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Sample records for additional sex comb-like

  1. Biased diffusion in three-dimensional comb-like structures

    PubMed Central

    Berezhkovskii, Alexander M.; Dagdug, Leonardo; Bezrukov, Sergey M.

    2015-01-01

    In this paper, we study biased diffusion of point Brownian particles in a three-dimensional comb-like structure formed by a main cylindrical tube with identical periodic cylindrical dead ends. It is assumed that the dead ends are thin cylinders whose radius is much smaller than both the radius of the main tube and the distance between neighboring dead ends. It is also assumed that in the main tube, the particle, in addition to its regular diffusion, moves with a uniform constant drift velocity. For such a system, we develop a formalism that allows us to derive analytical expressions for the Laplace transforms of the first two moments of the particle displacement along the main tube axis. Inverting these Laplace transforms numerically, one can find the time dependences of the two moments for arbitrary values of both the drift velocity and the dead-end length, including the limiting case of infinitely long dead ends, where the unbiased diffusion becomes anomalous at sufficiently long times. The expressions for the Laplace transforms are used to find the effective drift velocity and diffusivity of the particle as functions of its drift velocity in the main tube and the tube geometric parameters. As might be expected from common-sense arguments, the effective drift velocity monotonically decreases from the initial drift velocity to zero as the dead-end length increases from zero to infinity. The effective diffusivity is a more complex, non-monotonic function of the dead-end length. As this length increases from zero to infinity, the effective diffusivity first decreases, reaches a minimum, and then increases approaching a plateau value which is proportional to the square of the particle drift velocity in the main tube. PMID:25854222

  2. Bottlebrush and comb-like elastomers as ultra-soft electrical and acoustically active materials

    NASA Astrophysics Data System (ADS)

    Daniel, William; Vatankhah-Varnosfaderani, Mohammad; Pandya, Ashish; Burdynska, Joanna; Morgan, Benjamin; Everhart, Matthew; Matyjaszewski, Krzysztof; Dobrynin, Andrey; Rubinstein, Michael; Sheiko, Sergei; UNC MIRT Team

    Without swelling in a solvent, it is challenging to obtain materials with a modulus below 105 Pa, which is dictated by chain entanglements. We show that macromolecules can be disentangled by dense grafting of side chains to long polymer chains. The bottlebrush and comb-like architectures demonstrate a unique combination of flexibility and network dilution, leading to significant decrease of the entanglement modulus (Ge) and increase of extensibility. Following theoretical predictions, it has been shown that the Ge is controlled by the polymerization degrees of sidechains (nsc) and grafting spacer (ng) as Ge ~ (ng /nsc) 1 . 5 . Using the reduced entanglement density, we developed solvent-free elastomers with moduli on the order of 100 Pa and excellent extensibility. Using bottlebrush architectures we have developed PDMS dielectric actuators with high deformation at low electric field strength. Additionally strong acoustic adsorption leads to materials showing shape and volume control in light opaque environments. NSF (DMR 1409710, DMR 1122483, DMR 1407645, and DMR 1436201).

  3. Preparation and Photoluminescence of ZnO Comb-Like Structure and Nanorod Arrays

    NASA Astrophysics Data System (ADS)

    Yin, Song; Chen, Yi-qing; Su, Yong; Zhou, Qing-tao

    2007-06-01

    A large quantity of Zinc oxide (ZnO) comb-like structure and high-density well-aligned ZnO nanorod arrays were prepared on silicon substrate via thermal evaporation process without any catalyst. The morphology, growth mechanism, and optical properties of the both structures were investigated using XRD, SEM, TEM and PL. The resulting comb-teeth, with a diameter about 20 nm, growing along the [0001] direction have a well-defined epitaxial relationship with the comb ribbon. The ZnO nanorod arrays have a diameter about 200 nm and length up to several micrometers growing approximately vertical to the Si substrate. A ZnO film was obtained before the nanorods growth. A growth model is proposed for interpreting the growth mechanism of comb-like zigzag-notch nanostructure. Room temperature photoluminescence measurements under excitation wavelength of 325 nm showed that the ZnO comb-like nanostructure has a weak UV emission at around 384 nm and a strong green emission around 491 nm, which correspond to a near band-edge transition and the singly ionized oxygen vacancy, respectively. In contrast, a strong and sharp UV peak and a weak green peak was obtained from the ZnO nanorod arrays.

  4. Lithium battery with solid polymer electrolyte based on comb-like copolymers

    NASA Astrophysics Data System (ADS)

    Daigle, Jean-Christophe; Vijh, Ashok; Hovington, Pierre; Gagnon, Catherine; Hamel-Pâquet, Julie; Verreault, Serge; Turcotte, Nancy; Clément, Daniel; Guerfi, Abdelbast; Zaghib, Karim

    2015-04-01

    In this paper we report on the synthesis of comb-like copolymers as solid polymer electrolytes (SPE). The synthesis involved anionic polymerization of styrene (St) and 4-vinylanisole (VA) as the followed by grafting of poly(ethylene glycol) monomethyl ether methacrylate (PEGMA) by Atom Transfer Radical Polymerization (ATRP). The comb-like copolymer's structure was analyzed by Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC). The membranes were made by solvent casting and the morphologies were analyzed by atomic forces microscopy (AFM) and scanning electron microscopy (SEM). We observed that a nano and micro phase separation occurs which improves ionic conductivity. The ionic conductivities were determined by AC Impedance, which showed that the SPEs have good conductivities (10-5 Scm-1) at room temperature owing to the negligible values (<10 kJ mol-1) of the activation energies for conductivity. The batteries with these polymers exhibit a capacity of 146 mAh g-1 at C/24, and no evidence of degradation after intense cycling was observed. However, poor cycle life was observed at C/6 and C/3, which is a consequence of several factors. We partially explain that behavior by arguing that whereas PEO lightly "solvates" Li+ thus slowing Li-ion mobility, and PEGMA chains "solvate" Li ions too strongly, trapping and inhibiting their mobility.

  5. Self-similar pulse evolution in a fiber laser with a comb-like dispersion-decreasing fiber.

    PubMed

    Tang, Yuxing; Liu, Zhanwei; Fu, Walter; Wise, Frank W

    2016-05-15

    We demonstrate an erbium fiber laser with self-similar pulse evolution inside a comb-like dispersion-decreasing fiber. We show numerically and experimentally that the comb-like dispersion-decreasing fiber works as well as an ideal one, and offers major practical advantages. The existence of a nonlinear attractor is verified by the invariant pulse chirp over a wide range of net cavity dispersion in experiments. The laser generates 1.3 nJ pulses with parabolic shapes and linear chirps, which can be dechirped to 37 fs. Comb-like dispersion-decreasing fiber should enable the generation of high-energy few-cycle pulses directly from a fiber oscillator. PMID:27176985

  6. Sustained release of protein from poly(ethylene glycol) incorporated amphiphilic comb like polymers.

    PubMed

    Srividhya, M; Preethi, S; Gnanamani, A; Reddy, B S R

    2006-12-01

    Amphiphilic comb like macromonomer containing hydrophilic poly(ethylene glycol) groups covalently linked to poly(hydromethyl siloxane) (PHMS) were prepared by hydrosilylation reaction. The epoxy reacting sites were introduced to this amphiphilic system by the reaction with allyl epoxy propyl ether (AEPE). Bovine serum albumin (BSA), a model protein drug was loaded to the PEG-PDMS system and very thin membranes were made from this macromonomer adopting solution casting technique. The in vitro protein release studies at various pH conditions showed a controlled release profile without exhibiting any initial burst. The control of the initial burst might be due to the strong linkages of the protein with the membrane and the aggregation of the protein at the surface. The morphology of the membrane before and after the protein release, and the mechanical strength were evaluated. The surface properties of the membrane were studied using the contact angle measurements. PMID:16930885

  7. Synthesis of comb-like copolymers from renewable resources: Itaconic anhydride, stearyl methacrylate and lactic acid

    NASA Astrophysics Data System (ADS)

    Shang, Shurui

    The synthesis and properties of comb-like copolymers and ionomers derived from renewable resources: itaconic anhydride (ITA), stearyl methacrylate (SM) and lactic acid (LA) are described. The copolymers based on ITA and SM (ITA-SM) were nearly random with a slight alternating tendency. The copolymers exhibited a nanophase-separated morphology, with the stearate side-chains forming a bilayer, semi-crystalline structure. The crystalline side-chains suppressed molecular motion of the main-chain, so that a glass transition temperature (Tg) was not resolved unless the ITA concentration was sufficiently high so that Tg > the melting point (Tm). The softening point and modulus of the copolymers increased with the increasing ITA concentration, but the thermal stability decreased. The ITA moiety along the main chain of the copolymers was neutralized with metal acetates to produce Na-, Ca- and Zn- random ionomers with comb-like architectures. In general, the incorporation of the ionic groups increased the Tg and suppressed the crystallinity of the side-chain packing. Ionomers with high SM side-chain density had two competing driving forces for self-assembled nano-phase separation: ionic aggregation and side-chain crystalline packing. Upon neutralization, a morphological transition from semi-crystalline lamella to spherical ionic aggregation was observed by small angle X-ray scattering (SAXS) analysis and transmission electron microscopy (TEM). Thermomechanical analysis revealed an increasing resistance to penetration deformation with an increasing degree of neutralization and an apparent rubbery plateau was observed above Tg. A controlled transesterification of PLA in glassware was an effective way to prepare a methacrylate functionalized PLA macromonomer with controlled molecular weight, which was used to synthesize a variety of copolymers. The copolymerization of this functionalized PLA macromonomer with ITA totally suppressed the side-chain crystallinity for the PLA chain

  8. Molecular self assembly of mixed comb-like dextran surfactant polymers for SPR virus detection.

    PubMed

    Mai-Ngam, Katanchalee; Kiatpathomchai, Wansika; Arunrut, Narong; Sansatsadeekul, Jitlada

    2014-11-01

    The synthesis of two comb-like dextran surfactant polymers, that are different in their dextran molecular weight (MW) distribution and the presence of carboxylic groups, and their characterization are reported. A bimodal carboxylic dextran surfactant polymer consists of poly(vinyl amine) (PVAm) backbone with carboxyl higher MW dextran, non-functionalized lower MW dextran and hydrophobic hexyl branches; while a monomodal dextran surfactant polymer is PVAm grafted with non-functionalized lower MW dextran and hexyl branches. Layer formation of non-covalently attached dextran chains with bimodal MW distributions on a surface plasmon resonance (SPR) chip was investigated from the perspective of mixed physisorption of the bimodal and monomodal surfactant polymers. Separation distances between the carboxylic longer dextran side chains within the bimodal surfactant polymer and between the whole bimodal surfactant molecules on the chip surface could be well-controlled. SPR analysis of shrimp yellow head virus using our mixed surfactant chips showed dependence on synergetic adjustment of these separation distances.

  9. Two-dimensional locally resonant elastic metamaterials with chiral comb-like interlayers: Bandgap and simultaneously double negative properties.

    PubMed

    Wang, Yan-Feng; Wang, Yue-Sheng; Zhang, Chuanzeng

    2016-06-01

    In this paper, bandgap and dynamic effective properties of two-dimensional elastic metamaterials with a chiral comb-like interlayer are studied by using the finite element method. The effects of the geometrical parameters of the chiral comb-like interlayer on the band edges are investigated and discussed. Combined with the analysis of the vibration modes at the band edges, equivalent spring-mass/pendulum models are developed to investigate the mechanisms of the bandgap generation. The analytically predicted results of the band edges, including the frequency where the double negative properties appear, and the numerical ones are generally in good agreement. The research findings in this paper have relevant engineering applications of the elastic metamaterials in the low frequency range. PMID:27369156

  10. Two-dimensional locally resonant elastic metamaterials with chiral comb-like interlayers: Bandgap and simultaneously double negative properties.

    PubMed

    Wang, Yan-Feng; Wang, Yue-Sheng; Zhang, Chuanzeng

    2016-06-01

    In this paper, bandgap and dynamic effective properties of two-dimensional elastic metamaterials with a chiral comb-like interlayer are studied by using the finite element method. The effects of the geometrical parameters of the chiral comb-like interlayer on the band edges are investigated and discussed. Combined with the analysis of the vibration modes at the band edges, equivalent spring-mass/pendulum models are developed to investigate the mechanisms of the bandgap generation. The analytically predicted results of the band edges, including the frequency where the double negative properties appear, and the numerical ones are generally in good agreement. The research findings in this paper have relevant engineering applications of the elastic metamaterials in the low frequency range.

  11. Theranostic Gold Nanomicelles made from Biocompatible Comb-like Polymers for Thermochemotherapy and Multifunctional Imaging with Rapid Clearance.

    PubMed

    Deng, Heng; Dai, Fengying; Ma, Guanghui; Zhang, Xin

    2015-06-24

    A new generation of photothermal theranostic agents based on assembling 6 nm gold nanoparticles (AuNPs) is developed by using a novel comb-like amphipathic polymer as the template. The small AuNPs are assembled into DOX@gold nanomicelles, which show strong absorbance in the near-infrared region, for multimodal bioimaging and highly effective in vivo chemotherapy and photothermal therapy. PMID:25946668

  12. Field emission of comb-like chromium disilicide nanowires prepared by an in situ chloride-generated route

    NASA Astrophysics Data System (ADS)

    Hu, Yemin; Hu, Zheng; Yu, Leshu; Li, Ying; Zhu, Mingyuan; Bai, Qin

    2011-04-01

    Large-area comb-like chromium disilicide (CrSi2) nanowire film has been successfully synthesized on silicon wafer through an in situ chloride-generated route. The sample possesses branch-like nanowires grown out perpendicularly and evenly from both sides of a stem-like microrod, forming 2-fold comb-like hierarchical nanoarchitectures. The formation mechanism of the sample could be understood by a secondary nucleation process occurring on the surface of the firstly formed CrSi2 microrod, followed by epitaxial growth of branch-like nanowires under conditions of proper temperature and sufficient vapor supply in the reaction system. The field-emission behavior of the sample shows a low turn-on field of 5.3-6.5 V/μm at anode-sample distances of 200-400 μm, and agrees well with the conventional Fowler-Nordheim theory. No obvious degradation was observed in a life stability experiment period for over 100 min. The relationship between the field enhancement factor and anode-sample distance follows a universal equation, developed within a two-region field-emission model. The convenient and low-cost preparation of the comb-like CrSi2 nanowires and their remarkable field-emission performance suggest that they can serve as good candidates for field-emission applications.

  13. Collapse of homeotropic liquid-crystal alignment by increased molecular packing on comb-like polymer surfaces.

    PubMed

    Sohn, Eun-Ho; Kang, Hyo; Kim, Dong-Gyun; Song, Kigook; Lee, Jong-Chan

    2012-06-01

    We report an unusual alignment behavior of liquid crystals (LCs) on well-ordered comb-like poly(oxyethylene) surfaces. The homeotropic LC alignments that are observed on as-coated surfaces of the polymers are transformed to the random planar type after annealing treatment, even though the molecular structure of the polymer surface becomes more ordered and the surface energy decreases. Studies of the surface properties, such as molecular structure, morphology, and wettability, reveal that such an unexpected alteration of the LC alignment originates from the density of the alkyl side chains being enhanced by localized packing. PMID:22511283

  14. Memristor comprising film with comb-like structure of nanocolumns of metal oxide embedded in a metal oxide matrix

    SciTech Connect

    Driscoll, Judith L; Lee, ShinBuhm; Jia, Quanxi

    2015-05-12

    Films having a comb-like structure of nanocolumns of Sm.sub.2O.sub.3 embedded in a SrTiO.sub.3 formed spontaneously on a substrate surface by pulsed laser deposition. In an embodiment, the nanocolumns had a width of about 20 nm with spaces between nanocolumns of about 10 nm. The films exhibited memristive behavior, and were extremely uniform and tunable. Oxygen deficiencies were located at vertical interfaces between the nanocolumns and the matrix. The substrates may be single-layered or multilayered.

  15. Synergistic anti-tumor therapy by a comb-like multifunctional antibody nanoarray with exceptionally potent activity

    NASA Astrophysics Data System (ADS)

    Li, Huafei; Sun, Yun; Chen, Di; Zhao, He; Zhao, Mengxin; Zhu, Xiandi; Ke, Changhong; Zhang, Ge; Jiang, Cheng; Zhang, Li; Zhang, Fulei; Wei, Huafeng; Li, Wei

    2015-10-01

    Simultaneously blocking multiple mediators offers new hope for the treatment of complex diseases. However, the curative potential of current combination therapy by chronological administration of separate monoclonal antibodies (mAbs) or multi-specific mAbs is still moderate due to inconvenient manipulation, low cooperative effectors, poor pharmacokinetics and insufficient tumor accumulation. Here, we describe a facile strategy that arms distinct mAbs with cooperative effectors onto a long chain to form a multicomponent comb-like nano mAb. Unlike dissociative parental mAbs, the multifunctional mAb nanoarray (PL-RB) constructed from type I/II anti-CD20 mAbs shows good pharmacokinetics. This PL-RB simultaneously targets distinct epitopes on a single antigen (Ag) and neighboring Ags on different lymphocytes. This unique intra- and intercellular Ag cross-linking endows the multifunctional mAb nanoarray with potent apoptosis activity. The exceptional apoptosis, complement-dependent cytotoxicity (CDC), antibody-dependent cellular cytotoxicity (ADCC) that are synchronously evoked by the nano PL-RB are further synergistically promoted via enhanced permeability and retention (EPR), which resulted in high intratumor accumulation and excellent anti-lymphoma efficiency.

  16. Synergistic anti-tumor therapy by a comb-like multifunctional antibody nanoarray with exceptionally potent activity

    PubMed Central

    Li, Huafei; Sun, Yun; Chen, Di; Zhao, He; Zhao, Mengxin; Zhu, Xiandi; Ke, Changhong; Zhang, Ge; Jiang, Cheng; Zhang, Li; Zhang, Fulei; Wei, Huafeng; Li, Wei

    2015-01-01

    Simultaneously blocking multiple mediators offers new hope for the treatment of complex diseases. However, the curative potential of current combination therapy by chronological administration of separate monoclonal antibodies (mAbs) or multi-specific mAbs is still moderate due to inconvenient manipulation, low cooperative effectors, poor pharmacokinetics and insufficient tumor accumulation. Here, we describe a facile strategy that arms distinct mAbs with cooperative effectors onto a long chain to form a multicomponent comb-like nano mAb. Unlike dissociative parental mAbs, the multifunctional mAb nanoarray (PL-RB) constructed from type I/II anti-CD20 mAbs shows good pharmacokinetics. This PL-RB simultaneously targets distinct epitopes on a single antigen (Ag) and neighboring Ags on different lymphocytes. This unique intra- and intercellular Ag cross-linking endows the multifunctional mAb nanoarray with potent apoptosis activity. The exceptional apoptosis, complement-dependent cytotoxicity (CDC), antibody-dependent cellular cytotoxicity (ADCC) that are synchronously evoked by the nano PL-RB are further synergistically promoted via enhanced permeability and retention (EPR), which resulted in high intratumor accumulation and excellent anti-lymphoma efficiency. PMID:26508306

  17. Wax inhibition by comb-like polymers: support of the incorporation-perturbation mechanism from molecular dynamics simulations.

    PubMed

    Jang, Yun Hee; Blanco, Mario; Creek, Jefferson; Tang, Yongchun; Goddard, William A

    2007-11-22

    Deposition of wax on a cold surface is a serious problem in oil production. Progress in developing more effective wax inhibitors has been impeded by the lack of an established mechanism connecting the molecular structure to inhibitor efficiency. Some comb-like polymers having long alkyl side chains are known to decrease the rate of wax formation. Among several possible mechanisms, we investigate here the incorporation-perturbation mechanism. According to this mechanism, the inhibitor molecules in oil are preferentially partitioned (incorporation) toward the wax-rich (amorphous) wax deposits (soft wax), which then serves as a perturbation to slow down the ordering transition of soft amorphous wax into more stable but problematic hard wax crystals. Indeed, molecular dynamics simulations on an effective inhibitor molecule in both the oil phase and in the amorphous wax phase support the idea that the oil-to-wax partition of the inhibitor is energetically favorable. With the inhibitor molecule embedded, the structure of wax crystal is disturbed, significantly decreasing the order and significantly lowering the cohesive energy density relative to that of the pure wax crystal, supporting the slower transition from soft wax to hard wax. Thus, in the presence of an effective wax inhibitor, crystallization (formation of hard wax) is slowed dramatically, so that there is time to flush out the soft wax with a high-pressure flow inside the pipeline. This suggests design principles for developing improved wax inhibitors. PMID:17975910

  18. Surface-grafted polystyrene beads with comb-like poly(ethylene glycol) chains: preparation and biological application.

    PubMed

    Byun, Jang-Woong; Kim, Jong-Uk; Chung, Woo-Jae; Lee, Yoon-Sik

    2004-05-17

    We prepared surface-grafted polystyrene (PS) beads with comb-like poly(ethylene glycol) (PEG) chains. To accomplish this, conventional gel-type PS beads (35-75 microm) were treated with ozone gas to introduce hydroperoxide groups onto the surface. Using these hydroperoxide groups, poly(methyl methacrylate) (PMMA, Mn= 22,000-25,000) was grafted onto the surface of the PS beads. The ester groups of the grafted PMMA were reduced to hydroxyl groups with lithium aluminum hydride (LAH). After adding ethylene oxide (EO) to the hydroxyl groups, we obtained the PS-sg-PEG beads, which had a rugged surface and a diameter of 80-150 microm. We could obtain several kinds of the PS-sg-PEG beads by controlling the chain lengths of the grafted PMMA and the molecular weights of the PEG chains. The grafted PEG layer was about 30-50 microm thick, which was verified from the cross-sectioned views of the fluorescamine-labeled beads. These fluorescence images proved that the beads possessed a pellicular structure. Furthermore, we found that the surface-grafted PEG chains had the characteristic property of reducing non-specific protein adsorption on the beads.

  19. Molecular dynamics in nanophase-separated comb-like poly(alpha-n-alkyl beta-L-aspartate)s.

    PubMed

    Grimau, M; Laredo, E; Sánchez, F; López-Carrasquero, F; Báez, M E; Bello, A

    2004-12-01

    A series of poly(alpha-n-alkyl beta-L-aspartates) which are nanophase self-assembled comb-like polymers has been studied by dielectric spectroscopy in a broad frequency range (10(-2) < or = nu < or = 3 x 10(6) Hz), with n-alkyls side chains of various lengths, 10 < or = n < or =18. In every member of the series the same relaxations were identified after the decomposition of the experimental isothermal trace in up to three peaks with relaxation times distributions. The strength, width and average relaxation time for all the relaxation modes were determined for each material. Besides the local low temperature, Arrhenius modes, two relaxation modes, alpha and alpha(PE), present a cooperative character whose dynamics are not affected by the side chains melting. The alpha(PE) relaxation is a polyethylene-like glass transition of the amorphous side chains and its dynamics is strongly dependent on the n value due to the increasing restrictions imposed by the self-assembled confinement. The strength of the alpha(PE) relaxation mode increases as the lateral chains loose their 2D order. The restricted chopstick motion of the rigid rods is thought to be the origin of the alpha mode; this motion is hindered at temperatures where the cage size decreases as a result of the increasing disorder with temperature.

  20. Comb-like amphiphilic polypeptide-based copolymer nanomicelles for co-delivery of doxorubicin and P-gp siRNA into MCF-7 cells.

    PubMed

    Suo, Aili; Qian, Junmin; Zhang, Yaping; Liu, Rongrong; Xu, Weijun; Wang, Hejing

    2016-05-01

    A comb-like amphiphilic copolymer methoxypolyethylene glycol-graft-poly(L-lysine)-block-poly(L-phenylalanine) (mPEG-g-PLL-b-Phe) was successfully synthesized. To synthesize mPEG-g-PLL-b-Phe, diblock copolymer PLL-b-Phe was first synthesized by successive ring-opening polymerization of α-amino acid N-carboxyanhydrides followed by the removal of benzyloxycarbonyl protecting groups, and then mPEG was grafted onto PLL-b-Phe by reductive amination via Schiff's base formation. The chemical structures of the copolymers were identified by (1)H NMR. mPEG-g-PLL-b-Phe copolymer had a critical micelle concentration of 6.0mg/L and could self-assemble in an aqueous solution into multicompartment nanomicelles with a mean diameter of approximately 78 nm. The nanomicelles could encapsulate doxorubicin (DOX) through hydrophobic and π-π stacking interactions between DOX molecules and Phe blocks and simultaneously complex P-gp siRNA with cationic PLL blocks via electrostatic interactions. The DOX/P-gp siRNA-loaded nanomicelles showed spherical morphology, possessed narrow particle size distribution and had a mean particle size of 120 nm. The DOX/P-gp siRNA-loaded nanomicelles exhibited pH-responsive release behaviors and displayed accelerated release under acidic conditions. The DOX/P-gp siRNA-loaded nanomicelles were efficiently internalized into MCF-7 cells, and DOX released could successfully reach nuclei. In vitro cytotoxicity assay demonstrated that the DOX/P-gp siRNA-loaded nanomicelles showed a much higher cytotoxicity in MCF-7 cells than DOX-loaded nanomicelles due to their synergistic killing effect and that the blank nanomicelles had good biocompatibility. Thus, the novel comb-like mPEG-g-PLL-b-Phe nanomicelles could be a promising vehicle for co-delivery of chemotherapeutic drug and genetic material.

  1. A comb-like branched β-D-glucan produced by a Cordyceps sinensis fungus and its protective effect against cyclophosphamide-induced immunosuppression in mice.

    PubMed

    Hu, Ting; Jiang, Chenbo; Huang, Qilin; Sun, Fengyuan

    2016-05-20

    An exopolysaccharide (EPS) was fractionated from fermentation media of a Cordyceps sinensis fungus (Cs-HK1) by ethanol precipitation at 2/5 volume ratio of ethanol/media. Its structural characteristics were elucidated by FT-IR, GC, GC-MS, 1D and 2D NMR combined with periodate oxidation, Smith degradation, partial acid hydrolysis, and methylation analysis. Furthermore, the immunomodulatory activity of EPS was evaluated by the model of cyclophosphamide-induced immunosuppression. The results from monosaccharide composition and partial acid hydrolysis indicated that EPS almost consisted of glucose excluding a trace amount of mannose. GC-MS and NMR analysis further confirmed EPS had a linear backbone of (1→3)-β-D-glucopyranosyl residues with a single (1→6)-β-D-glucopyranosyl side-branching unit for every three β-D-glucopyranosyl residues, showing a comb-like β-D-glucan with short and intensive branches, which was responsible for high viscosity. Moreover, EPS could significantly enhance immune organs and stimulate the release of major cytokines TNF-α and INF-γ, suggesting that EPS exhibited protective effect in immunocompromised mice. PMID:26917398

  2. Comb-like amphiphilic copolymers bearing acetal-functionalized backbones with the ability of acid-triggered hydrophobic-to-hydrophilic transition as effective nanocarriers for intracellular release of curcumin.

    PubMed

    Zhao, Junqiang; Wang, Haiyang; Liu, Jinjian; Deng, Liandong; Liu, Jianfeng; Dong, Anjie; Zhang, Jianhua

    2013-11-11

    The pH-responsive micelles have enormous potential as nanosized drug carriers for cancer therapy due to their physicochemical changes in response to the tumor intracellular acidic microenvironment. Herein, a series of comb-like amphiphilic copolymers bearing acetal-functionalized backbone were developed based on poly[(2,4,6-trimethoxybenzylidene-1,1,1-tris(hydroxymethyl) ethane methacrylate-co-poly(ethylene glycol) methyl ether methacrylate] [P(TTMA-co-mPEGMA)] as effective nanocarriers for intracellular curcumin (CUR) release. P(TTMA-co-mPEGMA) copolymers with different hydrophobic-hydrophilic ratios were prepared by one-step reversible addition fragmentation chain transfer (RAFT) copolymerization of TTMA and mPEGMA. Their molecular structures and chemical compositions were confirmed by (1)H NMR, Fourier transform infrared spectroscopy (FT-IR) and gel permeation chromatography (GPC). P(TTMA-co-mPEGMA) copolymers could self-assemble into nanosized micelles in aqueous solution and displayed low critical micelle concentration (CMC). All P(TTMA-co-mPEGMA) micelles displayed excellent drug loading capacity, due to the strong π-π conjugate action and hydrophobic interaction between the PTTMA and CUR. Moreover, the hydrophobic PTTMA chain could be selectively hydrolyzed into a hydrophilic backbone in the mildly acidic environment, leading to significant swelling and final disassembly of the micelles. These morphological changes of P(TTMA-co-mPEGMA) micelles with time at pH 5.0 were determined by DLS and TEM. The in vitro CUR release from the micelles exhibited a pH-dependent behavior. The release rate of CUR was significantly accelerated at mildly acidic pH of 4.0 and 5.0 compared to that at pH 7.4. Toxicity test revealed that the P(TTMA-co-mPEGMA) copolymers exhibited low cytotoxicity, whereas the CUR-loaded micelles maintained high cytotoxicity for HepG-2 and EC-109 cells. The results indicated that the novel P(TTMA-co-mPEGMA) micelles with low CMC, small and tunable

  3. Additives

    NASA Technical Reports Server (NTRS)

    Smalheer, C. V.

    1973-01-01

    The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

  4. The codevelopment of skill at and preference for use of retrieval-based processes for solving addition problems: individual and sex differences from first to sixth grades.

    PubMed

    Bailey, Drew H; Littlefield, Andrew; Geary, David C

    2012-09-01

    The ability to retrieve basic arithmetic facts from long-term memory contributes to individual and perhaps sex differences in mathematics achievement. The current study tracked the codevelopment of preference for using retrieval over other strategies to solve single-digit addition problems, independent of accuracy, and skilled use of retrieval (i.e., accuracy and reaction time [RT]) from first to sixth grades inclusive (N=311). Accurate retrieval in first grade was related to working memory capacity and intelligence, and it predicted a preference for retrieval in second grade. In later grades, the relation between skill and preference changed such that preference in one grade predicted accuracy and RT in the next grade as RT and accuracy continued to predict future gains in preference. In comparison with girls, boys had a consistent preference for retrieval over other strategies and had faster retrieval speeds, but the sex difference in retrieval accuracy varied across grades. Results indicate that ability influences early skilled retrieval, but both practice and skill influence each other in a feedback loop later in development and provide insights into the source of the sex difference in problem-solving approaches.

  5. Predictors of victim disclosure in child sexual abuse: Additional evidence from a sample of incarcerated adult sex offenders.

    PubMed

    Leclerc, Benoit; Wortley, Richard

    2015-05-01

    The under-reporting of child sexual abuse by victims is a serious problem that may prolong the suffering of victims and leave perpetrators free to continue offending. Yet empirical evidence indicates that victim disclosure rates are low. In this study, we perform regression analysis with a sample of 369 adult child sexual offenders to examine potential predictors of victim disclosure. Specifically, we extend the range of previously examined potential predictors of victim disclosure and investigate interaction effects in order to better capture under which circumstances victim disclosure is more likely. The current study differs from previous studies in that it examines the impact of victim and offense variables on victim disclosure from the perspective of the offender. In line with previous studies, we found that disclosure increased with the age of the victim and if penetration had occurred. In addition, we found that disclosure increased when the victim came from a non-dysfunctional family and resisted the abuse. The presence of an interaction effect highlighted the impact of the situation on victim disclosure. This effect indicated that as victims get older, they are more likely to disclose the abuse when they are not living with the offender at the time of abuse, but less likely to do so when they are living with the offender at the time of abuse. These findings are discussed in relation to previous studies and the need to facilitate victim disclosure.

  6. The Co-Development of Skill at and Preference for Use of Retrieval-Based Processes for Solving Addition Problems: Individual and Sex Differences from First to Sixth Grade

    PubMed Central

    Bailey, Drew H.; Littlefield, Andrew; Geary, David C.

    2012-01-01

    The ability to retrieve basic arithmetic facts from long-term memory contributes to individual and perhaps sex differences in mathematics achievement. The current study tracked the co-development of preference for using retrieval over other strategies to solve single-digit addition problems, independent of accuracy, and skilled use of retrieval (i.e., accuracy and RT) from first to sixth grade, inclusive (n = 311). Accurate retrieval in first grade was related to working memory capacity and intelligence and predicted a preference for retrieval in second grade. In later grades, the relation between skill and preference changed such that preference in one grade predicted accuracy and RT in the next, as RT and accuracy continued to predict future gains in preference. In comparison to girls, boys had a consistent preference for retrieval over other strategies and had faster retrieval speeds, but the sex difference in retrieval accuracy varied across grades. Results indicate ability influences early skilled retrieval but both practice and skill influence each other in a feedback loop later in development, and provide insights into the source of the sex difference in problem solving approaches. PMID:22704036

  7. Clinically insignificant improvement of prostate cancer prediction by addition of sex steroid hormones and SHBG serum levels to serum PSA, fPSA%, and age in a screening setting.

    PubMed

    Heidegger, Isabel; Popovscaia, Marina; Ramoner, Reinhold; Schäfer, Georg; Stenzel, Birgit; Bektic, Jasmin; Horninger, Wolfgang; Klocker, Helmut

    2012-10-01

    Abstract Various findings implicate sex hormones in prostate growth and development and also in prostate carcinogenesis. We investigated if addition of sex steroid hormone and sex hormone binding globulin (SHBG) serum levels to standard risk assessment parameters [prostate-specific antigen (PSA), free PSA percentage (fPSA%), and age] improves prostate cancer prediction in a PSA screening setting. Steroid hormones testosterone (T), free testosterone (fT), and estradiol (E2), and binding protein SHBG levels were measured in 762 men undergoing prostate biopsy due to suspect PSA serum levels. Prostate cancer was diagnosed in 286 (37.5%) of these men. Our data confirmed that PSA (mean BE=5.09; mean CA=6.05; p=1.24×10-5), fPSA% (mean BE=22.08; mean CA=18.67; p=1.97×10-7), and age (mean BE=60.64; mean CA=64.5; p=7.05×10-10) differentiate men with cancer (CA) and men with benign disease (BE), such as benign prostate hyperplasia. In addition, SHBG (mean BE=50.3; mean CA=54.9; p=0.008) also differed statistically significantly between these two groups. All hormones except E2 and tumor markers correlated significantly with age (T: ρ=-0.09; fT: ρ=-0.27; SHBG: ρ=0.21; PSA: ρ=0.32; and fPSA%: ρ=0.22). Furthermore, we found that PSA correlates with E2 (ρ=0.08), and fPSA% with SHBG (ρ=0.1) and fT (ρ=-0.09). Addition of hormones and SHBG to a baseline marker model including PSA, fPSA%, and age improved cancer prediction in three multivariate classification methods; however, the improvement was minimal. The best improvement by 0.8% was obtained in the logistic regression model with the addition of T and SHBG or of E2 and SHBG, or in the support vector machine model with the addition of SHBG and all steroid hormones to the combination of standard markers PSA, fPSA%, and age; however, this additional gain of accuracy is too small to justify the additional efforts and costs.

  8. Sex determination in amphibians.

    PubMed

    Nakamura, Masahisa

    2009-05-01

    The heterogametic sex is male in all mammals, whereas it is female in almost all birds. By contrast, there are two heterogametic types (XX/XY and ZZ/ZW) for genetic sex determination in amphibians. Though the original heterogametic sex was female in amphibians, the two heterogametic types were probably interchangeable, suggesting that sex chromosomes evolved several times in this lineage. Indeed, the frog Rana rugosa has the XX/XY and ZZ/ZW sex-determining systems within a single species, depending on the local population in Japan. The XY and ZW geographic forms with differentiated sex chromosomes probably have a common origin as undifferentiated sex chromosomes resulted from the hybridization between the primary populations of West Japan and Kanto forms. It is clear that the sex chromosomes are still undergoing evolution in this species group. Regardless of the presence of a sex-determining gene in amphibians, the gonadal sex of some species can be changed by sex steroids. Namely, sex steroids can induce the sex reversal, with estrogens inducing the male-to-female sex reversal, whereas androgens have the opposite effect. In R. rugosa, gonadal activity of CYP19 (P450 aromatase) is correlated with the feminization of gonads. Of particular interest is that high levels of CYP19 expression are observed in indifferent gonads at time before sex determination. Increases in the expression of CYP19 in female gonads and CYP17 (P450 17alpha-hydroxylase/C17-20 lyase) in male gonads suggest that the former plays an important role in phenotypic female determination, whereas the latter is needed for male determination. Thus, steroids could be the key factor for sex determination in R. rugosa. In addition to the role of sex steroids in gonadal sex determination in this species, Foxl2 and Sox3 are capable of promoting CYP19 expression. Since both the genes are autosomal, another factor up-regulating CYP19 expression must be recruited. The factor, which may be located on the X or W

  9. Sex Films

    ERIC Educational Resources Information Center

    Francoeur, Robert T.

    1977-01-01

    Describes a new concept in sex education, the sexual attitudes reassessment workshop. This workshop satiates, saturates, desensitizes, and demythologizes sex. It bypasses the intellect and forces people to deal with feeling and attitudes. (Author/AM)

  10. How to sell safer sex.

    PubMed

    Overs, C

    1991-09-01

    Social and economic factors determine the extent of the sex industry in societies. Despite AIDS, the sex industry will continue to thrive. Accordingly, health promotion strategies aimed at sex workers and their clients should not stem from the belief that the industry should cease to exist. This paper offers advice in developing and implementing programs to promote safer sex among sex workers. The social context is 1 element to consider in planning successful campaigns. Interventions must be combined with well-planned prevention campaigns aimed at entire populations. The opinions and participation of those involved in the industry should also be sought, while worker discussion and action upon other community issues should not be discouraged. Care should be given to target the numerous and diverse sex worker audiences in addition to other persons related to and involved in the industry. Programs should address the main obstacles to practicing safer sex, and attention should be given to ensure the provision of an adequate and regular supply of cheap or free condoms through varied distribution channels. In the area of service provision, sex workers need easy access to social support and health care services from which they are often excluded. Activities conducted around the world include the marketing of safer sex, distributing printed information on HIV and AIDS to clients, training sex workers to pass designated constructive ideas to others involved in the sex industry, referring sex workers to sex businesses supportive of safer sex practices, and developing street theater and cabaret shows in bars.

  11. Sex differences in stroke.

    PubMed

    Haast, Roy A M; Gustafson, Deborah R; Kiliaan, Amanda J

    2012-12-01

    Sex differences in stroke are observed across epidemiologic studies, pathophysiology, treatments, and outcomes. These sex differences have profound implications for effective prevention and treatment and are the focus of this review. Epidemiologic studies reveal a clear age-by-sex interaction in stroke prevalence, incidence, and mortality. While premenopausal women experience fewer strokes than men of comparable age, stroke rates increase among postmenopausal women compared with age-matched men. This postmenopausal phenomenon, in combination with living longer, are reasons for women being older at stroke onset and suffering more severe strokes. Thus, a primary focus of stroke prevention has been based on sex steroid hormone-dependent mechanisms. Sex hormones affect different (patho)physiologic functions of the cerebral circulation. Clarifying the impact of sex hormones on cerebral vasculature using suitable animal models is essential to elucidate male-female differences in stroke pathophysiology and development of sex-specific treatments. Much remains to be learned about sex differences in stroke as anatomic and genetic factors may also contribute, revealing its multifactorial nature. In addition, the aftermath of stroke appears to be more adverse in women than in men, again based on older age at stroke onset, longer prehospital delays, and potentially, differences in treatment.

  12. Sex preferences in Turkey.

    PubMed

    Unalan, T

    1993-01-01

    The analysis of data from the 1988 Turkish Population and Health Survey showed an overall sex ratio of 103 males per 100 females. The sex ratio was 125 for women with one child and 95 for women with 5 or more children. The sex ratio was 119 for the last child and 94 for all children. The sex ratio was 74 for women desiring another child and 108 for women wanting no more children. The sex ratio was high for women who wanted to stop childbearing after the first birth. The implication was that women were willing to stop or delay childbearing after a son's first birth. 33% of women had no sex preference for their next child, among those women desiring an additional child. 41.9% desired a boy and 25.0% desired a girl in 1978; in 1988, 38.8% desired a boy and 29.2% desired a girl. Those answering that future births were up to God declined from 7% in 1978 to 4% in 1988. Among women with 1 child, over 70% desired a child of the opposite sex. Almost 90% of women with no boy or girl wanted a child of that sex. 36.5% desired a boy if their first child was a boy and 6.8% desired a girl. If there were 2 sons, 87.5% desired a girl and 5.5% desired a boy. 59.7% desired a boy and a girl, and 12.1% desired 2 boys and 1 girl. Almost 10% desired no children. There was a stronger desire for sons, particularly among those desiring only 1 child. The sex ratio was 112 for women without children but desiring children. In the absence of sex preference, 3.5% more would desire no more children and contraceptive use would increase by 1.8%.

  13. Safe sex.

    PubMed

    Mukherjee, G; Ghosh, T K

    1994-01-01

    The main objectives of health care for people with AIDS are to help them adjust to changing sexual status and to provide them with information on safe sex. Sections consider the risks of various types of sexual activity and safe sex education. With regard to the risk of transmitting or contracting HIV, sexual activities may be high risk, medium risk, low risk, or no risk. High-risk activities include unprotected anal or vaginal intercourse, oral-anal sexual contact, sharing sex toys, and traumatic sexual activity. Medium-risk activities include anal and vaginal intercourse using a latex condom with or without spermicide, and sex using a vaginal diaphragm or contraceptive vaginal sponge. Oral sex on a woman or oral sex on a man without ejaculation into the mouth are low-risk activities. Mutual masturbation, erotic touching, caressing and massage, kissing and non-genital licking pose no risk of infection. All general practitioners and family physicians should teach about safe sex. Prevention messages may be conveyed through individual and social counseling as well as with printed media and other forms of mass media. Messages should definitely reach prostitutes and brothel owners, as well as pre-pubertal children and older youths. PMID:8207282

  14. Safe sex.

    PubMed

    Mukherjee, G; Ghosh, T K

    1994-01-01

    The main objectives of health care for people with AIDS are to help them adjust to changing sexual status and to provide them with information on safe sex. Sections consider the risks of various types of sexual activity and safe sex education. With regard to the risk of transmitting or contracting HIV, sexual activities may be high risk, medium risk, low risk, or no risk. High-risk activities include unprotected anal or vaginal intercourse, oral-anal sexual contact, sharing sex toys, and traumatic sexual activity. Medium-risk activities include anal and vaginal intercourse using a latex condom with or without spermicide, and sex using a vaginal diaphragm or contraceptive vaginal sponge. Oral sex on a woman or oral sex on a man without ejaculation into the mouth are low-risk activities. Mutual masturbation, erotic touching, caressing and massage, kissing and non-genital licking pose no risk of infection. All general practitioners and family physicians should teach about safe sex. Prevention messages may be conveyed through individual and social counseling as well as with printed media and other forms of mass media. Messages should definitely reach prostitutes and brothel owners, as well as pre-pubertal children and older youths.

  15. Sex education in Portugal.

    PubMed

    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

  16. Adaptive value of sex in microbial pathogens.

    PubMed

    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

  17. Moral Pluralism and Sex Education

    ERIC Educational Resources Information Center

    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…

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

    PubMed

    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. PMID:27433022

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

    PubMed

    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.

  20. Sex Education.

    ERIC Educational Resources Information Center

    Williams, Sue

    1991-01-01

    This discussion of sex education for individuals with intellectual disabilities outlines Delys Sergeant's "coat hanger theory," which involves three coats or phases of sexuality: a physiological stimulus response coat; a reproductive coat; and a coat of attitudes, values, and self-esteem. Influences acting on individuals' sexuality include family,…

  1. Factors affecting attitudes toward juvenile sex offenders.

    PubMed

    Sahlstrom, Kimberly J; Jeglic, Elizabeth L

    2008-01-01

    This study investigated attitudes toward juvenile sex offenders and factors influencing those attitudes. Additionally, the influences of perpetrator characteristics such as age, gender, and ethnicity on societal attitudes towards intervention requirements were also investigated. Overall, attitudes toward juvenile sex offenders and their treatment amenability were negative. No differences in attitudes toward juvenile sex offenders were found between those who had been victims of sexual abuse and those that had not. Sex offenses committed by juvenile female sex offenders were viewed to be more serious and require more intervention than those committed by juvenile male sex offenders. PMID:19042245

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

    PubMed Central

    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 environment has sex-specific fitness consequences. Additionally, one sex is assumed to be more costly to produce than the other, which leads offspring to favor a sex ratio less biased toward the cheaper sex in comparison to the sex ratio favored by mothers. The scope for parent–offspring conflict depends on the relative frequency of both environments: when one environment is less common than the other, parent–offspring conflict can be reduced or even entirely absent, despite a biased population sex ratio. The model shows that conflict-driven invasions of condition-independent sex factors (e.g., sex chromosomes) result either in the loss of condition-dependent sex allocation, or, interestingly, lead to stable mixtures of condition-dependent and condition-independent sex factors. The latter outcome corresponds to empirical observations in which sex chromosomes are present in organisms with environment-dependent sex determination. Finally, conflict can also favor errors in environmental perception, potentially resulting in the loss of condition-dependent sex allocation without genetic changes to sex-determining loci. PMID:25180669

  3. [Lethal sex].

    PubMed

    Rabinerson, David; Ben-Shitrit, Gadi; Glezerman, Marek

    2011-03-01

    Asphyxiophilic sex is a form of autoerotic activity, in which the user creates mechanical means (such as hanging or bondage) in order to achieve cerebral hypoxia, which, in turn, enhances sexual, as well as orgasmic, stimulus. Failure of safety mechanisms, created by the user, may lead to instant death as a result of asphyxiation or strangulation. This kind of sexual practice is more prevalent among men than in women. In cases of death, it is difficult to relate it to the sexual practice itself. Suicide and homicide are the main differential diagnoses. Closely related derivatives of asphyxiophilic sex are anesthesiophilia (inhalation of variable volatile substances) and electrophilia (use of electric current during sexual activity)--both also intended to enhance the sexual stimulation. These forms of sexual practice are less prevalent than asphyxiophilia. PMID:21574359

  4. Balance of the Sexes: Addressing Sex Differences in Preclinical Research

    PubMed Central

    Zakiniaeiz, Yasmin; Cosgrove, Kelly P.; Potenza, Marc N.; Mazure, Carolyn M.

    2016-01-01

    Preclinical research is fundamental for the advancement of biomedical sciences and enhancing healthcare. Considering sex differences in all studies throughout the entire biomedical research pipeline is necessary to adequately inform clinical research and improve health outcomes. However, there is a paucity of information to date on sex differences in preclinical work. As of 2009, most (about 80 percent) rodent studies across 10 fields of biology were still conducted with only male animals. In 2016, the National Institutes of Health implemented a policy aimed to address this concern by requiring the consideration of sex as a biological variable in preclinical research grant applications. This perspective piece aims to (1) provide a brief history of female inclusion in biomedical research, (2) describe the importance of studying sex differences, (3) explain possible reasons for opposition of female inclusion, and (4) present potential additional solutions to reduce sex bias in preclinical research. PMID:27354851

  5. When Sex Is Painful

    MedlinePlus

    ... 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 ...

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

    PubMed

    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. PMID:24464550

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

    PubMed

    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.

  8. Sex reduces genetic variation: a multidisciplinary review.

    PubMed

    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.

  9. Predictors of Safer Sex Intentions and Protected Sex Among Heterosexual HIV-Negative Methamphetamine Users

    PubMed Central

    Mausbach, Brent T.; Semple, Shirley J.; Strathdee, Steffanie A; Patterson, Thomas L.

    2009-01-01

    The purpose of this study was to test a version of the Theory of Planned Behavior (TPB) for predicting safe sex behavior in a sample of 228 HIV-negative heterosexual methamphetamine users. We hypothesized that, in addition to TPB constructs, participants’ amount of methamphetamine use and desire to stop unsafe sex behaviors would predict intentions to engage in safer sex behaviors. In turn, we predicted that safer sex intentions would be positively correlated with participants’ percentage of protected sex. Hierarchical linear regression indicated that 48% of the total variance in safer sex intentions was predicted by our model, with less negative attitudes toward safer sex, greater normative beliefs, greater control beliefs, less methamphetamine use, less intent to have sex, and greater desire to stop unsafe sex emerging as significant predictors of greater safer sex intentions. Safer sex intentions were positively associated with future percent protected sex (p<.05). These findings suggest that, among heterosexual methamphetamine users, the TPB is an excellent model for predicting safer sex practices in this population, as are some additional factors (e.g., methamphetamine use). Effective interventions for increasing safer sex practices in methamphetamine user will likely include constructs from this model with augmentations to help reduce methamphetamine use. PMID:19085216

  10. Origin of Sex Revisited

    NASA Astrophysics Data System (ADS)

    Santos, Mauro; Zintzaras, Elias; Szathmáry, Eörs

    2003-10-01

    Why did sex ever arise in the first place? Why it does not disappear in view of the greater efficiency of asexuals? These are clearly two different questions, and we suggest here that the solution for the origin of sex does not necessarily come from theoretical considerations based on currently existing genetic systems. Thus, while we agree with a number of authors in that the emergence of sex (understood as the exchange of genetic material between genomes) is deeply rooted in the origin of life and happened during the very early stages in the transition from individual genes (`replicators') to bacteria-like cells (`reproducers'), we challenge the idea that recombinational repair was the major selective force for the emergence of sex. Taking the stochastic corrector model as a starting point, we provide arguments that question the putative costs of redundancy in primitive protocells. In addition, if genes that cause intragenomic conflict (i.e., parasites) are taken into account, it is certainly wrong to suggest that cellular fusion would be beneficial at the population level (although this strong claim needs some qualifications). However, when a continuous input of deleterious mutations that impair the fitness of the protocell as a whole is considered in the model (in the realistic range in which stable mutant distributions of quasi-species within compartments are established), there are circumstances when sex could be beneficial as a side effect of the dynamic equilibrium between cellular fusion-mutation-selection. The scenario we have explored numerically is fully consistent with the idea that the universal ancestor was not a discrete entity but an ensemble of proto-organisms that exchanged much genetic information.

  11. Sex-linked dominant

    MedlinePlus

    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 ...

  12. Genomics of Sex and Sex Chromosomes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sex chromosomes are distinctive, not only because of their gender determining role, but also for genomic features that reflect their evolutionary history. The genomic sequences in the ancient sex chromosomes of humans and in the incipient sex chromosomes of medaka, stickleback, and papaya exhibit u...

  13. Food additives

    PubMed Central

    Spencer, Michael

    1974-01-01

    Food additives are discussed from the food technology point of view. The reasons for their use are summarized: (1) to protect food from chemical and microbiological attack; (2) to even out seasonal supplies; (3) to improve their eating quality; (4) to improve their nutritional value. The various types of food additives are considered, e.g. colours, flavours, emulsifiers, bread and flour additives, preservatives, and nutritional additives. The paper concludes with consideration of those circumstances in which the use of additives is (a) justified and (b) unjustified. PMID:4467857

  14. Highly efficient blazed gratings based on gradient-comb-like units

    NASA Astrophysics Data System (ADS)

    Tang, Kun; Qiu, Chunyin; Lu, Jiuyang; Ke, Manzhu; Liu, Zhengyou

    2015-08-01

    Here we propose a multi-scaled reflective grating with excellent blazed performance (nearly perfect blazed effect at the well-predicted frequency and orientation). The blazed grating consists of a periodical array of metallic super-cells, each made of several equal-distant subwavelength slits with linearly reduced depth. A simple model based on Huygens-Fresnel principle is established to forecast the microwave response for the incidence of different polarizations: for transverse-electric polarization, the structure provides only the ordinary total reflection (i.e., without orientation deflected); for transverse-magnetic (TM) polarization, the waves are deflected to specific orientation due to the linear phase delay of the slit exits. Similar design route can be extended to acoustic systems, considering the mathematic similarity between the acoustic wave and the electromagnetic wave of TM-polarization.

  15. Growth of Comb-like ZnO Nanostructures for Dye-sensitized Solar Cells Applications

    PubMed Central

    2009-01-01

    Dye-sensitized solar cells (DSSCs) were fabricated by using well-crystallized ZnO nanocombs directly grown onto the fluorine-doped tin oxide (FTO) via noncatalytic thermal evaporation process. The thin films of as-grown ZnO nanocombs were used as photoanode materials to fabricate the DSSCs, which exhibited an overall light to electricity conversion efficiency of 0.68% with a fill factor of 34%, short-circuit current of 3.14 mA/cm2, and open-circuit voltage of 0.671 V. To the best of our knowledge, this is first report in which thin film of ZnO nanocombs was used as photoanode materials to fabricate the DSSCs. PMID:20596445

  16. The Riddle of Sex.

    ERIC Educational Resources Information Center

    Sagan, Dorion; Margulis, Lynn

    1985-01-01

    Discusses the work of evolutionary biologists in determining how sexual reproduction arose. Topics explored include the nature of sex, bacterial sex, meiotic sex, and asexual reproduction. A diagram (which can be used as a duplicating master) illustrating types of bacterial sex is included. (DH)

  17. Sex Education for Patients

    PubMed Central

    Zitner, David

    1985-01-01

    Sex education evokes a wide variety of responses in the community and from teachers. Consequently, physicians have a responsibility to present sex education material in a factual, objective way. Many people are misinformed about sexual behavior. Physicians can help patients and the community by being aware of appropriate sex education for each age group. A curriculum for sex education, and opportunities to provide sex information for patients of different ages and stages in the lifecycle, are described. PMID:21274069

  18. Factors Affecting Attitudes toward Juvenile Sex Offenders

    ERIC Educational Resources Information Center

    Sahlstrom, Kimberly J.; Jeglic, Elizabeth L.

    2008-01-01

    This study investigated attitudes toward juvenile sex offenders and factors influencing those attitudes. Additionally, the influences of perpetrator characteristics such as age, gender, and ethnicity on societal attitudes towards intervention requirements were also investigated. Overall, attitudes toward juvenile sex offenders and their treatment…

  19. Sex Work among Men Who Have Sex with Men and Transgender Women in Bogotá

    PubMed Central

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

    2014-01-01

    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 a 26 displaced individuals who had done sex work: 14 were men who have sex with men (MSM) 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. PMID:24464550

  20. Unisexual cucumber flowers, sex and sex differentiation.

    PubMed

    Bai, Shu-Nong; Xu, Zhi-Hong

    2013-01-01

    Sex is a universal phenomenon in the world of eukaryotes. Attempts have been made to understand regulatory mechanisms for plant sex determination by investigating unisexual flowers. The cucumber plant is one of the model systems for studying how sex determination is regulated by phytohormones. A systematic investigation of the development of unisexual cucumber flowers is summarized here, and it is suggested that the mechanism of the unisexual flower can help us to understand how the process leading to one type of gametogenesis is prevented. Based on these findings, we concluded that the unisexual cucumber flowers is not an issue of sex differentiation, but instead a mechanism for avoiding self-pollination. Sex differentiation is essentially the divergent point(s) leading to heterogametogenesis. On the basis of analyses of sex differentiation in unicellular organisms and animals as well as the core process of plant life cycle, a concept of "sexual reproduction cycle" is proposed for understanding the essential role of sex and a "progressive model" for future investigations of sex differentiation in plants.

  1. HIV and female sex workers.

    PubMed

    Estébanez, P; Fitch, K; Nájera, R

    1993-01-01

    In this review of published findings on human immunodeficiency virus (HIV) infection and risk factors among female sex workers, we summarize the results of seroprevalence studies in different countries and discuss the different patterns of transmission among such workers in various geographical regions. The highest rates of HIV infection occur in sub-Saharan Africa, where the widespread existence of sexually transmitted diseases may play an important role in sustaining transmission. In Europe and North America injecting drug use continues to be the major factor associated with HIV infection among female sex workers, while in Latin America and parts of Asia there is a more mixed pattern of heterosexual and parenteral transmission from injecting drug use. Reviewed also are studies of the risk factors associated with HIV infection among female sex workers, such as drug use, sexual behaviour, the presence of sexually transmitted diseases, and condom use; in addition, we comment on some studies of the clients of sex workers. Finally, we propose directions that future research in this area might take and discuss various interventions that need to be undertaken to reduce HIV transmission among female sex workers.

  2. HIV and female sex workers.

    PubMed Central

    Estébanez, P.; Fitch, K.; Nájera, R.

    1993-01-01

    In this review of published findings on human immunodeficiency virus (HIV) infection and risk factors among female sex workers, we summarize the results of seroprevalence studies in different countries and discuss the different patterns of transmission among such workers in various geographical regions. The highest rates of HIV infection occur in sub-Saharan Africa, where the widespread existence of sexually transmitted diseases may play an important role in sustaining transmission. In Europe and North America injecting drug use continues to be the major factor associated with HIV infection among female sex workers, while in Latin America and parts of Asia there is a more mixed pattern of heterosexual and parenteral transmission from injecting drug use. Reviewed also are studies of the risk factors associated with HIV infection among female sex workers, such as drug use, sexual behaviour, the presence of sexually transmitted diseases, and condom use; in addition, we comment on some studies of the clients of sex workers. Finally, we propose directions that future research in this area might take and discuss various interventions that need to be undertaken to reduce HIV transmission among female sex workers. PMID:8324860

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

    PubMed

    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.

  4. Sex Education: Another View

    ERIC Educational Resources Information Center

    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)

  5. Phosphazene additives

    DOEpatents

    Harrup, Mason K; Rollins, Harry W

    2013-11-26

    An additive comprising a phosphazene compound that has at least two reactive functional groups and at least one capping functional group bonded to phosphorus atoms of the phosphazene compound. One of the at least two reactive functional groups is configured to react with cellulose and the other of the at least two reactive functional groups is configured to react with a resin, such as an amine resin of a polycarboxylic acid resin. The at least one capping functional group is selected from the group consisting of a short chain ether group, an alkoxy group, or an aryloxy group. Also disclosed are an additive-resin admixture, a method of treating a wood product, and a wood product.

  6. Potlining Additives

    SciTech Connect

    Rudolf Keller

    2004-08-10

    In this project, a concept to improve the performance of aluminum production cells by introducing potlining additives was examined and tested. Boron oxide was added to cathode blocks, and titanium was dissolved in the metal pool; this resulted in the formation of titanium diboride and caused the molten aluminum to wet the carbonaceous cathode surface. Such wetting reportedly leads to operational improvements and extended cell life. In addition, boron oxide suppresses cyanide formation. This final report presents and discusses the results of this project. Substantial economic benefits for the practical implementation of the technology are projected, especially for modern cells with graphitized blocks. For example, with an energy savings of about 5% and an increase in pot life from 1500 to 2500 days, a cost savings of $ 0.023 per pound of aluminum produced is projected for a 200 kA pot.

  7. Sex differences in the HPA axis.

    PubMed

    Goel, Nirupa; Workman, Joanna L; Lee, Tiffany T; Innala, Leyla; Viau, Victor

    2014-07-01

    The hypothalamic-pituitary-adrenal (HPA) axis is a major component of the systems that respond to stress, by coordinating the neuroendocrine and autonomic responses. Tightly controlled regulation of HPA responses is critical for maintaining mental and physical health, as hyper- and hypo-activity have been linked to disease states. A long history of research has revealed sex differences in numerous components of the HPA stress system and its responses, which may partially form the basis for sex disparities in disease development. Despite this, many studies use male subjects exclusively, while fewer reports involve females or provide direct sex comparisons. The purpose of this article is to present sex comparisons in the functional and molecular aspects of the HPA axis, through various phases of activity, including basal, acute stress, and chronic stress conditions. The HPA axis in females initiates more rapidly and produces a greater output of stress hormones. This review focuses on the interactions between the gonadal hormone system and the HPA axis as the key mediators of these sex differences, whereby androgens increase and estrogens decrease HPA activity in adulthood. In addition to the effects of gonadal hormones on the adult response, morphological impacts of hormone exposure during development are also involved in mediating sex differences. Additional systems impinging on the HPA axis that contribute to sex differences include the monoamine neurotransmitters norepinephrine and serotonin. Diverse signals originating from the brain and periphery are integrated to determine the level of HPA axis activity, and these signals are, in many cases, sex-specific.

  8. Sex Education. Chapter Seventeen.

    ERIC Educational Resources Information Center

    Caster, Jerry A.

    Information and a framework that permits teachers to plan and initiate a successful sex education program for students with mental disabilities is provided. A major aspect of sex education should be its focus on social relationships, emotions, choice-making, and responsibilities to self and others. Sex education should not be viewed as a…

  9. Zebrafish sex: a complicated affair

    PubMed Central

    Liew, Woei Chang

    2014-01-01

    In this review, we provide a detailed overview of studies on the elusive sex determination (SD) and gonad differentiation mechanisms of zebrafish (Danio rerio). We show that the data obtained from most studies are compatible with polygenic sex determination (PSD), where the decision is made by the allelic combinations of several loci. These loci are typically dispersed throughout the genome, but in some teleost species a few of them might be located on a preferential pair of (sex) chromosomes. The PSD system has a much higher level of variation of SD genotypes both at the level of gametes and the sexual genotype of individuals, than that of the chromosomal sex determination systems. The early sexual development of zebrafish males is a complicated process, as they first develop a ‘juvenile ovary’, that later undergoes a transformation to give way to a testis. To date, three major developmental pathways were shown to be involved with gonad differentiation through the modulation of programmed cell death. In our opinion, there are more pathways participating in the regulation of zebrafish gonad differentiation/transformation. Introduction of additional powerful large-scale genomic approaches into the analysis of zebrafish reproduction will result in further deepening of our knowledge as well as identification of additional pathways and genes associated with these processes in the near future. PMID:24148942

  10. Sexing young snowy owls

    USGS Publications Warehouse

    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.

  11. Osho - Insights on sex

    PubMed Central

    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. PMID:23858266

  12. Model underpinning treatment for sex offenders with mild intellectual disability: current theories of sex offending.

    PubMed

    Lindsay, William R

    2005-12-01

    Although many writers have provided a theoretical framework for treatment of mainstream sex offenders, this research has not been extended to sex offenders with mild intellectual disability. My purpose here is to bring together several research strands to provide a theoretical model for working in this field, including theories of sex offending, developmental theories for offending, and work on quality of life. In addition to dealing with issues of sex offending, researchers should also investigate developmental and societal issues crucial in the genesis of sex offending and offending in general. Because societal issues are also important for treatment, engagement and identification with society are suggested. Quality of life and issues directly related to sex offending are of central importance. PMID:16266211

  13. Sex, epilepsy, and epigenetics.

    PubMed

    Qureshi, Irfan A; Mehler, Mark F

    2014-12-01

    Epilepsy refers to a heterogeneous group of disorders that are associated with a wide range of pathogenic mechanisms, seizure manifestations, comorbidity profiles, and therapeutic responses. These characteristics are all influenced quite significantly by sex. As with other conditions exhibiting such patterns, sex differences in epilepsy are thought to arise-at the most fundamental level-from the "organizational" and "activational" effects of sex hormones as well as from the direct actions of the sex chromosomes. However, our understanding of the specific molecular, cellular, and network level processes responsible for mediating sex differences in epilepsy remains limited. Because increasing evidence suggests that epigenetic mechanisms are involved both in epilepsy and in brain sexual dimorphism, we make the case here that analyzing epigenetic regulation will provide novel insights into the basis for sex differences in epilepsy.

  14. Sex Differences in Lifespan.

    PubMed

    Austad, Steven N; Fischer, Kathleen E

    2016-06-14

    Sex differences in longevity can provide insights into novel mechanisms of aging, yet they have been little studied. Surprisingly, sex-specific longevity patterns are best known in wild animals. Evolutionary hypotheses accounting for longevity patterns in natural populations include differential vulnerability to environmental hazards, differential intensity of sexual selection, and distinct patterns of parental care. Mechanistic hypotheses focus on hormones, asymmetric inheritance of sex chromosomes and mitochondria. Virtually all intensively studied species show conditional sex differences in longevity. Humans are the only species in which one sex is known to have a ubiquitous survival advantage. Paradoxically, although women live longer, they suffer greater morbidity particularly late in life. This mortality-morbidity paradox may be a consequence of greater connective tissue responsiveness to sex hormones in women. Human females' longevity advantage may result from hormonal influences on inflammatory and immunological responses, or greater resistance to oxidative damage; current support for these mechanisms is weak. PMID:27304504

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

    PubMed

    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.

  16. Sex tourism in Thailand.

    PubMed

    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.

  17. Sex tourism in Thailand.

    PubMed

    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. PMID:12286018

  18. Current Views on Sex Education

    ERIC Educational Resources Information Center

    Hoch, Loren L.

    1970-01-01

    Encourages the use of sex education in the schools and reviews the literature related to these issues: problems in implementation of sex education, reasons for sex education, comparison of sex education and attitudes in the United States with Sweden, communication with youth about sex, planning a program, and inhibitions on research. Thirty-five…

  19. Sex Discrimination in Coaching.

    ERIC Educational Resources Information Center

    Dessem, Lawrence

    1980-01-01

    Even in situations in which the underpayment of girls' coaches is due to the sex of the students coached rather than to the sex of the coaches, the coaches and the girls coached are victims of unlawful discrimination. Available from Harvard Women's Law Journal, Harvard Law School, Cambridge, MA 02138. (Author/IRT)

  20. Sex Equity Coordinator's Handbook.

    ERIC Educational Resources Information Center

    Rubenstein, Dorothy; Sillman, Donna

    This guidebook was designed to assist sex equity coordinators in the Los Angeles Community College District in promoting the recruitment, retention, and placement of students in vocational programs that are non-traditional for their sex. The guidebook's first ten chapters present: (1) outlines of relevant legislation and legal guidelines for…

  1. Sex Education Materials.

    ERIC Educational Resources Information Center

    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…

  2. Sex and America's Teenagers.

    ERIC Educational Resources Information Center

    Alan Guttmacher Inst., New York, NY.

    Although sexual activity is common among teenagers, it is not as widespread, and does not begin as early, as most adults believe. This report provides detailed data and analysis of sex among adolescents. Adolescent sexual activity is grouped in ten categories: (1) Rites of passage; (2) The context of adolescents' lives; (3) Sex among teenagers;…

  3. Sex Away from Home

    ERIC Educational Resources Information Center

    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)

  4. TA and Sex Stereotypes

    ERIC Educational Resources Information Center

    Roney, Anne M.

    1975-01-01

    Author discusses sex stereotypes and how they relate to transactional analysis. Thus, she claims there are striking similarities between female and male stereotypes and the Child and Adult respectively. Sex stereotypes hinder the attaining of the "I'm O.K. You're O.K." state between males and females. (SE)

  5. Single-Sex Classrooms

    ERIC Educational Resources Information Center

    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…

  6. Sex in the flesh.

    PubMed

    Laqueur, Thomas W

    2003-06-01

    This response to Michael Stolberg argues that the occasional piece of evidence for sexual dimorphism in Renaissance anatomy does no damage to what I had earlier called the "one-sex model." There are three reasons for this: a considerable amount of such evidence had long been available; stray observations do not discredit worldviews; and new supporting evidence for the one-sex model was also available. Moreover, illustrations in the purportedly paradigm-altering texts in fact support the old model. Since there was no radical change during the sixteenth and seventeenth centuries, the reasons offered by Stolberg for why it happened then are moot. The view that biology grounded two sexes (the two-sex model) replaced the view that it reflected imperfectly an underlying metaphysical truth (the one-sex model) as part of the epistemological revolution of the Enlightenment. PMID:12879559

  7. Sex in Fungi

    PubMed Central

    Ni, Min; Feretzaki, Marianna; Sun, Sheng; Wang, Xuying; Heitman, Joseph

    2012-01-01

    Sexual reproduction enables genetic exchange in eukaryotic organisms as diverse as fungi, animals, plants, and ciliates. Given its ubiquity, sex is thought to have evolved once, possibly concomitant with or shortly after the origin of eukaryotic organisms themselves. The basic principles of sex are conserved, including ploidy changes, the formation of gametes via meiosis, mate recognition, and cell-cell fusion leading to the production of a zygote. Although the basic tenants are shared, sex determination and sexual reproduction occur in myriad forms throughout nature, including outbreeding systems with more than two mating types or sexes, unisexual selfing, and even examples in which organisms switch mating type. As robust and diverse genetic models, fungi provide insights into the molecular nature of sex, sexual specification, and evolution to advance our understanding of sexual reproduction and its impact throughout the eukaryotic tree of life. PMID:21942368

  8. The many faces of sex work

    PubMed Central

    Harcourt, C; Donovan, B

    2005-01-01

    Objective: To compile a global typography of commercial sex work. Methods: A Medline search and review of 681 "prostitution" articles was conducted. In addition, the investigators pooled their 20 years of collected papers and monographs, and their observations in more than 15 countries. Arbitrary categories were developed to compile a workable typology of sex work. Results: At least 25 types of sex work were identified according to worksite, principal mode of soliciting clients, or sexual practices. These types of work are often grouped under the headings of "direct" and "indirect" prostitution, with the latter group less likely to be perceived or to perceive themselves as sex workers. In general, policing sex work can change its typology and location but its prevalence is rarely affected. The public health implications of sex work vary widely. Conclusion: Developing comprehensive sexual health promotion programmes requires a complete understanding of the types of sex work in a particular area. This study provides a checklist for developing appropriate and targeted programmes. PMID:15923285

  9. Does sex-ratio selection influence nest-site choice in a reptile with temperature-dependent sex determination?

    PubMed Central

    Mitchell, Timothy S.; Maciel, Jessica A.; Janzen, Fredric J.

    2013-01-01

    Evolutionary theory predicts that dioecious species should produce a balanced primary sex ratio maintained by frequency-dependent selection. Organisms with environmental sex determination, however, are vulnerable to maladaptive sex ratios, because environmental conditions vary spatio-temporally. For reptiles with temperature-dependent sex determination, nest-site choice is a behavioural maternal effect that could respond to sex-ratio selection, as mothers could adjust offspring sex ratios by choosing nest sites that will have particular thermal properties. This theoretical prediction has generated decades of empirical research, yet convincing evidence that sex-ratio selection is influencing nesting behaviours remains absent. Here, we provide the first experimental evidence from nature that sex-ratio selection, rather than only viability selection, is probably an important component of nest-site choice in a reptile with temperature-dependent sex determination. We compare painted turtle (Chrysemys picta) neonates from maternally selected nest sites with those from randomly selected nest sites, observing no substantive difference in hatching success or survival, but finding a profound difference in offspring sex ratio in the direction expected based on historical records. Additionally, we leverage long-term data to reconstruct our sex ratio results had the experiment been repeated in multiple years. As predicted by theory, our results suggest that sex-ratio selection has shaped nesting behaviour in ways likely to enhance maternal fitness. PMID:24266033

  10. Sex and Fertility After SCI

    MedlinePlus

    ... About Blog Facing Disability Jeff Shannon Donate Experts \\ Sex and Fertility After Spinal Cord Injury Topics Adult ... Spasticity, Physical Therapy-Lokomat Spasticity, Physical Therapy-Lokomat Sex and Fertility After Spinal Cord Injury Sex and ...

  11. Hepatitis C: Sex and Sexuality

    MedlinePlus

    ... 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 ...

  12. Uterine tumors resembling ovarian sex cord tumors are polyphenotypic neoplasms with true sex cord differentiation.

    PubMed

    Irving, Julie A; Carinelli, Silvestro; Prat, Jaime

    2006-01-01

    In this study, we present the clinicopathologic features and immunophenotypic characteristics of five cases of uterine tumors resembling ovarian sex cord tumors and three cases of endometrial stromal tumors with sex cord-like elements, with emphasis on immunohistochemical markers of sex cord differentiation. The mean patient age was 42 years (range 19-69 years), and vaginal bleeding was the most common clinical presentation. The tumors were usually polypoid masses arising in the uterine fundus, with a mean tumor size of 6.7 cm. Sex cord patterns in uterine tumors resembling ovarian sex cord tumors, including anastomosing cords, trabeculae, small nests, tubules, and in one case, a striking retiform architecture with Leydig-like cells, comprised from 70 to 100% of the tumor volume. All uterine tumors resembling ovarian sex cord tumors were positive for two or more markers of sex cord differentiation; all five cases showed strong immunoreactivity for calretinin, with coexpression of CD99 (four cases), Melan-A (two cases), and inhibin (two cases). Endometrial stromal tumors with sex cord-like elements were less frequently positive for markers of sex cord differentiation, with each case positive for one marker (calretinin, two cases; CD99, one case). In addition, all eight cases were frequently positive for cytokeratin, CD10, vimentin, estrogen receptor, and progesterone receptor; desmin immunoreactivity, when present, was limited to minor foci of smooth muscle. Overall, the morphologic and immunohistochemical findings in uterine tumors resembling ovarian sex cord tumors strongly support that these unusual uterine tumors are polyphenotypic neoplasms with true sex cord differentiation.

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

    PubMed Central

    Ditlecadet, Delphine; Martin, Luc J.; Lanctot, Richard B.; Lecomte, Nicolas

    2016-01-01

    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. PMID:27168992

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

    PubMed

    Giroux, Marie-Andrée; Ditlecadet, Delphine; Martin, Luc J; Lanctot, Richard B; Lecomte, Nicolas

    2016-01-01

    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. PMID:27168992

  15. Juvenile Sex Offenders.

    PubMed

    Ryan, Eileen P

    2016-01-01

    Public policy has tended to treat juvenile sex offenders (JSOs) as adult sex offenders in waiting, despite research that contradicts this notion. Although as a group, JSOs are more similar to general delinquents than to adult sex offenders, atypical sexual interests and sexual victimization during childhood may be a pathway for sexual offending that differentiates some JSOs from their nonsexually delinquent peers. Developmental considerations must be considered in risk assessment evaluations of these youth. This article reviews theories of sexual offending in youth, risk factors for juvenile offending and reoffending, psychopathology in JSOs, risk assessment, and treatment. PMID:26593121

  16. Beliefs About Sex and Parent-Child-Church Sex Communication Among Church-Based African American Youth.

    PubMed

    Moore, Erin; Berkley-Patton, Jannette; Bohn, Alexandria; Hawes, Starlyn; Bowe-Thompson, Carole

    2015-10-01

    Parent-child sex communication has been shown to be protective against sexual risk among African American youth. The current study sought to use the theory of planned behavior as a framework for focus group discussions (N = 54 youth participants aged 12-19 years) to explore church youths' (a) sex beliefs and values (attitudes), (b) sources and evaluation of sex communication and education (subjective norms), (c) facilitator/barriers to adolescent sexual risk reduction and communication behaviors (perceived behavioral control), and (d) intentions to engage in these behaviors. Additionally, participants identified strategies for consideration in developing tailored parent-child-church sex communication education programs for use in African American churches. Themes suggested both positive and negative attitudes toward premarital sex and parents and churches as key sources of sex education and communication. Strategies to enhance parent-child-church sex communication are discussed in the context of these findings.

  17. Sex investment ratios in eusocial Hymenoptera support inclusive fitness theory.

    PubMed

    Bourke, A F G

    2015-11-01

    Inclusive fitness theory predicts that sex investment ratios in eusocial Hymenoptera are a function of the relatedness asymmetry (relative relatedness to females and males) of the individuals controlling sex allocation. In monogynous ants (with one queen per colony), assuming worker control, the theory therefore predicts female-biased sex investment ratios, as found in natural populations. Recently, E.O. Wilson and M.A. Nowak criticized this explanation and presented an alternative hypothesis. The Wilson-Nowak sex ratio hypothesis proposes that, in monogynous ants, there is selection for a 1 : 1 numerical sex ratio to avoid males remaining unmated, which, given queens exceed males in size, results in a female-biased sex investment ratio. The hypothesis also asserts that, contrary to inclusive fitness theory, queens not workers control sex allocation and queen-worker conflict over sex allocation is absent. Here, I argue that the Wilson-Nowak sex ratio hypothesis is flawed because it contradicts Fisher's sex ratio theory, which shows that selection on sex ratio does not maximize the number of mated offspring and that the sex ratio proposed by the hypothesis is not an equilibrium for the queen. In addition, the hypothesis is not supported by empirical evidence, as it fails to explain 'split' (bimodal) sex ratios or data showing queen and worker control and ongoing queen-worker conflict. By contrast, these phenomena match predictions of inclusive fitness theory. Hence, the Wilson-Nowak sex ratio hypothesis fails both as an alternative hypothesis for sex investment ratios in eusocial Hymenoptera and as a critique of inclusive fitness theory.

  18. Sex investment ratios in eusocial Hymenoptera support inclusive fitness theory.

    PubMed

    Bourke, A F G

    2015-11-01

    Inclusive fitness theory predicts that sex investment ratios in eusocial Hymenoptera are a function of the relatedness asymmetry (relative relatedness to females and males) of the individuals controlling sex allocation. In monogynous ants (with one queen per colony), assuming worker control, the theory therefore predicts female-biased sex investment ratios, as found in natural populations. Recently, E.O. Wilson and M.A. Nowak criticized this explanation and presented an alternative hypothesis. The Wilson-Nowak sex ratio hypothesis proposes that, in monogynous ants, there is selection for a 1 : 1 numerical sex ratio to avoid males remaining unmated, which, given queens exceed males in size, results in a female-biased sex investment ratio. The hypothesis also asserts that, contrary to inclusive fitness theory, queens not workers control sex allocation and queen-worker conflict over sex allocation is absent. Here, I argue that the Wilson-Nowak sex ratio hypothesis is flawed because it contradicts Fisher's sex ratio theory, which shows that selection on sex ratio does not maximize the number of mated offspring and that the sex ratio proposed by the hypothesis is not an equilibrium for the queen. In addition, the hypothesis is not supported by empirical evidence, as it fails to explain 'split' (bimodal) sex ratios or data showing queen and worker control and ongoing queen-worker conflict. By contrast, these phenomena match predictions of inclusive fitness theory. Hence, the Wilson-Nowak sex ratio hypothesis fails both as an alternative hypothesis for sex investment ratios in eusocial Hymenoptera and as a critique of inclusive fitness theory. PMID:26238365

  19. Multiple Sex-Associated Regions and a Putative Sex Chromosome in Zebrafish Revealed by RAD Mapping and Population Genomics

    PubMed Central

    Anderson, Jennifer L.; Rodríguez Marí, Adriana; Braasch, Ingo; Amores, Angel; Hohenlohe, Paul; Batzel, Peter; Postlethwait, John H.

    2012-01-01

    Within vertebrates, major sex determining genes can differ among taxa and even within species. In zebrafish (Danio rerio), neither heteromorphic sex chromosomes nor single sex determination genes of large effect, like Sry in mammals, have yet been identified. Furthermore, environmental factors can influence zebrafish sex determination. Although progress has been made in understanding zebrafish gonad differentiation (e.g. the influence of germ cells on gonad fate), the primary genetic basis of zebrafish sex determination remains poorly understood. To identify genetic loci associated with sex, we analyzed F2 offspring of reciprocal crosses between Oregon *AB and Nadia (NA) wild-type zebrafish stocks. Genome-wide linkage analysis, using more than 5,000 sequence-based polymorphic restriction site associated (RAD-tag) markers and population genomic analysis of more than 30,000 single nucleotide polymorphisms in our *ABxNA crosses revealed a sex-associated locus on the end of the long arm of chr-4 for both cross families, and an additional locus in the middle of chr-3 in one cross family. Additional sequencing showed that two SNPs in dmrt1 previously suggested to be functional candidates for sex determination in a cross of ABxIndia wild-type zebrafish, are not associated with sex in our AB fish. Our data show that sex determination in zebrafish is polygenic and that different genes may influence sex determination in different strains or that different genes become more important under different environmental conditions. The association of the end of chr-4 with sex is remarkable because, unique in the karyotype, this chromosome arm shares features with known sex chromosomes: it is highly heterochromatic, repetitive, late replicating, and has reduced recombination. Our results reveal that chr-4 has functional and structural properties expected of a sex chromosome. PMID:22792396

  20. Sex-biased avian host use by arbovirus vectors

    PubMed Central

    Burkett-Cadena, Nathan D.; Bingham, Andrea M.; Unnasch, Thomas R.

    2014-01-01

    Prevalence of arthropod-borne parasites often differs drastically between host sexes. This sex-related disparity may be related to physiological (primarily hormonal) differences that facilitate or suppress replication of the pathogen in host tissues. Alternately, differences in pathogen prevalence between host sexes may be owing to differential exposure to infected vectors. Here, we report on the use of PCR-based assays recognizing bird sex chromosomes to investigate sex-related patterns of avian host use from field-collected female mosquitoes from Florida, USA. Mosquitoes took more bloodmeals from male birds (64.0% of 308 sexed samples) than female birds (36.0%), deviating significantly from a hypothetical 1:1 sex ratio. In addition, male-biased host use was consistent across mosquito species (Culex erraticus (64.4%); Culex nigripalpus (61.0%) and Culiseta melanura (64.9%)). Our findings support the hypothesis that sex-biased exposure to vector-borne pathogens contributes to disparities in parasite/pathogen prevalence between the sexes. While few studies have yet to investigate sex-biased host use by mosquitoes, the methods used here could be applied to a variety of mosquito-borne disease systems, including those that affect health of humans, domestic animals and wildlife. Understanding the mechanisms that drive sex-based disparities in host use may lead to novel strategies for interrupting pathogen/parasite transmission. PMID:26064562

  1. Sex-linked recessive

    MedlinePlus

    ... through families through one of the X or Y chromosomes. X and Y are sex chromosomes. Dominant inheritance ... that X chromosome will cause the disease. The Y chromosome is the other half of the XY gene ...

  2. Testicular Cancer and Sex

    MedlinePlus

    ... remove just one testicle, called an inguinal orchiectomy (IO), does not make a patient impotent and seldom ... everything from having sex the day after their IO (ouch!) all the way through having to go ...

  3. Juvenile Sex Offenders.

    PubMed

    Ryan, Eileen P; Otonichar, Joseph M

    2016-07-01

    Sexual offending by juveniles accounts for a sizable percentage of sexual offenses, especially against young children. In this article, recent research on female juvenile sex offenders (JSOs), risk factors for offending in juveniles, treatment, and the ways in which these youth may differ from general delinquents will be reviewed. Most JSOs do not go on to develop paraphilic disorders or to commit sex offenses during adulthood, and as a group, they are more similar to nonsexual offending juvenile delinquents than to adult sex offenders. Recent research has elucidated some differences between youth who commit sex offenses and general delinquents in the areas of atypical sexual interests, the use of pornography, and early sexual victimization during childhood. PMID:27222141

  4. Sex during Pregnancy

    MedlinePlus

    ... holding each other. You also may need to experiment with other positions for sex to find those ... as a safety precaution, because semen contains a chemical that may actually stimulate contractions. Check with your ...

  5. Sex-role and opposite-sex interpersonal attraction.

    PubMed

    Lombardo, J P; Francis, P L; Brown, S

    1988-12-01

    Androgynous, traditional, and undifferentiated male and female subjects indicated their attraction to three opposite-sex strangers who were described as having an androgynous, traditional, and undifferentiated sex-role. Subjects' ability to describe the sex-roles of the strangers was also measured. Androgynous strangers were most preferred, undifferentiated strangers least preferred. The least preferred undifferentiated strangers' sex-role was most accurately described. Subjects were least successful in describing the androgynous sex-role. PMID:3226838

  6. Morphometric sexing of Northwest Atlantic Roseate Terns

    USGS Publications Warehouse

    Palestis, Brian G.; Nisbet, Ian C.T.; Hatch, Jeremy J.; Szczys, Patricia; Spendelow, Jeffrey A.

    2012-01-01

    A difficulty in the study of monomorphic species is the inability of observers to visually distinguish females from males. Based on a sample of 745 known-sex birds nesting at Bird Island, MA, USA, a discriminant function analysis (DFA) was used to sex Roseate Terns (Sterna dougallii) of the Northwest Atlantic population using morphological measurements. DFA using only the total length of the head (including the bill) correctly identified the sex of approximately 86% of the terns, which increased to 88% if both members of a pair were measured. Including additional measurements increased these percentages slightly, to 87% and 90%, respectively. These levels of accuracy are generally higher than those reported for other species of terns. Because female-female pairs are frequent in this population, one cannot assume that the member of a pair with the larger head is a male, and additional discriminant functions were developed to help separate female-female from male-female pairs.

  7. Sex differences in anxiety and emotional behavior

    PubMed Central

    Donner, Nina C.; Lowry, Christopher A.

    2013-01-01

    Research has elucidated causal links between stress exposure and the development of anxiety disorders, but due to the limited use of female or sex-comparative animal models, little is known about the mechanisms underlying sex differences in those disorders. This is despite an overwhelming wealth of evidence from the clinical literature that the prevalence of anxiety disorders is about twice as high in women compared to men, in addition to gender differences in severity and treatment efficacy. We here review human gender differences in generalized anxiety disorder, panic disorder, posttraumatic stress disorder and anxiety-relevant biological functions, discuss the limitations of classic conflict anxiety tests to measure naturally occurring sex differences in anxiety-like behaviors, describe sex-dependent manifestation of anxiety states after gestational, neonatal, or adolescent stressors, and present animal models of chronic anxiety states induced by acute or chronic stressors during adulthood. Potential mechanisms underlying sex differences in stress-related anxiety states include emerging evidence supporting the existence of two anatomically and functionally distinct serotonergic circuits that are related to the modulation of conflict anxiety and panic-like anxiety, respectively. We discuss how these serotonergic circuits may be controlled by reproductive steroid hormone-dependent modulation of crfr1 and crfr2 expression in the midbrain dorsal raphe nucleus and by estrous stage-dependent alterations of γ-aminobutyric acid (GABAergic) neurotransmission in the periaqueductal gray, ultimately leading to sex differences in emotional behavior. PMID:23588380

  8. Sex Equity: Is It Feasible?

    ERIC Educational Resources Information Center

    Shocklee, Georgia

    This guide presents a model and plan to expedite implementation of sex equity in vocational education through the elimination of sex stereotyping and sex bias. Aimed at vocational education administrators, the guide is organized into the four steps of the plan. Step 1 provides a rationale for the decision to implement a model sex equity program,…

  9. Maladaptive sex ratio adjustment by a sex-changing shrimp in selective-fishing environments.

    PubMed

    Chiba, Susumu; Yoshino, Kenji; Kanaiwa, Minoru; Kawajiri, Toshifumi; Goshima, Seiji

    2013-05-01

    1. Selective harvesting is acknowledged as a serious concern in efforts to conserve wild animal populations. In fisheries, most studies have focused on gradual and directional changes in the life-history traits of target species. While such changes represent the ultimate response of harvested animals, it is also well known that the life history of target species plastically alters with harvesting. However, research on the adaptive significance of these types of condition-dependent changes has been limited. 2. We explored the adaptive significance of annual changes in the age at sex-change of the protandrous (male-first) hermaphroditic shrimp and examined how selective harvesting affects life-history variation, by conducting field observations across 13 years and a controlled laboratory experiment. In addition, we considered whether plastic responses by the shrimp would be favourable, negligible or negative with respect to the conservation of fishery resources. 3. The age at sex-change and the population structure of the shrimp fluctuated between years during the study period. The results of the field observations and laboratory experiment both indicated that the shrimp could plastically change the timing of sex-change in accordance with the age structure of the population. These findings provide the first concrete evidence of adult sex ratio adjustment by pandalid shrimp, a group that has been treated as a model in the sex allocation theory. 4. The sex ratio adjustment by the shrimp did not always seem to be sufficient, however, as the supplement of females is restricted by their annual somatic growth rate. In addition, adjusted sex ratios are further skewed by the unintentional female-selectivity of fishing activity prior to the breeding season, indicating that the occurrence of males that have postponed sex-change causes sex ratio adjustment to become unfavourable. 5. We conclude that the plastic responses of harvested animals in selective fishing environments

  10. Sex determination in mythology and history.

    PubMed

    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.

  11. Sex hormones and adult hippocampal neurogenesis: Regulation, implications, and potential mechanisms.

    PubMed

    Mahmoud, Rand; Wainwright, Steven R; Galea, Liisa A M

    2016-04-01

    Neurogenesis within the adult hippocampus is modulated by endogenous and exogenous factors. Here, we review the role of sex hormones in the regulation of adult hippocampal neurogenesis in males and females. The review is framed around the potential functional implications of sex hormone regulation of adult hippocampal neurogenesis, with a focus on cognitive function and mood regulation, which may be related to sex differences in incidence and severity of dementia and depression. We present findings from preclinical studies of endogenous fluctuations in sex hormones relating to reproductive function and ageing, and from studies of exogenous hormone manipulations. In addition, we discuss the modulating roles of sex, age, and reproductive history on the relationship between sex hormones and neurogenesis. Because sex hormones have diverse targets in the central nervous system, we overview potential mechanisms through which sex hormones may influence hippocampal neurogenesis. Lastly, we advocate for a more systematic consideration of sex and sex hormones in studying the functional implications of adult hippocampal neurogenesis.

  12. AIDS and sex tourism.

    PubMed

    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.

  13. AIDS and sex tourism.

    PubMed

    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. PMID

  14. What Asexuality Contributes to the Same-Sex Marriage Discussion.

    PubMed

    Scherrer, Kristin S

    2010-01-01

    While same-sex marriage debates have captured public attention, it is but one component of a broader discussion regarding the role of marriage in a changing society. To inform this discussion, I draw on qualitative, Internet survey data from 102 self-identified asexual individuals. I find that asexual relationships are complicated and nuanced in ways that have implications for a GLBTQ political agenda, including same-sex marriage recognition. In addition, findings indicate that assumptions of sex and sexuality in relationships are problematic and that present language for describing relationships is limiting. Findings suggest a social justice agenda for marginalized sexualities should be broader in scope than same-sex marriage.

  15. Sex guilt and life satisfaction in Iranian-american women.

    PubMed

    Abdolsalehi-Najafi, Emon; Beckman, Linda J

    2013-08-01

    Although the experience of sex guilt has been considered among a variety of ethnic groups, the area has not yet been empirically explored among Iranian American women. The present study investigated the relationship between sexual self-schema (i.e., beliefs about the sexual aspects of oneself), acculturation, and sex guilt, and it further examined the association between sex guilt and life satisfaction in Iranian American women. A total of 65 Iranian American women, with a mean age of 31.3 years (SD = 11.7), completed five self-administered questionnaires. Findings indicated a significant inverse correlation between sexual self-schema and sex guilt. More specifically, women who endorsed negative self-views regarding their sexual self reported higher levels sex guilt. Results revealed that acculturation was unrelated to sex guilt, when the effect of being Muslim or non-Muslim was controlled. Women with high sex guilt reported significantly lower levels of life satisfaction. Moreover, analyses for mediation effects supported sex guilt as a partially mediating variable between sexual self-schema and life satisfaction. Levels of sex guilt were higher among Muslim women when compared to women of other religious affiliations. Additionally, Muslim women appeared to be significantly less acculturated to Western ideals than other religious groups. The present findings suggest that mental health professionals who provide services to Iranian American women need to consider the negative effects of sex guilt, particularly among Muslim women.

  16. Temperature sex reversal implies sex gene dosage in a reptile.

    PubMed

    Quinn, Alexander E; Georges, Arthur; Sarre, Stephen D; Guarino, Fiorenzo; Ezaz, Tariq; Graves, Jennifer A Marshall

    2007-04-20

    Sex in reptiles is determined by genes on sex chromosomes or by incubation temperature. Previously these two modes were thought to be distinct, yet we show that high incubation temperatures reverse genotypic males (ZZ) to phenotypic females in a lizard with ZZ and ZW sex chromosomes. Thus, the W chromosome is not necessary for female differentiation. Sex determination is probably via a dosage-sensitive male-determining gene on the Z chromosome that is inactivated by extreme temperatures. Our data invite a novel hypothesis for the evolution of temperature-dependent sex determination (TSD) and suggest that sex chromosomes may exist in many TSD reptiles.

  17. How Sex Attitudes Develop

    ERIC Educational Resources Information Center

    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.

  18. Sex and Cognition.

    ERIC Educational Resources Information Center

    Kimura, Doreen

    This book describes the major differences between men and women in cognitive or problem-solving abilities and discusses the possible biological contributions to such differences. The book argues that sex differences in cognitive patterns and in motor skills arose out of complementary evolutionary histories of men and women and that evidence for…

  19. Sex and deleterious mutations.

    PubMed

    Gordo, Isabel; Campos, Paulo R A

    2008-05-01

    The evolutionary advantage of sexual reproduction has been considered as one of the most pressing questions in evolutionary biology. While a pluralistic view of the evolution of sex and recombination has been suggested by some, here we take a simpler view and try to quantify the conditions under which sex can evolve given a set of minimal assumptions. Since real populations are finite and also subject to recurrent deleterious mutations, this minimal model should apply generally to all populations. We show that the maximum advantage of recombination occurs for an intermediate value of the deleterious effect of mutations. Furthermore we show that the conditions under which the biggest advantage of sex is achieved are those that produce the fastest fitness decline in the corresponding asexual population and are therefore the conditions for which Muller's ratchet has the strongest effect. We also show that the selective advantage of a modifier of the recombination rate depends on its strength. The quantification of the range of selective effects that favors recombination then leads us to suggest that, if in stressful environments the effect of deleterious mutations is enhanced, a connection between sex and stress could be expected, as it is found in several species.

  20. Sex, Courtship, and Marriage.

    ERIC Educational Resources Information Center

    Seiferth, Berniece

    The author presents an historical perspective on abortion, contraception and marriage as a prelude to an examination of changing attitudes toward sex. The article deals with the negative effects attributed to the increased incidence of early dating and early marriage of teenagers in the United States. The author also assumes positions on such…

  1. Sex And People.

    ERIC Educational Resources Information Center

    Jones, Kenneth L.; And Others

    This textbook for the college student emphasizes human sexuality as a part of the whole human life experience and contains a balance of biological, psychological, and sociological material. In 16 chapters the following topics are covered: (1) sex and society; (2) historical and cultural perspectives; (3) glandular control of sexual physiology; (4)…

  2. Sex Education and Ideals

    ERIC Educational Resources Information Center

    de Ruyter, Doret J.; Spiecker, Ben

    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 strict sense are rightfully called sexual…

  3. Sex, Technology and Morality.

    ERIC Educational Resources Information Center

    Case, Verna; And Others

    1986-01-01

    Provides an overview of the course "Sex, Technology, and Morality" which focuses on the human reproductive process and examines the advances in reproductive technology. The course emphasizes the social, political, and ethical implications of actual and possible technologies associated with human reproduction. (ML)

  4. Sex Education For Educators

    ERIC Educational Resources Information Center

    Renshaw, Domeena C.

    1973-01-01

    Currently, sex education covers the mechanics of reproduction; details of venereal disease, and birth control information. This paper argues that this field should be augmented by the inclusion of the emotionally enriching, interpersonal, and sociocultural elements of human sexuality. A fundamentally Freudian sketch of sexual development is…

  5. Sex Therapy and Mastectomy

    ERIC Educational Resources Information Center

    Witkin, Mildred Hope

    1975-01-01

    Because the emotional trauma associated with a mastectomy exceeds the physical trauma, the recovery of the woman is greatly affected by the response of her husband or lover. Sex therapy, therefore, involves the couple. The approach described is aimed at assisting the couple to confront and integrate the mastectomy experience. (Author)

  6. Sex Differences in Influenceability

    ERIC Educational Resources Information Center

    Eagly, Alice H.

    1978-01-01

    Examines the hypothesis that women are more easily influenced than men by reviewing the literature on persuasion and conformity research. Persuasion research and conformity studies not involving group pressure show scant empirical support for sex differences. For group pressure conformity research, a substantial minority of studies support the…

  7. Sex education in Cyprus.

    PubMed

    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

  8. Sunitinib Possible Sex-Divergent Therapeutic Outcomes.

    PubMed

    Segarra, Ignacio; Modamio, Pilar; Fernández, Cecilia; Mariño, Eduardo L

    2016-10-01

    Sunitinib is a tyrosine kinase inhibitor used for the treatment of renal cell carcinoma and metastatic brain tumors. Preclinical pharmacokinetic studies have shown higher sunitinib hepatic and brain exposure in female mice and higher sunitinib kidney concentrations in male mice. We explored whether sex-divergent tissue pharmacokinetics may anticipate sex-divergent therapeutic and toxicology responses in male and female patients. The review of the available scientific literature identified case reports, case series reports, clinical trials, and other studies associating sex with sunitinib outcomes. The results suggest male patients may respond better to renal cell carcinoma treatment and female patients may have better brain tumor treatment outcomes but a higher incidence of adverse events. Although more high-quality evidence is needed, these results, as anticipated by the preclinical data, may indicate possible sunitinib sex-divergent therapeutic outcomes in patients. In addition, we propose the systematic analysis of sex-based outcomes in clinical trial reports and their inclusion and review in the ethics committees and review boards to prevent, amongst others, patient burden in upcoming clinical trials. PMID:27318944

  9. Sex hormones and brain dopamine functions.

    PubMed

    Sotomayor-Zarate, Ramon; Cruz, Gonzalo; Renard, Georgina M; Espinosa, Pedro; Ramirez, Victor D

    2014-01-01

    Sex hormones exert differential effects on a variety of sensitive tissues like the reproductive tract, gonads, liver, bone and adipose tissue, among others. In the brain, sex hormones act as neuroactive steroids regulating the function of neuroendocrine diencephalic structures like the hypothalamus. In addition, steroids can exert physiological effects upon cortical, limbic and midbrain structures, influencing different behaviors such as memory, learning, mood and reward. In the last three decades, the role of sex hormones on monoamine neurotransmitters in extra-hypothalamic areas related to motivated behaviors, learning and locomotion has been the focus of much research. The purpose of this thematic issue is to present the state of art concerning the effects of sex hormones on the neurochemical regulation of dopaminergic midbrain areas involved in neurobiological and pathological processes, such as addiction to drugs of abuse. We also discuss evidence of how neonatal exposure to sex hormones or endocrine disrupting chemicals can produce long-term changes on the neurochemical regulation of dopaminergic neurons in the limbic and midbrain areas. PMID:25540983

  10. Sex education in France.

    PubMed

    Gallard, C

    1991-05-01

    The French Family Planning Movement (MFPF) has actively been involved in sex education within schools. In 1989, more than 1500 presentations were made to 23,000 pupils. Another activity is monitoring the application of statutes and regulations, for abortion, contraception, and sex education, and fighting to save and advance the rights of sexuality experts. Because of MFPF prominence in serious risks such as AIDs, sexual abuse, and rape, credibility has been enhanced. MFPF serves as a vehicle to change attitudes on male/female relationships. The government has permitted involvement in the preparation of a teaching program dealing with sexual abuse. The dominant influence of the Catholic Church on education has been evident since 1807. Up to WWI, religious morality was dominant. With Freud's contributions to the importance of sexuality in individual life, there were questions raised and a call for change in values and customs. In 1967, the statute was passed which authorized contraception, and sex education became an important issue. In 1973, Fontanet as Minister of Education outlined the recommendation for sex information and education in schools, including reproduction. Further official supportive recommendations were not made until 1985 when life education was entered into the primary syllabus. There was no provision even for teacher training; hence a wide variability in skills, commitment, and attitudes prevailed. MFPF reflects a position on tolerance in listening to others, expression and analysis of differences and critical thinking, identifying difficulties in talking about sex with respect to cultural and religious diversity, and help for the young in learning about their bodies, expressing feelings, and taking charge of emotions.

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

    ERIC Educational Resources Information Center

    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…

  12. Sex Role Attitudes and Sex Role Stereotyping: Recent Literature.

    ERIC Educational Resources Information Center

    New Jersey Research Bulletin, 1996

    1996-01-01

    This annotated bibliography profiles 17 publications examining sex role attitudes/sex role stereotyping from the perspectives of ethnicity, gender, and age. Cited in the section on ethnicity are studies of work satisfaction/family functioning among working-class Mexican-American women and cultural variations in sex typing by students in the United…

  13. Hypnotic Psychotherapy with Sex Offenders

    ERIC Educational Resources Information Center

    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.)

  14. Abnormal human sex chromosome constitutions

    SciTech Connect

    1993-12-31

    Chapter 22, discusses abnormal human sex chromosome constitution. Aneuploidy of X chromosomes with a female phenotype, sex chromosome aneuploidy with a male phenotype, and various abnormalities in X chromosome behavior are described. 31 refs., 2 figs.

  15. The ABCs of Sex Ed.

    ERIC Educational Resources Information Center

    Sroka, Stephen R.

    2002-01-01

    Cites statistics on extent of sexually transmitted diseases and pregnancies among adolescents; describes ideological dispute over how to teach sex education; advocates teaching the ABCs of sex education: Abstinence, Be Monogamous, and Condoms. (PKP)

  16. Sex Differences and Sex Steroids in Lung Health and Disease

    PubMed Central

    Townsend, Elizabeth A.; Miller, Virginia M.

    2012-01-01

    Sex differences in the biology of different organ systems and the influence of sex hormones in modulating health and disease are increasingly relevant in clinical and research areas. Although work has focused on sex differences and sex hormones in cardiovascular, musculoskeletal, and neuronal systems, there is now increasing clinical evidence for sex differences in incidence, morbidity, and mortality of lung diseases including allergic diseases (such as asthma), chronic obstructive pulmonary disease, pulmonary fibrosis, lung cancer, as well as pulmonary hypertension. Whether such differences are inherent and/or whether sex steroids play a role in modulating these differences is currently under investigation. The purpose of this review is to define sex differences in lung structure/function under normal and specific disease states, with exploration of whether and how sex hormone signaling mechanisms may explain these clinical observations. Focusing on adult age groups, the review addresses the following: 1) inherent sex differences in lung anatomy and physiology; 2) the importance of certain time points in life such as puberty, pregnancy, menopause, and aging; 3) expression and signaling of sex steroid receptors under normal vs. disease states; 4) potential interplay between different sex steroids; 5) the question of whether sex steroids are beneficial or detrimental to the lung; and 6) the potential use of sex steroid signaling as biomarkers and therapeutic avenues in lung diseases. The importance of focusing on sex differences and sex steroids in the lung lies in the increasing incidence of lung diseases in women and the need to address lung diseases across the life span. PMID:22240244

  17. ECOLOGICAL AND EVOLUTIONARY APPLICATIONS FOR ENVIRONMENTAL SEX REVERSAL OF FISH.

    PubMed

    Mcnair, Alistair; Lokman, P Mark; Closs, Gerard P; Nakagawa, Shinichi

    2015-03-01

    Environmental sex reversal (ESR), which results in a mismatch between genotypic and phenotypic sex, is well documented in numerous fish species and may be induced by chemical exposure. Historically, research involving piscine ESR has been carried out with a view to improving profitability in aquaculture or to elucidate the processes governing sex determination and sexual differentiation. However, recent studies in evolution and ecology suggest research on ESR now has much wider applications and ramifications. We begin with an overview of ESR in fish and a brief review of the traditional applications thereof. We then discuss ESR and its potential demographic consequences in wild populations. Theory even suggests sex-reversed fish may be purposefully released to manipulate population dynamics. We suggest new research directions that may prove fruitful in understanding how ESR at the individual level translates to population-level processes. In the latter portion of the review we focus on evolutionary applications of ESR. Sex-reversal studies from the aquaculture literature provide insight in to the evolvability of determinants of sexual phenotype. Additionally, induced sex reversal can provide information about the evolution of sex chromosomes and sex-linked traits. Recently, naturally occurring ESR has been implicated as a mechanism contributing to the evolution of sex chromosomes.

  18. Sex differences in learning processes of classical and operant conditioning.

    PubMed

    Dalla, Christina; Shors, Tracey J

    2009-05-25

    Males and females learn and remember differently at different times in their lives. These differences occur in most species, from invertebrates to humans. We review here sex differences as they occur in laboratory rodent species. We focus on classical and operant conditioning paradigms, including classical eyeblink conditioning, fear-conditioning, active avoidance and conditioned taste aversion. Sex differences have been reported during acquisition, retention and extinction in most of these paradigms. In general, females perform better than males in the classical eyeblink conditioning, in fear-potentiated startle and in most operant conditioning tasks, such as the active avoidance test. However, in the classical fear-conditioning paradigm, in certain lever-pressing paradigms and in the conditioned taste aversion, males outperform females or are more resistant to extinction. Most sex differences in conditioning are dependent on organizational effects of gonadal hormones during early development of the brain, in addition to modulation by activational effects during puberty and adulthood. Critically, sex differences in performance account for some of the reported effects on learning and these are discussed throughout the review. Because so many mental disorders are more prevalent in one sex than the other, it is important to consider sex differences in learning when applying animal models of learning for these disorders. Finally, we discuss how sex differences in learning continue to alter the brain throughout the lifespan. Thus, sex differences in learning are not only mediated by sex differences in the brain, but also contribute to them.

  19. The mechanisms underlying sexual differentiation of behavior and physiology in mammals and birds: relative contributions of sex steroids and sex chromosomes.

    PubMed

    Maekawa, Fumihiko; Tsukahara, Shinji; Kawashima, Takaharu; Nohara, Keiko; Ohki-Hamazaki, Hiroko

    2014-01-01

    From a classical viewpoint, sex-specific behavior and physiological functions as well as the brain structures of mammals such as rats and mice, have been thought to be influenced by perinatal sex steroids secreted by the gonads. Sex steroids have also been thought to affect the differentiation of the sex-typical behavior of a few members of the avian order Galliformes, including the Japanese quail and chickens, during their development in ovo. However, recent mammalian studies that focused on the artificial shuffling or knockout of the sex-determining gene, Sry, have revealed that sex chromosomal effects may be associated with particular types of sex-linked differences such as aggression levels, social interaction, and autoimmune diseases, independently of sex steroid-mediated effects. In addition, studies on naturally occurring, rare phenomena such as gynandromorphic birds and experimentally constructed chimeras in which the composition of sex chromosomes in the brain differs from that in the other parts of the body, indicated that sex chromosomes play certain direct roles in the sex-specific differentiation of the gonads and the brain. In this article, we review the relative contributions of sex steroids and sex chromosomes in the determination of brain functions related to sexual behavior and reproductive physiology in mammals and birds.

  20. Sexually selected sex differences in competitiveness explain sex differences in changes in drinking game participation.

    PubMed

    Hone, Liana S E; McCullough, Michael

    2015-01-01

    Drinking games are a risk factor for behavioral and health problems among university students. Previous cross-sectional research by Hone, Carter, and McCullough (2013) replicated well-established sex differences in drinking game behaviors (i.e., that men are more active drinking game participants than are women) and university drinking problems more generally. Hone et al. (2013) also found that these male-specific behavioral patterns are attributable in part to the fact that men's generally unrestricted sexual strategies, plus their social competitiveness, motivate them to participate in drinking games to display their fortitude and compete with same-sex rivals. Here, the authors conducted a study to evaluate with greater causal rigor whether sex differences in sexual restrictedness and social competitiveness-and sex differences in motivations for participating in drinking games in particular-are partially responsible for the sex differences in university students' drinking game behaviors and drinking problems. Sex differences in changes in frequency of drinking game participation were partially mediated by competitive motivations for participating in drinking games and by the effects of social competitiveness on competitive drinking game motivation. These findings lend additional support to the proposition that participation in drinking games is motivated in part by their suitability as a venue for sexual competition in university students' day-to-day lives. PMID:25974961

  1. Sex matters: evaluating sex and gender in migraine and headache research.

    PubMed

    Peterlin, B Lee; Gupta, Saurabh; Ward, Thomas N; Macgregor, Anne

    2011-06-01

    Significant sex differences exist in migraine and other headache disorders. Several hypotheses have been proposed to explain these differences, including fluctuations in sex hormones and receptor binding, genetic factors, differences in exposure to environmental stressors, as well as differences in response to stress and pain perception; but how valid are some of these findings and can we improve the quality of research in this field? It is notable that the preponderance of animal pain studies use male subjects to study a predominantly female disorder. Furthermore, with respect to headache and migraine sex differences, limited data have been derived from animal models. Additionally, although sex differences (based on the categorization of male vs female) may be more routinely evaluated in clinical headache research than in the basic science research, greater attention to potential differences across the life cycle of women (ie, premenopausal vs postmenopausal differences) and menstrual cycle is warranted. In this manuscript we define the differences between "sex" and "gender" and highlight the importance of their application and use in headache research. The enhanced recognition and implementation of attention to sex differences throughout the hormonal and life-cycle phase in both human and animal research will only help to strengthen and further our understanding of migraine and may help guide the direction of future headache research.

  2. Sex Education with Young Children.

    ERIC Educational Resources Information Center

    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…

  3. Sex Stereotyping Hurts All Kids.

    ERIC Educational Resources Information Center

    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)

  4. Single Sex Education. WEEA Digest.

    ERIC Educational Resources Information Center

    Pollard, Diane S.

    Title IX of the Educational Amendments of 1972 prohibits discrimination on the basis of sex in educational institutions that receive federal financial assistance. This digest focuses on the theme of single-sex education. Articles featured in this issue include: (1) "Single-Sex Education" (Diane S. Pollard); (2) "A Legal Framework for Single-Sex…

  5. Sex Stereotyping by Tomorrow's Executives.

    ERIC Educational Resources Information Center

    Kovach, Kenneth A.

    1985-01-01

    Describes a study in which 512 college seniors were surveyed to see if members of one sex would implicitly stereotype by sex to a greater degree than the other. Questions concerned job/home conflicts and selection and promotion. Results indicated that men and women are equally guilty of sex stereotyping, which works against women in the workplace.…

  6. Beyond the 'safe sex' propaganda.

    PubMed

    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.

  7. Beyond the 'safe sex' propaganda.

    PubMed

    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. PMID:21061922

  8. Sex Steroid Actions in Male Bone

    PubMed Central

    Laurent, Michaël R.; Claessens, Frank; Gielen, Evelien; Lagerquist, Marie K.; Vandenput, Liesbeth; Börjesson, Anna E.; Ohlsson, Claes

    2014-01-01

    Sex steroids are chief regulators of gender differences in the skeleton, and male gender is one of the strongest protective factors against osteoporotic fractures. This advantage in bone strength relies mainly on greater cortical bone expansion during pubertal peak bone mass acquisition and superior skeletal maintenance during aging. During both these phases, estrogens acting via estrogen receptor-α in osteoblast lineage cells are crucial for male cortical and trabecular bone, as evident from conditional genetic mouse models, epidemiological studies, rare genetic conditions, genome-wide meta-analyses, and recent interventional trials. Genetic mouse models have also demonstrated a direct role for androgens independent of aromatization on trabecular bone via the androgen receptor in osteoblasts and osteocytes, although the target cell for their key effects on periosteal bone formation remains elusive. Low serum estradiol predicts incident fractures, but the highest risk occurs in men with additionally low T and high SHBG. Still, the possible clinical utility of serum sex steroids for fracture prediction is unknown. It is likely that sex steroid actions on male bone metabolism rely also on extraskeletal mechanisms and cross talk with other signaling pathways. We propose that estrogens influence fracture risk in aging men via direct effects on bone, whereas androgens exert an additional antifracture effect mainly via extraskeletal parameters such as muscle mass and propensity to fall. Given the demographic trends of increased longevity and consequent rise of osteoporosis, an increased understanding of how sex steroids influence male bone health remains a high research priority. PMID:25202834

  9. Seeking sex partners through the internet and mobile phone applications among men who have sex with men in Taiwan.

    PubMed

    Ko, Nai-Ying; Tseng, Po-Chia; Huang, Yu-Chao; Chen, Yen-Chin; Hsu, Su-Ting

    2016-07-01

    It has become popular for men who have sex with men (MSM) to use mobile-phone geosocial networking applications (mobile apps) to find sex partners. A cross-sectional online survey was conducted in Taiwan to compare the sexual and substance-use behaviors of MSM seeking sex partners through the internet and mobile apps. Of the 1060 participants, 65.8% used the internet via computer and 37.7% used a mobile app to find sexual partners, while 30.3% used recreational drugs or alcohol in the previous 6 months. MSM who exclusively used mobile apps to seek sex partners were significantly more likely than MSM seeking sex via computer to be older, to have used recreational drugs or alcohol, and to have sex with HIV-positive partners. Additionally, using mobile apps to seek sex partners was significantly associated with having sex with online partners through either mobile apps or computer-based internet use (adjusted odds ratio (AOR), 7.12 [3.87-13.11]), self-reporting as HIV-positive (AOR, 2.24 [1.12-4.12]), using recreational drugs (AOR, 1.67 [1.21-2.32]), having disclosed HIV status to sexual partners (AOR, 1.44 [1.03-2.02]), and having sex with HIV-positive partners (AOR, 1.81 [1.06-3.10]). In conclusion, the mobile apps may serve as a feasible platform for HIV-positive MSM to find other HIV-positive partners.

  10. Sex ratio and spatial distribution of male and female Antennaria dioica (Asteraceae) plants

    NASA Astrophysics Data System (ADS)

    Varga, Sandra; Kytöviita, Minna-Maarit

    2011-09-01

    Sex ratio, sex spatial distribution and sexual dimorphism in reproduction and arbuscular mycorrhizal colonisation were investigated in the dioecious clonal plant Antennaria dioica (Asteraceae). Plants were monitored for five consecutive years in six study plots in Oulanka, northern Finland. Sex ratio, spatial distribution of sexes, flowering frequency, number of floral shoots and the number and weight of inflorescences were recorded. In addition, intensity of mycorrhizal fungi in the roots was assessed. Both sexes flowered each year with a similar frequency, but the overall genet sex ratio was strongly female-biased. The bivariate Ripley's analysis of the sex distribution showed that within most plots sexes were randomly distributed except for one plot. Sexual dimorphism was expressed as larger floral and inflorescence production and heavier inflorescences in males. In addition, the roots of both sexes were colonised to a similar extent by arbuscular mycorrhizal fungi. The female sex-biased flowering ratios reported are not consistent among years and cannot be explained in terms of spatial segregation of the sexes or sex lability. The possible reasons for the female-biased sex ratio are discussed.

  11. Child sex rings.

    PubMed

    Wild, N J; Wynne, J M

    1986-07-19

    Details of 11 child sex rings identified in one working class community were obtained by interviewing investigating police officers and examining health and social services records. The rings contained 14 adult male perpetrators and 175 children aged 6-15 years. Most perpetrators used child ringleaders to recruit victims; others became a "family friend" or obtained a position of authority over children. Secrecy was encouraged and bribery, threats, and peer pressure used to induce participation in sexual activities. Offences reported included fondling, masturbation, pornography, and oral, vaginal, and anal intercourse. Eleven perpetrators were successfully prosecuted; all but one received a sentence of three years or less. Behavioural problems were common among those children who had participated for a long time. Child sex rings are difficult to detect and may be common. Many children are seriously abused as a consequence of them. PMID:3730803

  12. Sex Hormones and Tendon.

    PubMed

    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, in active young female athletes, physiological high concentration of estrogen may enhance the risk of injuries due to reduced fibrillar crosslinking and enhanced joint laxity. In men, testosterone can enhance tendon stiffness due to an enhanced tendon collagen turnover and collagen content, but testosterone 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. PMID:27535256

  13. Abnormalities of sex differentiation.

    PubMed

    Nawata, H; Takayanagi, R; Yanase, T; Ikuyama, S; Okabe, T

    1996-01-01

    Sex differentiation is determined by a cascade of events proceeding from chromosomal sex to the completion of sexual maturation at puberty. Many factors involved in this cascade have been identified. Here we focus on DAX-1, androgen receptor and cytochrome P450c17, and discuss their functions in sex differentiation. We analyzed the DAX-1 genes of two unrelated Japanese patients with congenital adrenal hypoplasia and hypogonadotropic hypogonadism using PCR amplification of genomic DNA and complete exonic sequencing, and established that congenital adrenal hypoplasia and hypogonadotropic hypogonadism result from not only inherited but also de novo mutation in the DAX-1 gene. Androgen insensitivity syndrome (AIS) is a good model to clarify the relationship between the structure and function of androgen receptor, the androgen receptor gene mutation and clinical phenotype. We analyzed 15 cases of AIS and demonstrate the structural and functional relationships of the androgen receptor. We have sequenced the CYP17 (P450c17) gene in DNA from several patients with 17 alpha-hydroxylase deficiency, reconstructed the mutations in a human P450c17 cDNA and expressed the mutant P450c17 in COSl cells to characterize the kinetic properties of 17 alpha-hydroxylase and 17,20-lyase activities. The molecular bases of cases clinically reported as 17 alpha-hydroxylase deficiency have turned out to be complete or partial combined deficiencies of 17 alpha-hydroxylase/17,20-lyase. PMID:8864743

  14. The many costs of sex.

    PubMed

    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.

  15. Sex Differences in Constitutive Autophagy

    PubMed Central

    Oliván, Sara; Calvo, Ana Cristina; Manzano, Raquel; Zaragoza, Pilar

    2014-01-01

    Sex bias has been described nowadays in biomedical research on animal models, although sexual dimorphism has been confirmed widely under pathological and physiological conditions. The main objective of our work was to study the sex differences in constitutive autophagy in spinal cord and skeletal muscle tissue from wild type mice. To examine the influence of sex on autophagy, mRNA and proteins were extracted from male and female mice tissues. The expressions of microtubule-associated protein 1 light chain 3 (LC3) and sequestosome 1 (p62), markers to monitor autophagy, were analyzed at 40, 60, 90, and 120 days of age. We found significant sex differences in the expression of LC3 and p62 in both tissues at these ages. The results indicated that sex and tissue specific differences exist in constitutive autophagy. These data underlined the need to include both sexes in the experimental groups to minimize any sex bias. PMID:24719882

  16. Oral sex and oropharyngeal cancer

    PubMed Central

    Nguyen, Nam P.; Nguyen, Ly M.; Thomas, Sroka; Hong-Ly, Bevan; Chi, Alexander; Vos, Paul; Karlsson, Ulf; Vinh-Hung, Vincent

    2016-01-01

    Abstract Background: We aimed to study the prevalence of oral sex and its possible association with human papillomavirus (HPV) 16 infection in the development of oropharyngeal cancer in the US population for possible prevention. Methods: We conduct a systemic review on the prevalence of oral sex among Americans among different age groups, the prevalence of HPV 16 infection reported in oropharyngeal cancer, and correlation between oral sex and oropharyngeal cancer. Results: Oral sex is prevalent among adolescents and sexually active adults. Sixty percent of oropharyngeal cancer reported in the United States is associated with HPV 16 infections. Individuals who practiced oral sex with multiple partners are at risk for developing oropharyngeal cancer and need to be informed about practicing safe sex or getting vaccination. Conclusion: Family physicians will play a key role in prevention and educating the public about the risk of oral sex. PMID:27428229

  17. Physiological sex predicts hybrid sterility regardless of genotype.

    PubMed

    Malone, John H; Michalak, P

    2008-01-01

    Reproductive isolation between biological species is characterized by Haldane's rule, which states that the heterogametic sex (XY or ZW) suffers the most dysfunctional effects of hybridization. It has been hypothesized that, in addition to X-linked recessive genes, Haldane's rule also reflects the faster evolution of genes related to male reproduction (faster-male evolution). We used sex-reversed hybrid Xenopus to test faster-male evolution by examining the fertility of sex-reversed individuals with the genotype of the inverse phenotypic sex. Hybrid males are sterile and hybrid females are fertile irrespective of their genotypic sex. Gene expression profiles match these adult phenotypes, and our results demonstrate that faster-male evolution is the most likely mechanism producing hybrid male sterility.

  18. Secular trends and geographical variations in sex ratio at birth.

    PubMed

    Pavic, Dario

    2015-12-01

    Numerous studies have established the presence of secular trends and geographical variations in sex ratio at birth, albeit with mixed and often contradictory results. In addition, a multitude of environmental, social, economic, demographic and other factors has been proposed to influence the sex ratio at birth, thus complicating the interpretation of both secular trends and geographical variations. In this paper, the current state of knowledge on these issues is presented and critically assessed. Analyzing longer time series of sex ratio at birth with possible cycles and random components is given priority over establishing simple linear trends in the data. In analyzing the geographical variation in the sex ratio at birth, two different levels of analysis are distinguished (global and local), and two different sets of factors affecting the sex ratio at birth are proposed accordingly. Some key guidelines and future research directions are also proposed.

  19. Legal recognition of same-sex couples and family formation.

    PubMed

    Trandafir, Mircea

    2015-02-01

    It has long been debated how legalizing same-sex marriage would affect (different-sex) family formation. In this article, I use data on OECD member countries for the period 1980-2009 to examine the effects of the legal recognition of same-sex couples (through marriage or an alternative institution) on different-sex marriage, divorce, and extramarital births. Estimates from difference-in-difference models indicate that the introduction of same-sex marriage or of alternative institutions has no negative effects on family formation. These findings are robust to a multitude of specification checks, including the construction of counterfactuals using the synthetic control method. In addition, the country-by-country case studies provide evidence of homogeneity of the estimated effects. PMID:25573170

  20. Legal recognition of same-sex couples and family formation.

    PubMed

    Trandafir, Mircea

    2015-02-01

    It has long been debated how legalizing same-sex marriage would affect (different-sex) family formation. In this article, I use data on OECD member countries for the period 1980-2009 to examine the effects of the legal recognition of same-sex couples (through marriage or an alternative institution) on different-sex marriage, divorce, and extramarital births. Estimates from difference-in-difference models indicate that the introduction of same-sex marriage or of alternative institutions has no negative effects on family formation. These findings are robust to a multitude of specification checks, including the construction of counterfactuals using the synthetic control method. In addition, the country-by-country case studies provide evidence of homogeneity of the estimated effects.

  1. "Sex Hormones" in Secondary School Biology Textbooks

    ERIC Educational Resources Information Center

    Nehm, Ross H.; Young, Rebecca

    2008-01-01

    This study explores the extent to which the term "sex hormone" is used in science textbooks, and whether the use of the term "sex hormone" is associated with pre-empirical concepts of sex dualism, in particular the misconceptions that these so-called "sex hormones" are sex specific and restricted to sex-related physiological functioning. We found…

  2. Sex preference and fertility: what is the link?

    PubMed

    Robey, B

    1987-04-01

    It is argued that investment in programs for changing attitudes toward sex preference may not have the greatest impact on reducing fertility or increasing fertility control. Arnold's new method of analysis of determining sex preference was applied to data from a 1977 Egyptian survey of 36,000 rural households in Menoufia Governorate. Findings indicated that couples increased their use of modern contraceptives in direct proportion to an increase in the number of sons. Arnold determined that a large majority of all couples would have at least one boy early in their childbearing years. Thus sex preference would not have a large effect on fertility. Arnold's analysis among 27 countries found that without any sex preference, contraceptive usage would increase by an average of less than 3.7 percentage points. Arnold found that sex preference was strongest in Asia, particularly in South Korea and Taiwan that already have reduced fertility levels. In Africa, where fertility is high, the total elimination of sex preference would have only a 2.9 percentage point difference in contraceptive use. Sex preference had small effects on the percent of women who practice contraception, the percent who desire no more children, and the average number of additional children wanted. For example, in Bangladesh having no sex preference would show a percentage difference of 1.6 percentage points for contraceptive use, 4.7 percentage points difference for women desiring no more children, and -0.1 percentage point difference for the average number of additional children wanted. The effect of having no sex preference was strongest in India compared with Bangladesh, Indonesia, Nepal, the Philippines, Thailand, Ghana, Kenya, Costa Rica, Haiti, Paraguay, and Peru. The effect of no sex preference in India would have the respective percentage point effect of 3.7, 8.9, and -0.2. Public policy should be directed to information, education, and communication with other social goals.

  3. Sex preference and fertility: what is the link?

    PubMed

    Robey, B

    1987-04-01

    It is argued that investment in programs for changing attitudes toward sex preference may not have the greatest impact on reducing fertility or increasing fertility control. Arnold's new method of analysis of determining sex preference was applied to data from a 1977 Egyptian survey of 36,000 rural households in Menoufia Governorate. Findings indicated that couples increased their use of modern contraceptives in direct proportion to an increase in the number of sons. Arnold determined that a large majority of all couples would have at least one boy early in their childbearing years. Thus sex preference would not have a large effect on fertility. Arnold's analysis among 27 countries found that without any sex preference, contraceptive usage would increase by an average of less than 3.7 percentage points. Arnold found that sex preference was strongest in Asia, particularly in South Korea and Taiwan that already have reduced fertility levels. In Africa, where fertility is high, the total elimination of sex preference would have only a 2.9 percentage point difference in contraceptive use. Sex preference had small effects on the percent of women who practice contraception, the percent who desire no more children, and the average number of additional children wanted. For example, in Bangladesh having no sex preference would show a percentage difference of 1.6 percentage points for contraceptive use, 4.7 percentage points difference for women desiring no more children, and -0.1 percentage point difference for the average number of additional children wanted. The effect of having no sex preference was strongest in India compared with Bangladesh, Indonesia, Nepal, the Philippines, Thailand, Ghana, Kenya, Costa Rica, Haiti, Paraguay, and Peru. The effect of no sex preference in India would have the respective percentage point effect of 3.7, 8.9, and -0.2. Public policy should be directed to information, education, and communication with other social goals. PMID:12291498

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

    PubMed

    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.

  5. Sexing sperm of domestic animals.

    PubMed

    Espinosa-Cervantes, Román; Córdova-Izquierdo, Alejandro

    2013-01-01

    The ability to preselect or predetermine the sex of offspring prior to conception is a highly desired technological tool for assisted female breeding programs specifically for milk production, and in males, for meat production and increasing livestock numbers. The current technology is based on the well-known differences in X- and Y-sperm in the amount of DNA. The technology uses modified flow cytometric instrumentation for sorting X- and Y-bearing sperm. The method can be validated on the basis of live births, laboratory reanalysis of sorted sperm for DNA content, and embryo biopsy for sex determination. Currently, the sex of animals has been predetermined with 90 % accuracy by sexing spermatozoa. In the bovine breeding industry, flow cytometric sperm sexing has not fulfilled its original promise. Sexed sperm doses are too expensive for widespread application while the fertility of sexed sperm doses is lower than unsexed ones. Essentially all bovine sexed semen is frozen and then applied through artificial insemination (AI) or in vitro fertilization. There is still a need in the animal breeding industry to develop a technique for sperm sexing that provides sufficient spermatozoa for AI doses, does not compromise sperm fertility, and is widely applicable to a range of species. In this review, we will summarize the current state-of-the-art in sex preselection in domestic animals and some wildlife species using flow cytometric sperm-sorting of X from Y sperm based on DNA differences.

  6. Nonvolitional sex and sexual health.

    PubMed

    Kalmuss, Debra

    2004-06-01

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

  7. Sexing sperm of domestic animals.

    PubMed

    Espinosa-Cervantes, Román; Córdova-Izquierdo, Alejandro

    2013-01-01

    The ability to preselect or predetermine the sex of offspring prior to conception is a highly desired technological tool for assisted female breeding programs specifically for milk production, and in males, for meat production and increasing livestock numbers. The current technology is based on the well-known differences in X- and Y-sperm in the amount of DNA. The technology uses modified flow cytometric instrumentation for sorting X- and Y-bearing sperm. The method can be validated on the basis of live births, laboratory reanalysis of sorted sperm for DNA content, and embryo biopsy for sex determination. Currently, the sex of animals has been predetermined with 90 % accuracy by sexing spermatozoa. In the bovine breeding industry, flow cytometric sperm sexing has not fulfilled its original promise. Sexed sperm doses are too expensive for widespread application while the fertility of sexed sperm doses is lower than unsexed ones. Essentially all bovine sexed semen is frozen and then applied through artificial insemination (AI) or in vitro fertilization. There is still a need in the animal breeding industry to develop a technique for sperm sexing that provides sufficient spermatozoa for AI doses, does not compromise sperm fertility, and is widely applicable to a range of species. In this review, we will summarize the current state-of-the-art in sex preselection in domestic animals and some wildlife species using flow cytometric sperm-sorting of X from Y sperm based on DNA differences. PMID:22829354

  8. A rapid improved method for sexing embryo of water buffalo.

    PubMed

    Zoheir, K M A; Allam, A A

    2011-07-01

    The objective of the experiment of this paper is to develop and improve in the sexing method for preimplantation embryos of water buffalo (Bubalus bubalis) using loop-mediated isothermal amplification (LAMP) reaction. Embryo sexing has been recognized to control effectively the sex of offspring in the embryo transfer industry. A rapid and simple detection system was established by adding ethidium bromide (EB) or 5 μl of CuSO4 (3M) to the product of LAMP reaction. The result of these additions after 2 min was a color change and a precipitate. It could be employed as an alternative method in the detection of the reaction products in place of the time consuming electrophoresis or the turbidity meter. The in vitro produced buffalo embryos were divided into one to eight pieces using a microblade attached to a micromanipulator. The cell number in each piece was counted before sexing. Sexing of DNA samples extracted from one to five biopsies cells was performed by LAMP. After biopsy, the remaining part of the embryos was used to confirm the sex by polymerase chain reaction (PCR). Fifty buffalo embryos were used and the accuracy of sex prediction was 100% when the blastomeres dissociated from a morula exceeds three. In conclusion, the present procedure without turbidity meter and electrophoresis was reliable and applicable for sexing the water buffalo embryos.

  9. Comparative morphology and sex identification of the reproductive system in formalin-preserved sea turtle specimens.

    PubMed

    Ceriani, Simona A; Wyneken, Jeanette

    2008-01-01

    Sex identification in young sea turtles is challenging. Sea turtle neonates lack external dimorphic characteristics and heteromorphic sex chromosomes. We compared the morphology of the gonads and reproductive ducts of dead formalin-preserved hatchling and post-hatchling Caretta caretta, Dermochelys coriacea, and Chelonia mydas and identified sex-specific differences in these structures that are useful in assigning sex. We tested 11 gross gonadal and reproductive duct characteristics in 57 neonate sea turtles and verified the sex by histological examination. A suite of four characters was found to reliably indicate sex in the three species considered: paramesonephric duct size, mobility of the duct, presence of a complete lumen and gonad mobility. Additionally, gonad shape and edge form were dependable sex-specific characters in cheloniids but not in D. coriacea. Together, these morphological characteristics provide new and reliable methods to quickly distinguish sex in preserved neonate sea turtles without using more extensive histological methods.

  10. Management of disorders of sex development.

    PubMed

    Hiort, Olaf; Birnbaum, Wiebke; Marshall, Louise; Wünsch, Lutz; Werner, Ralf; Schröder, Tatjana; Döhnert, Ulla; Holterhus, Paul-Martin

    2014-09-01

    The medical term disorders of sex development (DSDs) is used to describe individuals with an atypical composition of chromosomal, gonadal and phenotypic sex, which leads to differences in the development of the urogenital tract and reproductive system. A variety of genetic factors have been identified that affect sex development during gonadal differentiation or in specific disorders associated with altered androgen biosynthesis or action. The diagnosis of DSDs in individuals and the subsequent management of patients and their families requires a targeted and structured approach, involving a multidisciplinary team with effective communication between the disciplines. This approach includes distinct clinical, imaging, laboratory and genetic evaluations of patients with DSDs. Although treatment of patients with DSDs can include endocrine and surgical options, many patients have concerns that arise from past incorrect treatments that were founded on the traditional binary concept of the sexes. To dispel these concerns, it is necessary to create centres of expertise for DSDs that include physicians, surgeons, psychologists and specialists in diagnostic procedures to manage patients and their families. Additionally, the inclusion of trained peer support in the multidisciplinary DSD team seems to be integral to the supportive management of patients with DSDs. Most importantly, dealing with DSDs requires acceptance of the fact that deviation from the traditional definitions of gender is not necessarily pathologic. PMID:25022812

  11. Sexing California Clapper Rails using morphological measurements

    USGS Publications Warehouse

    Overton, Cory T.; Casazza, Michael L.; Takekawa, John Y.; Rohmer, Tobias M.

    2009-01-01

    California Clapper Rails (Rallus longirostris obsoletus) have monomorphic plumage, a trait that makes identification of sex difficult without extensive behavioral observation or genetic testing. Using 31 Clapper Rails (22 females, 9 males), caught in south San Francisco Bay, CA, and using easily measurable morphological characteristics, we developed a discriminant function to distinguish sex. We then validated this function on 33 additional rails. Seven morphological measurements were considered, resulting in three which were selected in the discriminate function: culmen length, tarsometatarsus length, and flat wing length. We had no classification errors for the development or testing datasets either with resubstitution or cross-validation procedures. Male California Clapper Rails were 6-22% larger than females for individual morphological traits, and the largest difference was in body mass.  Variables in our discriminant function closely match variables developed for sexing Clapper Rails of Gulf Coast populations. However, a universal discriminant function to sex all Clapper Rail subspecies is not likely because of large and inconsistent differences in morphological traits among subspecies. 

  12. Management of disorders of sex development.

    PubMed

    Hiort, Olaf; Birnbaum, Wiebke; Marshall, Louise; Wünsch, Lutz; Werner, Ralf; Schröder, Tatjana; Döhnert, Ulla; Holterhus, Paul-Martin

    2014-09-01

    The medical term disorders of sex development (DSDs) is used to describe individuals with an atypical composition of chromosomal, gonadal and phenotypic sex, which leads to differences in the development of the urogenital tract and reproductive system. A variety of genetic factors have been identified that affect sex development during gonadal differentiation or in specific disorders associated with altered androgen biosynthesis or action. The diagnosis of DSDs in individuals and the subsequent management of patients and their families requires a targeted and structured approach, involving a multidisciplinary team with effective communication between the disciplines. This approach includes distinct clinical, imaging, laboratory and genetic evaluations of patients with DSDs. Although treatment of patients with DSDs can include endocrine and surgical options, many patients have concerns that arise from past incorrect treatments that were founded on the traditional binary concept of the sexes. To dispel these concerns, it is necessary to create centres of expertise for DSDs that include physicians, surgeons, psychologists and specialists in diagnostic procedures to manage patients and their families. Additionally, the inclusion of trained peer support in the multidisciplinary DSD team seems to be integral to the supportive management of patients with DSDs. Most importantly, dealing with DSDs requires acceptance of the fact that deviation from the traditional definitions of gender is not necessarily pathologic.

  13. Animal models of absence epilepsies: What do they model and do sex and sex hormones matter?

    PubMed Central

    van Luijtelaar, Gilles; Onat, Filiz Yilmaz; Gallagher, Martin J.

    2014-01-01

    While epidemiological data suggest a female prevalence in human childhood- and adolescence-onset typical absence epilepsy syndromes, the sex difference is less clear in adult-onset syndromes. In addition, although there are more females than males diagnosed with typical absence epilepsy syndromes, there is a paucity of studies on sex differences in seizure frequency and semiology in patients diagnosed with any absence epilepsy syndrome. Moreover, it is unknown if there are sex differences in the prevalence or expression of atypical absence epilepsy syndromes. Surprisingly, most studies of animal models of absence epilepsy either did not investigate sex differences, or failed to find sex-dependent effects. However, various rodent models for atypical syndromes such as the AY9944 model (prepubertal females show a higher incidence than prepubertal males), BN model also with a higher prevalence in males and the Gabra1 deletion mouse in the C57BL/6J strain offer unique possibilities for the investigation of the mechanisms involved in sex differences. Although the mechanistic bases for the sex differences in humans or these three models are not yet known, studies of the effects of sex hormones on seizures have offered some possibilities. The sex hormones progesterone, estradiol and testosterone exert diametrically opposite effects in genetic absence epilepsy and pharmacologically-evoked convulsive types of epilepsy models. In addition, acute pharmacological effects of progesterone on absence seizures during proestrus are opposite to those seen during pregnancy. 17β-Estradiol has anti-absence seizure effects, but it is only active in atypical absence models. It is speculated that the pro-absence action of progesterone, and perhaps also the delayed pro-absence action of testosterone, are mediated through the neurosteroid allopregnanolone and its structural and functional homolog, androstanediol. These two steroids increase extrasynaptic thalamic tonic GABAergic inhibition

  14. Animal models of absence epilepsies: what do they model and do sex and sex hormones matter?

    PubMed

    van Luijtelaar, Gilles; Onat, Filiz Yilmaz; Gallagher, Martin J

    2014-12-01

    While epidemiological data suggest a female prevalence in human childhood- and adolescence-onset typical absence epilepsy syndromes, the sex difference is less clear in adult-onset syndromes. In addition, although there are more females than males diagnosed with typical absence epilepsy syndromes, there is a paucity of studies on sex differences in seizure frequency and semiology in patients diagnosed with any absence epilepsy syndrome. Moreover, it is unknown if there are sex differences in the prevalence or expression of atypical absence epilepsy syndromes. Surprisingly, most studies of animal models of absence epilepsy either did not investigate sex differences, or failed to find sex-dependent effects. However, various rodent models for atypical syndromes such as the AY9944 model (prepubertal females show a higher incidence than prepubertal males), BN model (also with a higher prevalence in males) and the Gabra1 deletion mouse in the C57BL/6J strain offer unique possibilities for the investigation of the mechanisms involved in sex differences. Although the mechanistic bases for the sex differences in humans or these three models are not yet known, studies of the effects of sex hormones on seizures have offered some possibilities. The sex hormones progesterone, estradiol and testosterone exert diametrically opposite effects in genetic absence epilepsy and pharmacologically-evoked convulsive types of epilepsy models. In addition, acute pharmacological effects of progesterone on absence seizures during proestrus are opposite to those seen during pregnancy. 17β-Estradiol has anti-absence seizure effects, but it is only active in atypical absence models. It is speculated that the pro-absence action of progesterone, and perhaps also the delayed pro-absence action of testosterone, are mediated through the neurosteroid allopregnanolone and its structural and functional homolog, androstanediol. These two steroids increase extrasynaptic thalamic tonic GABAergic

  15. The influence of observers' sex on attention-demanding performance depends on performers' sex.

    PubMed

    Wang, Lijun; Tan, Jinfeng; Chen, Jiangtao; Chen, Antao

    2015-01-01

    Post-error slowing (PES) indicates the slower responses after errors than after correct responses. Prior studies mainly focus on how the observation errors influence one own's performance, there is no study investigating how other's monitoring influence one own's performance. Additionally, the issue that whether social context influences the PES effect differently for females and males is still unclear. To address aforementioned issues, we required the participants to interact with a same-sex or opposite-sex partner to complete a color flanker task together (they sat next to each other, Experiment 1). One was the performer (perform the flanker task), and the other was the observer (monitor the error responses of performer). They alternated their roles in two successive blocks. To further verify the role of the interaction context, a control experiment was conducted in the individual context (Experiment 2). The results revealed that (1) larger PES effect was observed in females than in males in the interaction context; (2) the sex difference of PES effect mainly benefited from the opposite-sex interaction; (3) larger PES effect was observed in the interaction context than in the individual context; (4) females' performance was influenced after an interaction with a same-sex or opposite-sex partner, whereas males' performance was merely influenced after an interaction with an opposite-sex partner. Taken together, these findings may suggest that (1) interaction context modulates the PES effect differently for females and males; (2) females are more susceptible to social information and hence more effective to adjust the post-error behaviors. PMID:26379574

  16. Sex differences in sleep: impact of biological sex and sex steroids.

    PubMed

    Mong, Jessica A; Cusmano, Danielle M

    2016-02-19

    Men and women sleep differently. While much is known about the mechanisms that drive sleep, the reason for these sex differences in sleep behaviour is unknown and understudied. Historically, women and female animals are underrepresented in studies of sleep and its disorders. Nevertheless, there is a growing recognition of sex disparities in sleep and rhythm disorders. Women typically report poorer quality and more disrupted sleep across various stages of life. Findings from clinical and basic research studies strongly implicate a role for sex steroids in sleep modulation. Understanding how neuroendocrine mediators and sex differences influence sleep is central to advancing our understanding of sleep-related disorders. The investigation into sex differences and sex steroid modulation of sleep is in its infancy. Identifying the mechanisms underlying sex and gender differences in sleep will provide valuable insights leading to tailored therapeutics that benefit each sex. The goal of this review is to discuss our current understanding of how biological sex and sex steroids influence sleep behaviour from both the clinical and pre-clinical perspective. PMID:26833831

  17. Practicing safer sex.

    PubMed

    DeBrow, M E

    1989-01-01

    The risk of becoming infected with the HIV virus makes it imperative to practice safe sex. The HIV virus is found in several body fluids, but transmission occurs only when sexual contact with blood, semen or vaginal fluids is made. Actions considered safe include, hugging, holding, cuddling, kissing, and masturbation without body fluid contact. Actions considered possibly safe include French kissing, intercourse with condom, and oral sex before body fluid transmission. The actions considered unsafe include intercourse without a condom or oral contact with semen, sperm, menstrual fluid, urine, or vaginal fluids. The improper use of condoms causes 98% of the failures in their use, since they seldom have defects. They need to be stored in a cool dry place and handled carefully before, during and after use. Air should be removed before putting on a condom to prevent breakage. Water-soluble lubricants should be used since oil-based lubricants cause damage to condoms. After ejaculation the condom should be held around the base to avoid spilling fluids. Condoms should only be used once and thrown away immediately after use. PMID:2703251

  18. Disorders of Sex Development

    PubMed Central

    Kim, Jongwon

    2012-01-01

    The birth of a new baby is one of the most dramatic events in a family, and the first question is usually "is it a boy or a girl?" The newborn infant with ambiguous external genitalia often comes as a surprise for the doctors as well as the parents and is sometimes described as an endocrine emergency situation presenting a problem of sex assignment. The nomenclature such as 'intersex', 'hermaphrodite', and 'pseudohermaphrodite' is out of date as well as confusing, and many urologists are concerned that these confusing terms could be perceived to be pejorative by some affected families. In response to concerns regarding outdated and controversial terms, the Chicago Consensus held in 2005 recommended new terminology based on the umbrella term disorders of sex differentiation (DSDs). The term DSD has a comprehensive definition including any problem noted at birth in which the genitalia are atypical in relation to the chromosomes or gonads. The karyotype is used as a prefix defining the classification of DSD. DSDs are rare and complex. The optimal management of patients with DSD must be individualized and multidisciplinary, considering all aspects, including psychological care and full disclosure of alternatives relating to surgery type and timing. Although further studies are necessary to confirm guidelines and recommendations fitting for the individual patients with DSD, this article is an attempt to provide a balanced perspective for new taxonomy, clinical evaluation, and medical, surgical, and psychological management of DSD. PMID:22323966

  19. Disorders of sex development.

    PubMed

    Kim, Kun Suk; Kim, Jongwon

    2012-01-01

    The birth of a new baby is one of the most dramatic events in a family, and the first question is usually "is it a boy or a girl?" The newborn infant with ambiguous external genitalia often comes as a surprise for the doctors as well as the parents and is sometimes described as an endocrine emergency situation presenting a problem of sex assignment. The nomenclature such as 'intersex', 'hermaphrodite', and 'pseudohermaphrodite' is out of date as well as confusing, and many urologists are concerned that these confusing terms could be perceived to be pejorative by some affected families. In response to concerns regarding outdated and controversial terms, the Chicago Consensus held in 2005 recommended new terminology based on the umbrella term disorders of sex differentiation (DSDs). The term DSD has a comprehensive definition including any problem noted at birth in which the genitalia are atypical in relation to the chromosomes or gonads. The karyotype is used as a prefix defining the classification of DSD. DSDs are rare and complex. The optimal management of patients with DSD must be individualized and multidisciplinary, considering all aspects, including psychological care and full disclosure of alternatives relating to surgery type and timing. Although further studies are necessary to confirm guidelines and recommendations fitting for the individual patients with DSD, this article is an attempt to provide a balanced perspective for new taxonomy, clinical evaluation, and medical, surgical, and psychological management of DSD. PMID:22323966

  20. Sex as a response to oxidative stress: stress genes co-opted for sex.

    PubMed

    Nedelcu, Aurora M

    2005-09-22

    Despite a great deal of interest, the evolutionary origins and roles of sex remain unclear. Recently, we showed that in the multicellular green alga, Volvox carteri, sex is a response to increased levels of reactive oxygen species (ROS), which could be indicative of the ancestral role of sex as an adaptive response to stress-induced ROS. To provide additional support for the suggestion that sex evolved as a response to oxidative stress, this study addresses the hypothesis that genes involved in sexual induction are evolutionarily related to genes associated with various stress responses. In particular, this study investigates the evolutionary history of genes specific to the sexual induction process in V. carteri--including those encoding the sexual inducer (SI) and several SI-induced extracellular matrix (ECM) proteins. Surprisingly, (i) a highly diversified multigene family with similarity to the V. carteri SI and SI-induced pherophorin family is present in its unicellular relative, Chlamydomonas reinhardtii (which lacks both a SI and an ECM) and (ii) at least half of the 12 identified gene members are induced (as inferred from reported expressed sequence tags) under various stress conditions. These findings suggest an evolutionary connection between sex and stress at the gene level, via duplication and/or co-option.

  1. Commentary: sex offenders and insanity.

    PubMed

    O'Shaughnessy, Roy J

    2007-01-01

    Sex offenders with a psychotic illness present challenges in the determination of criminal responsibility, risk assessment, and psychiatric treatment. Novak et al. present data that raise concerns regarding how forensic psychiatrists could conclude sex offenders were not responsible for their offenses in the absence of clear evidence of psychotic symptoms at the time of assessment and/or offense. They also highlight issues of risk assessment and management of psychotic sex offenders that have not been adequately studied. We require further research of psychotic sex offenders to be able to offer scientifically supported opinions on risk assessment to courts and decision-makers.

  2. Erroneous theories of sex determination.

    PubMed Central

    Mittwoch, U

    1985-01-01

    Throughout the major part of history, theories of sex determination had to be formulated in the absence of knowledge of ova and spermatozoa. The most persistent theory postulated that males are associated with the right parental side and females with the left side. At the end of the 19th century, sex was thought to be determined by nutrition. Recent findings regarding bilateral asymmetry in human hermaphrodites and of temperature dependent sex determination in reptiles may restore a small degree of credibility to certain theories predating the discovery of sex chromosomes. Images PMID:3892005

  3. Mixed-Sex or Single-Sex Education: How Would Young People Like Their Sex Education and Why?

    ERIC Educational Resources Information Center

    Strange, Vicki; Forrest, Simon; Oakley, Ann

    2003-01-01

    Examined adolescents views about sex education, specifically their views about interaction in single- and mixed-sex groups. Surveys of English secondary school students indicated that most girls, and one-third of boys, want some or all of their sex education to be delivered in single-sex groups. Girls' experiences of sex education with boys…

  4. Heritability of life span is largely sex limited in Drosophila.

    PubMed

    Lehtovaara, Anne; Schielzeth, Holger; Flis, Ilona; Friberg, Urban

    2013-11-01

    Males and females differ with respect to life span and rate of aging in most animal species. Such sexual dimorphism can be associated with a complex genetic architecture, where only part of the genetic variation is shared between the sexes. However, the extent to which this is true for life span and aging is not known, because studies of life span have given contradictory results and aging has not been studied from this perspective. Here we investigate the additive genetic architecture of life span and aging in Drosophila melanogaster. We find substantial amounts of additive genetic variation for both traits, with more than three-quarters of this variation available for sex-specific evolutionary change. This result shows that the sexes have a profoundly different additive genetic basis for these traits, which has several implications. First, it translates into an, on average, three-times-higher heritability of life span within, compared to between, the sexes. Second, it implies that the sexes are relatively free to evolve with respect to these traits. And third, as life span and aging are traits that integrate over all genetic factors that contribute to mortal disease, it also implies that the genetics of heritable disease differs vastly between the sexes.

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

    ERIC Educational Resources Information Center

    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…

  6. Sex Knowledge, Sex Guilt and Sexual Behavior among University Students.

    ERIC Educational Resources Information Center

    Brown, Idalyn S.; Pollack, Robert H.

    Previous research has suggested a high level of sexual activity among students, often involving unprotected intercourse. To better understand what factors contribute to consistent use of effective contraception, the relationship between sexual knowledge and sexual behavior and the relationship of sex guilt to sex knowledge were investigated in a…

  7. Teacher Expressiveness: Effects of Teacher Sex and Student Sex.

    ERIC Educational Resources Information Center

    Basow, Susan A.

    Student ratings of college professors play an important role in many employment decisions. One factor strongly associated with student ratings is teacher expressiveness. A study was conducted to explore the effects of teacher expressiveness, teacher sex, and student sex on student ratings of their instructor, student perceptions of their…

  8. Sex differences in dental caries experience: clinical evidence, complex etiology.

    PubMed

    Lukacs, John R

    2011-10-01

    A sex difference in oral health has been widely documented through time and across cultures. Women's oral health declines more rapidly than men's with the onset of agriculture and the associated rise in fertility. The magnitude of this disparity in oral health by sex increases during ontogeny: from childhood, to adolescence, and through the reproductive years. Representative studies of sex differences in caries, tooth loss, and periodontal disease are critically reviewed. Surveys conducted in Hungary, India, and in an isolated traditional Brazilian sample provide additional support for a significant sex bias in dental caries, especially in mature adults. Compounding hormonal and reproductive factors, the sex difference in oral health in India appears to involve social and religious causes such as son preference, ritual fasting, and dietary restrictions during pregnancy. Like the sex difference in caries, tooth loss in women is greater than in men and has been linked to caries and parity. Results of genome wide association studies have found caries susceptible and caries protective loci that influence variation in taste, saliva, and enamel proteins, affecting the oral environment and the micro-structure of enamel. Genetic variation, some of which is X-linked, may partly explain how sex differences in oral health originate. A primary, but neglected, factor in explaining the sex differential in oral health is the complex and synergistic changes associated with female sex hormones, pregnancy, and women's reproductive life history. Caries etiology is complex and impacts understanding of the sex difference in oral health. Both biological (genetics, hormones, and reproductive history) and anthropological (behavioral) factors such culture-based division of labor and gender-based dietary preferences play a role.

  9. Fungal Sex and Pathogenesis

    PubMed Central

    Butler, Geraldine

    2010-01-01

    Summary: Human fungal pathogens are associated with diseases ranging from dandruff and skin colonization to invasive bloodstream infections. The major human pathogens belong to the Candida, Aspergillus, and Cryptococcus clades, and infections have high and increasing morbidity and mortality. Many human fungal pathogens were originally assumed to be asexual. However, recent advances in genome sequencing, which revealed that many species have retained the genes required for the sexual machinery, have dramatically influenced our understanding of the biology of these organisms. Predictions of a rare or cryptic sexual cycle have been supported experimentally for some species. Here, I examine the evidence that human pathogens reproduce sexually. The evolution of the mating-type locus in ascomycetes (including Candida and Aspergillus species) and basidiomycetes (Malassezia and Cryptococcus) is discussed. I provide an overview of how sex is suppressed in different species and discuss the potential associations with pathogenesis. PMID:20065328

  10. Fungal sex and pathogenesis.

    PubMed

    Butler, Geraldine

    2010-01-01

    Human fungal pathogens are associated with diseases ranging from dandruff and skin colonization to invasive bloodstream infections. The major human pathogens belong to the Candida, Aspergillus, and Cryptococcus clades, and infections have high and increasing morbidity and mortality. Many human fungal pathogens were originally assumed to be asexual. However, recent advances in genome sequencing, which revealed that many species have retained the genes required for the sexual machinery, have dramatically influenced our understanding of the biology of these organisms. Predictions of a rare or cryptic sexual cycle have been supported experimentally for some species. Here, I examine the evidence that human pathogens reproduce sexually. The evolution of the mating-type locus in ascomycetes (including Candida and Aspergillus species) and basidiomycetes (Malassezia and Cryptococcus) is discussed. I provide an overview of how sex is suppressed in different species and discuss the potential associations with pathogenesis. PMID:20065328

  11. Mallard age and sex determination from wings

    USGS Publications Warehouse

    Carney, S.M.; Geis, A.D.

    1960-01-01

    This paper describes characters on the wing plumage of the mallard that indicate age and sex. A key outlines a logical order in which to check age and sex characters on wings. This method was tested and found to be more than 95 percent reliable, although it was found that considerable practice and training with known-age specimens was required to achieve this level of accuracy....The implications of this technique and the sampling procedure it permits are discussed. Wing collections could provide information on production, and, if coupled with a banding program could permit seasonal population estimates to be calculated. In addition, representative samples of wings would provide data to check the reliability of several other waterfowl surveys.

  12. Sex Differences in the Heritability of Resilience

    PubMed Central

    Boardman, Jason D.; Blalock, Casey L.; Button, Tanya M. M.

    2009-01-01

    We examine the heritability of psychological resilience among US adults aged 25 to 74 years. Using monozygotic and same sex dizygotic twin pairs from the National Survey of Mid-Life Development in the United States (MIDUS) we show that positive affect is equally heritable among men (h2 = .60) and women (h2 = .59). We then estimate the heritability of positive affect after controlling for an exhaustive list of social and interpersonal stressors, and we operationalize the residual for positive affect as resilience. According to this specification, the heritability of resilience is higher among men (h2 = .52) compared to women (h2 = .38). We show that self-acceptance is one of the most important aspects of psychological functioning that accounts for the heritability of resilience among both men and women. However, compared to women, men appear to derive additional benefits from environmental mastery that may enable otherwise sex-neutral resilient tendencies to manifest. PMID:18251671

  13. Colombia's "National Project for Sex Education".

    PubMed

    Martinez Mendez, Z

    1996-01-01

    Colombia's National Project for Sex Education, established in 1993, seeks to change negative views of sexuality, further social justice through a redefinition of traditional gender roles, promote reproductive health and sexual responsibility, and encourage respect and self-determination within families. Given the racial and cultural diversity within Colombian society, as well as a trend toward school decentralization and autonomy, there is no single curriculum. To date, more than 2000 teachers have attended 180 workshops on human sexuality. To ensure a future supply of trained teachers, universities are being asked to implement sex education studies. In addition, 36 regional teams have been formed and 145 people have been trained in program development. 12 sexuality education booklets have been prepared, as well as poster displays, media advertisements, and videotapes. Program evaluation will be an important component of this strategy.

  14. The Consequences of Sex Selection

    ERIC Educational Resources Information Center

    Rothman, Barbara Katz

    2006-01-01

    A group of researchers at Baylor College of Medicine in Houston are set to do a long-term study of families that would permit to select the sex of their babies through genetic testing before implanting the embryo in the mother. Technologies such as in vitro fertilization involved in selecting a baby's sex has societal and psychological…

  15. Making scents of sex underwater.

    PubMed

    Bentley, M G; Watson, G J

    2000-11-01

    Sex and scents have long been associated. Musk, for example, is a sexual scent that has been used for many years in the perfume industry. In humans, the debate on the existence of sex pheromones continues, whereas in insects their role is well known. Through recent research, we are discovering that such chemicals are equally important in conveying sexual signals between aquatic animals.

  16. Sex Differences in Fetal Habituation

    ERIC Educational Resources Information Center

    Hepper, Peter G.; Dornan, James C.; Lynch, Catherine

    2012-01-01

    There is some evidence for sex differences in habituation in the human fetus, but it is unknown whether this is due to differences in central processing (habituation) or in more peripheral processes, sensory or motor, involved in the response. This study examined whether the sex of the fetus influenced auditory habituation at 33 weeks of…

  17. Sex Differences in the Brain.

    ERIC Educational Resources Information Center

    Kimura, Doreen

    1992-01-01

    Explores the neural and hormonal basis of human intellectual function that gives rise to sex differences in the brain. Discusses behavioral, neurological, endocrinological studies, and studies of the effects of hormones on brain functioning that show a relationship between cognitive variations and sex. (MCO)

  18. Brain Dysfunction in Sex Offenders.

    ERIC Educational Resources Information Center

    Galski, Thomas; And Others

    1990-01-01

    Attempted to establish the connection between disordered sexuality and brain impairment by using newly developed techniques of neuropsychological investigation with sex offenders (n=35). Results indicated a major portion of the sex offenders showed impaired brain functioning on Luria-Nebraska Neuropsychological Battery. (Author/ABL)

  19. Sex Differences in Work Values.

    ERIC Educational Resources Information Center

    Beutell, Nicholas J.; Brenner, O. C.

    1986-01-01

    Investigated sex differences in work values. Significant sex differences were found on 18 of 25 values with women rating 12 of these values higher than men. However, despite item differences, there was a clear trend toward similarity in the importance of work outcomes among women and men. (Author/BL)

  20. Teaching Sex Education in Thailand

    ERIC Educational Resources Information Center

    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:…

  1. Additional renal arteries: incidence and morphometry.

    PubMed

    Satyapal, K S; Haffejee, A A; Singh, B; Ramsaroop, L; Robbs, J V; Kalideen, J M

    2001-01-01

    Advances in surgical and uro-radiological techniques dictate a reappraisal and definition of renal arterial variations. This retrospective study aimed at establishing the incidence of additional renal arteries. Two subsets were analysed viz.: a) Clinical series--130 renal angiograms performed on renal transplant donors, 32 cadaver kidneys used in renal transplantation b) Cadaveric series--74 en-bloc morphologically normal kidney pairs. The sex and race distribution was: males 140, females 96; African 84, Indian 91, White 43 and "Coloured" 18, respectively. Incidence of first and second additional arteries were respectively, 23.2% (R: 18.6%; L: 27.6%) and 4.5% (R: 4.7%; L: 4.4%). Additional arteries occurred more frequently on the left (L: 32.0%; R: 23.3%). The incidence bilaterally was 10.2% (first additional arteries, only). The sex and race incidence (first and second additional) was: males, 28.0%, 5.1%; females, 16.4%, 3.8% and African 31.1%, 5.4%; Indian 13.5%, 4.5%; White 30.9%, 4.4% and "Coloured" 18.5%, 0%; respectively. Significant differences in the incidence of first additional arteries were noted between sex and race. The morphometry of additional renal arteries were lengths (cm) of first and second additional renal arteries: 4.5 and 3.8 (right), 4.9 and 3.7 (left); diameters: 0.4 and 0.3 (right), 0.3 and 0.3 (left). Detailed morphometry of sex and race were also recorded. No statistically significant differences were noted. Our results of the incidence of additional renal arteries of 27.7% compared favourably to that reported in the literature (weighted mean 28.1%). The study is unique in recording detailed morphometry of these vessels. Careful techniques in the identification of this anatomical variation is important since it impacts on renal transplantation surgery, vascular operations for renal artery stenosis, reno-vascular hypertension, Takayasu's disease, renal trauma and uro-radiological procedures.

  2. In Search of Emerging Same-Sex Sexuality: Romantic Attractions at Age 13 Years.

    PubMed

    Li, Gu; Hines, Melissa

    2016-10-01

    Sex-typed behavior in childhood is significantly related to sexual orientation in adulthood. In addition, same-sex attractions in early adolescence are more non-exclusive than in adulthood and can differ from later same-sex orientations. However, little research has focused on romantic attractions as they emerge during early adolescence. Drawing a sample from the Avon Longitudinal Study of Parents and Children (197 girls, 204 boys), the current study examined whether same-sex romantic attractions at age 13 years were exclusive, and whether they were predicted by sex-typed behavior at age 3.5 years. No young adolescents in this sample reported exclusive same-sex attractions, and increased same-sex attractions were not significantly related to reduced other-sex sexualities. Childhood sex-typed behavior did not significantly predict early same-sex attractions, suggesting that early same-sex attractions differ from later same-sex orientations. The current study highlights the importance of studying the development of sexuality beginning prior to adulthood.

  3. The Female Sex Work Industry in a District of India in the Context of HIV Prevention.

    PubMed

    Buzdugan, Raluca; Halli, Shiva S; Hiremath, Jyoti M; Jayanna, Krishnamurthy; Raghavendra, T; Moses, Stephen; Blanchard, James; Scambler, Graham; Cowan, Frances

    2012-01-01

    HIV prevalence in India remains high among female sex workers. This paper presents the main findings of a qualitative study of the modes of operation of female sex work in Belgaum district, Karnataka, India, incorporating fifty interviews with sex workers. Thirteen sex work settings (distinguished by sex workers' main places of solicitation and sex) are identified. In addition to previously documented brothel, lodge, street, dhaba (highway restaurant), and highway-based sex workers, under-researched or newly emerging sex worker categories are identified, including phone-based sex workers, parlour girls, and agricultural workers. Women working in brothels, lodges, dhabas, and on highways describe factors that put them at high HIV risk. Of these, dhaba and highway-based sex workers are poorly covered by existing interventions. The paper examines the HIV-related vulnerability factors specific to each sex work setting. The modes of operation and HIV-vulnerabilities of sex work settings identified in this paper have important implications for the local programme.

  4. Evolutionary transitions between sex-determining mechanisms: a review of theory.

    PubMed

    van Doorn, G S

    2014-01-01

    The extraordinary diversity of sex-determining mechanisms found in nature is thought to have arisen by the addition, modification or replacement of regulators at the upstream end of the sex-determining pathway. The spread of a novel regulator of sex determination can manifest itself by an evolutionary transition between environmental and genetic sex determination, for example, or between male and female heterogamety. Both kinds of transition have occurred frequently in the course of evolution. In this paper, various evolutionary forces acting on sex-determining mutations that can bias transitions in one direction or the other are reviewed. Furthermore, the adaptive significance of the main modes of sex determination are discussed, and the common principle underlying ultimate explanations for environmental sex determination, genetic sex determination and maternal control over sex determination in the offspring are highlighted. Most of the current theory concentrates on the population-genetic aspects of sex determination transitions, using models that do not reflect the developmental mechanisms involved in sex determination. However, the increasing availability of molecular data creates opportunities for the future development of mechanistic models that will further clarify how selection and developmental architecture interact to direct the evolution of sex determination genes. PMID:24335102

  5. The joy of sex pheromones

    PubMed Central

    Gomez-Diaz, Carolina; Benton, Richard

    2013-01-01

    Sex pheromones provide an important means of communication to unite individuals for successful reproduction. Although sex pheromones are highly diverse across animals, these signals fulfil common fundamental roles in enabling identification of a mating partner of the opposite sex, the appropriate species and of optimal fecundity. In this review, we synthesize both classic and recent investigations on sex pheromones in a range of species, spanning nematode worms, insects and mammals. These studies reveal comparable strategies in how these chemical signals are produced, detected and processed in the brain to regulate sexual behaviours. Elucidation of sex pheromone communication mechanisms both defines outstanding models to understand the molecular and neuronal basis of chemosensory behaviours, and reveals how similar evolutionary selection pressures yield convergent solutions in distinct animal nervous systems. EMBO reports advance online publication 13 September 2013; doi:10.1038/embor.2013.140 PMID:24030282

  6. Sex Hormones and Immune Dimorphism

    PubMed Central

    Bhatia, Aruna; Sekhon, Harmandeep Kaur; Kaur, Gurpreet

    2014-01-01

    The functioning of the immune system of the body is regulated by many factors. The abnormal regulation of the immune system may result in some pathological conditions. Sex hormones of reproductive system are one of the major factors that regulate immune system due to the presence of hormone receptors on immune cells. The interaction of sex hormones and immune cells through the receptors on these cells effect the release of cytokines which determines the proliferation, differentiation, and maturation of different types of immunocytes and as a result the outcome of inflammatory or autoimmune diseases. The different regulations of sex hormones in both sexes result in immune dimorphism. In this review article the mechanism of regulation of immune system in different sexes and its impact are discussed. PMID:25478584

  7. Sex differences in primary hypertension

    PubMed Central

    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

  8. Deleterious mutations and selection for sex in finite diploid populations.

    PubMed

    Roze, Denis; Michod, Richard E

    2010-04-01

    In diploid populations, indirect benefits of sex may stem from segregation and recombination. Although it has been recognized that finite population size is an important component of selection for recombination, its effects on selection for segregation have been somewhat less studied. In this article, we develop analytical two- and three-locus models to study the effect of recurrent deleterious mutations on a modifier gene increasing sex, in a finite diploid population. The model also incorporates effects of mitotic recombination, causing loss of heterozygosity (LOH). Predictions are tested using multilocus simulations representing deleterious mutations occurring at a large number of loci. The model and simulations show that excess of heterozygosity generated by finite population size is an important component of selection for sex, favoring segregation when deleterious alleles are nearly additive to dominant. Furthermore, sex tends to break correlations in homozygosity among selected loci, which disfavors sex when deleterious alleles are either recessive or dominant. As a result, we find that it is difficult to maintain costly sex when deleterious alleles are recessive. LOH tends to favor sex when deleterious mutations are recessive, but the effect is relatively weak for rates of LOH corresponding to current estimates (of the order 10(-4)-10(-5)).

  9. Identification of the sex genes in an early diverged fungus.

    PubMed

    Idnurm, Alexander; Walton, Felicia J; Floyd, Anna; Heitman, Joseph

    2008-01-10

    Sex determination in fungi is controlled by a small, specialized region of the genome in contrast to the large sex-specific chromosomes of animals and some plants. Different gene combinations reside at these mating-type (MAT) loci and confer sexual identity; invariably they encode homeodomain, alpha-box, or high mobility group (HMG)-domain transcription factors. So far, MAT loci have been characterized from a single monophyletic clade of fungi, the Dikarya (the ascomycetes and basidiomycetes), and the ancestral state and evolutionary history of these loci have remained a mystery. Mating in the basal members of the kingdom has been less well studied, and even their precise taxonomic inter-relationships are still obscure. Here we apply bioinformatic and genetic mapping to identify the sex-determining (sex) region in Phycomyces blakesleeanus (Zygomycota), which represents an early branch within the fungi. Each sex allele contains a single gene that encodes an HMG-domain protein, implicating the HMG-domain proteins as an earlier form of fungal MAT loci. Additionally, one allele also contains a copy of a unique, chromosome-specific repetitive element, suggesting a generalized mechanism for the earliest steps in the evolution of sex determination and sex chromosome structure in eukaryotes.

  10. Sex-specific determinants of fitness in a social mammal.

    PubMed

    Lardy, Sophie; Allainé, Dominique; Bonenfant, Christophe; Cohas, Aurélie

    2015-11-01

    Sociality should evolve when the fitness benefits of group living outweigh the costs. Theoretical models predict an optimal group size maximizing individual fitness. However, beyond the number of individuals present in a group, the characteristics of these individuals, like their sex, are likely to affect the fitness payoffs of group living. Using 20 years of individually based data on a social mammal, the Alpine marmot (Marmota marmota), we tested for the occurrence of an optimal group size and composition, and for sex-specific effects of group characteristics on fitness. Based on lifetime data of 52 males and 39 females, our findings support the existence of an optimal group size maximizing male fitness and an optimal group composition maximizing fitness of males and females. Additionally, although group characteristics (i.e., size, composition and instability) affecting male and female fitness differed, fitness depended strongly on the number of same-sex subordinates within the social group in the two sexes. By comparing multiple measures of social group characteristics and of fitness in both sexes, we highlighted the sex-specific determinants of fitness in the two sexes and revealed the crucial role of intrasexual competition in shaping social group composition.

  11. Sex-specific determinants of fitness in a social mammal.

    PubMed

    Lardy, Sophie; Allainé, Dominique; Bonenfant, Christophe; Cohas, Aurélie

    2015-11-01

    Sociality should evolve when the fitness benefits of group living outweigh the costs. Theoretical models predict an optimal group size maximizing individual fitness. However, beyond the number of individuals present in a group, the characteristics of these individuals, like their sex, are likely to affect the fitness payoffs of group living. Using 20 years of individually based data on a social mammal, the Alpine marmot (Marmota marmota), we tested for the occurrence of an optimal group size and composition, and for sex-specific effects of group characteristics on fitness. Based on lifetime data of 52 males and 39 females, our findings support the existence of an optimal group size maximizing male fitness and an optimal group composition maximizing fitness of males and females. Additionally, although group characteristics (i.e., size, composition and instability) affecting male and female fitness differed, fitness depended strongly on the number of same-sex subordinates within the social group in the two sexes. By comparing multiple measures of social group characteristics and of fitness in both sexes, we highlighted the sex-specific determinants of fitness in the two sexes and revealed the crucial role of intrasexual competition in shaping social group composition. PMID:27070014

  12. A qualitative exploration of female sex work in Tijuana, Mexico.

    PubMed

    Bucardo, Jesus; Semple, Shirley J; Fraga-Vallejo, Miguel; Davila, Wendy; Patterson, Thomas L

    2004-08-01

    Previous research has documented high rates of STDs and increased risk of HIV infection among female sex workers (FSWs) in Mexico; however, little is known about the sexual risk behaviors of this population. The purpose of this study was to explore work history, context of sex work, sexual risk practices, client characteristics, attitudes toward condoms, and potential barriers to condom use in a sample of FSWs in Tijuana, Mexico. Analysis of qualitative data from 25 FSWs revealed that most women entered the sex trade at a young age ( M = 23 years), primarily as a result of financial need. Forty percent were single mothers supporting children. Women worked an average of 6-7 days per week; work shifts ranged from 4 to 13 hr per day. Clients were both Mexican and foreign (mostly American and Asian), and ranged in age from 18 to 80 years. Positive aspects of the job included flexible work hours and good income. Negative aspects of sex work included risks associated with physical assault, diseases, and unwanted pregnancies. Most clients did not want to use a condom and many offered additional money for unprotected sex. FSWs did not like to use condoms because they were perceived as uncomfortable. Most FSWs did not negotiate the use of condoms, had a low knowledge regarding the proper use of condoms, and were reticent to report their own unsafe sex practices. These results suggest the need to develop culturally appropriate safer sex interventions for FSWs in Mexican border cities.

  13. Sex-chromosome turnovers induced by deleterious mutation load.

    PubMed

    Blaser, Olivier; Grossen, Christine; Neuenschwander, Samuel; Perrin, Nicolas

    2013-03-01

    In sharp contrast with mammals and birds, many cold-blooded vertebrates present homomorphic sex chromosomes. Empirical evidence supports a role for frequent turnovers, which replace nonrecombining sex chromosomes before they have time to decay. Three main mechanisms have been proposed for such turnovers, relying either on neutral processes, sex-ratio selection, or intrinsic benefits of the new sex-determining genes (due, e.g., to linkage with sexually antagonistic mutations). Here, we suggest an additional mechanism, arising from the load of deleterious mutations that accumulate on nonrecombining sex chromosomes. In the absence of dosage compensation, this load should progressively lower survival rate in the heterogametic sex. Turnovers should occur when this cost outweighs the benefits gained from any sexually antagonistic genes carried by the nonrecombining sex chromosome. We use individual-based simulations of a Muller's ratchet process to test this prediction, and investigate how the relevant parameters (effective population size, strength and dominance of deleterious mutations, size of nonrecombining segment, and strength of sexually antagonistic selection) are expected to affect the rate of turnovers. PMID:23461315

  14. Developmental synergism of steroidal estrogens in sex determination.

    PubMed Central

    Bergeron, J M; Willingham, E; Osborn, C T; Rhen, T; Crews, D

    1999-01-01

    Gonadal sex in the red-eared slider turtle, Trachemys scripta, is determined by incubation temperature during embryonic development. Evidence suggests that temperature determines sex by influencing steroid hormone metabolism and/or sensitivity: steroidogenic enzyme inhibitors or exogenous sex steroid hormones and their man-made analogs override (or enhance) temperature effects on sex determination. Specifically, nonaromatizable androgens and aromatase inhibitors induce testis differentiation at female-producing temperatures, whereas aromatizable androgens and estrogens induce ovary differentiation at male-producing temperatures. Moreover, natural estrogens and temperature synergize to produce more females than would be expected if estrogens and temperature had purely additive effects on sex determination. In this study, we use sex reversal of turtle embryos incubated at a male-producing temperature to examine synergism among steroidal estrogens: estrone, 17ss-estradiol, and estriol. A low dose of 17ss-estradiol (200 ng) showed significant synergism when administered with a single low dose of estriol (10 ng). Likewise, a single low dose of estrone (250 ng) had a synergistic effect when combined with the same low dose of estriol (10 ng). We conclude that the weak natural estrogens estrone and 17ss-estradiol synergize with a low dose of the more potent estriol to reverse gonadal sex during the critical period of sexual differentiation. These results suggest that weak environmental estrogens may also synergize with stronger natural estrogens. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:9924002

  15. Genetics of cardiovascular disease: Importance of sex and ethnicity.

    PubMed

    Winham, Stacey J; de Andrade, Mariza; Miller, Virginia M

    2015-07-01

    Sex differences in incidence and prevalence of and morbidity and mortality from cardiovascular disease are well documented. However, many studies examining the genetic basis for cardiovascular disease fail to consider sex as a variable in the study design, in part, because there is an inherent difficulty in studying the contribution of the sex chromosomes in women due to X chromosome inactivation. This paper will provide general background on the X and Y chromosomes (including gene content, the pseudoautosomal regions, and X chromosome inactivation), discuss how sex chromosomes have been ignored in Genome-wide Association Studies (GWAS) of cardiovascular diseases, and discuss genetics influencing development of cardiovascular risk factors and atherosclerosis with particular attention to carotid intima-medial thickness, and coronary arterial calcification based on sex-specific studies. In addition, a brief discussion of how ethnicity and hormonal status act as confounding variables in sex-based analysis will be considered along with methods for statistical analysis to account for sex in cardiovascular disease.

  16. Genetics of cardiovascular disease: importance of sex and ethnicity

    PubMed Central

    Winham, Stacey J.; de Andrade, Mariza; Miller, Virginia M.

    2015-01-01

    Sex differences in incidence and prevalence of and morbidity and mortality from cardiovascular disease are well documented. However, many studies examining the genetic basis for cardiovascular disease fail to consider sex as a variable in the study design, in part, because there is an inherent difficulty in studying the contribution of the sex chromosomes in women due to X chromosome inactivation. This paper will provide general background on the X and Y chromosomes (including gene content, the pseudoautosomal regions, and X chromosome inactivation), discuss how sex chromosomes have been ignored in Genome-wide Association Studies (GWAS) of cardiovascular diseases, and discuss genetics influencing development of cardiovascular risk factors and atherosclerosis with particular attention to carotid intima-medial thickness, and coronary arterial calcification based on sex-specific studies. In addition, a brief discussion of how ethnicity and hormonal status act as confounding variables in sex-based analysis will be considered along with methods for statistical analysis to account for sex in cardiovascular disease. PMID:25817330

  17. Do Psychological Sex Differences Reflect Evolutionary Bisexual Partitioning?

    PubMed

    Trofimova, Irina

    2015-01-01

    This article analyzes sex differences in communicative and exploratory abilities and mental disabilities from the rarely discussed perspective of sex differences in the shape of phenotypic distributions. The article reviews the most consistent findings related to such differences and compares them with the evolutionary theory of sex (ETS). The ETS considers sexual dimorphism as a functional specialization of a species into 2 partitions: variational and conservational. The analysis suggests that male superiority in risk and sensation seeking and physical abilities; higher rates of psychopathy, dyslexia, and autism; and higher birth and accidental death rates reflects the systemic variational function of the male sex. Female superiority in verbal abilities, lawfulness, socialization, empathy, and agreeableness is presented as a reflection of the systemic conservational function of the female sex. From this perspective psychological sex differences in communicative and exploratory abilities might not just be an accidental result of sexual selection or labor distribution in early humans. It might reflect a global functional differentiation tendency within a species to expand its phenotypic diversity and at the same time to conserve beneficial features in the species' behavior. The article also offers an addition to the ETS by suggesting that the male sex (variable partition) plays an evolutionary role in pruning of the redundant excesses in a species' bank of beneficial characteristics despite resistance from the conservational partition. PMID:26721176

  18. Steroid signaling activation and intracellular localization of sex steroid receptors.

    PubMed

    Giraldi, Tiziana; Giovannelli, Pia; Di Donato, Marzia; Castoria, Gabriella; Migliaccio, Antimo; Auricchio, Ferdinando

    2010-12-01

    In addition to stimulating gene transcription, sex steroids trigger rapid, non-genomic responses in the extra-nuclear compartment of target cells. These events take place within seconds or minutes after hormone administration and do not require transcriptional activity of sex steroid receptors. Depending on cell systems, activation of extra-nuclear signaling pathways by sex steroids fosters cell cycle progression, prevents apoptosis, leads to epigenetic modifications and increases cell migration through cytoskeleton changes. These findings have raised the question of intracellular localization of sex steroid receptors mediating these responses. During the past years, increasing evidence has shown that classical sex steroid receptors localized in the extra-nuclear compartment or close to membranes of target cells induce these events. The emerging picture is that a process of bidirectional control between signaling activation and sex steroid receptor localization regulates the outcome of hormonal responses in target cells. This mechanism ensures cell cycle progression in estradiol-treated breast cancer cells, and its derangement might occur in progression of human proliferative diseases. These findings will be reviewed here together with unexpected examples of the relationship between sex steroid receptor localization, signaling activation and biological responses in target cells. We apologize to scientists whose reports are not mentioned or extensively discussed owing to space limitations.

  19. Territory Quality and Plumage Morph Predict Offspring Sex Ratio Variation in a Raptor

    PubMed Central

    Chakarov, Nayden; Pauli, Martina; Mueller, Anna-Katharina; Potiek, Astrid; Grünkorn, Thomas; Dijkstra, Cor; Krüger, Oliver

    2015-01-01

    Parents may adapt their offspring sex ratio in response to their own phenotype and environmental conditions. The most significant causes for adaptive sex-ratio variation might express themselves as different distributions of fitness components between sexes along a given variable. Several causes for differential sex allocation in raptors with reversed sexual size dimorphism have been suggested. We search for correlates of fledgling sex in an extensive dataset on common buzzards Buteo buteo, a long-lived bird of prey. Larger female offspring could be more resource-demanding and starvation-prone and thus the costly sex. Prominent factors such as brood size and laying date did not predict nestling sex. Nonetheless, lifetime sex ratio (LSR, potentially indicative of individual sex allocation constraints) and overall nestling sex were explained by territory quality with more females being produced in better territories. Additionally, parental plumage morphs and the interaction of morph and prey abundance tended to explain LSR and nestling sex, indicating local adaptation of sex allocation However, in a limited census of nestling mortality, not females but males tended to die more frequently in prey-rich years. Also, although females could have potentially longer reproductive careers, a subset of our data encompassing full individual life histories showed that longevity and lifetime reproductive success were similarly distributed between the sexes. Thus, a basis for adaptive sex allocation in this population remains elusive. Overall, in common buzzards most major determinants of reproductive success appeared to have no effect on sex ratio but sex allocation may be adapted to local conditions in morph-specific patterns. PMID:26445010

  20. Differential selection between the sexes and selection for sex.

    PubMed

    Roze, Denis; Otto, Sarah P

    2012-02-01

    Anisogamy is known to generate an important cost for sexual reproduction (the famous "twofold cost of sex"). However, male-female differences may have other consequences on the evolution of sex, due to the fact that selective pressures may differ among the sexes. On the one hand, intralocus sexual conflict should favor asexual females, which can fix female-beneficial, male-detrimental alleles. On the other hand, it has been suggested repeatedly that sexual selection among males may help to purge the mutation load, providing an advantage to sexual females. However, no analytical model has computed the strength of selection acting on a modifier gene affecting the frequency of sexual reproduction when selection differs between the sexes. In this article, we analyze a two-locus model using two approaches: a quasi-linkage-equilibrium (QLE) analysis and a local stability analysis, whose predictions are verified using a multilocus simulation. We find that costly sex can be maintained when selection is stronger in males than in females, but acts in the same direction in both. Complete asexuality, however, evolves under any other form of selection. Finally, we discuss how experimental measurements of fitness variances and covariances between sexes could be used to determine the overall direction and strength on selection for sex arising from differences in selection between males and females.

  1. [Neuroendocrine effect of sex hormones].

    PubMed

    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.

  2. Sex-Role Contravention and Sex Education Directed toward Young Children in Sweden.

    ERIC Educational Resources Information Center

    McConaghy, Maureen J.

    1979-01-01

    Sweden's sex-role ideology and policy of counteracting sex-role learning through the schools are described. Correspondence between policy and practice is reported. Parents tended to affirm some non-sex-determined standards, while reinforcing sex-typed behavior more than cross-sex-typed behavior. Most teachers made efforts to counteract sex roles.…

  3. Risk Comparison among Youth Who Report Sex with Same-Sex versus Both-Sex Partners

    ERIC Educational Resources Information Center

    Moon, Martha W.; Fornili, Katherine; O'Briant, Amanda L.

    2007-01-01

    This article examines risk behavior among youth attending support groups for sexual minority youth in Richmond, Virginia, using a structured survey, with particular attention to partner selection and its relationship to risk. Within this generally high-risk group, youth reporting sex partners of both sexes had significantly higher risk profiles,…

  4. Talk to Your Kids about Sex

    MedlinePlus

    ... Topic En español Talk to Your Kids about Sex Browse Sections The Basics Overview When to Start ... healthy expectations for their relationships. Talk about opposite-sex (straight) and same-sex (gay or lesbian) relationships. ...

  5. Sex and Psychological Differentiation in Preschoolers

    ERIC Educational Resources Information Center

    Domash, Leanne; Balter, Lawrence

    1976-01-01

    Examined the relationship between selected maternal attitudes and the sex, sex role preference and level of psychological differentiation of the preschool child. Data indicate that extreme sex role typing works against learning. (GO)

  6. [Sex education and population policies].

    PubMed

    Rodriguez, G

    1991-01-01

    Controversy about sex education programs has hampered sustained actin or curricular extension in Mexico beyond programs directly related to demographic policies. The 1st sex education in Mexico perhaps dated back to 1908 when physicians and other health professionals, inspired by the eugenics movement, offered sex education to prevent venereal diseases and maternal and/infant mortality. A 2nd attempt occurred in 1916 in the context of the women's suffrage movement. The 2 perspectives were integrated in a sex education project in 1933, as part of the program of "revolutionary education" legitimized by the progressive and modernizing government of the time. Conservative groups including some parents' associations and religious organizations insisted on their exclusive right to provide sex education, and in following decades they opposed social programs related to primary health care and women's rights. In the 1960, the introduction to Mexico of modern contraceptives and the questioning by young people of virginity and the double standard of sexual morality were not aided by any formal program of sex education in Mexico. In the early 1970s, the need to transform fertility patterns led to establishment of formal sex education programs at the national level. The focus was on reproduction and demographic aspects. Most students were exposed to classes and textbooks covering puberty, human reproduction, contraception, and sexually transmitted diseases. The intense activity of the early years did not continue in the subsequent program, but currently, the threat of AIDS and economic and social pressures are prompting a new political will in favor of sex education. Sex education is seen as the main strategy for AIDS prevention programs. Homosexual groups are demonstrating a new political pressure as civil organizations integrated into a new sector demanding sex education. At the same time, population policies are assuming a predominant position in official discourse as a

  7. [Sex education and population policies].

    PubMed

    Rodriguez, G

    1991-01-01

    Controversy about sex education programs has hampered sustained actin or curricular extension in Mexico beyond programs directly related to demographic policies. The 1st sex education in Mexico perhaps dated back to 1908 when physicians and other health professionals, inspired by the eugenics movement, offered sex education to prevent venereal diseases and maternal and/infant mortality. A 2nd attempt occurred in 1916 in the context of the women's suffrage movement. The 2 perspectives were integrated in a sex education project in 1933, as part of the program of "revolutionary education" legitimized by the progressive and modernizing government of the time. Conservative groups including some parents' associations and religious organizations insisted on their exclusive right to provide sex education, and in following decades they opposed social programs related to primary health care and women's rights. In the 1960, the introduction to Mexico of modern contraceptives and the questioning by young people of virginity and the double standard of sexual morality were not aided by any formal program of sex education in Mexico. In the early 1970s, the need to transform fertility patterns led to establishment of formal sex education programs at the national level. The focus was on reproduction and demographic aspects. Most students were exposed to classes and textbooks covering puberty, human reproduction, contraception, and sexually transmitted diseases. The intense activity of the early years did not continue in the subsequent program, but currently, the threat of AIDS and economic and social pressures are prompting a new political will in favor of sex education. Sex education is seen as the main strategy for AIDS prevention programs. Homosexual groups are demonstrating a new political pressure as civil organizations integrated into a new sector demanding sex education. At the same time, population policies are assuming a predominant position in official discourse as a

  8. Bayesian Reconstruction of Two-Sex Populations by Age: Estimating Sex Ratios at Birth and Sex Ratios of Mortality1

    PubMed Central

    Wheldon, Mark C.; Raftery, Adrian E.; Clark, Samuel J.; Gerland, Patrick

    2014-01-01

    Summary The original version of Bayesian reconstruction, a method for estimating age-specific fertility, mortality, migration and population counts of the recent past with uncertainty, produced estimates for female-only populations. Here we show how two-sex populations can be similarly reconstructed and probabilistic estimates of various sex ratio quantities obtained. We demonstrate the method by reconstructing the populations of India from 1971 to 2001, Thailand from 1960 to 2000, and Laos from 1985 to 2005. We found evidence that in India, sex ratio at birth exceeded its conventional upper limit of 1.06, and, further, increased over the period of study, with posterior probability above 0.9. In addition, almost uniquely, we found evidence that life expectancy at birth (e0) was lower for females than for males in India (posterior probability for 1971–1976 equal to 0.79), although there was strong evidence for a narrowing of the gap through to 2001. In both Thailand and Laos, we found strong evidence for the more usual result that e0 was greater for females and, in Thailand, that the difference increased over the period of study. PMID:26612972

  9. Studying both sexes: a guiding principle for biomedicine.

    PubMed

    Clayton, Janine Austin

    2016-02-01

    In May 2014, the U.S. National Institutes of Health (NIH) announced that it will ensure that investigators account for sex as a biological variable (SABV) in NIH-funded preclinical research as part of the agency's rigor and transparency initiative. Herein, I describe in more detail the rationale behind the SABV policy component and provide additional detail about policy goals. In short, studying both sexes is a guiding principle in biomedical research that will expand knowledge toward turning discovery into health. NIH expects that considering SABV in preclinical research will help to build a knowledge base that better informs the design of clinical research and trials in humans. Integrating the practice of studying both sexes in preclinical research will, over time, expand our currently incomplete knowledge base that plays a critical role in informing the development of sex- and gender-appropriate medical care for women and men.

  10. A sex difference in visual influence on heard speech.

    PubMed

    Irwin, Julia R; Whalen, D H; Fowler, Carol A

    2006-05-01

    Reports of sex differences in language processing are inconsistent and are thought to vary by task type and difficulty. In two experiments, we investigated a sex difference in visual influence onheard speech (the McGurk effect). First, incongruent consonant-vowel stimuli were presented where the visual portion of the signal was brief (100 msec) or full (temporally equivalent to the auditory). Second, to determine whether men and women differed in their ability to extract visual speech information from these brief stimuli, the same stimuli were presented to new participants with an additional visual-only (lipread) condition. In both experiments, women showed a significantly greater visual influence on heard speech than did men for the brief visual stimuli. No sex differences for the full stimuli or in the ability to lipread were found. These findings indicate that the more challenging brief visual stimuli elicit sex differences in the processing of audiovisual speech.

  11. Evaluation of PCR-based beef sexing methods.

    PubMed

    Zeleny, Reinhard; Bernreuther, Alexander; Schimmel, Heinz; Pauwels, Jean

    2002-07-17

    Analysis of the sex of beef meat by fast and reliable molecular methods is an important measure to ensure correct allocation of export refunds, which are considerably higher for male beef meat. Two PCR-based beef sexing methods have been optimized and evaluated. The amelogenin-type method revealed excellent accuracy and robustness, whereas the bovine satellite/Y-chromosome duplex PCR procedure showed more ambiguous results. In addition, an interlaboratory comparison was organized to evaluate currently applied PCR-based sexing methods in European customs laboratories. From a total of 375 samples sent out, only 1 false result was reported (female identified as male). However, differences in the performances of the applied methods became apparent. The collected data contribute to specify technical requirements for a common European beef sexing methodology based on PCR. PMID:12105941

  12. What Asexuality Contributes to the Same-Sex Marriage Discussion

    PubMed Central

    Scherrer, Kristin S.

    2010-01-01

    While same-sex marriage debates have captured public attention, it is but one component of a broader discussion regarding the role of marriage in a changing society. To inform this discussion, I draw on qualitative, Internet survey data from 102 self-identified asexual individuals. I find that asexual relationships are complicated and nuanced in ways that have implications for a GLBTQ political agenda, including same-sex marriage recognition. In addition, findings indicate that assumptions of sex and sexuality in relationships are problematic and that present language for describing relationships is limiting. Findings suggest a social justice agenda for marginalized sexualities should be broader in scope than same-sex marriage. PMID:20596244

  13. Same-sex marriage: a new social phenomenon.

    PubMed

    Chamie, Joseph; Mirkin, Barry

    2011-01-01

    Same-sex marriage (SSM) is a new social phenomenon. In modern times SSM did not exist until the 21st century when an increasing number of countries began permitting same-sex couples to marry legally. This study presents statistical and related evidence concerning SSM worldwide, with special attention to the United States, where SSM has evolved into a major political and legal issue. In addition to examining data on levels and trends, differentials between men and women are investigated. The study also considers common arguments for and against SSM and likely changes in laws and policies that may occur. Although same-sex marriage now exists in a small number of countries and US states, its consequences and implications are being felt far beyond the borders of those countries and areas. In coming years same-sex marriage will remain a controversial and salient part of the legal, political, and cultural landscape, locally, nationally, and internationally.

  14. Same-sex marriage: a new social phenomenon.

    PubMed

    Chamie, Joseph; Mirkin, Barry

    2011-01-01

    Same-sex marriage (SSM) is a new social phenomenon. In modern times SSM did not exist until the 21st century when an increasing number of countries began permitting same-sex couples to marry legally. This study presents statistical and related evidence concerning SSM worldwide, with special attention to the United States, where SSM has evolved into a major political and legal issue. In addition to examining data on levels and trends, differentials between men and women are investigated. The study also considers common arguments for and against SSM and likely changes in laws and policies that may occur. Although same-sex marriage now exists in a small number of countries and US states, its consequences and implications are being felt far beyond the borders of those countries and areas. In coming years same-sex marriage will remain a controversial and salient part of the legal, political, and cultural landscape, locally, nationally, and internationally. PMID:22167814

  15. The use of the sex pheromone as an evolutionary solution to food source selection in caterpillars.

    PubMed

    Poivet, Erwan; Rharrabe, Kacem; Monsempes, Christelle; Glaser, Nicolas; Rochat, Didier; Renou, Michel; Marion-Poll, Frédéric; Jacquin-Joly, Emmanuelle

    2012-01-01

    Sex pheromones are released by adults of a species to elicit a sexual interaction with the other sex of the same species. Here we report an unexpected effect of a moth sex pheromone on the caterpillars of the same species. We demonstrate that larvae of the cotton leafworm Spodoptera littoralis are attracted by the moth sex pheromone and that this phenomenon is independent of sex determination. In addition, we show that the olfactory sensilla carried by the caterpillar antennae are sensitive to the pheromone and that the caterpillar sensilla express pheromone-binding proteins that are used by adult antennae to bind pheromone components. Finally, we demonstrate that the larvae are preferentially attracted to a food source when it contains the sex pheromone main component. A possible interpretation of these results is that the sex pheromone is used to promote food search in caterpillars, opening potential new routes for insect pest management.

  16. Sex differences in the mechanisms underlying long QT syndrome.

    PubMed

    Salama, Guy; Bett, Glenna C L

    2014-09-01

    Sexual dimorphism is a well-established phenomenon, but its degree varies tremendously among species. Since the early days of Einthoven's development of the three-lead galvanometer ECG, we have known there are marked differences in QT intervals of men and women. It required over a century to appreciate the profound implications of sex-based electrophysiological differences in QT interval on the panoply of sex differences with respect to arrhythmia risk, drug sensitivity, and treatment modalities. Little is known about the fundamental mechanism responsible for sex differences in electrical substrate of the human heart, in large part due to the lack of tissue availability. Animal models are an important research tool, but species differences in the sexual dimorphism of the QT interval, the ionic currents underlying the cardiac repolarization, and effects of sex steroids make it difficult to interpolate animal to human sex differences. In addition, in some species, different strains of the same animal model yield conflicting data. Each model has its strengths, such as ease of genetic manipulation in mice or size in dogs. However, many animals do not reproduce the sexual dimorphism of QT seen in humans. To match sex linked prolongation of QT interval and arrhythmogenic phenotype, the current data suggest that the rabbit may be best suited to provide insight into sex differences in humans. In the future, emerging technologies such as induced pluripotent stem cell derived cardiac myocyte systems may offer the opportunity to study sex differences in a controlled hormonal situation in the context of a sex specific human model system.

  17. Sex differences in the mechanisms underlying long QT syndrome.

    PubMed

    Salama, Guy; Bett, Glenna C L

    2014-09-01

    Sexual dimorphism is a well-established phenomenon, but its degree varies tremendously among species. Since the early days of Einthoven's development of the three-lead galvanometer ECG, we have known there are marked differences in QT intervals of men and women. It required over a century to appreciate the profound implications of sex-based electrophysiological differences in QT interval on the panoply of sex differences with respect to arrhythmia risk, drug sensitivity, and treatment modalities. Little is known about the fundamental mechanism responsible for sex differences in electrical substrate of the human heart, in large part due to the lack of tissue availability. Animal models are an important research tool, but species differences in the sexual dimorphism of the QT interval, the ionic currents underlying the cardiac repolarization, and effects of sex steroids make it difficult to interpolate animal to human sex differences. In addition, in some species, different strains of the same animal model yield conflicting data. Each model has its strengths, such as ease of genetic manipulation in mice or size in dogs. However, many animals do not reproduce the sexual dimorphism of QT seen in humans. To match sex linked prolongation of QT interval and arrhythmogenic phenotype, the current data suggest that the rabbit may be best suited to provide insight into sex differences in humans. In the future, emerging technologies such as induced pluripotent stem cell derived cardiac myocyte systems may offer the opportunity to study sex differences in a controlled hormonal situation in the context of a sex specific human model system. PMID:24973386

  18. Sex Differences in Frailty.

    PubMed

    Hubbard, Ruth E

    2015-01-01

    Although women live longer lives than men, they tend to have poorer health status. Here, we review the biological and socio-behavioral factors that may contribute to this sex-frailty paradox. The conceptual framework that frailty is a product of the environment and the recovery rate provides a new understanding of women's frailty burden. Even developed countries may present an environment more adverse for women, and lifestyle factors may increase women's vulnerability to stochastic subcellular events that increase recovery time. The frailty index does not reach the theoretical maximal value of 1; its limit is lower in men (0.61) compared to women (0.69). Perhaps deterministic characteristics omitted in current deficit counts, such as reduced emotional adaptability, are more prevalent in men. Alternatively, different limits may result from quantitative evolutionary design, such as a fitness-frailty pleiotropy in men or fertility-frailty pleiotropy in women. The engineering principle of safety factors (maximal capacity divided by routine functioning) may also be informative. If the human system has the same safety factor as its organs (approximately 2.5), men may be 'calibrated' around a frailty index of 0.244, compared to 0.276 for women. Because 0.25 represents the tipping point between functional independence and reliance on others, evolutionary design may have allowed for some limited dependence in women, perhaps motivated by the perinatal period. PMID:26301978

  19. Sex Determination: Separate Sexes Are a Double Turnoff in Melons.

    PubMed

    Ma, Wen-Juan; Pannell, John R

    2016-02-22

    Flowers with only one sexual function typically result from the developmental suppression of the other. A recent study that shows how this is achieved has important implications for models of the evolution of separate sexes in plants.

  20. Sex Determination: Separate Sexes Are a Double Turnoff in Melons.

    PubMed

    Ma, Wen-Juan; Pannell, John R

    2016-02-22

    Flowers with only one sexual function typically result from the developmental suppression of the other. A recent study that shows how this is achieved has important implications for models of the evolution of separate sexes in plants. PMID:26906490

  1. Sex allocation and secondary sex ratio in Cuban boa (Chilabothrus angulifer): mother's body size affects the ratio between sons and daughters.

    PubMed

    Frynta, Daniel; Vejvodová, Tereza; Šimková, Olga

    2016-06-01

    Secondary sex ratios of animals with genetically determined sex may considerably deviate from equality. These deviations may be attributed to several proximate and ultimate factors. Sex ratio theory explains some of them as strategic decisions of mothers improving their fitness by selective investment in sons or daughters, e.g. local resource competition hypothesis (LRC) suggests that philopatric females tend to produce litters with male-biased sex ratios to avoid future competition with their daughters. Until now, only little attention has been paid to examine predictions of sex ratio theory in snakes possessing genetic sex determination and exhibiting large variance in allocation of maternal investment. Cuban boa is an endemic viviparous snake producing large-bodied newborns (∼200 g). Extremely high maternal investment in each offspring increases importance of sex allocation. In a captive colony, we collected breeding records of 42 mothers, 62 litters and 306 newborns and examined secondary sex ratios (SR) and sexual size dimorphism (SSD) of newborns. None of the examined morphometric traits of neonates appeared sexually dimorphic. The sex ratio was slightly male biased (174 males versus 132 females) and litter sex ratio significantly decreased with female snout-vent length. We interpret this relationship as an additional support for LRC as competition between mothers and daughters increases with similarity of body sizes between competing snakes.

  2. Sex allocation and secondary sex ratio in Cuban boa ( Chilabothrus angulifer): mother's body size affects the ratio between sons and daughters

    NASA Astrophysics Data System (ADS)

    Frynta, Daniel; Vejvodová, Tereza; Šimková, Olga

    2016-06-01

    Secondary sex ratios of animals with genetically determined sex may considerably deviate from equality. These deviations may be attributed to several proximate and ultimate factors. Sex ratio theory explains some of them as strategic decisions of mothers improving their fitness by selective investment in sons or daughters, e.g. local resource competition hypothesis (LRC) suggests that philopatric females tend to produce litters with male-biased sex ratios to avoid future competition with their daughters. Until now, only little attention has been paid to examine predictions of sex ratio theory in snakes possessing genetic sex determination and exhibiting large variance in allocation of maternal investment. Cuban boa is an endemic viviparous snake producing large-bodied newborns (˜200 g). Extremely high maternal investment in each offspring increases importance of sex allocation. In a captive colony, we collected breeding records of 42 mothers, 62 litters and 306 newborns and examined secondary sex ratios (SR) and sexual size dimorphism (SSD) of newborns. None of the examined morphometric traits of neonates appeared sexually dimorphic. The sex ratio was slightly male biased (174 males versus 132 females) and litter sex ratio significantly decreased with female snout-vent length. We interpret this relationship as an additional support for LRC as competition between mothers and daughters increases with similarity of body sizes between competing snakes.

  3. Sex allocation and secondary sex ratio in Cuban boa (Chilabothrus angulifer): mother's body size affects the ratio between sons and daughters.

    PubMed

    Frynta, Daniel; Vejvodová, Tereza; Šimková, Olga

    2016-06-01

    Secondary sex ratios of animals with genetically determined sex may considerably deviate from equality. These deviations may be attributed to several proximate and ultimate factors. Sex ratio theory explains some of them as strategic decisions of mothers improving their fitness by selective investment in sons or daughters, e.g. local resource competition hypothesis (LRC) suggests that philopatric females tend to produce litters with male-biased sex ratios to avoid future competition with their daughters. Until now, only little attention has been paid to examine predictions of sex ratio theory in snakes possessing genetic sex determination and exhibiting large variance in allocation of maternal investment. Cuban boa is an endemic viviparous snake producing large-bodied newborns (∼200 g). Extremely high maternal investment in each offspring increases importance of sex allocation. In a captive colony, we collected breeding records of 42 mothers, 62 litters and 306 newborns and examined secondary sex ratios (SR) and sexual size dimorphism (SSD) of newborns. None of the examined morphometric traits of neonates appeared sexually dimorphic. The sex ratio was slightly male biased (174 males versus 132 females) and litter sex ratio significantly decreased with female snout-vent length. We interpret this relationship as an additional support for LRC as competition between mothers and daughters increases with similarity of body sizes between competing snakes. PMID:27216175

  4. Seeking sex partners through the internet and mobile phone applications among men who have sex with men in Taiwan.

    PubMed

    Ko, Nai-Ying; Tseng, Po-Chia; Huang, Yu-Chao; Chen, Yen-Chin; Hsu, Su-Ting

    2016-07-01

    It has become popular for men who have sex with men (MSM) to use mobile-phone geosocial networking applications (mobile apps) to find sex partners. A cross-sectional online survey was conducted in Taiwan to compare the sexual and substance-use behaviors of MSM seeking sex partners through the internet and mobile apps. Of the 1060 participants, 65.8% used the internet via computer and 37.7% used a mobile app to find sexual partners, while 30.3% used recreational drugs or alcohol in the previous 6 months. MSM who exclusively used mobile apps to seek sex partners were significantly more likely than MSM seeking sex via computer to be older, to have used recreational drugs or alcohol, and to have sex with HIV-positive partners. Additionally, using mobile apps to seek sex partners was significantly associated with having sex with online partners through either mobile apps or computer-based internet use (adjusted odds ratio (AOR), 7.12 [3.87-13.11]), self-reporting as HIV-positive (AOR, 2.24 [1.12-4.12]), using recreational drugs (AOR, 1.67 [1.21-2.32]), having disclosed HIV status to sexual partners (AOR, 1.44 [1.03-2.02]), and having sex with HIV-positive partners (AOR, 1.81 [1.06-3.10]). In conclusion, the mobile apps may serve as a feasible platform for HIV-positive MSM to find other HIV-positive partners. PMID:26754350

  5. Seriously mentally ill women's safer sex behaviors and the theory of reasoned action.

    PubMed

    Randolph, Mary E; Pinkerton, Steven D; Somlai, Anton M; Kelly, Jeffrey A; McAuliffe, Timothy L; Gibson, Richard H; Hackl, Kristin

    2009-10-01

    Seriously mentally ill women at risk for HIV infection (n = 96) participated in structured interviews assessing sexual and substance-use behavior over a 3-month period. The majority of the women (63.5%) did not use condoms. Consistent with the theory of reasoned action, attitudes toward condom use and perceived social norms about safer sex were associated with safer sex intentions. Supplementing variables from the theory of reasoned action with safer sex self-efficacy explained additional variance in safer sex intentions. Greater safer sex intentions were related to both greater condom use and less frequent unprotected intercourse. In addition, less frequent sex after drug use and a less fatalistic outlook were associated with less frequent unprotected intercourse. Life circumstances specific to this population are particularly important to examine to improve the effectiveness of risk reduction interventions for seriously mentally ill women.

  6. The social dynamics of safe sex practices among Canadian sex industry clients.

    PubMed

    Atchison, Chris; Burnett, Patrick John

    2016-07-01

    Much of what we know about the safe sex practices of people who pay for sexual services (clients) remains firmly grounded in empirical and interpretive tendencies to overemphasise the causal link between social, cultural or individual characteristics and sexual decision-making. In this study we apply Adam Green's Bourdieu-inspired sexual fields theory to examine the ways in which safe sex practices are interdependently shaped by social, personal and interpersonal forces. Using data from 697 questionnaires and 24 semi-structured interviews with Canadian clients, we implemented a series of six additive logistic regression models and contextualised the results with the interview data to reveal the relational interdependencies of intra-psychic, macro, meso and micro-level factors related to safe sex practices. The questionnaire responses and interview data used in the study were gathered from a diverse sample of clients who were over the age of 19, had paid money for sexual services on one or more occasions during their lifetime and who resided in Canada at the time of participation. Our results illustrate the ways in which factors related to the venue where sexual acts take place, clients' relationships with commercial and non-commercial partners and personal choices related to substance use interdependently inform safe sex practices. PMID:27018404

  7. Why have sex? The population genetics of sex and recombination.

    PubMed

    Otto, S P; Gerstein, A C

    2006-08-01

    One of the greatest puzzles in evolutionary biology is the high frequency of sexual reproduction and recombination. Given that individuals surviving to reproductive age have genomes that function in their current environment, why should they risk shuffling their genes with those of another individual? Mathematical models are especially important in developing predictions about when sex and recombination can evolve, because it is difficult to intuit the outcome of evolution with several interacting genes. Interestingly, theoretical analyses have shown that it is often quite difficult to identify conditions that favour the evolution of high rates of sex and recombination. For example, fitness interactions among genes (epistasis) can favour sex and recombination but only if such interactions are negative, relatively weak and not highly variable. One reason why an answer to the paradox of sex has been so elusive is that our models have focused unduly on populations that are infinite in size, unstructured and isolated from other species. Yet most verbal theories for sex and recombination consider a finite number of genotypes evolving in a biologically and/or physically complex world. Here, we review various hypotheses for why sex and recombination are so prevalent and discuss theoretical results indicating which of these hypotheses is most promising.

  8. [Food additives and healthiness].

    PubMed

    Heinonen, Marina

    2014-01-01

    Additives are used for improving food structure or preventing its spoilage, for example. Many substances used as additives are also naturally present in food. The safety of additives is evaluated according to commonly agreed principles. If high concentrations of an additive cause adverse health effects for humans, a limit of acceptable daily intake (ADI) is set for it. An additive is a risk only when ADI is exceeded. The healthiness of food is measured on the basis of nutrient density and scientifically proven effects.

  9. Environmental sensitivity in relation to size and sex in birds: meta-regression analysis.

    PubMed

    Jones, Kristopher S; Nakagawa, Shinichi; Sheldon, Ben C

    2009-07-01

    Studies of animals often report a greater sensitivity of one sex to poor rearing environments. However, it is unclear whether size differences associated with sex, sex itself, or other factors are responsible for differences in performance. While the greater nutritional requirement of the larger sex is a plausible explanation for increased sensitivity (i.e., size-dependent vulnerability), other hypotheses suggest that size-independent traits may have effects on the fitness of offspring (i.e., sex-dependent vulnerability). For example, the heterogametic sex may be more vulnerable to expression of sex-linked recessives in poor environments, or sex-specific phenotypes may have negative effects (e.g., increased testosterone in males). We examined support for these hypotheses through the use of meta-analytic techniques based on the published literature on avian species. Our results revealed small, nonsignificant effects for hypotheses of size- and sex-dependent susceptibilities alone. Application of a multivariate meta-analytic technique (meta-regression) suggests a joint influence of sexual size dimorphism and clutch size in explaining sex-specific patterns of vulnerability. These findings suggest that none of the proposed hypotheses tested here on their own can sufficiently explain the observed patterns and that additional factors must be considered in order to explain the diversity of patterns of sex-specific sensitivity observed in the literature.

  10. Disentangling the benefits of sex.

    PubMed

    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.

  11. Sex, drugs and pain control

    PubMed Central

    Brings, Victoria E; Zylka, Mark J

    2015-01-01

    A study finds that pain hypersensitivity in male and female mice is differentially dependent on microglia and T cells, and describes a sex-specific response to microglia-targeted pain treatments. PMID:26216458

  12. Sex and the nursing home.

    PubMed

    Levine, Murray

    2016-01-01

    The current article discusses the case of Henry Rahons. A nearly 80 year old man who was accused by the local district attorney of having unlawful sexual contact with Donna, his second wife of some seven years who had developed Alzheimer's disease in her later years. Under Iowa law, he was accused of having sexually abused her because she had "a mental defect or incapacity which precludes giving consent" to sex acts. A jury acquitted Henry of the charge of sexually abusing his wife. The evidence was equivocal that a sex act occurred on May 23, 2014, the date specified in the indictment. This article addresses the ability to assessed competence to consent to sex in similar situations. The current rules and attitudes about senior sex in nursing homes needs to be reevaluated. (PsycINFO Database Record PMID:27196391

  13. Differential Freshman Admission by Sex

    ERIC Educational Resources Information Center

    Suddick, David E.; McBee, M. Louise

    1974-01-01

    The authors report on a study whose purpose was to determine if, after adjusting for initial differences in high school averages and SAT scores via separate regression equations, differential admissions criterion by sex is justifiable. No justification is found. (RP)

  14. Sex and the nursing home.

    PubMed

    Levine, Murray

    2016-01-01

    The current article discusses the case of Henry Rahons. A nearly 80 year old man who was accused by the local district attorney of having unlawful sexual contact with Donna, his second wife of some seven years who had developed Alzheimer's disease in her later years. Under Iowa law, he was accused of having sexually abused her because she had "a mental defect or incapacity which precludes giving consent" to sex acts. A jury acquitted Henry of the charge of sexually abusing his wife. The evidence was equivocal that a sex act occurred on May 23, 2014, the date specified in the indictment. This article addresses the ability to assessed competence to consent to sex in similar situations. The current rules and attitudes about senior sex in nursing homes needs to be reevaluated. (PsycINFO Database Record

  15. Sex and Violence in Neuroscience.

    ERIC Educational Resources Information Center

    Barnes, Deborah M.

    1988-01-01

    Describes advances made in the understanding of how sex hormones may modify various cognitive skills, how normal brain signaling mechanisms may cause nerve cell death, and how many cells appear to hold genetic agents which determine their own destruction. (RT)

  16. Classifying sex biased congenital anomalies

    SciTech Connect

    Lubinsky, M.S.

    1997-03-31

    The reasons for sex biases in congenital anomalies that arise before structural or hormonal dimorphisms are established has long been unclear. A review of such disorders shows that patterning and tissue anomalies are female biased, and structural findings are more common in males. This suggests different gender dependent susceptibilities to developmental disturbances, with female vulnerabilities focused on early blastogenesis/determination, while males are more likely to involve later organogenesis/morphogenesis. A dual origin for some anomalies explains paradoxical reductions of sex biases with greater severity (i.e., multiple rather than single malformations), presumably as more severe events increase the involvement of an otherwise minor process with opposite biases to those of the primary mechanism. The cause for these sex differences is unknown, but early dimorphisms, such as differences in growth or presence of H-Y antigen, may be responsible. This model provides a useful rationale for understanding and classifying sex-biased congenital anomalies. 42 refs., 7 tabs.

  17. Sharing dreams: sex and other sociodemographic variables.

    PubMed

    Schredl, Michael

    2009-08-01

    Dream sharing is a common experience for most people. Factors which might be related to dream sharing in a representative German sample were investigated in the present study. As expected, the frequency of positively toned and neutral dreams and the frequency of negatively toned dreams were related to dream sharing. In addition, an effect of sex was found: women shared their dreams more often than men. Dream sharing differing by social class and education might point to class-specific attitudes toward dreams which have not yet been studied in detail.

  18. Sex differences in human gregariousness

    PubMed Central

    Stella, Sandra; Ferranti, Anthony

    2015-01-01

    Research on human sociality rarely includes kinship, social structure, sex, and familiarity, even though these variables influence sociality in non-human primates. However, cross-cultural ethnographic and observational studies with humans indicate that, beginning after age 5 years, males and females form differing social structures with unrelated individuals in a community. Specifically, compared with females, human males exhibit greater tolerance for and form larger, interconnected groups of peers which we term “gregariousness.” To examine sex differences in gregariousness early in life when children first interact with peers without adult supervision, 3- to 6-year-old children were given the choice to enter one of three play areas: an empty one, one with an adult, or one with a familiar, same-sex peer. More males than females initially chose the play area with the same-sex peer, especially after age 5 years. Sex differences in gregariousness with same-sex peers likely constitute one facet of human sociality. PMID:26038729

  19. Storage of sexed boar spermatozoa: Limits and perspectives.

    PubMed

    Spinaci, M; Perteghella, S; Chlapanidas, T; Galeati, G; Vigo, D; Tamanini, C; Bucci, D

    2016-01-01

    Despite the great potential application of sex-sorted spermatozoa in swine, the technology is not practiced in the pig industry because of technical factors and species-specific issues. The susceptibility of boar spermatozoa to stresses induced by the sorting procedure, the relative slowness of the sex-sorting process together with the high sperm numbers required for routine artificial insemination in pig are some of the main factors limiting the commercial application of this technology in pigs. This review briefly describes the damage to spermatozoa during sex sorting, focusing on an additional limiting factor: increased susceptibility of sexed boar spermatozoa to injuries induced by liquid storage and cryopreservation that, in turn, impairs sperm quality leading to unsatisfactory results in vivo. Strategies to extend the lifespan of sex-sorted boar spermatozoa and to improve their fertilizing ability after liquid storage or cryopreservation need to be implemented before this technology can be used in pig farms. In this regard, encapsulation in barium alginate membranes could be a promising technique to optimize the in vivo use of sexed boar spermatozoa, by protecting, targeting, and controlling the release of sperm into the female genital tract. PMID:26116059

  20. Sex determination using metatarsal osteometrics from the Athens collection.

    PubMed

    Mountrakis, Constantine; Eliopoulos, Constantine; Koilias, Christos G; Manolis, Sotiris K

    2010-07-15

    The determination of sex in skeletal remains performed by forensic anthropologists or bioarchaeologists typically relies on the analysis of quantitative and qualitative characteristics of the skeleton. In this regard, the most widely used features belong to the pelvic and cranial areas, but these are often not available in forensic or archaeological contexts. The objective of this study is to determine the extent of dimorphism exhibited by the metatarsal bones in order to examine their utility in the metric determination of sex in skeletal remains of Greek origin. A further objective is the development of linear discriminant function equations for sex determination based on the metatarsals from a contemporary Greek population. The skeletal sample used in this study is comprised of 1595 metatarsals (left and right), corresponding to 186 adult individuals (97 males, 89 females) and belongs to the documented collection of the University of Athens. The results suggest that metatarsal bones exhibit significant sexual dimorphism and the accuracy of the discriminant function equations for sex determination range from 80.7% to 90.1% (or 77.9-86.4% cross-validated). Thus, metatarsal bones may be used for sex determination in skeletal remains from Greece in addition to other sexing techniques.

  1. Incubation temperature causes skewed sex ratios in a precocial bird.

    PubMed

    DuRant, Sarah E; Hopkins, William A; Carter, Amanda W; Kirkpatrick, Laila T; Navara, Kristin J; Hawley, Dana M

    2016-07-01

    Many animals with genetic sex determination are nonetheless capable of manipulating sex ratios via behavioral and physiological means, which can sometimes result in fitness benefits to the parent. Sex ratio manipulation in birds is not widely documented, and revealing the mechanisms for altered sex ratios in vertebrates remains a compelling area of research. Incubation temperature is a key component of the developmental environment for birds, but despite its well-documented effects on offspring phenotype it has rarely been considered as a factor in avian sex ratios. Using ecologically relevant manipulations of incubation temperature within the range 35.0-37.0°C, we found greater mortality of female embryos during incubation than males regardless of incubation temperature, and evidence that more female than male embryos die at the lowest incubation temperature (35.0°C). Our findings in conjunction with previous work in brush turkeys suggest incubation temperature is an important determinant of avian secondary sex ratios that requires additional study, and should be considered when estimating the impact of climate change on avian populations. PMID:27143750

  2. Size Matters: Cerebral Volume Influences Sex Differences in Neuroanatomy

    PubMed Central

    Towler, Stephen; Welcome, Suzanne; Halderman, Laura K.; Otto, Ron; Eckert, Mark A.; Chiarello, Christine

    2008-01-01

    Biological and behavioral differences between the sexes range from obvious to subtle or nonexistent. Neuroanatomical differences are particularly controversial, perhaps due to the implication that they might account for behavioral differences. In this sample of 200 men and women, large effect sizes (Cohen's d > 0.8) were found for sex differences in total cerebral gray and white matter, cerebellum, and gray matter proportion (women had a higher proportion of gray matter). The only one of these sex differences that survived adjustment for the effect of cerebral volume was gray matter proportion. Individual differences in cerebral volume accounted for 21% of the difference in gray matter proportion, while sex accounted for an additional 4%. The relative size of the corpus callosum was 5% larger in women, but this difference was completely explained by a negative relationship between relative callosal size and cerebral volume. In agreement with Jancke et al., individuals with higher cerebral volume tended to have smaller corpora callosa. There were few sex differences in the size of structures in Broca's and Wernicke's area. We conclude that individual differences in brain volume, in both men and women, account for apparent sex differences in relative size. PMID:18440950

  3. A Review of The Sex EDcyclopedia

    ERIC Educational Resources Information Center

    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…

  4. Genomic characterization of sex-identification markers in Sebastes carnatus and Sebastes chrysomelas rockfishes.

    PubMed

    Fowler, Benjamin L S; Buonaccorsi, Vincent P

    2016-05-01

    Fish have evolved a variety of sex-determining (SD) systems including male heterogamy (XY), female heterogamy (ZW) and environmental SD. Little is known about SD mechanisms of Sebastes rockfishes, a highly speciose genus of importance to evolutionary and conservation biology. Here, we characterize the sex determination system in the sympatrically distributed sister species Sebastes chrysomelas and Sebastes carnatus. To identify sex-specific genotypic markers, double digest restriction site - associated DNA sequencing (ddRAD-seq) of genomic DNA from 40 sexed individuals of both species was performed. Loci were filtered for presence in all of the individuals of one sex, absence in the other sex and no heterozygosity. Of the 74 965 loci present in all males, 33 male-specific loci met the criteria in at least one species and 17 in both. Conversely, no female-specific loci were detected, together providing evidence of an XY sex determination system in both species. When aligned to a draft reference genome from Sebastes aleutianus, 26 sex-specific loci were interspersed among 1168 loci that were identical between sexes. The nascent Y chromosome averaged 5% divergence from the X chromosome and mapped to reference Sebastes genome scaffolds totalling 6.9Mbp in length. These scaffolds aligned to a single chromosome in three model fish genomes. Read coverage differences were also detected between sex-specific and autosomal loci. A PCR-RFLP assay validated the bioinformatic results and correctly identified sex of five additional individuals of known sex. A sex-determining gene in other teleosts gonadal soma-derived factor (gsdf) was present in the model fish chromosomes that spanned our sex-specific markers. PMID:26923740

  5. A computational model for sex-specific genetic architecture of complex traits in humans: Implications for mapping pain sensitivity

    PubMed Central

    Wang, Chenguang; Cheng, Yun; Liu, Tian; Li, Qin; Fillingim, Roger B; Wallace, Margaret R; Staud, Roland; Kaplan, Lee; Wu, Rongling

    2008-01-01

    Understanding differences in the genetic architecture of complex traits between the two sexes has significant implications for evolutionary studies and clinical diagnosis. However, our knowledge about sex-specific genetic architecture is limited largely because of a lack of analytical models that can detect and quantify the effects of sex on the complexity of quantitative genetic variation. Here, we derived a statistical model for mapping DNA sequence variants that contribute to sex-specific differences in allele frequencies, linkage disequilibria, and additive and dominance genetic effects due to haplotype diversity. This model allows a genome-wide search for functional haplotypes and the estimation and test of haplotype by sex interactions and sex-specific heritability. The model, validated by simulation studies, was used to detect sex-specific functional haplotypes that encode a pain sensitivity trait in humans. The model could have important implications for mapping complex trait genes and studying the detailed genetic architecture of sex-specific differences. PMID:18416828

  6. Creating comprehensive, youth centered, culturally appropriate sex education: What do young gay, bisexual and questioning men want?

    PubMed Central

    Pingel, Emily Sweetnam; Thomas, Laura; Harmell, Chelsea; Bauermeister, José

    2013-01-01

    We examined young gay, bisexual and questioning men's (YGBQM) experiences with school-based sex education as they sought to learn about sex and sexual health, and their suggestions for improving same-sex education resources. Thematic analysis of 30 in-depth interviews with YGBQM (ages 18-24) underscored the discrepancies between the existing school-based sex education curricula and YGBQM's perceived sex education needs. Our results show that many youths' sexuality and same-sex sexual behaviors are excluded in sex education lessons; however, YGBQM noted that they sought out other resources (e.g., websites) to answer their questions. We discuss YGBQM's ideas for the creation of a sex and sexual health website that would be tailored for youth like themselves, including topics and features that an ideal website would contain. In addition, we present recommended changes to existing school-based sexual education curricula. PMID:24348222

  7. Meanings of sex, concepts of risk and sexual practices among migrant coal miners in Quang Ninh, Vietnam.

    PubMed

    Van Tuan, Ta

    2010-08-01

    The study explores the meanings of sex among migrant coal miners in Vietnam and identifies contextual factors influencing engagement in unsafe sexual practices. Findings reveal that sex carries a number of social meanings in the lives of migrant miners: sex is relaxation and reward for their risk and hard work; access to sex is an incentive for miners to continue working in the mine; sex strengthens identity and social networks; sex helps miners to affirm manhood, group membership and masculinity; and sex workers are confidants with whom they can share their problems. Facing accidents at work on a daily basis, miners are less inclined to worry about the long-term risks of HIV infection. In addition, being excluded from access to relevant information, miners feel distant from HIV infection. Findings suggest that interventions on sexual behaviour and practices should be sensitive to the concepts of risk and meanings of sex among migrant groups such as coal miners.

  8. Creating comprehensive, youth centered, culturally appropriate sex education: What do young gay, bisexual and questioning men want?

    PubMed

    Pingel, Emily Sweetnam; Thomas, Laura; Harmell, Chelsea; Bauermeister, José

    2013-12-01

    We examined young gay, bisexual and questioning men's (YGBQM) experiences with school-based sex education as they sought to learn about sex and sexual health, and their suggestions for improving same-sex education resources. Thematic analysis of 30 in-depth interviews with YGBQM (ages 18-24) underscored the discrepancies between the existing school-based sex education curricula and YGBQM's perceived sex education needs. Our results show that many youths' sexuality and same-sex sexual behaviors are excluded in sex education lessons; however, YGBQM noted that they sought out other resources (e.g., websites) to answer their questions. We discuss YGBQM's ideas for the creation of a sex and sexual health website that would be tailored for youth like themselves, including topics and features that an ideal website would contain. In addition, we present recommended changes to existing school-based sexual education curricula.

  9. Nuclear genes with sex bias in Ruditapes philippinarum (Bivalvia, veneridae): Mitochondrial inheritance and sex determination in DUI species.

    PubMed

    Milani, Liliana; Ghiselli, Fabrizio; Nuzhdin, Sergey V; Passamonti, Marco

    2013-11-01

    Mitochondria are inherited maternally in most metazoans, but in bivalves with Doubly Uniparental Inheritance (DUI) a mitochondrial lineage is transmitted through eggs (F-type), and another through sperm (M-type). In DUI species, a sex-ratio distortion of the progeny was observed: some females produce a female-biased offspring (female-biased family), others a male-biased progeny (male-biased family), and others a 50:50 sex-ratio. A peculiar segregation pattern of M-type mitochondria in DUI organisms appears to be correlated with the sex bias of these families. According to a proposed model for the inheritance of M-type mitochondria in DUI, the transmission of sperm mitochondria is controlled by three nuclear genes, named W, X, and Z. An additional S gene with different dosage effect would be involved in sex determination. In this study, we analyzed structure and localization of three transcripts (psa, birc, and anubl1) with specific sex and family biases in the Manila clam Ruditapes philippinarum. In situ hybridization confirmed the localization of these transcripts in gametogenic cells. In other animals, homologs of these genes are involved in reproduction and ubiquitination. We hypothesized that these genes may have a role in sex determination and could also be responsible for the maintenance/degradation of spermatozoon mitochondria during embryo development of the DUI species R. philippinarum, so that we propose them as candidate factors of the W/X/Z/S system.

  10. The ethics of safe sex.

    PubMed

    Broom, N D; Rickett, C E

    1988-12-14

    Western society has undergone a vast sociological change during the 20th century in terms of the value of sexuality. Sexual choice has gained a new legitimacy never before experienced. There is less guilt surrounding issues of sexuality and it is now common place to hear and see explicit discussions about sex in the mass media. This acceptance has undoubtedly encouraged many people to be more daring and promiscuous in their sexual activities. Proof of this can be seen in the increase is the incidence of sexually transmitted diseases (STDs). Presently there are more than 20 epidemiologically significant diseases that are sexually transmitted. Beyond the 5 old standards of gonorrhea, syphilis, chancroid, lyphogranuloma venereum, and granuloma inguinala STDs now include: chlamydia trachomatis, genital herpes, human papillomavirus, human immunodeficiency virus, genital mycoplasms, cytomegalovirus, hepatitis, vaginitis, enteric infections, and ectoparasitic diseases. Keeping all this in mind, the question of the ethics of safe sex must be addressed. In many countries, the governments have undertaken large public education programs to encourage safe sex practices. All these programs a founded upon two ideas: that safe sex should be promoted free of any ethical discussions or considerations, and that technology alone, the condom, will protect the public from the problem of STDs. However these campaigns will fail to protect the public unless they try to intervene at some level other than the mechanical aspect of the sex act itself. Condoms have failure rates too high to be relied upon as the sole means of protecting the public. Sex education for children and an inclusion of the ethical aspects of sex, now that the consequences can mean death, must be included in these government programs if they are to be successful.

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

    ERIC Educational Resources Information Center

    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…

  12. Recognize sex work as legitimate work.

    PubMed

    Reynaga, Elena

    2008-12-01

    It is not sex work per se that makes sex workers vulnerable to HIV, but rather the policies that repress them. In this article, based on her presentation at a plenary session at the conference, Elena Reynaga, who is a sex worker, describes how these policies deprive sex workers of their rights and subject them to physical and sexual violence. The author concludes that at the heart of the problem lies the fact that sex work is not recognized as legitimate work.

  13. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Fletcher, James C. (Inventor); Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1992-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  14. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1993-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of the additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  15. Sex hormone replacement in disorders of sex development.

    PubMed

    Birnbaum, Wiebke; Bertelloni, Silvano

    2014-01-01

    People with disorders of sex development (DSD) may have impaired sex steroid production or their gonads removed before, during or after adolescence, thus requiring hormone replacement therapy (HRT) to induce puberty and/or maintain secondary sexual characteristics, to optimize bone health, and to promote physical and social well-being. Oestrogens are usually used for this purpose in persons reared as females (eventually combined with progestins if a uterus is present) and androgens in those reared as males. An alternative therapy for women with ascertained complete androgen insensitivity syndrome could be testosterone, because this is the main sex steroid hormone secreted by their gonads, but this approach remains to be better explored. Few sound evidence-based data are available to guide HRT administration at puberty and in adulthood in individuals with DSD, but recent data and new formulations may give better perspectives for the future.

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

    PubMed

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

    2011-05-01

    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 characterised by major physical and behavioural transformations, it is unclear why the incidence of depression increases so dramatically in girls during this otherwise generally healthy developmental period. Although psychological and environmental factors are also involved, we discuss the neuroendocrinological factors determining adolescent vulnerability to depression. In particular, we address the role of sex steroids in mood regulation, hypothalamic-pituitary-adrenal axis maturation and sexual differentiation of the brain, with a focus on hippocampal plasticity.

  17. On Reconstructing School Segregation: The Efficacy and Equity of Single-Sex Schooling

    ERIC Educational Resources Information Center

    Billger, Sherrilyn M.

    2009-01-01

    A change to Title IX has spurred new single-sex public schooling in the US. Until recently, nearly all gender-segregated schools were private, and comprehensive data for public school comparisons are not yet available. To investigate the effects of single-sex education, I focus on within private sector comparisons, and additionally address…

  18. Promoting Sex Equity in the Classroom. Module 6, Agriculture. Revised, 1980.

    ERIC Educational Resources Information Center

    Iowa State Univ. of Science and Technology, Ames. Dept. of Home Economics Education.

    Designed to be used with modules 1 through 5, this sixth in a series of twelve modules presents sex equity teaching strategies unique to the agriculture classroom. Strategies are grouped by sex equity guideline categories: art, language, and content. In addition to specific strategies, instructional suggestions based on common strategies are…

  19. Female-only sex-linked amplified fragment length polymorphism markers support ZW/ZZ sex determination in the giant freshwater prawn Macrobrachium rosenbergii.

    PubMed

    Jiang, Xue-Hui; Qiu, Gao-Feng

    2013-12-01

    Sex determination mechanisms in many crustacean species are complex and poorly documented. In the giant freshwater prawn, Macrobrachium rosenbergii, a ZW/ZZ sex determination system was previously proposed based on sex ratio data obtained by crosses of sex-reversed females (neomales). To provide molecular evidence for the proposed system, novel sex-linked molecular markers were isolated in this species. Amplified fragment length polymorphism (AFLP) using 64 primer combinations was employed to screen prawn genomes for DNA markers linked with sex loci. Approximately 8400 legible fragments were produced, 13 of which were uniquely identified in female prawns with no indication of corresponding male-specific markers. These AFLP fragments were reamplified, cloned and sequenced, producing two reliable female-specific sequence characterized amplified region (SCAR) markers. Additional individuals from two unrelated geographic populations were used to verify these findings, confirming female-specific amplification of single bands. Detection of internal polymorphic sites was conducted by designing new primer pairs based on these internal fragments. The internal SCAR fragments also displayed specificity in females, indicating high levels of variation between female and male specimens. The distinctive feature of female-linked SCAR markers can be applied for rapid detection of prawn gender. These sex-specific SCAR markers and sex-associated AFLP candidates unique to female specimens support a sex determination system consistent with female heterogamety (ZW) and male homogamety (ZZ).

  20. Gender, sex hormones and pulmonary hypertension.

    PubMed

    Austin, Eric D; Lahm, Tim; West, James; Tofovic, Stevan P; Johansen, Anne Katrine; Maclean, Margaret R; Alzoubi, Abdallah; Oka, Masahiko

    2013-04-01

    Most subtypes of pulmonary arterial hypertension (PAH) are characterized by a greater susceptibility to disease among females, although females with PAH appear to live longer after diagnosis. While this "estrogen paradoxȍ of enhanced female survival despite increased female susceptibility remains a mystery, recent progress has begun to shed light upon the interplay of sex hormones, the pathogenesis of pulmonary hypertension, and the right ventricular response to stress. For example, emerging data in humans and experimental models suggest that estrogens or differential sex hormone metabolism may modify disease risk among susceptible subjects, and that estrogens may interact with additional local factors such as serotonin to enhance the potentially damaging chronic effects of estrogens on the pulmonary vasculature. Regardless, it remains unclear why not all estrogenic compounds behave equally, nor why estrogens appear to be protective in certain settings but detrimental in others. The contribution of androgens and other compounds, such as dehydroepiandrosterone, to pathogenesis and possibly treatment must be considered as well. In this review, we will discuss the recent understandings on how estrogens, estrogen metabolism, dehydroepiandrosterone, and additional susceptibility factors may all contribute to the pathogenesis or potentially to the treatment of pulmonary hypertension, by evaluating current human, cell-based, and experimental model data.

  1. Gender, sex hormones and pulmonary hypertension

    PubMed Central

    Austin, Eric D.; Lahm, Tim; West, James; Tofovic, Stevan P.; Johansen, Anne Katrine; MacLean, Margaret R.; Alzoubi, Abdallah; Oka, Masahiko

    2013-01-01

    Most subtypes of pulmonary arterial hypertension (PAH) are characterized by a greater susceptibility to disease among females, although females with PAH appear to live longer after diagnosis. While this “estrogen paradoxȍ of enhanced female survival despite increased female susceptibility remains a mystery, recent progress has begun to shed light upon the interplay of sex hormones, the pathogenesis of pulmonary hypertension, and the right ventricular response to stress. For example, emerging data in humans and experimental models suggest that estrogens or differential sex hormone metabolism may modify disease risk among susceptible subjects, and that estrogens may interact with additional local factors such as serotonin to enhance the potentially damaging chronic effects of estrogens on the pulmonary vasculature. Regardless, it remains unclear why not all estrogenic compounds behave equally, nor why estrogens appear to be protective in certain settings but detrimental in others. The contribution of androgens and other compounds, such as dehydroepiandrosterone, to pathogenesis and possibly treatment must be considered as well. In this review, we will discuss the recent understandings on how estrogens, estrogen metabolism, dehydroepiandrosterone, and additional susceptibility factors may all contribute to the pathogenesis or potentially to the treatment of pulmonary hypertension, by evaluating current human, cell-based, and experimental model data. PMID:24015330

  2. Additional Types of Neuropathy

    MedlinePlus

    ... A A Listen En Español Additional Types of Neuropathy Charcot's Joint Charcot's Joint, also called neuropathic arthropathy, ... can stop bone destruction and aid healing. Cranial Neuropathy Cranial neuropathy affects the 12 pairs of nerves ...

  3. Food Additives and Hyperkinesis

    ERIC Educational Resources Information Center

    Wender, Ester H.

    1977-01-01

    The hypothesis that food additives are causally associated with hyperkinesis and learning disabilities in children is reviewed, and available data are summarized. Available from: American Medical Association 535 North Dearborn Street Chicago, Illinois 60610. (JG)

  4. Smog control fuel additives

    SciTech Connect

    Lundby, W.

    1993-06-29

    A method is described of controlling, reducing or eliminating, ozone and related smog resulting from photochemical reactions between ozone and automotive or industrial gases comprising the addition of iodine or compounds of iodine to hydrocarbon-base fuels prior to or during combustion in an amount of about 1 part iodine per 240 to 10,000,000 parts fuel, by weight, to be accomplished by: (a) the addition of these inhibitors during or after the refining or manufacturing process of liquid fuels; (b) the production of these inhibitors for addition into fuel tanks, such as automotive or industrial tanks; or (c) the addition of these inhibitors into combustion chambers of equipment utilizing solid fuels for the purpose of reducing ozone.

  5. Family Experiences of Young Adult Sex Offender Registration

    ERIC Educational Resources Information Center

    Comartin, Erin B.; Kernsmith, Poco D.; Miles, Bart W.

    2010-01-01

    Since 1994, policies have been instituted throughout the United States that require sex offenders to register their personal information with law enforcement officials (Jacob Wetterling Crimes against Children and Sexually Violent Offender Registration Program, 1994). With the passage of additional laws, this information is now available to the…

  6. Sex Education for Deaf-Blind Youths and Adults.

    ERIC Educational Resources Information Center

    Ingraham, Cynthia L.; Vernon, McCay; Clemente, Brenda; Olney, Linda

    2000-01-01

    This article describes a model sex education program developed for youths and adults who are deafblind by the Helen Keller National Center for Deaf-Blind Youths and Adults. In addition, it also discusses major related issues and presents general recommendations and a resource for further information. (Contains 11 references.) (Author/CR)

  7. Inbreeding and parasite sex ratios.

    PubMed

    Nee, Sean; West, Stuart A; Read, Andrew F

    2002-04-01

    The breeding system of parasitic protozoa affects the evolution of drug resistance and virulence, and is relevant to disease diagnosis and the development of chemo- and immunotherapy. A major group of protozoan parasites, the phylum Apicomplexa, that includes the aetiological agents of malaria, toxoplasmosis and coccidiosis, all have dimorphic sexual stages. The sex ratio (proportion of males produced by parasites) is predicted to depend upon the inbreeding rate, and it has been suggested that sex-ratio data offer a relatively cheap and easy method for indirectly estimating inbreeding rates. Here, we exploit a new theoretical machinery to show that there are generally valid relationships between f, Wright's coefficient of inbreeding, and sex ratio, z(*), the generality being with respect to population structure. To focus the discussion, we concentrate on malaria and show that the previously derived result, f = 1 - 2z(*), does not depend on the artificial assumptions about population structure that were previously made. Not only does this justify the use of sex ratio as an indirect measure of f, but also we argue that it may actually be preferable to measure f by measuring sex ratios, rather than by measuring departures from Hardy-Weinberg genotypic proportions both in malaria and parasites more generally. PMID:11934369

  8. Sex work: a comparative study.

    PubMed

    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.

  9. Sex differences in cardiovascular ageing.

    PubMed

    Merz, Allison A; Cheng, Susan

    2016-06-01

    Despite recent progress in identifying and narrowing the gaps in cardiovascular outcomes between men and women, general understanding of how and why cardiovascular disease presentations differ between the sexes remains limited. Sex-specific patterns of cardiac and vascular ageing play an important role and, in fact, begin very early in life. Differences between the sexes in patterns of age-related cardiac remodelling are associated with the relatively greater prevalence in women than in men of heart failure with preserved ejection fraction. Similarly, sex variation in how vascular structure and function change with ageing contributes to differences between men and women in how coronary artery disease manifests typically or atypically over the adult life course. Both hormonal and non-hormonal factors underlie sex differences in cardiovascular ageing and the development of age-related disease. The midlife withdrawal of endogenous oestrogen appears to augment the age-related increase in cardiovascular risk seen in postmenopausal compared with premenopausal women. However, when compared with intrinsic biological differences between men and women that are present throughout life, this menopausal transition may not be as substantial an actor in determining cardiovascular outcomes. PMID:26917537

  10. Sex work: a comparative study.

    PubMed

    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. PMID:24671729

  11. [Pre-conception sex selection].

    PubMed

    Julesz, Máté

    2014-11-16

    According to Article 14 of the Oviedo Convention on Human Rights and Biomedicine of the Council of Europe, the use of techniques of medically assisted procreation shall not be allowed for the purpose of choosing the sex of a future child, unless serious hereditary sex-related disease is to be avoided. In Israel and the United States of America, pre-conception sex selection for the purpose of family balancing is legal. The European health culture does not regard reproductive justice as part of social justice. From this aspect, the situation is very similar in China and India. Reproductive liberty is opposed by the Catholic Church, too. According to the Catholic Church, medical grounds may not justify pre-conception sex selection, though being bioethically less harmful than family balancing for social reasons. In Hungary, according to Section 170 of the Criminal Code, pre-conception sex selection for the purpose of family balancing constitutes a crime. At present, the Hungarian legislation is in full harmony with the Oviedo Convention, enacted in Hungary in 2002.

  12. Autosomal gsdf acts as a male sex initiator in the fish medaka

    PubMed Central

    Zhang, Xi; Guan, Guijun; Li, Mingyou; Zhu, Feng; Liu, Qizhi; Naruse, Kiyoshi; Herpin, Amaury; Nagahama, Yoshitaka; Li, Jiale; Hong, Yunhan

    2016-01-01

    Sex is pivotal for reproduction, healthcare and evolution. In the fish medaka, the Y-chromosomal dmy (also dmrt1bY) serves the sex determiner, which activates dmrt1 for male sex maintenance. However, how dmy makes the male decision via initiating testicular differentiation has remained unknown. Here we report that autosomal gsdf serves a male sex initiator. Gene addition and deletion revealed that gsdf was necessary and sufficient for maleness via initiating testicular differentiation. We show that gsdf transcription is activated directly by dmy. These results establish the autosomal gsdf as the first male sex initiator. We propose that dmy determines maleness through activating gsdf and dmrt1 without its own participation in developmental processes of sex initiation and maintenance. gsdf may easily become a sex determiner or other autosomal genes can be recruited as new sex determiners to initiate gsdf expression. Our findings offer new insights into molecular mechanisms underlying sex development and evolution of sex-controlling genes in vertebrates. PMID:26813267

  13. Same-sex cohabitors and health: the role of race-ethnicity, gender, and socioeconomic status.

    PubMed

    Liu, Hui; Reczek, Corinne; Brown, Dustin

    2013-03-01

    A legacy of research finds that marriage is associated with good health. Yet same-sex cohabitors cannot marry in most states in the United States and therefore may not receive the health benefits associated with marriage. We use pooled data from the 1997 to 2009 National Health Interview Surveys to compare the self-rated health of same-sex cohabiting men (n = 1,659) and same-sex cohabiting women (n = 1,634) with that of their different-sex married, different-sex cohabiting, and unpartnered divorced, widowed, and never-married counterparts. Results from logistic regression models show that same-sex cohabitors report poorer health than their different-sex married counterparts at the same levels of socioeconomic status. Additionally, same-sex cohabitors report better health than their different-sex cohabiting and single counterparts, but these differences are fully explained by socioeconomic status. Without their socioeconomic advantages, same-sex cohabitors would report similar health to nonmarried groups. Analyses further reveal important racial-ethnic and gender variations.

  14. Different autosomes evolved into sex chromosomes in the sister genera of Salix and Populus.

    PubMed

    Hou, Jing; Ye, Ning; Zhang, Defang; Chen, Yingnan; Fang, Lecheng; Dai, Xiaogang; Yin, Tongming

    2015-03-13

    Willows (Salix) and poplars (Populus) are dioecious plants in Salicaceae family. Sex chromosome in poplar genome was consistently reported to be associated with chromosome XIX. In contrast to poplar, this study revealed that chromosome XV was sex chromosome in willow. Previous studies revealed that both ZZ/ZW and XX/XY sex-determining systems could be present in some species of Populus. In this study, sex of S. suchowensis was found to be determined by the ZW system in which the female was the heterogametic gender. Gene syntenic and collinear comparisons revealed macrosynteny between sex chromosomes and the corresponding autosomes between these two lineages. By contrast, no syntenic segments were found to be shared between poplar's and willow's sex chromosomes. Syntenic analysis also revealed substantial chromosome rearrangements between willow's alternate sex chromatids. Since willow and poplar originate from a common ancestor, we proposed that evolution of autosomes into sex chromosomes in these two lineages occurred after their divergence. Results of this study indicate that sex chromosomes in Salicaceae are still at the early stage of evolutionary divergence. Additionally, this study provided valuable information for better understanding the genetics and evolution of sex chromosome in dioecious plants.

  15. Different autosomes evolved into sex chromosomes in the sister genera of Salix and Populus

    PubMed Central

    Hou, Jing; Ye, Ning; Zhang, Defang; Chen, Yingnan; Fang, Lecheng; Dai, Xiaogang; Yin, Tongming

    2015-01-01

    Willows (Salix) and poplars (Populus) are dioecious plants in Salicaceae family. Sex chromosome in poplar genome was consistently reported to be associated with chromosome XIX. In contrast to poplar, this study revealed that chromosome XV was sex chromosome in willow. Previous studies revealed that both ZZ/ZW and XX/XY sex-determining systems could be present in some species of Populus. In this study, sex of S. suchowensis was found to be determined by the ZW system in which the female was the heterogametic gender. Gene syntenic and collinear comparisons revealed macrosynteny between sex chromosomes and the corresponding autosomes between these two lineages. By contrast, no syntenic segments were found to be shared between poplar's and willow's sex chromosomes. Syntenic analysis also revealed substantial chromosome rearrangements between willow's alternate sex chromatids. Since willow and poplar originate from a common ancestor, we proposed that evolution of autosomes into sex chromosomes in these two lineages occurred after their divergence. Results of this study indicate that sex chromosomes in Salicaceae are still at the early stage of evolutionary divergence. Additionally, this study provided valuable information for better understanding the genetics and evolution of sex chromosome in dioecious plants. PMID:25766834

  16. AIDS prevention in the sex industry.

    PubMed

    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

  17. AIDS prevention in the sex industry.

    PubMed

    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

  18. When can ants discriminate the sex of brood? A new aspect of queen-worker conflict.

    PubMed

    Nonacs, P; Carlin, N F

    1990-12-15

    The stage in preimaginal ontogeny at which the sexes can first be distinguished has important implications for queen-worker conflict in social insects. If workers are unable to sex larvae at an early instar, their opportunity to control colony reproductive strategies may be limited. In addition, by concealing the sex of her sons for some portion of development, the queen could protect them from the workers' attempts to substitute their own sons or to skew the numerical sex ratio. In a series of choice experiments, workers of the carpenter ant, Camponotus floridanus, failed to discriminate the sex of several stages of larvae but did retrieve female pupae significantly more rapidly than male pupae. Our results suggest that in this species, sex may not become detectable until pupation, which is consistent with sexual deception as an aspect of queen control.

  19. When can ants discriminate the sex of brood? A new aspect of queen-worker conflict.

    PubMed

    Nonacs, P; Carlin, N F

    1990-12-15

    The stage in preimaginal ontogeny at which the sexes can first be distinguished has important implications for queen-worker conflict in social insects. If workers are unable to sex larvae at an early instar, their opportunity to control colony reproductive strategies may be limited. In addition, by concealing the sex of her sons for some portion of development, the queen could protect them from the workers' attempts to substitute their own sons or to skew the numerical sex ratio. In a series of choice experiments, workers of the carpenter ant, Camponotus floridanus, failed to discriminate the sex of several stages of larvae but did retrieve female pupae significantly more rapidly than male pupae. Our results suggest that in this species, sex may not become detectable until pupation, which is consistent with sexual deception as an aspect of queen control. PMID:11607136

  20. Ecotoxicological Perspectives of Sex Determination.

    PubMed

    Mizoguchi, Beatriz A; Valenzuela, Nicole

    2016-01-01

    Sex determination or the commitment of the embryo to its sexual fate is a fundamental developmental process with paramount consequences in ecology and evolution. This process, whether triggered by environmental factors or genotypic constitution, can be derailed by environmental contaminants that alter the endocrine system, which is a key component of the regulatory network underlying vertebrate sex determination. Here, we review the molecular basis of sex determination, the endocrine components of its regulation, the maternal and endogenous sources of hormones to the developing embryo, and the routes through which endocrine disrupting chemicals (EDCs) affect gonadal development in reptiles, especially turtles. Among EDCs, we focus on PCBs, BPA, pesticides like atrazine, nitrates, and heavy metals. We also consider whether adaptation might be possible in the face of persistent chemical insult and conclude that, while plausible, contemporary environmental change may outpace adaptive evolution, particularly for many species that are already endangered and suffer from small population sizes. PMID:27022970

  1. Additive Manufacturing Infrared Inspection

    NASA Technical Reports Server (NTRS)

    Gaddy, Darrell

    2014-01-01

    Additive manufacturing is a rapid prototyping technology that allows parts to be built in a series of thin layers from plastic, ceramics, and metallics. Metallic additive manufacturing is an emerging form of rapid prototyping that allows complex structures to be built using various metallic powders. Significant time and cost savings have also been observed using the metallic additive manufacturing compared with traditional techniques. Development of the metallic additive manufacturing technology has advanced significantly over the last decade, although many of the techniques to inspect parts made from these processes have not advanced significantly or have limitations. Several external geometry inspection techniques exist such as Coordinate Measurement Machines (CMM), Laser Scanners, Structured Light Scanning Systems, or even traditional calipers and gages. All of the aforementioned techniques are limited to external geometry and contours or must use a contact probe to inspect limited internal dimensions. This presentation will document the development of a process for real-time dimensional inspection technique and digital quality record of the additive manufacturing process using Infrared camera imaging and processing techniques.

  2. Sex differences in adipose tissue

    PubMed Central

    Fuente-Martín, Esther; Argente-Arizón, Pilar; Ros, Purificación; Argente, Jesús; Chowen, Julie A

    2013-01-01

    Obesity and its associated secondary complications are active areas of investigation in search of effective treatments. As a result of this intensified research numerous differences between males and females at all levels of metabolic control have come to the forefront. These differences include not only the amount and distribution of adipose tissue, but also differences in its metabolic capacity and functions between the sexes. Here, we review some of the recent advances in our understanding of these dimorphisms and emphasize the fact that these differences between males and females must be taken into consideration in hopes of obtaining successful treatments for both sexes. PMID:23991358

  3. [Unclassified sex cord testis tumor].

    PubMed

    Grenha, Vânia; Serra, Paula; Coelho, Hugo; Retroz, Edson; Temido, Paulo; Mota, Alfredo

    2014-01-01

    Unclassified sex cord testis tumor is an extremely rare tumor, especially in the adult. It is characterized histologically for a nonspecific combination of testis stromal and epithelial elements, with varying degree of differentiation. Treatment usually consists of radical orchiectomy followed by clinical and imaging surveillance. The available literature about this pathology relies almost exclusively on clinical cases. It's our aim to describe the case of a 37 years old man with an unclassified sex cord testis tumor, the first case described in Portugal, and to review the literature about this issue.

  4. Monozygotic twins discordant for sex.

    PubMed Central

    Schmidt, R; Sobel, E H; Nitowsky, H M; Dar, H; Allen, F H

    1976-01-01

    A pair of monozygotic, adolescent twins is discordant for sex. The phenotypic female twin has chromosome constitution of 46, XY/45, X. She displays many signs of Turner's syndrome, including typical facies, webbed neck, malformed left kidney, high plasma gonadotropins, and streak ovaries. However, her height is 154 cm which exceeds the height usually reported in Turner's syndrome. The male twin has a karyotype of 46, XY and normal sexual development. Only two other reports of pairs of monozygotic twins of opposite sex have been published. Images PMID:944787

  5. Phenylethynyl Containing Reactive Additives

    NASA Technical Reports Server (NTRS)

    Connell, John W. (Inventor); Smith, Joseph G., Jr. (Inventor); Hergenrother, Paul M. (Inventor)

    2002-01-01

    Phenylethynyl containing reactive additives were prepared from aromatic diamine, containing phenylethvnvl groups and various ratios of phthalic anhydride and 4-phenylethynviphthalic anhydride in glacial acetic acid to form the imide in one step or in N-methyl-2-pvrrolidinone to form the amide acid intermediate. The reactive additives were mixed in various amounts (10% to 90%) with oligomers containing either terminal or pendent phenylethynyl groups (or both) to reduce the melt viscosity and thereby enhance processability. Upon thermal cure, the additives react and become chemically incorporated into the matrix and effect an increase in crosslink density relative to that of the host resin. This resultant increase in crosslink density has advantageous consequences on the cured resin properties such as higher glass transition temperature and higher modulus as compared to that of the host resin.

  6. Numerous transitions of sex chromosomes in Diptera.

    PubMed

    Vicoso, Beatriz; Bachtrog, Doris

    2015-04-01

    Many species groups, including mammals and many insects, determine sex using heteromorphic sex chromosomes. Diptera flies, which include the model Drosophila melanogaster, generally have XY sex chromosomes and a conserved karyotype consisting of six chromosomal arms (five large rods and a small dot), but superficially similar karyotypes may conceal the true extent of sex chromosome variation. Here, we use whole-genome analysis in 37 fly species belonging to 22 different families of Diptera and uncover tremendous hidden diversity in sex chromosome karyotypes among flies. We identify over a dozen different sex chromosome configurations, and the small dot chromosome is repeatedly used as the sex chromosome, which presumably reflects the ancestral karyotype of higher Diptera. However, we identify species with undifferentiated sex chromosomes, others in which a different chromosome replaced the dot as a sex chromosome or in which up to three chromosomal elements became incorporated into the sex chromosomes, and others yet with female heterogamety (ZW sex chromosomes). Transcriptome analysis shows that dosage compensation has evolved multiple times in flies, consistently through up-regulation of the single X in males. However, X chromosomes generally show a deficiency of genes with male-biased expression, possibly reflecting sex-specific selective pressures. These species thus provide a rich resource to study sex chromosome biology in a comparative manner and show that similar selective forces have shaped the unique evolution of sex chromosomes in diverse fly taxa.

  7. Numerous Transitions of Sex Chromosomes in Diptera

    PubMed Central

    Vicoso, Beatriz; Bachtrog, Doris

    2015-01-01

    Many species groups, including mammals and many insects, determine sex using heteromorphic sex chromosomes. Diptera flies, which include the model Drosophila melanogaster, generally have XY sex chromosomes and a conserved karyotype consisting of six chromosomal arms (five large rods and a small dot), but superficially similar karyotypes may conceal the true extent of sex chromosome variation. Here, we use whole-genome analysis in 37 fly species belonging to 22 different families of Diptera and uncover tremendous hidden diversity in sex chromosome karyotypes among flies. We identify over a dozen different sex chromosome configurations, and the small dot chromosome is repeatedly used as the sex chromosome, which presumably reflects the ancestral karyotype of higher Diptera. However, we identify species with undifferentiated sex chromosomes, others in which a different chromosome replaced the dot as a sex chromosome or in which up to three chromosomal elements became incorporated into the sex chromosomes, and others yet with female heterogamety (ZW sex chromosomes). Transcriptome analysis shows that dosage compensation has evolved multiple times in flies, consistently through up-regulation of the single X in males. However, X chromosomes generally show a deficiency of genes with male-biased expression, possibly reflecting sex-specific selective pressures. These species thus provide a rich resource to study sex chromosome biology in a comparative manner and show that similar selective forces have shaped the unique evolution of sex chromosomes in diverse fly taxa. PMID:25879221

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

    ERIC Educational Resources Information Center

    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…

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

    ERIC Educational Resources Information Center

    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…

  10. Considerations of Sex, Sex Role, and Competition Anxiety.

    ERIC Educational Resources Information Center

    Wittig, Arno F.

    Recent growth of sport psychology research has led to studies of the attitudes of women in sports. Using the Bem Sex Role Inventory and the Sport Competition Anxiety Test with 736 male and female subjects, one study found that: (1) Males with a masculine self description had the lowest levels of sports anxiety; (2) The "feminine" males had a very…

  11. Sex Differences in Stroke: The Contribution of Coagulation

    PubMed Central

    Roy-O’Reilly, Meaghan; McCullough, Louise D.

    2014-01-01

    Stroke is now the leading cause of adult disability in the United States. Women are disproportionately affected by stroke. Women increasingly outnumber men in the elderly population, the period of highest risk for stroke. However, there is also a growing recognition that fundamental sex differences are present that contribute to differential ischemic sensitivity. In addition, gonadal hormone exposure can impact coagulation and fibrinolysis, key factors in the initiation of thrombosis. In this review we will discuss sex differences in stroke, with a focus on platelets, vascular reactivity and coagulation. PMID:24560819

  12. Constrained sex allocation in a parasitoid due to variation in male quality.

    PubMed

    Henter, H J

    2004-07-01

    The theory of constrained sex allocation posits that when a fraction of females in a haplodiploid population go unmated and thus produce only male offspring, mated females will evolve to lay a female-biased sex ratio. I examined evidence for constrained sex ratio evolution in the parasitic hymenopteran Uscana semifumipennis. Mated females in the laboratory produced more female-biased sex ratios than the sex ratio of adults hatching from field-collected eggs, consistent with constrained sex allocation theory. However, the male with whom a female mated affected her offspring sex ratio, even when sperm was successfully transferred, suggesting that constrained sex ratios can occur even in populations where all females succeed in mating. A positive relationship between sex ratio and fecundity indicates that females may become sperm-limited. Variation among males occurred even at low fecundity, however, suggesting that other factors may also be involved. Further, a quantitative genetic experiment found significant additive genetic variance in the population for the sex ratio of offspring produced by females. This has only rarely been demonstrated in a natural population of parasitoids, but is a necessary condition for sex ratio evolution. Finally, matings with larger males produced more female-biased offspring sex-ratios, suggesting positive selection on male size. Because the great majority of parasitic hymenoptera are monandrous, the finding of natural variation among males in their capacity to fertilize offspring, even after mating successfully, suggests that females may often be constrained in the sex allocation by inadequate number or quality of sperm transferred.

  13. Male sex work and HIV risk among young heroin users in Hanoi, Vietnam.

    PubMed

    Clatts, Michael C; Giang, Le M; Goldsamt, Lloyd A; Yi, Huso

    2007-12-01

    The present study describes complex drug and sexual risk in a group of male sex workers (n = 79) who were recruited in the context of a larger study of young heroin users in Hanoi, Vietnam (n = 1270). Male sex workers were significantly more likely than male non-sex workers to be migrants (P < 0.001) and to have unstable housing (P < 0.001), to have lifetime exposure to marijuana (P < 0.001), 3,4 methylenedioxymethamphetamine (MDMA, ecstasy) (P < 0.01), amphetamines (P < 0.05), cocaine (P < 0.01) and morphine (P < 0.001). Male sex workers are more likely to currently use MDMA (P < 0.05), amphetamines (P < 0.001), morphine (P < 0.05) and to 'smoke' as their most frequent mode of heroin administration (P < 0.01). Male sex workers are more likely to have both male and female concurrent sex partners (P < 0.001), to have a history of sexual victimisation (P < 0.001), to have had more than three different sex partners in the past 30 days (P < 0.001), and to have had partners who injected drugs before sex (P < 0.001) or who used drugs during sex (P < 0.01). In their last sexual encounter with a client partner, approximately one-third (31.1%) reported having had receptive anal sex. In nearly three-quarters of these exchanges (71.4%), no condom was used. Similarly, in their last sexual encounter with a client partner, 42.2% reported having had insertive anal sex and in nearly half (47.4%) of these encounters no condom was used. Consistent with recent data from elsewhere in the region, there is an urgent need for additional research on male sex work in South-east Asia in order to properly situate behavioural interventions for male sex workers in this region.

  14. Maternal Condition but Not Corticosterone Is Linked to Offspring Sex Ratio in a Passerine Bird

    PubMed Central

    Henderson, Lindsay J.; Evans, Neil P.; Heidinger, Britt J.; Adams, Aileen; Arnold, Kathryn E.

    2014-01-01

    There is evidence of offspring sex ratio adjustment in a range of species, but the potential mechanisms remain largely unknown. Elevated maternal corticosterone (CORT) is associated with factors that can favour brood sex ratio adjustment, such as reduced maternal condition, food availability and partner attractiveness. Therefore, the steroid hormone has been suggested to play a key role in sex ratio manipulation. However, despite correlative and causal evidence CORT is linked to sex ratio manipulation in some avian species, the timing of adjustment varies between studies. Consequently, whether CORT is consistently involved in sex-ratio adjustment, and how the hormone acts as a mechanism for this adjustment remains unclear. Here we measured maternal baseline CORT and body condition in free-living blue tits (Cyanistes caeruleus) over three years and related these factors to brood sex ratio and nestling quality. In addition, a non-invasive technique was employed to experimentally elevate maternal CORT during egg laying, and its effects upon sex ratio and nestling quality were measured. We found that maternal CORT was not correlated with brood sex ratio, but mothers with elevated CORT fledged lighter offspring. Also, experimental elevation of maternal CORT did not influence brood sex ratio or nestling quality. In one year, mothers in superior body condition produced male biased broods, and maternal condition was positively correlated with both nestling mass and growth rate in all years. Unlike previous studies maternal condition was not correlated with maternal CORT. This study provides evidence that maternal condition is linked to brood sex ratio manipulation in blue tits. However, maternal baseline CORT may not be the mechanistic link between the maternal condition and sex ratio adjustment. Overall, this study serves to highlight the complexity of sex ratio adjustment in birds and the difficulties associated with identifying sex biasing mechanisms. PMID:25347532

  15. Multifunctional fuel additives

    SciTech Connect

    Baillargeon, D.J.; Cardis, A.B.; Heck, D.B.

    1991-03-26

    This paper discusses a composition comprising a major amount of a liquid hydrocarbyl fuel and a minor low-temperature flow properties improving amount of an additive product of the reaction of a suitable diol and product of a benzophenone tetracarboxylic dianhydride and a long-chain hydrocarbyl aminoalcohol.

  16. Biobased lubricant additives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fully biobased lubricants are those formulated using all biobased ingredients, i.e. biobased base oils and biobased additives. Such formulations provide the maximum environmental, safety, and economic benefits expected from a biobased product. Currently, there are a number of biobased base oils that...

  17. Uterine tumors resembling ovarian sex cord tumors: an update.

    PubMed

    Czernobilsky, Bernard

    2008-04-01

    express only 1 sex cord marker, mostly calretinin. However, additional studies are necessary to confirm these observations. In conclusion, UTROSCT and, to a lesser degree, ESTSCLE, are polyphenotypic neoplasms, which, according to the evidence available at present, most likely arise from pluripotential uterine mesenchymal cells. In UTROSCT, the differentiation into sex cord components is predominant or exclusive, whereas in ESTSCLE, it is minor.

  18. Application and commercialization of flow cytometrically sex-sorted semen.

    PubMed

    Rath, D; Johnson, L A

    2008-07-01

    The current technology to sort X and Y chromosome bearing sperm population requires individual identification and selection of spermatozoa in a modified high-speed flow cytometer. For farm animal species, the technology is capable of producing sexed sperm at greater than 90% purity. However, only in the bovine, the technology has reached a developmental level that allows its commercial application. Meanwhile, the demand for female calves has grown rapidly, which encourages the demand for sex-sorted semen from high genetic value bulls. The success of the technology will depend mainly on the fertilizing capacity of the sorted spermatozoa, as this is the most affecting and economically relevant factor. To date, fertility is still variable and is quite dependent on post-sort processing. New processing techniques are under investigation and will likely be able to improve the fertility rates after AI with sex-sorted semen. It is of great importance to select the right bulls and to test the sorted samples on a routine basis. In addition to the demand for sex-sorted semen by the cattle industry, there is also a significant demand expressed by pig farmers. However, it is still unknown if the use of sex-sorted semen through commercial pig AI will be economically feasible. For the pig, the combination of in vitro fertilization with sexed semen and non-surgical embryo transfer is an alternative that merits further scientific attention. Recent developments in ovine AI and ET will make it very likely that commercial sheep industry will adopt the sexing technology in their breeding concepts. PMID:18638144

  19. The Medical Response to Sex Trafficking of Minors in Wisconsin.

    PubMed

    Rabbitt, Angela

    2015-04-01

    Medical professionals are in a unique position to identify and assist pediatric victims of sex trafficking, who experience a high prevalence of physical, mental, and sexual health problems. However, providers report a need for education and guidelines for medical care of this population. A literature review was conducted on the nature and scope of pediatric sex trafficking in Wisconsin, the medical and mental health needs of victims, and existing guidelines for medical management. Few existing medical guidelines for the care of trafficking victims are specific to pediatrics or include specific recommendations for the forensic medical evaluation. Because of legislation and resources specific to Wisconsin, national guidelines may not apply locally. Based on the literature review, as well as input from community partners and medical professionals who frequently provide services to victims, guidelines for the medical care of pediatric sex trafficking victims in Wisconsin were developed. Additional community barriers that may prevent an effective medical response also are discussed. PMID:26756057

  20. Overexpression of Anti-Müllerian Hormone Disrupts Gonadal Sex Differentiation, Blocks Sex Hormone Synthesis, and Supports Cell Autonomous Sex Development in the Chicken.

    PubMed

    Lambeth, Luke S; Morris, Kirsten; Ayers, Katie L; Wise, Terry G; O'Neil, Terri; Wilson, Susanne; Cao, Yu; Sinclair, Andrew H; Cutting, Andrew D; Doran, Timothy J; Smith, Craig A

    2016-03-01

    The primary role of Anti-Müllerian hormone (AMH) during mammalian development is the regression of Müllerian ducts in males. This highly conserved function is retained in birds and is supported by the high levels of AMH expression in developing testes. Mammalian AMH expression is regulated by a combination of transcription factors, the most important being Sry-type high-mobility-group box transcription factor-9 (SOX9). In the chicken embryo, however, AMH mRNA expression precedes that of SOX9, leading to the view that AMH may play a more central role in avian testicular development. To define its role in chicken gonadal development, AMH was overexpressed using the RCASBP viral vector. AMH caused the gonads of both sexes to develop as small and undeveloped structures at both embryonic and adult stages. Molecular analysis revealed that although female gonads developed testis-like cords, gonads lacked Sertoli cells and were incapable of steroidogenesis. A similar gonadal phenotype was also observed in males, with a complete loss of both Sertoli cells, disrupted SOX9 expression and gonadal steroidogenesis. At sexual maturity both sexes showed a female external phenotype but retained sexually dimorphic body weights that matched their genetic sexes. These data suggest that AMH does not operate as an early testis activator in the chicken but can affect downstream events, such as sex steroid hormone production. In addition, this study provides a unique opportunity to assess chicken sexual development in an environment of sex hormone deficiency, demonstrating the importance of both hormonal signaling and direct cell autonomous factors for somatic sex identity in birds. PMID:26809122

  1. Group Process and Sex Differences.

    ERIC Educational Resources Information Center

    Kahn, Lynn Sandra

    1984-01-01

    Investigated theme development and role types in eight same-sex, self-analytic groups with male or female leadership, through the use of The General Inquirer, a computerized program of content analysis. All groups, male and female, showed a significant increase in the use of AFFILIATION words over time. (BH)

  2. Guess Who's Pregnant? Sex Education.

    ERIC Educational Resources Information Center

    Thoms, George H.; And Others

    Statistics on teenage pregnancy, the rate of venereal disease, and media representations of sexual mores are offered as rationale for the inclusion of sex education in the elementary-secondary school curriculum. The program of the George Mason Junior-Senior High School (Falls Church, Virginia) is described and used as a model for the discussion of…

  3. Sex Differences and Distributive Fairness.

    ERIC Educational Resources Information Center

    Russ, Terry Lee; Alexander, Sheldon

    In research on equity and justice some investigators have reported that men and women use different allocation norms in distributing rewards; men using an equity rule and women an equality rule, while others conclude that such sex differences in reward allocation appear primarily when the allocator is also a co-recipient of the reward. The present…

  4. Sex, Lies and Video Games

    ERIC Educational Resources Information Center

    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…

  5. Helping parents with sex education.

    PubMed

    Wakley, Gill

    2011-01-01

    Health visitors, school nurses and other community nurses are sometimes asked for advice by parents and carers on the emerging sexuality of their children. Parents often lack knowledge about sexual development and are confused about whether to talk to their children about sex. They may have been brought up in a family where sex was not mentioned. They are worried that they do not have the skills or the knowledge to help their children. They do not know whether to leave it all to the school or not allow their children to have any information. All the evidence shows that children who have had their questions answered and who know about sex and relationships start sexual activity later, use contraception more reliably and are less likely to cause or have an unwanted pregnancy. Sex education should be part of the ordinary information and moral guidance that parents normally give and should start as early as possible. The type of advice to give to parents and carers is split into age ranges that they might find helpful. Examples of language and the level of information required are given. A list of resources for further guidance is included.

  6. Sex Education. Grades K-12.

    ERIC Educational Resources Information Center

    Instructional Objectives Exchange, Los Angeles, CA.

    This collection of fifty objectives, related sample items, and directions for administering and scoring, is divided into three sections. The first, growth and development, deals with basic factual information relating to sex education; both animal and human biology are included. The second section, social and emotional growth, deals with the…

  7. Sex and the Public Schools.

    ERIC Educational Resources Information Center

    Black, Susan

    1995-01-01

    Recent statistics concerning teen pregnancies and sexually transmitted diseases are compelling reasons for reaching kids before they become sexually active. Comprehensive K-12 programs are essential, despite conflicts over abstinence, abstinence-but, and safer-sex approaches. Adverse program criticism can be diffused if administrators examine…

  8. Will sex selection reduce fertility?

    PubMed

    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%.

  9. Sex Differences in Problem Solving.

    ERIC Educational Resources Information Center

    Johnson, Edward S.

    1984-01-01

    Nine experiments were performed to verify and extend studies on sex differences in problem solving conducted in the 1950s by Sweeney, Carey, Milton, Nakamura, and Berry. A 20-item problem set was administered to over 1,000 college students. Results indicated a male advantage, averaging 35 percent, virtually identical with 1950s results. (Author/BS)

  10. Sex Stereotypes in Children's Literature.

    ERIC Educational Resources Information Center

    Craft, Julia

    The problem of sex stereotyping in children's literature has been around for as long as the genre itself, but it was brought to the forefront because of the women's movement in the 1970s. From the 1700s, critics were aware of the problems that arose from children's literature and its portrayal of characters and ideas, including "Cinderella" and…

  11. Creativity and Psychopathology: Sex Matters

    ERIC Educational Resources Information Center

    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…

  12. Sex Differences in Drug Disposition

    PubMed Central

    Soldin, Offie P.; Chung, Sarah H.; Mattison, Donald R.

    2011-01-01

    Physiological, hormonal, and genetic differences between males and females affect the prevalence, incidence, and severity of diseases and responses to therapy. Understanding these differences is important for designing safe and effective treatments. This paper summarizes sex differences that impact drug disposition and includes a general comparison of clinical pharmacology as it applies to men and women. PMID:21403873

  13. Personality, Sex, and Work Values.

    ERIC Educational Resources Information Center

    Hales, Loyde; Hartman, Timothy

    1978-01-01

    The Vocational Preference Inventory (VPA) and the Ohio Work Values Inventory (OWVI) were administered to 115 undergraduates. A two-factor MANOVA was performed with personality types (VPI) and sex as independent variables and work values (OWVI) as dependent variables. The F-ratios for main effects were significant. (Author/SJL)

  14. Sex Education in Multicultural Norway

    ERIC Educational Resources Information Center

    Bartz, Tiffany

    2007-01-01

    Scandinavia has long been admired by American liberals and sex education advocates who cite comparable rates of adolescent sexuality, yet lower rates of teenage pregnancy, sexually transmitted diseases and abortion in Scandinavia. The United States has, however, two variables with which Scandinavia in general, and Norway in particular, has not…

  15. Sex Differences in Spatial Abilities

    ERIC Educational Resources Information Center

    Eliot, John; Fralley, Jacqueline S.

    1976-01-01

    The fact that males outperform females on specific spatial tests is not generally disputed, but the explanations for these differences are controversial. This paper highlights unresolved issues, such as definitions of space and measurement of abilities, and illustrates problems of interpretation of research regarding sex differences. (Author/HS)

  16. Aspergillus: sex and recombination.

    PubMed

    Varga, János; Szigeti, Gyöngyi; Baranyi, Nikolett; Kocsubé, Sándor; O'Gorman, Céline M; Dyer, Paul S

    2014-12-01

    The genus Aspergillus is one of the most widespread groups of fungi on Earth, comprised of about 300-350 species with very diverse lifestyles. Most species produce asexual propagula (conidia) on conidial heads. Despite their ubiquity, a sexual cycle has not yet been identified for most of the aspergilli. Where sexual reproduction is present, species exhibit either homothallic (self fertile) or heterothallic (obligate outcrossing) breeding systems. A parasexual cycle has also been described in some Aspergillus species. As in other fungi, sexual reproduction is governed by mating-type (MAT) genes, which determine sexual identity and are involved in regulating later stages of sexual development. Previous population genetic studies have indicated that some supposedly asexual aspergilli exhibit evidence of a recombining population structure, suggesting the presence of a cryptic sexual cycle. In addition, genome analyses have revealed networks of genes necessary for sexual reproduction in several Aspergillus species, again consistent with latent sexuality in these fungi. Knowledge of MAT gene presence has then successfully been applied to induce sexual reproduction between MAT1-1 and MAT1-2 isolates of certain supposedly asexual aspergilli. Recent progress in understanding the extent and significance of sexual reproduction is described here, with special emphasis on findings that are relevant to clinically important aspergilli.

  17. Aspergillus: sex and recombination.

    PubMed

    Varga, János; Szigeti, Gyöngyi; Baranyi, Nikolett; Kocsubé, Sándor; O'Gorman, Céline M; Dyer, Paul S

    2014-12-01

    The genus Aspergillus is one of the most widespread groups of fungi on Earth, comprised of about 300-350 species with very diverse lifestyles. Most species produce asexual propagula (conidia) on conidial heads. Despite their ubiquity, a sexual cycle has not yet been identified for most of the aspergilli. Where sexual reproduction is present, species exhibit either homothallic (self fertile) or heterothallic (obligate outcrossing) breeding systems. A parasexual cycle has also been described in some Aspergillus species. As in other fungi, sexual reproduction is governed by mating-type (MAT) genes, which determine sexual identity and are involved in regulating later stages of sexual development. Previous population genetic studies have indicated that some supposedly asexual aspergilli exhibit evidence of a recombining population structure, suggesting the presence of a cryptic sexual cycle. In addition, genome analyses have revealed networks of genes necessary for sexual reproduction in several Aspergillus species, again consistent with latent sexuality in these fungi. Knowledge of MAT gene presence has then successfully been applied to induce sexual reproduction between MAT1-1 and MAT1-2 isolates of certain supposedly asexual aspergilli. Recent progress in understanding the extent and significance of sexual reproduction is described here, with special emphasis on findings that are relevant to clinically important aspergilli. PMID:25118872

  18. Role of sex and sex steroids in mediating pituitary-adrenal responses to acute buspirone treatment in sheep.

    PubMed

    Broadbear, J H; Pierce, B N; Clarke, I J; Canny, B J

    2005-12-01

    Systematic characterisation of sex differences in the serotonergic modulation of the hypothalamic-pituitary-adrenal (HPA) axis may assist with our understanding of why stress-related disorders are disproportionately represented in women. In this study, we examined the acute effects of buspirone, a serotonergic 1A receptor subtype agonist, on the endocrine endpoints of adrenocorticotrophin (ACTH) and cortisol secretion in gonadectomised male and female sheep. Each sheep was treated with an acute i.v. injection containing vehicle or buspirone (0.03, 0.1 and 0.3 mg/kg) in the presence and absence of sex steroid replacement (SSR). In males, SSR treatment consisted of testosterone (2 x 200 mg s.c. pellets) and, in females, the mid-luteal phase of the oestrus cycle was simulated by treatment with oestradiol (1 cm s.c. implant) and an intravaginal controlled internal drug release device containing 0.3 g progesterone. ACTH, cortisol, testosterone and progesterone were measured in jugular blood. Basal ACTH levels were higher in males, whereas basal cortisol levels were higher in females, regardless of sex steroid status. The magnitude of the increase in ACTH and cortisol secretion following buspirone treatment was dose-dependent. There were no differences in the ACTH responses of males and females to buspirone treatment, either in the presence or absence of sex steroid replacement. However, although the cortisol response to buspirone was greater in females, there was no discernable effect of sex steroid status in addition to this sex difference on either basal or buspirone-stimulated cortisol release. We conclude that the larger basal and buspirone-stimulated cortisol response measured in females may reflect a sex difference, either in the sensitivity of the adrenal gland to ACTH or in the catecholaminergic innervation of the adrenal gland. The lack of effect of sex and sex steroids in the ACTH secretory response to buspirone may indicate that the sex differences in

  19. Vinyl capped addition polyimides

    NASA Technical Reports Server (NTRS)

    Vannucci, Raymond D. (Inventor); Malarik, Diane C. (Inventor); Delvigs, Peter (Inventor)

    1991-01-01

    Polyimide resins (PMR) are generally useful where high strength and temperature capabilities are required (at temperatures up to about 700 F). Polyimide resins are particularly useful in applications such as jet engine compressor components, for example, blades, vanes, air seals, air splitters, and engine casing parts. Aromatic vinyl capped addition polyimides are obtained by reacting a diamine, an ester of tetracarboxylic acid, and an aromatic vinyl compound. Low void materials with improved oxidative stability when exposed to 700 F air may be fabricated as fiber reinforced high molecular weight capped polyimide composites. The aromatic vinyl capped polyimides are provided with a more aromatic nature and are more thermally stable than highly aliphatic, norbornenyl-type end-capped polyimides employed in PMR resins. The substitution of aromatic vinyl end-caps for norbornenyl end-caps in addition polyimides results in polymers with improved oxidative stability.

  20. Tackifier for addition polyimides

    NASA Technical Reports Server (NTRS)

    Butler, J. M.; St.clair, T. L.

    1980-01-01

    A modification to the addition polyimide, LaRC-160, was prepared to improve tack and drape and increase prepeg out-time. The essentially solventless, high viscosity laminating resin is synthesized from low cost liquid monomers. The modified version takes advantage of a reactive, liquid plasticizer which is used in place of solvent and helps solve a major problem of maintaining good prepeg tack and drape, or the ability of the prepeg to adhere to adjacent plies and conform to a desired shape during the lay up process. This alternate solventless approach allows both longer life of the polymer prepeg and the processing of low void laminates. This approach appears to be applicable to all addition polyimide systems.

  1. Effects of sex chromosome dosage on corpus callosum morphology in supernumerary sex chromosome aneuploidies

    PubMed Central

    2014-01-01

    Background Supernumerary sex chromosome aneuploidies (sSCA) are characterized by the presence of one or more additional sex chromosomes in an individual’s karyotype; they affect around 1 in 400 individuals. Although there is high variability, each sSCA subtype has a characteristic set of cognitive and physical phenotypes. Here, we investigated the differences in the morphometry of the human corpus callosum (CC) between sex-matched controls 46,XY (N =99), 46,XX (N =93), and six unique sSCA karyotypes: 47,XYY (N =29), 47,XXY (N =58), 48,XXYY (N =20), 47,XXX (N =30), 48,XXXY (N =5), and 49,XXXXY (N =6). Methods We investigated CC morphometry using local and global area, local curvature of the CC boundary, and between-landmark distance analysis (BLDA). We hypothesized that CC morphometry would vary differentially along a proposed spectrum of Y:X chromosome ratio with supernumerary Y karyotypes having the largest CC areas and supernumerary X karyotypes having significantly smaller CC areas. To investigate this, we defined an sSCA spectrum based on a descending Y:X karyotype ratio: 47,XYY, 46,XY, 48,XXYY, 47,XXY, 48,XXXY, 49,XXXXY, 46,XX, 47,XXX. We similarly explored the effects of both X and Y chromosome numbers within sex. Results of shape-based metrics were analyzed using permutation tests consisting of 5,000 iterations. Results Several subregional areas, local curvature, and BLDs differed between groups. Moderate associations were found between area and curvature in relation to the spectrum and X and Y chromosome counts. BLD was strongly associated with X chromosome count in both male and female groups. Conclusions Our results suggest that X- and Y-linked genes have differential effects on CC morphometry. To our knowledge, this is the first study to compare CC morphometry across these extremely rare groups. PMID:25780557

  2. Predicting the evolution of sex on complex fitness landscapes.

    PubMed

    Misevic, Dusan; Kouyos, Roger D; Bonhoeffer, Sebastian

    2009-09-01

    Most population genetic theories on the evolution of sex or recombination are based on fairly restrictive assumptions about the nature of the underlying fitness landscapes. Here we use computer simulations to study the evolution of sex on fitness landscapes with different degrees of complexity and epistasis. We evaluate predictors of the evolution of sex, which are derived from the conditions established in the population genetic literature for the evolution of sex on simpler fitness landscapes. These predictors are based on quantities such as the variance of Hamming distance, mean fitness, additive genetic variance, and epistasis. We show that for complex fitness landscapes all the predictors generally perform poorly. Interestingly, while the simplest predictor, Delta Var(HD), also suffers from a lack of accuracy, it turns out to be the most robust across different types of fitness landscapes. Delta Var(HD) is based on the change in Hamming distance variance induced by recombination and thus does not require individual fitness measurements. The presence of loci that are not under selection can, however, severely diminish predictor accuracy. Our study thus highlights the difficulty of establishing reliable criteria for the evolution of sex on complex fitness landscapes and illustrates the challenge for both theoretical and experimental research on the origin and maintenance of sexual reproduction.

  3. Erecting Sex: Hermaphrodites and the Medieval Science of Surgery.

    PubMed

    DeVun, Leah

    2015-01-01

    This essay focuses on "hermaphrodites" and the emerging profession of surgery in thirteenth- and fourteenth-century Europe. During this period, surgeons made novel claims about their authority to regulate sexual difference by surgically ''correcting" errant sexual anatomies. Their theories about sex, I argue, drew upon both ancient roots and contemporary conflicts to conceptualize sexual difference in ways that influenced Western Europe for centuries thereafter. I argue that a close examination of medieval surgical texts complicates orthodox narratives in the broader history of sex and sexuality: medieval theorists approached sex in sophisticated and varied manners that belie any simple opposition of modern and premodern paradigms. In addition, because surgical treatments of hermaphrodites in the Middle Ages prefigure in many ways the treatment of atypical sex (a condition now called, controversially, intersex or disorders/differences of sex development) in the modern world, I suggest that the writings of medieval surgeons have the potential to provide new perspectives on our current debates about surgery and sexual difference.

  4. Retroposon insertions and the chronology of avian sex chromosome evolution.

    PubMed

    Suh, Alexander; Kriegs, Jan Ole; Brosius, Jürgen; Schmitz, Jürgen

    2011-11-01

    The vast majority of extant birds possess highly differentiated Z and W sex chromosomes. Nucleotide sequence data from gametologs (homologs on opposite sex chromosomes) suggest that this divergence occurred throughout early bird evolution via stepwise cessation of recombination between identical sex chromosomal regions. Here, we investigated avian sex chromosome differentiation from a novel perspective, using retroposon insertions and random insertions/deletions for the reconstruction of gametologous gene trees. Our data confirm that the CHD1Z/CHD1W genes differentiated in the ancestor of the neognaths, whereas the NIPBLZ/NIPBLW genes diverged in the neoavian ancestor and independently within Galloanserae. The divergence of the ATP5A1Z/ATP5A1W genes in galloanserans occurred independently in the chicken, the screamer, and the ancestor of duck-related birds. In Neoaves, this gene pair differentiated in each of the six sampled representatives, respectively. Additionally, three of our investigated loci can be utilized as universal, easy-to-use independent tools for molecular sexing of Neoaves or Neognathae. PMID:21633113

  5. Erecting Sex: Hermaphrodites and the Medieval Science of Surgery.

    PubMed

    DeVun, Leah

    2015-01-01

    This essay focuses on "hermaphrodites" and the emerging profession of surgery in thirteenth- and fourteenth-century Europe. During this period, surgeons made novel claims about their authority to regulate sexual difference by surgically ''correcting" errant sexual anatomies. Their theories about sex, I argue, drew upon both ancient roots and contemporary conflicts to conceptualize sexual difference in ways that influenced Western Europe for centuries thereafter. I argue that a close examination of medieval surgical texts complicates orthodox narratives in the broader history of sex and sexuality: medieval theorists approached sex in sophisticated and varied manners that belie any simple opposition of modern and premodern paradigms. In addition, because surgical treatments of hermaphrodites in the Middle Ages prefigure in many ways the treatment of atypical sex (a condition now called, controversially, intersex or disorders/differences of sex development) in the modern world, I suggest that the writings of medieval surgeons have the potential to provide new perspectives on our current debates about surgery and sexual difference. PMID:27066617

  6. Is homophobia associated with an implicit same-sex attraction?

    PubMed

    Macinnis, Cara C; Hodson, Gordon

    2013-01-01

    Some theorists propose that homophobia stems from underlying same-sex attraction. A few studies have tested this hypothesis, yet without a clear measure of implicit sexual attraction, producing mixed results. For the first time, we test this attraction-based account of homophobia among both men and women using an implicit measure of sexual attraction. No evidence of an attraction-based account of homophobia emerged. Instead, implicit same-sex attraction was related to positive evaluations of gay men and lesbians among female participants. Even in targeted analyses examining the relation between implicit same-sex attraction and homosexual evaluations among only those theoretically most likely to demonstrate an attraction-based homophobic effect, implicit same-sex attraction was not associated with evaluations of homosexuals or was associated with more positive evaluations of homosexuals. In addition, explicit same-sex attraction was related to positive evaluations of gay men and lesbians for male participants. These results are more in keeping with the attitude-similarity effect (i.e., people like, rather than dislike, similar others).

  7. Electrophilic addition of astatine

    SciTech Connect

    Norseev, Yu.V.; Vasaros, L.; Nhan, D.D.; Huan, N.K.

    1988-03-01

    It has been shown for the first time that astatine is capable of undergoing addition reactions to unsaturated hydrocarbons. A new compound of astatine, viz., ethylene astatohydrin, has been obtained, and its retention numbers of squalane, Apiezon, and tricresyl phosphate have been found. The influence of various factors on the formation of ethylene astatohydrin has been studied. It has been concluded on the basis of the results obtained that the univalent cations of astatine in an acidic medium is protonated hypoastatous acid.

  8. Sex offenders and sex crime recidivism: investigating the role of sentence length and time served.

    PubMed

    Budd, Kristen; Desmond, Scott A

    2014-12-01

    The relationship between criminal justice sanctions and sex crime recidivism remains largely unexplored. Therefore, using a sample of 8,461 previously incarcerated male sex offenders from 13 states in the United States, we focus on the sentence meted out for the sex crime conviction and the amount of time sex offenders served as a result of their conviction. Sex offenders were grouped into four categories: rapists, sexual assaulters, child molesters, and all sex offenders combined. Recidivism was operationalized as rearrest and reconviction. Findings suggest how recidivism is operationalized matters. When recidivism is measured as rearrest for another sex offense, sentence length and time served are unrelated to sex crime recidivism. On the other hand, when recidivism is operationalized as reconviction for another sex offense, sentence length is positively related to recidivism for rapists, sexual assaulters, child molesters, and all sex offenders combined, while time served is negatively related to recidivism for child molesters and all sex offenders combined.

  9. Functional Generalized Additive Models.

    PubMed

    McLean, Mathew W; Hooker, Giles; Staicu, Ana-Maria; Scheipl, Fabian; Ruppert, David

    2014-01-01

    We introduce the functional generalized additive model (FGAM), a novel regression model for association studies between a scalar response and a functional predictor. We model the link-transformed mean response as the integral with respect to t of F{X(t), t} where F(·,·) is an unknown regression function and X(t) is a functional covariate. Rather than having an additive model in a finite number of principal components as in Müller and Yao (2008), our model incorporates the functional predictor directly and thus our model can be viewed as the natural functional extension of generalized additive models. We estimate F(·,·) using tensor-product B-splines with roughness penalties. A pointwise quantile transformation of the functional predictor is also considered to ensure each tensor-product B-spline has observed data on its support. The methods are evaluated using simulated data and their predictive performance is compared with other competing scalar-on-function regression alternatives. We illustrate the usefulness of our approach through an application to brain tractography, where X(t) is a signal from diffusion tensor imaging at position, t, along a tract in the brain. In one example, the response is disease-status (case or control) and in a second example, it is the score on a cognitive test. R code for performing the simulations and fitting the FGAM can be found in supplemental materials available online.

  10. HIV knowledge, risk perception, and safer sex practices among female sex workers in Port Moresby, Papua New Guinea

    PubMed Central

    Bruce, Eunice; Bauai, Ludwina; Sapuri, Mathias; Kaldor, John M; Fairley, Christopher K; Keogh, Louise A

    2011-01-01

    Sex workers are considered a high-risk group for sexually transmitted infections, including human immunodeficiency virus (HIV), and are often targeted by prevention interventions with safer sex messages. The purpose of this study was to explore the extent to which knowledge of HIV and perception of risk influence safer sex practices among female sex workers (FSWs) in Port Moresby, Papua New Guinea. FSWs (n = 174) were recruited from 19 sites to participate in the study. Qualitative data were collected using semistructured interviews with FSWs (n = 142) through focus group discussions and (n = 32) individual interviews. In addition, quantitative data were collected from all FSWs using a short structured, demographic questionnaire. Data were analyzed using recurring themes and calculations of confidence intervals. Despite some common misperceptions, overall, most FSWs were basically aware of the risks of HIV and informed about transmission and prevention modalities but used condoms inconsistently. Most reported using condoms ‘sometimes’, almost one-sixth ‘never’ used condoms, only a fraction used condoms ‘always’ with clients, and none used condoms ‘always’ with regular sexual partners (RSPs). Among these FSWs, being knowledgeable about the risks, transmission, and prevention of HIV did not translate into safe sex. The findings suggest that certain contextual barriers to safer sex practices exist. These barriers could heighten HIV vulnerability and possibly may be responsible for infection in FSWs. Specific interventions that focus on improving condom self-efficacy in FSWs and simultaneously target clients and RSPs with safer sex messages are recommended. PMID:21445375

  11. Sex reversal triggers the rapid transition from genetic to temperature-dependent sex.

    PubMed

    Holleley, Clare E; O'Meally, Denis; Sarre, Stephen D; Marshall Graves, Jennifer A; Ezaz, Tariq; Matsubara, Kazumi; Azad, Bhumika; Zhang, Xiuwen; Georges, Arthur

    2015-07-01

    Sex determination in animals is amazingly plastic. Vertebrates display contrasting strategies ranging from complete genetic control of sex (genotypic sex determination) to environmentally determined sex (for example, temperature-dependent sex determination). Phylogenetic analyses suggest frequent evolutionary transitions between genotypic and temperature-dependent sex determination in environmentally sensitive lineages, including reptiles. These transitions are thought to involve a genotypic system becoming sensitive to temperature, with sex determined by gene-environment interactions. Most mechanistic models of transitions invoke a role for sex reversal. Sex reversal has not yet been demonstrated in nature for any amniote, although it occurs in fish and rarely in amphibians. Here we make the first report of reptile sex reversal in the wild, in the Australian bearded dragon (Pogona vitticeps), and use sex-reversed animals to experimentally induce a rapid transition from genotypic to temperature-dependent sex determination. Controlled mating of normal males to sex-reversed females produces viable and fertile offspring whose phenotypic sex is determined solely by temperature (temperature-dependent sex determination). The W sex chromosome is eliminated from this lineage in the first generation. The instantaneous creation of a lineage of ZZ temperature-sensitive animals reveals a novel, climate-induced pathway for the rapid transition between genetic and temperature-dependent sex determination, and adds to concern about adaptation to rapid global climate change.

  12. How sex hormones promote skeletal muscle regeneration.

    PubMed

    Velders, Martina; Diel, Patrick

    2013-11-01

    Skeletal muscle regeneration efficiency declines with age for both men and women. This decline impacts on functional capabilities in the elderly and limits their ability to engage in regular physical activity and to maintain independence. Aging is associated with a decline in sex hormone production. Therefore, elucidating the effects of sex hormone substitution on skeletal muscle homeostasis and regeneration after injury or disuse is highly relevant for the aging population, where sarcopenia affects more than 30 % of individuals over 60 years of age. While the anabolic effects of androgens are well known, the effects of estrogens on skeletal muscle anabolism have only been uncovered in recent times. Hence, the purpose of this review is to provide a mechanistic insight into the regulation of skeletal muscle regenerative processes by both androgens and estrogens. Animal studies using estrogen receptor (ER) antagonists and receptor subtype selective agonists have revealed that estrogens act through both genomic and non-genomic pathways to reduce leukocyte invasion and increase satellite cell numbers in regenerating skeletal muscle tissue. Although animal studies have been more conclusive than human studies in establishing a role for sex hormones in the attenuation of muscle damage, data from a number of recent well controlled human studies is presented to support the notion that hormonal therapies and exercise induce added positive effects on functional measures and lean tissue mass. Based on the fact that aging human skeletal muscle retains the ability to adapt to exercise with enhanced satellite cell activation, combining sex hormone therapies with exercise may induce additive effects on satellite cell accretion. There is evidence to suggest that there is a 'window of opportunity' after the onset of a hypogonadal state such as menopause, to initiate a hormonal therapy in order to achieve maximal benefits for skeletal muscle health. Novel receptor subtype selective

  13. The Teacher and Sex Role Stereotyping

    ERIC Educational Resources Information Center

    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)

  14. Are secondary sex traits, parasites and immunity related to variation in primary sex traits in the Arctic charr?

    PubMed

    Måsvaer, Marthe; Liljedal, Ståle; Folstad, Ivar

    2004-02-01

    Primary and secondary sex traits are influenced by the same sex hormones, and the expression of secondary sex traits may consequently signal males' capacity for sperm production. Sperm quality may also be influenced by immune activity, as sperm are non-self to the male. Parasite infections alter immune activity and may thus reduce ejaculate quality. In the Arctic charr (Salvelinus alpinus) the red abdominal colour is considered an ornament that signals important information in mate choice. We captured and individually caged sexually mature male Arctic charr during the spawning period. Afterwards we estimated abdominal colour, parasite infections, gonad mass and several spermatological and immunological variables. Intensity of abdominal colour was positively correlated to testes mass, milt mass and sperm cell numbers produced. Additionally, males with low parasite intensities had high testes mass and produced milt with high sperm density, indicating a trade-off between parasite resistance and development of primary sex traits. Our measures of immunity were, however, not related to primary sex traits. We conclude that females evaluating male abdominal coloration may obtain information about differences between males in fertilization potential and parasite resistance.

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

    ERIC Educational Resources Information Center

    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…

  16. Sex work, reform initiatives and HIV/AIDS in inner-city Johannesburg.

    PubMed

    Richter, Marlise

    2008-11-01

    The on-going criminalisation of sex work in South Africa, concurrent sexual partnerships, socio-economic vulnerability, migrant status and gender-based violence intensify sex workers' risk of contracting HIV. These factors combine to restrict the skills, ability and resources of sex workers to negotiate safer sex and to access HIV prevention, treatment and healthcare services. The paper situates the living and working conditions of sex workers in Hillbrow, an inner-city area of Johannesburg, within the South African legal context, especially in regard to current law reform initiatives regarding sex work, as well as the increasing anxiety about the influx of (sex) tourists during the 2010 FIFA World Cup. In addition, the paper describes an intervention by the Reproductive Health & HIV Research Unit at the University of the Witwatersrand, Johannesburg, an innovator in providing mobile healthcare services and education to hotel-based sex workers in Hillbrow. The paper contends that a legal-rights-approach to HIV risk and vulnerability, together with powerful public health considerations, render decriminalisation an imperative response to sex workers' material conditions. PMID:25875460

  17. Deciphering evolutionary strata on plant sex chromosomes and fungal mating-type chromosomes through compositional segmentation.

    PubMed

    Pandey, Ravi S; Azad, Rajeev K

    2016-03-01

    Sex chromosomes have evolved from a pair of homologous autosomes which differentiated into sex determination systems, such as XY or ZW system, as a consequence of successive recombination suppression between the gametologous chromosomes. Identifying the regions of recombination suppression, namely, the "evolutionary strata", is central to understanding the history and dynamics of sex chromosome evolution. Evolution of sex chromosomes as a consequence of serial recombination suppressions is well-studied for mammals and birds, but not for plants, although 48 dioecious plants have already been reported. Only two plants Silene latifolia and papaya have been studied until now for the presence of evolutionary strata on their X chromosomes, made possible by the sequencing of sex-linked genes on both the X and Y chromosomes, which is a requirement of all current methods that determine stratum structure based on the comparison of gametologous sex chromosomes. To circumvent this limitation and detect strata even if only the sequence of sex chromosome in the homogametic sex (i.e. X or Z chromosome) is available, we have developed an integrated segmentation and clustering method. In application to gene sequences on the papaya X chromosome and protein-coding sequences on the S. latifolia X chromosome, our method could decipher all known evolutionary strata, as reported by previous studies. Our method, after validating on known strata on the papaya and S. latifolia X chromosome, was applied to the chromosome 19 of Populus trichocarpa, an incipient sex chromosome, deciphering two, yet unknown, evolutionary strata. In addition, we applied this approach to the recently sequenced sex chromosome V of the brown alga Ectocarpus sp. that has a haploid sex determination system (UV system) recovering the sex determining and pseudoautosomal regions, and then to the mating-type chromosomes of an anther-smut fungus Microbotryum lychnidis-dioicae predicting five strata in the non

  18. Deciphering evolutionary strata on plant sex chromosomes and fungal mating-type chromosomes through compositional segmentation.

    PubMed

    Pandey, Ravi S; Azad, Rajeev K

    2016-03-01

    Sex chromosomes have evolved from a pair of homologous autosomes which differentiated into sex determination systems, such as XY or ZW system, as a consequence of successive recombination suppression between the gametologous chromosomes. Identifying the regions of recombination suppression, namely, the "evolutionary strata", is central to understanding the history and dynamics of sex chromosome evolution. Evolution of sex chromosomes as a consequence of serial recombination suppressions is well-studied for mammals and birds, but not for plants, although 48 dioecious plants have already been reported. Only two plants Silene latifolia and papaya have been studied until now for the presence of evolutionary strata on their X chromosomes, made possible by the sequencing of sex-linked genes on both the X and Y chromosomes, which is a requirement of all current methods that determine stratum structure based on the comparison of gametologous sex chromosomes. To circumvent this limitation and detect strata even if only the sequence of sex chromosome in the homogametic sex (i.e. X or Z chromosome) is available, we have developed an integrated segmentation and clustering method. In application to gene sequences on the papaya X chromosome and protein-coding sequences on the S. latifolia X chromosome, our method could decipher all known evolutionary strata, as reported by previous studies. Our method, after validating on known strata on the papaya and S. latifolia X chromosome, was applied to the chromosome 19 of Populus trichocarpa, an incipient sex chromosome, deciphering two, yet unknown, evolutionary strata. In addition, we applied this approach to the recently sequenced sex chromosome V of the brown alga Ectocarpus sp. that has a haploid sex determination system (UV system) recovering the sex determining and pseudoautosomal regions, and then to the mating-type chromosomes of an anther-smut fungus Microbotryum lychnidis-dioicae predicting five strata in the non

  19. Analyzing Medical Students' Definitions of Sex

    ERIC Educational Resources Information Center

    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.…

  20. 77 FR 73558 - Sex Offender Registration Amendments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-11

    ... SUPERVISION AGENCY FOR THE DISTRICT OF COLUMBIA 28 CFR Part 811 RIN 3225-AA10 Sex Offender Registration... requirements relating to periodic verification of registration information for sex offenders. The proposed rule, if finalized, would permit CSOSA to verify addresses of sex offenders by conducting home visits...

  1. The Promise of Single-Sex Classes

    ERIC Educational Resources Information Center

    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 ineffective…

  2. Sex-Roles: Why, What, and How.

    ERIC Educational Resources Information Center

    Schwartz, Lita Linzer

    The teaching of sex-role stereotyping issues in an educational psychology course for student teachers is discussed. Issues presented include influences on the learner, the teaching of sex roles and stereotypes in the elementary grades, the presence of role models at home and school, contributions of curriculum to sex-role stereotyping and the…

  3. [Sex inversion and epigenetic regulation in Vertebrates].

    PubMed

    Trukhina, A V; Lukina, N A; Nekrasova, A A; Smirnov, A F

    2015-03-01

    This review discusses issues related to the regulation of sex determination and differentiation in various groups of Vertebrates. Special attention was paid to factors of external and internal control for various genetic systems of sex determination, as well as to the epigenetic control of this process. Opportunities for sex inversion in various animals were also discussed.

  4. Sex Education: More Is Not Enough.

    ERIC Educational Resources Information Center

    Mellanby, Alex; And Others

    1992-01-01

    There recently have been increasing demands for sex education. Peer led teaching is a powerful and probably essential component of school health and sex education programs. Evaluated interventions with agreed purpose and acceptable methodologies are essential if there is to be any real expectation of health benefit from sex education. (Author/NB)

  5. YA Sex Guiding: A Library Imperative.

    ERIC Educational Resources Information Center

    Campbell, Patty

    1986-01-01

    Presents excerpt from introductory chapters of author's forthcoming comprehensive sourcebook on young adult sexuality materials, "Sex Guides: Books and Films about Sexuality for Young Adults." History of sex education, social trends contributing to ambivalence in sexual attitudes, patterns of adolescent sexual activity, and sex education manuals…

  6. Answering Young Children's Questions about Sex.

    ERIC Educational Resources Information Center

    Hansen, Gladys

    Intended for use by parents and teachers of preschool age children, this short booklet provides some guidelines to follow when introducing sex education to young children. It discusses issues such as where to begin, how to encourage the child to ask questions about sex, how to handle sex-related problems, child molestation, nudity and the family,…

  7. Talking to Your Parents about Sex

    MedlinePlus

    ... to have sex makes sense Talking to your parents about sex Deciding about sex Birth control Types of birth control Could I get pregnant ... can be tough being a teen, and your parents and caregivers can be a great source ... or help getting birth control? Knowing what you want can make it easier ...

  8. ``Sex Hormones'' in Secondary School Biology Textbooks

    NASA Astrophysics Data System (ADS)

    Nehm, Ross H.; Young, Rebecca

    2008-11-01

    This study explores the extent to which the term “sex hormone” is used in science textbooks, and whether the use of the term “sex hormone” is associated with pre-empirical concepts of sex dualism, in particular the misconceptions that these so-called “sex hormones” are sex specific and restricted to sex-related physiological functioning. We found that: (1) all the texts employed the term “sex hormone”; (2) in all texts estrogen is characterized as restricted to females and testosterone is characterized as restricted to males; and (3) in all texts testosterone and estrogen are discussed as exclusively involved in sex-related physiological roles. We conclude that (1) contemporary science textbooks preserve sex-dualistic models of steroid hormones (one sex, one “sex hormone”) that were rejected by medical science in the early 20th century and (2) use of the term “sex hormone” is associated with misconceptions regarding the presence and functions of steroid hormones in male and female bodies.

  9. Sex and the Education of Our Children.

    ERIC Educational Resources Information Center

    Bennett, William J.

    Schools, teachers, and principals must help develop good character by putting children in the presence of adults of good character who live the difference between right and wrong. Sex education is about character; in a sex education course issues of right and wrong should occupy center stage. In too may cases, however, sex education in American…

  10. Genomic architecture of asthma differs by sex.

    PubMed

    Mersha, Tesfaye B; Martin, Lisa J; Biagini Myers, Jocelyn M; Kovacic, Melinda Butsch; He, Hua; Lindsey, Mark; Sivaprasad, Umasundari; Chen, Weiguo; Khurana Hershey, Gurjit K

    2015-07-01

    Asthma comprised of highly heterogeneous subphenotypes resulting from complex interplay between genetic and environmental stimuli. While much focus has been placed on extrinsic environmental stimuli, intrinsic environment such as sex can interact with genes to influence asthma risk. However, few studies have examined sex-specific genetic effects. The overall objective of this study was to evaluate if sex-based differences exist in genomic associations with asthma. We tested 411 asthmatics and 297 controls for presence of interactions and sex-stratified effects in 51 genes using both SNP and gene expression data. Logistic regression was used to test for association. Over half (55%) of the genetic variants identified in sex-specific analyses were not identified in the sex-combined analysis. Further, sex-stratified genetic analyses identified associations with significantly higher median effect sizes than sex-combined analysis for girls (p-value=6.5E-15) and for boys (p-value=1.0E-7). When gene expression data were analyzed to identify genes that were differentially expressed in asthma versus non-asthma, nearly one third (31%) of the probes identified in the sex-specific analyses were not identified in the sex-combined analysis. Both genetic and gene expression data suggest that the biologic underpinnings for asthma may differ by sex. Failure to recognize sex interactions in asthma greatly decreases the ability to detect significant genomic variation and may result in significant misrepresentation of genes and pathways important in asthma in different environments.

  11. Guidelines on Discrimination Because of Sex.

    ERIC Educational Resources Information Center

    Equal Employment Opportunity Commission, Washington, DC.

    This brochure presents regulatory guidelines on sex discrimination with sections devoted to: general principles; sex as a bona fide occupational qualification; separate lines of progression and seniority systems; discrimination against married women; advertising job opportunities; employment agencies; pre-employment inquiries as to sex; the…

  12. The Advantages of Single-Sex Education

    ERIC Educational Resources Information Center

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

    ERIC Educational Resources Information Center

    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…

  14. A neo-sex-chromosome that drives post-zygotic sex determiniation in the Hessian fly

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two nonoverlapping autosomal inversions defined unusual neo-sex chromosomes in the Hessian fly (Mayetiola destructor). Like other neo-sex chromosomes, these were normally heterozygous, present only in one sex, and suppressed recombination around a sex-determining master switch. Their unusual propert...

  15. Single-sex middle school science classrooms: Separate and equal?

    NASA Astrophysics Data System (ADS)

    Glasser, Howard M.

    The U.S. Department of Education's amended regulations to Title IX have attempted to expand the circumstances in which single-sex classes are permissible in public schools. This ethnographic study uses grounded theory to investigate aspects of one single-sex offering at a public, coeducational middle school. Applying elements of postmodern, queer, and sociocultural lenses, it examines the perspectives for this offering, shedding insight into the cultures of two single-sex classrooms and what it meant to be a boy or girl in this setting. Additionally, it focuses attention on the all-boy and all-girl science classes that were taught by the same teacher and examines what it meant to learn science as boys and girls in this program. Although participants supplied financial, socio-emotional, and academic reasons for these classes, the initial motivation for these classes stemmed from the teachers' desire to curb the amount of sex talk and related behaviors that were exhibited in their classrooms. Through these conversations and classroom events, the girls were constructed as idealized students, academically and behaviorally, who needed to be protected from boys' behaviors---both boys' dominating classroom behaviors and aggressive (hetero)sexual behaviors. Conversely, boys were constructed as needing help both academically and behaviorally, but in the specific discipline of science boys were identified as the sex that was more interested in the content and gained greater exposure to skills that could assist them in future science courses and careers. Overall, boys and girls, and the culture of their two classrooms, were regularly defined relative to each other and efforts were made to maintain these constructed differences. As a result, the classes and students were hierarchically ranked in ways that often pitted one sex of students, or the entire class, as better or worse than the other. The theory emerging from this study is that single-sex policies arise and survive

  16. Discounting of food, sex, and money.

    PubMed

    Holt, Daniel D; Newquist, Matthew H; Smits, Rochelle R; Tiry, Andrew M

    2014-06-01

    Discounting is a useful framework for understanding choice involving a range of delayed and probabilistic outcomes (e.g., money, food, drugs), but relatively few studies have examined how people discount other commodities (e.g., entertainment, sex). Using a novel discounting task, where the length of a line represented the value of an outcome and was adjusted using a staircase procedure, we replicated previous findings showing that individuals discount delayed and probabilistic outcomes in a manner well described by a hyperbola-like function. In addition, we found strong positive correlations between discounting rates of delayed, but not probabilistic, outcomes. This suggests that discounting of delayed outcomes may be relatively predictable across outcome types but that discounting of probabilistic outcomes may depend more on specific contexts. The generality of delay discounting and potential context dependence of probability discounting may provide important information regarding factors contributing to choice behavior.

  17. Effects of Steroid Hormones on Sex Differences in Cerebral Perfusion.

    PubMed

    Ghisleni, Carmen; Bollmann, Steffen; Biason-Lauber, Anna; Poil, Simon-Shlomo; Brandeis, Daniel; Martin, Ernst; Michels, Lars; Hersberger, Martin; Suckling, John; Klaver, Peter; O'Gorman, Ruth L

    2015-01-01

    Sex differences in the brain appear to play an important role in the prevalence and progression of various neuropsychiatric disorders, but to date little is known about the cerebral mechanisms underlying these differences. One widely reported finding is that women demonstrate higher cerebral perfusion than men, but the underlying cause of this difference in perfusion is not known. This study investigated the putative role of steroid hormones such as oestradiol, testosterone, and dehydroepiandrosterone sulphate (DHEAS) as underlying factors influencing cerebral perfusion. We acquired arterial spin labelling perfusion images of 36 healthy adult subjects (16 men, 20 women). Analyses on average whole brain perfusion levels included a multiple regression analysis to test for the relative impact of each hormone on the global perfusion. Additionally, voxel-based analyses were performed to investigate the sex difference in regional perfusion as well as the correlations between local perfusion and serum oestradiol, testosterone, and DHEAS concentrations. Our results replicated the known sex difference in perfusion, with women showing significantly higher global and regional perfusion. For the global perfusion, DHEAS was the only significant predictor amongst the steroid hormones, showing a strong negative correlation with cerebral perfusion. The voxel-based analyses revealed modest sex-dependent correlations between local perfusion and testosterone, in addition to a strong modulatory effect of DHEAS in cortical, subcortical, and cerebellar regions. We conclude that DHEAS in particular may play an important role as an underlying factor driving the difference in cerebral perfusion between men and women.

  18. Performance Boosting Additive

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Mainstream Engineering Corporation was awarded Phase I and Phase II contracts from Goddard Space Flight Center's Small Business Innovation Research (SBIR) program in early 1990. With support from the SBIR program, Mainstream Engineering Corporation has developed a unique low cost additive, QwikBoost (TM), that increases the performance of air conditioners, heat pumps, refrigerators, and freezers. Because of the energy and environmental benefits of QwikBoost, Mainstream received the Tibbetts Award at a White House Ceremony on October 16, 1997. QwikBoost was introduced at the 1998 International Air Conditioning, Heating, and Refrigeration Exposition. QwikBoost is packaged in a handy 3-ounce can (pressurized with R-134a) and will be available for automotive air conditioning systems in summer 1998.

  19. Sewage sludge additive

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Mueller, W. A.; Ingham, J. D. (Inventor)

    1980-01-01

    The additive is for a raw sewage treatment process of the type where settling tanks are used for the purpose of permitting the suspended matter in the raw sewage to be settled as well as to permit adsorption of the dissolved contaminants in the water of the sewage. The sludge, which settles down to the bottom of the settling tank is extracted, pyrolyzed and activated to form activated carbon and ash which is mixed with the sewage prior to its introduction into the settling tank. The sludge does not provide all of the activated carbon and ash required for adequate treatment of the raw sewage. It is necessary to add carbon to the process and instead of expensive commercial carbon, coal is used to provide the carbon supplement.

  20. Perspectives on Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Bourell, David L.

    2016-07-01

    Additive manufacturing (AM) has skyrocketed in visibility commercially and in the public sector. This article describes the development of this field from early layered manufacturing approaches of photosculpture, topography, and material deposition. Certain precursors to modern AM processes are also briefly described. The growth of the field over the last 30 years is presented. Included is the standard delineation of AM technologies into seven broad categories. The economics of AM part generation is considered, and the impacts of the economics on application sectors are described. On the basis of current trends, the future outlook will include a convergence of AM fabricators, mass-produced AM fabricators, enabling of topology optimization designs, and specialization in the AM legal arena. Long-term developments with huge impact are organ printing and volume-based printing.

  1. Sarks as additional fermions

    NASA Astrophysics Data System (ADS)

    Agrawal, Jyoti; Frampton, Paul H.; Jack Ng, Y.; Nishino, Hitoshi; Yasuda, Osamu

    1991-03-01

    An extension of the standard model is proposed. The gauge group is SU(2) X ⊗ SU(3) C ⊗ SU(2) S ⊗ U(1) Q, where all gauge symmetries are unbroken. The colour and electric charge are combined with SU(2) S which becomes strongly coupled at approximately 500 GeV and binds preons to form fermionic and vector bound states. The usual quarks and leptons are singlets under SU(2) X but additional fermions, called sarks. transform under it and the electroweak group. The present model explains why no more than three light quark-lepton families can exist. Neutral sark baryons, called narks, are candidates for the cosmological dark matter having the characteristics designed for WIMPS. Further phenomenological implications of sarks are analyzed i including electron-positron annihilation. Z 0 decay, flavor-changing neutral currents. baryon-number non-conservation, sarkonium and the neutron electric dipole moment.

  2. Molecular players involved in temperature-dependent sex determination and sex differentiation in Teleost fish

    PubMed Central

    2014-01-01

    The molecular mechanisms that underlie sex determination and differentiation are conserved and diversified. In fish species, temperature-dependent sex determination and differentiation seem to be ubiquitous and molecular players involved in these mechanisms may be conserved. Although how the ambient temperature transduces signals to the undifferentiated gonads remains to be elucidated, the genes downstream in the sex differentiation pathway are shared between sex-determining mechanisms. In this paper, we review recent advances on the molecular players that participate in the sex determination and differentiation in fish species, by putting emphasis on temperature-dependent sex determination and differentiation, which include temperature-dependent sex determination and genetic sex determination plus temperature effects. Application of temperature-dependent sex differentiation in farmed fish and the consequences of temperature-induced sex reversal are discussed. PMID:24735220

  3. Sex differences in addictive disorders.

    PubMed

    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.

  4. Sex differences in addictive disorders.

    PubMed

    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. PMID:24769267

  5. Allergic contact dermatitis: Sex differences.

    PubMed

    Leyden, J J; Kligman, A M

    1977-12-01

    Using the repeated insult test, Jordan & King (1977) observed that contact sensitization was more readily induced in females than in males. We reviewed data obtained by maximization testing of 185 test substances of which 73 were allergenic. The overall male-female sensitization rates were respectively 9.9 and 9.2%. Only with the weakest allergens (sensitizing one or two subjects of a 25-member panel) was there a possibility of female predominance in that there were twice as many panels having only female reactors as males exclusively. In these instances, the test agents were mainly fragrances. We have concluded that sex differences, in the prevalence of sensitization to particular substances, reflect past exposure and are not due to sex differences.

  6. Sex differences in intimate relationships

    PubMed Central

    Palchykov, Vasyl; Kaski, Kimmo; Kertész, Janos; Barabási, Albert-László; Dunbar, Robin I. M.

    2012-01-01

    Social networks based on dyadic relationships are fundamentally important for understanding of human sociality. However, we have little understanding of the dynamics of close relationships and how these change over time. Evolutionary theory suggests that, even in monogamous mating systems, the pattern of investment in close relationships should vary across the lifespan when post-weaning investment plays an important role in maximising fitness. Mobile phone data sets provide a unique window into the structure and dynamics of relationships. We here use data from a large mobile phone dataset to demonstrate striking sex differences in the gender-bias of preferred relationships that reflect the way the reproductive investment strategies of both sexes change across the lifespan, i.e. women's shifting patterns of investment in reproduction and parental care. These results suggest that human social strategies may have more complex dynamics than previously assumed and a life-history perspective is crucial for understanding them. PMID:22518274

  7. [Globalization and the second sex].

    PubMed

    da Fonseca, Adriana Dora; Madureira, Valéria Silvana Faganello

    2003-01-01

    This paper is a reflection which takes as a starting point the process of globalization, establishing a counterpoint between the characteristics of this process and the propositions of the International Conference on Population and Development/1994, aiming at discussing it according to Sen's (2000, 2001) writings. This comparative analysis indicates that the discussion about equality between the sexes has become more globalized, emphasizing women's situation in the contemporary world as an obstacle to development, which was reaffirmed in the IV Women's World Convention in 1995. Subsequently, the paper addresses the advances occurred in Brazil after the implementations of the propositions of the Conference. Finally, it concludes by locating the search of equality between sexes in the fields of rights and opportunities as a social necessity strictly connected to development.

  8. Mutilation, deception, and sex changes.

    PubMed Central

    Lavin, M

    1987-01-01

    The paper considers and rejects two arguments against the performance of sexual reassignment surgery. First, it is argued that the operation is not mutilating, but functionally enabling. Second, it is argued that the operation is not objectionably deceptive, since, if there is such a thing as our 'real sex', we do not know (ordinarily) what it is. The paper is also intended to shed light on what our sexual identity is and on what matters in sexual relations. PMID:3612700

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

    PubMed Central

    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

  10. [Does really sex addiction exist?].

    PubMed

    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. PMID:23241714

  11. [Does really sex addiction exist?].

    PubMed

    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.

  12. Sex trafficking in South Asia.

    PubMed

    Huda, S

    2006-09-01

    Economic and social inequalities and political conflicts have led to the movement of persons within each country and across the borders in South Asia. Globalization has encouraged free mobility of capital, technology, experts and sex tourism. Illiteracy, dependency, violence, social stigma, cultural stereotypes, gender disparity and endemic poverty, among other factors, place women and children in powerless, non-negotiable situations that have contributed to the emergence and breeding of the cavernous problem of sex trafficking in the entire region. This alarming spread of sex trafficking has fuelled the spread of HIV infection in South Asia, posing a unique and serious threat to community health, poverty alleviation and other crucial aspects of human development. Although the SAARC (South Asian Association for Regional Cooperation) Convention on Trafficking in Women and Children has been an important breakthrough, most of the countries in the region do not have anti-trafficking legislation or means to protect the victims. Countries of the region should make a concerted effort to treat trafficking victims as "victims" of human rights violations in all anti-trafficking strategies and actions.

  13. Condom ads promote illicit sex.

    PubMed

    Kippley, J F

    1994-01-01

    Written in 1987, this opinion was republished in the wake of US President Bill Clinton's AIDS prevention media campaign promoting condom use which began January 1994, targeted at young adults aged 18-25. The author staunchly opposes condom use even though he admits that people do not consider abstinence from sex to be a serious option for the prevention of HIV/STD infection. He believes that there is no moral use of sex with a condom and that condoms have always been a sign of immorality, be it prostitution, adultery, fornication, or marital contraception. Likewise, the author laments the success enjoyed by Planned Parenthood in achieving the social acceptance of marital contraception and sex outside of marriage. The complete social acceptance of homosexual activity, however, remains to be achieved. Magazines, newspapers, and television receive income in exchange for publishing or airing advertisements. Finding offensive advertisements which promote the use of condoms against HIV infection, the author recommends writing letters of complaint to the responsible media sources. If the television stations or publications in question continue to advertise condoms to the public, stop watching them or end one's subscriptions to the particular printed media. Such action taken collectively among many individuals will reduce product sales and income, and potentially sway corporate policy against condom ads. PMID:12345946

  14. The XXXXY Sex Chromosome Abnormality

    PubMed Central

    Barr, M. L.; Carr, D. H.; Pozsonyi, J.; Wilson, R. A.; Dunn, H. G.; Jacobson, T. S.; Miller, J. R.; Chown, B.

    1962-01-01

    The most common sex chromosome complex in sex chromatin-positive males with Klinefelter's syndrome is XXY. When the complex is XXYY or XXXY, the clinical findings do not seem to differ materially from those seen in XXY subjects, although more patients with these intersexual chromosome complements need to be studied to establish possible phenotypical expressions of the chromosomal variants. Two male children with an XXXXY sex chromosome abnormality are described. The data obtained from the study of these cases and five others described in the literature suggest that the XXXXY patient is likely to have congenital defects not usually seen in the common form of the Klinefelter syndrome. These include a triad of (1) skeletal anomalies (including radioulnar synostosis), (2) hypogenitalism (hypoplasia of penis and scrotum, incomplete descent of testes and defective prepubertal development of seminiferous tubules), and (3) greater risk of severe mental deficiency. That the conclusions are based on data from a small number of patients is emphasized, together with the need for a cytogenetic survey of a large control or unselected population. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7Fig. 8Fig. 9Fig. 10 PMID:13969480

  15. Condom ads promote illicit sex.

    PubMed

    Kippley, J F

    1994-01-01

    Written in 1987, this opinion was republished in the wake of US President Bill Clinton's AIDS prevention media campaign promoting condom use which began January 1994, targeted at young adults aged 18-25. The author staunchly opposes condom use even though he admits that people do not consider abstinence from sex to be a serious option for the prevention of HIV/STD infection. He believes that there is no moral use of sex with a condom and that condoms have always been a sign of immorality, be it prostitution, adultery, fornication, or marital contraception. Likewise, the author laments the success enjoyed by Planned Parenthood in achieving the social acceptance of marital contraception and sex outside of marriage. The complete social acceptance of homosexual activity, however, remains to be achieved. Magazines, newspapers, and television receive income in exchange for publishing or airing advertisements. Finding offensive advertisements which promote the use of condoms against HIV infection, the author recommends writing letters of complaint to the responsible media sources. If the television stations or publications in question continue to advertise condoms to the public, stop watching them or end one's subscriptions to the particular printed media. Such action taken collectively among many individuals will reduce product sales and income, and potentially sway corporate policy against condom ads.

  16. Galton and sex differences: an historical note.

    PubMed

    Buss, A R

    1976-07-01

    The psychological study of sex differences is a special area of interest within differential psychology. Differential psychology was launched as a scientific field of research in the latter half of the nineteenth century by Sir Francis Galton. Galton's early research on sex differences in psychological traits gives him the distinction of being the "father" of the modern study of sex differences. Galton's empirical findings and his interpretation of sex differences were heavily influenced by his Victorian sexist attitudes. The early history of the modern study of sex differences exemplifies the intimate relation between facts and values. PMID:797706

  17. Galton and sex differences: an historical note.

    PubMed

    Buss, A R

    1976-07-01

    The psychological study of sex differences is a special area of interest within differential psychology. Differential psychology was launched as a scientific field of research in the latter half of the nineteenth century by Sir Francis Galton. Galton's early research on sex differences in psychological traits gives him the distinction of being the "father" of the modern study of sex differences. Galton's empirical findings and his interpretation of sex differences were heavily influenced by his Victorian sexist attitudes. The early history of the modern study of sex differences exemplifies the intimate relation between facts and values.

  18. Individual, Interpersonal, and Social-Structural Correlates of Involuntary Sex Exchange Among Female Sex Workers in Two Mexico–U.S. Border Cities

    PubMed Central

    Goldenberg, S.M.; Rangel, G.; Staines, H.; Vera, A.; Lozada, R.; Nguyen, L.; Silverman, J.G.; Strathdee, S.A.

    2013-01-01

    Objective To investigate individual, interpersonal, and social-structural factors associated with involuntary sex exchange among female sex workers (FSWs) along the Mexico–U.S. border. Methods In 2010–2011, 214 FSWs from Tijuana (n=106) and Ciudad Juarez (n=108) aged ≥18 who reported lifetime use of heroin, cocaine, crack, or methamphetamine, having a stable partner, and having sold/traded sex in the past month completed quantitative surveys and HIV/STI testing. Logistic regression was used to identify correlates of involuntary sex exchange among FSWs. Results Of 214 FSWs, 31 (14.5%) reported involuntary sex exchange. These women were younger at sex work entry (Adjusted odds ratio [AOR]: 0.84/1 year increase, 95% CI: 0.72–0.97) and were significantly more likely to service clients whom they perceived to be HIV/STI-infected (AOR: 12.41, 95% CI: 3.15–48.91). Additionally, they were more likely to have clients who used drugs (AOR: 7.88, 95% CI: 1.52–41.00), report poor working conditions (AOR: 3.27, 95% CI: 1.03–10.31), and report a history of rape (AOR: 4.46, 1.43–13.91).] Conclusions Involuntary sex exchange is disproportionate among FSWs who begin to exchange sex at a younger age, and these women experience elevated risk of violence and HIV/STIs related to their clients’ behaviors and their working conditions. These data suggest the critical need for evidence-based approaches to preventing sexual exploitation of women and girls and to reducing harm among current sex workers. Multi-level interventions for sex workers and their clients that target interpersonal and social-structural risks (e.g., measures to improve safety and reduce exploitation within the workplace) are needed. PMID:23614997

  19. 'We are despised in the hospitals': sex workers' experiences of accessing health care in four African countries.

    PubMed

    Scorgie, Fiona; Nakato, Daisy; Harper, Eric; Richter, Marlise; Maseko, Sian; Nare, Prince; Smit, Jenni; Chersich, Matthew

    2013-01-01

    Sex workers in east and southern Africa are exposed to multiple occupational health and safety risks. Detailed understanding of barriers to accessing care would optimise design of improved services for this population. In this study, trained sex workers conducted 55 in-depth interviews and 12 focus group discussions with 106 female, 26 male and 4 transgender sex workers across 6 urban sites in Kenya, Zimbabwe, Uganda and South Africa. Data were analysed thematically, following an interpretive framework. Participants cited numerous unmet health needs, including diagnosis and treatment for sexually transmitted infections and insufficient access to condoms and lubricant. Denial of treatment for injuries following physical assault or rape and general hostility from public-sector providers was common. Resources permitting, many sex workers attended private services, citing higher quality and respect for dignity and confidentiality. Sex workers in southern Africa accessed specialised sex worker clinics, reporting mostly positive experiences. Across sites, participants called for additional targeted services, but also sensitisation and training of public-sector providers. Criminalisation of sex workers and associated stigmatisation, particularly of transgender and male sex workers, hinder HIV-prevention efforts and render access to mainstream healthcare precarious. Alongside law reform, sex worker-led peer outreach work should be strengthened and calls by sex workers for additional targeted services heeded. PMID:23414116

  20. Sex-Chromosome Homomorphy in Palearctic Tree Frogs Results from Both Turnovers and X-Y Recombination.

    PubMed

    Dufresnes, Christophe; Borzée, Amaël; Horn, Agnès; Stöck, Matthias; Ostini, Massimo; Sermier, Roberto; Wassef, Jérôme; Litvinchuck, Spartak N; Kosch, Tiffany A; Waldman, Bruce; Jang, Yikweon; Brelsford, Alan; Perrin, Nicolas

    2015-09-01

    Contrasting with birds and mammals, poikilothermic vertebrates often have homomorphic sex chromosomes, possibly resulting from high rates of sex-chromosome turnovers and/or occasional X-Y recombination. Strong support for the latter mechanism was provided by four species of European tree frogs, which inherited from a common ancestor (∼ 5 Ma) the same pair of homomorphic sex chromosomes (linkage group 1, LG1), harboring the candidate sex-determining gene Dmrt1. Here, we test sex linkage of LG1 across six additional species of the Eurasian Hyla radiation with divergence times ranging from 6 to 40 Ma. LG1 turns out to be sex linked in six of nine resolved cases. Mapping the patterns of sex linkage to the Hyla phylogeny reveals several transitions in sex-determination systems within the last 10 My, including one switch in heterogamety. Phylogenetic trees of DNA sequences along LG1 are consistent with occasional X-Y recombination in all species where LG1 is sex linked. These patterns argue against one of the main potential causes for turnovers, namely the accumulation of deleterious mutations on nonrecombining chromosomes. Sibship analyses show that LG1 recombination is strongly reduced in males from most species investigated, including some in which it is autosomal. Intrinsically low male recombination might facilitate the evolution of male heterogamety, and the presence of important genes from the sex-determination cascade might predispose LG1 to become a sex chromosome.

  1. Risk factors for HIV and syphilis infection among male sex workers who have sex with men: a cross-sectional study in Hangzhou, China, 2011

    PubMed Central

    Luo, Yan; Zhu, Chunyan; Chen, Shuchang; Geng, Qingshan; Fu, Rong; Li, Xiting; Xu, Ke; Cheng, Jie; Ding, Jianming

    2015-01-01

    Objective To investigate the prevalence and risk factors of HIV and syphilis infection among men who have sex with men (MSM) in male sex workers (MSW). Design Cross-sectional survey. Setting Hangzhou, China. Participants 259 MSW in MSM were recruited by respondent-driven sampling from May 2011 to December 2011.The inclusion criteria were: (1) age ≥18 years; (2) engaging in sex with men in the previous year and (3) willing to cooperate in the implementation of the study. Outcome measures HIV-related knowledge, high-risk behaviour and condom use. Results Among these MSW in MSM, 23.2% were infected with HIV and/or syphilis, 8.9% were infected only with HIV, 12.7% only with syphilis and 1.5% with HIV/syphilis co-infection; 96.6% sold sex to males, 8.9% bought sex from males and 15.4% sold sex to females; 49.0% had non-commercial sex behaviours with males and 24.3% with females. The rate of condom use while having commercial sex with clients was 86.9% and 53.3% (selling anal and oral sex to males, respectively), 95.5% (buying sex from males) and 77.5% (selling sex to females), respectively. Regarding their non-commercial sex behaviour, the rate of condom use was 77.2% (with males) and 49.2% (with females), respectively. Multivariate analysis showed that age >30 years (OR 1.055; 95% CIs 1.015 to 1.095) and having ≥10 non-commercial male sex partners (OR, 1.573; 95% CI 1.018 to 2.452) were significantly associated with HIV/syphilis infection, while heterosexuality (OR, 0.238; 95% CI 0.066 to 0.855) was significantly associated with a low HIV/syphilis infection rate. Conclusions The MSW in MSM population in Hangzhou has a high prevalence of HIV/syphilis infection, poor perceived risks of HIV and more engagement in unsafe sex with its clients and partners, in addition to a low rate of condom use. These risk factors may account for their relatively high infection rate of HIV/syphilis. PMID:25922096

  2. Current status of sexing mammalian spermatozoa.

    PubMed

    Seidel, George E; Garner, Duane L

    2002-12-01

    Thousands of offspring have now been produced via artificial insemination with spermatozoa sexed by flow cytometry and cell sorting. We are unaware of any other practical approach to sexing spermatozoa that maintains fertility. Accuracy of sexing usually is 85-95% in most species, but somewhat lower with human spermatozoa. Spermatozoa are sexed in series, one at a time, at routine rates of about 3000 live spermatozoa of each sex per second for most species, and nearly twice that rate under optimal conditions for some species. Owing to various constraints and statistical considerations, there appears to be an upper theoretical limit to sexing spermatozoa of about 10,000 live spermatozoa of each sex per second with current methodology. About a quarter of the spermatozoa processed are sexed; the rest are discarded in the process or lost due to logistical constraints. Spermatozoa undergo some damage during sorting, although much less in terms of viability than with routine cryopreservation; fertility is lower with sexed than control spermatozoa. Offspring from sexed spermatozoa appear to have no more abnormalities than do controls, and both groups grow and thrive similarly. Despite high costs and complex procedures, sexing spermatozoa, usually followed by cryopreservation, is being used commercially for cattle and horse production in several countries, and is used to produce girls to avoid X-chromosome-linked genetic diseases. PMID:12537000

  3. Bidirectional sex change in mushroom stony corals

    PubMed Central

    Loya, Yossi; Sakai, Kazuhiko

    2008-01-01

    Sex change occurs when an individual changes from one functional sex to another. The direction of sex change occurs mainly from male to female (protandry) or vice versa (protogyny), but sometimes may be bidirectional (repetitive). Here, for the first time in stony corals, we report on a protandrous sex change exhibited by two mushroom corals, Fungia repanda and Ctenactis echinata, with the latter also exhibiting bidirectional sex change. Compared with C. echinata, F. repanda exhibited relatively earlier sex change, significantly slower growth and higher mortality rates, in accordance with sex-allocation theory. Sex ratio in both the species was biased towards the first sex. The bidirectional sex change displayed by C. echinata greatly resembles that of dioecious plants that display labile sexuality in response to energetic and/or environmental constraints. We posit that, similar to these plants, in the studied corals, sex change increases their overall fitness, reinforcing the important role of reproductive plasticity in scleractinian corals in determining their evolutionary success. PMID:18611848

  4. Passive limb movement: evidence of mechanoreflex sex specificity

    PubMed Central

    McDaniel, John; Witman, Melissa A. H.; Richardson, Russell S.

    2013-01-01

    Previous studies have determined that premenopausal women exhibit an attenuated metaboreflex; however, little is known about sex specificity of the mechanoreflex. Thus, we sought to determine if sex differences exist in the central and peripheral hemodynamic responses to passive limb movement. Second-by-second measurements of heart rate, stroke volume, cardiac output (CO), mean arterial pressure, and femoral artery blood flow (FBF) were recorded during 3 min of supine passive knee extension in 24 young healthy subjects (12 women and 12 men). Normalization of CO and stroke volume to body surface area, expressed as cardiac index and stroke index, eliminated differences in baseline central hemodynamics, whereas, peripherally, basal FBF and femoral vascular conductance were similar between the sexes. In response to passive limb movement, women displayed significantly attenuated peak central hemodynamic responses compared with men (heart rate: 9.0 ± 1 vs. 14.8 ± 2% change, stroke index: 4.5 ± 0.6 vs. 7.8 ± 1.2% change, cardiac index: 9.6 ± 1 vs. 17.2 ± 2% change, all P < 0.05), whereas movement induced similar increases in peak FBF (167 ± 32 vs. 193 ± 17% change) and femoral vascular conductance (172 ± 31 vs. 203 ± 16% change) in both sexes (women vs. men, respectively). Additionally, there was a significant positive relationship between individual peak FBF and peak CO response to passive movement in men but not in women. Thus, although both sexes exhibited similar movement-induced hyperemia and peripheral vasodilatory function, the central hemodynamic response was blunted in women, implying an attenuated mechanoreflex. Therefore, this study reveals that, as already recognized with the metaboreflex, there is likely a sex-specific attenuation of the mechanoreflex in women. PMID:23086995

  5. Passive limb movement: evidence of mechanoreflex sex specificity.

    PubMed

    Ives, Stephen J; McDaniel, John; Witman, Melissa A H; Richardson, Russell S

    2013-01-01

    Previous studies have determined that premenopausal women exhibit an attenuated metaboreflex; however, little is known about sex specificity of the mechanoreflex. Thus, we sought to determine if sex differences exist in the central and peripheral hemodynamic responses to passive limb movement. Second-by-second measurements of heart rate, stroke volume, cardiac output (CO), mean arterial pressure, and femoral artery blood flow (FBF) were recorded during 3 min of supine passive knee extension in 24 young healthy subjects (12 women and 12 men). Normalization of CO and stroke volume to body surface area, expressed as cardiac index and stroke index, eliminated differences in baseline central hemodynamics, whereas, peripherally, basal FBF and femoral vascular conductance were similar between the sexes. In response to passive limb movement, women displayed significantly attenuated peak central hemodynamic responses compared with men (heart rate: 9.0 ± 1 vs. 14.8 ± 2% change, stroke index: 4.5 ± 0.6 vs. 7.8 ± 1.2% change, cardiac index: 9.6 ± 1 vs. 17.2 ± 2% change, all P < 0.05), whereas movement induced similar increases in peak FBF (167 ± 32 vs. 193 ± 17% change) and femoral vascular conductance (172 ± 31 vs. 203 ± 16% change) in both sexes (women vs. men, respectively). Additionally, there was a significant positive relationship between individual peak FBF and peak CO response to passive movement in men but not in women. Thus, although both sexes exhibited similar movement-induced hyperemia and peripheral vasodilatory function, the central hemodynamic response was blunted in women, implying an attenuated mechanoreflex. Therefore, this study reveals that, as already recognized with the metaboreflex, there is likely a sex-specific attenuation of the mechanoreflex in women.

  6. Causes and consequences of spatial variation in sex ratios in a declining bird species.

    PubMed

    Morrison, Catriona A; Robinson, Robert A; Clark, Jacquie A; Gill, Jennifer A

    2016-09-01

    Male-biased sex ratios occur in many bird species, particularly in those with small or declining populations, but the causes of these skews and their consequences for local population demography are rarely known. Within-species variation in sex ratios can help to identify the demographic and behavioural processes associated with such biases. Small populations may be more likely to have skewed sex ratios if sex differences in survival, recruitment or dispersal vary with local abundance. Analyses of species with highly variable local abundances can help to identify these mechanisms and the implications for spatial variation in demography. Many migratory bird species are currently undergoing rapid and severe declines in abundance in parts of their breeding ranges and thus have sufficient spatial variation in abundance to explore the extent of sex ratio biases, their causes and implications. Using national-scale bird ringing data for one such species (willow warbler, Phylloscopus trochilus), we show that sex ratios vary greatly across Britain and that male-biased sites are more frequent in areas of low abundance, which are now widespread across much of south and east England. These sex ratio biases are sufficient to impact local productivity, as the relative number of juveniles caught at survey sites declines significantly with increasing sex ratio skew. Sex differences in survival could influence this sex ratio variation, but we find little evidence for sex differences in survival increasing with sex ratio skew. In addition, sex ratios have become male-biased over the last two decades, but there are no such trends in adult survival rates for males or females. This suggests that lower female recruitment into low abundance sites is contributing to these skews. These findings suggest that male-biased sex ratios in small and declining populations can arise through local-scale sex differences in survival and dispersal, with females recruiting disproportionately into larger

  7. Additive lattice kirigami

    PubMed Central

    Castle, Toen; Sussman, Daniel M.; Tanis, Michael; Kamien, Randall D.

    2016-01-01

    Kirigami uses bending, folding, cutting, and pasting to create complex three-dimensional (3D) structures from a flat sheet. In the case of lattice kirigami, this cutting and rejoining introduces defects into an underlying 2D lattice in the form of points of nonzero Gaussian curvature. A set of simple rules was previously used to generate a wide variety of stepped structures; we now pare back these rules to their minimum. This allows us to describe a set of techniques that unify a wide variety of cut-and-paste actions under the rubric of lattice kirigami, including adding new material and rejoining material across arbitrary cuts in the sheet. We also explore the use of more complex lattices and the different structures that consequently arise. Regardless of the choice of lattice, creating complex structures may require multiple overlapping kirigami cuts, where subsequent cuts are not performed on a locally flat lattice. Our additive kirigami method describes such cuts, providing a simple methodology and a set of techniques to build a huge variety of complex 3D shapes. PMID:27679822

  8. Additive lattice kirigami

    PubMed Central

    Castle, Toen; Sussman, Daniel M.; Tanis, Michael; Kamien, Randall D.

    2016-01-01

    Kirigami uses bending, folding, cutting, and pasting to create complex three-dimensional (3D) structures from a flat sheet. In the case of lattice kirigami, this cutting and rejoining introduces defects into an underlying 2D lattice in the form of points of nonzero Gaussian curvature. A set of simple rules was previously used to generate a wide variety of stepped structures; we now pare back these rules to their minimum. This allows us to describe a set of techniques that unify a wide variety of cut-and-paste actions under the rubric of lattice kirigami, including adding new material and rejoining material across arbitrary cuts in the sheet. We also explore the use of more complex lattices and the different structures that consequently arise. Regardless of the choice of lattice, creating complex structures may require multiple overlapping kirigami cuts, where subsequent cuts are not performed on a locally flat lattice. Our additive kirigami method describes such cuts, providing a simple methodology and a set of techniques to build a huge variety of complex 3D shapes.

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

    PubMed

    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.

  10. Correlates of exchanging sex for drugs or money among women who use crack cocaine.

    PubMed

    Edwards, Jessica M; Halpern, Carolyn T; Wechsberg, Wendee M

    2006-10-01

    This study examined the correlates of trading sex for drugs or money among women who use crack cocaine. Using baseline data (n = 669) from a woman-focused HIV intervention study among African American women who use crack cocaine, we conducted logistic regression analysis to examine the odds of trading sex associated with distal and proximal factors. The results indicate that heavier crack use, homelessness, and unemployment are associated with trading sex. In addition, childhood abuse is associated with trading sex and this relationship is, in part, mediated by psychological distress. This suggests that distal factors may underlie the relationship between current variables and sex trading. These findings underscore the importance for public health interventions to address both distal and proximal factors that contribute to and/or co-occur with women's drug use which, in turn, may affect their HIV risk and overall well-being.

  11. Foster care history and HIV infection among drug-using African American female sex workers.

    PubMed

    Surratt, Hilary L; Kurtz, Steven P

    2012-05-01

    Foster care has been associated with increased HIV risk behaviors among youth, yet long-term association with HIV infection has not been examined. This study explored the associations between foster placement, victimization, mental health, onset of sex work and HIV infection among highly vulnerable female sex workers. 562 drug-involved African American women were enrolled into an intervention study to increase health services utilization and reduce HIV risk. Seventeen percent reported a history of foster placement. Foster history was associated with significantly lower educational attainment, higher victimization, and more severe mental health problems. Women with foster histories reported significantly earlier entry into paid sex work, with some 62% active in the sex trade before age 18. Multivariate analyses found that foster care was independently associated with HIV seropositivity, and that early sex work partially mediated this association. The potential long-term health vulnerabilities associated with foster placement are understudied and warrant additional research. PMID:21818654

  12. Foster Care History and HIV Infection among Drug-Using African American Female Sex Workers

    PubMed Central

    Surratt, Hilary L.; Kurtz, Steven P.

    2011-01-01

    Foster care has been associated with increased HIV risk behaviors among youth, yet long-term association with HIV infection has not been examined. This study explored the associations between foster placement, victimization, mental health, onset of sex work and HIV infection among highly vulnerable female sex workers. 562 drug-involved African American women were enrolled into an intervention study to increase health services utilization and reduce HIV risk. Seventeen percent reported a history of foster placement. Foster history was associated with significantly lower educational attainment, higher victimization, and more severe mental health problems. Women with foster histories reported significantly earlier entry into paid sex work, with some 62% active in the sex trade before age 18. Multivariate analyses found that foster care was independently associated with HIV seropositivity, and that early sex work partially mediated this association. The potential long-term health vulnerabilities associated with foster placement are understudied and warrant additional research. PMID:21818654

  13. Sex-sorting sperm by flow cytometry in pigs: issues and perspectives.

    PubMed

    Vazquez, J M; Parrilla, I; Roca, J; Gil, M A; Cuello, C; Vazquez, J L; Martínez, E A

    2009-01-01

    Several hundred thousand offspring of preselected sex of various species have been born since sperm sexing technology based on flow cytometric sorting of X- and Y-chromosome-bearing sperm and DNA was first demonstrated in 1989. The advantages derived from application of sexing technology to commercial dairy cattle production have been demonstrated worldwide. Utilizing sex-sorting technology for pig production systems offers many similar advantages. However, several factors currently limit implementation of sexing technology in pigs. Anatomical and physiological features inherent to the female pig, together with the relatively low sperm output of a flow sorter, are the main limitations to widespread use of this technology in pig production systems. This review analyzes the factors that limit the efficiency of sperm sorting technology for commercial swine production. In addition, this review discusses recent innovations in technical instrumentation and applied reproductive techniques that may help to overcome some of these limitations. PMID:18977521

  14. Correlates of exchanging sex for drugs or money among women who use crack cocaine.

    PubMed

    Edwards, Jessica M; Halpern, Carolyn T; Wechsberg, Wendee M

    2006-10-01

    This study examined the correlates of trading sex for drugs or money among women who use crack cocaine. Using baseline data (n = 669) from a woman-focused HIV intervention study among African American women who use crack cocaine, we conducted logistic regression analysis to examine the odds of trading sex associated with distal and proximal factors. The results indicate that heavier crack use, homelessness, and unemployment are associated with trading sex. In addition, childhood abuse is associated with trading sex and this relationship is, in part, mediated by psychological distress. This suggests that distal factors may underlie the relationship between current variables and sex trading. These findings underscore the importance for public health interventions to address both distal and proximal factors that contribute to and/or co-occur with women's drug use which, in turn, may affect their HIV risk and overall well-being. PMID:17067253

  15. The mechanism of sex determination in vertebrates-are sex steroids the key-factor?

    PubMed

    Nakamura, Masahisa

    2010-08-01

    In many vertebrate species, sex is determined at fertilization of zygotes by sex chromosome composition, knows as genotypic sex determination (GSD). But in some species-fish, amphibians and reptiles-sex is determined by environmental factors; in particular by temperature-dependent sex determination (TSD). However, little is known about the mechanisms involved in TSD and GSD. How does TSD differ from GSD? As is well known, genes that activated downstream of sex-determining genes are conserved throughout all classes of vertebrates. What is the main factor that determines sex, then? Sex steroids can reverse sex of several species of vertebrate; estrogens induce the male-to-female sex-reversal, whereas androgens do the female-to-male sex-reversal. For such sex-reversal, a functioning sex-determining gene is not required. However, in R. rugosa CYP19 (P450 aromatase) is expressed at high levels in indifferent gonads before phenotypic sex determination, and the gene is also active in the bipotential gonad of females before sex determination. Thus, we may predict that an unknown factor, a common transcription factor locates on the X and/or W chromosome, intervenes directly or indirectly in the transcriptional up-regulation of the CYP19 gene for feminization in species of vertebrates with both TSD and GSD. Similarly, an unknown factor on the Z and/or Y chromosome probably intervenes directly or indirectly in the regulation of androgen biosynthesis for masculinization. In both cases, a sex-determining gene is not always necessary for sex determination. Taken together, sex steroids may be the key-factor for sex determination in some species of vertebrates.

  16. Committee Opinion No. 574: Marriage equality for same-sex couples.

    PubMed

    2013-09-01

    Same-sex couples encounter barriers to health care that include concerns about confidentiality and disclosure, stigma and discriminatory attitudes and treatment, limited access to health care and health insurance, and often a limited understanding of their health risks. Same-sex couples and their families are adversely affected by the lack of legal recognition of their relationships, a problem with major implications for the health of same-sex couples and their families. Tangible harm has come from the lack of financial and health care protections granted to legal spouses, and children are harmed by the lack of protections afforded to families in which partners are married. However, the recent Supreme Court ruling, The United States v Windsor, which afforded equal treatment for legally married same-sex couples will provide many important health and financial benefits. Evidence suggests that marriage confers health benefits to individuals and families, yet a sizable proportion of individuals do not experience these health benefits because of their sexual orientation. Additional data suggest that same-sex couples who live in states with bans on same-sex unions experience adverse health outcomes. Civil marriage is currently available to same-sex couples in only thirteen states and the District of Columbia and honored by one state. The American College of Obstetricians and Gynecologists endorses marriage equality for same-sex couples and equal treatment for these couples and their families and applauds the Supreme Court's decision as an important step in improving access to benefits received by legally married same-sex couples. However, additional efforts are necessary to ensure that same-sex couples in every state can receive these same benefits.

  17. The evolution of sex is favoured during adaptation to new environments.

    PubMed

    Becks, Lutz; Agrawal, Aneil F

    2012-01-01

    Both theory and experiments have demonstrated that sex can facilitate adaptation, potentially yielding a group-level advantage to sex. However, it is unclear whether this process can help solve the more difficult problem of the maintenance of sex within populations. Using experimental populations of the facultatively sexual rotifer Brachionus calyciflorus, we show that rates of sex evolve to higher levels during adaptation but then decline as fitness plateaus. To assess the fitness consequences of genetic mixing, we directly compare the fitnesses of sexually and asexually derived genotypes that naturally occur in our experimental populations. Sexually derived genotypes are more fit than asexually derived genotypes when adaptive pressures are strong, but this pattern reverses as the pace of adaptation slows, matching the pattern of evolutionary change in the rate of sex. These fitness assays test the net effect of sex but cannot be used to disentangle whether selection on sex arises because highly sexual lineages become associated with different allele combinations or with different allele frequencies than less sexual lineages (i.e., "short-" or "long-term" effects, respectively). We infer which of these mechanisms provides an advantage to sex by performing additional manipulations to obtain fitness distributions of sexual and asexual progeny arrays from unbiased parents (rather than from naturally occurring, and thereby evolutionarily biased, parents). We find evidence that sex breaks down adaptive gene combinations, resulting in lower average fitness of sexual progeny (i.e., a short-term disadvantage to sex). As predicted by theory, the advantage to sex arises because sexually derived progeny are more variable in fitness, allowing for faster adaptation. This "long-term advantage" builds over multiple generations, eventually resulting in higher fitness of sexual types.

  18. Genomic Instability of the Sex-Determining Locus in Atlantic Salmon (Salmo salar).

    PubMed

    Lubieniecki, Krzysztof P; Lin, Song; Cabana, Emily I; Li, Jieying; Lai, Yvonne Y Y; Davidson, William S

    2015-09-22

    Atlantic salmon and rainbow trout, like other members of the subfamily Salmoninae, are gonochoristic with male heterogamety. The finding that sex-linked genetic markers varied between species suggested that the sex-determining gene differs among salmonid species, or that there is one sex-determining gene that has the capacity to move around the genome. The discovery of sdY, the sex-determining gene in rainbow trout, and its presence in many male salmonids gave support to the latter. Additional evidence for a salmonid-specific, sex-determining jumping gene came from the mapping of the sex-determining locus to three different chromosomes in Tasmanian male Atlantic salmon lineages. To characterize the sex-determining region, we isolated three sdY containing BACs from an Atlantic salmon male library. Sequencing of these BACs yielded two contigs, one of which contained the sdY gene. Sequence analysis of the borders of male-specific and female/male common regions revealed highly repetitive sequences associated with mobile elements, which may allow an sdY cassette to jump around the genome. FISH analysis using a BAC or a plasmid containing the sdY gene showed that the sdY gene did indeed localize to the chromosomes where SEX had been mapped in different Tasmanian Atlantic salmon families. Moreover, the plasmid sdY gene probe hybridized primarily to one of the sex chromosomes as would be expected of a male-specific gene. Our results suggest that a common salmonid sex-determining gene (sdY) can move between three specific loci on chromosomes 2, 3, and 6, giving the impression that there are multiple SEX loci both within and between salmonid species.

  19. Differences in Gay Male Couples' Use of Drugs and Alcohol With Sex by Relationship HIV Status.

    PubMed

    Mitchell, Jason W

    2016-07-01

    Prior studies with men who have sex with men have documented a strong association between substance use with sex and risk for acquisition of HIV. However, few studies have been conducted about gay male couples' use of substances with sex, despite the fact that between one third and two thirds of men who have sex with men acquire HIV from their relationship partners. The present study sought to (1) describe whether one or both partners in the male couple uses substances with sex-by substance type-within and/or outside of their relationship, and (2) assess whether differences exist in those who use substances with sex within and outside the relationship by the couples' HIV status. Dyadic data for this analysis were collected in the United States from a nation-wide cross-sectional Internet study about male couples' relationships and behaviors. Couple-level descriptive and comparative analyses were employed with 361 male couples. Except for alcohol, most couples did not use substances with sex. Of those who did, rates of who used it with sex and substance type within the relationship varied; most couples only had one partner who used substances with sex outside the relationship. Significantly higher proportions of concordantly HIV-negative and HIV-positive couples had both partners who used substances (all types) with sex within their relationship over discordant couples. Most couples had one partner who used outside the relationship; only marijuana and erectile dysfunction medication use with sex significantly differed by couples' HIV status. Findings indicate the need to conduct additional research for prevention development.

  20. Genomic Instability of the Sex-Determining Locus in Atlantic Salmon (Salmo salar)

    PubMed Central

    Lubieniecki, Krzysztof P.; Lin, Song; Cabana, Emily I.; Li, Jieying; Lai, Yvonne Y. Y.; Davidson, William S.

    2015-01-01

    Atlantic salmon and rainbow trout, like other members of the subfamily Salmoninae, are gonochoristic with male heterogamety. The finding that sex-linked genetic markers varied between species suggested that the sex-determining gene differs among salmonid species, or that there is one sex-determining gene that has the capacity to move around the genome. The discovery of sdY, the sex-determining gene in rainbow trout, and its presence in many male salmonids gave support to the latter. Additional evidence for a salmonid-specific, sex-determining jumping gene came from the mapping of the sex-determining locus to three different chromosomes in Tasmanian male Atlantic salmon lineages. To characterize the sex-determining region, we isolated three sdY containing BACs from an Atlantic salmon male library. Sequencing of these BACs yielded two contigs, one of which contained the sdY gene. Sequence analysis of the borders of male-specific and female/male common regions revealed highly repetitive sequences associated with mobile elements, which may allow an sdY cassette to jump around the genome. FISH analysis using a BAC or a plasmid containing the sdY gene showed that the sdY gene did indeed localize to the chromosomes where SEX had been mapped in different Tasmanian Atlantic salmon families. Moreover, the plasmid sdY gene probe hybridized primarily to one of the sex chromosomes as would be expected of a male-specific gene. Our results suggest that a common salmonid sex-determining gene (sdY) can move between three specific loci on chromosomes 2, 3, and 6, giving the impression that there are multiple SEX loci both within and between salmonid species. PMID:26401030

  1. Sex differences in the vomeronasal system.

    PubMed

    Guillamón, A; Segovia, S

    1997-01-01

    In the early eighties we found sex differences in the vomeronasal organ (VNO) and hypothesized that the vomeronasal system (VNS), a complex neural network involved in the control of reproductive behavior, might be sexually dimorphic. At that time sex differences had already been described for some structures that receive VNO input, such as the medial amygdala, the medial preoptic area, the ventromedial hypothalamic nucleus, and the ventral region of the premammillary nucleus. Since then, we have shown sex differences in the accessory olfactory bulb (AOB), the bed nucleus of the accessory olfactory tract (BAOT), and the bed nucleus of the stria terminalis (BST). When new VNS connections were found, all of them ended in nuclei that present sex differences. In general, sex differences in the olfactory system show two morphological patterns: one in which males present greater morphological measures than females, and just the opposite. To explain the morphometric measures of males in the latter, it has been hypothesized that androgens serve as inhibitors. Our work on the involvement of the GABA(A) receptor in the development of AOB and maternal behavior sex differences also suggests that neonatal changes in neuronal membrane permeability to the ion Cl- differences. This might be the first animal model to help us to understand the situation in which human genetic and gonadal sex do not agree with brain and behavioral sex. Finally, we stress that sex differences in the VNS constitute a neurofunctional model for understanding sex differences in reproductive behaviors.

  2. Perils and pitfalls of reporting sex differences.

    PubMed

    Maney, Donna L

    2016-02-19

    The idea of sex differences in the brain both fascinates and inflames the public. As a result, the communication and public discussion of new findings is particularly vulnerable to logical leaps and pseudoscience. A new US National Institutes of Health policy to consider both sexes in almost all preclinical research will increase the number of reported sex differences and thus the risk that research in this important area will be misinterpreted and misrepresented. In this article, I consider ways in which we might reduce that risk, for example, by (i) employing statistical tests that reveal the extent to which sex explains variation, rather than whether or not the sexes 'differ', (ii) properly characterizing the frequency distributions of scores or dependent measures, which nearly always overlap, and (iii) avoiding speculative functional or evolutionary explanations for sex-based variation, which usually invoke logical fallacies and perpetuate sex stereotypes. Ultimately, the factor of sex should be viewed as an imperfect, temporary proxy for yet-unknown factors, such as hormones or sex-linked genes, that explain variation better than sex. As scientists, we should be interested in discovering and understanding the true sources of variation, which will be more informative in the development of clinical treatments. PMID:26833839

  3. Technology, normalisation and male sex work.

    PubMed

    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.

  4. Technology, normalisation and male sex work.

    PubMed

    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. PMID:25215634

  5. Comparative Transcriptome Analysis Reveals Sex-Biased Gene Expression in Juvenile Chinese Mitten Crab Eriocheir sinensis

    PubMed Central

    Liu, Yuan; Hui, Min; Cui, Zhaoxia; Luo, Danli; Song, Chengwen; Li, Yingdong; Liu, Lei

    2015-01-01

    Sex-biased genes are considered to account for most of phenotypic differences between males and females. In order to explore the sex-biased gene expression in crab, we performed the whole-body transcriptome analysis in male and female juveniles of the Chinese mitten crab Eriocheir sinensis using next-generation sequencing technology. Of the 23,349 annotated unigenes, 148 were identified as sex-related genes. A total of 29 candidate genes involved in primary sex determination pathways were detected, indicating the sex determination cascade of the mitten crab might be more complex than previously supposed. Differential expression analysis showed 448 differentially expressed genes (DEGs) between the two transcriptomes. Most of DEGs were involved in processes such as metabolism and immunity, and not associated with obvious sexual function. The pathway predominantly enriched for DEGs were related to lysosome, which might reflect the differences in metabolism between males and females. Of the immune DGEs, 18 up-regulated genes in females were humoral immune factors, and eight up-regulated genes in males were pattern recognition receptors, suggesting sex differences of immune defense might exist in the mitten crab. In addition, two reproduction-related genes, vitellogenin and insulin-like androgenic gland factor, were identified to express in both sexes but with significantly higher level in males. Our research provides the first whole-body RNA sequencing of sex-specific transcriptomes for juvenile E. sinensis and will facilitate further studies on molecular mechanisms of crab sexual dimorphism. PMID:26193085

  6. Inbreeding removes sex differences in lifespan in a population of Drosophila melanogaster

    PubMed Central

    Green, Jared; Sepil, Irem; Pizzari, Tommaso; Wigby, Stuart

    2016-01-01

    Sex differences in ageing rates and lifespan are common in nature, and an enduring puzzle for evolutionary biology. One possibility is that sex-specific mortality rates may result from recessive deleterious alleles in ‘unguarded’ heterogametic X or Z sex chromosomes (the unguarded X hypothesis). Empirical evidence for this is, however, limited. Here, we test a fundamental prediction of the unguarded X hypothesis in Drosophila melanogaster, namely that inbreeding shortens lifespan more in females (the homogametic sex in Drosophila) than in males. To test for additional sex-specific social effects, we studied the lifespan of males and females kept in isolation, in related same-sex groups, and in unrelated same-sex groups. As expected, outbred females outlived outbred males and inbreeding shortened lifespan. However, inbreeding-mediated reductions in lifespan were stronger for females, such that lifespan was similar in inbred females and males. We also show that the social environment, independent of inbreeding, affected male, but not female lifespan. In conjunction with recent studies, the present results suggest that asymmetric inheritance mechanisms may play an important role in the evolution of sex-specific lifespan and that social effects must be considered explicitly when studying these fundamental patterns. PMID:27354712

  7. Inbreeding removes sex differences in lifespan in a population of Drosophila melanogaster.

    PubMed

    Carazo, Pau; Green, Jared; Sepil, Irem; Pizzari, Tommaso; Wigby, Stuart

    2016-06-01

    Sex differences in ageing rates and lifespan are common in nature, and an enduring puzzle for evolutionary biology. One possibility is that sex-specific mortality rates may result from recessive deleterious alleles in 'unguarded' heterogametic X or Z sex chromosomes (the unguarded X hypothesis). Empirical evidence for this is, however, limited. Here, we test a fundamental prediction of the unguarded X hypothesis in Drosophila melanogaster, namely that inbreeding shortens lifespan more in females (the homogametic sex in Drosophila) than in males. To test for additional sex-specific social effects, we studied the lifespan of males and females kept in isolation, in related same-sex groups, and in unrelated same-sex groups. As expected, outbred females outlived outbred males and inbreeding shortened lifespan. However, inbreeding-mediated reductions in lifespan were stronger for females, such that lifespan was similar in inbred females and males. We also show that the social environment, independent of inbreeding, affected male, but not female lifespan. In conjunction with recent studies, the present results suggest that asymmetric inheritance mechanisms may play an important role in the evolution of sex-specific lifespan and that social effects must be considered explicitly when studying these fundamental patterns. PMID:27354712

  8. Systematic Analysis of Adverse Event Reports for Sex Differences in Adverse Drug Events.

    PubMed

    Yu, Yue; Chen, Jun; Li, Dingcheng; Wang, Liwei; Wang, Wei; Liu, Hongfang

    2016-04-22

    Increasing evidence has shown that sex differences exist in Adverse Drug Events (ADEs). Identifying those sex differences in ADEs could reduce the experience of ADEs for patients and could be conducive to the development of personalized medicine. In this study, we analyzed a normalized US Food and Drug Administration Adverse Event Reporting System (FAERS). Chi-squared test was conducted to discover which treatment regimens or drugs had sex differences in adverse events. Moreover, reporting odds ratio (ROR) and P value were calculated to quantify the signals of sex differences for specific drug-event combinations. Logistic regression was applied to remove the confounding effect from the baseline sex difference of the events. We detected among 668 drugs of the most frequent 20 treatment regimens in the United States, 307 drugs have sex differences in ADEs. In addition, we identified 736 unique drug-event combinations with significant sex differences. After removing the confounding effect from the baseline sex difference of the events, there are 266 combinations remained. Drug labels or previous studies verified some of them while others warrant further investigation.

  9. Female Salix viminalis are more severely infected by Melampsora spp. but neither sex experiences associational effects.

    PubMed

    Moritz, Kim K; Björkman, Christer; Parachnowitsch, Amy L; Stenberg, Johan A

    2016-02-01

    Associational effects of plant genotype or species on plant biotic interactions are common, not least for disease spread, but associational effects of plant sex on interactions have largely been ignored. Sex in dioecious plants can affect biotic interactions with herbivores and pollinators; however, its effects on plant-pathogen interactions are understudied and associational effects are unknown. In a replicated field experiment, we assessed Melampsora spp. leaf rust infection in monosexual and mixed sex plots of dioecious Salix viminalis L. to determine whether plant sex has either direct or associational effects on infection severity. We found no differences in Melampsora spp. infection severity among sexual monocultures and mixtures in our field experiment. However, female plants were overall more severely infected. In addition, we surveyed previous studies of infection in S. viminalis clones and reevaluated the studies after we assigned sex to the clones. We found that females were generally more severely infected, as in our field study. Similarly, in a survey of studies on sex-biased infection in dioecious plants, we found more female-biased infections in plant-pathogen pairs. We conclude that there was no evidence for associational plant sex effects of neighboring conspecifics for either females or males on infection severity. Instead, plant sex effects on infection act at an individual plant level. Our findings also suggest that female plants may in general be more severely affected by fungal pathogens than males. PMID:26839685

  10. Systematic Analysis of Adverse Event Reports for Sex Differences in Adverse Drug Events

    PubMed Central

    Yu, Yue; Chen, Jun; Li, Dingcheng; Wang, Liwei; Wang, Wei; Liu, Hongfang

    2016-01-01

    Increasing evidence has shown that sex differences exist in Adverse Drug Events (ADEs). Identifying those sex differences in ADEs could reduce the experience of ADEs for patients and could be conducive to the development of personalized medicine. In this study, we analyzed a normalized US Food and Drug Administration Adverse Event Reporting System (FAERS). Chi-squared test was conducted to discover which treatment regimens or drugs had sex differences in adverse events. Moreover, reporting odds ratio (ROR) and P value were calculated to quantify the signals of sex differences for specific drug-event combinations. Logistic regression was applied to remove the confounding effect from the baseline sex difference of the events. We detected among 668 drugs of the most frequent 20 treatment regimens in the United States, 307 drugs have sex differences in ADEs. In addition, we identified 736 unique drug-event combinations with significant sex differences. After removing the confounding effect from the baseline sex difference of the events, there are 266 combinations remained. Drug labels or previous studies verified some of them while others warrant further investigation. PMID:27102014

  11. Inbreeding removes sex differences in lifespan in a population of Drosophila melanogaster.

    PubMed

    Carazo, Pau; Green, Jared; Sepil, Irem; Pizzari, Tommaso; Wigby, Stuart

    2016-06-01

    Sex differences in ageing rates and lifespan are common in nature, and an enduring puzzle for evolutionary biology. One possibility is that sex-specific mortality rates may result from recessive deleterious alleles in 'unguarded' heterogametic X or Z sex chromosomes (the unguarded X hypothesis). Empirical evidence for this is, however, limited. Here, we test a fundamental prediction of the unguarded X hypothesis in Drosophila melanogaster, namely that inbreeding shortens lifespan more in females (the homogametic sex in Drosophila) than in males. To test for additional sex-specific social effects, we studied the lifespan of males and females kept in isolation, in related same-sex groups, and in unrelated same-sex groups. As expected, outbred females outlived outbred males and inbreeding shortened lifespan. However, inbreeding-mediated reductions in lifespan were stronger for females, such that lifespan was similar in inbred females and males. We also show that the social environment, independent of inbreeding, affected male, but not female lifespan. In conjunction with recent studies, the present results suggest that asymmetric inheritance mechanisms may play an important role in the evolution of sex-specific lifespan and that social effects must be considered explicitly when studying these fundamental patterns.

  12. Comparative Transcriptome Analysis Reveals Sex-Biased Gene Expression in Juvenile Chinese Mitten Crab Eriocheir sinensis.

    PubMed

    Liu, Yuan; Hui, Min; Cui, Zhaoxia; Luo, Danli; Song, Chengwen; Li, Yingdong; Liu, Lei

    2015-01-01

    Sex-biased genes are considered to account for most of phenotypic differences between males and females. In order to explore the sex-biased gene expression in crab, we performed the whole-body transcriptome analysis in male and female juveniles of the Chinese mitten crab Eriocheir sinensis using next-generation sequencing technology. Of the 23,349 annotated unigenes, 148 were identified as sex-related genes. A total of 29 candidate genes involved in primary sex determination pathways were detected, indicating the sex determination cascade of the mitten crab might be more complex than previously supposed. Differential expression analysis showed 448 differentially expressed genes (DEGs) between the two transcriptomes. Most of DEGs were involved in processes such as metabolism and immunity, and not associated with obvious sexual function. The pathway predominantly enriched for DEGs were related to lysosome, which might reflect the differences in metabolism between males and females. Of the immune DGEs, 18 up-regulated genes in females were humoral immune factors, and eight up-regulated genes in males were pattern recognition receptors, suggesting sex differences of immune defense might exist in the mitten crab. In addition, two reproduction-related genes, vitellogenin and insulin-like androgenic gland factor, were identified to express in both sexes but with significantly higher level in males. Our research provides the first whole-body RNA sequencing of sex-specific transcriptomes for juvenile E. sinensis and will facilitate further studies on molecular mechanisms of crab sexual dimorphism.

  13. Meditation Awareness Training for the Treatment of Sex Addiction: A Case Study.

    PubMed

    Van Gordon, William; Shonin, Edo; Griffiths, Mark D

    2016-06-01

    Background Sex addiction is a disorder that can have serious adverse functional consequences. Treatment effectiveness research for sex addiction is currently underdeveloped, and interventions are generally based on the guidelines for treating other behavioral (as well as chemical) addictions. Consequently, there is a need to clinically evaluate tailored treatments that target the specific symptoms of sex addiction. It has been proposed that second-generation mindfulness-based interventions (SG-MBIs) may be an appropriate treatment for sex addiction because in addition to helping individuals increase perceptual distance from craving for desired objects and experiences, some SG-MBIs specifically contain meditations intended to undermine attachment to sex and/or the human body. The current study conducts the first clinical investigation into the utility of mindfulness for treating sex addiction. Case presentation An in-depth clinical case study was conducted involving an adult male suffering from sex addiction that underwent treatment utilizing an SG-MBI known as Meditation Awareness Training (MAT). Following completion of MAT, the participant demonstrated clinically significant improvements in addictive sexual behavior, as well as reductions in depression and psychological distress. The MAT intervention also led to improvements in sleep quality, job satisfaction, and non-attachment to self and experiences. Salutary outcomes were maintained at 6-month follow-up. Discussion and conclusion The current study extends the literature exploring the applications of mindfulness for treating behavioral addiction, and findings indicate that further clinical investigation into the role of mindfulness for treating sex addiction is warranted.

  14. Sex differences in steroidogenesis in skeletal muscle following a single bout of exercise in rats.

    PubMed

    Aizawa, Katsuji; Iemitsu, Motoyuki; Otsuki, Takeshi; Maeda, Seiji; Miyauchi, Takashi; Mesaki, Noboru

    2008-01-01

    Sex steroid hormones, such as testosterone and estradiol, play important roles in developing both strength and mass of skeletal muscle. Recently, we demonstrated that skeletal muscle can synthesize sex steroid hormones. Whether there are sex differences in basal steroidogenesis or acute exercise-induced alterations of steroidogenesis in the skeletal muscle is unknown. We examined sex differences in the levels of testosterone, estradiol, and steroidogenesis-related enzymes, such as 17beta-hydroxysteroid dehydrogenase (HSD), 3beta-HSD, and aromatase cytochrome P-450 (P450arom), in the skeletal muscle at rest and after exercise. We studied the gastrocnemius muscles of resting rats (10 wk old) and exercised rats (10 wk old, treadmill running, 30 m/min, 30 min). Basal muscular testosterone levels were higher in males than females, whereas estradiol did not differ between sexes. Additionally, 17beta-HSD, 3beta-HSD, and P450arom transcript and protein expression were greater in females. After acute exercise, testosterone levels and 17beta-HSD expression increased in muscle in both sexes. By comparison, muscular estradiol levels increased in males following exercise but were unchanged in females. Expression of P450arom, which regulates estrogen synthesis, increased after acute exercise in males but decreased after exercise in females. Thus a single bout of exercise can influence the steroidogenic system in skeletal muscle, and these alterations differ between sexes. The acute exercise-induced alteration of steroidogenic enzymes may enhance the local steroidogenesis in the skeletal muscle in both sexes.

  15. Meditation Awareness Training for the Treatment of Sex Addiction: A Case Study.

    PubMed

    Van Gordon, William; Shonin, Edo; Griffiths, Mark D

    2016-06-01

    Background Sex addiction is a disorder that can have serious adverse functional consequences. Treatment effectiveness research for sex addiction is currently underdeveloped, and interventions are generally based on the guidelines for treating other behavioral (as well as chemical) addictions. Consequently, there is a need to clinically evaluate tailored treatments that target the specific symptoms of sex addiction. It has been proposed that second-generation mindfulness-based interventions (SG-MBIs) may be an appropriate treatment for sex addiction because in addition to helping individuals increase perceptual distance from craving for desired objects and experiences, some SG-MBIs specifically contain meditations intended to undermine attachment to sex and/or the human body. The current study conducts the first clinical investigation into the utility of mindfulness for treating sex addiction. Case presentation An in-depth clinical case study was conducted involving an adult male suffering from sex addiction that underwent treatment utilizing an SG-MBI known as Meditation Awareness Training (MAT). Following completion of MAT, the participant demonstrated clinically significant improvements in addictive sexual behavior, as well as reductions in depression and psychological distress. The MAT intervention also led to improvements in sleep quality, job satisfaction, and non-attachment to self and experiences. Salutary outcomes were maintained at 6-month follow-up. Discussion and conclusion The current study extends the literature exploring the applications of mindfulness for treating behavioral addiction, and findings indicate that further clinical investigation into the role of mindfulness for treating sex addiction is warranted. PMID:27348560

  16. Female Salix viminalis are more severely infected by Melampsora spp. but neither sex experiences associational effects.

    PubMed

    Moritz, Kim K; Björkman, Christer; Parachnowitsch, Amy L; Stenberg, Johan A

    2016-02-01

    Associational effects of plant genotype or species on plant biotic interactions are common, not least for disease spread, but associational effects of plant sex on interactions have largely been ignored. Sex in dioecious plants can affect biotic interactions with herbivores and pollinators; however, its effects on plant-pathogen interactions are understudied and associational effects are unknown. In a replicated field experiment, we assessed Melampsora spp. leaf rust infection in monosexual and mixed sex plots of dioecious Salix viminalis L. to determine whether plant sex has either direct or associational effects on infection severity. We found no differences in Melampsora spp. infection severity among sexual monocultures and mixtures in our field experiment. However, female plants were overall more severely infected. In addition, we surveyed previous studies of infection in S. viminalis clones and reevaluated the studies after we assigned sex to the clones. We found that females were generally more severely infected, as in our field study. Similarly, in a survey of studies on sex-biased infection in dioecious plants, we found more female-biased infections in plant-pathogen pairs. We conclude that there was no evidence for associational plant sex effects of neighboring conspecifics for either females or males on infection severity. Instead, plant sex effects on infection act at an individual plant level. Our findings also suggest that female plants may in general be more severely affected by fungal pathogens than males.

  17. Why are sex and gender important to basic physiology and translational and individualized medicine?

    PubMed Central

    2014-01-01

    Sex refers to biological differences between men and women. Although sex is a fundamental aspect of human physiology that splits the population in two approximately equal halves, this essential biological variable is rarely considered in the design of basic physiological studies, in translating findings from basic science to clinical research, or in developing personalized medical strategies. Contrary to sex, gender refers to social and cultural factors related to being a man or a woman in a particular historical and cultural context. Unfortunately, gender is often used incorrectly by scientists and clinical investigators as synonymous with sex. This article clarifies the definition of sex and gender and reviews evidence showing how sex and gender interact with each other to influence etiology, presentation of disease, and treatment outcomes. In addition, strategies to improve the inclusion of female and male human beings in preclinical and clinical studies will be presented, and the importance of embedding concepts of sex and gender into postgraduate and medical curricula will be discussed. Also, provided is a list of resources for educators. In the history of medical concepts, physiologists have provided pivotal contributions to understanding health and disease processes. In the future, physiologists should provide the evidence for advancing personalized medicine and for reducing sex and gender disparities in health care. PMID:24414073

  18. Declining Segregation of Same-Sex Partners: Evidence from Census 2000 and 2010

    PubMed Central

    2013-01-01

    Despite recent media and scholarly attention describing the “disappearance” of traditionally gay neighborhoods, urban scholars have yet to quantify the segregation of same-sex partners and determine whether declining segregation from different-sex partners is a wide-spread trend. Focusing on the 100 most populous places in the United States, I use data from the 2000 and 2010 Decennial Census to examine the segregation of same-sex partners over time and its place-level correlates. I estimate linear regression models to examine the role of four place characteristics in particular: average levels of education, aggregate trends in the family life cycle of same-sex partners, violence and social hostility motivated by sexual orientation bias, and representation of same-sex partners in the overall population. On average, same-sex partners were less segregated from different-sex partners in 2010 than in 2000, and the vast majority of same-sex partners lived in environments of declining segregation. Segregation was lower and declined more rapidly in places that had a greater percentage of graduate degree holders. In addition, segregation of female partners was lower in places that had a greater share of female partner households with children. These findings suggest that sexual orientation should be considered alongside economic status, race, and ethnicity as an important factor that contributes to neighborhood differentiation and urban spatial inequality. PMID:24187412

  19. Declining Segregation of Same-Sex Partners: Evidence from Census 2000 and 2010.

    PubMed

    Spring, Amy L

    2013-10-01

    Despite recent media and scholarly attention describing the "disappearance" of traditionally gay neighborhoods, urban scholars have yet to quantify the segregation of same-sex partners and determine whether declining segregation from different-sex partners is a wide-spread trend. Focusing on the 100 most populous places in the United States, I use data from the 2000 and 2010 Decennial Census to examine the segregation of same-sex partners over time and its place-level correlates. I estimate linear regression models to examine the role of four place characteristics in particular: average levels of education, aggregate trends in the family life cycle of same-sex partners, violence and social hostility motivated by sexual orientation bias, and representation of same-sex partners in the overall population. On average, same-sex partners were less segregated from different-sex partners in 2010 than in 2000, and the vast majority of same-sex partners lived in environments of declining segregation. Segregation was lower and declined more rapidly in places that had a greater percentage of graduate degree holders. In addition, segregation of female partners was lower in places that had a greater share of female partner households with children. These findings suggest that sexual orientation should be considered alongside economic status, race, and ethnicity as an important factor that contributes to neighborhood differentiation and urban spatial inequality.

  20. Characterization of Sex Determination and Sex Differentiation Genes in Latimeria

    PubMed Central

    Forconi, Mariko; Canapa, Adriana; Barucca, Marco; Biscotti, Maria A.; Capriglione, Teresa; Buonocore, Francesco; Fausto, Anna M.; Makapedua, Daisy M.; Pallavicini, Alberto; Gerdol, Marco; De Moro, Gianluca; Scapigliati, Giuseppe

    2013-01-01

    Genes involved in sex determination and differentiation have been identified in mice, humans, chickens, reptiles, amphibians and teleost fishes. However, little is known of their functional conservation, and it is unclear whether there is a common set of genes shared by all vertebrates. Coelacanths, basal Sarcopterygians and unique “living fossils”, could help establish an inventory of the ancestral genes involved in these important developmental processes and provide insights into their components. In this study 33 genes from the genome of Latimeria chalumnae and from the liver and testis transcriptomes of Latimeria menadoensis, implicated in sex determination and differentiation, were identified and characterized and their expression levels measured. Interesting findings were obtained for GSDF, previously identified only in teleosts and now characterized for the first time in the sarcopterygian lineage; FGF9, which is not found in teleosts; and DMRT1, whose expression in adult gonads has recently been related to maintenance of sexual identity. The gene repertoire and testis-specific gene expression documented in coelacanths demonstrate a greater similarity to modern fishes and point to unexpected changes in the gene regulatory network governing sexual development. PMID:23634199

  1. Sex differences in brain control of prosody.

    PubMed

    Rymarczyk, Krystyna; Grabowska, Anna

    2007-03-14

    Affective (emotional) prosody is a neuropsychological function that encompasses non-verbal aspects of language that are necessary for recognizing and conveying emotions in communication, whereas non-affective (linguistic) prosody indicates whether the sentence is a question, an order or a statement. Considerable evidence points to a dominant role for the right hemisphere in both aspects of prosodic function. However, it has yet to be established whether separate parts of the right hemisphere are involved in processing different kinds of emotional intonation. The aim of this study was to answer this question. In addition, the issue of sex differences in the ability to understand prosody was considered. Fifty-two patients with damage to frontal, temporo-parietal or subcortical (basal) parts of the right hemisphere and 26 controls were tested for their ability to assess prosody information in normal (well-formed) sentences and in pseudo-sentences. General impairment of prosody processing was seen in all patient groups but the effect of damage was more apparent for emotional rather than linguistic prosody. Interestingly, appreciation of emotional prosody appeared to depend on the type of emotional expression and the location of the brain lesion. The patients with frontal damage were mostly impaired in comprehension of happy intonations; those with temporo-parietal damage in assessment of sad intonations, while subcortical lesions mostly affected comprehension of angry intonations. Differential effects of lesion location on the performance of men and women were also observed. Frontal lesions were more detrimental to women, whereas subcortical lesions led to stronger impairment in men. This suggests sex differences in brain organization of prosodic functions. PMID:17005213

  2. Sex education for emotionally disturbed adolescents.

    PubMed

    Schoenholtz, S W; Horowitz, H A; Shtarkshall, R

    1989-02-01

    Under investigation were effects of a course in sex education on a population of emotionally disturbed adolescents who were enrolled as day patients in a school program that is part of the Adolescent Treatment Program of the Institute of Pennsylvania Hospital. Subjects included 7 females, and 8 males, aged 15-18, with severe socio-emotional and educational problems. Pre-and posttesting were used to measure changes. Measures included a short form questionnaire assessing sexual knowledge and attitudes, the Draw-a-Person test, and behavioral observations by teachers, faculty, and Adolescent Treatment Program staff. The results of the study indicated that patients responded age appropriately and gained knowledge and an increased openness about sexuality issues. On the knowledge section of the questionnaire areas addressed in class, such as contraception, were the areas that students showed improvement in student response. The attitudes section revealed an increase in uncertainty about their own values, or conversely, an increase in establishing their values more firmly. In the Draw-a-Person test there was a greater degree of openness and less defensiveness in the posttest drawings. Most postcourse drawings also included more sexual signs and showed nudity. Behavioral changes were noted in the student's increased class contributions and participation, as well as in a more frequent focus of issues relating to sexuality and maturation. In addition, there was no regression or dysfunction as a result of the materials presented, and therapeutic and educational processes were not disrupted by the patient's involvement in the course. It was concluded that a sex education course is clinically and educationally useful on many levels within a therapeutic setting. PMID:12342338

  3. Sex research and social change.

    PubMed

    Gagnon, J H

    1975-03-01

    The history of scientific sex research which emerged at the turn of the century with the exemplary work of Sigmund Freud and Havelock Ellis has been complexly interactive with changing general social conditions, specific trends in sexual conduct, the content of sexual ideologies, and the developing techniques of scientific inquiry. The earliest sex researchers, although serving to bring sexuality out of the Victorian cold and into the center of human development based their views of sexuality on control-repression and drive models. The Freudian tradition was especially influential in general intellectual matters and was probably the most important in the development of twentieth-century sexual ideologies. Beginning in the 1920s and culminating in the work of Kinsey in the 1940s and 1950s, a tradiition of social bookkeeping began focusing on the sexual behavior of relatively normal persons. Methodologically such studies moved away from the case history and from populations who were defined as criminal or neurotic. At the same time, general social changes were occurring that were directly affecting the rates and directions of sexual conduct in the society. The work of Alfred Kinsey charted these changes and in turn influenced public attitudes, public policy, and research interests during the 1950s and 1960s. The work of other researchers began to fill in the picture of sexual conduct in the society from a survey point of view, and some workers began studies in sexual deviance that focused anew on homosexuality and prostitution. The work of William Masters and Virginia Johnson served to open the door to studies of sexual anatomy and physiology by applying well-known techniques to the laboratory study of the sexual. While the biological tradition is still strong in the discussion of the sexual, new emphases are being placed on a cognitive-social learning persepctive that emphasizes the nonbiological factors in sexual development. Major changes have occurred in the

  4. Extramarital sex among Nigerian men: polygyny and other risk factors.

    PubMed

    Mitsunaga, Tisha M; Powell, Antonia M; Heard, Nathan J; Larsen, Ulla M

    2005-08-01

    The AIDS epidemic in Nigeria is generalized, with infection primarily occurring through heterosexual transmission. It is important to understand patterns of sexual behavior to assess their impact on the epidemic and to design appropriate intervention strategies. This study examined risk factors for extramarital sex among Nigerian men, with a particular focus on polygyny and peri- and postpartum abstinence. Data from the 2003 Nigeria Demographic and Health Survey were analyzed for 1153 men and their wives. Eleven percent of men reported extramarital sex in the previous year. Logistic regression models showed that men with 3 or more wives were at the greatest risk for extramarital sex, followed by monogamous men, when compared with men with 2 wives. Other significant predictors included region, religion, wealth, age at sexual debut, and self-perceived risk of HIV infection. Peri- and postpartum abstinence was not significant. Based on these findings, HIV prevention programs should include men with 3 or more wives and those living in the southwest region, in addition to activities targeting men of all ages. Given the heterogeneity within Nigeria, further in-depth studies should be undertaken to explore the relation between number of wives, peri- and postpartum abstinence, and extramarital sex within specific communities.

  5. Sex differences in substance use disorders: focus on side effects.

    PubMed

    Agabio, Roberta; Campesi, Ilaria; Pisanu, Claudia; Gessa, Gian Luigi; Franconi, Flavia

    2016-09-01

    Although sex differences in several aspects of substance use disorders (SUDs) have been identified, less is known about the importance of possible sex differences in side effects induced by substances of abuse or by medications used to treat SUDs. In the SUD field, the perception of certain subjective effects are actively sought, while all other manifestations might operationally be considered side effects. This article was aimed at reviewing sex differences in side effects induced by alcohol, nicotine, heroin, marijuana and cocaine and by medications approved for alcohol, nicotine and heroin use disorders. A large body of evidence suggests that women are at higher risk of alcohol-induced injury, liver disease, cardiomyopathy, myopathy, brain damages and mortality. The risk of tobacco-induced coronary heart disease, lung disease and health problems is higher for women than for men. Women also experience greater exposure to side effects induced by heroin, marijuana and cocaine. In addition, women appear to be more vulnerable to the side effects induced by medications used to treat SUDs. Patients with SUDs should be advised that the risk of developing health problems may be higher for women than for men after consumption of the same amount of substances of abuse. Doses of medications for SUD women should be adjusted at least according to body weight. The sex differences observed also indicate an urgent need to recruit adequate numbers of female subjects in pre-clinical and clinical studies to improve our knowledge about SUDs in women. PMID:27001402

  6. Fetal sex and race modify the predictors of fetal growth.

    PubMed

    Reynolds, Simone A; Roberts, James M; Bodnar, Lisa M; Haggerty, Catherine L; Youk, Ada O; Catov, Janet M

    2015-04-01

    The objective of this study is unknown if fetal sex and race modify the impact of maternal pre-pregnancy body mass index (BMI), and smoking on fetal growth. The authors studied markers of fetal growth in singleton offspring of 8,801 primiparous, normotensive women, enrolled in the Collaborative Perinatal Project. The authors tested for departures from additivity between sex/race and each predictor. The head-to-chest circumference ratio (HCC) decreased more, while birthweight and ponderal index (PI) increased more for each 1 kg/m(2) increase in pre-pregnancy BMI among term females versus males (P = 0.07, P < 0.01 and P = 0.08, interaction respectively). For term offspring of White compared with Black women, smoking independent of "dose" was associated with larger reductions in growth (165 g vs. 68 g reduction in birthweight, P < 0.01, interaction), greater reduction in fetal placental ratio (P < 0.01, interaction), PI (P < 0.01, interaction), and greater increase in HCC (P = 0.02), respectively. The association of BMI and smoking with fetal size appeared to be reversed in term versus preterm infants. Our study provides evidence that the associations of pre-pregnancy BMI and smoking are not constant across sex and race. This finding may be relevant to sex and race differences in neonatal and long term health outcomes. PMID:25030701

  7. Sex differences in substance use disorders: focus on side effects.

    PubMed

    Agabio, Roberta; Campesi, Ilaria; Pisanu, Claudia; Gessa, Gian Luigi; Franconi, Flavia

    2016-09-01

    Although sex differences in several aspects of substance use disorders (SUDs) have been identified, less is known about the importance of possible sex differences in side effects induced by substances of abuse or by medications used to treat SUDs. In the SUD field, the perception of certain subjective effects are actively sought, while all other manifestations might operationally be considered side effects. This article was aimed at reviewing sex differences in side effects induced by alcohol, nicotine, heroin, marijuana and cocaine and by medications approved for alcohol, nicotine and heroin use disorders. A large body of evidence suggests that women are at higher risk of alcohol-induced injury, liver disease, cardiomyopathy, myopathy, brain damages and mortality. The risk of tobacco-induced coronary heart disease, lung disease and health problems is higher for women than for men. Women also experience greater exposure to side effects induced by heroin, marijuana and cocaine. In addition, women appear to be more vulnerable to the side effects induced by medications used to treat SUDs. Patients with SUDs should be advised that the risk of developing health problems may be higher for women than for men after consumption of the same amount of substances of abuse. Doses of medications for SUD women should be adjusted at least according to body weight. The sex differences observed also indicate an urgent need to recruit adequate numbers of female subjects in pre-clinical and clinical studies to improve our knowledge about SUDs in women.

  8. Sex-dependent gene regulatory networks of the heart rhythm

    PubMed Central

    Iacobas, S.; Thomas, N.; Spray, D. C.

    2010-01-01

    Expression level, control, and intercoordination of 66 selected heart rhythm determinant (HRD) genes were compared in atria and ventricles of four male and four female adult mice. We found that genes encoding various adrenergic receptors, ankyrins, ion channels and transporters, connexins, cadherins, plakophilins, and other components of the intercalated discs form a complex network that is chamber dependent and differs between the two sexes. In addition, most HRD genes in atria had higher expression in males than in females, while in ventricles, expression levels were mostly higher in females than in males. Moreover, significant chamber differences were observed between the sexes, with higher expression in atria than ventricles for males and higher expression in ventricles than atria for females. We have ranked the selected genes according to their prominence (new concept) within the HRD gene web defined as extent of expression coordination with the other web genes and stability of expression. Interestingly, the prominence hierarchy was substantially different between the two sexes. Taken together, these findings indicate that the organizational principles of the heart rhythm transcriptome are sex dependent, with the newly introduced prominence analysis allowing identification of genes that are pivotal for the sexual dichotomy. PMID:19756788

  9. Adolescent same-sex and opposite-sex best friend interactions.

    PubMed

    McBride, C K; Field, T

    1997-01-01

    In the present study, 48 high school juniors selected their best same-sex and opposite-sex friends for a videotaping of 10-minute face-to-face interactions together. Females felt more comfortable during same-sex interactions than during opposite-sex interactions, and they rated their same-sex partners more positively than did males. Although second-by-second codings of the videotapes yielded no group differences on the percentage of time the dyads were in interested or animated states, females were in more playful states during their same-sex interactions and males were more playful during their interactions with females.

  10. The X Chromosome of Hemipteran Insects: Conservation, Dosage Compensation and Sex-Biased Expression

    PubMed Central

    Pal, Arka; Vicoso, Beatriz

    2015-01-01

    Insects of the order Hemiptera (true bugs) use a wide range of mechanisms of sex determination, including genetic sex determination, paternal genome elimination, and haplodiploidy. Genetic sex determination, the prevalent mode, is generally controlled by a pair of XY sex chromosomes or by an XX/X0 system, but different configurations that include additional sex chromosomes are also present. Although this diversity of sex determining systems has been extensively studied at the cytogenetic level, only the X chromosome of the model pea aphid Acyrthosiphon pisum has been analyzed at the genomic level, and little is known about X chromosome biology in the rest of the order. In this study, we take advantage of published DNA- and RNA-seq data from three additional Hemiptera species to perform a comparative analysis of the gene content and expression of the X chromosome throughout this clade. We find that, despite showing evidence of dosage compensation, the X chromosomes of these species show female-biased expression, and a deficit of male-biased genes, in direct contrast to the pea aphid X. We further detect an excess of shared gene content between these very distant species, suggesting that despite the diversity of sex determining systems, the same chromosomal element is used as the X throughout a large portion of the order. PMID:26556591

  11. Review: Male systemic lupus erythematosus: a review of sex disparities in this disease.

    PubMed

    Lu, L-J; Wallace, D J; Ishimori, M L; Scofield, R H; Weisman, M H

    2010-02-01

    Although males with systemic lupus erythematosus (SLE) represent 4-22% of all SLE patients, it may not be appropriate that these cases should be subordinated to females with SLE in terms of most health-related issues. Over the past few decades, some distinctive features of male lupus have been observed with regard to genetic and environmental aspects of sex differences, clinical features, and outcome. In addition, recent insights into sex disparities in this disease have brought forth a few plausible and novel pathogenetic hypotheses. This review discusses these findings and sex disparities in SLE that appear to be especially noteworthy and pertinent to our understanding of male SLE.

  12. Sex steroids and growth hormone interactions.

    PubMed

    Fernández-Pérez, Leandro; de Mirecki-Garrido, Mercedes; Guerra, Borja; Díaz, Mario; Díaz-Chico, Juan Carlos

    2016-04-01

    GH and sex hormones are critical regulators of body growth and composition, somatic development, intermediate metabolism, and sexual dimorphism. Deficiencies in GH- or sex hormone-dependent signaling and the influence of sex hormones on GH biology may have a dramatic impact on liver physiology during somatic development and in adulthood. Effects of sex hormones on the liver may be direct, through hepatic receptors, or indirect by modulating endocrine, metabolic, and gender-differentiated functions of GH. Sex hormones can modulate GH actions by acting centrally, regulating pituitary GH secretion, and peripherally, by modulating GH signaling pathways. The endocrine and/or metabolic consequences of long-term exposure to sex hormone-related compounds and their influence on the GH-liver axis are largely unknown. A better understanding of these interactions in physiological and pathological states will contribute to preserve health and to improve clinical management of patients with growth, developmental, and metabolic disorders.

  13. Determinants of extramarital sex in the Philippines.

    PubMed

    Ahlburg, D A; Jensen, E R; Perez, A E

    1997-01-01

    Understanding the factors associated with sexual behaviour is critical in slowing the spread of HIV in the Philippines, where sexual transmission accounts for most HIV infections, with the majority from heterosexual activity. Further, unprotected sex is common, as is sex with prostitutes. These factors increase the risks associated with extramarital sex. From an analysis of a nationally representative sample of women, we found that a number of factors were related to women's reports of their husbands' sexual activity outside their current relationship: women report that partners who are more educated, have been in the current relationship longer, and who had sex before marriage are more likely to be engaging in sex outside the marriage. Further, men who are older, who are farmers, who live at home, and who have more educated wives, were believed to be less likely to be having extramarital sex.

  14. Sex differences and stress across the lifespan

    PubMed Central

    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

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

    PubMed

    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.

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

    PubMed

    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. PMID:27383844

  17. Interactive effects of culture and sex hormones on the sex role self-concept

    PubMed Central

    Pletzer, Belinda; Petasis, Ourania; Ortner, Tuulia M.; Cahill, Larry

    2015-01-01

    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. PMID:26236181

  18. Interactive effects of culture and sex hormones on the sex role self-concept.

    PubMed

    Pletzer, Belinda; Petasis, Ourania; Ortner, Tuulia M; Cahill, Larry

    2015-01-01

    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.

  19. A snail with unbiased population sex ratios but highly biased brood sex ratios.

    PubMed Central

    Yusa, Yoichi; Suzuki, Yoshito

    2003-01-01

    Extraordinary sex ratio patterns and the underlying sex-determining mechanisms in various organisms are worth investigating, particularly because they shed light on adaptive sex-ratio adjustment. Here, we report an extremely large variation in the brood sex ratio in the freshwater snail, Pomacea canaliculata. In eight rearing series originating from three wild populations, sex ratios were highly variable among broods, ranging continuously from almost exclusively males to almost exclusively females. However, sex ratios were similar between broods from the same mating pair, indicating that sex ratio is a family trait. Irrespective of the large variations, the average sex ratios in all rearing series were not significantly different from 0.5. We argue that Fisher's adaptive sex-ratio theory can explain the equal average sex ratios, and the results, in turn, directly support Fisher's theory. Polyfactorial sex determination (in which sex is determined by three or more genetic factors) is suggested as the most likely mechanism producing the variable brood sex ratio. PMID:12614578

  20. [Sex "addiction": compulsion and controversy].

    PubMed

    Souza y Machorro, Mario

    2002-10-01

    Modern occidental society often distorts and, in some cases, ignores healthy concepts regarding sexuality. Besides, It not always considers this, to be mental health or to represent an expression of whole health. Such ambivalence towards sex and the sexual is located between the limits of the sacred and erotic, both associated to taboos and their transgression. Since the last century, the current "neosexual" revolution intents to dismantle old patterns in favor of the dissociation of human sexual sphere, the dispersion of sexual fragments towards individualism and intimate relationships diversification. Within such context, "addiction" to sex and the sexual, as a compulsive conduct, represents on one side a clinical reality each time better observed and diagnosed, where the importance of family history is recognized, as well as individual psychopathology, and marital life, in its etiology and also for its treatment and prevention. On the other hand, it has not been classified in the mental health catalogues as it is not considered, meanwhile, as the problem is been maintained, the co-morbidity and its consequences multiply, and the controversy continues.

  1. Sex hormones and brain aging.

    PubMed

    Veiga, Sergio; Melcangi, Roberto C; Doncarlos, Lydia L; Garcia-Segura, Luis M; Azcoitia, Iñigo

    2004-01-01

    Sex steroids exert pleiotropic effects in the nervous system, preserving neural function and promoting neuronal survival. Therefore, the age-related decrease in sex steroids may have a negative impact on neural function. Progesterone, testosterone and estradiol prevent neuronal loss in the central nervous system in different experimental animal models of neurodegeneration. Furthermore, progesterone and its reduced derivatives dihydroprogesterone and tetrahydroprogesterone reduce aging-associated morphological abnormalities of myelin and aging-associated myelin fiber loss in rat peripheral nerves. However, the results from hormone replacement studies in humans are thus far inconclusive. A possible alternative to hormonal replacement therapy is to increase local steroidogenesis by neural tissues, which express enzymes for steroid synthesis and metabolism. Proteins involved in the intramitochondrial trafficking of cholesterol, the first step in steroidogenesis, such as the peripheral-type benzodiazepine receptor and the steroidogenic acute regulatory protein, are up-regulated in the nervous system after injury. Furthermore, steroidogenic acute regulatory protein expression is increased in the brain of 24-month-old rats compared with young adult rats. This suggests that brain steroidogenesis may be modified in adaptation to neurodegenerative conditions and to the brain aging process. Furthermore, recent studies have shown that local formation of estradiol in the brain, by the enzyme aromatase, is neuroprotective. Therefore, steroidogenic acute regulatory protein, peripheral-type benzodiazepine receptor and aromatase are attractive pharmacological targets to promote neuroprotection in the aged brain. PMID:15582278

  2. Teens need comprehensive sex education.

    PubMed

    1988-01-01

    Family planning programs throughout the world are making attempts to combat the confusion and ignorance about reproductive health, fertility and contraception among young people. Sex education is becoming part of the curriculum in Asian, Latin American, and Caribbean countries, and some African schools. In Indonesia and other countries educational programs now target parents and young men. Sweden's 1977 program is credited with helping reduce adolescent fertility by 50% and abortion by 25% between 1975 and 1983. In developing countries the emphasis is on outreach efforts. Sri Lanka has population and development projects and Mexico City and Guatemala City offer medical services, counseling, vocational courses and social and cultural activities, as well as sex education and family planning services for young men and women. Family planning groups are also learning to use the media to educate teens. Songs about postponing sexual relations were popularized by the media in Latin America and Caribbean countries, and a commercial film showing the potential disastrous consequences of sexual intercourse was produced in Zimbabwe.

  3. Sex worker health: San Francisco style

    PubMed Central

    Cohan, D; Lutnick, A; Davidson, P; Cloniger, C; Herlyn, A; Breyer, J; Cobaugh, C; Wilson, D; Klausner, J

    2006-01-01

    Objectives To describe the characteristics of sex workers accessing care at a peer based clinic in San Francisco and to evaluate predictors of sexually transmitted infections (STI). Methods We conducted an observational study of sex workers at St James Infirmary. Individuals underwent an initial questionnaire, and we offered screening for STI at each clinic visit. We performed univariate, bivariate, and multivariable analyses to assess for predictors of STI in this population. Results We saw 783 sex workers identifying as female (53.6%), male (23.9%), male to female transgender (16.1%), and other (6.5%). 70% had never disclosed their sex work to a medical provider. Participants represented a wide range of ethnicities, educational backgrounds, and types of sex work. The most common substance used was tobacco (45.8%). Nearly 40% reported current illicit drug use. Over half reported domestic violence, and 36.0% reported sex work related violence. Those screened had gonorrhoea (12.4%), chlamydia (6.8%), syphilis (1.8%), or herpes simplex virus 2 (34.3%). Predictors of STI included African‐American race (odds ratio (OR) 3.3), male gender (OR 1.9), and sex work related violence (OR 1.9). In contrast, participants who had only ever engaged in collective sex work were less likely to have an STI (OR 0.4). Conclusions The majority of sex workers have never discussed their work with a medical provider. Domestic violence is extremely prevalent as is work related violence. Working with other sex workers appears to be protective of STIs. STI prevention interventions should target African‐American and male sex workers. Addressing violence in the workplace and encouraging sex workers to work collectively may be effective prevention strategies. PMID:16854996

  4. Sex determination in forensic odontology: A review.

    PubMed

    Ramakrishnan, K; Sharma, Subramanya; Sreeja, C; Pratima, D Bhavani; Aesha, I; Vijayabanu, B

    2015-08-01

    Forensic odontology is the application of dental principles to legal issues. Sex determination is a subdivision of forensic odontology and it is very important especially when information relating to the deceased is unavailable. Sex determination becomes the first priority in the process of identification of a person by a forensic investigator in the case of mishaps, chemical and nuclear bomb explosions, natural disasters crime investigations, and ethnic studies. This article reviews upon the various methods used in sex determination. PMID:26538886

  5. Genomic Architecture of Asthma Differs by Sex

    PubMed Central

    Mersha, Tesfaye B.; Martin, Lisa J.; Myers, Jocelyn M. Biagini; Kovacic, Melinda Butsch; He, Hua; Lindsey, Mark; Sivaprasad, Umasundari; Chen, Weiguo; Hershey, Gurjit K. Khurana

    2015-01-01

    Asthma comprised of highly heterogeneous subphenotypes resulting from complex interplay between genetic and environmental stimuli. While much focus has been placed on extrinsic environmental stimuli, intrinsic environment such as sex can interact with genes to influence asthma risk. However, few studies have examined sex-specific genetic effects. The overall objective of this study was to evaluate if sex-based differences exist in genomic associations with asthma. We tested 411 asthmatics and 297 controls for presence of interactions and sex-stratified effects in 51 genes using both SNP and gene expression data. Logistic regression was used to test for association. Over half (55%) of the genetic variants identified in sex-specific analyses were not identified in the sex-combined analysis. Further, sex-stratified genetic analyses identified associations with significantly higher median effect sizes than sex-combined analysis for girls (p-value =6.5E-15) and for boys (p-value =1.0E-7). When gene expression data was analyzed to identify genes that were differentially expressed in asthma versus non-asthma, nearly one third (31%) of the probes identified in the sex-specific analyses were not identified in the sex-combined analysis. Both genetic and gene expression data suggest that the biologic underpinnings for asthma may differ by sex. Failure to recognize sex interactions in asthma greatly decreases the ability to detect significant genomic variation and may result in significant misrepresentation of genes and pathways important in asthma in different environments. PMID:25817197

  6. Sex determination in forensic odontology: A review

    PubMed Central

    Ramakrishnan, K.; Sharma, Subramanya; Sreeja, C.; Pratima, D. Bhavani; Aesha, I.; Vijayabanu, B.

    2015-01-01

    Forensic odontology is the application of dental principles to legal issues. Sex determination is a subdivision of forensic odontology and it is very important especially when information relating to the deceased is unavailable. Sex determination becomes the first priority in the process of identification of a person by a forensic investigator in the case of mishaps, chemical and nuclear bomb explosions, natural disasters crime investigations, and ethnic studies. This article reviews upon the various methods used in sex determination. PMID:26538886

  7. Male sex drive and the maintenance of sex: evidence from Drosophila.

    PubMed

    Singh, Rama S; Artieri, Carlo G

    2010-01-01

    The resolution of the paradoxes surrounding the evolutionary origins and maintenance of sexual reproduction has been a major focus in biology. The operation of sexual selection-which is very common among multicellular organisms-has been proposed as an important factor in the maintenance of sex, though in order for this hypothesis to hold, the strength of sexual selection must be stronger in males than in females. Sexual selection poses its own series of evolutionary questions, including how genetic variability is maintained in the face of sustained directional selection (known as the "paradox of the lek"). In this short review, we present evidence obtained from recent comparative genomics projects arguing that 1) the genomic consequences of sexual selection clearly show that its effect is stronger in males and 2) this sustained selection over evolutionary timescales also has an effect of capturing de novo genes and expression patterns influencing male fitness, thus providing a mechanism via which new genetic variation can be input into to male traits. Furthermore, we argue that this latter process of genomic "masculinization" has an additional effect of making males difficult to purge from populations, as evidence from Drosophila indicates that, for example, many male sexually selected seminal fluid factors are required to ensure maximally efficient reproduction. Newly arising parthenogenic mutations would suffer an immediate reproductive rate disadvantage were these proteins lost. We show that recent studies confirm that genomic masculinization, as a result of "male sex drive," has important consequences for the evolution of sexually dimorphic species.

  8. Tracing back the nascence of a new sex-determination pathway to the ancestor of bees and ants.

    PubMed

    Schmieder, Sandra; Colinet, Dominique; Poirié, Marylène

    2012-06-12

    In several Hymenoptera, sexual fate is determined by the allelic composition at the complementary sex-determiner locus, a sex-determination mechanism that can strongly affect population dynamics. To date, the molecular identification of complementary sex determiner has only been achieved in the honeybee, where the complementary sex-determiner gene was reported to have arisen from duplication of the feminizer gene. Strikingly, the complementary sex-determiner gene was also proposed to be unique to the honeybee lineage. Here we identify feminizer and complementary sex-determiner orthologues in bumble bees and ants. We further demonstrate that the duplication of feminizer that produced complementary sex determiner occurred before the divergence of Aculeata species (~120 Myr ago). Finally, we provide evidence that the two genes evolved concertedly through gene conversion, complementary sex-determiner evolution being additionally shaped by mosaic patterns of selection. Thus, the complementary sex-determiner gene likely represents the molecular basis for single locus-complementary sex determination in the Aculeata infra-order, and possibly, in the entire Hymenoptera order.

  9. On the variability of alligator sex ratios

    USGS Publications Warehouse

    Nichols, J.D.; Chabreck, R.H.

    1980-01-01

    Samples of alligators from wild and 'farm' populations exhibited disproportionate sex ratios. Males predominated among young alligators from wild populations, whereas females were much more abundant than males in the farm population, where resources were superabundant. These results and other considerations lead us to hypothesize that environmental factors influence sex determination in alligators. During favorable environmental conditions natural selection is expected to favor a preponderance of the sex whose individuals exhibit the greater environmentally associated variation in relative fitness. We hypothesize that environmentally associated variation in age at sexual maturity of females produces sufficient variation in relative fitness of females to result in selection for low sex ratios during periods of resource abundance.

  10. Economic analysis of same-sex marriage.

    PubMed

    Portelli, Christopher J

    2004-01-01

    This article applies the neoclassical microeconomic analysis of marriage as developed by Nobel laureate economist Gary Becker to same-sex marriage. The objective is to demonstrate that the economic analysis of marriage supports allowing same-sex marriage, and that same-sex marriages would strengthen the incentive to marry, increase the efficiency of marriage markets, provide for more children to be raised in two-parent optimum environments, and benefit states economically overall. The article concludes with an overview of the economic impact of same-sex marriages on states based on the analysis, data and fiscal information currently available from researchers and economists in the field.

  11. The evolution of sex differences in disease.

    PubMed

    Morrow, Edward H

    2015-01-01

    It is now becoming widely recognized that there are important sex differences in disease. These include rates of disease incidence, symptoms and age of onset. These differences between the sexes can be seen as a subset of the more general phenomenon of sexual dimorphism of quantitative phenotypes. From a genetic point of view, this is paradoxical, since the vast majority of genetic material is shared between the sexes. How can males and females differ in so many ways and yet have a common genetic code? Traditionally, the modifying action of hormones has been offered as a solution to this paradox, but experiments disentangling the effects of hormones and sex-chromosomes have shown that this cannot be the sole explanation. In this review, I outline current ideas about the evolutionary origins of sex differences in phenotypes, with a particular focus on how sex differences in disease can arise. I also discuss how sex differences in themselves can generate new risk factors for disease, in effect becoming a new environmental factor, as well as briefly reviewing more general evidence for sexually antagonistic selection and genetic variation within humans. Taking an evolutionary view on sex differences in disease provides an opportunity for greater understanding of mechanisms of disease and as such provides a clear motivation for clinicians to explore how therapies may be tailored to the individual in a sex-dependent way.

  12. Economic analysis of same-sex marriage.

    PubMed

    Portelli, Christopher J

    2004-01-01

    This article applies the neoclassical microeconomic analysis of marriage as developed by Nobel laureate economist Gary Becker to same-sex marriage. The objective is to demonstrate that the economic analysis of marriage supports allowing same-sex marriage, and that same-sex marriages would strengthen the incentive to marry, increase the efficiency of marriage markets, provide for more children to be raised in two-parent optimum environments, and benefit states economically overall. The article concludes with an overview of the economic impact of same-sex marriages on states based on the analysis, data and fiscal information currently available from researchers and economists in the field. PMID:15189788

  13. Canadian tourist and Dominican Republic sex workers.

    PubMed

    Herold, E S

    1992-01-01

    The Dominican Republic is a popular tourist destination for Canadians. The country's sex industry for tourists developed markedly in the 1980s. The Puerto Plata/Sosua area is currently one of the most popular tourist sites and claimed the highest incidence of AIDS in 1989 at 23.2 cases/100,000 people. Two pilot phases of the Dominican Sex Workers and Canadian Tourists Study have been conducted to obtain methodological and empirical data to use in developing a major study of sex and tourism. First phase interviews were held only with beachboys who make money by having relations with female tourists, while phase two interviews were held with beachboys, female sex workers, and female and male tourists. Results indicate that female tourists consider their relations with male sex workers to be primarily social, while male tourists see their relations with female sex workers as more casual, sexual, and monetarily based. Further, women are more likely than men to continue their relationships with sex workers after returning to Canada; many help their men to immigrate and some get married. To learn more about the dynamics of tourism, sex, and AIDS prevention, the author proposes individual studies exploring the characteristics of each of the following four populations: male and female sex workers and male and female tourists.

  14. Update on sexed semen technology in cattle.

    PubMed

    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%. PMID:24680061

  15. Evolutionary stability of sex chromosomes in snakes.

    PubMed

    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.

  16. Towards a more nuanced understanding of the relationship between sex-biased gene expression and rates of protein-coding sequence evolution.

    PubMed

    Meisel, Richard P

    2011-06-01

    Genes that are differentially expressed between the sexes (sex-biased genes) are among the fastest evolving genes in animal genomes. The majority of sex-biased expression is attributable to genes that are primarily expressed in sex-limited reproductive tissues, and these reproductive genes are often rapidly evolving because of intra- and intersexual selection pressures. Additionally, studies of multiple taxa have revealed that genes with sex-biased expression are also expressed in a limited number of tissues. This is worth noting because narrowly expressed genes are known to evolve faster than broadly expressed genes. Therefore, it is not clear whether sex-biased genes are rapidly evolving because they have sexually dimorphic expression, because they are expressed in sex-limited reproductive tissues, or because they are narrowly expressed. To determine the extend to which other confounding variables can explain the rapid evolution of sex-biased genes, I analyzed the rates of evolution of sex-biased genes in Drosophila melanogaster and Mus musculus in light of tissue-specific measures of expression. I find that genes with sex-biased expression in somatic tissues shared by both sexes are often evolving faster than non-sex-biased genes, but this is best explained by the narrow expression profiles of sex-biased genes. Sex-biased genes in sex-limited tissues in D. melanogaster, however, evolve faster than other narrowly expressed genes. Therefore, the rapid evolution of sex-biased genes is limited only to those genes primarily expressed in sex-limited reproductive tissues.

  17. Control of mammalian sex ratio by sexing sperm

    SciTech Connect

    Gledhill, B.L.

    1983-11-01

    Preselection of sex is discussed with emphasis on methods which have claimed success in separating X- and Y-chromosome-bearing sperm. Much of the recent experimental work in separating human X and Y sperm judges the success of enrichment solely by staining for the Y sperm with a quinacrine dye, which causes a bright fluorescence of the long arm of the Y chromosome. This method is questioned because the endpoint may be producing spurious results. Flow sorting is believed to be the first verified separation of mammalian sperm, but the sperm were nonviable. Flow cytometry can be used to quickly determine the success of other enrichment techniques. Bulk separation, as contrasted to separation based on determination of individual sperm characteristics, with 80% enrichment seems to be a reasonable future goal.

  18. Sex hormones adjust "sex-specific" reactive and diurnal cortisol profiles.

    PubMed

    Juster, Robert-Paul; Raymond, Catherine; Desrochers, Alexandra Bisson; Bourdon, Olivier; Durand, Nadia; Wan, Nathalie; Pruessner, Jens C; Lupien, Sonia J

    2016-01-01

    Sex differences in stress hormone functions are presumed to depend on sex hormones. And yet, surprisingly few psychoneuroendocrine studies actually assess within-sex variations of testosterone, estradiol, and progesterone when investigating sex-specific activities of the hypothalamic-pituitary-adrenal axis. In this methodological study of 204 healthy adults (60 men), we assessed whether cortisol profiles would differ between the sexes when unadjusted or adjusted for basal sex hormones among both sexes. Reactive cortisol was sampled using 6 saliva samples measured every 10-min as part of the Trier Social Stress Test that generally activates cortisol among men more than women. Diurnal cortisol was sampled over two days at (1) awakening, (2) 30-min thereafter, (3) 1400 h, (4) 1600 h, and (5) bedtime. Sex hormones were collected at baseline before the psychosocial stressor and on two occasions during diurnal cortisol assessment. Repeated-measures analysis of covariance controlled for key covariates in analyses unadjusted or adjusted for sex hormones. Results revealed that men had higher reactive cortisol than women in unadjusted analysis, but this sex difference was attenuated when adjusting for sex hormones. While diurnal cortisol showed no sex differences in unadjusted models, adjusting for sex hormones revealed that women have higher morning cortisol. Correlations using area under the curve formulae revealed intriguing sex-specific associations with progesterone in men and testosterone in women that we propose have implications for social and affective neuroscience. In summary, our results reveal that adjusting for sex hormones alters "sex-specific" reactive and diurnal cortisol profiles.

  19. Female sex and obesity increase photophobic behavior in mice.

    PubMed

    Rossi, Heather L; Lara, Orlando; Recober, Ana

    2016-09-01

    Migraine affects predominantly women. Furthermore, epidemiological studies suggest that obesity is a risk factor for migraine and this association is influenced by sex. However, the biological basis for this bias is unclear. To address this issue, we assessed light avoidant behavior, a surrogate of photophobia, in female C57BL/6J mice fed regular diet (RD) or high-fat diet (HFD, 60% kcal from fat). We first assessed sex differences in basal photophobia in 20-25-week-old mice and found that both obese and lean females spent significantly less time in light than their male counterparts. Next, we assessed photophobia evoked by trigeminal stimulation with intradermal capsaicin. Females at 20-25weeks of age did not display capsaicin-evoked photophobic behavior unless they had diet-induced obesity. When we tested 8-11-week-old females to determine if the diet alone could be responsible for this effect, we found that both HFD and RD 8-11-week-old females exhibit capsaicin-evoked photophobic behavior. This is in contrast to what we have previously shown in males and indicates a sex difference in the photophobic behavior of mice. Comparison of 20-25-week-old RD mice with 8-11-week-old RD mice suggests that age or age-related weight gain may contribute to capsaicin-evoked photophobic behavior in males, but not in females. These findings suggest that obesity exacerbates photophobia in both sexes, but additional work is needed to understand the sex- and age-specific mechanisms that may contribute to photophobia and trigeminal pain. PMID:27328418

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

    ERIC Educational Resources Information Center

    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)

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

    ERIC Educational Resources Information Center

    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…

  2. Differences and Consistency between Same-Sex and Other-Sex Peer Relationships during Early Adolescence.

    ERIC Educational Resources Information Center

    Bukowski, William M.; And Others

    1993-01-01

    Found that individual differences in children's preference for same-sex peers were (1) derived from liking same-sex peers rather than disliking other-sex peers; (2) consistent over long intervals; and (3) related to children's preference for activities that required gross motor skills. (BC)

  3. Same-Sex Patterns and Sex Differences in the Trust-Value Basis of Children's Friendship.

    ERIC Educational Resources Information Center

    Rotenberg, Ken J.

    1986-01-01

    A sample of grade four students reported the secret-sharing and promise-making behavior of classroom peers and judged those classmates on trust and friendship. Findings suggest that the same-sex friendship patterns are maintained by same-sex trust patterns through infrequent secret-sharing with opposite-sex peers and the perception that…

  4. Birth cohort and the specialization gap between same-sex and different-sex couples.

    PubMed

    Giddings, Lisa; Nunley, John M; Schneebaum, Alyssa; Zietz, Joachim

    2014-04-01

    We examine differences in household specialization between same-sex and different-sex couples within and across three birth cohorts: Baby Boomers, Generation X, and Generation Y. Using three measures of household specialization, we find that same-sex couples are less likely than their different-sex counterparts to exhibit a high degree of specialization. However, the "specialization gap" between same-sex and different-sex couples narrows across birth cohorts. These findings are indicative of a cohort effect. Our results are largely robust to the inclusion of a control for the presence of children and for subsets of couples with and without children. We provide three potential explanations for why the specialization gap narrows across cohorts. First, different-sex couples from more recent birth cohorts may have become more like same-sex couples in terms of household specialization. Second, social and legal changes may have prompted a greater degree of specialization within same-sex couples relative to different-sex couples. Last, the advent of reproductive technologies, which made having children easier for same-sex couples from more recent birth cohorts, could result in more specialization in such couples relative to different-sex couples. PMID:24585040

  5. The Effects of Equal Status Cross-Sex Contact on Students' Sex Stereotyped Attitudes and Behavior.

    ERIC Educational Resources Information Center

    Lockheed, Marlaine E.; Harris, Abigail M.

    Standard least squares regression techniques are used to estimate the effects of non-sex-role stereotypes, equal-status cross-sex interaction and female leadership on changes in children's sex stereotyped attitudes. Included are a pretest, experimental treatment, and post-test. Teachers of approximately 400 fourth and fifth grade children received…

  6. Birth cohort and the specialization gap between same-sex and different-sex couples.

    PubMed

    Giddings, Lisa; Nunley, John M; Schneebaum, Alyssa; Zietz, Joachim

    2014-04-01

    We examine differences in household specialization between same-sex and different-sex couples within and across three birth cohorts: Baby Boomers, Generation X, and Generation Y. Using three measures of household specialization, we find that same-sex couples are less likely than their different-sex counterparts to exhibit a high degree of specialization. However, the "specialization gap" between same-sex and different-sex couples narrows across birth cohorts. These findings are indicative of a cohort effect. Our results are largely robust to the inclusion of a control for the presence of children and for subsets of couples with and without children. We provide three potential explanations for why the specialization gap narrows across cohorts. First, different-sex couples from more recent birth cohorts may have become more like same-sex couples in terms of household specialization. Second, social and legal changes may have prompted a greater degree of specialization within same-sex couples relative to different-sex couples. Last, the advent of reproductive technologies, which made having children easier for same-sex couples from more recent birth cohorts, could result in more specialization in such couples relative to different-sex couples.

  7. Biological Sex, Sex-Role, and Self-Actualization of College Students.

    ERIC Educational Resources Information Center

    Guyot, Gary W.; Vollemaere, Erik

    Self-actualization, which involves the ultimate development of one's abilities regardless of external influences, is the basis for many personality theories. To assess the relationship between biological sex, sex role, and self-actualization, the Bem Sex Role Inventory (BSRI) and the Personal Orientation Inventory (POI) were administered to 129…

  8. Race and Sex Differences in Sex Role Attitudes of Southern College Students.

    ERIC Educational Resources Information Center

    Lyson, Thomas A.

    1986-01-01

    Investigated race and sex differences in sex role attitudes of southern college students (N=5,750). Black and white men shared similar sex role orientation; black and white women shared a similar world view. Blacks were more likely than whites to feel that woman's real fulfillment comes from motherhood and that it was appropriate for mothers with…

  9. Occupational Achievement Motivation as a Function of Biological Sex, Sex-Linked Personality, and Occupation Stereotype.

    ERIC Educational Resources Information Center

    Garland, Howard; Smith, Gail Berwick

    1981-01-01

    Examined predicted sex differences in occupational achievement motivation. Significant sex by occupation stereotype interactions were found supporting the prediction of highest achievement motivation toward sex appropriate occupations. Females did not show significantly lower motivation toward high prestige masculine occupations--inconsistent with…

  10. Geographic segregation and evidence of density-dependent changes in sex ratios in an abundant colonial waterbird.

    PubMed

    Dorr, Brian S; Hanson-Dorr, Katie C; DeVault, Travis L; Guillaumet, Alban; Barras, Scott C

    2014-11-01

    Demographic information, such as geographic segregation of sexes and sex ratio data, is needed to develop, model and evaluate conservation and management strategies for wildlife. A variety of physiological, behavioral and environmental factors can influence segregation of sexes and sex ratios, many of which originate with density-dependent processes. Departure from 50:50 sex ratios of double-crested cormorants (Phalacrocorax auritus) collected during control efforts in breeding and wintering areas across their eastern range of the USA were evaluated using using a Z-test as well as Stouffer's weighted Z-tests. In addition, a specifically-designed randomization test was used to evaluate density-dependent effects on primary sex ratios in cormorants from egg collections and colony nest count data over a 21-year period. Cormorants collected from breeding colonies were strongly male-biased, whereas cormorants collected from feeding flocks were slightly biased toward females. Cormorants were partly segregated by sex on the wintering grounds, with significantly more males found in areas with intensive channel catfish aquaculture. The null hypothesis that females produced a balanced sex ratio independent of number of nesting cormorants was rejected: more male embryos were produced during rapid population growth, whereas at maximum nesting number more female embryos were produced. Once populations stabilized, the sex ratio was more equal. This examination of sex ratios indicates that different management methods and locations result in sex-biased culling of cormorants. Sex-biased culling in cormorants could make population reduction efforts more efficient and reduce overall take. We suggest further research to examine density-dependent effects on primary sex ratios documented here.

  11. Female sex work and international sport events - no major changes in demand or supply of paid sex during the 2010 Soccer World Cup: a cross-sectional study

    PubMed Central

    2012-01-01

    Background Important unanswered questions remain on the impact of international sporting events on the sex industry. Speculation about increased demand and supply of sex work often generates significant attention, but also additional funding for HIV programmes. This study assessed whether changes occurred in the demand and supply of paid sex during the 2010 Soccer World Cup in South Africa. Methods Trained sex worker interviewers conducted face-to-face semi-structured interviews among consenting female sex workers during May-September 2010. Using bivariate analyses we compared supply, demand, sexual risk-taking, and police and health services contact pre-World Cup, to levels during the World Cup and after the event. Results No increases were detected in indicators of sex work supply, including the proportion of sex workers newly arrived in the city (< 2.5% in each phase) or those recently entering the trade (≤ 1.5%). Similarly, demand for sex work, indicated by median number of clients (around 12 per week) and amount charged per transaction ($13) remained similar in the three study periods. Only a third of participants reported observing any change in the sex industry ascribed to the World Cup. Self-reported condom-use with clients remained high across all samples (> 92.4% in all phases). Health-care utilisation decreased non-significantly from the pre- to during World Cup period (62.4% to 57.0%; P = 0.075). Across all periods, about thirty percent of participants had interacted with police in the preceding month, two thirds of whom had negative interactions. Conclusions Contrary to public opinion, no major increases were detected in the demand or supply of paid sex during the World Cup. Although the study design employed was unable to select population-based samples, these findings do not support the public concern and media speculation prior to the event, but rather signal a missed opportunity for public health action. Given the media attention on sex work

  12. Flow cytometric sexing of mammalian sperm.

    PubMed

    Garner, Duane L

    2006-03-15

    This review reexamines parameters needed for optimization of flow cytometric sexing mammalian sperm and updates the current status of sperm sexing for various species where this technology is currently being applied. Differences in DNA content have provided both a method to differentiate between these sex-determining gametes and a method to sort them that can be used for predetermining sex in mammals. Although the DNA content of all cells for each mammalian species is highly conserved, slight but measurable DNA content differences of sperm occur within species even among cattle breeds due to different sizes of Y-chromosomes. Most mammals produce flattened, oval-headed sperm that can be oriented within a sorter using hydrodynamic forces. Multiplying the percentage the difference in DNA content of the X- or Y-chromosome bearing sperm times the area of the flat profile of the sperm head gives a simple sorting index that suggests that bull and boar sperm are well suited for separation in a flow sorter. Successful sperm sexing of various species must take into account the relative susceptibilities of gametes to the stresses that occur during sexing. Sorting conditions must be optimized for each species to achieve acceptable sperm sexing efficiency, usually at 90% accuracy. In the commercial application of sperm sexing to cattle, fertility of sex-sorted bull sperm at 2 x 10(6)/dose remains at 70-80% of unsexed sperm at normal doses of 10 to 20 x 10(6) sperm. DNA content measurements have been used to identify the sex-chromosome bearing sperm populations with good accuracy in semen from at least 23 mammalian species, and normal-appearing offspring have been produced from sexed sperm of at least seven species. PMID:16242764

  13. Molecular Sex Differences in Human Serum

    PubMed Central

    Ramsey, Jordan M.; Schwarz, Emanuel; Guest, Paul C.; van Beveren, Nico J. M.; Leweke, F. Markus; Rothermundt, Matthias; Bogerts, Bernhard; Steiner, Johann; Ruta, Liliana; Baron-Cohen, Simon; Bahn, Sabine

    2012-01-01

    Background 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. Methodology/Principal Findings 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. Conclusions/Significance 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

  14. METHODS OF PROMOTING SAFER SEX BEHAVIORS UTILIZED BY MEN WHO HAVE SEX WITH MALE CASUAL SEX PARTNERS

    PubMed Central

    Serovich, Julianne M.; Craft, Shonda M.; McDowell, Tiffany L.; Grafsky, Erika L.; Andrist, David

    2009-01-01

    The purpose of this article is to report results of a qualitative investigation into the methods that HIV-positive men who have sex with men (MSM) use to initiate safer sex with casual sexual partners. In-depth, qualitative interviews were conducted with 57 HIV-positive adult MSM living in a large midwestern city. Using an inductive approach to data analysis, participants revealed a typology of safer sex strategies that can be placed into four primary categorizations: having a nonnegotiable sexual behavior policy, behaviorally controlling the interaction, being verbally direct, and being verbally indirect. Strategies varied by degree of explicitness and partner involvement. Men in this study often employed multiple strategies if their partner was not initially receptive to engaging in safer sex behaviors. The strategies described can be especially beneficial to those working in the area of HIV prevention. Providing MSM a variety of options to initiate safer sex may enhance current prevention efforts. PMID:19243227

  15. Sex differences in approaching friends with benefits relationships.

    PubMed

    Lehmiller, Justin J; VanderDrift, Laura E; Kelly, Janice R

    2011-03-01

    This research explored differences in how men and women approach "friends with benefits" (FWB) relationships. Specifically, this study examined sex differences in reasons for beginning such involvements, commitment to the friendship versus sexual aspects of the relationship, and partners'; anticipated hopes for the future. To do so, an Internet sample of individuals currently involved in FWB relationships was recruited. Results indicated many overall similarities in terms of how the sexes approach FWB relationships, but several important differences emerged. For example, sex was a more common motivation for men to begin such relationships, whereas emotional connection was a more common motivation for women. In addition, men were more likely to hope that the relationship stays the same over time, whereas women expressed more desire for change into either a full-fledged romance or a basic friendship. Unexpectedly, both men and women were more committed to the friendship than to the sexual aspect of the relationship. Although some additional similarities appeared, the findings were largely consistent with the notion that traditional gender role expectations and the sexual double standard may influence how men and women approach FWB relationships. PMID:20336576

  16. The evolutionary biology of sex.

    PubMed

    Charlesworth, Brian

    2006-09-01

    In 1861, Charles Darwin wrote "We do not even in the least know the final cause of sexuality; why new beings should be produced by the union of the two sexual elements, instead of by a process of parthenogenesis". It was hardly possible to begin to answer this question at that time, in view of the contemporary lack of knowledge of genetics and cell biology. Since then, research into the cellular basis of reproduction has shown that sexual reproduction is the norm for the majority of eukaryotes, with huge consequences for their biology. The evolution of sex and some of its consequences are the subject of the series of reviews, and a Primer, in this special issue of Current Biology.

  17. Ethical considerations in sex selection.

    PubMed

    Eftekhaari, Tasnim Eghbal; Nejatizadeh, Abdol Azim; Rajaei, Minoo; Soleimanian, Saeede; Fallahi, Soghra; Ghaffarzadegan, Rahman; Mahmoudi, Forough

    2015-01-01

    Advances in modern medicine are resulted from unrestricted and unlimited research disregarding many essentials of a research including ethical issues. Following ethical issues, many of unwanted pregnancies and abortions can be avoided. Several factors such as medical issues including X linked disease, has encouraged couples to select traditional or modern techniques in selecting the gender of their children. Some of these methods are corrected Swim-up method or washing of spermatozoa, Percoll gradient sperm separation method, grass wool column filter method method, albumin separation method, microsort method using FISH (Fluorescence in situ hybridization), free electrophoresis method, Ph adjustment method, pre implantation genetic diagnosis (PGD)/fluorescence in situ hybridization. This technology is confronted with many ethical issues. Ethical considerations PGD in the SEX SELECTION differ in different religions and their perspectives on this issue. In this this review, electronic databases, books and Internet sites were completely searched and full articles including required keywords and techniques were obtained and reviewed. The rites and religions, were different and had legal perspectives and opinions about PGD. In some non-Islamic countries there are strict rules to control the use of technology. Some of these methods are costly and even risky. They also involve ethical issues such as legitimacy of the conceived fetus; recommending final touches in sex selection is still considered a taboo and a big issue in some cultures or mono-sexual families. Islamic views and beliefs are more flexible and the use of these technologies are allowed to preserve the health and lives permit. Islam strongly favors humanity and supports different issues if they are not in conflict with the primary concept of legitimate reproduction and are beneficial to human beings. PMID:26097846

  18. Studies of gonadal sex differentiation

    PubMed Central

    Makiyan, Zograb

    2016-01-01

    ABSTRACT Gonadal differentiation has a determinative influence on sex development in human embryos. Disorders of sexual development (DSD) have been associated with persistent embryonal differentiation stages. Between 1998 and 2015, 139 female patients with various (DSD) underwent operations at the Scientific Center of Obstetrics, Gynaecology and Perynatology in Moscow, Russia. Clinical investigations included karyotyping, ultrasound imaging, hormonal measurement and investigations of gonadal morphology. The male characteristics in the embryo are imposed by testicular hormones. When these are absent or inactive, the fetus may be arrested at between developmental stages, or stay on indifferent stage and become phenotypically female. A systematic analysis of gonadal morphology in DSD patients and a literature review revealed some controversies and led us to formulate a new hypothesis about sex differentiation. Proliferation of the mesonephric system (tubules and corpuscles) in the gonads stimulates the masculinization of gonads to testis. Sustentacular Sertoli cells of the testes are derived from mesonephric excretory tubules, while interstitial Leydig cells are derived from the original mesenchyme of the mesonephros. According of the new hypothesis, the original mesonephric cells (tubules and corpuscles) potentially persist in the ovarian parenchyma. In female gonads, some mesonephric excretory tubules regress and lose the tubular structure, but form ovarian theca interna and externa, becoming analogous to the sustentacular Sertoli cells in the testis. The ovarian interstitial Leydig cells are derived from intertubal mesenchyme of the mesonephros, similar to what occurs in male gonads (testis). Surprisingly, the leading determinative factor in sexual differentiation of the gonads is the mesonephros, represented by the embryonic urinary system. PMID:26950283

  19. Ethical considerations in sex selection

    PubMed Central

    Eftekhaari, Tasnim Eghbal; Nejatizadeh, Abdol Azim; Rajaei, Minoo; Soleimanian, Saeede; Fallahi, Soghra; Ghaffarzadegan, Rahman; Mahmoudi, Forough

    2015-01-01

    Advances in modern medicine are resulted from unrestricted and unlimited research disregarding many essentials of a research including ethical issues. Following ethical issues, many of unwanted pregnancies and abortions can be avoided. Several factors such as medical issues including X linked disease, has encouraged couples to select traditional or modern techniques in selecting the gender of their children. Some of these methods are corrected Swim-up method or washing of spermatozoa, Percoll gradient sperm separation method, grass wool column filter method method, albumin separation method, microsort method using FISH (Fluorescence in situ hybridization), free electrophoresis method, Ph adjustment method, pre implantation genetic diagnosis (PGD)/fluorescence in situ hybridization. This technology is confronted with many ethical issues. Ethical considerations PGD in the SEX SELECTION differ in different religions and their perspectives on this issue. In this this review, electronic databases, books and Internet sites were completely searched and full articles including required keywords and techniques were obtained and reviewed. The rites and religions, were different and had legal perspectives and opinions about PGD. In some non-Islamic countries there are strict rules to control the use of technology. Some of these methods are costly and even risky. They also involve ethical issues such as legitimacy of the conceived fetus; recommending final touches in sex selection is still considered a taboo and a big issue in some cultures or mono-sexual families. Islamic views and beliefs are more flexible and the use of these technologies are allowed to preserve the health and lives permit. Islam strongly favors humanity and supports different issues if they are not in conflict with the primary concept of legitimate reproduction and are beneficial to human beings. PMID:26097846

  20. The characteristics of online sex offenders: a meta-analysis.

    PubMed

    Babchishin, Kelly M; Hanson, R Karl; Hermann, Chantal A

    2011-03-01

    There is much debate as to whether online offenders are a distinct group of sex offenders or if they are simply typical sex offenders using a new technology. A meta-analysis was conducted to examine the extent to which online and offline offenders differ on demographic and psychological variables. Online offenders were more likely to be Caucasian and were slightly younger than offline offenders. In terms of psychological variables, online offenders had greater victim empathy, greater sexual deviancy, and lower impression management than offline offenders. Both online and offline offenders reported greater rates of childhood physical and sexual abuse than the general population. Additionally, online offenders were more likely to be Caucasian, younger, single, and unemployed compared with the general population. Many of the observed differences can be explained by assuming that online offenders, compared with offline offenders, have greater self-control and more psychological barriers to acting on their deviant interests.