and Attributions.

    Science.gov (United States)

    Cain, Calli M; Anderson, Amy L

    2016-12-01

    Traditional gender roles, sex scripts, and the way female sex offenders are portrayed in the media may lead to misconceptions about who can commit sexual offenses. Sexual crimes by women may go unnoticed or unreported if there is a general lack of awareness that females commit these crimes. Data from the 2012 Nebraska Annual Social Indicators Survey were used to determine whether the public perceives women as capable sex offenders and the perceived causes of female sex offending. The traditional focus on male sex offenders by researchers, media, and politicians, in addition to gender stereotypes, introduces the possibility of group differences (e.g., between men and women) in perceptions of female sex offenders. Consequently, two secondary analyses were conducted that tested for group differences in both the public's perception of whether females can commit sex offenses and the explanations selected for why females sexually offend. The findings suggest that the public does perceive women as capable sex offenders, although there were group differences in the causal attributions for female sex offending.

  2. Beyond the 'safe sex' propaganda.

    Science.gov (United States)

    Hadzic, Maja; Khajehei, Marjan

    2010-01-01

    In this paper, we discuss sexual relationships among teenagers, the related issues, and suggest addressing the issues through effective education programs for both teenagers and their parents. We also discuss the main issues resulting from initiation of sexual relationship during adolescence such as unwanted pregnancy, maternal mortality, abortion, sexually transmitted diseases and damaged mental health. In addition, we highlight the lack of adequate sex education in teenagers and emphasize on the negative influence of TV programs and the harmful effects of dysfunctional families. Moreover, this article proposes equipping teenagers with knowledge that will help them understand not only physical but also emotional, social, and mental dynamics of sexual relationships. We believe that this approach would intervene much earlier in their life, help teenagers make healthy decision and minimize negative consequences of their personal choices.

  3. Sex and Intimacy after Stroke.

    Science.gov (United States)

    Kautz, Donald D; Van Horn, Elizabeth R

    The sequelae of a stroke can negatively affect sex and intimacy for survivors and their partners. This clinical article offers practical evidence-based recommendations for nurses to use in advising couples who may be experiencing sexual problems due to decreased desire, erectile dysfunction, vaginal dryness, paraparesis, pain, spasticity, fatigue, aphasia, concrete thinking, emotional lability, shame, embarrassment, fear, depression, or neurogenic bladder. Recent research and clinical articles show that intimacy and sexual concerns are often ignored by the rehabilitation team, yet research shows that couples want information to assist them to maintain their sexual relationships. Using the PLISSIT model to address sexual concerns, nurses can facilitate discussions to aid couples toward improved sexual function and quality of life.

  4. Sex Differences in Tibiocalcaneal Kinematics

    Directory of Open Access Journals (Sweden)

    Sinclair Jonathan

    2014-08-01

    Full Text Available Purpose. Female runners typically suffer more from chronic running injuries than age-matched males, although the exact biome-chanical mechanisms behind the increased susceptibility of female runners are unknown. This study aimed to compare sex differences in tibiocalcaneal kinematics during the stance phase of running. Methods. Twenty male and twenty female participants ran at 4.0 m · s–1. Tibiocalcaneal kinematics were measured using an eight-camera motion analysis system and compared using independent samples t tests. Results. Peak eversion and tibial internal rotation angles were shown to be significantly greater in female runners. Conclusions. based on these observations, it was determined that female runners may be at increased risk from chronic injury development in relation to excessive tibiocalcaneal motions in the coronal and transverse planes.

  5. Reinventing Sex: The Construction of Realistic Definitions of Sex and Gender.

    Science.gov (United States)

    Small, Chanley M.

    1998-01-01

    Presents a set of criteria for constructing a fair and realistic understanding of sex. Recognizes the impact that science can have on social policies and values and recommends that the definitions of sex and gender be carefully crafted. (DDR)

  6. Television Sex Roles in the 1980s: Do Viewers' Sex and Sex Role Orientation Change the Picture?

    Science.gov (United States)

    Dambrot, Faye H.; And Others

    1988-01-01

    Investigates the viewer perceptions of female and male television characters as a result of viewer sex and sex role orientation, based on the responses of 677 young adults to the Personal Attributes Questionnaire (PAQ). Viewer gender had an impact on the rating of female characters. (FMW)

  7. BIOLOGICAL SEX, SEX-ROLE ORIENTATION, MASCULINE SEX-ROLE STRESS, DISSIMULATION AND SELF-REPORTED FEARS

    NARCIS (Netherlands)

    ARRINDELL, WA; KOLK, AM; PICKERSGILL, MJ; HAGEMAN, WJJM

    1993-01-01

    Given meta-analytic findings showing females to be generally more fearful than males on multi-dimensional self-report measures of fear, an empirical attempt was made to examine whether this outcome could be explained by psychological factors such as sex role orientation and masculine sex role

  8. Conclusions: Getting real about sex - embedding an embodied sex education in schools

    OpenAIRE

    Alldred, P; David, ME

    2007-01-01

    GET REAL ABOUT SEX: The Politics and Practice of Sex Education explores how cultural ideas about gender, sexuality and parenthood play out in the sex and relationship education classroom. It presents new material from a detailed study and analyses the struggle to raise the status of sex and relationship education against academic and market-driven priorities. It locates the dynamics of the classroom within those of the school and asks: What do the different parties in teaching and learning -...

  9. Correlates of Forced Sex Among Populations of Men Who Have Sex with Men in Thailand

    OpenAIRE

    Guadamuz, Thomas E.; Wimonsate, Wipas; Varangrat, Anchalee; Phanuphak, Praphan; Jommaroeng, Rapeepun; Mock, Philip A.; Tappero, Jordan W.; van Griensven, Frits

    2009-01-01

    Although forced sex is a correlate of HIV infection, its prevalence and associated risks are not well described among men who have sex with men (MSM) in developing-country settings. Between March and October 2005, we assessed the prevalence of forced sex and correlates among populations of MSM (this includes general MSM, male sex workers, and male-to-female transgender persons) in Thailand using a community-based sample. Participants were enrolled from venues around Bangkok, Chiangmai, and Ph...

  10. Molecular sex differences in human serum.

    Directory of Open Access Journals (Sweden)

    Jordan M Ramsey

    Full Text Available Sex is an important factor in the prevalence, incidence, progression, and response to treatment of many medical conditions, including autoimmune and cardiovascular diseases and psychiatric conditions. Identification of molecular differences between typical males and females can provide a valuable basis for exploring conditions differentially affected by sex.Using multiplexed immunoassays, we analyzed 174 serum molecules in 9 independent cohorts of typical individuals, comprising 196 males and 196 females. Sex differences in analyte levels were quantified using a meta-analysis approach and put into biological context using k-means to generate clusters of analytes with distinct biological functions. Natural sex differences were established in these analyte groups and these were applied to illustrate sexually dimorphic analyte expression in a cohort of 22 males and 22 females with Asperger syndrome. Reproducible sex differences were found in the levels of 77 analytes in serum of typical controls, and these comprised clusters of molecules enriched with distinct biological functions. Analytes involved in fatty acid oxidation/hormone regulation, immune cell growth and activation, and cell death were found at higher levels in females, and analytes involved in immune cell chemotaxis and other indistinct functions were higher in males. Comparison of these naturally occurring sex differences against a cohort of people with Asperger syndrome indicated that a cluster of analytes that had functions related to fatty acid oxidation/hormone regulation was associated with sex and the occurrence of this condition.Sex-specific molecular differences were detected in serum of typical controls and these were reproducible across independent cohorts. This study extends current knowledge of sex differences in biological functions involved in metabolism and immune function. Deviations from typical sex differences were found in a cluster of molecules in Asperger syndrome

  11. Conflict over condition-dependent sex allocation can lead to mixed sex-determination systems

    NARCIS (Netherlands)

    Kuijper, Bram; Pen, Ido

    Theory suggests that genetic conflicts drive turnovers between sex-determining mechanisms, yet these studies only apply to cases where sex allocation is independent of environment or condition. Here, we model parent-offspring conflict in the presence of condition-dependent sex allocation, where the

  12. Sex ratio selection and multi-factorial sex determination in the housefly : A dynamic model

    NARCIS (Netherlands)

    Kozielska, M.A.; Pen, I.R.; Beukeboom, L.W.; Weissing, F.J.

    Sex determining (SD) mechanisms are highly variable between different taxonomic groups and appear to change relatively quickly during evolution. Sex ratio selection could be a dominant force causing such changes. We investigate theoretically the effect of sex ratio selection on the dynamics of a

  13. "Dangerous Presumptions": How Single-Sex Schooling Reifies False Notions of Sex, Gender, and Sexuality

    Science.gov (United States)

    Jackson, Janna

    2010-01-01

    Due to the recent changes in federal regulations about gender equity in education in the USA, some policy makers have resurrected single-sex public education. Because single-sex schooling ignores the complexity of sex, gender, and sexuality, it sets up a "separate but equal" system that is anything but. Discounting the ways in which gender is…

  14. Do Sex Differences Define Gender-Related Individual Differences within the Sexes? Evidence from Three Studies.

    Science.gov (United States)

    Lippa, Richard

    1995-01-01

    Studied three different criteria of within-sex, gender-related individual differences taken from three studies. Data showed that items displaying large sex differences tended also to correlate most strongly with independent gender-related criteria within the sexes. Discusses assessment implications for gender-related and other group-related…

  15. Prenatal sex hormone effects on child and adult sex-typed behavior: methods and findings

    NARCIS (Netherlands)

    van de Beek, C.; Cohen-Bendahan, C.; Berenbaum, S.

    2005-01-01

    There is now good evidence that human sex-typed behavior is influenced by sex hormones that are present during prenatal development, confirming studies in other mammalian species. Most of the evidence comes from clinical populations, in which prenatal hormone exposure is atypical for a person's sex,

  16. Conflict over condition-dependent sex allocation can lead to mixed sex-determination systems

    NARCIS (Netherlands)

    Kuijper, Bram; Pen, Ido

    2014-01-01

    Theory suggests that genetic conflicts drive turnovers between sex-determining mechanisms, yet these studies only apply to cases where sex allocation is independent of environment or condition. Here, we model parent-offspring conflict in the presence of condition-dependent sex allocation, where the

  17. Development of Gender Discrimination: Effect of Sex-Typical and Sex-Atypical Toys.

    Science.gov (United States)

    Etaugh, Claire; Duits, Terri L.

    Toddlers (41 girls and 35 boys) between 18 and 37 months of age were given four gender discrimination tasks each consisting of 6 pairs of color drawings. Three of the tasks employed color drawings of preschool girls and boys holding either a sex-typical toy, a sex-atypical toy, or no toy. The fourth employed pictures of sex-typical masculine and…

  18. Alcohol and Sex Offending: What Do Child Sex Offenders Think about Drinking?

    Science.gov (United States)

    Monson, Candice M.; Jones, Lisa M.; Rivers, P. Clayton; Blum, Steven B.

    1998-01-01

    Examines relationships between general and sex-specific alcohol expectancies and drinking before offending with child sex offenders. Results show that sex-specific expectancies were the best predictor of the proportion of times the offenders reported drinking before offending. Highlights the importance of assessing expectancies related to…

  19. Do sex differences in rumination explain sex differences in depression?

    Science.gov (United States)

    Shors, Tracey J; Millon, Emma M; Chang, Han Yan M; Olson, Ryan L; Alderman, Brandon L

    2017-01-02

    It is generally accepted that women tend to ruminate more than men do and these thought patterns are often associated with depressive symptoms (Nolen-Hoeksema et al., ). Based on these findings, we considered whether the relationship between rumination and depression is stronger in women than in men and if so, whether this might explain the higher prevalence of major depressive disorder (MDD) in women and finally, whether the association can be disrupted through a mind/body intervention. Adult men and women, most of whom were clinically depressed, participated in an intervention known as MAP Training, which combines "mental" training with silent meditation and "physical" training with aerobic exercise (Shors et al., ). After eight weeks of training, both men and women reported significantly fewer symptoms of depression and fewer ruminative thoughts (Alderman et al., ). Statistical correlations between depressive symptoms and ruminative thoughts were strong and significant (rho > 0.50; p depressive symptoms relate to "reflective" ruminations, which involve analyses of past events, feelings, and behaviors. This is also the only relationship that dissipated after the intervention. In general, these analyses suggest that the strength of the relationship between depressive symptoms and rumination does not necessarily explain sex differences in depression; but because the relationship is strong, targeting rumination through intervention can reduce the incidence of MDD, which is more prevalent among women. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  20. Dilemma and quantum battle of sexes

    International Nuclear Information System (INIS)

    Nawaz, Ahmad; Toor, A H

    2004-01-01

    We analysed quantum version of the game battle of sexes using a general initial quantum state. For a particular choice of initial entangled quantum state it is shown that the classical dilemma of the battle of sexes can be resolved and a unique solution of the game can be obtained

  1. Sex reduces genetic variation: a multidisciplinary review.

    Science.gov (United States)

    Gorelick, Root; Heng, Henry H Q

    2011-04-01

    For over a century, the paradigm has been that sex invariably increases genetic variation, despite many renowned biologists asserting that sex decreases most genetic variation. Sex is usually perceived as the source of additive genetic variance that drives eukaryotic evolution vis-à-vis adaptation and Fisher's fundamental theorem. However, evidence for sex decreasing genetic variation appears in ecology, paleontology, population genetics, and cancer biology. The common thread among many of these disciplines is that sex acts like a coarse filter, weeding out major changes, such as chromosomal rearrangements (that are almost always deleterious), but letting minor variation, such as changes at the nucleotide or gene level (that are often neutral), flow through the sexual sieve. Sex acts as a constraint on genomic and epigenetic variation, thereby limiting adaptive evolution. The diverse reasons for sex reducing genetic variation (especially at the genome level) and slowing down evolution may provide a sufficient benefit to offset the famed costs of sex. © 2010 The Author(s). Evolution© 2010 The Society for the Study of Evolution.

  2. Sex selection: the systematic elimination of girls.

    Science.gov (United States)

    Oomman, Nandini; Ganatra, Bela R

    2002-05-01

    In strongly patriarchal societies, where the cultural and economic value of sons is at a premium, son preference manifests itself in many ways, ranging from differential allocation of household resources, medical care and neglect of girl children to female infanticide. With the increasing availability of ultrasound in the mid-1980s sex determination followed by sex-selective abortion began to become widespread as well. The following paper introduces this Roundtable and discusses the following questions: Is sex selection a part of women's right to free choice and control over their reproduction? What is the role of the medical profession? Are all manifestations of sex selection equally unethical? Are there solutions? Do the solutions themselves pose new ethical dilemmas? Following this paper, four respondents put different points of view on sex selection as a gender-based preference for a pregnancy; progress in getting the Supreme Court of India to implement a 1994 law regulating the use of antenatal diagnostic technology; why sex selection should be available as a form of reproductive choice; and why sex selection may be empowering for women and justify their actions in the short run, given the demands on them. All agree that only improved status for women and girls will reduce the demand for sex selection.

  3. Toward a Redefinition of Sex and Gender.

    Science.gov (United States)

    Unger, Rhoda Kesler

    1979-01-01

    Present psychological terminology facilitates biologically determinist models of sex differences, making it less likely that environmental sources of such differences will be explored. The term "gender," rather than "sex," should be used for those characteristics socioculturally considered appropriate to males and females.…

  4. Sex Differences in Cardiovascular Drug Response

    NARCIS (Netherlands)

    E.M. Rodenburg (Eline)

    2012-01-01

    textabstractIn the early sixties, a prominent professor in Clinical Pharmacology at the University College in London, D.R. Laurence, stated: “There are no clinically important sex differences in drug action, except, of course, to sex steroid hormones, but the subject is poorly documented. Women

  5. Sex Differences in the Experience of Widowhood.

    Science.gov (United States)

    Barrett, Carol J.

    Previous writers have presumed that widowhood is more stressful for one sex or the other. Hypotheses derived from demographic considerations and sex role developmental theory compared the needs and resources of 147 widows and 42 widowers, relative to 190 married persons. All subjects were non-institutionalized urban residents aged 62 or over. The…

  6. Number of Single-Sex Schools Growing

    Science.gov (United States)

    Barak, Tal

    2004-01-01

    The U.S. Department of Education's office for civil rights has proposed amending the regulations governing Title IX of the Education Amendments of 1972--which prohibits sex discrimination in programs that receive federal money--to allow more flexibility in offering single-sex schools or classes. This article discusses the rapid growth of…

  7. Sex Differences and Depression in Puerto Rico.

    Science.gov (United States)

    Canino, Glorisa J.; And Others

    1987-01-01

    Examined sex differences in rates of depressive disorders and depressive symptomatology, as measured by the Diagnostic Interview Schedule, for an island-wide probability sample of Puerto Rico. Found depression significantly more prevalent among women than men. Discusses risk factors from a sex-role and cultural perspective. (Author/KS)

  8. Social Conflict and Sex Equity in Education.

    Science.gov (United States)

    Quantz, Richard A.

    1983-01-01

    Holds that male/female differences in such behavior characteristics as aggression, cooperation/competition, compliance, and anxiety are not innate, but rather are social strategies available to both sexes and utilized whenever reasonable. Suggests that the sex equity problems in education can be solved by eliminating differential treatment of boys…

  9. Microbial manipulation of host sex determination

    NARCIS (Netherlands)

    Beukeboom, Leo W.

    A recent study in the lepidopteran Ostrinia scapulalis shows that endosymbionts can actively manipulate the sex determination mechanism of their host. Wolbachia bacteria alter the sex-specific splicing of the doublesex master switch gene. In ZZ males of this female heterogametic system, the female

  10. Lineage Selection and the Maintenance of Sex

    Science.gov (United States)

    de Vienne, Damien M.; Giraud, Tatiana; Gouyon, Pierre-Henri

    2013-01-01

    Sex predominates in eukaryotes, despite its short-term disadvantage when compared to asexuality. Myriad models have suggested that short-term advantages of sex may be sufficient to counterbalance its twofold costs. However, despite decades of experimental work seeking such evidence, no evolutionary mechanism has yet achieved broad recognition as explanation for the maintenance of sex. We explore here, through lineage-selection models, the conditions favouring the maintenance of sex. In the first model, we allowed the rate of transition to asexuality to evolve, to determine whether lineage selection favoured species with the strongest constraints preventing the loss of sex. In the second model, we simulated more explicitly the mechanisms underlying the higher extinction rates of asexual lineages than of their sexual counterparts. We linked extinction rates to the ecological and/or genetic features of lineages, thereby providing a formalisation of the only figure included in Darwin's “The origin of species”. Our results reinforce the view that the long-term advantages of sex and lineage selection may provide the most satisfactory explanations for the maintenance of sex in eukaryotes, which is still poorly recognized, and provide figures and a simulation website for training and educational purposes. Short-term benefits may play a role, but it is also essential to take into account the selection of lineages for a thorough understanding of the maintenance of sex. PMID:23825582

  11. Oral sex, oral health and orogenital infections

    Directory of Open Access Journals (Sweden)

    Rajiv Saini

    2010-01-01

    Full Text Available Oral sex is commonly practiced by sexually active male-female and same-gender couples of various ages, including adolescents. The various type of oral sex practices are fellatio, cunnilingus and analingus. Oral sex is infrequently examined in research on adolescents; oral sex can transmit oral, respiratory, and genital pathogens. Oral health has a direct impact on the transmission of infection; a cut in your mouth, bleeding gums, lip sores or broken skin increases chances of infection. Although oral sex is considered a low risk activity, it is important to use protection and safer sex precautions. There are various methods of preventing infection during oral sex such as physical barriers, health and medical issues, ethical issues and oral hygiene and dental issues. The lesions or unhealthy periodontal status of oral cavity accelerates the phenomenon of transmission of infections into the circulation. Thus consequences of unhealthy or painful oral cavity are significant and oral health should be given paramount importance for the practice of oral sex.

  12. Children in Same-Sex Marriages

    Science.gov (United States)

    Solodnikov, V. V.; Chkanikova, A. M.

    2009-01-01

    In Russia, sociologists do not have reliable statistical data as to the number of same-sex unions and the number of children being brought up in these families, and non-Russian studies on the topic are flawed and misleading. Russians are said to be antagonistic to the idea of children being raised in same-sex households. People are concerned over…

  13. Conflicting Philosophies of School Sex Education.

    Science.gov (United States)

    Reiss, Michael J.

    1995-01-01

    Explores the strengths and weaknesses of the five main philosophical positions currently found in school sex education. Argues that valid sex education promotes rational sexual autonomy, requires pupils to consider the needs and wishes of others, and occurs within a moral framework. Suggests teachers adopt a supportive but neutral position. (MJP)

  14. Participation in Sex Work: Students' Views

    Science.gov (United States)

    Roberts, Ron; Sanders, Teela; Myers, Ellie; Smith, Debbie

    2010-01-01

    Increasing evidence points to student involvement in the sex industry. The current study comprised a cross-sectional sample of 315 undergraduates at a London university. Using a semi-structured questionnaire, data were gathered on students' financial and employment circumstances and their views on participation in sex work. Results suggested…

  15. Inherent Dangers in Orogenital Sex During Pregnancy

    African Journals Online (AJOL)

    Coitus and cunnilingus during pregnancy are generally safe; whereas orogenital sex involving vaginal air insufflations can be very dangerous, causing even the death of the women. We carried out a search of case reports and reviews concerning air embolism during pregnancy due to orogenital sex. Physicians ...

  16. What's Missing? Anti-Racist Sex Education!

    Science.gov (United States)

    Whitten, Amanda; Sethna, Christabelle

    2014-01-01

    Contemporary sexual health curricula in Canada include information about sexual diversity and queer identities, but what remains missing is any explicit discussion of anti-racist sex education. Although there exists federal and provincial support for multiculturalism and anti-racism in schools, contemporary Canadian sex education omits crucial…

  17. Can Sex Education Delay Early Sexual Debut?

    Science.gov (United States)

    Erkut, Sumru; Grossman, Jennifer M.; Frye, Alice A.; Ceder, Ineke; Charmaraman, Linda; Tracy, Allison J.

    2013-01-01

    In this study, we examine whether a nine-lesson sex education intervention, "Get Real: Comprehensive Sex Education That Works," implemented in sixth grade, can reduce the number of adolescents who might otherwise become "early starters" of sexual activity (defined as heterosexual intercourse) by seventh grade. Participants were…

  18. The Gestalt Experiment in Sex Therapy.

    Science.gov (United States)

    Mosher, Donald L.

    1979-01-01

    The Gestalt experiment is applicable to sex therapy. Familiarity with modes and methods of experimenting permits the therapist's creativity to emerge. Applications of sexual metaphors and sex dysfunction as a nightmare are presented, using methods drawn from Gestalt dream work. The use of Gestalt experiments are illustrated in a client-therapist…

  19. Dangerous Liaisons: Substance Abuse and Sex.

    Science.gov (United States)

    Columbia Univ., New York, NY. National Center on Addiction and Substance Abuse.

    This report takes a comprehensive look at the connections between alcohol, drug use, and sex. Two national data sets on more than 34,000 teenagers and two sets on arrested and incarcerated sex offenders were analyzed. A review of the literature, interviews with experts, and an examination of programs aimed at prevention of abuse were included in…

  20. Sex Role Stereotypes Are Alive and Well.

    Science.gov (United States)

    Snodgrass, Sara E.

    Two studies, in late 1988 and early 1990, examined sex-role stereotypes held by northeastern liberal arts college students (N=719) and southern state university college students (N=145). The first study used the Personal Attributes Questionnaire (PAQ) and compared ratings of men and women with the traditional sex-roles represented by the PAQ in…

  1. Occupational Segregation by Sex: Determinants and Changes.

    Science.gov (United States)

    Beller, Andrea H.

    1982-01-01

    This study found that occupational sex segregation began to diminish during the 1970s, in conjunction with enforcement of the equal employment opportunity laws against sex discrimination in employment. The success of these laws suggests that discrimination was originally a determinant of occupational segregation. (Author/SK)

  2. The variability is in the sex chromosomes.

    Science.gov (United States)

    Reinhold, Klaus; Engqvist, Leif

    2013-12-01

    Sex differences in the mean trait expression are well documented, not only for traits that are directly associated with reproduction. Less is known about how the variability of traits differs between males and females. In species with sex chromosomes and dosage compensation, the heterogametic sex is expected to show larger trait variability ("sex-chromosome hypothesis"), yet this central prediction, based on fundamental genetic principles, has never been evaluated in detail. Here we show that in species with heterogametic males, male variability in body size is significantly larger than in females, whereas the opposite can be shown for species with heterogametic females. These results support the prediction of the sex-chromosome hypothesis that individuals of the heterogametic sex should be more variable. We argue that the pattern demonstrated here for sex-specific body size variability is likely to apply to any trait and needs to be considered when testing predictions about sex-specific variability and sexual selection. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  3. Questions and Answers about Sex (For Parents)

    Science.gov (United States)

    ... español Preguntas y respuestas sobre sexo Answering their kids' questions about sex is a responsibility that many parents dread. Otherwise ... avoided. Parents can help foster healthy feelings about sex if they answer kids' questions in an age-appropriate way. When do ...

  4. Curious Sex Ratios and Cytoplasmic Genes

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 6. Curious Sex Ratios and Cytoplasmic Genes Microbes Can Distort the Sex Ratio of Populations. Stephen J Freeland Laurence D Hurst. General Article Volume 2 Issue 6 June 1997 pp 68-78 ...

  5. Sex Parties: Female Teen Sexual Experimentation

    Science.gov (United States)

    Toscano, Sharyl Eve

    2006-01-01

    Adolescent participants in a study aimed at exploring the nature and characteristics of girls' dating relationships revealed the phenomenon of sex parties. These teens defined a "sex party" as an opportunity to engage in sexual contact outside of typical dating relationships. Sexual activity could involve actual intercourse, but usually involved…

  6. Sex Roles among Married and Unmarried Couples.

    Science.gov (United States)

    Kotkin, Mark

    1983-01-01

    An investigation of sex roles among married and cohabitating couples showed: (1) that male career success, male career precedence, the decision to marry, and conventional allocation of household tasks are all concomitant and (2) that marriage crystallizes sex roles and behaviorally solidifies male career precedence, facilitating the husband's…

  7. Sex Trait Stereotypes in Malaysian Children.

    Science.gov (United States)

    Ward, Colleen

    1985-01-01

    To examine the development of sex-role stereotyping in Malaysia, 80 children were tested with the Sex Stereotype Measurement II. Results revealed that stereotyping increases with age, that the male stereotype is more easily recognized than the female, and that boys are more familiar with the male stereotype than are girls. (KH)

  8. Sex Differences in the Adolescent Brain

    Science.gov (United States)

    Lenroot, Rhoshel K.; Giedd, Jay N.

    2010-01-01

    Adolescence is a time of increased divergence between males and females in physical characteristics, behavior, and risk for psychopathology. Here we will review data regarding sex differences in brain structure and function during this period of the lifespan. The most consistent sex difference in brain morphometry is the 9-12% larger brain size…

  9. Teaching Sex Education to Multiply Handicapped Adolescents.

    Science.gov (United States)

    Smigielski, Patricia A.; Steinmann, Mary J.

    1981-01-01

    A sex education program for an adolescent who is mentally retarded or blind must emphasize concrete teaching, visual compensators, resource persons, repetition of content, and opportunities for social learning. Nurses and special educators can serve as consultants to health educators in planning a sex education program. (JN)

  10. Licensed Practical Nurses' Sex Role Stereotypes.

    Science.gov (United States)

    Wallston, Barbara Strudler; And Others

    1983-01-01

    Examined whether sex-role stereotypes would affect nurses' (N=32) attitudes toward simulations of male and female patients. Emotional style and patients' diagnosis were manipulated. Results showed significant sex-role differences and stereotypical attitudes. Male patients were rated more positively, and were more likely to possess traditional male…

  11. Why Do Sex Chromosomes Stop Recombining?

    Science.gov (United States)

    Ponnikas, Suvi; Sigeman, Hanna; Abbott, Jessica K; Hansson, Bengt

    2018-04-28

    It is commonly assumed that sex chromosomes evolve recombination suppression because selection favours linkage between sex-determining and sexually antagonistic genes. However, although the role of sexual antagonism during sex chromosome evolution has attained strong support from theory, experimental and observational evidence is rare or equivocal. Here, we highlight alternative, often neglected, hypotheses for recombination suppression on sex chromosomes, which invoke meiotic drive, heterozygote advantage, and genetic drift, respectively. We contrast the hypotheses, the situations when they are likely to be of importance, and outline why it is surprisingly difficult to test them. Lastly, we discuss future research directions (including modelling, population genomics, comparative approaches, and experiments) to disentangle the different hypotheses of sex chromosome evolution. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Perceived control and communication about sex: A study of South ...

    African Journals Online (AJOL)

    Caregiver–youth communication about sex protects youth against HIV/AIDS, and caregivers who believe that sex knowledge is important are more likely to talk to their youth about sex. However, caregivers who experience barriers to communication about sex may not talk to their youth about sex even if the caregiver ...

  13. The accuracy of 2D ultrasound prenatal sex determination ...

    African Journals Online (AJOL)

    Most of the women were happy even when the sex differed from that which they desired. Conclusion: Prenatal sonographic sex determination has a high sensitivity index. Consequently we advocate its use prior to more invasive sex tests. Keywords: Accuracy, gender determination, prenatal gender, prenatal sex, sex ...

  14. Need for Studies of Sex Discrimination in Public Schools.

    Science.gov (United States)

    1972

    This paper was designed to aid organizations seeking to eliminate sex discrimination in the public schools. Major emphasis was placed on the need for studies of sex discrimination. Six areas of investigation should include: 1) one sex schools; 2) one sex or practically one sex courses in co-ed schools; 3) physical education, sports and other extra…

  15. Resources for Achieving Sex Equity: An Annotated Bibliography.

    Science.gov (United States)

    Miller, Susan W., Comp.

    This annotated bibliography provides a list of resources dealing with sex equity in vocational education. The bibliography first provides operational definitions of "sexism,""sex fair,""sex affirmative,""sex bias," and "affirmative action." It then lists resources under the following topics and/or bibliographic forms: (1) sex role definition, (2)…

  16. How sex work becomes an option: Experiences of female sex workers in Kerman, Iran.

    Science.gov (United States)

    Karamouzian, Mohammad; Foroozanfar, Zohre; Ahmadi, Azal; Haghdoost, Ali Akbar; Vogel, Joanna; Zolala, Farzaneh

    2016-01-01

    Sex work is rarely an occupation of choice for Iranian women and is often described as a last resort. While several factors play a role in creating an environment where individuals become involved in sex work, female sex workers' experiences regarding entry into sex work in Iran are poorly understood. In this qualitative study, a convenience sample of 24 participants was recruited from a drop-in centre for vulnerable women in Kerman, Iran. Through in-depth interviews, participants were asked about their personal lived experiences of initiating sex work. Grounded theory was used to analyse findings from this research. We learned that major factors impacting on women's initiation into sex work circulated around their vulnerability and chronic poverty. Participants continued to sell sex due to their limited opportunities, drug dependence and financial needs. Improving sex workers' economic status could be a vital intervention in providing vulnerable women with options other than sex work. Female sex workers should be provided with government support and educational programmes delivered through special centres. Despite the illegal status of their work, sex workers' needs should be recognised across all aspects of policy and legislation.

  17. Why we should consider sex (and study sex differences) in addiction research.

    Science.gov (United States)

    Sanchis-Segura, Carla; Becker, Jill B

    2016-09-01

    Among mammals, every cell has a biological sex, and the sex of an individual pervades its body and brain. In this review, we describe the processes through which mammals become phenotypically male or female by organizational and activational influences of genes and hormones throughout development. We emphasized that the molecular and cellular changes triggered by sex chromosomes and steroid hormones may generate sex differences in overt physiological functions and behavior, but they may alternatively promote end-point convergences between males and females. Clinical and pre-clinical evidences suggest that sex and gender differences modulate drug consumption as well as of the transition towards drug-promoted pathological states such as dependence and addiction. Additionally, sex differences in drug pharmacokinetics and pharmacodynamics will also influence dependence and addiction as well as side effects of drugs. These effects will further interact with socially gendered factors to result in sex differences in the access to, engagement in and efficacy of any therapeutic attempt. Finally, we maintain that 'sex sameness' is as important as 'sex differences' when building a complete understanding of biology for both males and females and provide a framework with which to classify and guide investigation into the mechanisms mediating sex differences and sex sameness. © 2016 Society for the Study of Addiction.

  18. Sex steroids and glucose metabolism

    Directory of Open Access Journals (Sweden)

    Carolyn A Allan

    2014-04-01

    Full Text Available Testosterone levels are lower in men with metabolic syndrome and type 2 diabetes mellitus (T2DM and also predict the onset of these adverse metabolic states. Body composition (body mass index, waist circumference is an important mediator of this relationship. Sex hormone binding globulin is also inversely associated with insulin resistance and T2DM but the data regarding estrogen are inconsistent. Clinical models of androgen deficiency including Klinefelter's syndrome and androgen deprivation therapy in the treatment of advanced prostate cancer confirm the association between androgens and glucose status. Experimental manipulation of the insulin/glucose milieu and suppression of endogenous testicular function suggests the relationship between androgens and insulin sensitivity is bidirectional. Androgen therapy in men without diabetes is not able to differentiate the effect on insulin resistance from that on fat mass, in particular visceral adiposity. Similarly, several small clinical studies have examined the efficacy of exogenous testosterone in men with T2DM, however, the role of androgens, independent of body composition, in modifying insulin resistance is uncertain.

  19. [Neuroendocrine effect of sex hormones].

    Science.gov (United States)

    Babichev, V N

    2005-01-01

    The paper provides a generalization of data and the results of own experiments on influence ovarian steroids on the hypothalamus and other brain areas related to reproduction. Ovarian hormones have widespread effects throughout the brain: on catecholaminergic neurons and serotonergic pathways and the basal forebrain cholinergic system, as well as the hipocampus, spinal cord, nigrostriatal and mesolimbic system, in addition to glial cells and blood-brain barrier. The widespread influences of these various neuronal systems ovarian steroids have measurable effects on mood and affect as well as on cognition, with implications for dementia. There are developmentally programmed sex differenced in hippocampal structure that may help to explain differences in the strategies which male and female rats use to solve spatial navigation problems. The multiple sites and mechanisms of estrogen action in brain underlie a variety of importants effects on cognitive and other brain functions--coordination of movement, pain, affective state, as well as possible protection in Alzheimer's disease. Estrogen withdrawal after natural or surgical menopause can lead to a host of changes in brain function and behavior.

  20. Novel sex cells and evidence for sex pheromones in diatoms.

    Science.gov (United States)

    Sato, Shinya; Beakes, Gordon; Idei, Masahiko; Nagumo, Tamotsu; Mann, David G

    2011-01-01

    Diatoms belong to the stramenopiles, one of the largest groups of eukaryotes, which are primarily characterized by a presence of an anterior flagellum with tubular mastigonemes and usually a second, smooth flagellum. Based on cell wall morphology, diatoms have historically been divided into centrics and pennates, of which only the former have flagella and only on the sperm. Molecular phylogenies show the pennates to have evolved from among the centrics. However, the timing of flagellum loss--whether before the evolution of the pennate lineage or after--is unknown, because sexual reproduction has been so little studied in the 'araphid' basal pennate lineages, to which Pseudostaurosira belongs. Sexual reproduction of an araphid pennate, Pseudostaurosira trainorii, was studied with light microscopy (including time lapse observations and immunofluorescence staining observed under confocal scanning laser microscopy) and SEM. We show that the species produces motile male gametes. Motility is mostly associated with the extrusion and retrieval of microtubule-based 'threads', which are structures hitherto unknown in stramenopiles, their number varying from one to three per cell. We also report experimental evidence for sex pheromones that reciprocally stimulate sexualization of compatible clones and orientate motility of the male gametes after an initial 'random walk'. The threads superficially resemble flagella, in that both are produced by male gametes and contain microtubules. However, one striking difference is that threads cannot beat or undulate and have no motility of their own, and they do not bear mastigonemes. Threads are sticky and catch and draw objects, including eggs. The motility conferred by the threads is probably crucial for sexual reproduction of P. trainorii, because this diatom is non-motile in its vegetative stage but obligately outbreeding. Our pheromone experiments are the first studies in which gametogenesis has been induced in diatoms by cell

  1. Novel sex cells and evidence for sex pheromones in diatoms.

    Directory of Open Access Journals (Sweden)

    Shinya Sato

    Full Text Available BACKGROUND: Diatoms belong to the stramenopiles, one of the largest groups of eukaryotes, which are primarily characterized by a presence of an anterior flagellum with tubular mastigonemes and usually a second, smooth flagellum. Based on cell wall morphology, diatoms have historically been divided into centrics and pennates, of which only the former have flagella and only on the sperm. Molecular phylogenies show the pennates to have evolved from among the centrics. However, the timing of flagellum loss--whether before the evolution of the pennate lineage or after--is unknown, because sexual reproduction has been so little studied in the 'araphid' basal pennate lineages, to which Pseudostaurosira belongs. METHODS/PRINCIPAL FINDING: Sexual reproduction of an araphid pennate, Pseudostaurosira trainorii, was studied with light microscopy (including time lapse observations and immunofluorescence staining observed under confocal scanning laser microscopy and SEM. We show that the species produces motile male gametes. Motility is mostly associated with the extrusion and retrieval of microtubule-based 'threads', which are structures hitherto unknown in stramenopiles, their number varying from one to three per cell. We also report experimental evidence for sex pheromones that reciprocally stimulate sexualization of compatible clones and orientate motility of the male gametes after an initial 'random walk'. CONCLUSIONS/SIGNIFICANCE: The threads superficially resemble flagella, in that both are produced by male gametes and contain microtubules. However, one striking difference is that threads cannot beat or undulate and have no motility of their own, and they do not bear mastigonemes. Threads are sticky and catch and draw objects, including eggs. The motility conferred by the threads is probably crucial for sexual reproduction of P. trainorii, because this diatom is non-motile in its vegetative stage but obligately outbreeding. Our pheromone experiments

  2. Demographic origins of skewed operational and adult sex ratios: perturbation analyses of two-sex models.

    Science.gov (United States)

    Veran, Sophie; Beissinger, Steven R

    2009-02-01

    Skewed sex ratios - operational (OSR) and Adult (ASR) - arise from sexual differences in reproductive behaviours and adult survival rates due to the cost of reproduction. However, skewed sex-ratio at birth, sex-biased dispersal and immigration, and sexual differences in juvenile mortality may also contribute. We present a framework to decompose the roles of demographic traits on sex ratios using perturbation analyses of two-sex matrix population models. Metrics of sensitivity are derived from analyses of sensitivity, elasticity, life-table response experiments and life stage simulation analyses, and applied to the stable stage distribution instead of lambda. We use these approaches to examine causes of male-biased sex ratios in two populations of green-rumped parrotlets (Forpus passerinus) in Venezuela. Female local juvenile survival contributed the most to the unbalanced OSR and ASR due to a female-biased dispersal rate, suggesting sexual differences in philopatry can influence sex ratios more strongly than the cost of reproduction.

  3. Perceptions of sources of sex education and targets of sex communication: sociodemographic and cohort effects.

    Science.gov (United States)

    Sprecher, Susan; Harris, Gardenia; Meyers, Adena

    2008-01-01

    As part of a larger survey study on young adult sexuality conducted over a 17-year period at a Midwest U.S. university, more than 6,000 college students completed questions on the sources of their sex education and the degree to which they have communicated about sex with various types of individuals. Participants reported receiving more sex education from peers and media than from parents (and mothers more than fathers). Respondents also reported communicating more about sex with peers than with parents or any other categories of individuals. Differences were found in the degree of sex education from various sources and in communication with various targets based on gender, ethnic background, and social class. Furthermore, changes were found over the 17-year period. More recent cohorts of students perceived that they received more sex education from media, peers, and professionals, and communicated more about sex with professionals, relative to earlier cohorts.

  4. Exploring dynamics of anal sex among female sex workers in Andhra Pradesh.

    Science.gov (United States)

    Tucker, Saroj; Krishna, Rama; Prabhakar, Parimi; Panyam, Swarup; Anand, Pankaj

    2012-01-01

    The anal sex among heterosexual couples is on the rise as reported in many scientific studies. Considering that unprotected anal sex has higher risk of human immunodeficiency virus (HIV) transmission than the vaginal sex, we undertook a study to understand the anal sex practices among Female Sex Workers (FSW). The study was conducted among FSW attending 11 randomly selected sexually transmitted infection (STI) clinics in Bill and Melinda Gates supported targeted interventions in Andhra Pradesh. A structured questionnaire was administered to the 555 FSW attending these clinics by project clinic counselors. Informed consent was obtained from all the study participants. Engaging in anal sex was self reported by 22% of sex workers, though demand from clients was reported to be much higher (40%). The reasons for anal sex practices included more money (61%), clout/influence of the client (45%), risk of losing client (27%), and forced sex (1.2%). Factors associated with anal sex were higher number of clients, higher duration of sex work, higher income, and older age group. Associated risks perceived by FSW were bleeding and injury to anal canal (98%) while only 28% associated it with higher HIV transmission risk. Reported Condom and lubricant use was about 88% and 39% respectively. The study shows that there is frequent anal sex, inconsistent condom and infrequent lubricant usage, economic and physical coercion, and low awareness of STI/HIV transmission risk among FSW, which have serious implications for HIV prevention programmes. There is a need to focus on anal sex education and use of lubricants along with condoms during anal sex in FSW-targeted interventions in AP.

  5. More than a Tad: spatiotemporal control of Caulobacter pili.

    Science.gov (United States)

    Mignolet, Johann; Panis, Gaël; Viollier, Patrick H

    2018-04-01

    The Type IV pilus (T4P) is a powerful and sophisticated bacterial nanomachine involved in numerous cellular processes, including adhesion, DNA uptake and motility. Aside from the well-described subtype T4aP of the Gram-negative genera, including Myxococcus, Pseudomonas and Neisseria, the Tad (tight adherence) pilus secretion system re-shuffles homologous parts from other secretion systems along with uncharacterized components into a new type of protein translocation apparatus. A representative of the Tad apparatus, the Caulobacter crescentus pilus assembly (Cpa) machine is built exclusively at the newborn cell pole once per cell cycle. Recent comprehensive genetic analyses unearthed a myriad of spatiotemporal determinants acting on the Tad/Cpa system, many of which are conserved in other α-proteobacteria, including obligate intracellular pathogens and symbionts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Adhesive Pili in UTI Pathogenesis and Drug Development.

    Science.gov (United States)

    Spaulding, Caitlin N; Hultgren, Scott J

    2016-03-15

    Urinary tract infections (UTIs) are one of the most common bacterial infections, affecting 150 million people each year worldwide. High recurrence rates and increasing antimicrobial resistance among uropathogens are making it imperative to develop alternative strategies for the treatment and prevention of this common infection. In this Review, we discuss how understanding the: (i) molecular and biophysical basis of host-pathogen interactions; (ii) consequences of the molecular cross-talk at the host pathogen interface in terms of disease progression; and (iii) pathophysiology of UTIs is leading to efforts to translate this knowledge into novel therapeutics to treat and prevent these infections.

  7. The evolution of female sex pheromones

    Directory of Open Access Journals (Sweden)

    Ally R. HARARI, Hadass STEINITZ

    2013-08-01

    Full Text Available The role of female sex pheromones in natural selection, particularly as a means for species recognition to avoid the generation of hybrid offspring with low fitness, has been widely explored and is generally accepted by scholars. However, the significance of sex pheromones in shaping mate choice (sexual selection and in competition over breeding resources (social selection has been largely ignored. The effect of sexual selection on sex pheromones as a sexually dimorphic signaling trait has been discounted because the amount of pheromone released by females is typically minute, while the role of sex pheromones in competition over breeding resources (other than mates has not yet been considered. As a result of natural selection, variation in sex pheromones among females is expected to be low, and males are not expected to choose their mates among pheromone-releasing conspecific females. Sexual selection, on the other hand, should drive the increase in pheromone variance among females, and males are expected to choose females based on this variation. Moreover, social selection resulting from more general social interactions, for example competition among females for breeding sites and food, should also promote variance among female sex pheromones. Here, we review the current evidence for each of the three selection processes acting on sex pheromones of female moths as an advertising trait. We suggest that the three selection types are not mutually exclusive but rather act together to promote different fitness components in diverse ecological situations [Current Zoology 59 (4: 569–578, 2013].

  8. Putting sex education in its place.

    Science.gov (United States)

    Cassell, C

    1981-04-01

    In order to help reduce fears and anxieties regarding the influence of sex education in a public school setting, school and community sexuality educators need to better articulate the difference between formal and structured sex education and non-formal, informal and incidental sex learning. Sex education is only 1 aspect of the sexual learning process. 2 main points have to be clarified for parents and the general public to set the stage for a new way to view the school and community involvement in the sexual learning process: the schools' sexuality education courses constitute only a small portion of the sexual learning process; and sexual learning is not an event for youth only, but a process spanning life. Sex education (the process) connotates an academic setting with a specific curricula taught by a trained instructor, but sexual learning relates to environmental, non-formal incidental learning from a multitude of sources. Studies indicate that teenagers receive about 90% of their contraceptive and sexuality informaation from peers and mass media and that these sources of information are becoming their preferred sources of sex education. What is needed is a way to address and improve the conditions of sexual learning in the community. As home is the ideal environment for primary and positive sexual learning, parents need support in their role as sex educators. Classroom sexuality education curricula in all school settings have a solid place in the process of sexual learning.

  9. Sexual Murderers: Sex Offender, Murderer, or Both?

    Science.gov (United States)

    Beauregard, Eric; DeLisi, Matt; Hewitt, Ashley

    2017-06-01

    Sexual murderers perpetrate homicide and rape/sexual abuse, but it is unclear whether they should primarily be considered homicide offenders, sexual offenders, or both. Most studies have merged together different types of non-homicidal sex offenders (NHSOs), neglecting to consider the potential differences between the nonviolent and violent sex offenders. Here, we suggest it is important to isolate those violent sex offenders who inflict severe physical injuries that could potentially lead to a lethal outcome. Therefore, the aim of the current study is to compare different measures of the criminal career on three groups of sex offenders: NHSOs, violent NHSOs, and sexual homicide offenders (SHOs) using data from 616 incarcerated male sex offenders in a Federal penitentiary in Canada. Interestingly, the group of sex offenders with the worst criminal career profile was not the SHOs, but the violent NHSOs. Violent NHSOs had the greatest number of prior convictions and the most varied and versatile criminal career. Therefore, we suggest that based on their criminal career, SHOs should be considered more as murderers than sex offenders. However, to fully answer this question, future studies should include a group of non-sexual homicide offenders.

  10. Sex and Management of Rheumatoid Arthritis.

    Science.gov (United States)

    Favalli, Ennio Giulio; Biggioggero, Martina; Crotti, Chiara; Becciolini, Andrea; Raimondo, Maria Gabriella; Meroni, Pier Luigi

    2018-01-26

    Rheumatoid arthritis (RA) is a chronic and progressive autoimmune disease more common in women than men (3:1). Although sex-based differences may play a complex role in promoting an autoimmune dysfunction, to date the comprehensive knowledge of the link between sex and RA is still partially lacking. Furthermore, males and females have been demonstrated to differently deal with their chronic pathologies, modifying the perceived sex-based burden of disease. Gender medicine is a newly approach focusing on the impact of gender differences on human physiology, pathophysiology, and clinical features of diseases, analyzing the complex interrelation and integration of sex and psychological and cultural behavior. A better comprehension of possible factors influencing sexual dimorphism in RA susceptibility, pattern of presentation, disease activity, and outcome could contribute to a tailored approach, in order to limit the morbidity of the disease. RA disease activity seems to be higher in women, whereas the response rate to synthetic and biologic disease-modifying therapies appears to be better in males. Moreover, the common strategies for RA management may be affected by concomitant pregnancy or childbearing desire, with particular regard to treatments with potential teratogenic effects or impact on fertility. Finally, comorbidities, such as fibromyalgia, major depression, and osteoporosis, are more frequent in females, while the impact of sex on cardiovascular risk is still controversial. Moving from the role of sex in influencing RA pathogenesis, epidemiology, and disease characteristics, this review explores the evidence on how sex can have an impact on strategies for managing patients with RA.

  11. Sex education vital for Chinese adolescents.

    Science.gov (United States)

    Zhang, Z

    1997-02-01

    This article summarizes findings from a survey conducted among adolescents in Beijing and Tianjin, China. Findings indicate that 89.3% of sex offenders were adolescents. Many high school students were engaged in premarital sexual relations, but lacked knowledge about sex and contraception. Premarital sex and sexually transmitted diseases are considered a social evil. The central government has direct jurisdiction in Tianjin and its population of 9 million. By 1989 there were 540,000, or 12% of total population, aged 12-16 years. A survey of 3231 junior middle school students aged 11-14 years revealed that 35% of girls did not know why menstruation occurred at a certain age. About 55% of boys did not know about erections. 35% considered an erect penis a part of normal physical development, but over 50% were confused. 30-50% of students who had reached menarche and sexual maturity found it difficult to find knowledgeable people. 50% received information from the mass media. 44% of girls learned from their mothers. 25% of boys and girls aged 11-12 years already had girlfriends and boyfriends. About 30% desired friends of the opposite sex and desired intimacy, love, and dependability among friends. It is argued that the backward notions of sex originated in a once feudal society that considered sex a taboo. Parents, teachers, and school authorities are resistant to introducing sex education; teachers are embarrassed by the subject matter. In Beijing about 4000 students aged 11-14 years were interviewed. These students had limited information on sex-related issues and misconceptions. Attitudes must be changed and teachers must be trained before adolescent health and sex education can be introduced into schools. The government can play a role in promoting programs for adolescents and coordinating the efforts of nongovernmental groups.

  12. Risk of sex-specific cancers in opposite-sex and same-sex twins in Denmark and Sweden

    DEFF Research Database (Denmark)

    Ahrenfeldt, Linda Juel; Skytthe, Axel; Möller, Sören

    2015-01-01

    -scale prospective twin study compared opposite-sex (OS) and same-sex (SS) twins to test the impact of intrauterine exposures on cancer risk. Based on the Danish and Swedish twin and cancer registries, we calculated incidence rate ratios for OS and SS twins while standardized incidence ratios (SIRs) with 95......% confidence intervals (CIs) were calculated for OS/SS twins compared with the general population. RESULTS: A total of 18,001 cancers were identified during 1943-2009. No significant differences were observed between OS and SS twins, neither for the sex-specific cancers nor for cancer at all sites. All...... to prenatal testosterone - does not increase the risk of sex-specific cancers in OS females. Furthermore, the study supports that twinning per se is not a risk factor of cancer. IMPACT: Findings are reassuring as they fail to provide evidence for the hypothesis that endocrine or other difference...

  13. Molecular study of developmental sex disorders in children

    African Journals Online (AJOL)

    Soheir S. AboElella

    2015-03-07

    Mar 7, 2015 ... development, causing divergences between genetic sex, gonadal sex and phenotypic sex ... neonatal history of failure to thrive, vomiting, skin pigmen- tations and .... of them (12 & 14) suffered from hypoglycemia. Hormonal ...

  14. Genetics Home Reference: 46,XX testicular disorder of sex development

    Science.gov (United States)

    ... 46,XX testicular disorder of sex development 46,XX testicular disorder of sex development Printable PDF Open ... to view the expand/collapse boxes. Description 46,XX testicular disorder of sex development is a condition ...

  15. Globalization and male sex trade in Ghana: Modernity or Immorality ...

    African Journals Online (AJOL)

    Globalization and male sex trade in Ghana: Modernity or Immorality? ... apolitical and less hypocritical way of discussing the issue devoid of criminalization, in the ... Key words: Globalization, homosexuality, male sex trade, sex culture, Ghana.

  16. Sex Robots: Between Human and Artificial

    OpenAIRE

    Richardson, Kathleen

    2017-01-01

    Despite a surplus of human beings in the world, new estimates total 7 and a half billion, we appear to be at the start of an attachment crisis - a crisis in how human beings make intimate relationships. Enter the sex robots, built out of the bodies of sex dolls to help humans, particularly males escape their inability to connect. What does the rise of sex robots tell us about the way that women and girls are imagined, are they persons or property? And to what extent is porn, prostitution and ...

  17. Treating infidelity in same-sex couples.

    Science.gov (United States)

    Martell, Christopher R; Prince, Stacey E

    2005-11-01

    Psychotherapy with same-sex couples does not differ markedly from standard couple therapies; this is also true for treating couples facing infidelity. However, same-sex couples often design their relationships differently, without tradition and formal marital contracts to prescribe behavior. Based on clinical experience and the empirical research, this article addresses the differing norms involved in affirmatively treating infidelity in gay and lesbian couples within the framework of integrative behavioral couple therapy (IBCT). Two cases illustrate the process and outcome of IBCT with same-sex couples.

  18. Same-sex marriage and mental health.

    Science.gov (United States)

    Liangas, Georgios; Athanasou, James A

    2016-12-01

    It has been proposed that legislation for same-sex marriage has a positive mental health benefit. The purpose of this paper is to review and evaluate the empirical and conceptual links between same-sex marriage and mental health. There are substantive methodological issues in the four surveys and comparisons undertaken. Difficulties with the validity of the evidence are discussed. Conceptual difficulties in the arguments relating to victimisation as well as the psychology of marriage are highlighted. It was concluded that it is premature to make claims of causality vis-a-vis same-sex marriage legislation and mental health. © The Royal Australian and New Zealand College of Psychiatrists 2016.

  19. Cretaceous park of sex determination: sex chromosomes are conserved across iguanas.

    Science.gov (United States)

    Rovatsos, Michail; Pokorná, Martina; Altmanová, Marie; Kratochvíl, Lukáš

    2014-03-01

    Many poikilothermic vertebrate lineages, especially among amphibians and fishes, possess a rapid turnover of sex chromosomes, while in endotherms there is a notable stability of sex chromosomes. Reptiles in general exhibit variability in sex-determining systems; as typical poikilotherms, they might be expected to have a rapid turnover of sex chromosomes. However, molecular data which would enable the testing of the stability of sex chromosomes are lacking in most lineages. Here, we provide molecular evidence that sex chromosomes are highly conserved across iguanas, one of the most species-rich clade of reptiles. We demonstrate that members of the New World families Iguanidae, Tropiduridae, Leiocephalidae, Phrynosomatidae, Dactyloidae and Crotaphytidae, as well as of the family Opluridae which is restricted to Madagascar, all share homologous sex chromosomes. As our sampling represents the majority of the phylogenetic diversity of iguanas, the origin of iguana sex chromosomes can be traced back in history to the basal splitting of this group which occurred during the Cretaceous period. Iguanas thus show a stability of sex chromosomes comparable to mammals and birds and represent the group with the oldest sex chromosomes currently known among amniotic poikilothermic vertebrates.

  20. Heritable Variation for Sex Ratio under Environmental Sex Determination in the Common Snapping Turtle (Chelydra Serpentina)

    Science.gov (United States)

    Janzen, F. J.

    1992-01-01

    The magnitude of quantitative genetic variation for primary sex ratio was measured in families extracted from a natural population of the common snapping turtle (Chelydra serpentina), which possesses temperature-dependent sex determination (TSD). Eggs were incubated at three temperatures that produced mixed sex ratios. This experimental design provided estimates of the heritability of sex ratio in multiple environments and a test of the hypothesis that genotype X environment (G X E) interactions may be maintaining genetic variation for sex ratio in this population of C. serpentina. Substantial quantitative genetic variation for primary sex ratio was detected in all experimental treatments. These results in conjunction with the occurrence of TSD in this species provide support for three critical assumptions of Fisher's theory for the microevolution of sex ratio. There were statistically significant effects of family and incubation temperature on sex ratio, but no significant interaction was observed. Estimates of the genetic correlations of sex ratio across environments were highly positive and essentially indistinguishable from +1. These latter two findings suggest that G X E interaction is not the mechanism maintaining genetic variation for sex ratio in this system. Finally, although substantial heritable variation exists for primary sex ratio of C. serpentina under constant temperatures, estimates of the effective heritability of primary sex ratio in nature are approximately an order of magnitude smaller. Small effective heritability and a long generation time in C. serpentina imply that evolution of sex ratios would be slow even in response to strong selection by, among other potential agents, any rapid and/or substantial shifts in local temperatures, including those produced by changes in the global climate. PMID:1592234

  1. Sex ratio variation in the bumblebee Bombus terrestris

    DEFF Research Database (Denmark)

    Duchateau, Marie José; Velthuis, Hayo H. W.; Boomsma, Jacobus Jan

    2004-01-01

    Bombus terrestris, bumblebees, colony development, queen control, reproductive strategies, sex allocation......Bombus terrestris, bumblebees, colony development, queen control, reproductive strategies, sex allocation...

  2. Temporal genomic evolution of bird sex chromosomes

    DEFF Research Database (Denmark)

    Wang, Zongji; Zhang, Jilin; Yang, Wei

    2014-01-01

    BACKGROUND: Sex chromosomes exhibit many unusual patterns in sequence and gene expression relative to autosomes. Birds have evolved a female heterogametic sex system (male ZZ, female ZW), through stepwise suppression of recombination between chrZ and chrW. To address the broad patterns and complex...... driving forces of Z chromosome evolution, we analyze here 45 newly available bird genomes and four species' transcriptomes, over their course of recombination loss between the sex chromosomes. RESULTS: We show Z chromosomes in general have a significantly higher substitution rate in introns and synonymous...... ('fast-Z' evolution). And species with a lower level of intronic heterozygosities tend to evolve even faster on the Z chromosome. Further analysis of fast-evolving genes' enriched functional categories and sex-biased expression patterns support that, fast-Z evolution in birds is mainly driven by genetic...

  3. Have sex or not? Lessons from bacteria.

    Science.gov (United States)

    Lodé, T

    2012-01-01

    Sex is one of the greatest puzzles in evolutionary biology. A true meiotic process occurs only in eukaryotes, while in bacteria, gene transcription is fragmentary, so asexual reproduction in this case really means clonal reproduction. Sex could stem from a signal that leads to increased reproductive output of all interacting individuals and could be understood as a secondary consequence of primitive metabolic reactions. Meiotic sex evolved in proto-eukaryotes to solve a problem that bacteria did not have, namely a large amount of DNA material, occurring in an archaic step of proto-cell formation and genetic exchanges. Rather than providing selective advantages through reproduction, sex could be thought of as a series of separate events which combines step-by-step some very weak benefits of recombination, meiosis, gametogenesis and syngamy. Copyright © 2012 S. Karger AG, Basel.

  4. Sex determination: insights from the silkworm

    Indian Academy of Sciences (India)

    2010-09-06

    determination pathway that controls most sex-specific phenotypes, is a .... Sports and Culture, Government of Japan, grant-in-aid for Young. Scientists ... Berghammer A. J., Klingler M. and Wimmer E. A. 1999 A universal marker for ...

  5. Sex determination: ways to evolve a hermaphrodite.

    OpenAIRE

    Braendle , Christian; Félix , Marie-Anne

    2006-01-01

    Most species of the nematode genus Caenorhabditis reproduce through males and females; C. elegans and C. briggsae, however, produce self-fertile hermaphrodites instead of females. These transitions to hermaphroditism evolved convergently through distinct modifications of germline sex determination mechanisms.

  6. Sexing code subversion, theory and representation

    CERN Document Server

    Herbst, Claudia

    2008-01-01

    Critically investigating the gender of programming in popular culture, Sexing Code proposes that the de facto representation of technical ability serves to perpetuate the age-old association of the male with intellect and reason, while identifying the fem

  7. Sex hormone replacement in Turner syndrome

    DEFF Research Database (Denmark)

    Trolle, Christian; Hjerrild, Britta; Cleemann, Line Hartvig

    2012-01-01

    The cardinal features of Turner syndrome (TS) are short stature, congenital abnormalities, infertility due to gonadal dysgenesis, with sex hormone insufficiency ensuing from premature ovarian failure, which is involved in lack of proper development of secondary sex characteristics and the frequent...... osteoporosis seen in Turner syndrome. But sex hormone insufficiency is also involved in the increased cardiovascular risk, state of physical fitness, insulin resistance, body composition, and may play a role in the increased incidence of autoimmunity. Severe morbidity and mortality affects females with Turner...... syndrome. Recent research emphasizes the need for proper sex hormone replacement therapy (HRT) during the entire lifespan of females with TS and new hypotheses concerning estrogen receptors, genetics and the timing of HRT offers valuable new information. In this review, we will discuss the effects...

  8. Genetic sexing of the Mediterranean fruit fly

    International Nuclear Information System (INIS)

    1990-01-01

    In the early 1980s, it was recognized by the FAO and the IAEA that a genetic sexing method for the Mediterranean fruit fly (medfly) would greatly improve the efficacy of the medfly sterile insect technique (SIT) and reduce its costs. These Proceedings summarize the research and development findings of the Agency's co-operators in the co-ordinated research programme to develop a genetic sexing method for the medfly. Great progress has been made in many aspects of medfly genetics. including the development of a number of genetic sexing strains. Contents: Genetics, Cytogenetics and Population Genetics. Genetic Sexing of Ceratitis Capitata by Morphological, Biochemical and other means. Recommendations. Refs, figs and tabs

  9. Determining sex ratios of turtle hatchlings

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Previous status assessments of marine turtles have assumed that the natural sex ratio of a marine turtle population is 1:1 (e.g. Conant et al. 2009). However, this...

  10. Sex work on the rise. International news.

    Science.gov (United States)

    1996-01-01

    The AIDS epidemic has brought to the fore many social injustices; for instance, inappropriate laws. The groups of people most at risk of HIV/AIDS are women, young people, and sex workers. More appropriate laws are needed to protect their rights. In many instances sex workers are prosecuted for selling their services, but their clients are not prosecuted for seeking these services. Most people become sex workers so they can feed, clothe, and supply the basic needs for themselves and their families. Many sex workers are abandoned wives, mothers with no means of support, and poverty stricken people. A Health Ministry commission in Sweden proposed that prostitutes, clients, and pimps be prosecuted and be liable to imprisonment. Authorities in Scotland, where prostitution is illegal, have granted licenses to more than 20 clubs in Edinburgh in which sex is for sale. In the UK, the Royal College of Nursing called for a measure to decriminalize prostitution and to introduce licensed, regulated brothels. The legalization of sex clubs and brothels will occur soon in the Netherlands. In Poland, 30,000-50,000 youth, 33% of whom are underage, sell sex during holidays. Organizations are beginning to work only with male prostitutes in Belgium. In the countries of the former Soviet Union and China, prostitution is becoming more and more common. Some young girls in these countries practice currency prostitution. In almost all Asian countries except Thailand condom use is low; yet prostitution and sexually transmitted diseases are very common. Some people participate in the corrupt trade in women from Nepal to supply the sex market in Bombay, India. Sex tourism is still common in cities of Eastern Europe and the former USSR and in areas where tourism is increasing. There are more than 1 million prostitutes aged under 16 in eight Asian countries, with 400,000 in India. Sweden and the UK have taken steps to prosecute natives who have sex with children abroad. Philippine authorities

  11. Invited review: sex ratio and rheumatic disease.

    Science.gov (United States)

    Lockshin, M D

    2001-11-01

    Human illnesses affect men and women differently. In some cases (diseases of sex organs, diseases resulting from X or Y chromosome mutations), reasons for sex discrepancy are obvious, but in other cases no reason is apparent. Explanations for sex discrepancy of illness occur at different biological levels: molecular (e.g., imprinting, X-inactivation), cellular (sex-specific receptor activity), organ (endocrine influences), whole organism (size, age), and environmental-behavioral, including intrauterine influences. Autoimmunity represents a prototypical class of illness that has high female-to-male (F/M) ratios. Although the F/M ratios in autoimmune diseases are usually attributed to the influence of estrogenic hormones, evidence demonstrates that the attributed ratios are imprecise and that definitions and classifications of autoimmune diseases vary, rendering at least part of the counting imprecise. In addition, many studies on sex discrepancy of human disease fail to distinguish between disease incidence and disease severity. In April 2001, the Institute of Medicine of the National Academy of Sciences published Exploring the Biological Contributions to Human Health: Does Sex Matter? (Wizemann T and Pardue M-L, editors). This minireview summarizes the section of that report that concerns autoimmune and infectious disease. Some thyroid, rheumatic, and hepatic autoimmune diseases have high F/M ratios, whereas others have low. Those that have high ratios occur primarily in young adulthood. Gonadal hormones, if they play a role, likely do so through a threshold or permissive mechanism. Examples of sex differences that could be caused by environmental exposure, X inactivation, imprinting, X or Y chromosome genetic modulators, and intrauterine influences are presented as alternate, theoretical, and largely unexplored explanations for sex differences of incidence. The epidemiology of autoimmune diseases (young, female) suggests that an explanation for sex discrepancy of

  12. Gender Stereotypes in Same-Sex Relationships

    OpenAIRE

    Bro, Jesper Koch; Jensen, Ditte; Stokholm, Martin Valdemar Sachse; Kristoffersen, Simone Ryegaard; Tranberg, Line Falk

    2008-01-01

    Abstract Through five qualitative interviews with people that currently are or have been in same-sex relationship, analyzed by applying the theories of social constructivism by Peter L. Berger and Thomas Luckmann and Queer theorist Judith Butler, the project explores heterosexual stereotypes in same-sex relationships. The result is a thoroughgoing analysis where it appears from the interviews as if the interviewed people reproduce heterosexual stereotypical gender roles in their relationships...

  13. Sex determination in mythology and history.

    Science.gov (United States)

    Mittwoch, Ursula

    2005-02-01

    The history of ideas on how the sexes became divided spans at least three thousand years. The biblical account of the origin of Eve, and the opinions of the philosophers of classical Greece, have unexpected bearings on present-day ideas. The scientific study of sex determination can be said to have begun in the 17th century with the discovery of spermatozoa, but the origin and function of the "spermatic animalcules" eluded investigators until 1841. The mammalian egg was discovered in 1827, and in the last quarter of the century fertilization was observed. The view current at that time, that sex determination was under environmental control, gave way to the idea of chromosomal determination in the first quarter of the 20th century. The study of human and other mammalian chromosomes during the third quarter of the century, and the discovery of sex-chromosome abnormalities, emphasized the importance of the Y chromosome for male sex determination. The last quarter of the century witnessed a hunt for the "testis-determining" gene, thought to be responsible for the differentiation of Sertoli cells, and culminating in the isolation of SRY (Sry in the mouse). However, an increasing number of additional genes and growth factors were found to be required for the establishment of male sex. During the same period evidence emerged that male development was accompanied by enhanced growth, both of gonads and whole embryos. An unexpected finding was the demonstration of temperature-dependent sex determination in reptiles. With the advent of the 21st century, it was shown that Sry induces cell proliferation in fetal mouse gonads, and it has been suggested that male sex differentiation in mammals requires a higher metabolic rate. These insights could lead to a better understanding and improved treatment of abnormalities of sexual development.

  14. Atomoxetine in abstinent cocaine users: Sex differences

    Directory of Open Access Journals (Sweden)

    Elise E. DeVito

    2017-10-01

    Full Text Available Data presented are from a sex-differences secondary analysis of a human laboratory investigation of single doses of atomoxetine (40 mg and 80 mg versus placebo in abstinent individuals with cocaine use disorders (CUD. Subjective drug effects, cognitive performance and cardiovascular measures were assessed. The primary atomoxetine dose analyses (which do not consider sex as a factor are reported in full elsewhere (DeVito et al., 2017 [1].

  15. Sex Differences in Attitudes toward Partner Infidelity

    OpenAIRE

    Michael J. Tagler; Heather M. Jeffers

    2013-01-01

    Sex differences in reactions to partner infidelity have often been studied by comparing emotional reactions to scenarios of sexual versus emotional infidelity. Men, relative to women, tend to react with more distress to partner sexual infidelity than to emotional infidelity. Evolutionary theorists interpret this difference as evidence of sexually dimorphic selection pressures. In contrast, focusing only on the simple effects within each sex, social-cognitive theorists suggest that men and wom...

  16. The Argument for Same-Sex Marriage

    OpenAIRE

    Widiss, Deborah; Tebbe, Nelson; Gilreath, Shannon

    2018-01-01

    159 University of Pennsylvania Law Review PENNumbra 21 (2010) Professors Tebbe and Widiss revisit the arguments they made in "Equal Access and the Right to Marry" and emphasize their belief that distinguishing between different-sex marriage and same-sex marriage is inappropriate. They lament the sustained emphasis on the equal-protection and substantive-due-process challenges in the Perry litigation and suggest that an equal-access approach is more likely to be successful on appeal. Professor...

  17. Sex, Drugs, and Cognition: Effects of Marijuana†

    OpenAIRE

    Anderson, Beth M.; Rizzo, Matthew; Block, Robert I.; Pearlson, Godfrey D.; O'Leary, Daniel S.

    2010-01-01

    Despite the knowledge that many drugs affect men and women differently, few studies exploring the effects of marijuana use on cognition have included women. Findings from both animal and human studies suggest marijuana may have more marked effects in women. This study examined sex differences in the acute effects of marijuana on cognition in 70 (n= 35 male, 35 female) occasional users of marijuana. Tasks were chosen to tap a wide variety of cognitive domains affected by sex and/or marijuana i...

  18. Voting on pensions: sex and marriage

    OpenAIRE

    Leroux, Marie-Louise; Pestieau, Pierre; Racionero, Maria

    2009-01-01

    Existing political economy models of pensions focus on age and productivity. In this paper we incorporate two additional individual characteristics: sex and marital status. We ignore the role of age, by assuming that people vote at the start of their life, and characterize the preferred rate of taxation that finances a Beveridgean pension scheme when individuals differ in wage, sex and marital status. We allow for two types of couples: one-breadwinner and two-breadwinner couples. Marriage poo...

  19. Sex differences in intracranial arterial bifurcations

    DEFF Research Database (Denmark)

    Lindekleiv, Haakon M; Valen-Sendstad, Kristian; Morgan, Michael K

    2010-01-01

    Subarachnoid hemorrhage (SAH) is a serious condition, occurring more frequently in females than in males. SAH is mainly caused by rupture of an intracranial aneurysm, which is formed by localized dilation of the intracranial arterial vessel wall, usually at the apex of the arterial bifurcation. T....... The female preponderance is usually explained by systemic factors (hormonal influences and intrinsic wall weakness); however, the uneven sex distribution of intracranial aneurysms suggests a possible physiologic factor-a local sex difference in the intracranial arteries....

  20. Parent-adolescent sex communication in China.

    Science.gov (United States)

    Zhang, Liying; Li, Xiaoming; Shah, Iqbal H; Baldwin, Wendy; Stanton, Bonita

    2007-06-01

    Communication concerning sexual matters between parents and their adolescent children serve as a protective factor and exerts a favourable influence on adolescents' sexual behaviours. As limited data regarding parent-adolescent sex communication are available in China, this study was undertaken with the aim of exploring the patterns and related factors of such communication and its relationship with adolescent sexual behaviour. Community-based data were collected in 2001 in Changchun, China. Unmarried adolescents 15-19 years of age (322 young men and 360 young women) were included in a survey using self-administered questionnaires. Overall, sex communication with parents was relatively infrequent. There was a significant gender difference in the pattern of sex communication, with male adolescents being more likely to talk with fathers and female adolescents with mothers. Logistic regression analysis revealed that gender of adolescents, quality of communication with mothers on general topics, and adolescent's perception of mother being the main source of sex knowledge were predictive of the level of sex communication between mother and her adolescent children. This study reveals that communication regarding sexual matters between parents and adolescents was limited in China. The quality of communication on general topics between parents and their adolescent children is one of the important factors related to sex communication between them. It is essential that Chinese parents are better informed and skilled to be involved, in addition to school and community, in the sex education of their adolescent children. They should be able to communicate appropriately on sex-related issues with them.

  1. Risk of epilepsy in opposite-sex and same-sex twins

    DEFF Research Database (Denmark)

    Mao, Yanyan; Ahrenfeldt, Linda Juel; Christensen, Kaare

    2018-01-01

    Background: There is a complex interaction between female and male sex hormones and the risk of epilepsy. Whether prenatal exposure to higher levels of sex hormones affects the development of epilepsy in childhood or later in life is not well known. The sex hormone environment of fetuses may...... be affected by the sex of the co-twin. We estimated the risk of epilepsy for twins with an opposite-sex (OS) co-twin compared with twins with a same-sex (SS) co-twin. Methods: From the Danish Twin Registry, we identified OS female twins (n = 11,078), SS female twins (n = 19,186), OS male twins (n = 11...

  2. Childhood Adversity, Daily Stress, and Marital Strain in Same-Sex and Different-Sex Marriages

    Science.gov (United States)

    Donnelly, Rachel; Umberson, Debra; Kroeger, Rhiannon A.

    2017-01-01

    Childhood adversity has enduring consequences for individuals throughout life, including increased reactivity to stress that may contribute to marital strain in adulthood. Past research on gendered experiences of heterosexual spouses raises questions about how the influence of childhood adversity might differ for men and women in same-sex marriages. We analyze dyadic diary data from 756 individuals in 106 male same-sex, 157 female same-sex, and 115 different-sex marriages to consider how childhood adversity moderates the association between daily stress and marital strain. Results suggest that the negative consequences of daily stress for marital strain are amplified by past childhood adversity with variation for men and women in same- and different-sex unions, such that women and those in same-sex marriages may experience some protection from the adverse consequences of childhood adversity.

  3. Sex differences associated with intermittent swim stress.

    Science.gov (United States)

    Warner, Timothy A; Libman, Matthew K; Wooten, Katherine L; Drugan, Robert C

    2013-11-01

    Various animal models of depression have been used to seek a greater understanding of stress-related disorders. However, there is still a great need for novel research in this area, as many individuals suffering from depression are resistant to current treatment methods. Women have a higher rate of depression, highlighting the need to investigate mechanisms of sex differences. Therefore, we employed a new animal model to assess symptoms of depression, known as intermittent swim stress (ISS). In this model, the animal experiences 100 trials of cold water swim stress. ISS has already been shown to cause signs of behavioral depression in males, but has yet to be assessed in females. Following ISS exposure, we looked at sex differences in the Morris water maze and forced swim test. The results indicated a spatial learning effect only in the hidden platform task between male and female controls, and stressed and control males. A consistent spatial memory effect was only seen for males exposed to ISS. In the forced swim test, both sexes exposed to ISS exhibited greater immobility, and the same males and females also showed attenuated climbing and swimming, respectively. The sex differences could be due to different neural substrates for males and females. The goal of this study was to provide the first behavioral examination of sex differences following ISS exposure, so the stage of estrous cycle was not assessed for the females. This is a necessary future direction for subsequent experiments. The current article highlights the importance of sex differences in response to stress.

  4. Determination of sex by armbone dimensions.

    Science.gov (United States)

    Aye, Victor Omakoji

    2010-06-15

    Sex determination is a vital part of the medico-legal system but can be difficult in cases where the body is damaged. The purpose of this study was to develop a technique for sex determination from three arm-bone dimensions (wrist circumference, arm length and arm span). This knowledge can be applied in cases of mass disaster, homicide and events such as sports. Data were collected for 95 Nigerian male students and 90 Nigerian female students using physical anthropometry. Discriminant function presented the wrist dimension as the dominant contributor in this study. Combination equations for both the wrist and arm-span dimensions correctly classified sex (male/female) with an accuracy rate of 84.9%. On cross-validation, sex was also established with the same 84.9% accuracy rate. Sex determination was higher in males. Sexual dimorphism was established in this study, although the wrist circumference was more distinct than arm span; a combination of both generated sex with an accuracy prediction rate of 84.9%. (c) 2010 Elsevier Ireland Ltd. All rights reserved.

  5. Longevity enhances selection of environmental sex determination.

    Science.gov (United States)

    Bull, J J; Bulmer, M G

    1989-12-01

    Environmental sex determination (ESD) is a mechanism in which an individual develops as male or female largely in response to some environmental effect experienced early in life. Its forms range from sex determination by egg incubation temperature in reptiles to sex determination of photoperiod in amphipods. Previous theoretical work as suggested that ESD is favored by natural selection if the fitness consequences of the early environmental experience differ for males and females, so that an individual benefits by being male under some conditions and female under others. A drawback of ESD is that it enables climatic changes to influence the population sex ratio, and such fluctuations select against ESD. This study employed numerical analyses to investigate the balance between these two opposing forces. The negative impact of climatic fluctuations appears to depend greatly on species longevity: substantial between-year fluctuations are of little consequence in selecting against ESD in long-lived species because annual sex ratio fluctuations tend to cancel and thus alter the total population sex ratio only slightly. Thus, if a species is sufficiently long-lived, extreme ESD can be maintained despite only a weak advantage. This result offers one explanation for the failure to demonstrate an advantage for the extreme forms of ESD observed in reptiles.

  6. Association between asthma and female sex hormones.

    Science.gov (United States)

    Baldaçara, Raquel Prudente de Carvalho; Silva, Ivaldo

    2017-01-01

    The relationship between sex hormones and asthma has been evaluated in several studies. The aim of this review article was to investigate the association between asthma and female sex hormones, under different conditions (premenstrual asthma, use of oral contraceptives, menopause, hormone replacement therapy and pregnancy). Narrative review of the medical literature, Universidade Federal do Tocantins (UFT) and Universidade Federal de São Paulo (Unifesp). We searched the CAPES journal portal, a Brazilian platform that provides access to articles in the MEDLINE, PubMed, SciELO, and LILACS databases. The following keywords were used based on Medical Subject Headings: asthma, sex hormones, women and use of oral contraceptives. The associations between sex hormones and asthma remain obscure. In adults, asthma is more common in women than in men. In addition, mortality due to asthma is significantly higher among females. The immune system is influenced by sex hormones: either because progesterone stimulates progesterone-induced blocking factor and Th2 cytokines or because contraceptives derived from progesterone and estrogen stimulate the transcription factor GATA-3. The associations between asthma and female sex hormones remain obscure. We speculate that estrogen fluctuations are responsible for asthma exacerbations that occur in women. Because of the anti-inflammatory action of estrogen, it decreases TNF-α production, interferon-γ expression and NK cell activity. We suggest that further studies that highlight the underlying physiopathological mechanisms contributing towards these interactions should be conducted.

  7. The evolution of sex roles in birds is related to adult sex ratio

    OpenAIRE

    Liker, András; Freckleton, Robert P.; Székely, Tamás

    2013-01-01

    Sex-role reversal represents a formidable challenge for evolutionary biologists, since it is not clear which ecological, life-history or social factors facilitated conventional sex roles (female care and male-male competition for mates) to be reversed (male care and female-female competition). Classic theories suggested ecological or life-history predictors of role reversal, but most studies failed to support these hypotheses. Recent theory however predicts that sex-role reversal should be dr...

  8. Explorations of a Sex Therapy Question in Feminism : Feminist Interventions in Sex Therapy

    OpenAIRE

    Pernrud, Björn

    2007-01-01

    This study aims to investigate the consequences for feminist sex therapy that it is promoted as an alternative to a mainstream approach. Analytically I focus on the relation between normativity, claims to knowledge and professional legitimacy. I study sex therapeutic academic texts, and the material is approached through a framework developed by combining Donna Haraway’s concept of situated knowledges with elements from Karen Barad’s agential realism My analysis starts in feminist sex therapi...

  9. Combating human trafficking in the sex trade: can sex workers do it better?

    Science.gov (United States)

    Jana, Smarajit; Dey, Bharati; Reza-Paul, Sushena; Steen, Richard

    2014-12-01

    The dominant anti-trafficking paradigm conflates trafficking and sex work, denying evidence that most sex workers choose their profession and justifying police actions that disrupt communities, drive sex workers underground and increase vulnerability. We review an alternative response to combating human trafficking and child prostitution in the sex trade, the self-regulatory board (SRB) developed by Durbar Mahila Samanwaya Committee (DMSC, Sonagachi). DMSC-led interventions to remove minors and unwilling women from sex work account for over 80% of successful 'rescues' reported in West Bengal. From 2009 through 2011, 2195 women and girls were screened by SRBs: 170 (7.7%) minors and 45 (2.1%) unwilling adult women were assisted and followed up. The remaining 90.2% received counselling, health care and the option to join savings schemes and other community programmes designed to reduce sex worker vulnerability. Between 1992 and 2011 the proportion of minors in sex work in Sonagachi declined from 25 to 2%. With its universal surveillance of sex workers entering the profession, attention to rapid and confidential intervention and case management, and primary prevention of trafficking-including microcredit and educational programmes for children of sex workers-the SRB approach stands as a new model of success in anti-trafficking work. © The Author 2013. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. The evolution of sex chromosomes in organisms with separate haploid sexes.

    Science.gov (United States)

    Immler, Simone; Otto, Sarah Perin

    2015-03-01

    The evolution of dimorphic sex chromosomes is driven largely by the evolution of reduced recombination and the subsequent accumulation of deleterious mutations. Although these processes are increasingly well understood in diploid organisms, the evolution of dimorphic sex chromosomes in haploid organisms (U/V) has been virtually unstudied theoretically. We analyze a model to investigate the evolution of linkage between fitness loci and the sex-determining region in U/V species. In a second step, we test how prone nonrecombining regions are to degeneration due to accumulation of deleterious mutations. Our modeling predicts that the decay of recombination on the sex chromosomes and the addition of strata via fusions will be just as much a part of the evolution of haploid sex chromosomes as in diploid sex chromosome systems. Reduced recombination is broadly favored, as long as there is some fitness difference between haploid males and females. The degeneration of the sex-determining region due to the accumulation of deleterious mutations is expected to be slower in haploid organisms because of the absence of masking. Nevertheless, balancing selection often drives greater differentiation between the U/V sex chromosomes than in X/Y and Z/W systems. We summarize empirical evidence for haploid sex chromosome evolution and discuss our predictions in light of these findings. © 2015 The Author(s).

  11. Differences in Religiousness in Opposite-Sex and Same-Sex Twins in a Secular Society

    DEFF Research Database (Denmark)

    Juel Ahrenfeldt, Linda; Lindahl-Jacobsen, Rune; Möller, Sören

    2016-01-01

    (RCOPE) for the assessment of positive and negative religious coping patterns. Differences between OS and SS twins were investigated using logistic regression for each sex. The analyses were adjusted for dependence within twin pairs. No significant differences in religiousness and religious coping were......Sex differences in religion are well known, with females generally being more religious than males, and shared environmental factors have been suggested to have a large influence on religiousness. Twins from opposite-sex (OS) and same-sex (SS) pairs may differ because of a dissimilar psycho...

  12. Australian men's sexual practices in saunas, sex clubs and other male sex on premises venues.

    Science.gov (United States)

    Lyons, Anthony; Smith, Anthony M A; Grierson, Jeffrey W; von Doussa, Henry

    2010-06-01

    Sex on premises venues (SOPVs) where men have sex with men have been implicated in the spread of sexually transmissible infections, but few studies have described men's sexual encounters in SOPVs, particularly the degree to which men from different backgrounds engage in risky sexual practices. Interviewer administered surveys were conducted with 186 Australian men who have sex with men (MSM) within 48 h of visiting an SOPV. They reported their sexual practices, the characteristics of their partners and other circumstances surrounding their sexual encounters. All analyses were based on the number of sexual encounters (n = 430). Oral sex was the most common practice, occurring in 74.9% of encounters, followed by massage, frottage or kissing (53.7%), solo or mutual masturbation (36.3%), and anal sex (32.1%). Multivariate analyses revealed age as a significant factor for having protected anal sex (P = 0.001), insertive anal sex (P = 0.004) and receptive anal sex (P practices were more frequent in encounters among younger men, while masturbation (P = 0.03) was more frequent among older men. When men's sexual partners were affected by alcohol, encounters were less likely to involve unprotected anal intercourse (P = 0.006) and more likely to involve massage, frottage or kissing (P = 0.009). Men disclosed their HIV status in only 7.7% of encounters. With the likelihood of risky sexual practices varying according to background, results from this study should be used to guide interventions aiming to promote safer sex in SOPVs.

  13. Comparing Sex Buyers With Men Who Do Not Buy Sex: New Data on Prostitution and Trafficking.

    Science.gov (United States)

    Farley, Melissa; Golding, Jacqueline M; Matthews, Emily Schuckman; Malamuth, Neil M; Jarrett, Laura

    2015-08-31

    We investigated attitudes and behaviors associated with prostitution and sexual aggression among 101 men who buy sex and 101 age-, education-, and ethnicity-matched men who did not buy sex. Both groups tended to accept rape myths, be aware of harms of prostitution and trafficking, express ambivalence about the nature of prostitution, and believe that jail time and public exposure are the most effective deterrents to buying sex. Sex buyers were more likely than men who did not buy sex to report sexual aggression and likelihood to rape. Men who bought sex scored higher on measures of impersonal sex and hostile masculinity and had less empathy for prostituted women, viewing them as intrinsically different from other women. When compared with non-sex-buyers, these findings indicate that men who buy sex share certain key characteristics with men at risk of committing sexual aggression as documented by research based on the leading scientific model of the characteristics of non-criminal sexually aggressive men, the Confluence Model of sexual aggression. © The Author(s) 2015.

  14. Neurogenin 3 Mediates Sex Chromosome Effects on the Generation of Sex Differences in Hypothalamic Neuronal Development

    Directory of Open Access Journals (Sweden)

    Maria Julia Scerbo

    2014-07-01

    Full Text Available The organizational action of testosterone during critical periods of development is the cause of numerous sex differences in the brain. However, sex differences in neuritogenesis have been detected in primary neuronal hypothalamic cultures prepared before the peak of testosterone production by fetal testis. In the present study we assessed the hypothesis of that cell-autonomous action of sex chromosomes can differentially regulate the expression of the neuritogenic gene neurogenin 3 (Ngn3 in male and female hypothalamic neurons, generating sex differences in neuronal development. Neuronal cultures were prepared from male and female E14 mouse hypothalami, before the fetal peak of testosterone. Female neurons showed enhanced neuritogenesis and higher expression of Ngn3 than male neurons. The silencing of Ngn3 abolished sex differences in neuritogenesis, decreasing the differentiation of female neurons. The sex difference in Ngn3 expression was determined by sex chromosomes, as demonstrated using the four core genotypes mouse model, in which a spontaneous deletion of the testis-determining gene Sry from the Y chromosome was combined with the insertion of the Sry gene onto an autosome. In addition, the expression of Ngn3, which is also known to mediate the neuritogenic actions of estradiol, was increased in the cultures treated with the hormone, but only in those from male embryos. Furthermore, the hormone reversed the sex differences in neuritogenesis promoting the differentiation of male neurons. These findings indicate that Ngn3 mediates both cell-autonomous actions of sex chromosomes and hormonal effects on neuritogenesis.

  15. Love grows with sex: teenagers negotiating sex and gender in the context of HIV and the implications for sex education.

    Science.gov (United States)

    Bhana, Deevia

    2017-03-01

    How do teenagers located in the KwaZulu-Natal province of South Africa, the epicentre of the HIV pandemic, give meaning to sexuality? This paper examines teenage black Africans investments in sex and sexuality and the gendered dynamics through which sexuality is articulated. Whilst unequal gender relations of power continue to feature prominently within relationship dynamics fuelling the gendering of HIV, attention to the micro-processes through which relationships are forged remain significant in illustrating the complex connections between love, sex and gender. Drawing on empirical findings with teenagers between the ages of 16 and 17 years old, the paper shows how relationships are conceptualised based on discourses of love. Love is inextricably bound up with sex and when teenagers talk about love and sex they also talk about condom use, multiple sexual partners and gender inequalities. What teenagers were interested in for their sexual relationships was not raised in sex education programmes at school. Implications for addressing teenage constructions of sexuality are discussed in the conclusion.

  16. Genetic architecture and the evolution of sex.

    Science.gov (United States)

    Lohaus, Rolf; Burch, Christina L; Azevedo, Ricardo B R

    2010-01-01

    Theoretical investigations of the advantages of sex have tended to treat the genetic architecture of organisms as static and have not considered that genetic architecture might coevolve with reproductive mode. As a result, some potential advantages of sex may have been missed. Using a gene network model, we recently showed that recombination imposes selection for robustness to mutation and that negative epistasis can evolve as a by-product of this selection. These results motivated a detailed exploration of the mutational deterministic hypothesis, a hypothesis in which the advantage of sex depends critically on epistasis. We found that sexual populations do evolve higher mean fitness and lower genetic load than asexual populations at equilibrium, and, under moderate stabilizing selection and large population size, these equilibrium sexual populations resist invasion by asexuals. However, we found no evidence that these long- and short-term advantages to sex were explained by the negative epistasis that evolved in our experiments. The long-term advantage of sex was that sexual populations evolved a lower deleterious mutation rate, but this property was not sufficient to account for the ability of sexual populations to resist invasion by asexuals. The ability to resist asexual invasion was acquired simultaneously with an increase in recombinational robustness that minimized the cost of sex. These observations provide the first direct evidence that sexual reproduction does indeed select for conditions that favor its own maintenance. Furthermore, our results highlight the importance of considering a dynamic view of the genetic architecture to understand the evolution of sex and recombination.

  17. Mother's occupation and sex ratio at birth

    Directory of Open Access Journals (Sweden)

    Amiot Volodymyr

    2010-05-01

    Full Text Available Abstract Background Many women are working outside of the home, occupying a multitude of jobs with varying degrees of responsibilities and levels of psychological stress. We investigated whether different job types in women are associated with child sex at birth, with the hypothesis that women in job types, which are categorized as "high psychological stress" jobs, would be more likely to give birth to a daughter than a son, as females are less vulnerable to unfavourable conditions during conception, pregnancy and after parturition, and are less costly to carry to term. Methods We investigated the effects of mother's age, maternal and paternal job type (and associated psychological stress levels and paternal income on sex ratio at birth. Our analyses were based on 16,384 incidences of birth from a six-year (2000 to 2005 inclusive childbirth dataset from Addenbrooke's Hospital in Cambridge, UK. We obtained a restricted data set from Addenbrooke's hospital with: maternal age, maternal and paternal occupations, and whether or not the child was first-born. Results Women in job types that were categorized as "high stress" were more likely to give birth to daughters, whereas women in job types that were categorized as "low stress" had equal sex ratios or a slight male bias in offspring. We also investigated whether maternal age, and her partner's income could be associated with reversed offspring sex ratio. We found no association between mother's age, her partner's job stress category or partner income on child sex. However, there was an important interaction between job stress category and partner income in some of the analyses. Partner income appears to attenuate the association between maternal job stress and sex ratios at moderate-income levels, and reverse it at high-income levels. Conclusions To our knowledge this is the first report on the association between women's job type stress categories and offspring sex ratio in humans, and the

  18. Cerebral sex dimorphism and sexual orientation.

    Science.gov (United States)

    Manzouri, Amirhossein; Savic, Ivanka

    2018-03-01

    The neurobiology of sexual orientation is frequently discussed in terms of cerebral sex dimorphism (defining both functional and structural sex differences). Yet, the information about possible cerebral differences between sex-matched homo and heterosexual persons is limited, particularly among women. In this multimodal MRI study, we addressed these issues by investigating possible cerebral differences between homo and heterosexual persons, and by asking whether there is any sex difference in this aspect. Measurements of cortical thickness (Cth), subcortical volumes, and functional and structural resting-state connections among 40 heterosexual males (HeM) and 40 heterosexual females (HeF) were compared with those of 30 homosexual males (HoM) and 30 homosexual females (HoF). Congruent with previous reports, sex differences were detected in heterosexual controls with regard to fractional anisotropy (FA), Cth, and several subcortical volumes. Homosexual groups did not display any sex differences in FA values. Furthermore, their functional connectivity was significantly less pronounced in the mesial prefrontal and precuneus regions. In these two particular regions, HoM also displayed thicker cerebral cortex than other groups, whereas HoF did not differ from HeF. In addition, in HoM the parietal Cth showed "sex-reversed" values, not observed in HoF. Homosexual orientation seems associated with a less pronounced sexual differentiation of white matter tracts and a less pronounced functional connectivity of the self-referential networks compared to heterosexual orientation. Analyses of Cth suggest that male and female homosexuality are not simple analogues of each other and that differences from heterosexual controls are more pronounced in HoM. © 2017 Wiley Periodicals, Inc.

  19. Commercial sex venues, syphilis and methamphetamine use among female sex workers.

    Science.gov (United States)

    Kang, Dianming; Liao, Meizhen; Jiang, Zhenxia; Zhang, Xijiang; Mao, Wenwen; Zhang, Ning; Tao, Xiaorun; Huang, Tao; Bi, Zhenqiang; Aliyu, Muktar; Wu, Pingsheng; Jiang, Baofa; Jia, Yujiang

    2011-06-01

    The objective of this study was to assess the factors associated with methamphetamine (MA) use, syphilis, and unprotected sex among female sex workers from different type of venues in Qingdao City, Shandong Province of China. Three consecutive cross-sectional surveys provided information on demographics, sexual and drug use behaviors, and HIV-related services. Of 1187 participants, 3.0% were infected with syphilis; 30.2% ever used MA; 58.3% ever had unprotected commercial sex in the past month. The prevalence rates of syphilis and MA use were 2.5% and 33.0% for participants recruited from saunas, night clubs, bars or hotels; 2.7% and 28.3% for hair/beauty salon-based participants; and 4.5% and 15.8% for street-based participants. Street-based MA users were more likely to be single, non-Shandong residents, have first lifetime sex act at younger age, and recruited in 2008 (vs. 2006). Saunas, night clubs, bars, or hotels-based MA users were more likely to be younger, sex debut at younger age, have longer duration of sex work, have unprotected commercial sex, and be syphilis-infected. Hair/beauty salon-based MA users were more likely to be non-Shandong residents, younger, and to have unprotected commercial sex. Syphilis among the sauna-, night club-, bar-, or hotel-based participants was associated with MA use and ever receipt of HIV testing. Syphilis among the hair/beauty salon-based participants was associated with longer duration of sex work. MA users who frequent commercial sex venues are engaging in high-risk behaviors and are at risk for syphilis/other sexually transmitted diseases. Better-targeted intervention efforts to curtail the epidemics of MA use and HIV/syphilis should therefore take cognizance of the role of commercial sex venues as focal points of MA use and syphilis/sexually transmitted disease transmission.

  20. Using technology, choosing sex. The campaign against sex determination and the question of choice.

    Science.gov (United States)

    1992-01-01

    Women's groups and people's science and health groups formed the Forum Against Sex Determination and Sex Pre-Selection in November 1985 in Bombay, India, to prevent sex determination and sex preselection tests. The Forum considered sex determination and sex preselection to be an abuse of science and technology against people, especially women. Between 1901 and 1991, the sex ratio fell from 972 females/1000 males to 929/1000. The Forum saw the issue of sex determination and sex preselection as a link to oppression of and discrimination against females in all sectors of society. It also believed this to be a human rights issue. The Forum lobbied for a law regulating diagnostic techniques without banning them, since determining chromosomal abnormalities is important. The State of Maharashtra passed such a law in June 1988. It had some provisions which were counter-productive, however. For example, women undergoing a sex determination test must pay a fine of Rs 5 if found guilty of planning to terminate a pregnancy of a female fetus. Yet, neither the husband nor parents-in-law are liable, even though they often pressure women to undergo sex determination tests. The Forum's efforts and enactment of the law in Maharashtra have prompted other state governments and the central government to propose similar legislation. These state governments include Goa, Gujarat, and Orissa. The central government has met with organizations and individuals lobbying against misuse of diagnostic tests to obtain their counsel. The Forum does not feel comfortable with state control, however, since it tends to consider government to be against the people. Yet, the Forum did want the state to protect women's interests. It has raised important questions about technology, particularly concerning criteria to determine desirable and appropriate technologies.

  1. Gender-stereotyping and cognitive sex differences in mixed- and same-sex groups.

    Science.gov (United States)

    Hirnstein, Marco; Coloma Andrews, Lisa; Hausmann, Markus

    2014-11-01

    Sex differences in specific cognitive abilities are well documented, but the biological, psychological, and sociocultural interactions that may underlie these differences are largely unknown. We examined within a biopsychosocial approach how gender stereotypes affect cognitive sex differences when adult participants were tested in mixed- or same-sex groups. A total of 136 participants (70 women) were allocated to either mixed- or same-sex groups and completed a battery of sex-sensitive cognitive tests (i.e., mental rotation, verbal fluency, perceptual speed) after gender stereotypes or gender-neutral stereotypes (control) were activated. To study the potential role of testosterone as a mediator for group sex composition and stereotype boost/threat effects, saliva samples were taken before the stereotype manipulation and after cognitive testing. The results showed the typical male and female advantages in mental rotation and verbal fluency, respectively. In general, men and women who were tested in mixed-sex groups and whose gender stereotypes had not been activated performed best. Moreover, a stereotype threat effect emerged in verbal fluency with reduced performance in gender stereotyped men but not women. Testosterone levels did not mediate the effects of group sex composition and stereotype threat nor did we find any relationship between testosterone and cognitive performance in men and women. Taken together, the findings suggest that an interaction of gender stereotyping and group sex composition affects the performance of men and women in sex-sensitive cognitive tasks. Mixed-sex settings can, in fact, increase cognitive performance as long as gender-stereotyping is prevented.

  2. Using RAD-seq to recognize sex-specific markers and sex chromosome systems.

    Science.gov (United States)

    Gamble, Tony

    2016-05-01

    Next-generation sequencing methods have initiated a revolution in molecular ecology and evolution (Tautz et al. ). Among the most impressive of these sequencing innovations is restriction site-associated DNA sequencing or RAD-seq (Baird et al. ; Andrews et al. ). RAD-seq uses the Illumina sequencing platform to sequence fragments of DNA cut by a specific restriction enzyme and can generate tens of thousands of molecular genetic markers for analysis. One of the many uses of RAD-seq data has been to identify sex-specific genetic markers, markers found in one sex but not the other (Baxter et al. ; Gamble & Zarkower ). Sex-specific markers are a powerful tool for biologists. At their most basic, they can be used to identify the sex of an individual via PCR. This is useful in cases where a species lacks obvious sexual dimorphism at some or all life history stages. For example, such tests have been important for studying sex differences in life history (Sheldon ; Mossman & Waser ), the management and breeding of endangered species (Taberlet et al. ; Griffiths & Tiwari ; Robertson et al. ) and sexing embryonic material (Hacker et al. ; Smith et al. ). Furthermore, sex-specific markers allow recognition of the sex chromosome system in cases where standard cytogenetic methods fail (Charlesworth & Mank ; Gamble & Zarkower ). Thus, species with male-specific markers have male heterogamety (XY) while species with female-specific markers have female heterogamety (ZW). In this issue, Fowler & Buonaccorsi () illustrate the ease by which RAD-seq data can generate sex-specific genetic markers in rockfish (Sebastes). Moreover, by examining RAD-seq data from two closely related rockfish species, Sebastes chrysomelas and Sebastes carnatus (Fig. ), Fowler & Buonaccorsi () uncover shared sex-specific markers and a conserved sex chromosome system. © 2016 John Wiley & Sons Ltd.

  3. Sex Role Stereotyping in Saturday Morning Cartoon Shows.

    Science.gov (United States)

    Mayes, Sandra L.; Valentine, K. B.

    1979-01-01

    Explores the role children's cartoon programs may play in forming sex role identities in children through the presentation of sex-typed personality attributes of the cartoon characters. Fourteen dependent variables of cartoon character personality were analyzed by sex of the character and sex of the viewer. (JVP)

  4. Sex Education Knowledge Differences between Freshmen and Senior College Undergraduates

    Science.gov (United States)

    Franklin, Ruth M.; Dotger, Sharon

    2011-01-01

    Abstinence sexuality education (sex ed) is the only federally funded sex ed in the United States. The strict curriculum of this education does not educate American adolescents about safer sex practices and leaves a knowledge gap in these adolescents that follows them into college. The Problem: This project aimed to identify sex knowledge…

  5. Compensated for Life: Sex Work and Disease Risk

    Science.gov (United States)

    Arunachalam, Raj; Shah, Manisha

    2013-01-01

    Sex workers draw a premium for engaging in unprotected sex. We theoretically motivate a test of whether this premium represents a compensating differential for disease, thereby mitigating sex workers' propensity to use condoms. Using transaction-level data and biological STI markers from sex workers in Ecuador, we exploit within-worker variation…

  6. On the origin of sex chromosomes from meiotic drive

    Science.gov (United States)

    Úbeda, Francisco; Patten, Manus M.; Wild, Geoff

    2015-01-01

    Most animals and many plants make use of specialized chromosomes (sex chromosomes) to determine an individual's sex. Best known are the XY and ZW sex-determination systems. Despite having evolved numerous times, sex chromosomes present something of an evolutionary puzzle. At their origin, alleles that dictate development as one sex or the other (primitive sex chromosomes) face a selective penalty, as they will be found more often in the more abundant sex. How is it possible that primitive sex chromosomes overcome this disadvantage? Any theory for the origin of sex chromosomes must identify the benefit that outweighs this cost and enables a sex-determining mutation to establish in the population. Here we show that a new sex-determining allele succeeds when linked to a sex-specific meiotic driver. The new sex-determining allele benefits from confining the driving allele to the sex in which it gains the benefit of drive. Our model requires few special assumptions and is sufficiently general to apply to the evolution of sex chromosomes in outbreeding cosexual or dioecious species. We highlight predictions of the model that can discriminate between this and previous theories of sex-chromosome origins. PMID:25392470

  7. Need for Studies of Sex Discrimination in Public Schools. Revised.

    Science.gov (United States)

    Citizens Advisory Council on the Status of Women, Washington, DC.

    This memorandum reviews the need for studies on sex discrimination in public schools and suggests groups that should make local reviews and those areas which need reviewing -- one sex schools; one sex or practically one sex courses; physical education, sports, and other extracurricular activities; textbooks, library books, and other curricular…

  8. Contact networks structured by sex underpin sex-specific epidemiology of infection.

    Science.gov (United States)

    Silk, Matthew J; Weber, Nicola L; Steward, Lucy C; Hodgson, David J; Boots, Mike; Croft, Darren P; Delahay, Richard J; McDonald, Robbie A

    2018-02-01

    Contact networks are fundamental to the transmission of infection and host sex often affects the acquisition and progression of infection. However, the epidemiological impacts of sex-related variation in animal contact networks have rarely been investigated. We test the hypothesis that sex-biases in infection are related to variation in multilayer contact networks structured by sex in a population of European badgers Meles meles naturally infected with Mycobacterium bovis. Our key results are that male-male and between-sex networks are structured at broader spatial scales than female-female networks and that in male-male and between-sex contact networks, but not female-female networks, there is a significant relationship between infection and contacts with individuals in other groups. These sex differences in social behaviour may underpin male-biased acquisition of infection and may result in males being responsible for more between-group transmission. This highlights the importance of sex-related variation in host behaviour when managing animal diseases. © 2017 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

  9. Criminalization, legalization or decriminalization of sex work: what female sex workers say in San Francisco, USA.

    Science.gov (United States)

    Lutnick, Alexandra; Cohan, Deborah

    2009-11-01

    Sex work is a criminal offence in San Francisco, USA, and sex work advocates have so far unsuccessfully campaigned for decriminalizing it. Some groups argue that the decriminalization movement does not represent the voices of marginalized sex workers. Using qualitative and quantitative data from the Sex Worker Environmental Assessment Team Study, we investigated the perspectives and experiences of a range of female sex workers regarding the legal status of sex work and the impact of criminal law on their work experiences. Forty women were enrolled in the qualitative phase in 2004 and 247 women in the quantitative phase in 2006-07. Overall, the women in this study seemed to prefer a hybrid of legalization and decriminalization. The majority voiced a preference for removing statutes that criminalize sex work in order to facilitate a social and political environment where they had legal rights and could seek help when they were victims of violence. Advocacy groups need to explore the compromises sex workers are willing to make to ensure safe working conditions and the same legal protections afforded to other workers, and with those who are most marginalized to better understand their immediate needs and how these can be met through decriminalization.

  10. Cancer risk in opposite-sex and same-sex twins

    DEFF Research Database (Denmark)

    Juel Ahrenfeldt, Linda

    2015-01-01

    Twin pregnancies are characterized by simultaneous development of two fetuses that share the womb. An interest in opposite-sex (OS) twins, twin pairs consisting of one male and one female, comes from animal studies that showed that exposure to sex hormones is influenced by the position of the fetus...

  11. Altering the sex determination pathway in Drosophila fat body modifies sex-specific stress responses.

    Science.gov (United States)

    Argue, Kathryn J; Neckameyer, Wendi S

    2014-07-01

    The stress response in Drosophila melanogaster reveals sex differences in behavior, similar to what has been observed in mammals. However, unlike mammals, the sex determination pathway in Drosophila is well established, making this an ideal system to identify factors involved in the modulation of sex-specific responses to stress. In this study, we show that the Drosophila fat body, which has been shown to be important for energy homeostasis and sex determination, is a dynamic tissue that is altered in response to stress in a sex and time-dependent manner. We manipulated the sex determination pathway in the fat body via targeted expression of transformer and transformer-2 and analyzed these animals for changes in their response to stress. In the majority of cases, manipulation of transformer or transformer-2 was able to change the physiological output in response to starvation and oxidative stress to that of the opposite sex. Our data also uncover the possibility of additional downstream targets for transformer and transformer-2 that are separate from the sex determination pathway and can influence behavioral and physiological responses. Copyright © 2014 the American Physiological Society.

  12. Stigma and sex work from the perspective of female sex workers in Hong Kong.

    Science.gov (United States)

    Wong, William C W; Holroyd, Eleanor; Bingham, Amie

    2011-01-01

    While the stigma surrounding sex work is both well documented and easily recognised, few studies examine stigma in this context from the perspective of the sex workers themselves. In this article we report on a study using a modified grounded theory approach to analyse a series of semi-structured interviews with 49 female sex workers in Hong Kong, in order to examine the ways in which this group experiences and negotiates the stigma which arises from their employment in the sex industry. Sex workers in Hong Kong were subject to various stigmatising forces in their daily lives in their interactions with the public, the police and their families. These processes could have a negative impact on the sex workers' health, both through obvious manifestations such as physical or verbal abuse and through more subtle processes such as those which generated or perpetuated vulnerability and those which compelled the sex workers to conceal their identities and withdraw themselves from social networks. These findings are situated in the context of broader research surrounding sex work, drawing attention to the consequences of stigma on health and their interaction with health-service providers, before briefly discussing possible means of overcoming stigma-related barriers to providing adequate healthcare for this marginalised group. © 2010 The Authors. Sociology of Health & Illness © 2010 Foundation for the Sociology of Health & Illness/Blackwell Publishing Ltd.

  13. "Bareback" pornography consumption and safe-sex intentions of men having sex with men

    NARCIS (Netherlands)

    Jonas, K.J.; Hawk, S.T.; Vastenburg, D.; de Groot, P.

    2014-01-01

    Men having sex with men (MSM) commonly consume "bareback" pornography, which includes scenes of unprotected anal intercourse. Prior research on human imitative behavior suggests that these media might counteract efforts to promote safe-sex behaviors. To date, no studies have demonstrated a causal

  14. Sex Bias in Evaluations: Effects of Ambiguity, Job Sex-Type, and Rater Gender.

    Science.gov (United States)

    Gerdes, Eugenia Proctor; Husted, Victoria L.

    Although partially caused by sex differences in aspirations and qualifications, the underrepresentation of women in professional and managerial positions also reflects the persistence of sex discrimination at the entry level. Discrimination against women applying for traditionally male jobs seems to increase with ambiguity about the fit between…

  15. Early Sex Work Initiation and Violence against Female Sex Workers in Mombasa, Kenya.

    Science.gov (United States)

    Parcesepe, Angela M; L'Engle, Kelly L; Martin, Sandra L; Green, Sherri; Suchindran, Chirayath; Mwarogo, Peter

    2016-12-01

    Between 20 and 40 % of female sex workers (FSWs) began sex work before age 18. Little is known concerning whether early initiation of sex work impacts later experiences in adulthood, including violence victimization. This paper examines the relationship between early initiation of sex work and violence victimization during adulthood. The sample included 816 FSWs in Mombasa, Kenya, recruited from HIV prevention drop-in centers who were 18 years or older and moderate-risk drinkers. Early initiation was defined as beginning sex work at 17 or younger. Logistic regression modeled recent violence as a function of early initiation, adjusting for drop-in center, age, education, HIV status, supporting others, and childhood abuse. Twenty percent of the sample reported early initiation of sex work. Although both early initiators and other FSWs reported commonly experiencing recent violence, early initiators were significantly more likely to experience recent physical and sexual violence and verbal abuse from paying partners. Early initiation was not associated with physical or sexual violence from non-paying partners. Many FSWs begin sex work before age 18. Effective interventions focused on preventing this are needed. In addition, interventions are needed to prevent violence against all FSWs, in particular, those who initiated sex work during childhood or adolescence.

  16. Where Do Chinese Adolescents Obtain Knowledge of Sex? Implications for Sex Education in China

    Science.gov (United States)

    Zhang, Liying; Li, Xiaoming; Shah, Iqbal H.

    2007-01-01

    Purpose: Sex education in China has been promoted for many years, but limited data are available regarding the sources from which adolescents receive sex-related knowledge. The present study was designed to examine the sources from which Chinese adolescents obtain their information on puberty, sexuality and STI/HIV/AIDS, and whether there are any…

  17. Sexing a sex-role-reversed species based on plumage: potential challenges in the red phalarope

    Directory of Open Access Journals (Sweden)

    Marie-Andrée Giroux

    2016-05-01

    Full Text Available Sex-role reversal, in which males care for offspring, can occur when mate competition is stronger between females than males. Secondary sex traits and mate attracting displays in sex-role-reversed species are usually more pronounced in females than in males. The red phalarope (Phalaropus fulicarius is a textbook example of a sex-role-reversed species. It is generally agreed that males are responsible for all incubation and parental care duties, whereas females typically desert males after having completed a clutch and may pair with new males to lay additional clutches. The breeding plumage of female red phalaropes is usually more brightly colored than male plumage, a reversed sexual dichromatism usually associated with sex-role reversal. Here, we confirm with PCR-based sexing that male red phalaropes can exhibit both the red body plumage typical of a female and the incubation behavior typical of a male. Our result, combined with previous observations of brightly colored red phalaropes incubating nests at the same arctic location (Igloolik Island, Nunavut, Canada, suggests that plumage dichromatism alone may not be sufficient to distinguish males from females in this breeding population of red phalaropes. This stresses the need for more systematic genetic sexing combined with standardized description of intersexual differences in red phalarope plumages. Determining whether such female-like plumage on males is a result of phenotypic plasticity or genetic variation could contribute to further understanding sex-role reversal strategies in the short Arctic summer.

  18. Counselors' Attitudes toward Domestic Violence in Same-Sex versus Opposite-Sex Relationships

    Science.gov (United States)

    Banks, Jamye R.; Fedewa, Alicia L.

    2012-01-01

    Domestic violence is often perceived to occur only in heterosexual relationships. However, domestic violence is also prevalent in same-sex relationships. The majority of the research indicates that counselors perceive same-sex domestic violence differently than heterosexual domestic violence. This literature review synthesizes the research…

  19. Sex workers, unite! (Litigating for sex workers' freedom of association in Russia).

    Science.gov (United States)

    Arps, F S E Freddie; Golichenko, Mikhail

    2014-12-11

    The existing legal framework in Russia makes sex work and related activities punishable offenses, leaving sex workers stigmatized, vulnerable to violence, and disproportionally affected by HIV and other sexually transmitted infections. In 2013, the Ministry of Justice, supported by the courts, refused registration and official recognition to the first all-Russia association of sex workers, referring to the fact that sex work is under administrative and criminal punitive bans and therefore the right of association for sex workers is unjustified. In light of international human rights standards, in particular the jurisprudence of the European Court of Human Rights, we examine in this paper whether the overall punitive legal ban on sex work in Russia is discriminatory. The government's positive obligations concerning discrimination against sex workers whose activities are consensual and between adults, and whose working conditions leave them among society's most vulnerable, should outweigh their punitive laws and policies around sex work. The scope of legal criminalization is narrow: it should apply only in exceptional cases where it is clearly justified. Copyright © 2014 Arps and Golichenko. This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original author and source are credited.

  20. Sex Differences in the Pharmacokinetics of Antidepressants : Influence of Female Sex Hormones and Oral Contraceptives

    NARCIS (Netherlands)

    Damoiseaux, Valerie A.; Proost, Johannes H.; Jiawan, Vincent C. R.; Melgert, Barbro N.

    Women are twice as likely to develop depression as men. Moreover, the symptoms they experience also show sex differences: women tend to develop depression at an earlier age and show more severe symptoms than men. Likewise, the response to antidepressant pharmacotherapy appears to have sex

  1. Sex differences in the processing of flankers.

    Science.gov (United States)

    Stoet, Gijsbert

    2010-04-01

    The study of sex differences in cognition has often focused on differences in spatial processing. Recently, sex differences in selective attention have been observed by Bayliss, di Pellegrino, and Tipper (2005), showing that women are more influenced than men by irrelevant spatial cues. The current study elaborates on this finding and tests whether sex differences in the processing of irrelevant information also occur in a simpler task, in which there is no need to redirect visual attention and no need to remember multiple spatial stimulus-response associations. Here, attention is studied using a novel combination of a go/no-go task and a flanker task. A total of 80 neurotypical participants were studied, and it was found that responses in women were more strongly affected by flanker information than were responses in men. This suggests that these sex differences were not due to difficulties with spatial reorientation, or remembering spatial stimulus-response relationships. The findings are discussed in the context of the hunter-gatherer theory of sex differences.

  2. Sex-related differences in foot shape.

    Science.gov (United States)

    Krauss, I; Grau, S; Mauch, M; Maiwald, C; Horstmann, T

    2008-11-01

    The purpose of the study was to investigate sex-related differences in foot morphology. In total, 847 subjects were scanned using a 3-D-footscanner. Three different analysis methods were used: (1) comparisons were made for absolute foot measures within 250-270 mm foot length (FL); (2) and for averaged measures (% FL) across all sizes; (3) the feet were then classified using a cluster analysis. Within 250-270 mm FL, male feet were wider and higher (mean differences (MD) 1.3-5.9 mm). No relevant sex-related differences could be found in the comparison of averaged measures (MD 0.3-0.6% FL). Foot types were categorised into voluminous, flat-pointed and slender. Shorter feet were more often voluminous, longer feet were more likely to be narrow and flat. However, the definition of 'short' and 'long' was sex-related; thus, allometry of foot measures was different. For shoe design, measures should be derived for each size and sex separately. Different foot types should be considered to account for the variety in foot shape. Improper footwear can cause foot pain and deformity. Therefore, knowledge of sex-related differences in foot measures is important to assist proper shoe fit in both men and women. The present study supplements the field of knowledge within this context with recommendations for the manufacturing of shoes.

  3. Did Lizards Follow Unique Pathways in Sex Chromosome Evolution?

    Science.gov (United States)

    Gleeson, Dianne; Georges, Arthur

    2018-01-01

    Reptiles show remarkable diversity in modes of reproduction and sex determination, including high variation in the morphology of sex chromosomes, ranging from homomorphic to highly heteromorphic. Additionally, the co-existence of genotypic sex determination (GSD) and temperature-dependent sex determination (TSD) within and among sister clades makes this group an attractive model to study and understand the evolution of sex chromosomes. This is particularly so with Lizards (Order Squamata) which, among reptiles, show extraordinary morphological diversity. They also show no particular pattern of sex chromosome degeneration of the kind observed in mammals, birds and or even in snakes. We therefore speculate that sex determination sensu sex chromosome evolution is labile and rapid and largely follows independent trajectories within lizards. Here, we review the current knowledge on the evolution of sex chromosomes in lizards and discuss how sex chromosome evolution within that group differs from other amniote taxa, facilitating unique evolutionary pathways. PMID:29751579

  4. Effects of Sex Steroids in the Human Brain.

    Science.gov (United States)

    Nguyen, Tuong-Vi; Ducharme, Simon; Karama, Sherif

    2017-11-01

    Sex steroids are thought to play a critical developmental role in shaping both cortical and subcortical structures in the human brain. Periods of profound changes in sex steroids invariably coincide with the onset of sex differences in mental health vulnerability, highlighting the importance of sex steroids in determining sexual differentiation of the brain. Yet, most of the evidence for the central effects of sex steroids relies on non-human studies, as several challenges have limited our understanding of these effects in humans: the lack of systematic assessment of the human sex steroid metabolome, the different developmental trajectories of specific sex steroids, the impact of genetic variation and epigenetic changes, and the plethora of interactions between sex steroids, sex chromosomes, neurotransmitters, and other hormonal systems. Here we review how multimodal strategies may be employed to bridge the gap between the basic and clinical understanding of sex steroid-related changes in the human brain.

  5. Did Lizards Follow Unique Pathways in Sex Chromosome Evolution?

    Directory of Open Access Journals (Sweden)

    Shayer Mahmood Ibney Alam

    2018-05-01

    Full Text Available Reptiles show remarkable diversity in modes of reproduction and sex determination, including high variation in the morphology of sex chromosomes, ranging from homomorphic to highly heteromorphic. Additionally, the co-existence of genotypic sex determination (GSD and temperature-dependent sex determination (TSD within and among sister clades makes this group an attractive model to study and understand the evolution of sex chromosomes. This is particularly so with Lizards (Order Squamata which, among reptiles, show extraordinary morphological diversity. They also show no particular pattern of sex chromosome degeneration of the kind observed in mammals, birds and or even in snakes. We therefore speculate that sex determination sensu sex chromosome evolution is labile and rapid and largely follows independent trajectories within lizards. Here, we review the current knowledge on the evolution of sex chromosomes in lizards and discuss how sex chromosome evolution within that group differs from other amniote taxa, facilitating unique evolutionary pathways.

  6. Sex determination using the Probabilistic Sex Diagnosis (DSP: Diagnose Sexuelle Probabiliste) tool in a virtual environment.

    Science.gov (United States)

    Chapman, Tara; Lefevre, Philippe; Semal, Patrick; Moiseev, Fedor; Sholukha, Victor; Louryan, Stéphane; Rooze, Marcel; Van Sint Jan, Serge

    2014-01-01

    The hip bone is one of the most reliable indicators of sex in the human body due to the fact it is the most dimorphic bone. Probabilistic Sex Diagnosis (DSP: Diagnose Sexuelle Probabiliste) developed by Murail et al., in 2005, is a sex determination method based on a worldwide hip bone metrical database. Sex is determined by comparing specific measurements taken from each specimen using sliding callipers and computing the probability of specimens being female or male. In forensic science it is sometimes not possible to sex a body due to corpse decay or injury. Skeletalization and dissection of a body is a laborious process and desecrates the body. There were two aims to this study. The first aim was to examine the accuracy of the DSP method in comparison with a current visual sexing method on sex determination. A further aim was to see if it was possible to virtually utilise the DSP method on both the hip bone and the pelvic girdle in order to utilise this method for forensic sciences. For the first part of the study, forty-nine dry hip bones of unknown sex were obtained from the Body Donation Programme of the Université Libre de Bruxelles (ULB). A comparison was made between DSP analysis and visual sexing on dry bone by two researchers. CT scans of bones were then analysed to obtain three-dimensional (3D) virtual models and the method of DSP was analysed virtually by importing the models into a customised software programme called lhpFusionBox which was developed at ULB. The software enables DSP distances to be measured via virtually-palpated bony landmarks. There was found to be 100% agreement of sex between the manual and virtual DSP method. The second part of the study aimed to further validate the method by analysing thirty-nine supplementary pelvic girdles of known sex blind. There was found to be a 100% accuracy rate further demonstrating that the virtual DSP method is robust. Statistically significant differences were found in the identification of sex

  7. Sex Ratio Bias Leads to the Evolution of Sex Role Reversal in Honey Locust Beetles.

    Science.gov (United States)

    Fritzsche, Karoline; Booksmythe, Isobel; Arnqvist, Göran

    2016-09-26

    The reversal of conventional sex roles was enigmatic to Darwin, who suggested that it may evolve when sex ratios are female biased [1]. Here we present direct evidence confirming Darwin's hypothesis. We investigated mating system evolution in a sex-role-reversed beetle (Megabruchidius dorsalis) using experimental evolution under manipulated sex ratios and food regimes. In female-biased populations, where reproductive competition among females was intensified, females evolved to be more attractive and the sex roles became more reversed. Interestingly, female-specific mating behavior evolved more rapidly than male-specific mating behavior. We show that sexual selection due to reproductive competition can be strong in females and can target much the same traits as in males of species with conventional mating systems. Our study highlights two central points: the role of ecology in directing sexual selection and the role that females play in mating system evolution. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Motivational influences on the safer sex behavior of agency-based male sex workers.

    Science.gov (United States)

    Smith, Michael D; Seal, David W

    2008-10-01

    Although indoor male sex workers (MSWs) have been found to engage in lower rates of HIV risk behavior with clients than street-based MSWs, few studies have examined the motivations behind such practices. We interviewed 30 MSWs working for the same escort agency regarding their safer sex practices with clients and their reasons for these. As in other research, MSWs reported little risk behavior with clients. Five motivational themes related to safer sex on the job emerged: health concerns, emotional intimacy, client attractiveness, relationships, and structural work factors. Results suggest that participants engaged in rational decision-making relative to sex with clients, facilitated by reduced economic incentive for riskier behavior and a supportive social context. MSWs desired a safe sexual work place, personal integrity, and minimal negative consequences to personal relationships. Collaborating with sex work employers to study their role in encouraging a safer workplace may be important to future research.

  9. 34 CFR 403.13 - What are the personnel requirements regarding the elimination of sex discrimination and sex...

    Science.gov (United States)

    2010-07-01

    ... elimination of sex discrimination and sex stereotyping? 403.13 Section 403.13 Education Regulations of the... Planning Responsibilities? § 403.13 What are the personnel requirements regarding the elimination of sex discrimination and sex stereotyping? (a) A State that desires to participate in the State Vocational and Applied...

  10. Criminal Profiles of Violent Juvenile Sex and Violent Juvenile Non-Sex Offenders: An Explorative Longitudinal Study

    Science.gov (United States)

    van Wijk, Anton Ph.; Mali, Bas R. F.; Bullens, Ruud A. R.; Vermeiren, Robert R.

    2007-01-01

    Few studies have longitudinally investigated the criminal profiles of violent juvenile sex and violent juvenile non-sex offenders. To make up for this lack, this study used police records of juveniles to determine the nature of the criminal profiles of violent sex offenders (n = 226) and violent non-sex offenders (n = 4,130). All offenders…

  11. CEE/CA: Report calls for decriminalization of sex work.

    Science.gov (United States)

    Betteridge, Glenn

    2006-04-01

    In December 2005, the Central and Eastern European Harm Reduction Network (CEEHRN) released a report calling for the decriminalization of sex work in the 27 countries of Central and Eastern Europe and Central Asia (CEE/CA). The report brings together a wealth of published and original information concerning sex work, laws regulating sex work, epidemiological data regarding HIV and other sexually transmitted infections (STIs), services available to sex workers, and human rights abuses faced by sex workers.

  12. A Review of Sex Determining Mechanisms in Geckos (Gekkota: Squamata)

    OpenAIRE

    Gamble, T.

    2010-01-01

    Geckos are a species-rich clade of reptiles possessing diverse sex determining mechanisms. Some species possess genetic sex determination, with both male and female heterogamety, while other species have temperature-dependent sex determination. I compiled information from the literature on the taxonomic distribution of these sex determining mechanisms in geckos. Using phylogenetic data from the literature, I reconstructed the minimum number of transitions among these sex determining mechanism...

  13. SEX-DETector: A Probabilistic Approach to Study Sex Chromosomes in Non-Model Organisms

    Science.gov (United States)

    Muyle, Aline; Käfer, Jos; Zemp, Niklaus; Mousset, Sylvain; Picard, Franck; Marais, Gabriel AB

    2016-01-01

    We propose a probabilistic framework to infer autosomal and sex-linked genes from RNA-seq data of a cross for any sex chromosome type (XY, ZW, and UV). Sex chromosomes (especially the non-recombining and repeat-dense Y, W, U, and V) are notoriously difficult to sequence. Strategies have been developed to obtain partially assembled sex chromosome sequences. Most of them remain difficult to apply to numerous non-model organisms, either because they require a reference genome, or because they are designed for evolutionarily old systems. Sequencing a cross (parents and progeny) by RNA-seq to study the segregation of alleles and infer sex-linked genes is a cost-efficient strategy, which also provides expression level estimates. However, the lack of a proper statistical framework has limited a broader application of this approach. Tests on empirical Silene data show that our method identifies 20–35% more sex-linked genes than existing pipelines, while making reliable inferences for downstream analyses. Approximately 12 individuals are needed for optimal results based on simulations. For species with an unknown sex-determination system, the method can assess the presence and type (XY vs. ZW) of sex chromosomes through a model comparison strategy. The method is particularly well optimized for sex chromosomes of young or intermediate age, which are expected in thousands of yet unstudied lineages. Any organisms, including non-model ones for which nothing is known a priori, that can be bred in the lab, are suitable for our method. SEX-DETector and its implementation in a Galaxy workflow are made freely available. PMID:27492231

  14. Correlates of paid sex among men who have sex with men in Chennai, India.

    Science.gov (United States)

    Newman, P A; Chakrapani, V; Cook, C; Shunmugam, M; Kakinami, L

    2008-11-01

    To assess correlates of paid sex among men who have sex with men (MSM) in Chennai, India. A randomised survey was conducted among 200 MSM recruited from public sex environments using time-space sampling. The association of predictors with paid sex was assessed with chi(2) tests and multiple logistic regression. Participants' mean age was 28.5 years (SD 8.7). Most (71.5%) were kothis; 60% had less than high school education and two-thirds had a monthly income less than 2000 Indian rupees. More than one-third (35.0%) reported daily/weekly harassment; 40.5% reported forced sex in the past year. The prevalence of paid sex was 59.5% (95% CI 52.7% to 66.3%). Univariate analyses indicated that paid sex was associated with kothi identity (chi(2) = 14.46; pharassment (chi(2) = 11.75; pharassment (AOR 2.34, 95% CI 1.16 to 4.72). MSM who engaged in paid sex (versus no paid sex) had a mean of 31 partners in the past month (versus 4, t = 6.17, pharassment and sexual violence against MSM who engage in paid sex, predominantly kothis, suggest that interventions should target structural factors placing these men at increased risk of HIV/sexually transmitted infections and other health-compromising conditions. The effectiveness of individual-level, knowledge-based and condom-focused preventive interventions may be constrained in the context of poverty, low education, harassment and sexual violence.

  15. Selecting sex: the effect of preferring sons.

    Science.gov (United States)

    Hesketh, Therese

    2011-11-01

    Son preference remains common in countries from East Asia through South Asia to the Middle East and North Africa. Where sex selective technology and abortion are readily available, such as in China, South Korea and India, this has led to a marked excess in male births. Worst excesses are seen in parts of rural China where there are 140 male births for every 100 female. This leads to large numbers of unmarriageable men. Concerns about the consequences centre around the propensity to aggression and violence of these men with increased levels of crime and antisocial behaviour, threatening societal stability and security. But recent studies do not support these assumptions, but rather suggest that these men are marginalised, lonely, withdrawn and prone to psychological problems. Measures to reduce sex selection should include enforcement of existing legislation on sex-selection, and public awareness campaigns about the dangers of late abortion and gender imbalance. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  16. Masturbation and Partnered Sex: Substitutes or Complements?

    Science.gov (United States)

    Regnerus, Mark; Price, Joseph; Gordon, David

    2017-10-01

    Drawing upon a large, recent probability sample of American adults ages 18-60 (7648 men and 8090 women), we explored the association between sexual frequency and masturbation, evaluating the evidence for whether masturbation compensates for unavailable sex, complements (or augments) existing paired sexual activity, or bears little association with it. We found evidence supporting a compensatory relationship between masturbation and sexual frequency for men, and a complementary one among women, but each association was both modest and contingent on how content participants were with their self-reported frequency of sex. Among men and women, both partnered status and their sexual contentment were more obvious predictors of masturbation than was recent frequency of sex. We conclude that both hypotheses as commonly evaluated suffer from failing to account for the pivotal role of subjective sexual contentment in predicting masturbation.

  17. Sex hormones and skeletal muscle weakness

    DEFF Research Database (Denmark)

    Sipilä, Sarianna; Narici, Marco; Kjaer, Michael

    2013-01-01

    Human ageing is accompanied with deterioration in endocrine functions the most notable and well characterized of which being the decrease in the production of sex hormones. Current research literature suggests that low sex hormone concentration may be among the key mechanism for sarcopenia...... and muscle weakness. Within the European large scale MYOAGE project, the role of sex hormones, estrogens and testosterone, in causing the aging-related loss of muscle mass and function was further investigated. Hormone replacement therapy (HRT) in women is shown to diminish age-associated muscle loss, loss...... properties. HRT influences gene expression in e.g. cytoskeletal and cell-matrix proteins, has a stimulating effect upon IGF-I, and a role in IL-6 and adipokine regulation. Despite low circulating steroid-hormone level, postmenopausal women have a high local concentration of steroidogenic enzymes in skeletal...

  18. The new science of cognitive sex differences.

    Science.gov (United States)

    Miller, David I; Halpern, Diane F

    2014-01-01

    Surprising new findings indicate that many conclusions about sex differences and similarities in cognitive abilities need to be reexamined. Cognitive sex differences are changing, decreasing for some tasks whereas remaining stable or increasing for other tasks. Some sex differences are detected in infancy, but the data are complex and depend on task characteristics. Diverse disciplines have revolutionized our understanding of why these differences exist. For instance, fraternal-twin studies align with earlier literature to help establish the role of prenatal androgens and large international datasets help explain how cultural factors such as economic prosperity and gender equity affect females and males differently. Understanding how biological and environmental factors interact could help maximize cognitive potential and address pressing societal issues. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Multiple stabbing in sex-related homicides.

    Science.gov (United States)

    Radojević, Nemanja; Radnić, Bojana; Petković, Stojan; Miljen, Maletin; Curović, Ivana; Cukić, Dragana; Soć, Miodrag; Savić, Slobodan

    2013-07-01

    It is possible that sexually driven homicides are the consequence of sexual deviation, but more often than not the main cause of such homicides stems from a non-paraphilic person's emotional component. It is known that homicides which involve multiple stabbing are very often the result of the assailant's highly expressed affect. This study tries to establish whether such homicides are essentially related to the sexual motives of the murderer. This paper is conducted through a retrospective autopsy study that includes 766 cases of homicides. These were reviewed and analysed according to the motive of the homicide, as well as by method, age, and gender of the victim, and the relationship between the victim and the assailant. The motives of homicides are classified as non-sexual and sexual, including homicides related to rape, jealousy, amorous affairs outside of an established relationship, deviant sexual behaviour of psychiatric patients, paraphilia, and disturbed emotional relationships between the victim and the assailant. Cases include both hetero- and homosexual relationships. Multiple stabbing occurs significantly more frequently in sex-related homicides (≥ 3 stab wounds) than in other homicide types. When the criteria for multiple stabbing are changed (≥ 4, 5, or 25 stab wounds), the percentage of sex-related homicides rises in every group in relation to the increased number of wounds. Sensitivity and specificity are represented by ROC curves for 3, 5 and 7 stab wounds. The correlation coefficients between multiple stabbing and sex-related homicides regarding gender are all near 0.9. For female victims, all homicides committed by 25 and more stab wounds were found to be sex-related. Statistically, jealousy was the most frequent motive for sex-related multiple stabbing homicides. Regardless of age, homicides involving multiple stabbings should be considered sex-related, especially when the victim is female. Copyright © 2013 Elsevier Ltd and Faculty of

  20. Sex assignment of lake sturgeon (Acipenser fluvescens) based on plasma sex hormone and vitellogenin levels

    Science.gov (United States)

    Craig, J.M.; Papoulias, D.M.; Thomas, M.V.; Annis, M.L.; Boase, J.

    2009-01-01

    This study focused on identifying the sex of lake sturgeon by measuring the sex hormones estradiol and testosterone, and the phosphoprotein vitellogenin (Vtg) in blood plasma by radioimmunoassay and enzyme-linked immunosorbent assay, respectively, and evaluating these techniques as tools in lake sturgeon population management. Surveys of the St Clair River (SCR) lake sturgeon population have characterized it as rebounding by having steady or increasing recruitment since 1997. However, researchers have not been able to effectively determine the sex for most of the sturgeon they capture because few fish caught during surveys are releasing gametes. A total of 115 fish were sampled from May through June in 2004 and 2005 from the SCR, Michigan, USA. Of these, only four females and eight males were verified (i.e. they were releasing gametes at time of capture), resulting in very few fish with which to validate blood hormone and Vtg biomarkers of sex. Fifty-six percent of the fish were assigned a sex designation based on biomarker criteria. Correspondence between actual gonadal sex and biomarker-directed classification was good for the small subset of fish for which gonadal sex was definitively determined. Moreover, application of the steroid values in a predictive sex assignment model developed for white sturgeon misclassified only the same two fish that were misclassified with the steroid and Vtg biomarkers. The experimental results suggest a sex ratio of 1 : 2.7 (F:M), however more conclusive methods are needed to confirm this ratio because so few fish were available for sex validation. Of the 43 males, 14 were within the legal slot limit, 11 were smaller than 1067 mm total length (TL), and 18 were larger than 1270 mm TL. All 15 females were larger than 1270 mm TL, and thus protected by the slot limit criteria. Considering that lake sturgeon are threatened in Michigan, an advantage to using blood plasma assays was that fish were not harmed, and sample collection was

  1. Male sex workers in Córdoba, Argentina: sociodemographic characteristics and sex work experiences

    Directory of Open Access Journals (Sweden)

    Mariño Rodrigo

    2003-01-01

    Full Text Available OBJECTIVE: To report on the sociodemographic characteristics and work experiences of 31 male sex workers (MSWs in the city of Córdoba, Argentina. METHODS: Information on each of the MSWs was collected using a questionnaire that covered his personal characteristics and his work background, self-assessed general health status, and use of health and social services. Scales were included in order to assess attitudes towards condom use, knowledge about safe sex, perceptions about the risk of getting HIV, individual self-efficacy, and locus of control. The questionnaire also asked each respondent to rank his level of agreement with interactive strategies for gaining client compliance with safe sex practices. RESULTS: In terms of their self-identity, out of the 30 MSWs who answered the question, 10 of them (33.3% self-identified as heterosexual and 9 (30% as bisexual. Alcohol and drug consumption and unsafe sexual practices were relatively low among the MSWs. Of the 31 MSWs responding, 21 of them (67.7% reported that they had been tested for HIV, but only 13 of them (41.9% said they had been vaccinated for either hepatitis A or hepatitis B. A variety of differences were found between the study's 17 street sex workers (sex workers who offer their services in public places such as streets and parks and the 14 independent sex workers (sex workers who are self-employed, advertise and manage their own business, and have an exclusive location for their commercial sex work. The street MSWs were younger and had less formal education. Independent MSWs were economically more settled, had been working longer in the sex industry, and were more comfortable about having sex with men. Independent MSWs were also more likely to report a gay sexual orientation and less likely to report using alcohol, marijuana, or other substances. CONCLUSIONS: The differences between street MSWs and independent MSWs are important since they could influence the negotiating of safer sex

  2. Sex ratio at birth in India, its relation to birth order, sex of previous children and use of indigenous medicine.

    Directory of Open Access Journals (Sweden)

    Samiksha Manchanda

    Full Text Available OBJECTIVE: Sex-ratio at birth in families with previous girls is worse than those with a boy. Our aim was to prospectively study in a large maternal and child unit sex-ratio against previous birth sex and use of traditional medicines for sex selection. MAIN OUTCOME MEASURES: Sex-ratio among mothers in families with a previous girl and in those with a previous boy, prevalence of indigenous medicine use and sex-ratio in those using medicines for sex selection. RESULTS: Overall there were 806 girls to 1000 boys. The sex-ratio was 720:1000 if there was one previous girl and 178:1000 if there were two previous girls. In second children of families with a previous boy 1017 girls were born per 1000 boys. Sex-ratio in those with one previous girl, who were taking traditional medicines for sex selection, was 928:1000. CONCLUSION: Evidence from the second children clearly shows the sex-ratio is being manipulated by human interventions. More mothers with previous girls tend to use traditional medicines for sex selection, in their subsequent pregnancies. Those taking such medication do not seem to be helped according to expectations. They seem to rely on this method and so are less likely use more definitive methods like sex selective abortions. This is the first such prospective investigation of sex ratio in second children looked at against the sex of previous children. More studies are needed to confirm the findings.

  3. Homage to Bateman: sex roles predict sex differences in sexual selection.

    Science.gov (United States)

    Fritzsche, Karoline; Arnqvis, Göran

    2013-07-01

    Classic sex role theory predicts that sexual selection should be stronger in males in taxa showing conventional sex roles and stronger in females in role reversed mating systems. To test this very central prediction and to assess the utility of different measures of sexual selection, we estimated sexual selection in both sexes in four seed beetle species with divergent sex roles using a novel experimental design. We found that sexual selection was sizeable in females and the strength of sexual selection was similar in females and males in role-reversed species. Sexual selection was overall significantly stronger in males than in females and residual selection formed a substantial component of net selection in both sexes. Furthermore, sexual selection in females was stronger in role-reversed species compared to species with conventional sex roles. Variance-based measures of sexual selection (the Bateman gradient and selection opportunities) were better predictors of sexual dimorphism in reproductive behavior and morphology across species compared to trait-based measures (selection differentials). Our results highlight the importance of using assays that incorporate components of fitness manifested after mating. We suggest that the Bateman gradient is generally the most informative measure of the strength of sexual selection in comparisons across sexes and/or species. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  4. The evolution of sex roles in birds is related to adult sex ratio.

    Science.gov (United States)

    Liker, András; Freckleton, Robert P; Székely, Tamás

    2013-01-01

    Sex-role reversal represents a formidable challenge for evolutionary biologists, since it is not clear which ecological, life-history or social factors facilitated conventional sex roles (female care and male-male competition for mates) to be reversed (male care and female-female competition). Classic theories suggested ecological or life-history predictors of role reversal, but most studies failed to support these hypotheses. Recent theory however predicts that sex-role reversal should be driven by male-biased adult sex ratio (ASR). Here we test this prediction for the first time using phylogenetic comparative analyses. Consistent with theory, both mating system and parental care are strongly related to ASR in shorebirds: conventional sex roles are exhibited by species with female-biased ASR, whereas sex-role reversal is associated with male-biased ASR. These results suggest that social environment has a strong influence on breeding systems and therefore revealing the causes of ASR variation in wild populations is essential for understanding sex role evolution.

  5. Female heterogamety in Madagascar chameleons (Squamata: Chamaeleonidae: Furcifer): differentiation of sex and neo-sex chromosomes

    Science.gov (United States)

    Rovatsos, Michail; Pokorná, Martina Johnson; Altmanová, Marie; Kratochvíl, Lukáš

    2015-01-01

    Amniotes possess variability in sex determining mechanisms, however, this diversity is still only partially known throughout the clade and sex determining systems still remain unknown even in such a popular and distinctive lineage as chameleons (Squamata: Acrodonta: Chamaeleonidae). Here, we present evidence for female heterogamety in this group. The Malagasy giant chameleon (Furcifer oustaleti) (chromosome number 2n = 22) possesses heteromorphic Z and W sex chromosomes with heterochromatic W. The panther chameleon (Furcifer pardalis) (2n = 22 in males, 21 in females), the second most popular chameleon species in the world pet trade, exhibits a rather rare Z1Z1Z2Z2/Z1Z2W system of multiple sex chromosomes, which most likely evolved from W-autosome fusion. Notably, its neo-W chromosome is partially heterochromatic and its female-specific genetic content has expanded into the previously autosomal region. Showing clear evidence for genotypic sex determination in the panther chameleon, we resolve the long-standing question of whether or not environmental sex determination exists in this species. Together with recent findings in other reptile lineages, our work demonstrates that female heterogamety is widespread among amniotes, adding another important piece to the mosaic of knowledge on sex determination in amniotes needed to understand the evolution of this important trait. PMID:26286647

  6. Correlates of unprotected sex with female sex workers among male clients in Tijuana, Mexico.

    Science.gov (United States)

    Goldenberg, Shira M; Gallardo Cruz, Manuel; Strathdee, Steffanie A; Nguyen, Lucie; Semple, Shirley J; Patterson, Thomas L

    2010-05-01

    Tijuana, situated adjacent to San Diego, CA on the US-Mexico border, is experiencing an emerging HIV epidemic, with prevalence among female sex workers (FSWs) having risen in recent years from Tijuana. In 2008, males from San Diego (N = 189) and Tijuana (N = 211) aged 18 or older who had paid or traded for sex with a FSW in Tijuana during the past 4 months were recruited in Tijuana's red light district. Participants underwent psychosocial interviews, and were tested for HIV, syphilis (Treponema pallidum), gonorrhea (Neisseria gonorrhoeae), and Chlamydia (Chlamydia trachomatis). Of 394 men, median age was 36 years, 42.1% were married, and 39.3% were unemployed. Ethnic composition was 13.2% white, 79.4% Hispanic, and 7.4% black or other. Half (50.3%) reported unprotected vaginal or anal sex with FSWs in Tijuana in the past 4 months. High proportions reported using drugs during sex (66%), and 36% reported frequenting the same FSW. Factors independently associated with unprotected sex with FSWs were using drugs during sex, visiting the same FSW, being married, and being unemployed. FSWs' clients represent a sexually transmitted infections/HIV transmission "bridge" through unprotected sex with FSWs, wives, and other partners. Tailored interventions to promote consistent condom use are needed for clients, especially within the context of drug use and ongoing relations with particular FSWs.

  7. Correlates of unprotected anal sex among men who have sex with men in Tijuana, Mexico

    Directory of Open Access Journals (Sweden)

    Barrón-Limón Sergio

    2012-06-01

    Full Text Available Abstract Background Although men who have sex with men (MSM are disproportionately affected by HIV/AIDS in Mexico, data on current risk behaviors in this population are lacking. This study investigated the prevalence and correlates of unprotected anal intercourse (UAI in a sample of 260 MSM in Tijuana, Mexico. Methods In June 2010, men attending a gay pride celebration were invited to complete a sexual risk survey. Men who reported UAI with a male partner in the past year were compared with men who reported only protected anal sex during the same period. Results Mean age of participants was 29.7; 54% had a high school diploma or less; and 43% were unemployed. In the past year, 55% had been tested for HIV, 21% reported using illicit drugs before or during sex, and 94% had sex only with men. Overall, 50% reported having UAI with another male in the past year. Factors independently associated with UAI in the past year were unemployment (AOR = 1.87, attending adult movie theaters (AOR = 2.21, using illicit drugs before or during sex (AOR = 2.43, and not having a recent HIV test (AOR = 1.85. Conclusions Interventions to promote HIV testing and condom use among men who have sex with men may want to consider venue-specific approaches, as well as focus on drug-use issues in the context of unsafe sex.

  8. Understanding the broad influence of sex hormones and sex differences in the brain.

    Science.gov (United States)

    McEwen, Bruce S; Milner, Teresa A

    2017-01-02

    Sex hormones act throughout the entire brain of both males and females via both genomic and nongenomic receptors. Sex hormones can act through many cellular and molecular processes that alter structure and function of neural systems and influence behavior as well as providing neuroprotection. Within neurons, sex hormone receptors are found in nuclei and are also located near membranes, where they are associated with presynaptic terminals, mitochondria, spine apparatus, and postsynaptic densities. Sex hormone receptors also are found in glial cells. Hormonal regulation of a variety of signaling pathways as well as direct and indirect effects on gene expression induce spine synapses, up- or downregulate and alter the distribution of neurotransmitter receptors, and regulate neuropeptide expression and cholinergic and GABAergic activity as well as calcium sequestration and oxidative stress. Many neural and behavioral functions are affected, including mood, cognitive function, blood pressure regulation, motor coordination, pain, and opioid sensitivity. Subtle sex differences exist for many of these functions that are developmentally programmed by hormones and by not yet precisely defined genetic factors, including the mitochondrial genome. These sex differences and responses to sex hormones in brain regions, which influence functions not previously regarded as subject to such differences, indicate that we are entering a new era of our ability to understand and appreciate the diversity of gender-related behaviors and brain functions. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  9. The differences between sex offenders who victimise older women and sex offenders who offend against children.

    Science.gov (United States)

    Browne, K D; Hines, Morag; Tully, Ruth J

    2018-01-01

    Within the literature on sex offending, much attention is paid to the distinction between those sex offenders who offend against adults and those who offend against children. In contrast, there is a paucity of research into sex offenders who offend specifically against elderly or older victims. A detailed interview and psychometric tests were conducted with a sample of 28 sex offenders who had been convicted of a sexually motivated offence against an older female. These data were compared to a sample of 23 child sex offenders. Results indicate that amongst other significant differences between these sub-groups, men who offend against older women are generally younger, are more violent, and are more likely to use a weapon and cause injury and death compared to child sex offenders. The men who offended against children were more likely to think about and plan their offending, spend more time with the victim pre and post offence, admit sexual arousal during the offence, and admit to a sexual motivation for the offence. This study suggests that men who sexually offend against older women and men who sexually offend against children are distinct groups. Treatment and risk management strategies should take this into account. Further exploration of this sub-group of offenders is recommended to help inform treatment and risk management strategies for sex offenders who offend against older people.

  10. Characterization of juvenile play in rats: importance of sex of self and sex of partner.

    Science.gov (United States)

    Argue, Kathryn J; McCarthy, Margaret M

    2015-01-01

    Juvenile social play is observed in many mammalian species, and its disruption in several neuropsychiatric disorders has greatly increased interest in understanding the origins and sources of variability in this behavior. We quantified social play behavior in juvenile rats and investigated the impact of sex and familiarity of the play partner. Sex differences in play behavior were investigated by comparing males and females from either same- or mixed-sex pairs with data pooled over 12 days of analysis. Whether play was altered based on the sex of the play partner was assessed using a paired analysis to compare play with a same- or opposite-sex play partner for both males and females. Additionally, a repeated measures design was utilized to determine whether play changed with increasing age. On postnatal day 33, a novel play partner was introduced. We used a repeated measures analysis to compare postnatal day 33 with the previous day. These approaches were used to assess the effects of age, sex, sex of partner, and familiarity of partner on total social play behavior as well as how play was broken down into components, such as pouncing, pinning, chasing, and boxing. There were sex differences in total frequency of play, and specific parameters of play behavior, such as chasing, pouncing, pinning, and boxing. Additionally, males significantly altered their play behavior in response to the sex of their play partner, whereas females were more sensitive to the familiarity of the play partner. This study provides critical groundwork for uncovering factors that regulate social play behavior and can be used to guide future mechanistic based work.

  11. Interactive effects of sex hormones and gender stereotypes on cognitive sex differences--a psychobiosocial approach.

    Science.gov (United States)

    Hausmann, Markus; Schoofs, Daniela; Rosenthal, Harriet E S; Jordan, Kirsten

    2009-04-01

    Biological and social factors have been shown to affect cognitive sex differences. For example, several studies have found that sex hormones have activating effects on sex-sensitive tasks. On the other hand, it has been shown that gender stereotypes can influence the cognitive performance of (gender-) stereotyped individuals. However, few studies have investigated the combined effects of both factors. The present study investigated the interaction between sex hormones and gender stereotypes within a psychobiosocial approach. One hundred and fourteen participants (59 women) performed a battery of sex-sensitive cognitive tasks, including mental rotation, verbal fluency, and perceptual speed. Saliva samples were taken immediately after cognitive testing. Levels of testosterone (T) were analysed using chemiluminescence immunoassay (LIA). To activate gender stereotypes, a questionnaire was applied to the experimental group that referred to the cognitive tasks used. The control group received an identical questionnaire but with a gender-neutral content. As expected, significant sex differences favouring males and females appeared for mental rotation and verbal fluency tasks, respectively. The results revealed no sex difference in perceptual speed. The male superiority in the Revised Vandenberg and Kuse Mental Rotations Tests (MRT-3D) was mainly driven by the stereotype-active group. No significant sex difference in MRT-3D appeared in the control group. The MRT-3D was also the task in which a strong gender-stereotype favouring males was present for both males and females. Interestingly, T levels of the stereotype-activated group were 60% higher than that of male controls. The results suggest that sex hormones mediate the effects of gender stereotypes on specific cognitive abilities.

  12. Sex chromosome repeats tip the balance towards speciation.

    Science.gov (United States)

    O'Neill, Michael J; O'Neill, Rachel J

    2018-04-06

    Because sex chromosomes, by definition, carry genes that determine sex, mutations that alter their structural and functional stability can have immediate consequences for the individual by reducing fertility, but also for a species by altering the sex ratio. Moreover, the sex-specific segregation patterns of heteromorphic sex chromosomes make them havens for selfish genetic elements that not only create sub-optimal sex ratios, but can also foster sexual antagonism. Compensatory mutations to mitigate antagonism or return sex ratios to a Fisherian optimum can create hybrid incompatibility and establish reproductive barriers leading to species divergence. The destabilizing influence of these selfish elements is often manifest within populations as copy number variants (CNVs) in satellite repeats and transposable elements (TE) or as CNVs involving sex determining genes, or genes essential to fertility and sex chromosome dosage compensation. This review catalogs several examples of well-studied sex chromosome CNVs in Drosophilids and mammals that underlie instances of meiotic drive, hybrid incompatibility and disruptions to sex differentiation and sex chromosome dosage compensation. While it is difficult to pinpoint a direct cause/effect relationship between these sex chromosome CNVs and speciation, it is easy to see how their effects in creating imbalances between the sexes, and the compensatory mutations to restore balance, can lead to lineage splitting and species formation. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  13. An Allometric Analysis of Sex and Sex Chromosome Dosage Effects on Subcortical Anatomy in Humans

    Science.gov (United States)

    Clasen, Liv; Giedd, Jay N.; Blumenthal, Jonathan; Lerch, Jason P.; Chakravarty, M. Mallar; Raznahan, Armin

    2016-01-01

    Structural neuroimaging of humans with typical and atypical sex-chromosome complements has established the marked influence of both Yand X-/Y-chromosome dosage on total brain volume (TBV) and identified potential cortical substrates for the psychiatric phenotypes associated with sex-chromosome aneuploidy (SCA). Here, in a cohort of 354 humans with varying karyotypes (XX, XY, XXX, XXY, XYY, XXYY, XXXXY), we investigate sex and SCA effects on subcortical size and shape; focusing on the striatum, pallidum and thalamus. We find large effect-size differences in the volume and shape of all three structures as a function of sex and SCA. We correct for TBV effects with a novel allometric method harnessing normative scaling rules for subcortical size and shape in humans, which we derive here for the first time. We show that all three subcortical volumes scale sublinearly with TBV among healthy humans, mirroring known relationships between subcortical volume and TBV among species. Traditional TBV correction methods assume linear scaling and can therefore invert or exaggerate sex and SCA effects on subcortical anatomy. Allometric analysis restricts sex-differences to: (1) greater pallidal volume (PV) in males, and (2) relative caudate head expansion and ventral striatum contraction in females. Allometric analysis of SCA reveals that supernumerary X- and Y-chromosomes both cause disproportionate reductions in PV, and coordinated deformations of striatopallidal shape. Our study provides a novel understanding of sex and sex-chromosome dosage effects on subcortical organization, using an allometric approach that can be generalized to other basic and clinical structural neuroimaging settings. SIGNIFICANCE STATEMENT Sex and sex-chromosome dosage (SCD) are known to modulate human brain size and cortical anatomy, but very little is known regarding their impact on subcortical structures that work with the cortex to subserve a range of behaviors in health and disease. Moreover

  14. Encoding Processes and Sex-Role Preferences

    Science.gov (United States)

    Kail, Robert V., Jr.; Levine, Laura E.

    1976-01-01

    Seven and 10-year-olds were tested on memory and sex-role preference tasks. The memory task was the Wickens release from proactive inhibition paradigm in which short-term recall of words is tested on successive trials. Children selected favorite pictures from an array including masculine and feminine items. (JH)

  15. The Multiple Choices of Sex Education

    Science.gov (United States)

    Hamilton, Rashea; Sanders, Megan; Anderman, Eric M.

    2013-01-01

    Sex education in middle and high school health classes is critically important because it frequently comprises the primary mechanism for conveying information about sexual health to adolescents. Deliver evidence-based information on HIV and pregnancy prevention practices and they will be less likely to engage in risky sexual behaviors, the theory…

  16. Undergraduates Perspectives on Sex Education and Teenage ...

    African Journals Online (AJOL)

    This study examines undergraduates' perspective on sex education and teenage pregnancy in Covenant University, Ota, Ogun State, Nigeria. The study population was 250 undergraduates of Covenant University. Frequency tables, linear regression analysis and analysis of variance were used to analyze the data collected ...

  17. Antichrist, Explicit Sex, Anxiety, and Care

    DEFF Research Database (Denmark)

    Grodal, Torben Kragh

    2015-01-01

    The article analyzes how von Trier's Antichrist uses explicit sex to discuss the relation between fear of human embodiment and a longing for care and spiritual intimacy. It discusses how lyrical episodes contrasts descriptions of embodied degradation and experiences of being imprisoned in the body....

  18. Antonio Lopez: Fashion, Art, Sex & Disco

    DEFF Research Database (Denmark)

    Langkjær, Michael Alexander

    2014-01-01

    Book review. Roger Padilha and his brother Mauricio may already be familiar to some as the New York-based fashion publicists, creators of the fashion public relations agency MAO PR, and as authors of The Stephen Sprouse Book (Rizzoli, 2009). Antonio Lopez: Fashion, Art, Sex & Disco, their second...

  19. Sex differences in mortality by ethnic background

    DEFF Research Database (Denmark)

    Oksuzyan, Anna; Drefahl, Sven; Jacobsen, Rune

    migrant effect and predominantly male migration from non-Western countries to Denmark and Sweden in 1960-70s, as well as high fertility in their female spouses, we expect to find even smaller sex differential mortality among migrants than in the ethnic Danish and Swedish populations. We use high...

  20. Sex Differences in Doctoral Student Publication Rates

    Science.gov (United States)

    Lubienski, Sarah Theule; Miller, Emily K.; Saclarides, Evthokia Stephanie

    2018-01-01

    Women in the sciences who earn PhDs are less likely than their male counterparts to pursue tenure-track positions at research universities. Moreover, among those who become STEM researchers, men have been found to publish more than women. These patterns raise questions about when sex differences in publication begin. Using data from a survey of…

  1. Maternal preconception diet and the sex ratio

    NARCIS (Netherlands)

    Cramer, J.S.; Lumey, L.H.

    2009-01-01

    Temporal variations in the sex ratio or the ratio of boys over girls at birth have been widely studied and variously attributed to social changes, conditions of war, and environmental changes. Recently, Mathews, Johnson and Neil (2008) studied the direct evidence of individual pregnancies and

  2. Sex determination: ciliates' self-censorship.

    Science.gov (United States)

    Bloomfield, Gareth

    2014-07-07

    Differentiation involves the expression of certain latent cellular characteristics and the repression of others. A new study has revealed how Paramecium uses short RNAs to delete information from the somatic genome of one of its two sexes. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Single-Sex Schooling Gets New Showcase

    Science.gov (United States)

    McNeil, Michele

    2008-01-01

    Single-sex classrooms and schools are common in private education and have emerged as popular options in urban public school districts, such as New York City, particularly as a strategy for raising the achievement of African-American boys. South Carolina is at the forefront of implementing such programs statewide. Ninety-seven schools in South…

  4. Theorising Practice in Single-Sex Work.

    Science.gov (United States)

    Tett, Lyn

    1996-01-01

    The practice of adult educators in single-sex settings is directed by "theories-in-use" about the social construction of gender, such as gender is culturally constructed but people internalize gender stereotypes; gender stereotypes can be challenged and changed; and power to define gender roles lies in patriarchy, but it can be contested…

  5. Fast, reliable sexing of prosimian DNA

    DEFF Research Database (Denmark)

    Fredsted, Tina; Villesen, Palle

    2004-01-01

    to identify conserved regions in the amelogenin gene. Using these conserved regions, we can target species that have no sequence information. We designed a single, conserved primer pair that is useful for fast and reliable molecular sexing of prosimian primates. A single PCR yields two fragments in males...

  6. Daily practices of health among sex workers

    Directory of Open Access Journals (Sweden)

    Elouyse Fernandes Leitão

    2012-09-01

    Full Text Available Objective: To describe the health practices adopted by sex workers in their daily lives. Methods: A qualitative study that took place at bars where sex workers of Maceió –AL, Brazil, work. The universe of participant subjects was integrated by 15 female sex workers, aged between 20 and 39 years, assisted by the team of a Street Clinic. The research took place between August and October 2011 and women were randomly selected. Data was collected through semi-structured interviews, which were all audio-recorded and transcribed for further analysis and interpretation. Results: Thematic analysis of the data produced and the theoretical framework of health promotion enabled the categorization of the health practices in daily life of these women, such as: prevention of sexually transmitted diseases, body care and aesthetics, physical activity, nutrition, leisure, interpersonal relationships, consumption of alcohol and others drugs, self-medication, and quest for health services. The ways they appropriate themselves of such practices are conditioned by the social vulnerability and economic and sociocultural context they are in. Conclusion: Despite the deficiencies found in the development of these practices, sex workers seek to preserve habits that improve their physical, social and mental health, as well as the pursuit of professional care and services to promote their health.

  7. The Media, Marketing, and Single Sex Schooling

    Science.gov (United States)

    Mills, Martin

    2004-01-01

    The Australian media's interest in education, as in many Anglophone countries, is frequently dominated by concerns about boys in schools. In 2002, in a country region of the Australian State of Queensland, this concern was evident in a debate on the merits of single sex schooling that took place in a small local newspaper. The debate was fuelled…

  8. Attitude toward Christianity and premarital sex.

    Science.gov (United States)

    Francis, Leslie J

    2006-02-01

    A Pearson correlation of .55 was found for a sample of 243 female undergraduates in Wales (M age=20.9 yr., SD=4.6) between high scores on the Francis Scale of Attitude toward Christianity and rejection of premarital sex.

  9. Moral development of solo juvenile sex offenders

    NARCIS (Netherlands)

    van Vugt, E.; Stams, G.J.; Dekovic, M.; Brugman, D.; Rutten, E.; Hendriks, J.

    2008-01-01

    This study compared the moral development of solo juvenile male sex offenders (n = 20) and juvenile male non-offenders (n = 76), aged 13-19 years, from lower socioeconomic and educational backgrounds. The Moral Orientation Measure (MOM) was used to assess punishment- and victim-based moral

  10. Sex-Reassignment Rules in Shiite Jurisprudence.

    Science.gov (United States)

    Kalbasi-Isfahani, Fahimeh; Deleer, Mohsen

    2016-01-01

    The "Sex-Reassignment Surgery" is a solution that besides behavioral therapy has been suggested to people suffering from gender identity disorders in recent years. In Iran, this trend has become more popular over the past years due to the inclination to reach to the goal rapidly with less effort and also the surgery has attracted many patients with the problem. Religious clerics have tried to determine the religious doctrines for this practice and as a result a group of them favor an absolute permission while others choose prohibition and some of them favor a middle path. The aim of this study was to determine the religious doctrines for Sex-Reassignment and legitimate treatment for GID. The research method was a library research based on which an investigation was done by analyzing the relevant books, articles and dissertations. Primary documents of Islamic sources (Quran and tradition) along with scientific, medical and psychological materials were used in this research. In this study, the survey shows that none of the reasons have the power to deliver a definitive and religious ruling on this issue because the validity of its reasons is related to the reality of "Sex-Reassignment". The results demonstrate that Sex-Reassignment is prohibited and it is not authorized. In case of urgency for doing the surgery, the gender of the person should not be changed.

  11. Jealousy, Gender, Sex Roles, and Dependency.

    Science.gov (United States)

    Madden, Margaret E.; And Others

    One hundred adults ages 18 to 42 completed measures of jealousy and dependency in romantic relationships and of sex role traditionalism. Traditionalism and jealousy were correlated, as predicted, but dependency and jealousy were not. For men, but not for women, traditionalism and jealousy were positively correlated. Dependency and traditionalism…

  12. It Isn't Sex Education unless...

    Science.gov (United States)

    Hacker, Sylvia S.

    1981-01-01

    An effective sex education curriculum deals with both feelings and behaviors. It must address decision making and problem solving in regard to relationship formation, readiness for intercourse, use of contraception, child rearing, and social responsibility and should be incorporated into education throughout the educational process. (JN)

  13. Sex Differences in College Student Drug Use

    Science.gov (United States)

    Strimbu, Jerry L.; And Others

    1973-01-01

    Determines patterns of drug usage and related behavior of college, university, and junior college students on a state-wide basis. This article focuses on sex as it relates to the total pattern of drug abuse of nine specific substances among a large group of college students and examines results in terms of both practical and statistical…

  14. Empowerment through Sex Education? Rethinking Paradoxical Policies

    Science.gov (United States)

    Naezer, Marijke; Rommes, Els; Jansen, Willy

    2017-01-01

    Youth empowerment is the main goal of sex education according to Dutch Government and NGO policies. Academics from different disciplines have argued, however, that the ideal of empowerment through education is problematic, because of the unequal power relations implicated in educational practices. Building on one-and-a-half years of online and…

  15. Sex differences in consequences of musculoskeletal pain

    NARCIS (Netherlands)

    Wijnhoven, H. A H; de Vet, Henrica C W; Picavet, H. Susan J

    STUDY DESIGN. Cross-sectional population-based study. OBJECTIVE. To study sex differences in consequences of musculoskeletal pain (MP): limited functioning, work leave or disability, and healthcare use. SUMMARY OF BACKGROUND DATA. MP is a major public health problem in developed countries due to

  16. Mexican Women, Migration and Sex Roles.

    Science.gov (United States)

    Baca, Reynaldo; Dexter, Bryan

    1985-01-01

    Compares Mexican women involved in migration to understand how their sex roles and status have been affected. Uses data from two separate studies: ethnography on migrants' wives left at home in a Mexican village and a survey of unauthorized immigrants in the Los Angeles area. (SA)

  17. Psychoeducational Implications of Sex Chromosome Anomalies

    Science.gov (United States)

    Wodrich, David L.; Tarbox, Jennifer

    2008-01-01

    Numerous anomalies involving the sex chromosomes (X or Y) have been documented and their impact on development, learning, and behavior studied. This article reviews three of these disorders, Turner syndrome, Klinefelter syndrome, and Lesch-Nyhan disease. Each of these three is associated with one or more selective impairments or behavioral…

  18. Sex Work Research: Methodological and Ethical Challenges

    Science.gov (United States)

    Shaver, Frances M.

    2005-01-01

    The challenges involved in the design of ethical, nonexploitative research projects with sex workers or any other marginalized population are significant. First, the size and boundaries of the population are unknown, making it extremely difficult to get a representative sample. Second, because membership in hidden populations often involves…

  19. Sex Work and Students: An Exploratory Study

    Science.gov (United States)

    Roberts, Ron; Bergstrom, Sandra; La Rooy, David

    2007-01-01

    Available evidence suggests that changes in the funding of higher education have led to some students entering the sex industry in order to make ends meet. The current study comprises a sample of undergraduates (N=130) in the south of England, who completed a cross-sectional survey of their financial circumstances, health, psychological…

  20. Teaching Sex, Gender, Transsexual, and Transgender Concepts

    Science.gov (United States)

    McGrath, Karen

    2014-01-01

    As many gender teachers know, distinctions between and among complex terms in the lesbian, gay, bisexual, trans (gender or sexual), queer (LGBTQ) group are often difficult for students to articulate and identify. In fact, terms like "sex" and "gender" are often conflated in public discourse, and terms like…

  1. Masculinity, sex and survival in Zambian prisons

    DEFF Research Database (Denmark)

    Ryberg, Anne Egelund

    2014-01-01

    Sexual relations between men in prisons occur all over the world, also in African prisons. Sex between men is considered deviant in Zambian society, yet for some prisoners it is a way to cope with the stress of incarceration. Prisoners have to cope with extreme challenges in terms of insufficient...

  2. Sex Education as a Transversal Subject

    Science.gov (United States)

    Rabelo, Amanda Oliveira; Pereira, Graziela Raupp; Reis, Maria Amélia; Ferreira, António G.

    2015-01-01

    Currently, sex education is in many countries a transversal subject, in which the school becomes a privileged place for the implementation of policies that aim at promoting "public health." Its design as a cross-cutting subject envisages fostering the dissemination of these subjects in all pedagogical and curricular fields; however, we…

  3. Monozygotic twins of different apparent sex

    Energy Technology Data Exchange (ETDEWEB)

    Yokota, Yukifumi; Fujino, Nobuyuki; Sato, Yoshiaki; Matsunobu, Akira; Tadokoro, Mamoru [Sagamihara Kyodo Hospital (Japan); Akane, Atsushi [Kansai Medical College, Osaka (Japan); Matsuura, Nobuo; Maeda, Tohru [Kitasato Univ. (Japan); Nakahori, Yutaka; Nakagome, Yasuo [Univ. of Tokyo (Japan)

    1994-10-15

    We report on twins of unlike sex who shared a 45,X/46,X, +mar karyotype. The mar chromosome was found to be Yq- by DNA analysis. Marker studies, including 8 VNTR loci, yielded a probability of monozygosity of 0.99999996. 16 refs., 1 fig., 1 tab.

  4. A Study of Sex Roles and Reticence.

    Science.gov (United States)

    Copeland, Gary A.; Kelly, Lynne

    Defining communication reticence as anxiousness due to a lack of basic communication skills, a study was conducted to determine (1) whether significant differences exist in the distribution of sex roles between reticent and nonreticent populations, (2) whether reticents and nonreticents differ in masculinity and femininity, and (3) which qualities…

  5. Appraising the Vatican's Approach to Sex Education.

    Science.gov (United States)

    Thomas, David M.

    1984-01-01

    Analyzes the Vatican publication, "Educational Guidance in Human Love," which underscores the responsibilities of family and church in sex education. Affirms the positive aspects of the report and points to its weaknesses and omissions. Suggests possible responses to the document by parishes and schools. (DMM)

  6. A Feminist Revision of Contemporary Sex Therapy.

    Science.gov (United States)

    Keystone, Marianne; Carolan, Marsha T.

    1998-01-01

    The tenets of traditional sex therapy based on dysfunction and pathology are critiqued, and a feminist model proposed. Recognizing that equity and power issues, particularly in heterosexual relationships, are basic issues, women and issues of gender are at the center of the model. Three cases illustrate the model. (Author/EMK)

  7. Primate Innovation: Sex, Age and Social Rank

    NARCIS (Netherlands)

    Reader, S.M.; Laland, K.N.

    2001-01-01

    Analysis of an exhaustive survey of primate behavior collated from the published literature revealed significant variation in rates of innovation among individuals of different sex, age and social rank. We searched approximately 1,000 articles in four primatology journals, together with other

  8. Sex determination of baleen whale artefacts

    DEFF Research Database (Denmark)

    Sinding, Mikkel Holger Strander; Tervo, Outi M.; Grønnow, Bjarne

    2016-01-01

    to 4500 years old bowhead whale samples, and for comparison on dilution series from modern bowhead whales of known sex. DNA sequencing of PCR products obtained from the ancient material confirmed a higher proportion of successful PCR amplifications of the X homologue over the Y homologue. This potentially...

  9. Michael Hauskeller: Sex and the Posthuman Condition

    NARCIS (Netherlands)

    Miller, Lantz Eugene

    2016-01-01

    This new book from Michael Hauskeller explores the currently marketed or projected sex/love products that exhibit some trait of so-called “posthumanistic” theory or design. These products are so designated because of their intention to fuse high technologies, including robotics and computing, with

  10. Exploring Sex Roles in African Studies.

    Science.gov (United States)

    Lee, David R.

    A method for incorporating an examination of sex roles and position of women into an undergraduate course on geography of Africa is discussed. It is a regional geography course with a cultural emphasis. Five percent of the total instruction is devoted to the examination of women. This is justified because geographical concepts such as spatial…

  11. Sex Discrimination as to Maternity Benefits

    Science.gov (United States)

    Larson, Arthur

    1975-01-01

    A general survey of the state of the law at all points where maternity produces a claim of sex discrimination in employment and discussion of whether, under Geduldig v. Aiello, all private fringe benefit systems must equate normal pregnancy with temporary sickness and disability. (JT)

  12. Comprehensive Sex Education: Research and Results

    Science.gov (United States)

    Advocates for Youth, 2009

    2009-01-01

    Since 1997 the federal government has invested more than $1.5 billion dollars in abstinence-only programs--proven ineffective programs which censor or exclude important information that could help young people protect their health. In fact, until recently, programs which met a strict abstinence-only definition were the only type of sex education…

  13. Unprotected sex, sexually transmitted infections and problem ...

    African Journals Online (AJOL)

    Administrator

    Background: A description of the pattern of use of alcohol and other substances among female sex workers (FSWs) is particularly important .... Never married. 2,375 (95.5). Married. 9 (0.4). Separated/divorced/widowed. 83 (3.3). Religion. Orthodox Christian. 2,148 (86.4). Catholic. 60 (2.4). Protestant. 55 (2.2). Muslim.

  14. The Satisfaction with Sex Life Scale

    Science.gov (United States)

    Neto, Felix

    2012-01-01

    The purpose of this article was to develop the Satisfaction With Sex Life Scale (SWSLS). Scores from the SWSLS have favorable psychometric properties. Cronbach's alpha was 0.92. Evidence based on relations to other variables was examined. Suggestions concerning the use of the SWSLS for research and clinical purposes are offered. (Contains 2…

  15. What To Tell the Kids about Sex.

    Science.gov (United States)

    Hymowitz, Kay S.

    2003-01-01

    Discusses the history of the controversy over comprehensive sex education versus abstinence education, focusing on the politics of the issue; support for abstinence education; how abstinence programs appeal to students' emotions; the influence of character education on abstinence education; how abstinence education can change students' decisions…

  16. Maternal preconception diet and the sex ratio

    NARCIS (Netherlands)

    Cramer, J.S.; Lumey, L.H.

    2010-01-01

    Temporal variations in the sex ratio, or the ratio of boys to girls at birth, have been widely studied and variously attributed to social changes, conditions of war, and environmental changes. Recently, Mathews et al. ["You are what your mother eats: Evidence for maternal preconception diet

  17. Young Men, Masculinities and Sex Education

    Science.gov (United States)

    Limmer, Mark

    2010-01-01

    This paper draws on focus group and interview data from 45 young men from the north of England to explore the barriers to effective sex and relationships education (SRE). Recent policy debates in relation to establishing statutory SRE in schools provide an opportunity to revisit how it is currently delivered to, and received by, young men. The…

  18. Sex Segregation in Undergraduate Engineering Majors

    Science.gov (United States)

    Litzler, Elizabeth

    2010-01-01

    Gender inequality in engineering persists in spite of women reaching parity in college enrollments and degrees granted. To date, no analyses of educational sex segregation have comprehensively examined segregation within one discipline. To move beyond traditional methods of studying the long-standing stratification by field of study in higher…

  19. Infection among Commercial Sex Workers in Jos

    African Journals Online (AJOL)

    A study of HHV8 seropositivity was conducted among commercial sex workers in Jos aimed at determining the prevalence in relation to history of STD, duration of prostitution, age and number of sexual partners per day. Antibodies to HHV8 were detected by enzyme linked - immunosorbent assay (ELISA) (Advanced ...

  20. Sex Determination from Fingerprint Ridge Density | Gungadin ...

    African Journals Online (AJOL)

    This study was conducted with an aim to establish a relationship between sex and fingerprint ridge density. The fingerprints were taken from 500 subjects (250 males and 250 females) in the age group of 18-60 years. After taking fingerprints, the ridges were counted in the upper portion of the radial border of each print for all ...