The complex interplay between macronutrient intake, cuticular hydrocarbon expression and mating success in male decorated crickets.

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Rapkin, J; Jensen, K; House, C M; Sakaluk, S K; Sakaluk, J K; Hunt, J

2017-04-01

The condition dependence of male sexual traits plays a central role in sexual selection theory. Relatively little, however, is known about the condition dependence of chemical signals used in mate choice and their subsequent effects on male mating success. Furthermore, few studies have isolated the specific nutrients responsible for condition-dependent variation in male sexual traits. Here, we used nutritional geometry to determine the effect of protein (P) and carbohydrate (C) intake on male cuticular hydrocarbon (CHC) expression and mating success in male decorated crickets (Gryllodes sigillatus). We show that both traits are maximized at a moderate-to-high intake of nutrients in a P:C ratio of 1 : 1.5. We also show that female precopulatory mate choice exerts a complex pattern of linear and quadratic sexual selection on this condition-dependent variation in male CHC expression. Structural equation modelling revealed that although the effect of nutrient intake on mating success is mediated through condition-dependent CHC expression, it is not exclusively so, suggesting that other traits must also play an important role. Collectively, our results suggest that the complex interplay between nutrient intake, CHC expression and mating success plays an important role in the operation of sexual selection in G. sigillatus. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

Associations between body morphology, mating success and mate preferences among Slovak males and females.

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Prokop, Pavol; Fedor, Peter

2013-01-01

Human body morphology is thought to be correlated with sexual behaviour and sociosexuality (defined as an increased willingness to engage in sex without commitment) influences the perception of certain cues of physical attractiveness. Based on a sample of Slovak university students, we investigated relationships between 1) male and female mating success and reported body morphology (body mass index, BMI and waist-to-hip ratio, WHR) and 2) mate preference characteristics and mating success. Both males and females reported a similar number of long-term sexual partners and frequency of engaging in extra-pair copulation (EPC). The mating success of both sexes was positively mediated by self-perceived attractiveness. However, female BMI was inversely associated with mating success whereas increasing BMI was positively associated with male mating success (the total number of lifetime sexual partners) as well as with the likelihood of engaging in EPC. Unrestricted sociosexuality positively correlated with direct and indirect benefits from mating and negatively with the religious/political background of a potential mate and with the desire for a home/ children. These results confirm the hypothesis that human body morphology is associated with sexual behaviour and that cues of direct/indirect benefits in a potential mate positively correlate with sociosexuality.

The Relationship between Childhood Sexual Abuse and Adult Male Sexual Dysfunction.

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Sarwer, David B.; And Others

1997-01-01

A study of 359 men who sought sexual dysfunction treatment found that childhood sexual abuse did not predict sexual dysfunction in the men. Unemployment was the only significant predictor of male sexual dysfunction. Differences between the sexual abuse experiences of the male victims compared to female victims (n=73) are discussed. (Author/CR)

[Male sexual and reproductive rights].

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Diaz, A M

1998-06-01

In late 1997, PROFAMILIA began a study of the role of male sexual and reproductive rights as part of the construction of new masculine identities. The work was approached from the disciplines of law and sociology. Patriarchy, as a system of domination, permeated most cultures, giving men a position of power in relation to women and leading to a series of violent and self-destructive male behaviors. The patriarchal system imposed aggressive, promiscuous, risky, and irresponsible behaviors on men, which created a climate for sexual abuse, unwanted pregnancy, propagation of sexually transmitted diseases, and violence against women. Changes in female roles have created the need for changes in male roles. The most visible sexual and reproductive needs of men were studied through literature reviews and semistructured questionnaires with PROFAMILIA clients. Among the needs identified were a new type of male participation in family and domestic life, a new content for male sexual freedom, greater participation of men in reproductive decisions and in raising their children, and new ways of relating to others and sharing feelings and emotions. The need to avoid behaviors that put health at risk was also identified. A review of the evolution of existing sexual and reproductive rights and of the documents that constitute their ethical and juridical framework led to the conclusion that the construction of new rights specifically for men is not necessary, or juridically possible, in the current historical context.

Amyloid beta precursor protein regulates male sexual behavior.

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

2010-07-28

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

Sport and male sexuality.

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Sgrò, P; Di Luigi, L

2017-09-01

The relationships between sport and sexuality in males are of great social and clinical interest, because of sports and motor activities that highly promote social and sexual relationships. Even if few literature exist, two main questions should be taken into account: whether and how physical exercise and sport positively or negatively influence sexual health and behavior and/or whether and how sexual behavior may affect a sub-sequent sport performance. Physical exercise and sport per se can influence, positively or negatively, the hypothalamic-pituitary-testicular axis function and, consequently, the individual's reproductive and/or sexual health. This depends on individual factors such as genetic and epigenetic ones and on different variables involved in the practice of sport activities (type of sport, intensity and duration of training, doping and drug use and abuse, nutrition, supplements, psychological stress, allostatic load, etc.). If well conducted, motor and sport activities could have beneficial effects on sexual health in males. Among different lifestyle changes, influencing sexual health, regular physical activity is fundamental to antagonize the onset of erectile dysfunction (ED). However, competitive sport can lead both reproductive and/or sexual tract damages and dysfunctions, transient (genital pain, hypoesthesia of the genitalia, hypogonadism, DE, altered sexual drive, etc.) or permanent (hypogonadism, DE, etc.), by acting directly (traumas of the external genitalia, saddle-related disorders in cyclists, etc.) or indirectly (exercise-related hypogonadism, drug abuse, doping, stress, etc.). Sexual activities shortly performed before a sport competition could differently influence sport performance. Due to the few existing data, it is advisable to avoid an absolute pre-competition sexual abstinence.

Male Sexual Behavior and Pheromone Emission Is Enhanced by Exposure to Guava Fruit Volatiles in Anastrepha fraterculus.

Directory of Open Access Journals (Sweden)

Guillermo E Bachmann

Full Text Available Plant chemicals can affect reproductive strategies of tephritid fruit flies by influencing sex pheromone communication and increasing male mating competitiveness.We explored whether exposure of Anastrepha fraterculus males to guava fruit volatiles and to a synthetic blend of volatile compounds released by this fruit affects the sexual performance of wild and laboratory flies. By means of bioassays and pheromone collection we investigated the mechanism underlying this phenomenon.Guava volatile exposure enhanced male mating success and positively affected male calling behavior and pheromone release in laboratory and wild males. Changes in male behavior appear to be particularly important during the initial phase of the sexual activity period, when most of the mating pairs are formed. Exposure of laboratory males to a subset of guava fruit volatiles enhanced mating success, showing that the response to the fruit might be mimicked artificially.Volatiles of guava seem to influence male mating success through an enhancement of chemical and physical signals related to the communication between sexes. This finding has important implications for the management of this pest species through the Sterile Insect Technique. We discuss the possibility of using artificial blends to improve the sexual competitiveness of sterile males.

Review: neuroestrogen regulation of socio-sexual behavior of males.

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Ubuka, Takayoshi; Tsutsui, Kazuyoshi

2014-01-01

It is thought that estrogen (neuroestrogen) synthesized by the action of aromatase in the brain from testosterone activates male socio-sexual behaviors, such as aggression and sexual behavior in birds. We recently found that gonadotropin-inhibitory hormone (GnIH), a hypothalamic neuropeptide, inhibits socio-sexual behaviors of male quail by directly activating aromatase and increasing neuroestrogen synthesis in the preoptic area (POA). The POA is thought to be the most critical site of aromatization and neuroestrogen action for the regulation of socio-sexual behavior of male birds. We concluded that GnIH inhibits socio-sexual behaviors of male quail by increasing neuroestrogen concentration beyond its optimal concentration in the brain for expression of socio-sexual behavior. On the other hand, it has been reported that dopamine and glutamate, which stimulate male socio-sexual behavior in birds and mammals, inhibit the activity of aromatase in the POA. Multiple studies also report that the activity of aromatase or neuroestrogen is negatively correlated with changes in male socio-sexual behavior in fish, birds, and mammals including humans. Here, we review previous studies that investigated the role of neuroestrogen in the regulation of male socio-sexual behavior and reconsider the hypothesis that neuroestrogen activates male socio-sexual behavior in vertebrates. It is considered that basal concentration of neuroestrogen is required for the maintenance of male socio-sexual behavior but higher concentration of neuroestrogen may inhibit male socio-sexual behavior.

Males that drop a sexually selected weapon grow larger testes.

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Joseph, Paul N; Emberts, Zachary; Sasson, Daniel A; Miller, Christine W

2018-01-01

Costly sexually selected weapons are predicted to trade off with postcopulatory traits, such as testes. Although weapons can be important for achieving access to females, individuals of some species can permanently drop (i.e. autotomize) their weapons, without regeneration, to escape danger. We capitalized on this natural behavior to experimentally address whether the loss of a sexually selected weapon leads to increased testes investment in the leaf-footed cactus bug, Narnia femorata Stål (Hemiptera: Coreidae). In a second experiment, we measured offspring production for males that lost a weapon during development. As predicted, males that dropped a hind limb during development grew significantly larger testes than the control treatments. Hind-limb autotomy did not result in the enlargement of other nearby traits. Our results are the first to experimentally demonstrate that males compensate for natural weapon loss by investing more in testes. In a second experiment we found that females paired with males that lost a hind limb had 40% lower egg hatching success than females paired with intact males, perhaps because of lower mating receptivity to males with a lost limb. Importantly, in those cases where viable offspring were produced, males missing a hind limb produced 42% more offspring than males with intact limbs. These results suggest that the loss of a hind-limb weapon can, in some cases, lead to greater fertilization success. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

Sexual Success after Stress? Imidacloprid-Induced Hormesis in Males of the Neotropical Stink Bug Euschistus heros

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Haddi, Khalid; Mendes, Marcos V.; Lino-Neto, José; Freitas, Hemerson L.; Guedes, Raul Narciso C.; Oliveira, Eugênio E.

2016-01-01

Environmental stress in newly-emerged adult insects can have dramatic consequences on their life traits (e.g., dispersion, survival and reproduction) as adults. For instance, insects sublethally exposed to environmental stressors (e.g., insecticides) can gain fitness benefits as a result of hormesis (i.e., benefits of low doses of compounds that would be toxic at higher doses). Here, we experimentally tested whether sublethal exposure to the insecticide imidacloprid would hormetically affect the sexual fitness of newly-emerged adults of the Neotropical brown stink bug Euschistus heros (Hemiptera: Heteroptera: Pentatomidae), which is the most abundant and prevalent insect pest in Neotropical soybean fields. We evaluated the sexual fitness of four couple combinations: unexposed couples, exposed females, exposed males, and exposed couples. Sublethal exposure to dry residues (i.e., contact) of imidacloprid (at 1% of recommended field rate) did not affect insect survival, but led to higher mating frequencies when at least one member of the couple was exposed. However, the average mating duration was shortened when only females were exposed to imidacloprid. Moreover, exposed males showed higher locomotory (walking) activity, lower respiration rates and induced higher fecundity rates when mated to unexposed females. Although the reproductive tracts of exposed males did not differ morphometrically from unexposed males, their accessory glands exhibited positive reactions for acidic and basic contents. Our findings suggest that males of the Neotropical brown stink bug hormetically increase their sexual fitness when cued by impending insecticidal stress in early adulthood. PMID:27284906

Sexual Success after Stress? Imidacloprid-Induced Hormesis in Males of the Neotropical Stink Bug Euschistus heros.

Directory of Open Access Journals (Sweden)

Khalid Haddi

Full Text Available Environmental stress in newly-emerged adult insects can have dramatic consequences on their life traits (e.g., dispersion, survival and reproduction as adults. For instance, insects sublethally exposed to environmental stressors (e.g., insecticides can gain fitness benefits as a result of hormesis (i.e., benefits of low doses of compounds that would be toxic at higher doses. Here, we experimentally tested whether sublethal exposure to the insecticide imidacloprid would hormetically affect the sexual fitness of newly-emerged adults of the Neotropical brown stink bug Euschistus heros (Hemiptera: Heteroptera: Pentatomidae, which is the most abundant and prevalent insect pest in Neotropical soybean fields. We evaluated the sexual fitness of four couple combinations: unexposed couples, exposed females, exposed males, and exposed couples. Sublethal exposure to dry residues (i.e., contact of imidacloprid (at 1% of recommended field rate did not affect insect survival, but led to higher mating frequencies when at least one member of the couple was exposed. However, the average mating duration was shortened when only females were exposed to imidacloprid. Moreover, exposed males showed higher locomotory (walking activity, lower respiration rates and induced higher fecundity rates when mated to unexposed females. Although the reproductive tracts of exposed males did not differ morphometrically from unexposed males, their accessory glands exhibited positive reactions for acidic and basic contents. Our findings suggest that males of the Neotropical brown stink bug hormetically increase their sexual fitness when cued by impending insecticidal stress in early adulthood.

Sexual Harassment by Males Reduces Female Fecundity in the Alfalfa Leafcutting Bee (Megachile rotundata)

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Under sexual conflict, males evolve traits to increase their mating and reproductive success that impose costs on females. Females evolve counter-adaptations to resist males and reduce those costs. Female resistance may instead serve as a mechanism for mate choice if the male-imposed costs are outwe...

Male Sexual Behavior and Pheromone Emission Is Enhanced by Exposure to Guava Fruit Volatiles in Anastrepha fraterculus

Science.gov (United States)

Bachmann, Guillermo E.; Segura, Diego F.; Devescovi, Francisco; Juárez, M. Laura; Ruiz, M. Josefina; Vera, M. Teresa; Cladera, Jorge L.; Fernández, Patricia C.

2015-01-01

Background Plant chemicals can affect reproductive strategies of tephritid fruit flies by influencing sex pheromone communication and increasing male mating competitiveness. Objective and Methodology We explored whether exposure of Anastrepha fraterculus males to guava fruit volatiles and to a synthetic blend of volatile compounds released by this fruit affects the sexual performance of wild and laboratory flies. By means of bioassays and pheromone collection we investigated the mechanism underlying this phenomenon. Results Guava volatile exposure enhanced male mating success and positively affected male calling behavior and pheromone release in laboratory and wild males. Changes in male behavior appear to be particularly important during the initial phase of the sexual activity period, when most of the mating pairs are formed. Exposure of laboratory males to a subset of guava fruit volatiles enhanced mating success, showing that the response to the fruit might be mimicked artificially. Conclusions Volatiles of guava seem to influence male mating success through an enhancement of chemical and physical signals related to the communication between sexes. This finding has important implications for the management of this pest species through the Sterile Insect Technique. We discuss the possibility of using artificial blends to improve the sexual competitiveness of sterile males. PMID:25923584

The Sexual Stereotype of the Black Male.

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Davis, Gary L.; Cross, Herbert J.

This paper presents the results of a study to examine the existence of sexual stereotyping of black males by white college students. Subjects were 180 male and 180 female white undergraduates; they were tested in sexually segregated groups. Each read one of three types of pornographic stories (hard-core, erotic realism, or sexual fantasy). The…

The form of sexual selection arising from male-male competition depends on the presence of females in the social environment.

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Procter, D S; Moore, A J; Miller, C W

2012-05-01

Sexual selection arises from social interactions, and if social environments vary so too should sexual selection. For example, male-male competition often occurs either in the presence or in the absence of females, and such changes in the social environment could affect the form and strength of sexual selection. Here we examine how the presence of a female influences selection arising from male-male competition in a leaf-footed cactus bug, Narnia femorata, which has a resource defence mating system. Males compete for territories on cacti because females lay eggs on the cactus plants. Females are not always present when this competition first occurs; however, the presence or absence of the female matters. We found that both the form and strength of selection on male traits, those traits that influenced success in intrasexual competition, depended on the social context. When a female was not present, male size and the area of the sexually dimorphic hind legs was only marginally important to winning a contest. However, males with larger overall size and leg area were more likely to win in the presence of a female. There was also positive quadratic selection on these traits when a female was present with both the largest and the smallest males winning. The implication is unexpected alternative strategies when females are present. Our results support the notion that sexual selection should be studied under all relevant social contexts. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

Sexual Arousal Patterns of Autogynephilic Male Cross-Dressers.

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Hsu, Kevin J; Rosenthal, A M; Miller, David I; Bailey, J Michael

2017-01-01

Men's sexual arousal patterns have been an important window into the nature of their erotic interests. Autogynephilia is a natal male's paraphilic tendency to be sexually aroused by the thought or image of being a woman. Autogynephilic arousal per se is difficult to assess objectively, because it is inwardly focused. However, assessing sexual arousal patterns of autogynephilic males in response to external stimuli is also potentially useful. For example, there is substantial association between autogynephilia and gynandromorphophilia (GAMP), or sexual attraction to gynandromorphs (GAMs), colloquially "she-males." GAMP men's sexual arousal patterns in response to GAM, female, and male stimuli have recently been characterized. In the present study, we extended this understanding by comparing the sexual arousal patterns of autogynephilic male cross-dressers, GAMP men, heterosexual men, and homosexual men. Erotic stimuli included sexually explicit videos of men, women, and GAMs. Autogynephilic men were much more similar in their arousal patterns to heterosexual and GAMP men than to homosexual men. However, similar to GAMP men, autogynephilic men showed increased arousal by GAM stimuli relative to female stimuli compared with heterosexual men.

Sexual Homicide by Older Male Offenders.

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Myers, Wade C; Chan, Heng Choon Oliver; Mariano, Timothy Y; Safarik, Mark E; Geberth, Vernon J

2017-07-01

Recent research has expanded our understanding of sexual homicide offenders (SHOs). However, little exists beyond case reports for older SHOs. We characterized male SHOs ≥ 55 years, comparing them to typical adult male SHOs who are in their 20s. Analysis of 37 years (1976-2012) of US Supplementary Homicide Reports data provided a large SHO sample (N = 3453). Three case reports provide clinical context for the diverse nature and patterns of older SHOs. Only 32 older male SHOs and no older female SHOs were identified. Murders by older SHOs accounted for only 0.5% of US sexual homicides. Unlike typical SHOs that generally target young adult females, over two-thirds of older SHO victims were ≥40 years, and one-third were ≥55 years. Sexual homicides by older SHOs, like sexual homicide in general, decreased over the study period. These crimes, while exceedingly rare, do occur, warranting special consideration. © 2017 American Academy of Forensic Sciences.

Do extra-group fertilizations increase the potential for sexual selection in male mammals?

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Isvaran, Kavita; Sankaran, Sumithra

2017-10-01

Fertilizations by males outside the social breeding group (extra-group paternity, EGP) are widespread in birds and mammals. EGP is generally proposed to increase male reproductive skew and thereby increase the potential for sexual selection, but the generality of this relationship is unclear. We extracted data from 27 mammals in seven orders and used phylogenetic comparative methods to investigate the influence of EGP and social mating system on measures of inequality in male fertilization success, which are indices of the potential for sexual selection. We find that EGP and social mating system can predict the potential for sexual selection in mammalian populations, but only when considered jointly and not individually. EGP appears to increase the potential for sexual selection but only when the degree of social polygyny is relatively low. When social polygyny is high, EGP appears to result in a more uniform distribution of reproduction and a decrease in the potential for sexual selection. A possible explanation to be investigated is that the phenotype of extra-group fathers differs systematically across social mating systems. Our findings have implications for the use of EGP and social mating system as indices of sexual selection in comparative analyses of trait evolution under sexual selection. © 2017 The Author(s).

Sexual selection on male size drives the evolution of male-biased sexual size dimorphism via the prolongation of male development.

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Rohner, Patrick T; Blanckenhorn, Wolf U; Puniamoorthy, Nalini

2016-06-01

Sexual size dimorphism (SSD) arises when the net effects of natural and sexual selection on body size differ between the sexes. Quantitative SSD variation between taxa is common, but directional intraspecific SSD reversals are rare. We combined micro- and macroevolutionary approaches to study geographic SSD variation in closely related black scavenger flies. Common garden experiments revealed stark intra- and interspecific variation: Sepsis biflexuosa is monomorphic across the Holarctic, while S. cynipsea (only in Europe) consistently exhibits female-biased SSD. Interestingly, S. neocynipsea displays contrasting SSD in Europe (females larger) and North America (males larger), a pattern opposite to the geographic reversal in SSD of S. punctum documented in a previous study. In accordance with the differential equilibrium model for the evolution of SSD, the intensity of sexual selection on male size varied between continents (weaker in Europe), whereas fecundity selection on female body size did not. Subsequent comparative analyses of 49 taxa documented at least six independent origins of male-biased SSD in Sepsidae, which is likely caused by sexual selection on male size and mediated by bimaturism. Therefore, reversals in SSD and the associated changes in larval development might be much more common and rapid and less constrained than currently assumed. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

Male Escorts' and Male Clients' Sexual Behavior During Their Last Commercial Sexual Encounter: Comparing and Contrasting Findings from Two Online Studies.

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Grov, Christian; Rodríguez-Díaz, Carlos E; Jovet-Toledo, Gerardo G

2016-05-01

Much of what is known about commercial sexual encounters between men is based on data gathered from escorts. With few exceptions, studies have not compared male clients' reports of behavior during commercial sexual encounters with male escorts'. The present study draws from two datasets, a 2012 survey of clients (n = 495) and a 2013 survey of escorts (n = 387)--both used virtually identical measures of sexual behavior during the most recent commercial sexual encounter. For clients and escorts, the majority eschewed having sex without a condom, and kissing and oral sex were among the most common behaviors reported. Using logistic regression, both samples were compared across 15 sexual behaviors, finding significant differences in six--the escort sample had greater odds of reporting their last commercial sexual encounter involved watching the client masturbate, viewing porn, role play (dad/son, dominant/submissive), and having prior sexual experience with their commercial partner. The escort sample had lower odds of reporting that the client watched the escort masturbate, and being told partner's HIV status. In multivariable modeling, both samples did not significantly differ in reports of condomless anal sex. Male-male commercial sexual encounters appear to be involved in a wide range of sexual behaviors, many of which convey low-to-no risk of HIV transmission.

Conceptual model of male military sexual trauma.

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Elder, William B; Domino, Jessica L; Rentz, Timothy O; Mata-Galán, Emma L

2017-08-01

Male sexual trauma is understudied, leaving much to be known about the unique mental health needs of male survivors. This study examined veteran men's perceptions of the effects of military sexual trauma. Military sexual trauma was defined as physically forced, verbally coerced, or substance-incapacitated acts experienced during military service. Interviews were conducted with 21 male veterans who reported experiencing military sexual trauma. Data were drawn together using a grounded theory methodology. Three categories emerged from data analysis, including (a) types of military sexual trauma (being touched in a sexual way against their will [N = 18]; sexual remarks directed at them [N = 15]; being physically forced to have sex [N = 13]); (b) negative life effects (difficulty trusting others [N = 18]; fear of abandonment [N = 17]; substance use [N = 13]; fear of interpersonal violence [N = 12]; conduct and vocational problems [N = 11]; irritability/aggression [N = 8]; insecurity about sexual performance [N = 8]; difficulty managing anger [N = 8]); and (c) posttraumatic growth (N = 15). Results from this study suggest sexual trauma in the military context may affect systems of self-organization, specifically problems in affective, self-concept, and relational domains, similar to symptoms of those who have experienced prolonged traumatic stressors. This model can be used by clinicians to select treatments that specifically target these symptoms and promote posttraumatic growth. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Male rank affects reproductive success and offspring performance in bank voles.

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Kruczek, Małgorzata; Zatorska, Magdalena

2008-07-05

Laboratory studies reveal that in several rodent species the females prefer dominant males as mating partners. Here we investigate the correlation between males' social rank and their reproductive success. Similar numbers of females mating with relatively more dominant or relatively more subordinate males produced a litter, and parturition took place 19-21 days after mating. Relatively more dominant males tended to sire more pups than did relatively more subordinates, but the mean number of offspring per litter did not differ significantly between the two groups. Significantly more pups fathered by relatively more dominant males survived to weaning than those sired by relatively more subordinate fathers. Dominance had a long-term effect on the reproductive activity of the offspring: their rate of sexual maturation was increased. In pups sired by a relatively more dominant father, the uteruses of females, and the testes and accessory sex glands of males, were significantly heavier than those of offspring born to relatively more subordinate males. Our results suggest that social rank is an important determinant of the reproductive success of bank vole males.

Sneaker Males Affect Fighter Male Body Size and Sexual Size Dimorphism in Salmon.

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Weir, Laura K; Kindsvater, Holly K; Young, Kyle A; Reynolds, John D

2016-08-01

Large male body size is typically favored by directional sexual selection through competition for mates. However, alternative male life-history phenotypes, such as "sneakers," should decrease the strength of sexual selection acting on body size of large "fighter" males. We tested this prediction with salmon species; in southern populations, where sneakers are common, fighter males should be smaller than in northern populations, where sneakers are rare, leading to geographical clines in sexual size dimorphism (SSD). Consistent with our prediction, fighter male body size and SSD (fighter male∶female size) increase with latitude in species with sneaker males (Atlantic salmon Salmo salar and masu salmon Oncorhynchus masou) but not in species without sneakers (chum salmon Oncorhynchus keta and pink salmon Oncorhynchus gorbuscha). This is the first evidence that sneaker males affect SSD across populations and species, and it suggests that alternative male mating strategies may shape the evolution of body size.

Do male secondary sexual characters signal ejaculate quality? A meta-analysis.

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Mautz, Brian S; Møller, Anders P; Jennions, Michael D

2013-08-01

There are two reasons why researchers are interested in the phenotypic relationship between the expression of male secondary sexual characters (SSCs) and 'ejaculate quality' (defined as sperm/ejaculate traits that are widely assumed to increase female fertility and/or sperm competitiveness). First, if the relationship is positive then females could gain a direct benefit by choosing more attractive males for fertility assurance reasons ('the phenotype-linked fertility' hypothesis). Second, there is much interest in the direction of the correlation between traits favoured by pre-copulatory sexual selection (i.e. affecting mating success) and those favoured by post-copulatory sexual selection (i.e. increasing sperm competitiveness). If the relationship is negative this could lead to the two forms of selection counteracting each other. Theory predicts that the direction of the relationship could be either positive or negative depending on the underlying genetic variance and covariance in each trait, the extent of variation among males in condition (resources available to allocate to reproductive traits), and variation among males in the cost or rate of mating. We conducted a meta-analysis to determine the average relationship between the expression of behavioural and morphological male secondary sexual characters and four assays of ejaculate quality (sperm number, viability, swimming speed and size). Regardless of how the data were partitioned the mean relationship was consistently positive, but always statistically non-significant. The only exception was that secondary sexual character expression was weakly but significantly positively correlated with sperm viability (r = 0.07, P < 0.05). There was no significant difference in the strength or direction of the relationship between behavioural and morphological SSCs, nor among relationships using the four ejaculate quality assays. The implications of our findings are discussed. © 2013 The Authors. Biological Reviews �

The mesolimbic system participates in the naltrexone-induced reversal of sexual exhaustion: opposite effects of intra-VTA naltrexone administration on copulation of sexually experienced and sexually exhausted male rats.

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Garduño-Gutiérrez, René; León-Olea, Martha; Rodríguez-Manzo, Gabriela

2013-11-01

Male rats allowed to copulate until reaching sexual exhaustion exhibit a long-lasting sexual behavior inhibition (around 72 h) that can be reversed by systemic opioid receptor antagonist administration. Copulation activates the mesolimbic dopaminergic system (MLS) and promotes endogenous opioid release. In addition, endogenous opioids, acting at the ventral tegmental area (VTA), modulate the activity of the MLS. We hypothesized that endogenous opioids participate in the sexual exhaustion phenomenon by interacting with VTA opioid receptors and consequently, its reversal by opioid antagonists could be exerted at those receptors. In this study we determined the effects of intra-VTA infusion of different doses of the non-specific opioid receptor antagonist naltrexone (0.1-1.0 μg/rat) on the already established sexual behavior inhibition of sexually exhausted male rats. To elucidate the possible involvement of VTA δ-opioid receptors in the naltrexone-mediated reversal of sexual exhaustion, the effects of different doses of the selective δ-opioid receptor antagonist, naltrindole (0.03-1.0 μg/rat) were also tested. Results showed that intra-VTA injection of 0.3 μg naltrexone reversed the sexual inhibition of sexually exhausted rats, evidenced by an increased percentage of animals capable of showing two successive ejaculations. Intra-VTA infused naltrindole did not reverse sexual exhaustion at any dose. It is concluded that the MLS is involved in the reversal of sexual exhaustion induced by systemic naltrexone, and that μ-, but not δ-opioid receptors participate in this effect. Intra-VTA naltrexone infusion to sexually experienced male rats had an inhibitory effect on sexual activity. The opposite effects of intra-VTA naltrexone on male rat sexual behavior expression of sexually experienced and sexually exhausted rats is discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

Sexual Dysfunction in Males: Significance of Adverse Childhood Experiences.

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Kinzl, Johann F.; And Others

1996-01-01

A survey of 301 male college students found that occasional sexual dysfunction was frequent in young male adults, and long-lasting adverse familial relationships to attachment figures were more influential in later sexual dysfunction than were childhood sexual abuse experiences. (Author/DB)

Syndemics and gender affirmation: HIV sexual risk in female-to-male trans masculine adults reporting sexual contact with cisgender males.

Science.gov (United States)

Reisner, Sari L; White Hughto, Jaclyn M; Pardee, Dana; Sevelius, Jae

2016-10-01

Female-to-male trans masculine adults who have sex with cisgender (non-transgender) males (TMSM) represent an understudied population in relation to HIV/sexually transmitted infection (STI) risk. This study examined the role of syndemic conditions and social gender affirmation processes (living full-time in one's identified gender) in potentiating sexual risk among TMSM adults in Massachusetts, US. Cross-sectional data were restricted to TMSM who reported lifetime sexual behaviour with a cisgender male (n = 173; mean age = 29.4, SD = 9.6; 18.5% people of colour; 93.1% non-heterosexual identity; 56.1% hormones/surgery). Sexual risk outcomes were: lifetime STI diagnoses, three or more sexual partners in the previous six months, and condomless anal/vaginal sex at last encounter with a cisgender male. Age- and survey mode-adjusted logistic regression models regressed sexual risk outcomes on the main effect of syndemics (six indicators summed: binge drinking, substance use, depression, anxiety, childhood abuse, intimate partner violence), followed by the interaction of syndemics and social gender affirmation. Syndemics were associated with increased odds of all sexual risk indicators (adjusted odds ratios [aORs] = 1.32-1.55; p < 0.0001). Social gender affirmation moderated the association between syndemics and condomless anal/vaginal sex at last encounter with a cisgender male (p < 0.0001). Syndemics were associated with sexual risk in TMSM who had socially affirmed their gender (aOR = 1.79; 95% CI = 1.42-2.25; p < 0.001), but not among those TMSM who had not (aOR = 0.86; 95% CI = 0.63-1.19; p = 0.37). Findings suggest that syndemic pathways to sexual risk are similar for TMSM who have socially gender affirmed as for cisgender MSM. Integration of syndemics and gender affirmation frameworks is recommended in interventions to address TMSM sexual risk. © The Author(s) 2016.

Dopamine, the medial preoptic area, and male sexual behavior.

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Dominguez, Juan M; Hull, Elaine M

2005-10-15

The medial preoptic area (MPOA), at the rostral end of the hypothalamus, is important for the regulation of male sexual behavior. Results showing that male sexual behavior is impaired following MPOA lesions and enhanced with MPOA stimulation support this conclusion. The neurotransmitter dopamine (DA) facilitates male sexual behavior in all studied species, including rodents and humans. Here, we review data indicating that the MPOA is one site where DA may act to regulate male sexual behavior. DA agonists microinjected into the MPOA facilitate sexual behavior, whereas DA antagonists impair copulation, genital reflexes, and sexual motivation. Moreover, microdialysis experiments showed increased release of DA in the MPOA as a result of precopulatory exposure to an estrous female and during copulation. DA may remove tonic inhibition in the MPOA, thereby enhancing sensorimotor integration, and also coordinate autonomic influences on genital reflexes. In addition to sensory stimulation, other factors influence the release of DA in the MPOA, including testosterone, nitric oxide, and glutamate. Here we summarize and interpret these data.

Generational differences in male sexuality that may affect ...

African Journals Online (AJOL)

Objective: To determine generational differences in male sexuality, which could predispose men's female sexual partners to STDs/HlV. Design: Cross-sectional study. Setting: Harare, Zimbabwe. Subjects: Three hundred and ninety seven male adults aged eighteen years and above. Main outcome measures: Number of ...

A discourse analysis of male sexuality in the magazine Intimacy.

Science.gov (United States)

du Plessis, Rory

2015-03-19

The World Health Organization's publication, Developing sexual health programmes, states that the media is an important source of information about sexuality. Although the media can promote awareness of sexual health issues, it also acts as a vehicle for defining and regulating sex norms. In other words, the standards of 'normal' sex are in part defined by the media. Accordingly, it has become imperative to analyse the media's construction of sexual norms in order to reveal how they are related to specific ideological views. For the purposes of this study, the focus will be limited to analysing the South African publication Intimacy. The study aims to reveal how the sex advice articles written in Intimacy for women in regard to their male partner's sexuality reflect patriarchal and phallocentric ideologies. A discourse analysis of the sex advice articles in the magazine Intimacy was conducted. It was informed by feminist theories of sexuality that seek to examine the ways in which texts are associated with male-centred versions of sexual pleasure. The discourse analysis identified a number of key themes regarding male sexuality. These include: (1) biological accounts of male sexuality; (2) phallocentric scripting of the sex act; and (3) the melodramatic penis. Constructions of male sexuality require the inclusion of alternative modes of male erotic pleasure. This requires texts that encourage men to explore and also to experiment with pleasurable feelings associated with non-genital erogenous zones of the body.

Sexual Dysfunction and Sexual Behaviors in a Sample of Brazilian Male Substance Misusers.

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Diehl, Alessandra; Pillon, Sandra Cristina; Dos Santos, Manoel Antônio; Rassool, G Hussein; Laranjeira, Ronaldo

2016-09-01

The aim of this study was to evaluate the potential relationship between self-reported sexual dysfunction, sexual behavior, and severity of addiction of drug users. A cross-sectional design study was conducted at an inpatient addiction treatment unit in Sao Paulo, Brazil, with a sample of 508 male drug users. Sociodemographic data, sexual behavior, and severity of dependence were evaluated.The prevalence of sexual dysfunction was 37.2% and premature ejaculation was 63.8%. Men with sexual dysfunction presented from moderate to severe level of alcohol, tobacco, and other drugs of dependence. The findings from this study are particularly relevant identifying those sociodemographic factors, severity of drug use, and sexual behavior are related to men who experience sexual dysfunction. Health promotion and motivational interventions on sexual health targeted to male drug users can contribute in reducing these at-risk behaviors. More interdisciplinary research is desirable in future in considering men's sexual health. © The Author(s) 2015.

Sexual orientation and sexual risk behaviors among male students of a university in southern Thailand.

Science.gov (United States)

Sureerut, Rongruang; Assanangkornchai, Sawitri; Chongsuvivatwong, Virasakdi; Duangmala, Padoongyot

2013-09-01

To determine the prevalence of sexual orientation, identify predictors of being homosexual or bisexual (HB), and assess the association of sexual orientation with sexual risk behaviors among university male students in southern Thailand. A cross-sectional study was conducted on third year male university students between June 2008 and February 2009 using anonymous self-administered questionnaires. Among 1,101 eligible students, 1,013 (92%) responded The prevalence of heterosexuality, homosexuality, and bisexuality among respondents were 90.2%, 6.7%, and 3.1%, respectively giving a prevalence of HB of 9.8%. Significant factors predicting HB included having separated parents. Overall lifetime prevalence of men having sex with men (MSM) was 6.3% (2% in heterosexual males and 46.5% among HB males). HB males were more likely to have multiple sex partners and engage in group sex, and less likely to use condoms than were heterosexual males. The prevalence of sexual risk behaviors among these male students, especially HB, was high.

Sexual Objectification of Pinoy Males in Billboard Advertisements

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Agon Pacoma Marc

2017-01-01

Full Text Available Male models in skimpy undergarments showing their Adonislike physique, presented in sexualized poses with disturbing bulges or crotches is one of the common landscapes in the Philippine advertising today. The author found the conflicting idea of a nation rich in morals, values and principles but endure high profanity or obscenity through sexualized male bodies as seen in billboards of fashion brands and gratification of visual desire among its spectators. Advertising promotes this phenomenon stimulating the idea that sex truly sells, male models are objectified as sexual objects capturing consumers’ attention resulting to persuasion and eventual consumption of the product. Ads showing Pinoy males’ chiselled bodies in silhouettes communicating sexual innuendos constitute a contemporary marketing technique; a ploy for companies to earn profit yet an avenue for public scrutiny and moral outcry.

Does Halitosis Effect Sexual Life in Males?

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Gul Soylu Ozler

2014-03-01

Full Text Available Aim: Halitosis is an unpleasant alteration of the halitus. The aim of the study is to assess the quality of sexual life of males with and without halitosis. Material and Method: Males between 20-50 years old; with a complaint of halitosis; married and able to complete the study were included in the study. The control group were healthy, adult, married males who have normal otorhinolaryngologic examination. The International Index of Erectile Function questionnaire(IIEF were used to assess the quality of sexual life  of males with halitosis and the results were compared with a similar group of healthy men. Results: A total of 80 adult subjects completed the study. When the groups were compared in terms of age, body mass index(BMI and duration of marriage, they were similar (p=0.65, p= 0.20, p= 0.08 respectively.The halitosis group had significantly lower scores for all function domains (p=0.0001.There was no correlation between degree of halitosis and the scores of IIEF (p< 0.05. Discussion: This is the first study investigating the sexual health of males with halitosis. Halitosis not only effects oral health status but also strongly declines quality of life. The otorhinolaryngologist must not only treat halitosis but also help the patient to stand up to social and sexual problems concomitting halitosis.

Copulation is reactivated by bromocriptine in male rats after reaching sexual satiety with a same sexual mate.

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Rojas-Hernández, Jorge; Juárez, Jorge

2015-11-01

Male sexual satiety has been associated with a decrease in dopamine levels. Spontaneous recovery of copulatory behavior begins at least 72 h after sexual satiety is reached or in the condition in which a sexually-satiated male is exposed to a new receptive female distinct from the one with which sexual satiety was reached. The aim of the present study was to explore whether dopaminergic activation by bromocriptine (BrCr) can reactivate copulatory behavior with the same sexual mate immediately after sexual satiety is reached. Male rats were divided into three groups exposed to one of the following three conditions: 1) administration of 2 mg/kgs.c. of BrCr and exposure to the same female with whom sexual satiety was previously reached; 2) administration of 0.3 mLs.c. of the vehicle solution with exposure to the same female with whom sexual satiety was reached; and, 3) exposure to a new receptive female after sexual satiety was reached. Results showed that BrCr significantly reactivated copulatory capability in sexually-satiated males with the same receptive female. In contrast, no males in the vehicle group ejaculated with the same female after reaching sexual exhaustion. Copulation was reactivated by BrCr in a way similar to that observed in untreated males exposed to a new receptive female (i.e., the Coolidge effect). The reversal of sexual satiety in the males treated with BrCr could be explained by its action on D2 family receptors, which promotes a reactivation of sexual motivation at a level sufficient to allow renewed copulation with the same female mate. Copyright © 2015 Elsevier Inc. All rights reserved.

A discourse analysis of male sexuality in the magazine Intimacy

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Rory du Plessis

2015-03-01

Full Text Available Background: The World Health Organization’s publication, Developing sexual health programmes, states that the media is an important source of information about sexuality. Although the media can promote awareness of sexual health issues, it also acts as a vehicle for defining and regulating sex norms. In other words, the standards of ‘normal’ sex are in part defined by the media. Accordingly, it has become imperative to analyse the media’s construction of sexual norms in order to reveal how they are related to specific ideological views. For the purposes of this study, the focus will be limited to analysing the South African publication Intimacy. Aim: The study aims to reveal how the sex advice articles written in Intimacyfor women in regard to their male partner’s sexuality reflect patriarchal and phallocentric ideologies. Method: A discourse analysis of the sex advice articles in the magazine Intimacy was conducted. It was informed by feminist theories of sexuality that seek to examine the ways in which texts are associated with male-centred versions of sexual pleasure. Results: The discourse analysis identified a number of key themes regarding male sexuality. These include: (1 biological accounts of male sexuality; (2 phallocentric scripting of the sex act; and (3 the melodramatic penis. Conclusion: Constructions of male sexuality require the inclusion of alternative modes of male erotic pleasure. This requires texts that encourage men to explore and also to experiment with pleasurable feelings associated with non-genital erogenous zones of the body.

A thermogenic secondary sexual character in male sea lamprey

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Chung-Davidson, Yu-Wen; Priess, M. Cody; Yeh, Chu-Yin; Brant, Cory O.; Johnson, Nicholas S.; Li, Ke; Nanlohy, Kaben G.; Bryan, Mara B.; Brown, C. Titus; Choi, Jongeun; Li, Weiming

2013-01-01

Secondary sexual characters in animals are exaggerated ornaments or weapons for intrasexual competition. Unexpectedly, we found that a male secondary sexual character in sea lamprey (Petromyzon marinus ) is a thermogenic adipose tissue that instantly increases its heat production during sexual encounters. This secondary sexual character, developed in front of the anterior dorsal fin of mature males, is a swollen dorsal ridge known as the ‘rope’ tissue. It contains nerve bundles, multivacuolar adipocytes and interstitial cells packed with small lipid droplets and mitochondria with dense and highly organized cristae. The fatty acid composition of the rope tissue is rich in unsaturated fatty acids. The cytochrome c oxidase activity is high but the ATP concentration is very low in the mitochondria of the rope tissue compared with those of the gill and muscle tissues. The rope tissue temperature immediately rose up to 0.3°C when the male encountered a conspecific. Mature males generated more heat in the rope and muscle tissues when presented with a mature female than when presented with a male (paired t-test, P-3 more heat than the muscle in 10 min. Transcriptome analyses revealed that genes involved in fat cell differentiation are upregulated whereas those involved in oxidative-phosphorylation-coupled ATP synthesis are downregulated in the rope tissue compared with the gill and muscle tissues. Sexually mature male sea lamprey possess the only known thermogenic secondary sexual character that shows differential heat generation toward individual conspecifics.

Sexual Excitability and Dysfunctional Coping Determine Cybersex Addiction in Homosexual Males.

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Laier, Christian; Pekal, Jaro; Brand, Matthias

2015-10-01

Cybersex addiction (CA) has been mostly investigated in heterosexual males. Recent findings have demonstrated an association between CA severity and indicators of sexual excitability, and that coping by sexual behaviors mediated the relationship between sexual excitability and CA symptoms. The aim of this study was to test this mediation in a sample of homosexual males. Seventy-one homosexual males were surveyed online. Questionnaires assessed symptoms of CA, sensitivity to sexual excitation, pornography use motivation, problematic sexual behavior, psychological symptoms, and sexual behaviors in real life and online. Moreover, participants viewed pornographic videos and indicated their sexual arousal before and after the video presentation. Results showed strong correlations between CA symptoms and indicators of sexual arousal and sexual excitability, coping by sexual behaviors, and psychological symptoms. CA was not associated with offline sexual behaviors and weekly cybersex use time. Coping by sexual behaviors partially mediated the relationship between sexual excitability and CA. The results are comparable with those reported for heterosexual males and females in previous studies and are discussed against the background of theoretical assumptions of CA, which highlight the role of positive and negative reinforcement due to cybersex use.

Are larger and/or more symmetrical Drosophila melanogaster (Diptera, Drosophilidae males more successful in matings in nature?

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Sofija Pavković-Lučić

Full Text Available Are larger and/or more symmetrical Drosophila melanogaster (Diptera, Drosophilidae males more successful in matings in nature? Sexual selection in Drosophila melanogaster, related to body size and fluctuating asymmetry in wing length and number of sex comb teeth in males, was tested in natural conditions. Males collected in copula were significantly larger than those collected as a single, while no difference in mean number of sex comb teeth between copulating and single males was observed. On the other hand, single males had greater asymmetry both for wing length and number of sex comb teeth than their mating counterparts. It looks like that symmetry of these bilateral traits also may play a role in sexual selection in this dipteran species in nature.

The diagnosis of Androgenic Deficiency of the Aging Male and the paths of male sexual desire

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Lucas Tramontano

2015-06-01

Full Text Available This article discusses the diagnosis of Androgenic Deficiency of the Aging Male (ADAM and the controversies and disputes over it, based on the re-medicalization of sexuality. The analysis is based on interviews with urologists and endocrinologists, and the different approaches of these two medical specialties elucidate divergent conceptions of body and sexuality present in the biomedical knowledge, and the struggle for hegemony in the scientific field. By comparing the meanings attributed to ADAM and to another male sexual dysfunction, the Erectile Dysfunction (ED, we intend to reflect about the difficulties inherent in the biological reduction of sexuality and the reiteration of gender norms in the medical discourse concerning the male body and sexuality.

Normal male childhood and adolescent sexual interactions: implications for sexual orientation of the individual with intersex.

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Lee, Peter A; Houk, Christopher P

2005-03-01

Data provided by 24 adult men, 20 heterosexual and four homosexual, concerning parental, religious, geographic and explicit sexual innuendos, comments and childhood experiences are presented and discussed in an attempt to consider some of the multiple factors impacting the development of sexual orientation. All of the study subjects were normally developed males and were presumed to have been exposed to normal male levels of androgens prenatally. Since the experiences and perceptions reported are conditioned by a unique social environment that has been superimposed on a normal male typical prenatal CNS differentiation, the experiences of these men suggest that affirmation of masculinity, and openness in the realm of social and sexual interaction, may enhance the formation of a heterosexual orientation. Conversely, sexually explicit feedback with critical implications occurred commonly among the homosexual men, which they interpreted as implying an insufficient masculinity. Both innate factors and social influences impact sexual orientation; in some instances males appear to have been homosexual from early childhood onward, while in other cases there appears to have been some degree of conditioning and choice in sexual orientation. Regarding the intersexed male, this suggests that social interactions, particularly those provided by parents, have a major influence on the development of sexual orientation in the child, while all persons involved in these children's lives and particularly those who nurture must be prepared for any sexual orientation that develops.

Sexual harassment in the context of double male dominance

NARCIS (Netherlands)

de Haas, S.; Timmerman, M.C.

2010-01-01

It has been suggested that numerically male-dominated workplaces propagate cultural norms that support sexual bravado, sexual posturing, and the denigration of feminine behaviour (Sbraga O'Donohue, 2000). These cultural norms are features of normative male dominance, which have been shown to

Administration of an oxytocin receptor antagonist attenuates sexual motivation in male rats.

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Blitzer, D S; Wells, T E; Hawley, W R

2017-08-01

In male rats, oxytocin impacts both sexual arousal and certain types of consummatory sexual behaviors. However, the role of oxytocin in the motivational aspects of sexual behavior has received limited attention. Given the role that oxytocin signaling plays in consummatory sexual behaviors, it was hypothesized that pharmacological attenuation of oxytocin signaling would reduce sexual motivation in male rats. Sexually experienced Long-Evans male rats were administered either an oxytocin receptor antagonist (L368,899 hydrochloride; 1mg/kg) or vehicle control into the intraperitoneal cavity 40min prior to placement into the center chamber of a three-chambered arena designed to assess sexual motivation. During the 20-minute test, a sexually experienced stimulus male rat and a sexually receptive stimulus female rat were separately confined to smaller chambers that were attached to the larger end chambers of the arena. However, physical contact between test and stimulus rats was prevented by perforated dividers. Immediately following the sexual motivation test, test male rats were placed with a sexually receptive female to examine consummatory sexual behaviors. Although both drug and vehicle treated rats exhibited a preference for the female, treatment with an oxytocin receptor antagonist decreased the amount of time spent with the female. There were no differences between drug and vehicle treated rats in either general activity, exploratory behaviors, the amount of time spent near the stimulus male rat, or consummatory sexual behaviors. Extending previous findings, these results indicate that oxytocin receptors are involved in sexual motivation in male rats. Copyright © 2017 Elsevier Inc. All rights reserved.

Prostate response to prolactin in sexually active male rats

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Garcia Luis I

2006-05-01

Full Text Available Abstract Background The prostate is a key gland in the sexual physiology of male mammals. Its sensitivity to steroid hormones is widely known, but its response to prolactin is still poorly known. Previous studies have shown a correlation between sexual behaviour, prolactin release and prostate physiology. Thus, here we used the sexual behaviour of male rats as a model for studying this correlation. Hence, we developed experimental paradigms to determine the influence of prolactin on sexual behaviour and prostate organization of male rats. Methods In addition to sexual behaviour recordings, we developed the ELISA procedure to quantify the serum level of prolactin, and the hematoxilin-eosin technique for analysis of the histological organization of the prostate. Also, different experimental manipulations were carried out; they included pituitary grafts, and haloperidol and ovine prolactin treatments. Data were analyzed with a One way ANOVA followed by post hoc Dunnet test if required. Results Data showed that male prolactin has a basal level with two peaks at the light-dark-light transitions. Consecutive ejaculations increased serum prolactin after the first ejaculation, which reached the highest level after the second, and started to decrease after the third ejaculation. These normal levels of prolactin did not induce any change at the prostate tissue. However, treatments for constant elevations of serum prolactin decreased sexual potency and increased the weight of the gland, the alveoli area and the epithelial cell height. Treatments for transient elevation of serum prolactin did not affect the sexual behaviour of males, but triggered these significant effects mainly at the ventral prostate. Conclusion The prostate is a sexual gland that responds to prolactin. Mating-induced prolactin release is required during sexual encounters to activate the epithelial cells in the gland. Here we saw a precise mechanism controlling the release of prolactin

Sexual Violence Among Male Inmates.

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Hilinski-Rosick, Carly M; Freiburger, Tina L

2018-04-01

Inmate misconduct has been a widely studied topic for many decades. General studies of misconduct have found that there are certain factors that contribute to misconduct, including age, gender, sentence length, and facility type. Few studies, however, have examined the factors predicting sexual offenses in a prison conduct. Although many studies of victims of sexual offenses in prison have been conducted, there is a lack of studies examining the perpetrators of prison sexual violence. The current study attempted to expand this body of literature by examining the correlates of sexual misconduct among a sample of male inmates incarcerated in the state of North Carolina during 2010. Deprivation and importation theories of inmate behavior were used to guide the analysis, and measures of deprivation and importation factors were both included in the analytical models. Findings indicate that Black, nonmarried, younger inmates, who had more previous incarcerations and had been incarcerated longer, had greater odds of having a sexual infraction. Additional findings, as well as policy implications, are discussed.

Nice guys finish last: same-sex sexual behavior and pairing success in male budgerigars

OpenAIRE

Puya Abbassi; Nancy Tyler Burley

2012-01-01

In budgerigars (Melopsittacus undulatus), a social parrot in which females are socially dominant, males of all ages engage in a set of behaviors with other males that closely resembles the repertoire used in heterosexual courtship. One adaptive hypothesis for this tendency, the "courtship practice hypothesis," posits that males with greater experience in same-sex activities develop superior skills that increase their courtship success with females. To test this hypothesis, we measured individ...

Sexual and Natural Selection Both Influence Male Genital Evolution

OpenAIRE

House, Clarissa M.; Lewis, Zenobia; Hodgson, Dave J.; Wedell, Nina; Sharma, Manmohan D.; Hunt, John; Hosken, David J.

2013-01-01

Rapid and divergent evolution of male genital morphology is a conspicuous and general pattern across internally fertilizing animals. Rapid genital evolution is thought to be the result of sexual selection, and the role of natural selection in genital evolution remains controversial. However, natural and sexual selection are believed to act antagonistically on male genital form. We conducted an experimental evolution study to investigate the combined effects of natural and sexual selection on ...

Epidemiology of sexual dysfunction in the male population.

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Beutel, M E; Weidner, W; Brähler, E

2006-08-01

Sexual dysfunctions have found an increasing attention in recent epidemiological studies of the ageing male. The purpose of this paper is to review the prevalence of sexual dysfunctions and risk factors based on community samples. Studies have not only demonstrated a strong age-related incline of erectile dysfunction (ED), but also of ejaculatory and orgasmic disorders (particularly a reduced or absent ejaculation). Despite a declining sexual desire, sexual interest remains present in old age. Lower urinary tract symptoms have been identified as strong risk factors for ED along with cardiovascular, metabolic, psychiatric disorders and lifestyle factors. The wide range of prevalence rate estimates is likely because of different definitions and criteria of sexual dysfunctions. More research is needed on other dysfunctions besides ED and on the partner relationship as a major determinant of sexual activity and satisfaction. The interrelationship between risk factors calls for interdisciplinary prevention and treatment approaches. As disability-free life expectancy keeps increasing, the need to identify, adequately assess and treat male sexual dysfunction as an important impediment to quality of life most likely will become even more pressing.

The role of protein in the sexual behaviour of males of Ceratitis capitata (Diptera: Tephritidae: mating success, copula duration and number of copulations

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Iara Sordi Joachim-Bravo

2009-09-01

Full Text Available In this paper, we investigated the influence of protein ingestion during the early adult phase on the sexual behavior of males of Ceratitis capitata (Wiedemann, 1824. The following parameters were evaluated: mating success (ability to be chosen by females, number of copulations, and copula duration. Experiments were carried out using a fifteen-year old laboratory lineage with the occasional introduction of wild flies. Two groups of adult males fed a high-protein diet during their larval phase were given either a high-protein diet (based on Brewer's yeast, concentration = 6.5 g/100 ml or a no-protein diet. Both groups of males were exposed to females fed either a high-protein diet or a no-protein diet and were subsequently evaluated for the parameters listed above. All experiments were conducted at 25ºC, 70% R.H. and with a photoperiod of L12:D12. The number of copulations was the only parameter affected by adult diet. Males fed a high-protein diet and exposed to females fed a no-protein diet had a greater number of copulations compared with males fed a no-protein diet.

Male Survivors of Sexual Abuse: Becoming Gender-Sensitive and Trauma-Informed

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Jennifer Elkins

2017-09-01

Full Text Available While there is a wide body of literature examining the behavioral, emotional, and social consequences associated with being sexually abused, comparatively few studies have focused on males. Sexual abuse victimization among males remains largely under-reported, under-treated, and under-recognized by researchers, practitioners, and the public. Researchers trying to clarify why sexual abuse in males has been overlooked point to prevailing cultural norms, myths, assumptions, stigma, and biases about masculinity. Consequently, there is often an assumption that males are not negatively affected by sexual abuse. Drawing extensively from the literature, this article provides a critical review of: (1 the nature, experience and impact of sexual abuse victimization for males; and (2 the multidimensional processes that promote and inhibit resilient outcomes. It concludes with a discussion of trauma-informed and gender-responsive recommendations and future directions for social work practice, policy, and research.

Intimacy and sexual risk behaviour in serodiscordant male couples.

Science.gov (United States)

Remien, R H; Carballo-Diéguez, A; Wagner, G

1995-01-01

Several studies have demonstrated individual-level determinants of HIV sexual risk behaviour. Very little research has been conducted to identify couple-level factors associated with unsafe sexual behaviour. As part of a three-year study of more than 100 serodiscordant male couples, we conducted an in-depth qualitative study of 15 Latino and non-Latino male couples via focus groups and a follow-up telephone survey. We identified the sexual risk behaviour that occurs in these male couples, their perceptions of susceptibility for HIV transmission, and numerous couple-level and intrapsychic factors associated with their risk behaviour. We also describe the challenges confronted by these couples and barriers to emotional intimacy and couple satisfaction. Finally, we provide suggestions for ways of intervening to facilitate improved couple functioning, pleasure, satisfaction, and communication, and ways of reducing sexual risk behaviour without loss of emotional intimacy.

The control of male sexual responses.

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Courtois, Frédérique; Carrier, Serge; Charvier, Kathleen; Guertin, Pierre A; Journel, Nicolas Morel

2013-01-01

Male sexual responses are reflexes mediated by the spinal cord and modulated by neural circuitries involving both the peripheral and central nervous system. While the brain interact with the reflexes to allow perception of sexual sensations and to exert excitatory or inhibitory influences, penile reflexes can occur despite complete transections of the spinal cord, as demonstrated by the reviewed animal studies on spinalization and human studies on spinal cord injury. Neurophysiological and neuropharmacological substrates of the male sexual responses will be discussed in this review, starting with the spinal mediation of erection and its underlying mechanism with nitric oxide (NO), followed by the description of the ejaculation process, its neural mediation and its coordination by the spinal generator of ejaculation (SGE), followed by the occurrence of climax as a multisegmental sympathetic reflex discharge. Brain modulation of these reflexes will be discussed through neurophysiological evidence involving structures such as the medial preoptic area of hypothalamus (MPOA), the paraventricular nucleus (PVN), the periaqueductal gray (PAG), and the nucleus para-gigantocellularis (nPGI), and through neuropharmacological evidence involving neurotransmitters such as serotonin (5-HT), dopamine and oxytocin. The pharmacological developments based on these mechanisms to treat male sexual dysfunctions will complete this review, including phosphodiesterase (PDE-5) inhibitors and intracavernous injections (ICI) for the treatment of erectile dysfunctions (ED), selective serotonin reuptake inhibitor (SSRI) for the treatment of premature ejaculation, and cholinesterase inhibitors as well as alpha adrenergic drugs for the treatment of anejaculation and retrograde ejaculation. Evidence from spinal cord injured studies will be highlighted upon each step.

Diploid male dynamics under different numbers of sexual alleles and male dispersal abilities.

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Faria, Luiz R R; Soares, Elaine Della Giustina; Carmo, Eduardo do; Oliveira, Paulo Murilo Castro de

2016-09-01

Insects in the order Hymenoptera (bees, wasps and ants) present an haplodiploid system of sexual determination in which fertilized eggs become females and unfertilized eggs males. Under single locus complementary sex-determination (sl-CSD) system, the sex of a specimen depends on the alleles at a single locus: when diploid, an individual will be a female if heterozygous and male if homozygous. Significant diploid male (DM) production may drive a population to an extinction scenario called "diploid male vortex". We aimed at studying the dynamics of populations of a sl-CSD organism under several combinations of two parameters: male flight abilities and number of sexual alleles. In these simulations, we evaluated the frequency of DM and a genetic diversity measure over 10,000 generations. The number of sexual alleles varied from 10 to 100 and, at each generation, a male offspring might fly to another random site within a varying radius R. Two main results emerge from our simulations: (i) the number of DM depends more on male flight radius than on the number of alleles; (ii) in large geographic regions, the effect of males flight radius on the allelic diversity turns out much less pronounced than in small regions. In other words, small regions where inbreeding normally appears recover genetic diversity due to large flight radii. These results may be particularly relevant when considering the population dynamics of species with increasingly limited dispersal ability (e.g., forest-dependent species of euglossine bees in fragmented landscapes).

Darcin: a male pheromone that stimulates female memory and sexual attraction to an individual male's odour

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McLean Lynn

2010-06-01

Full Text Available Abstract Background Among invertebrates, specific pheromones elicit inherent (fixed behavioural responses to coordinate social behaviours such as sexual recognition and attraction. By contrast, the much more complex social odours of mammals provide a broad range of information about the individual owner and stimulate individual-specific responses that are modulated by learning. How do mammals use such odours to coordinate important social interactions such as sexual attraction while allowing for individual-specific choice? We hypothesized that male mouse urine contains a specific pheromonal component that invokes inherent sexual attraction to the scent and which also stimulates female memory and conditions sexual attraction to the airborne odours of an individual scent owner associated with this pheromone. Results Using wild-stock house mice to ensure natural responses that generalize across individual genomes, we identify a single atypical male-specific major urinary protein (MUP of mass 18893Da that invokes a female's inherent sexual attraction to male compared to female urinary scent. Attraction to this protein pheromone, which we named darcin, was as strong as the attraction to intact male urine. Importantly, contact with darcin also stimulated a strong learned attraction to the associated airborne urinary odour of an individual male, such that, subsequently, females were attracted to the airborne scent of that specific individual but not to that of other males. Conclusions This involatile protein is a mammalian male sex pheromone that stimulates a flexible response to individual-specific odours through associative learning and memory, allowing female sexual attraction to be inherent but selective towards particular males. This 'darcin effect' offers a new system to investigate the neural basis of individual-specific memories in the brain and give new insights into the regulation of behaviour in complex social mammals. See associated

Darcin: a male pheromone that stimulates female memory and sexual attraction to an individual male's odour.

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Roberts, Sarah A; Simpson, Deborah M; Armstrong, Stuart D; Davidson, Amanda J; Robertson, Duncan H; McLean, Lynn; Beynon, Robert J; Hurst, Jane L

2010-06-03

Among invertebrates, specific pheromones elicit inherent (fixed) behavioural responses to coordinate social behaviours such as sexual recognition and attraction. By contrast, the much more complex social odours of mammals provide a broad range of information about the individual owner and stimulate individual-specific responses that are modulated by learning. How do mammals use such odours to coordinate important social interactions such as sexual attraction while allowing for individual-specific choice? We hypothesized that male mouse urine contains a specific pheromonal component that invokes inherent sexual attraction to the scent and which also stimulates female memory and conditions sexual attraction to the airborne odours of an individual scent owner associated with this pheromone. Using wild-stock house mice to ensure natural responses that generalize across individual genomes, we identify a single atypical male-specific major urinary protein (MUP) of mass 18893Da that invokes a female's inherent sexual attraction to male compared to female urinary scent. Attraction to this protein pheromone, which we named darcin, was as strong as the attraction to intact male urine. Importantly, contact with darcin also stimulated a strong learned attraction to the associated airborne urinary odour of an individual male, such that, subsequently, females were attracted to the airborne scent of that specific individual but not to that of other males. This involatile protein is a mammalian male sex pheromone that stimulates a flexible response to individual-specific odours through associative learning and memory, allowing female sexual attraction to be inherent but selective towards particular males. This 'darcin effect' offers a new system to investigate the neural basis of individual-specific memories in the brain and give new insights into the regulation of behaviour in complex social mammals.See associated Commentary http://www.biomedcentral.com/1741-7007/8/71.

Sociosexual attitudes and dyadic sexual desire independently predict women's preferences for male vocal masculinity.

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O'Connor, Jillian J M; Jones, Benedict C; Fraccaro, Paul J; Tigue, Cara C; Pisanski, Katarzyna; Feinberg, David R

2014-10-01

Research suggests that the desire to behave sexually with a partner (dyadic sexual desire) may reflect desire for intimacy whereas solitary sexual desire may reflect pleasure seeking motivations more generally. Because direct reproductive success can only be increased with a sexual partner, we tested whether dyadic sexual desire was a better predictor of women's preferences for lower pitched men's voices (a marker of relatively high reproductive success) than was solitary sexual desire. In Study 1, women (N = 95) with higher dyadic sexual desire scores on the Sexual Desire Inventory-2 preferred masculinized male voices more than did women with lower dyadic sexual desire scores. We did not find a significant relationship between women's vocal masculinity preferences and their solitary sexual desire scores. In Study 2, we tested whether the relationship between voice preferences and dyadic sexual desire scores was related to differences in sociosexual orientation. Women (N = 80) with more positive attitudes towards uncommitted sex had stronger vocal masculinity preferences regardless of whether men's attractiveness was judged for short-term or long-term relationships. Independent of the effect of sociosexual attitudes, dyadic sexual desire positively predicted women's masculinity preferences when assessing men's attractiveness for short-term but not long-term relationships. These effects were independent of women's own relationship status and hormonal contraceptive use. Our results provide further evidence that women's mate preferences may independently reflect individual differences in both sexual desire and openness to short-term relationships, potentially with the ultimate function of maximizing the fitness benefits of women's mate choices.

The role of estrogen G-protein coupled receptor 30 (GPR30) and sexual experience in sexual incentive motivation in male rats.

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Hawley, W R; Battista, C; Divack, S R; Morales Núñez, N B

2017-08-01

Male rats exhibit reductions in sexual motivation following systemic administration of drugs that inhibit the conversion of testosterone to estrogen, which indicates that estrogen signaling plays a role in male rat sexual motivation. Given that estrogen G-protein coupled receptor 30 (GPR30) is expressed in brain areas that are important for male sexual behaviors and endocrine function, the primary aim of the current study was to examine the role that GPR30 plays in sexual motivation in both sexually naïve and sexually experienced male rats. Following the final treatment with either a GPR30 antagonist (G-15) or vehicle control, male rats were placed into the center chamber of a larger three-chambered testing arena that was designed to assess sexual incentive motivation. A sexually receptive stimulus female rat and a stimulus male rat were individually confined to one of the two smaller chambers that were each separated by a perforated partition from the larger end chambers, which test rats had access to. Relative to vehicle treated rats, male rats treated with G-15 exhibited a reduction in the percentage of time spent in the vicinity of a sexually receptive female rat. Although G-15 reduced sexual incentive motivation independent of sexual experience, only sexually-naïve rats treated with G-15 did not exhibit a preference for the sexually receptive stimulus female rat. Collectively, these results indicate that interference with estrogen signaling at GPR30 reduces sexual motivation and that the lack of preference for a sexually receptive female rat over a male rat following G-15 treatment is abrogated by previous sexual experience. Copyright © 2017 Elsevier Inc. All rights reserved.

International Spinal Cord Injury Male Sexual Function Basic Data Set

DEFF Research Database (Denmark)

Alexander, M S; Biering-Sørensen, F; Elliott, S

2011-01-01

To create the International Spinal Cord Injury (SCI) Male Sexual Function Basic Data Set within the International SCI Data Sets.......To create the International Spinal Cord Injury (SCI) Male Sexual Function Basic Data Set within the International SCI Data Sets....

Knowledge of sexually transmitted diseases and sexual behaviours among Malaysian male youths.

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Awang, Halimah; Wong, Li Ping; Jani, Rohana; Low, Wah Yun

2014-03-01

This study examines the knowledge of sexually transmitted diseases (STDs) among male youths in Malaysia. A self-administered survey was carried out on a sample of 952 never-married males aged 15-24 years. The respondents were asked about their knowledge of STDs, how these diseases get transmitted and their sexual behaviours. The data showed that 92% of the respondents knew of at least one STD (syphilis, gonorrhoea, chlamydia, herpes, genital warts, yeast infection, trichomoniasis or HIV/AIDS). About 95% of them knew of at least one method of STD transmission. Urban and tertiary-educated male youths showed a substantially higher proportion of awareness of STDs and transmission methods compared with their rural and less-educated counterparts. The data also indicated that 10% of the study sample admitted to having had sexual experiences. There were still a large proportion of the respondents who were not aware of STDs other than syphilis and HIV/AIDS and the means of transmission, such as multiple sex partners, including those who claimed to be sexually active. Thus there is a need for more concerted efforts to disseminate information on STDs and transmission methods to a wider audience in Malaysia, especially youths in rural areas.

Male partners of women with provoked vestibulodynia: attributions for pain and their implications for dyadic adjustment, sexual satisfaction, and psychological distress.

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Jodoin, Mélanie; Bergeron, Sophie; Khalifé, Samir; Dupuis, Marie-José; Desrochers, Geneviève; Leclerc, Bianca

2008-12-01

Provoked vestibulodynia is a female genital pain condition that results in sexual dysfunction and impacts negatively on the couple. Although patients' causal attributions have been linked to worse psychosexual outcomes, no study has documented the male partners' perspective of this distressing problem and its potential influence on their psychosexual adaptation. To identify whether male partners' attributions for vestibulodynia are possible predictors of their dyadic adjustment, sexual functioning, sexual satisfaction, and psychological distress, as well as of women's pain and sexual functioning. Thirty-eight women with vestibulodynia first completed measures of pain intensity and sexual functioning. Male partners responded to mailed questionnaires assessing their own attributions for genital pain as well as their psychological distress, relationship adjustment, sexual functioning, and sexual satisfaction. Women completed the McGill-Melzack Pain Questionnaire (MPQ) and the Female Sexual Function Index (FSFI). Attributions of male partners were measured using an adapted version of the Attributional Style Questionnaire (ASQ)-Partner Version. Men also filled out the Brief Symptom Inventory (BSI), the Dyadic Adjustment Scale (DAS), the Sexual History Form (SHF), and the Global Measure of Sexual Satisfaction (GMSEX). All four negative attribution dimensions and higher levels of women's pain intensity successfully predicted increased psychological distress in male partners. Higher levels of both internal and global attributions were associated with men's poorer dyadic adjustment, whereas global and stable attributions were related to their lower sexual satisfaction. Attributions failed to significantly predict sexual functioning in male partners and women's pain and sexual functioning. Evaluation and treatment of sexual pain problems should involve both partners and should explore the role of negative attributions.

Male adolescent sexual offenders: exhibitionism and obscene phone calls.

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Saunders, E B; Awad, G A

1991-01-01

Clinical assessment of 19 male adolescent sexual offenders who had committed exhibitionism or telephone scatologia showed that the majority were maladjusted, had committed numerous sexual offenses and came from multi-problem families. Several of them appeared to be sexually deviant, although they did not meet DSM-III-R criteria for a diagnosis of paraphilia. Anti-social traits, sexual deviance in the family, homosexual conflicts, repressed sexuality and sexual deviance were considered to be contributory factors.

A profile of sexually active male adolescent high school students in Lima, Peru

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Chirinos Jesús L.

2000-01-01

Full Text Available To document knowledge and attitudes regarding sexuality and sexual practices of male adolescent high school students in Lima, Peru, a self-administered, anonymous survey was completed by 991 male adolescents aged 12-19 as part of a School-Based Sex Education Intervention model. Questions concerned sociodemographic information; family characteristics; personal activities; knowledge and attitudes regarding sexuality; sexual experience; and contraceptive use. Knowledge related to sexuality was limited. Males tended to mainly discuss sexuality with their male peers (49.8%. Attitudes towards sexual activity and condom use were largely positive, although some males expressed ambivalent feelings towards the latter. Of the sample, 43% had ever had sex; age at first sexual intercourse was 13 years. While 88% of the sample would use condoms, 74% also gave reasons for not using them. Sexual activity was related to age, ever having repeated a grade, living with only one parent or in a mixed family, activities such as going to parties, use of alcohol, tobacco, and drugs, and viewing pornographic videos or magazines. Many male adolescents were at risk of causing an unintended pregnancy or acquiring an STD.

Child Sexual Abuse and HIV-Related Substance Use and Sexual Risk Across the Life Course Among Males and Females.

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Scheidell, Joy D; Kumar, Pritika C; Campion, Taylor; Quinn, Kelly; Beharie, Nisha; McGorray, Susan P; Khan, Maria R

2017-07-01

Child sexual abuse is associated with substance use and sexual risk behaviors during adolescence and adulthood, but no known studies have documented associations across the life course in a nationally representative U.S. We used the National Longitudinal Study of Adolescent to Adult Health to measure associations between child sexual abuse and substance use and sexual risk behaviors during adolescence, young adulthood, and adulthood among males and females (n = 11,820). Approximately 10% of females and 7% of males reported child sexual abuse. Associations with substance use were strongest during adolescence and lessened over time. Increased odds of sexual risk among those with a history of child sexual abuse remained consistent through the life course. Significant gender differences existed for some associations (e.g., adulthood multiple partners: males adjusted odds ratio (AOR) = 1.73, 95%CI:1.18, 2.53; females AOR = 1.11, 95%CI:0.79, 1.56). Trauma-informed prevention interventions should address child sexual abuse among both males and females to prevent substance use and sexual risk behavior throughout the life course.

Male mice ultrasonic vocalizations enhance female sexual approach and hypothalamic kisspeptin neuron activity.

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Asaba, Akari; Osakada, Takuya; Touhara, Kazushige; Kato, Masahiro; Mogi, Kazutaka; Kikusui, Takefumi

2017-08-01

Vocal communication in animals is important for ensuring reproductive success. Male mice emit song-like "ultrasonic vocalizations (USVs)" when they encounter female mice, and females show approach to the USVs. However, it is unclear whether USVs of male mice trigger female behavioral and endocrine responses in reproduction. In this study, we first investigated the relationship between the number of deliveries in breeding pairs for 4months and USVs syllables emitted from those paired males during 3min of sexual encounter with unfamiliar female mice. There was a positive correlation between these two indices, which suggests that breeding pairs in which males could emit USVs more frequently had more offspring. Further, we examined the effect of USVs of male mice on female sexual behavior. Female mice showed more approach behavior towards vocalizing males than devocalized males. Finally, to determine whether USVs of male mice could activate the neural system governing reproductive function in female mice, the activation of kisspeptin neurons, key neurons to drive gonadotropin-releasing hormone neurons in the hypothalamus, was examined using dual-label immunocytochemistry with cAMP response element-binding protein phosphorylation (pCREB). In the arcuate nucleus (Arc), the number of kisspeptin neurons expressing pCREB significantly increased after exposure to USVs of male as compared with noise exposure group. In conclusion, our results suggest that USVs of male mice promote fertility in female mice by activating both their approaching behavior and central kisspeptin neurons. Copyright © 2017 Elsevier Inc. All rights reserved.

Parental influences of sexual risk among urban African American adolescent males.

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Harris, Allyssa L; Sutherland, Melissa A; Hutchinson, M Katherine

2013-06-01

This study examined the influence of parental marital status, parent-child sexual communication, parent-child closeness on the HIV-related knowledge, safer-sex intentions, and behaviors of late adolescent urban African American males. The study employed a cross-sectional design with retrospective recall of salient parental influences and behaviors. Data were collected via paper-and-pencil questionnaire from 134 late adolescent African American males, 18 to 22 years of age, recruited from urban communities in and around Boston, Massachusetts. Data were analyzed using bivariate correlations, paired t tests, and regression modeling. Young men reported greater amounts of sexual communication with mothers than fathers (p fathers (p permissive sexual attitudes (p father-son communication and develop strategies to help parents communicate effectively with sons. Evidence has shown that African American adolescent males are more likely to engage in high-risk sexual behaviors. Understanding the sexual risk communication between African American adolescent males and their parents is important to developing strategies in reducing sexual risk behavior. © 2013 Sigma Theta Tau International.

Novel host plant leads to the loss of sexual dimorphism in a sexually selected male weapon.

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Allen, Pablo E; Miller, Christine W

2017-08-16

In this time of massive global change, species are now frequently interacting with novel players. Greater insight into the impact of these novel interactions on traits linked to fitness is essential, because effects on these traits can hinder population existence or promote rapid adaptation. Sexually selected weapons and ornaments frequently influence fitness and often have heightened condition-dependence in response to nutrition. Condition-dependence in response to different ecological conditions, a form of developmental plasticity, may be responsible for much of the intraspecific variation in sexually selected ornaments and weapons in wild populations. Here we examined the consequences of developing on a novel plant for the expression of size and shape in the leaf-footed cactus bug Narnia femorata (Hemiptera: Coreidae). The males of this species possess enlarged, sexually dimorphic femurs on their hind legs. These legs are used as weapons in male-male contests. Females are typically larger in overall body size. Our study revealed that developing upon a novel host can lead to pronounced phenotypically plastic change in sexually dimorphic traits. Male hind femurs were greatly impacted by the novel diet to the extent that the sexual dimorphism in hind femurs was lost. Further, dimorphism in body size increased, as males became tiny adults while females better maintained their body size. These patterns underscore the complex effects that novel species interactions may have on sexual phenotypes. © 2017 The Author(s).

Examining the development and sexual behavior of adolescent males.

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Ott, Mary A

2010-04-01

A careful examination of young men's sexuality by health professionals in pediatrics, primary care, and reproductive health is foundational to adolescent male sexual health and healthy development. Through a review of existing published data, this article provides background and a developmental framework for sexual health services for adolescent boys. The article first defines and provides an overview of adolescent boys' sexual health, and then discusses developmentally focused research on the following topics: (1) early romantic relationships and the evolution of power and influence within these relationships; (2) developmental "readiness" for sex and curiosity; (3) boys' need for closeness and intimacy; (4) adopting codes of masculinity; (5) boys' communicating about sex; and (6) contextual influences from peers, families, and providers. This article concludes by examining the implications of these data for sexual health promotion efforts for adolescent males, including human papillomavirus vaccination.

[Perinatal clomiphene citrate treatment changes sexual orientations of male mice].

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He, Feng-Qin; Zhang, Heng-Rui

2013-10-01

Perinatal period and adolescence are critical for brain development, which is the biological basis of an individual's sexual orientation and sexual behavior. In this study, animals were divided into two groups and their sexual orientations were observed: one group experienced drug treatments during the perinatal period, and the other group was castrated at puberty. The results showed that estradiol treatment had no effect on mature male offspring's sexual orientations, but 9 days and 14 days of clomiphene citrate treatment significantly increased the chance of homosexuality and effeminized behavior. In addition, the sexual orientation of mature normal male offspring, which were castrated when they were 21 days old,was not significant different from the control animals. These findings suggest that the inhibition of perinatal estrogen activities could suppress individual male-typical responses, enhance female-typical responses and induce homosexual orientations. Moreover, the masculinizing effects of estrogen were more obvious during perinatal period than adolescence.

Sexually antagonistic selection in human male homosexuality.

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Andrea Camperio Ciani

Full Text Available Several lines of evidence indicate the existence of genetic factors influencing male homosexuality and bisexuality. In spite of its relatively low frequency, the stable permanence in all human populations of this apparently detrimental trait constitutes a puzzling 'Darwinian paradox'. Furthermore, several studies have pointed out relevant asymmetries in the distribution of both male homosexuality and of female fecundity in the parental lines of homosexual vs. heterosexual males. A number of hypotheses have attempted to give an evolutionary explanation for the long-standing persistence of this trait, and for its asymmetric distribution in family lines; however a satisfactory understanding of the population genetics of male homosexuality is lacking at present. We perform a systematic mathematical analysis of the propagation and equilibrium of the putative genetic factors for male homosexuality in the population, based on the selection equation for one or two diallelic loci and Bayesian statistics for pedigree investigation. We show that only the two-locus genetic model with at least one locus on the X chromosome, and in which gene expression is sexually antagonistic (increasing female fitness but decreasing male fitness, accounts for all known empirical data. Our results help clarify the basic evolutionary dynamics of male homosexuality, establishing this as a clearly ascertained sexually antagonistic human trait.

Chronic fluoxetine inhibits sexual behavior in the male rat: reversal with oxytocin.

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Cantor, J M; Binik, Y M; Pfaus, J G

1999-06-01

Selective serotonin reuptake inhibitors, used widely in the treatment of depression, progressively inhibit sexual orgasm in many patients and induce a transient inhibition of sexual desire. We attempted to model the effects of these drugs in sexually experienced male rats during tests of copulation in bilevel chambers. These chambers allow the study of both appetitive and consummatory sexual responses of male rats. Males were treated daily with fluoxetine hydrochloride (0, 1, 5, or 10 mg/kg) and tested for sexual behavior with receptive females at 4-day intervals. Rats were treated with oxytocin (200 ng/kg) or saline after ejaculations had decreased. Fluoxetine decreased ejaculatory responses of male rats in a dose- and time-dependent fashion, but left the copulatory efficiency of the males intact. In contrast, conditioned level changing, a measure of appetitive sexual excitement, was inhibited following acute and chronic treatment with 10 mg/kg, although tolerance may have developed to the effect of 5 mg/kg. Subsequent administration of oxytocin restored the ejaculatory response but not the measure of sexual excitement to baseline levels. The reversal by oxytocin of the fluoxetine-induced deficit in ejaculations is consistent with the hypothesis that serotonin suppresses ejaculatory mechanisms by interrupting the action of oxytocin, which normally accompanies sexual behavior. Co-administration of oxytocin may help to alleviate the predominant sexual side effect of serotonin reuptake blockers.

Prevalence of consensual male-male sex and sexual violence, and associations with HIV in South Africa: a population-based cross-sectional study.

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Kristin L Dunkle

Full Text Available In sub-Saharan Africa the population prevalence of men who have sex with men (MSM is unknown, as is the population prevalence of male-on-male sexual violence, and whether male-on-male sexual violence may relate to HIV risk. This paper describes lifetime prevalence of consensual male-male sexual behavior and male-on-male sexual violence (victimization and perpetration in two South African provinces, socio-demographic factors associated with these experiences, and associations with HIV serostatus.In a cross-sectional study conducted in 2008, men aged 18-49 y from randomly selected households in the Eastern Cape and KwaZulu-Natal provinces provided anonymous survey data and dried blood spots for HIV serostatus assessment. Interviews were completed in 1,737 of 2,298 (75.6% of enumerated and eligible households. From these households, 1,705 men (97.1% provided data on lifetime history of same-sex experiences, and 1,220 (70.2% also provided dried blood spots for HIV testing. 5.4% (n = 92 of participants reported a lifetime history of any consensual sexual activity with another man; 9.6% (n = 164 reported any sexual victimization by a man, and 3.0% (n = 51 reported perpetrating sexual violence against another man. 85.0% (n = 79 of men with a history of consensual sex with men reported having a current female partner, and 27.7% (n = 26 reported having a current male partner. Of the latter, 80.6% (n = 21/26 also reported having a female partner. Men reporting a history of consensual male-male sexual behavior are more likely to have been a victim of male-on-male sexual violence (adjusted odds ratio [aOR] = 7.24; 95% CI 4.26-12.3, and to have perpetrated sexual violence against another man (aOR = 3.10; 95% CI 1.22-7.90. Men reporting consensual oral/anal sex with a man were more likely to be HIV+ than men with no such history (aOR = 3.11; 95% CI 1.24-7.80. Men who had raped a man were more likely to be HIV+ than non

Exposure to odors of rivals enhances sexual motivation in male giant pandas.

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Xiaoxing Bian

Full Text Available Males will alter their mating behavior to cope with the presence of their competitors. Even exposure to odors from potential competitors can greatly increase male ejaculate expenditure in a variety of animals including insects, fishes, birds and rodents. Major efforts have been made to examine males' plastic responses to sperm competition and its fitness benefits. However, the effects of competitor absence on male's sexual motivation and behaviors remain unclear, which has been proposed to be one of the causes for the poor sexual performance of some captive mammals. This study revealed that sexual motivation can be greatly enhanced in captive male giant pandas (Ailuropoda melanoleuca by exposure to chemosensory cues from either one or three conspecifics males. It had been shown that potential rivals' odors increased males' chemosensory investigation behavior, as well as their observing, following and sniffing behaviors towards estrous females. Behaviors changed regardless of the number of rivals (one or three. Our results demonstrate the effects of potential competition on male giant pandas' sexual motivation and behavioral coping strategy. We anticipate that our research will provide a fresh insight into the mechanisms underlying poor sexual performance in male captive mammals, and valuable information for the practical management and ex situ conservation of endangered species.

Effects of testosterone on contractile properties of sexually dimorphic forelimb muscles in male bullfrogs (Rana catesbeiana, Shaw 1802

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Aaron R. Kampe

2013-07-01

This study examined the effects of testosterone (T on the contractile properties of two sexually dimorphic forelimb muscles and one non-dimorphic muscle in male bullfrogs (Rana catesbeiana, Shaw 1802. The dimorphic muscles in castrated males with testosterone replacement (T+ achieved higher forces and lower fatigability than did castrated males without replaced testosterone (T0 males, but the magnitude of the differences was low and many of the pair-wise comparisons of each muscle property were not statistically significant. However, when taken as a whole, the means of seven contractile properties varied in the directions expected of masculine values in T+ animals in the sexually dimorphic muscles. Moreover, these data, compared with previous data on male and female bullfrogs, show that values for T+ males are similar to normal males and are significantly different from females. The T0 males tended to be intermediate in character between T+ males and females, generally retaining masculine values. This suggests that the exposure of young males to T in their first breeding season produces a masculinizing effect on the sexually dimorphic muscles that is not reversed between breeding seasons when T levels are low. The relatively minor differences in contractile properties between T+ and T0 males may indicate that as circulating T levels rise during breeding season in normal males, contractile properties can be enhanced rapidly to maximal functional levels for breeding success.

Self-efficacy, male rape myth acceptance, and devaluation of emotions in sexual trauma sequelae: Findings from a sample of male veterans.

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Voller, Emily; Polusny, Melissa A; Noorbaloochi, Siamak; Street, Amy; Grill, Joseph; Murdoch, Maureen

2015-11-01

Sexual trauma is an understudied but regrettably significant problem among male Veterans. As in women, sexual trauma often results in serious mental health consequences for men. Therefore, to guide potential future interventions in this important group, we investigated associations among self-efficacy, male rape myth acceptance, devaluation of emotions, and psychiatric symptom severity after male sexual victimization. We collected data from 1,872 Gulf War era Veterans who applied for posttraumatic stress disorder (PTSD) disability benefits using standard mailed survey methods. The survey asked about history of childhood sexual abuse, sexual assault during the time of Gulf War I, and past-year sexual assault as well as Veterans' perceived self-efficacy, male rape myth acceptance, devaluation of emotions, PTSD, and depression symptoms. Structural equation modeling revealed that self-efficacy partially mediated the association between participants' sexual trauma history and psychiatric symptoms. Greater male rape myth acceptance and greater devaluation of emotions were directly associated with lower self-efficacy, but these beliefs did not moderate associations between sexual trauma and self-efficacy. In this population, sexual trauma, male rape myth acceptance, and devaluation of emotions were associated with lowered self-efficacy, which in turn was associated with more severe psychiatric symptoms. Implications for specific, trauma-focused treatment are discussed. (c) 2015 APA, all rights reserved).

Dopamine D5 receptor modulates male and female sexual behavior in mice.

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Kudwa, A E; Dominguez-Salazar, E; Cabrera, D M; Sibley, D R; Rissman, E F

2005-07-01

Dopamine exerts its actions through at least five receptor (DAR) isoforms. In female rats, D5 DAR may be involved in expression of sexual behavior. We used a D5 knockout (D5KO) mouse to assess the role of D5 DAR in mouse sexual behavior. Both sexes of D5KO mice are fertile and exhibit only minor disruptions in exploratory locomotion, startle, and prepulse inhibition responses. This study was conducted to characterize the sexual behavior of male and female D5KO mice relative to their WT littermates. Female WT and D5KO littermates were ovariectomized and given a series of sexual behavior tests after treatment with estradiol benzoate (EB) and progesterone (P). Once sexual performance was optimal the dopamine agonist, apomorphine (APO), was substituted for P. Male mice were observed in pair- and trio- sexual behavior tests. To assess whether the D5 DAR is involved in rewarding aspects of sexual behavior, WT and D5KO male mice were tested for conditioned place preference. Both WT and D5KO females can display receptivity after treatment with EB and P, but APO was only able to facilitate receptivity in EB-primed WT, not in D5KO, mice. Male D5KO mice display normal masculine sexual behavior in mating tests. In conditioned preference tests, WT males formed a conditioned preference for context associated with either intromissions alone or ejaculation as the unconditioned stimulus. In contrast, D5KO males only showed a place preference when ejaculation was paired with the context. In females, the D5 DAR is essential for the actions of dopamine on receptivity. In males, D5 DAR influences rewarding aspects of intromissions. Taken together, the work suggests that the D5 receptor mediates dopamine's action on sexual behavior in both sexes, perhaps via a reward pathway.

Sexual selection protects against extinction

OpenAIRE

Lumley, Alyson; Michalczyk, Lukasz; Kitson, James; Spurgin, Lewis; Morrison, Catriona; Godwin, Joanne; Dickinson, Matthew; Martin, Oliver; Emerson, Brent; Chapman, Tracey; Gage, Matthew

2015-01-01

Reproduction through sex carries substantial costs, mainly because only half of sexual adults produce offspring. It has been theorised that these costs could be countered if sex allows sexual selection to clear the universal fitness constraint of mutation load. Under sexual selection, competition between (usually) males, and mate choice by (usually) females create important intraspecific filters for reproductive success, so that only a subset of males gains paternity. If reproductive success ...

Risks and benefits of multiple sexual partnerships: beliefs of rural Nigerian adolescent males.

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Izugbara, Chimaraoke Otutubikey; Nwabuawele Modo, Felicia

2007-09-01

Drawing on interview data from rural Nigeria, the article explores male youth perceptions of the risks and benefits of multiple sexual partnerships. Participants associated having multiple sexual partners with several harmful health and nonhealth outcomes, including sexually transmitted infections, and frequently confirmed that the practice also bolsters their sense of maleness and boosts their acceptance and ranking among peers. Young males' involvement in multiple sexual partnerships should not be seen as always consequent on their ignorance of and/or indifference to the risks inherent in the behavior. It could also result from the integrality of the behavior to the social processes through which male youths validate their masculinity, mark their transition from boyhood to malehood, and configure their identities to gain acceptance into a local male peer community. Sexuality education curricula that ignore adolescents' understandings of the benefits of their sexual practices may not deliver expected objectives.

The Role of Pelvic Floor Muscles in Male Sexual Dysfunction and Pelvic Pain.

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Cohen, Deborah; Gonzalez, Joshua; Goldstein, Irwin

2016-01-01

Sexual function is essential to good health and well-being in men. The relationship between male sexual function, pelvic floor function, and pelvic pain is complex and only beginning to be appreciated. The objectives of the current review are to examine these complex relationships, and to demonstrate how pelvic floor physical therapy can potentially improve the treatment of various male sexual dysfunctions, including erectile dysfunction and dysfunction of ejaculation and orgasm. Contemporary data on pelvic floor anatomy and function as they relate to the treatment of various male sexual dysfunctions were reviewed. Examination of evidence supporting the association between the male pelvic floor and erectile dysfunction, ejaculatory/orgasmic dysfunction, and chronic prostatitis/chronic pelvic pain syndrome, respectively. Evidence suggests a close relationship between the pelvic floor and male sexual dysfunction and a potential therapeutic benefit from pelvic floor therapy for men who suffer from these conditions. Pelvic floor physical therapy is a necessary tool in a more comprehensive bio-neuromusculoskeletal-psychosocial approach to the treatment of male sexual dysfunction and pelvic pain. Copyright © 2016 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

Comparing Female and Male Perpetrators' Modus Operandi: Victims' Reports of Sexual Abuse.

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Kaufman, Keith L.; And Others

1995-01-01

Investigated similarities and differences in modus operandi of female and male child sexual abusers by comparing victims of female and male perpetrators. Females were more often involved with males in co-offender situations and were more likely to exploit victims. Males were more sexually invasive and more likely to use bribes to obtain victim…

Asymmetric forceps increase fighting success among males of similar size in the maritime earwig

Science.gov (United States)

Munoz, Nicole E.; Zink, Andrew G.

2012-01-01

Extreme asymmetric morphologies are hypothesized to serve an adaptive function that counteracts sexual selection for symmetry. However direct tests of function for asymmetries are lacking, particularly in the context of animal weapons. The weapon of the maritime earwig, Anisolabis maritima, exhibits sizeable variation in the extent of directional asymmetry within and across body sizes, making it an ideal candidate for investigating the function of asymmetry. In this study, we characterized the extent of weapon asymmetry, characterized the manner in which asymmetric weapons are used in contests, staged dyadic contests between males of different size classes and analyzed the correlates of fighting success. In contests between large males, larger individuals won more fights and emerged as the dominant male. In contests between small males, however, weapon asymmetry was more influential in predicting overall fighting success than body size. This result reveals an advantage of asymmetric weaponry among males that are below the mean size in the population. A forceps manipulation experiment suggests that asymmetry may be an indirect, correlate of a morphologically independent factor that affects fighting ability. PMID:22984320

A general description of additive and nonadditive elements of sperm competitiveness and their relation to male fertilization success.

Science.gov (United States)

Engqvist, Leif

2013-05-01

A complete understanding of male reproductive success, and thus sexual selection, often requires an insight into male success in sperm competition. Genuine conclusions on male sperm competitiveness can only be made in real competitive situations. However, statistical analyses of sperm competitiveness from fertilization success data have been shown to be problematic. Here, I first outline a comprehensive general description of the different additive and nonadditive elements relevant for the outcome of sperm competition staged between two males. Based on this description, I will highlight two main problems that are frequently encountered in experiments aiming at estimating sperm competitiveness. First, I focus on potential problems when using standardized competitors versus random mating trials, because trials with standardized competitors do not allow generalization if male-male interactions are important. Second, I illustrate the necessity to analyze data on the logit scale rather than on raw proportions, because only the logit scale allows a clean separation of additive and nonadditive effects (i.e., male × male and female × male interactions). © 2012 The Author(s). Evolution © 2012 The Society for the Study of Evolution.

Premarital sexual behavior among male college students of Kathmandu, Nepal.

Science.gov (United States)

Adhikari, Ramesh; Tamang, Jyotsna

2009-07-15

In Nepal, as in other Asian countries, the issue of sexuality still remains a taboo. Despite this fact, an increasing number of sexual activities is being reported by Nepalese students. This trend warrants serious and timely attention. Due to the sensitivity of the topic of premarital sexuality, youth receive inadequate education, guidance and services on reproductive health. The main objectives of this paper are to explore the sexual behavior especially focusing on prevalence of premarital sex among college men and to investigate the factors surrounding premarital sexual behavior. A cross-sectional survey of college students was conducted in April-May 2006. A self-administered questionnaire was completed by 573 male students. Association between premarital sex and the explanatory variables was assessed in bivariate analysis using Chi-square tests. The associations were further explored using multivariate logistic analysis. Despite the religious and cultural restrictions, about two-fifths of survey respondents (39%) reported that they have had premarital sex. The study has also shown that substantial proportions of students indulge in sexual activities as well as risky sexual behavior. Sex with commercial sex workers, multiple sex partners, and inconsistence use of condom with non-regular partner was common among the students. Less than two in five male students (57%) had used condom at the first sexual intercourse.The prevalence of premarital sex varied on different settings. Older students aged 20 and above were more likely to have premarital sex compared with younger students aged 15-19. Men who had liberal attitude towards male virginity at marriage were almost two times more likely to have engaged in premarital sex compared to their counterparts who have conservative attitude towards male virginity at marriage. Moreover, those students who believe in Hindu religion were more than two times (OR = 2.5) more likely to have premarital sex compared with those who

Evolution of male and female genitalia following release from sexual selection.

Science.gov (United States)

Cayetano, Luis; Maklakov, Alexei A; Brooks, Robert C; Bonduriansky, Russell

2011-08-01

Despite the key functions of the genitalia in sexual interactions and fertilization, the role of sexual selection and conflict in shaping genital traits remains poorly understood. Seed beetle (Callosobruchus maculatus) males possess spines on the intromittent organ, and females possess a thickened reproductive tract wall that also bears spines. We investigated the role of sexual selection and conflict by imposing monogamous mating on eight replicate populations of this naturally polygamous insect, while maintaining eight other populations under polygamy. To establish whether responses to mating system manipulation were robust to ecological context, we simultaneously manipulated life-history selection (early/late reproduction). Over 18-21 generations, male genital spines evolved relatively reduced length in large males (i.e., shallower static allometry) in monogamous populations. Two nonintromittent male genital appendages also evolved in response to the interaction of mating system and ecology. In contrast, no detectable evolution occurred in female genitalia, consistent with the expectation of a delayed response in defensive traits. Our results support a sexually antagonistic role for the male genital spines, and demonstrate the evolution of static allometry in response to variation in sexual selection opportunity. We argue that further advances in the study of genital coevolution will require a much more detailed understanding of the functions of male and female genital traits. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

Treatment of Male Sexual Offenders in a Correctional Facility.

Science.gov (United States)

Whitford, Robert W.

1987-01-01

Provides some background and treatment perspectives for counselors and psychologists who treat or contemplate treatment of adult male sexual offenders in prison settings. Discusses identification, assessment, amenability to treatment, assessment instruments, and treatment of sexual offenders. (ABL)

The organizational effects of pubertal testosterone on sexual proficiency in adult male Syrian hamsters.

Science.gov (United States)

De Lorme, Kayla C; Sisk, Cheryl L

2016-10-15

Social proficiency requires making appropriate behavioral adaptations as a result of social experience. For example, male rodents become sexually proficient with experience as demonstrated by a reduction in ectopic (misdirected) mounts, mount-to-intromission ratio, and latency to ejaculation. We previously found that over a series of timed tests with a receptive female, male hamsters deprived of testosterone specifically during puberty (NoT@P) have overall lower levels of sexual behavior and continue to display high levels of ectopic mounts, compared with males that experienced endogenous testosterone during puberty (T@P). These results suggested that pubertal testosterone programs sexual proficiency in adulthood, but because NoT@P males engaged in less sexual behavior than T@P males in these tests, the amount of sexual experience may have been insufficient to improve sexual proficiency. To more rigorously test the hypothesis that pubertal testosterone is necessary for social proficiency in adulthood, the present study compared the behavior of NoT@P and T@P males in a series of 4 trials with a 48-h interval between each trial. Sexual experience was equated by limiting each trial to 5 intromissions. Sexually-naïve males were either gonadectomized prepubertally (NoT@P) or in adulthood (T@P) and received subcutaneous testosterone capsules four weeks later. Two weeks after testosterone replacement, these groups and a group of adult gonad-intact controls began sexual behavior testing. We found that NoT@P males had more ectopic mounts/min across all four tests compared to gonad-intact and T@P males. Moreover, both gonad-intact and T@P males, but not NoT@P males, showed an increase in the number of mounts and intromissions/min between trials 1 and 3. Unexpectedly, both gonad-intact and T@P, but not NoT@P, males showed a decrease in sexual behaviors during trial 4. Thus, T@P males display multiple behavioral adaptations to sexual experience that are not observed in No

Sexually Abused Male Adolescents: How Vulnerable Are They?

Science.gov (United States)

Chandy, Joseph M.; Blum, Robert Wm.; Resnick, Michael D.

1997-01-01

Examined the suicidal involvement, disordered eating behaviors, sexual risk taking, delinquent behaviors, substance use, and school performance of male teenagers (N=370) with a reported history of sexual abuse. Results show that, except for school performance, this group had higher rates of adverse correlates in the above areas than did a control…

Development of muscularity and weight concerns in heterosexual and sexual minority males.

Science.gov (United States)

Calzo, Jerel P; Corliss, Heather L; Blood, Emily A; Field, Alison E; Austin, S Bryn

2013-01-01

To examine the development of muscularity and weight concerns among heterosexual and sexual minority males in adolescence. Participants were 5,868 males from the Growing Up Today Study, a U.S. prospective cohort spanning ages 9-25 years. Generalized estimating equations were used to test sexual orientation differences in the development of muscularity concerns, weight gain attempts, and weight and shape concern. Desire for bigger muscles increased slightly each year across adolescence (β = .10, 95% C.I. = .09, .11) regardless of sexual orientation, but gay and bisexual participants reported greater desire for toned muscles than completely and mostly heterosexual males (β = .39, 95% C.I. = .21, .57). Desire for toned muscles did not change with age. Attempts to gain weight increased threefold across adolescence, with up to 30% reporting weight gain attempts by age 16. Although underweight males (the smallest weight status class) were most likely to attempt to gain weight, most of the observed weight gain attempts were by healthy (69%) and overweight/obese (27%) males, suggesting that most attempts were medically unnecessary and could lead to overweight. Sexual minority participants were 20% less likely to report weight gain attempts than completely heterosexual participants. Weight and shape concern increased with age, with gay and bisexual participants experiencing a significantly greater increase than heterosexual males. Sexual orientation modifies the development and expression of male weight and muscularity concerns. The findings have implications for early interventions for the prevention of obesity and eating disorder risk in heterosexual and sexual minority males. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Acute and chronic dosing of Lepidium meyenii (Maca) on male rat sexual behavior.

Science.gov (United States)

Lentz, Aaron; Gravitt, Karla; Carson, Culley C; Marson, Lesley

2007-03-01

The use of natural remedies for the treatment of sexual disorders is under current investigation. For generations people of the rural community in Peru have used Lepidium meyenii Walpers (Maca), because of their belief that it improves fertility and sexual desire. To determine the acute and chronic effects of Maca on male sexual behavior and to examine chronic administration of Maca on anxiety. Ejaculatory and mounting behavior and postejaculatory interval. Anxiety tests using an elevated plus maze, locomotion, and social interaction with another male. Maca (25 and 100 mg/kg) was orally administered to male rats for 30 days. Male sexual behavior was monitored after acute, 7 and 21 days of treatment. Anxiety behavior and locomotion were measured at 28-29 days using the elevated plus maze and social interaction tests. Maca treatment did not produce large changes in male sexual behavior. However, an increase in ejaculation latency and postejaculatory interval was observed after both acute and 7 days of treatment. After 21 days of treatment Maca had no effect on sexual behavior. Chronic administration of Maca did not increase locomotion or anxiety. Acute and short-term administration of Maca produced a small effect of rat male sexual behavior and long-term administration did not increase anxiety.

Sexual function of the ageing male.

Science.gov (United States)

Corona, Giovanni; Rastrelli, Giulia; Maseroli, Elisa; Forti, Gianni; Maggi, Mario

2013-08-01

With the progressive increase in the proportion of older people, there is an increasing interest in characterizing the modifications of sexual health and the effect of its perturbations as a function of the aging process. The aim of this review is to summarize the available evidence regarding the age-dependent modifications of male sexual function and their interaction with general health and age-dependent modification of endocrine function. Elderly patients are often affected by multiple organic diseases which can interfere with sexual function. Despite this evidence, several studies have indicated that, with advancing age, normal erections are not an absolute prerequisite to remain sexually active. Good physical health, the availability of a partner, and a regular and stable pattern of sexual activity earlier in life predict the maintenance of sexual activity in old age. Conversely, there are no convincing data that hormonal changes, associated with aging, have a primary role in underlying changes in sexual function in healthy aging men. Nonetheless, sexual dysfunctions especially in elderly people are poor investigated. Asking about sexual health remains difficult or embarrassing for many primary care physicians. In addition, many patients find it difficult to raise sexual issues with their doctor. This situation often results in sexual issues not being adequately addressed thus resulting in depression, social withdrawal and delayed diagnosis of underlying medical conditions often resulting in forthcoming cardiovascular events. Education and permission from a health care professional may help to alter such misconceptions. Information from physicians regarding normal age-related changes in sexuality and encouragement, together with advice on how to continue meaningful sexual relations, may play a key role in altering such negative attitudes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Attraction and consumption of methyl eugenol by male Bactrocera umbrosa Fabricius (Diptera: Tephritidae) promotes conspecific sexual communication and mating performance.

Science.gov (United States)

Wee, S L; Abdul Munir, M Z; Hee, A K W

2018-02-01

The Artocarpus fruit fly, Bactrocera umbrosa (Fabricius) (Diptera: Tephritidae), is an oligophagous fruit pest infesting Moraceae fruits, including jackfruit (Artocarpus heterophyllus Lamarck), a fruit commodity of high value in Malaysia. The scarcity of fundamental biological, physiological and ecological information on this pest, particularly in relation to behavioural response to phytochemical lures, which are instrumental to the success of many area-wide fruit fly control and management programmes, underpins the need for studies on this much-underrated pest. The positive response of B. umbrosa males to methyl eugenol (ME), a highly potent phytochemical lure, which attracts mainly males of many Bactrocera species, was shown to increase with increasing age. As early as 7 days after emergence (DAE), ca. 22% of males had responded to ME and over 50% by 10 DAE, despite no occurrence of matings (i.e. the males were still sexually immature). Male attraction to ME peaked from 10 to 27 DAE, which corresponded with the flies' attainment of sexual maturity. In wind-tunnel assays during the dusk courtship period, ME-fed males exhibited earlier calling activity and attracted a significantly higher percentage of virgin females compared with ME-deprived males. ME-fed males enjoyed a higher mating success than ME-deprived males at 1-day post ME feeding in semi-field assays. ME consumption also promotes aggregation behaviour in B. umbrosa males, as demonstrated in wind-tunnel and semi-field assays. We suggest that ME plays a prominent role in promoting sexual communication and enhancing mating performance of the Artocarpus fruit fly, a finding that is congruent with previous reports on the consequences of ME acquisition by other economically important Bactrocera species.

Nuclear medicine procedures for the evaluation of male sexual organs: a brief review

Energy Technology Data Exchange (ETDEWEB)

Bernardo-Filho, Mario; Santos-Filho, Sebastiao David; Fonseca, Adenilson de Souza da [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Biologia Roberto Alcantara Gomes. Lab. de Radiofarmacia Experimental; Carter, Kevin [Harvard Univ., Boston, MA (United States). Brigham and Women' s Hospital. Dept. of Radiology; Missailidis, Sotiris [The Open University, Milton Keynes (United Kingdom). Dept. of Chemistry and Analytical Sciences

2008-12-15

Sexuality consists of three aspects that are interrelated and inseparable, biological, physiological and social. The biological aspect considers the individual's capability to give and to receive pleasure. In consequence, it covers the functionality of the sexual organs and the physiology of human sexual response cycle. Diagnostic imaging modalities, such as single photon emission computed tomography (SPECT) and positron emission tomography (PET) have been used to evaluate clinical disorders of the male reproductive system. PET and SPECT procedures basically involve the administration of a radiopharmaceutical that has a higher uptake in a specific tumor or tissue. The aim of this brief review is to present some radiopharmaceuticals that have been used in the clinical evaluation of the male sexual organs (testes, prostate, seminal vesicles, penis) related with male sexuality. This information could be useful in better understanding the male sexual response cycle, as well as the sexual disorders, when considering the male sexual organs and the pelvic floor. Moreover, the findings obtained with PET and SPECT imaging could help to evaluate the efficacy of clinical results of therapeutic procedures. In conclusion, the knowledge from these images could aid in better understanding the physiology of the different organs related with sexuality. Furthermore, they could be important tools to evaluate the physiological integrity of the involved organs, to improve clinical strategies and to accompany the patients under treatment. (author)

Nuclear medicine procedures for the evaluation of male sexual organs: a brief review

International Nuclear Information System (INIS)

Bernardo-Filho, Mario; Santos-Filho, Sebastiao David; Fonseca, Adenilson de Souza da; Carter, Kevin; Missailidis, Sotiris

2008-01-01

Sexuality consists of three aspects that are interrelated and inseparable, biological, physiological and social. The biological aspect considers the individual's capability to give and to receive pleasure. In consequence, it covers the functionality of the sexual organs and the physiology of human sexual response cycle. Diagnostic imaging modalities, such as single photon emission computed tomography (SPECT) and positron emission tomography (PET) have been used to evaluate clinical disorders of the male reproductive system. PET and SPECT procedures basically involve the administration of a radiopharmaceutical that has a higher uptake in a specific tumor or tissue. The aim of this brief review is to present some radiopharmaceuticals that have been used in the clinical evaluation of the male sexual organs (testes, prostate, seminal vesicles, penis) related with male sexuality. This information could be useful in better understanding the male sexual response cycle, as well as the sexual disorders, when considering the male sexual organs and the pelvic floor. Moreover, the findings obtained with PET and SPECT imaging could help to evaluate the efficacy of clinical results of therapeutic procedures. In conclusion, the knowledge from these images could aid in better understanding the physiology of the different organs related with sexuality. Furthermore, they could be important tools to evaluate the physiological integrity of the involved organs, to improve clinical strategies and to accompany the patients under treatment. (author)

Differential courtship activity and alterations of reproductive success of competing gupply males as an indicator for low concentrations of aquatic pollutants

Energy Technology Data Exchange (ETDEWEB)

Schroeder, J.H.; Peters, K.

1988-09-01

Differential courtship activity of guppy males competing for the same females was used as a bioindicator for low concentrations of water-borne pollutants in a previous study. Patterns of male sexual activity were chosen because they determine reproductive success. The mean difference between courtship activities of two male competitors determines the relative fitness of the male in question. Accordingly, the decrease in mean differential courtship after exposure to aquatic contaminants was predicted to cause a corresponding change in the relative reproductive success. The present study completed the previous one by repeating the experiment with a 10% addition of wastewater drawn from the last clearing basin of a Munich purification plant this time using virgin (non-inseminated) females which were receptive to male courtship. The females subsequently were allowed to produce as many offspring as possible. The number of young guppies sired by individual male competitors could easily be traced by the use of sex-linked phenotypic color patterns as markers. The purpose of these two studies was to show that the quantification of sexual activities of male guppies is useful for monitoring environmental alterations which affect fitness characters.

Men with sexual interest in transvestites, transsexuals, and she-males.

Science.gov (United States)

Blanchard, R; Collins, P I

1993-09-01

This study was a preliminary exploration of gynandromorphophilia, that is, sexual interest in cross-dressed or anatomically feminized men. Subjects were male subscribers to a voice mail system devoted to personal advertisements for sexual or romantic partners. These comprised 51 gynandromorphophiles who sought cross-dressers, transvestites, transsexuals, or she-males for such relationships, 37 gynandromorphophilic cross-dressers who identified themselves as cross-dressers and sought similar men, and 31 residual cross-dressers who sought masculine or unspecified male partners. Analysis of advertisement content suggested that gynandromorphophilia constitutes a distinct erotic interest.

Prenatal undernutrition disrupted the sexual maturation, but not the sexual behavior, in male rats.

Science.gov (United States)

Matsuzaki, Toshiya; Munkhzaya, Munkhsaikhan; Tungalagsuvd, Altankhuu; Mayila, Yiliyasi; Iwasa, Takeshi; Yano, Kiyohito; Yanagihara, Rie; Tokui, Takako; Kato, Takeshi; Kuwahara, Akira; Matsui, Sumika; Irahara, Minoru

2017-10-01

Exposure to various stressors, including psychological, metabolic, and immune, in the perinatal period induces long-lasting effects in physiological function and increase the risk of metabolic disorders in later life. In the present study, sexual maturation and sexual behavior were assessed in prenatally undernourished mature male rats. All the pregnant rats were divided into the maternal normal nutrition (mNN) group and the maternal undernutrition (mUN) group. The mUN mothers received 50% of the amount of the daily food intake of the mNN mothers. Preputial separation and sexual behavior were observed in randomly selected pups of the mNN and mUN groups. The body weight of the mothers was significantly lighter in the mUN group than in the mNN group. Similarly, the pups in the mUN group showed a significantly lower body weight than those in the mNN group from postnatal day (PND) 1 to PND 15. The preputial separation day was significantly delayed in the mUN group, compared to the mNN group. Sexual behavior did not show any significant difference between the two groups. These findings indicated that prenatal undernutrition delayed sexual maturation, but did not suppress sexual behavior, in mature male rats.

Characteristics of Female Solo and Female Co-Offenders and Male Solo Sexual Offenders Against Children.

Science.gov (United States)

Williams, Rebecca; Gillespie, Steven M; Elliott, Ian A; Eldridge, Hilary J

2017-09-01

Studies have highlighted differences in the victim choice, offender, and offense characteristics of female and male sexual offenders. However, little is known about how solo and co-offending females differ from solo male sexual offenders. We compared the characteristics of 20 solo and 20 co-offending females (co-offended with a male and/or female accomplice), and 40 male sexual offenders against children. We found that solo female offenders showed the most evidence of personal problems, including depression and sexual dissatisfaction. Compared with male offenders, female co-offenders showed poorer self-management, but better sexual self-regulation. Male offenders had a greater history of offending and showed more evidence of sexual abuse supportive cognitions relative to both solo and co-offending females. These results are consistent with the need for a gender-specific approach to working with sexual offenders and may have implications for understanding the often complex treatment needs of these clients.

Male-limited evolution suggests no extant intralocus sexual conflict ...

Indian Academy of Sciences (India)

Male-limited evolution suggests no extant intralocus sexual conflict over the sexually dimorphic cuticular hydrocarbons of Drosophila melanogaster ... Spain; Indian Institute of Science Education and Research, Mohali, Knowledge City, Sector 81, SAS Nagar, Manauli PO 140 306, India; Department of Biology and Centre for ...

Socio-Economic Perspectives of Male Sexual Challenges and Inter ...

African Journals Online (AJOL)

Socio-Economic Perspectives of Male Sexual Challenges and Inter-Spousal Communication in a Mono-Cultural Setting. ... for all men who have sexual health challenges in order to stimulate mutual harmonious communication between husband and wife and enhance effective management of crisis at home fronts.

Sexually selected nest-building--Pomatoschistus minutus males build smaller nest-openings in the presence of sneaker males.

Science.gov (United States)

Svensson, O; Kvarnemo, C

2003-09-01

Both natural selection and sexual selection may act on nest-building. We tested experimentally how different regimes of egg-predation and male-male competition influence nest-building before mating, using the marine fish sand goby, Pomatoschistus minutus. Males with sneaker males present built the smallest nest-openings, smaller than males held alone or with Pomatoschistus microps males (which may predate eggs and compete over nest-sites but not compete over fertilizations). Males with visual access to other nest-building males tended also to build smaller openings than males held alone or with P. microps. Males with egg-predators present built nests with openings not differing significantly from any other treatment. Our results indicate that the small nest-openings found in the sneaker male treatment are sexually selected through protection against sneaking or by female choice. Across treatments, time span before a male started to build his nest also explained variation in nest-opening width; males starting late built larger nest-openings.

Sexual function in male patients with obstructive sleep apnoea

DEFF Research Database (Denmark)

Petersen, Marian; Kristensen, Ellids; Berg, Søren

2010-01-01

OBJECTIVE: Our objective was to investigate general and functional aspects of sexuality in male patients with a confirmed diagnosis of obstructive sleep apnoea (OSA) and compare the results with normative data. MATERIALS AND METHODS: We investigated 308 male patients (age 30-69) admitted to a sleep...... of sexuality were worse in patients with (untreated) OSA when compared with normative data. Both aspects were dependent on age, obesity, social factors and concomitant medication but not on the severity of OSA as reflected by the apnoea-hypopnoea index or subjective sleepiness. CONCLUSION: We conclude...... that although sexual dysfunction is more prevalent in OSA patients than in the general population, it is a complex problem relating more to age, obesity, social factors and comorbidity than to the severity of OSA....

Nucleus Accumbens Dopamine Signaling Regulates Sexual Preference for Females in Male Mice.

Science.gov (United States)

Beny-Shefer, Yamit; Zilkha, Noga; Lavi-Avnon, Yael; Bezalel, Nadav; Rogachev, Ilana; Brandis, Alexander; Dayan, Molly; Kimchi, Tali

2017-12-12

Sexual preference for the opposite sex is a fundamental behavior underlying reproductive success, but the neural mechanisms remain unclear. Here, we examined the role of dopamine signaling in the nucleus accumbens core (NAcc) in governing chemosensory-mediated preference for females in TrpC2 -/- and wild-type male mice. TrpC2 -/- males, deficient in VNO-mediated signaling, do not display mating or olfactory preference toward females. We found that, during social interaction with females, TrpC2 -/- males do not show increased NAcc dopamine levels, observed in wild-type males. Optogenetic stimulation of VTA-NAcc dopaminergic neurons in TrpC2 -/- males during exposure to a female promoted preference response to female pheromones and elevated copulatory behavior toward females. Additionally, we found that signaling through the D1 receptor in the NAcc is necessary for the olfactory preference for female-soiled bedding. Our study establishes a critical role for the mesolimbic dopaminergic system in governing pheromone-mediated responses and mate choice in male mice. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Nucleus Accumbens Dopamine Signaling Regulates Sexual Preference for Females in Male Mice

Directory of Open Access Journals (Sweden)

Yamit Beny-Shefer

2017-12-01

Full Text Available Sexual preference for the opposite sex is a fundamental behavior underlying reproductive success, but the neural mechanisms remain unclear. Here, we examined the role of dopamine signaling in the nucleus accumbens core (NAcc in governing chemosensory-mediated preference for females in TrpC2−/− and wild-type male mice. TrpC2−/− males, deficient in VNO-mediated signaling, do not display mating or olfactory preference toward females. We found that, during social interaction with females, TrpC2−/− males do not show increased NAcc dopamine levels, observed in wild-type males. Optogenetic stimulation of VTA-NAcc dopaminergic neurons in TrpC2−/− males during exposure to a female promoted preference response to female pheromones and elevated copulatory behavior toward females. Additionally, we found that signaling through the D1 receptor in the NAcc is necessary for the olfactory preference for female-soiled bedding. Our study establishes a critical role for the mesolimbic dopaminergic system in governing pheromone-mediated responses and mate choice in male mice.

PPL2ab neurons restore sexual responses in aged Drosophila males through dopamine.

Science.gov (United States)

Kuo, Shu-Yun; Wu, Chia-Lin; Hsieh, Min-Yen; Lin, Chen-Ta; Wen, Rong-Kun; Chen, Lien-Cheng; Chen, Yu-Hui; Yu, Yhu-Wei; Wang, Horng-Dar; Su, Yi-Ju; Lin, Chun-Ju; Yang, Cian-Yi; Guan, Hsien-Yu; Wang, Pei-Yu; Lan, Tsuo-Hung; Fu, Tsai-Feng

2015-06-30

Male sexual desire typically declines with ageing. However, our understanding of the neurobiological basis for this phenomenon is limited by our knowledge of the brain circuitry and neuronal pathways controlling male sexual desire. A number of studies across species suggest that dopamine (DA) affects sexual desire. Here we use genetic tools and behavioural assays to identify a novel subset of DA neurons that regulate age-associated male courtship activity in Drosophila. We find that increasing DA levels in a subset of cells in the PPL2ab neuronal cluster is necessary and sufficient for increased sustained courtship in both young and aged male flies. Our results indicate that preventing the age-related decline in DA levels in PPL2ab neurons alleviates diminished courtship behaviours in male Drosophila. These results may provide the foundation for deciphering the circuitry involved in sexual motivation in the male Drosophila brain.

Relationship Between Use of Videogames and Sexual Health in Adult Males.

Science.gov (United States)

Sansone, Andrea; Sansone, Massimiliano; Proietti, Marco; Ciocca, Giacomo; Lenzi, Andrea; Jannini, Emmanuele A; Romanelli, Francesco

2017-07-01

Videogame use is increasingly prevalent in people of all ages, and despite the wide amount of scientific evidence proving a role for electronic entertainment in human health, there is no evidence about the relation between use of videogames and sexual health. To investigate the association between use of videogames and male sexual health. We administered the two validated questionnaires, the Premature Ejaculation Diagnostic Tool (PEDT) and the International Index of Erectile Function (IIEF-15), to men 18 to 50 years old recruited through social networks and specific websites. In addition to the questionnaires, volunteers were asked to provide information on their gaming habit and lifestyle. An extended version of the IIEF-15 and PEDT, including data about gaming habits and relevant lifestyles. From June 18, 2014 through July 31, 2014, 599 men 18 to 50 years old completed the questionnaires. One hundred ninety-nine men reported no sexual activity during the previous 4 weeks; four records were rejected because of inherent errors. The remaining 396 questionnaires were analyzed, with 287 "gamers" (playing >1 hour/day on average) and 109 "non-gamers" providing all the required information. We found a lower prevalence of premature ejaculation in gamers compared with non-gamers (mean PEDT score = 3.57 ± 3.38 vs 4.52 ± 3.7, P videogame use and male sexual health. Compared with non-gamers, men playing videogames for more than 1 hour/day were less likely to have premature ejaculation but more likely to have decreased sexual desire. This is the first study aimed to assess male sexual health in gamers. We identified an association between PEDT and IIEF scores and videogame use; however, these findings require validation through interventional studies. Furthermore, volunteers were recruited through social networks, thus increasing the risk of recruitment bias. To our knowledge, this is the first observational study investigating the link between electronic entertainment and

Programming effects of antenatal corticosteroids exposure in male sexual behavior.

Science.gov (United States)

Oliveira, Mário; Leão, Pedro; Rodrigues, Ana-João; Pêgo, José-Miguel; Cerqueira, João-José; Sousa, Nuno

2011-07-01

Brain regions implicated in sexual behavior begin to differentiate in the last trimester of gestation. Antenatal therapy with corticosteroids is often used in clinical practice during this period to accelerate lung maturation in preterm-risk pregnancies. Clinical and animal studies highlighted major behavioral impairments induced later in life by these treatments, especially when synthetic corticosteroids are used. To evaluate the implications of acute prenatal treatment with natural vs. synthetic corticosteroids on adult male rat sexual behavior and its neurochemical correlates. Twelve pregnant Wistar rats were injected with dexamethasone (DEX-1 mg/kg), corticosterone (CORT-25 mg/kg), or saline on late gestation (pregnancy days 18 and 19). Following this brief exposure to corticosteroids, we assessed the sexual behavior of the adult male progeny and subsequently associated these behaviors with the levels of catecholamines and mRNA of dopamine and androgen receptors (AR) in brain regions relevant for sexual behavior. Sexual behavior of adult male offspring was assessed by exposure to receptive females. This was associated with serum testosterone levels and levels of catecholamines (determined by high-performance liquid chromatography) and dopamine and AR mRNA expression (real-time polymerase chain reaction [PCR]) in brain regions implicated in sexual behavior. Prenatal DEX exposure resulted in a decreased number and increased mounts and intromissions latencies in adulthood. These findings were associated with decreased levels of serum testosterone and increased hypothalamic expression of AR mRNA. DEX animals also displayed lower dopamine levels and higher dopamine receptor mRNA expression both in hypothalamus and nucleus accumbens (NAcc). The milder phenotype of CORT animals was associated only with decreased dopamine levels in NAcc. Antenatal corticotherapy programs adult male sexual behavior through changes in specific neuronal and endocrine mediators

Characteristics and allowed behaviors of gay male couples' sexual agreements.

Science.gov (United States)

Mitchell, Jason W

2014-01-01

Research has shown that gay male couples' sexual agreements may affect their risk for HIV. Few U.S. studies have collected dyadic data nationally from gay male couples to assess what sexual behaviors they allow to occur by agreement type and the sequence of when certain behaviors occur within their relationships. In our cross-sectional study, dyadic data from a convenience sample of 361 male couples were collected electronically throughout the United States by using paid Facebook ads. Findings revealed that couples discussed their HIV status before having unprotected anal intercourse (UAI) but established their agreement some time after having UAI. About half of the couples (N = 207) concurred about having an agreement. Among these couples, 58% concurred about explicitly discussing their agreement, 84% concurred about having the same type of agreement, and 54% had both men adhering to it. A variety of sexual behaviors were endorsed and varied by agreement type. Concordance about aspects of couples' agreements varied, suggesting the need to engage couples to be more explicit and detailed when establishing and communicating about their agreements. The allowed behaviors and primary reasons for establishing and breaking sexual agreements further highlight the need to bolster HIV prevention for gay male couples.

Sexual size dimorphism, canine dimorphism, and male-male competition in primates: where do humans fit in?

Science.gov (United States)

Plavcan, J Michael

2012-03-01

Sexual size dimorphism is generally associated with sexual selection via agonistic male competition in nonhuman primates. These primate models play an important role in understanding the origins and evolution of human behavior. Human size dimorphism is often hypothesized to be associated with high rates of male violence and polygyny. This raises the question of whether human dimorphism and patterns of male violence are inherited from a common ancestor with chimpanzees or are uniquely derived. Here I review patterns of, and causal models for, dimorphism in humans and other primates. While dimorphism in primates is associated with agonistic male mate competition, a variety of factors can affect male and female size, and thereby dimorphism. The causes of human sexual size dimorphism are uncertain, and could involve several non-mutually-exclusive mechanisms, such as mate competition, resource competition, intergroup violence, and female choice. A phylogenetic reconstruction of the evolution of dimorphism, including fossil hominins, indicates that the modern human condition is derived. This suggests that at least some behavioral similarities with Pan associated with dimorphism may have arisen independently, and not directly from a common ancestor.

Male victims of sexual assault; 10 years' experience from a Danish Assault Center

DEFF Research Database (Denmark)

Larsen, Mie-Louise; Hilden, Malene

2016-01-01

This study aims to provide descriptive data regarding male victims of sexual assault seen at the Centre for Victims of Sexual Assault in Copenhagen, Denmark. All 55 male victims attending the center in the time period of March 2001 until December 2010 underwent a standardized data collection. Data...... by another man is considered a taboo subject and it is likely that the dark figure of men exposed to sexual assault is much higher than it is for women. Strengthening our knowledge regarding male victims of sexual assault is necessary to improve both primary and secondary preventive measures in order to make...

Effects of zinc supplementation on sexual behavior of male rats

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DMAB Dissanayake

2009-01-01

Full Text Available Context: Effects of zinc on male sexual competence are poorly understood. Aim: To study the effects of different doses of zinc on the sexual competence of males using a rat model. Materials and Methods: Three subsets (eight in each subset of sexually experienced adult male rats were supplemented with three different oral doses of zinc sulphate (a daily dose of 1 mg, 5 mg and 10 mg respectively for two weeks. A subset of eight animals without zinc supplementation was used as the control group Sexual behavior was observed by placing them individually in cages with receptive females. Statistical Analysis : Data analysis was done using SPSS v10 for windows computer software. Results: Supplementation of 5 mg of zinc/day for two weeks led to a prolongation of ejaculatory latency; 711.6 sec. (SEM 85.47 vs. 489.50 sec. (SEM 67.66, P 0.05. However, partner preference index was positive and 5 mg zinc supplementation did not exert a significant adverse effect on the muscle strength and co-ordination. The subset of rats supplemented with 1 mg/day did not show a difference from the control group while supplementation with 10 mg/day led to a reduction of the libido index, number of mounts and intromissions. Conclusions : Zinc therapy improves sexual competence of male rats; the effect is dose dependent. Increase in the T levels is beneficial in this regard. However, increase in PRL is responsible for the reduced libido index. Further studies on pigs and monkeys are needed to evaluate the therapeutic use of zinc in sexual dysfunction.

Sexual Function in Males After Radiotherapy for Rectal Cancer

International Nuclear Information System (INIS)

Bruheim, Kjersti; Guren, Marianne G.; Dahl, Alv A.; Skovlund, Eva; Balteskard, Lise; Carlsen, Erik; Fossa, Sophie D.; Tveit, Kjell Magne

2010-01-01

Purpose: Knowledge of sexual problems after pre- or postoperative radiotherapy (RT) with 50 Gy for rectal cancer is limited. In this study, we aimed to compare self-rated sexual functioning in irradiated (RT+) and nonirradiated (RT-) male patients at least 2 years after surgery for rectal cancer. Methods and Materials: Patients diagnosed with rectal cancer from 1993 to 2003 were identified from the Norwegian Rectal Cancer Registry. Male patients without recurrence at the time of the study. The International Index of Erectile Function, a self-rated instrument, was used to assess sexual functioning, and serum levels of serum testosterone were measured. Results: Questionnaires were returned from 241 patients a median of 4.5 years after surgery. The median age was 67 years at survey. RT+ patients (n = 108) had significantly poorer scores for erectile function, orgasmic function, intercourse satisfaction, and overall satisfaction with sex life compared with RT- patients (n = 133). In multiple age-adjusted analysis, the odds ratio for moderate-severe erectile dysfunction in RT+ patients was 7.3 compared with RT- patients (p <0.001). Furthermore, erectile dysfunction of this degree was associated with low serum testosterone (p = 0.01). Conclusion: RT for rectal cancer is associated with significant long-term effects on sexual function in males.

Sexual selection on receptor organ traits: younger females attract males with longer antennae

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Johnson, Tamara L.; Symonds, Matthew R. E.; Elgar, Mark A.

2017-06-01

Sexual selection theory predicts that female choice may favour the evolution of elaborate male signals. Darwin also suggested that sexual selection can favour elaborate receiver structures in order to better detect sexual signals, an idea that has been largely ignored. We evaluated this unorthodox perspective by documenting the antennal lengths of male Uraba lugens Walker (Lepidoptera: Nolidae) moths that were attracted to experimentally manipulated emissions of female sex pheromone. Either one or two females were placed in field traps for the duration of their adult lives in order to create differences in the quantity of pheromone emissions from the traps. The mean antennal length of males attracted to field traps baited with a single female was longer than that of males attracted to traps baited with two females, a pattern consistent with Darwin's prediction assuming the latter emits higher pheromone concentrations. Furthermore, younger females attracted males with longer antennae, which may reflect age-specific changes in pheromone emission. These field experiments provide the first direct evidence of an unappreciated role for sexual selection in the evolution of sexual dimorphism in moth antennae and raise the intriguing possibility that females select males with longer antennae through strategic emission of pheromones.

Cocaine induces state-dependent learning of sexual conditioning in male Japanese quail.

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Gill, Karin E; Rice, Beth Ann; Akins, Chana K

2015-01-01

State dependent learning effects have been widely studied in a variety of drugs of abuse. However, they have yet to be studied in relation to sexual motivation. The current study investigated state-dependent learning effects of cocaine in male Japanese quail (Coturnix japonica) using a sexual conditioning paradigm. Cocaine-induced state-dependent learning effects were investigated using a 2×2 factorial design with training state as one factor and test state as the other factor. During a 14-day training phase, male quail were injected once daily with 10mg/kg cocaine or saline and then placed in a test chamber after 15min. In the test chamber, sexual conditioning trials consisted of presentation of a light conditioned stimulus (CS) followed by sexual reinforcement. During the state dependent test, half of the birds received a shift in drug state from training to testing (Coc→Sal or Sal→Coc) while the other half remained in the same drug state (Coc→Coc or Sal→Sal). Results showed that male quail that were trained and tested in the same state (Coc→Coc or Sal→Sal) showed greater sexual conditioning than male quail that were trained and tested in different states (Sal→Coc) except when cocaine was administered chronically prior to the test (Coc→Sal). For the latter condition, sexual conditioning persisted from cocaine training to the saline test. The findings suggest that state dependent effects may alter sexual motivation and that repeated exposure to cocaine during sexual activity may increase sexual motivation which, in turn, may lead to high risk sexual activities. An alternative explanation for the findings is also discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

[Influence of aging on male sexual health].

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Seisen, T; Rouprêt, M; Costa, P; Giuliano, F

2012-06-01

With the increase in life expectancy, men's sexual health has become a major concern for elderly couples. Erectile dysfunction (ED) is responsible for a 50 % decrease of sexually active men between 60 and 85. The aim of this study was to identify objective elements to evaluate the influence of age on male sexual health. Data on the effects of aging on men's sexual health have been explored in Medline and Embase using the MeSH keywords: prostate; sexuality and erectile dysfunction; aging. The articles were selected based on their methodology, relevance, date and language of publication. ED concerns 64 % of 70 years old patients and up to 77.5 % after 75 years. The screening of this pathology is based on standardized diagnostic tools. The most used of them remains the "International Index of Erectile function" which, in its simplified version with 5 items (IIEF-5 or SHIM), presents at the cutoff score of 21, a sensitivity of 98 %, a specificity of 88 % and a kappa index of 0.82. The ED is often responsible for a decrease in the quality of life for 60 % of elderly couples wishing to pursue sexual activity. Some diagnostic tools, such as the "Self-Esteem And Relationship" (SEAR) questionnaire or the "Sexual Experience Questionnaire" (SEX-Q) assess individual and couple satisfaction. Physiological aging seems to favor erection disorders by the development of an Androgen Deficiency of the Aging Male (ADAM) but pathological aging appears to be primarily responsible. Cardiovascular or neurological diseases and lower urinary tract symptoms (LUTS) are, with the polymedication, modifiable risk factors of ED to systematically screen in elderly subjects. Many diagnostic tools allow to detect ED and assess the impact on the quality of life of elderly men. The fundamental element of the management of ED is the research of modifiable risk factors including cardiovascular. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Can Ayahuasca and sleep loss change sexual performance in male rats?

Science.gov (United States)

Alvarenga, T A; Polesel, D N; Matos, G; Garcia, V A; Costa, J L; Tufik, S; Andersen, M L

2014-10-01

The ingestion of the beverage Ayahuasca usually occurs in religious ceremonies that are performed during the night leading to sleep deprivation. The purpose of the present study was to characterize the acute effects of Ayahuasca upon the sexual response of sleep deprived male rats. One group of sexually experienced male Wistar rats were submitted to a paradoxical sleep deprivation (PSD) protocol for 96h, while another group spent the same amount of time in the home cage (CTRL). After this period, either saline or Ayahuasca drink (250, 500 and 1000μgmL(-1)) was administered by gavage and sexual behavior and hormonal concentrations were measured. Ayahuasca alone significantly decreased sexual performance at all doses. However, in sleep deprived rats, the lower dose increased sexual performance while the intermediate dose produced a detrimental effect on sexual response compared to the CTRL rats at the same dose. Regarding the hormonal analyses, a lower testosterone concentration was observed in sleep-deprived saline rats in relation to the CTRL group. Progesterone was significantly lower only in PSD rats at the dose 500μgmL(-1) compared with CTRL-500μgmL(-1) group. Corticosterone was unchanged among the groups evaluated. Our results suggest that Ayahuasca intake markedly impaired sexual performance alone, but, when combined with sleep deprivation, had significant, but heterogeneous, effects on male sexual response. Copyright © 2014. Published by Elsevier B.V.

Does male circumcision affect sexual function, sensitivity, or satisfaction?--a systematic review.

Science.gov (United States)

Morris, Brian J; Krieger, John N

2013-11-01

Circumcision of males is commonly carried out worldwide for reasons of health, medical need, esthetics, tradition, or religion. Whether circumcision impairs or improves male sexual function or pleasure is controversial. The study aims to conduct a systematic review of the scientific literature. A systematic review of published articles retrieved using keyword searches of the PubMed, EMBASE, and Cochrane databases was performed. The main outcome measure is the assessment of findings in publications reporting original data relevant to the search terms and rating of quality of each study based on established criteria. Searches identified 2,675 publications describing the effects of male circumcision on aspects of male sexual function, sensitivity, sensation, or satisfaction. Of these, 36 met our inclusion criteria of containing original data. Those studies reported a total of 40,473 men, including 19,542 uncircumcised and 20,931 circumcised. Rated by the Scottish Intercollegiate Guidelines Network grading system, 2 were 1++ (high quality randomized controlled trials) and 34 were case-control or cohort studies (11 high quality: 2++; 10 well-conducted: 2+; 13 low quality: 2-). The 1++, 2++, and 2+ studies uniformly found that circumcision had no overall adverse effect on penile sensitivity, sexual arousal, sexual sensation, erectile function, premature ejaculation, ejaculatory latency, orgasm difficulties, sexual satisfaction, pleasure, or pain during penetration. Support for these conclusions was provided by a meta-analysis. Impairment in one or more parameters was reported in 10 of the 13 studies rated as 2-. These lower-quality studies contained flaws in study design (11), selection of cases and/or controls (5), statistical analysis (4), and/or data interpretation (6); five had multiple problems. The highest-quality studies suggest that medical male circumcision has no adverse effect on sexual function, sensitivity, sexual sensation, or satisfaction. © 2013

Factors related to sexual practices and successful sexually transmitted infection/HIV intervention programs for Latino adolescents.

Science.gov (United States)

Lee, Young-Me; Dancy, Barbara; Florez, Elizabeth; Holm, Karyn

2013-01-01

The purpose of this integrative literature review was to explore factors that are related to sexual practices among Latino adolescents and identify which of those factors are common across successful sexually transmitted infection (STI)/HIV intervention programs for Latino adolescents. An integrative literature review was conducted. Search terms included Latino, Hispanic, education, intervention/prevention programs, sex, sexuality, reproductive health, health risk behaviors, multiple sex partners, contraception, STI/HIV/AIDS, sexually transmitted diseases, delay in initiation of sexual intercourse, consistent use of birth control, avoidance of STI/HIV infections, unintended pregnancy, cultural factors, and gender roles. Findings revealed from the review of 17 articles addressing factors related to sexual practices among Latino adolescents included familialism, religion, gender roles, level of knowledge/information, and privacy/confidentiality. Five successful STI/HIV intervention programs, that incorporated those factors to effectively reduce risky sexual behaviors were identified. STI/HIV knowledge and gender roles were recognized as common factors integrated into and across successful intervention programs for this population. Only STI/HIV knowledge and gender roles were found as common factors across the five successful STI/HIV intervention programs and should be incorporated into future intervention programs that are culturally and gender specific. Therefore, health care providers need to understand culturally related gender roles and their impact on sexual practices to provide culturally sensitive and appropriate sex education about STIs and HIV for Latino adolescents to increase the program potential for reducing STI/HIV. © 2013 Wiley Periodicals, Inc.

Sexual health knowledge, sexual relationships and condom use among male trekking guides in Nepal: a qualitative study.

Science.gov (United States)

Simkhada, Padam; van Teijlingen, Edwin R; Regmi, Pramod R; Bhatta, Prakash

2010-01-01

People in Nepal generally hold fairly traditional views about sex and sexual health, whilst Western tourists often have a more liberal approach towards sex and relationships. There is evidence that significant sexual interaction occurs between male trekking guides and female travellers and/or local female sex workers in Nepal. This qualitative study explored trekking guides' sexual health knowledge, sexual relationships and condom use with female trekkers and local female sex workers. A total of 21 in-depth interviews were conducted with male trekking guides. Most reported having had sexual relationships with female trekkers and local female sex workers. Explanations for intercourse with female trekkers included: financial support; getting future trekkers through word-of-mouth advertising from the women they have had sex with; and opportunities for emigration. Interestingly, sexual intercourse is reported as more likely to be initiated by female trekkers than by guides, and more so by older women. In contrast, the main reasons for having sex with local female sex workers included: romantic love or sexual excitement and novelty. Awareness regarding sexual health was high among guides, but several factors discouraged the regular use of condoms. Further research with female tourists would help understand the motivations and reasons for their sexual behaviour.

A Meta-Analysis of Risky Sexual Behaviour among Male Youth in Developing Countries

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Yifru Berhan

2015-01-01

Full Text Available The purpose of this meta-analysis was to assess the association between risky sexual behaviour and level of education and economic status in male youth. Previous tests of the association of risky sexual behaviour with levels of education and economic status have yielded inconsistent results. Using data from 26 countries, from both within and outside Africa, we performed a meta-analysis with a specific focus on male youths’ risky sexual behaviour. We applied a random effects analytic model and calculated a pooled odds ratio. Out of 19,148 males aged 15–24 years who reported having sexual intercourse in the 12 months preceding the survey, 75% engaged in higher-risk sex. The proportion of higher-risk sex among male youth aged 15–19 years was nearly 90% in 21 of the 26 countries. The pooled odds ratio showed a statistically significant association of higher-risk sex with male youth younger than 20 years, living in urban centers, well educated, and of a high economic status. The overall proportion of condom use during youths’ most recent higher-risk sexual encounter was 40% and 51% among 15–19-year-olds and 20–24-year-olds, respectively. Our findings suggest that male youth’s socioeconomic status is directly related to the likelihood that they practice higher-risk sex. The relationship between income and sexual behaviour should be explored further.

Immune activation affects chemical sexual ornaments of male Iberian wall lizards

Science.gov (United States)

López, Pilar; Gabirot, Marianne; Martín, José

2009-01-01

Many animals use chemical signals in sexual selection, but it is not clear how these sexual traits might have evolved to signal honestly male condition. It is possible that there is a trade-off between maintaining the immune system and the elaboration of ornaments. We experimentally challenged the immune system of male Iberian wall lizards, Podarcis hispanica, with a bacterial antigen (lipopolysaccharide), without pathogenic effects, to explore whether the immune activation affected chemical ornaments. Immune activation resulted in decreased proportions of a major chemical in femoral secretions (cholesta-5,7-dien-3-ol = provitamin D3) known to be selected in scent of males by females and which active form (vitamin D) has a variety of important effects on immune system function. This result suggests the existence of a potential trade-off between physiological regulation of the immune system and the allocation of essential nutrients (vitamins) to sexual chemical ornaments in male lizards.

[Psycho-social factors of sexual failure among newly married Uyghur young males].

Science.gov (United States)

Erkin, Ashim; Hamrajan, Memtili; Kadirjan, Mijit; Adil, Eli; Elijan, Abdureshit; Ibrahim, Ubul; Abdulla, Tursun; Hasanjan, Abdurehim; Turgun, Hekim; Eli, Ablet; Eset, Metmusa

2016-08-01

To study the psycho-social risk factors of sexual failure among newly married young males in the Uyghur population. We conducted a paired case control study of 186 newly married Uyghur young males (aged 17－30 ［23.4±2.9］ yr) with sexual failure and another 186 (aged 18－34 ［24.0±3.1］ yr) with no such problem as controls. We performed a logistic regression analysis on the possible psycho-social risk factors of this condition. Logistic regression analysis showed that the risk factors of sexual failure among the newly married men included personality (OR=0.271, 95% CI 0.176－0.420), income (OR=0.391, 95% CI 0.264－0.580), history of masturbation (OR=0.824, 95% CI 0.710－0.956), premarital sex (OR=0.757, 95% CI 0.677－0.847), sense of obligation (OR=1.756, 95% CI 1.157－2.693), equality of the social status (OR=0.574, 95% CI 0.435－0.756), degree of mutual care (OR=1.605, 95% CI 1.268－2.032), female's psychological obstacle (OR=2.832, 95% CI 1.221－6.569), and religion (OR=0.643, 95% CI 0.472－0.967). There was a statistical significance in the correlation between these factors and sexual failure in the newly married males (all Ppsycho-social factors, which necessitates sexual education among young males and particularly pre-marriage sexual education and psychological guide among both males and females.

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

Science.gov (United States)

Dadda, Marco

2015-01-01

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

Female social response to male sexual harassment in poeciliid fish: A comparison of six species

Directory of Open Access Journals (Sweden)

Marco eDadda

2015-09-01

Full Text Available Sexual harassment is common among poeciliid fish. In some fishes, males show a high frequency of sneak copulation; such sexual activity is costly to the females in terms of foraging efficiency. In mosquitofish (Gambusia holbrooki, when males are present, the distance between females tends to decrease, and this behavior has been interpreted as an adaptive strategy to dilute the costs of male sexual activity. In this study, the tendency to reduce distance in the presence of a male has been investigated in females of 6 poeciliid species (Girardinus metallicus, Girardinus falcatus, Gambusia holbrooki, Poecilia reticulata, Xiphophorus hellerii and Xiphophorus mayae that exhibit different male mating strategies and different levels of sexual activity. Results revealed large interspecific differences in the pattern of female aggregation. Females of species with a high frequency of sneak copulations tended to reduce their social distance in the presence of a male. By contrast, species that rely mainly on courtship showed little or no variation in social distance. The proportion of sneak copulations predicts the degree of variation in female social response, but the amount of total sexual activity does not, suggesting that the change in females’ social distance when a male is present may indeed serve to reduce the costs of male sexual harassment.

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

Science.gov (United States)

Dadda, Marco

2015-01-01

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

Methylmercury Exposure Induces Sexual Dysfunction in Male and Female Drosophila Melanogaster.

Science.gov (United States)

Chauhan, Ved; Srikumar, Syian; Aamer, Sarah; Pandareesh, Mirazkar D; Chauhan, Abha

2017-09-24

Mercury, an environmental health hazard, is a neurotoxic heavy metal. In this study, the effect of methylmercury (MeHg) exposure was analyzed on sexual behavior in Drosophila melanogaster (fruit fly), because neurons play a vital role in sexual functions. The virgin male and female flies were fed a diet mixed with different concentrations of MeHg (28.25, 56.5, 113, 226, and 339 µM) for four days, and the effect of MeHg on copulation of these flies was studied. While male and female control flies (no MeHg) and flies fed with lower concentrations of MeHg (28.25, 56.5 µM) copulated in a normal manner, male and female flies exposed to higher concentrations of MeHg (113, 226, and 339 µM) did not copulate. When male flies exposed to higher concentrations of MeHg were allowed to copulate with control female flies, only male flies fed with 113 µM MeHg were able to copulate. On the other hand, when female flies exposed to higher concentrations of MeHg were allowed to copulate with control male flies, none of the flies could copulate. After introduction of male and female flies in the copulation chamber, duration of wing flapping by male flies decreased in a MeHg-concentration-dependent manner from 101 ± 24 seconds (control) to 100.7 ± 18, 96 ±12, 59 ± 44, 31 ± 15, and 3.7 ± 2.7 seconds at 28.25, 56.5, 113, 226, and 339 µM MeHg, respectively. On the other hand, grooming in male and female flies increased in a MeHg-concentration-dependent manner. These findings suggest that MeHg exposure causes sexual dysfunction in male and female Drosophila melanogaster . Further studies showed that MeHg exposure increased oxidative stress and decreased triglyceride levels in a concentration-dependent manner in both male and female flies, suggesting that MeHg-induced oxidative stress and decreased triglyceride levels may partly contribute to sexual dysfunction in fruit flies.

Sexually Explicit Media on the Internet: A Content Analysis of Sexual Behaviors, Risk, and Media Characteristics in Gay Male Adult Videos

OpenAIRE

Downing, Martin J.; Schrimshaw, Eric W.; Antebi, Nadav; Siegel, Karolynn

2013-01-01

Recent research suggests that viewing sexually explicit media (SEM), i.e., adult videos, may influence sexual risk taking among men who have sex with men (MSM). Despite this evidence, very little is known about the content of gay male SEM on the Internet, including the prevalence of sexual risk behaviors and their relation to video- and performer-characteristics, viewing frequency, and favorability. The current study content analyzed 302 sexually explicit videos featuring male same-sex perfor...

Inbreeding affects sexual signalling in males but not females of Tenebrio molitor.

Science.gov (United States)

Pölkki, Mari; Krams, Indrikis; Kangassalo, Katariina; Rantala, Markus J

2012-06-23

In many species of animals, individuals advertise their quality with sexual signals to obtain mates. Chemical signals such as volatile pheromones are species specific, and their primary purpose is to influence mate choice by carrying information about the phenotypic and genetic quality of the sender. The deleterious effects of consanguineous mating on individual quality are generally known, whereas the effect of inbreeding on sexual signalling is poorly understood. Here, we tested whether inbreeding reduces the attractiveness of sexual signalling in the mealworm beetle, Tenebrio molitor, by testing the preferences for odours of inbred and outbred (control) individuals of the opposite sex. Females were more attracted to the odours produced by outbred males than the odours produced by inbred males, suggesting that inbreeding reduces the attractiveness of male sexual signalling. However, we did not find any difference between the attractiveness of inbred and outbred female odours, which may indicate that the quality of females is either irrelevant for T. molitor males or quality is not revealed through female odours.

Masturbation and its relationship to sexual activities of young males in Korean military service.

Science.gov (United States)

Choi, Y J; Lee, W H; Rha, K H; Xin, Z C; Choi, Y D; Choi, H K

2000-04-01

This study examined the masturbatory experiences and other sexual activities of young Korean males in military service. The actual status of masturbation and its relationship to sexual activity questionnaire. A total of 1,212 young males among military personnel in Korea were interviewed with sexuality questionnaires on masturbation, sexual intercourse and personal characteristics. We divided these subjects into four groups according to the age of initiation of masturbation and analyzed the relationship between masturbation and other sexual activities. The mean age of subjects was 22.03 +/- 1.22 (19-27) years. The percentage of men who reported ever having masturbated was 98.1% (1189/1212) and the average age of initiation of masturbation was 14.26 +/- 1.66 years. So we divided 1,212 males into four groups on the basis of the average age below and above one standard deviation. Overall, 67.7% (821/1212) had experienced sexual intercourse, and significantly, the earlier the initiation age of masturbation, the higher the coitus rate in each group (p masturbation were closely linked to the initiation age of masturbation, respectively (p masturbation was earlier. Coital incidence in this study was 67.7% for young males in Korean military service, and 21.5% of them had their first sexual intercourse with prostitutes. Prostitution still plays an important role in the sexual lives of males in Korea. The incidence of STD was over 10% and homosexual manifestation was seen in 1.07% of subjects. Thus a proper and sound sex education at school during childhood is needed in Korea. A large scale survey of sexual behavior in various populations is essential for the improvement of correct sexual concepts.

Attachment and personality predicts engagement in sexual harassment by male and female college students.

Science.gov (United States)

Mènard, Kim S; Shoss, Naomi E; Pincus, Aaron L

2010-01-01

The purpose of this study was to examine a trait model of personality (Five-Factor Model) as a mediator of the relationship between attachment styles and sexually harassing behavior in a sample of male (N = 148) and female (N = 278) college students. We found that gender (male) and low Agreeableness predicted engaging in sexual harassment and all three of its subtypes; gender harassment, unwanted sexual attention, and sexual coercion. Further, low Conscientiousness predicted overall sexual harassment, gender harassment, and unwanted sexual attention. Personality traits mediated the relationship between insecure attachment styles (Preoccupation with Relationships and Relationships as Secondary) and sexually harassing behaviors. Thus, factors beyond gender can help predict students' propensity to sexually harass others.

Sexual cannibalism in the garden spider Araneus diadematus

DEFF Research Database (Denmark)

Elgar, Mark A.; Nash, David Richard

1988-01-01

In natural populations, courting males of Araneus diadematus are often consumed by females before they have successfully copulated. Despite the possible nutritional benefits of sexual cannibalism for females, the male can derive no benefit by being consumed before copulation. In this study, females...... that consumed a single male significantly increased their body mass, regardless of the quality of their diet. The implication is that, for A. diadematus, sexual cannibalism increases female fecundity. In experimentally controlled courtship sequences, larger males were less likely to be cannibalized than smaller...... males, but female size had no effect on male mating success. The mating success of males was not influenced by the age of the male, indicating that cannibalism is not the result of male senility....

Sexpectations: male college students' views about displayed sexual references on females' social networking web sites.

Science.gov (United States)

Moreno, Megan A; Swanson, Michael J; Royer, Heather; Roberts, Linda J

2011-04-01

Sexual reference display on a social networking web site (SNS) is associated with self-reported sexual intention; females are more likely to display sexually explicit content on SNSs. The purpose of this study was to investigate male college students' views towards sexual references displayed on publicly available SNSs by females. Focus groups. One large state university. Male college students age 18-23. All tape recorded discussion was fully transcribed, then discussed to determine thematic consensus. A trained male facilitator asked participants about views on sexual references displayed on SNSs by female peers and showed examples of sexual references from female's SNS profiles to facilitate discussion. A total of 28 heterosexual male participants participated in seven focus groups. Nearly all participants reported using Facebook to evaluate potential female partners. Three themes emerged from our data. First, participants reported that displays of sexual references on social networking web sites increased sexual expectations. Second, sexual reference display decreased interest in pursuing a dating relationship. Third, SNS data was acknowledged as imperfect but valuable. Females who display sexual references on publicly available SNS profiles may be influencing potential partners' sexual expectations and dating intentions. Future research should examine females' motivations and beliefs about displaying such references and educate women about the potential impact of these sexual displays. Copyright © 2011 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

The Influence of Sexual Orientation on the Perceived Fit of Male Applicants for Both Male- and Female-Typed Jobs

Directory of Open Access Journals (Sweden)

Heather M. Clarke

2018-05-01

Full Text Available Research demonstrates the bias faced by individuals engaged in occupations that are perceived as inconsistent with their gender. The lack of fit model and role congruity theory explain how gender stereotypes give rise to the perception that an individual lacks the attributes necessary to be successful in a gender-incongruent job. Men employed in jobs traditionally held by women are perceived as wimpy and undeserving of respect. The majority of studies in this area have, however, failed to account for the sexual orientation of the individual being rated. Therefore, we carried out an experiment where 128 adults with experience in recruitment and selection, recruited through Qualtrics, rated heterosexual and gay male applicants applying for a gender-typed job. The heterosexual male was rated less effectual, less respect-worthy, and less hirable in the female-typed job condition than in the male-typed job condition. The gay male applicant, however, was rated similarly on all criteria across job gender-types, suggesting the gay male applicant was viewed as androgynous rather than high in femininity and low in masculinity as inferred by implicit inversion theory. The implications of these findings are discussed.

The Influence of Sexual Orientation on the Perceived Fit of Male Applicants for Both Male- and Female-Typed Jobs.

Science.gov (United States)

Clarke, Heather M; Arnold, Kara A

2018-01-01

Research demonstrates the bias faced by individuals engaged in occupations that are perceived as inconsistent with their gender. The lack of fit model and role congruity theory explain how gender stereotypes give rise to the perception that an individual lacks the attributes necessary to be successful in a gender-incongruent job. Men employed in jobs traditionally held by women are perceived as wimpy and undeserving of respect. The majority of studies in this area have, however, failed to account for the sexual orientation of the individual being rated. Therefore, we carried out an experiment where 128 adults with experience in recruitment and selection, recruited through Qualtrics, rated heterosexual and gay male applicants applying for a gender-typed job. The heterosexual male was rated less effectual, less respect-worthy, and less hirable in the female-typed job condition than in the male-typed job condition. The gay male applicant, however, was rated similarly on all criteria across job gender-types, suggesting the gay male applicant was viewed as androgynous rather than high in femininity and low in masculinity as inferred by implicit inversion theory. The implications of these findings are discussed.

How Sexual Orientation and Physical Attractiveness Affect Impressions of Males.

Science.gov (United States)

Elman, Donald; And Others

Stereotyped impressions of male homosexuals and the underlying importance of sexuality in social attraction and perceptions were investigated. Male (N=80) and female (N=80) college students responded to either an attractive or an unattractive photo of a male stimulus person, who was identified to half of the subjects as a homosexual. Compared to…

Sexual activity increases the number of newborn cells in the accessory olfactory bulb of male rats.

Directory of Open Access Journals (Sweden)

Wendy ePortillo

2012-07-01

Full Text Available In rodents, sexual behavior depends on the adequate detection of sexually relevant stimuli. The olfactory bulb (OB is a region of the adult mammalian brain undergoing constant cell renewal by continuous integration of new granular and periglomerular neurons in the accessory (AOB and main (MOB olfactory bulbs. The proliferation, migration, survival, maturation, and integration of these new cells to the OB depend on the stimulus that the subjects received. We have previously shown that 15 days after females control (paced the sexual interaction an increase in the number of cells is observed in the AOB. No changes are observed in the number of cells when females are not allowed to control the sexual interaction. In the present study we investigated if in male rats sexual behavior increases the number of new cells in the OB. Male rats were divided in five groups: 1 males that did not receive any sexual stimulation, 2 males that were exposed to female odors, 3 males that mated for 1 h and could not pace their sexual interaction, 4 males that paced their sexual interaction and ejaculated 1 time and 5 males that paced their sexual interaction and ejaculated 3 times. All males received three injections of the DNA synthesis marker bromodeoxyuridine at 1h intervals, starting 1h before the beginning of the behavioral test. Fifteen days later, males were sacrificed and the brains were processed to identify new cells and to evaluate if they differentiated into neurons. The number of newborn cells increased in the granular cell layer (also known as the internal cell layer of the AOB in males that ejaculated one or three times controlling (paced the rate of the sexual interaction. Some of these new cells were identified as neurons. In contrast, no significant differences were found in the mitral cell layer (also known as the external cell layer and glomerular cell layer of the AOB. In addition, no significant differences were found between groups in the MOB in

Biological and psychosocial determinants of male and female human sexual orientation.

Science.gov (United States)

James, William H

2005-09-01

Some propositions on male and female sexual orientation will be considered. Some of these are established; others are more speculative. The aim is to offer some notes towards a coherent, comprehensive theory of sexual orientation. 1. The distinction between butch and femme lesbians seems real rather than a social construct. 2. High levels of prenatal steroid hormones seem to be causally associated with the sexual orientation of butch lesbians. However it is not established whether the causal process operates prenatally or postnatally (or both). This is so because prenatal hormone levels are thought to correlate positively with postnatal hormone levels. And high postnatal hormone levels may facilitate homosexual behaviour as a consequence of sensation-seeking. 3. Male bisexuals also are interpreted to have been exposed to high prenatal testosterone levels. But (for reasons similar to those outlined above in regard to butch lesbians) it is unclear whether these have a direct prenatal effect on the brain or whether they are precursors of high postnatal testosterone levels, which are associated with male bisexual orientation by promoting sensation-seeking behaviour. 4. Postnatal learning processes seem to be causally involved in the sexual orientation of some femme lesbians and some exclusive male homosexuals. 5. Some homosexual men have genes that predispose to their sexual orientation. 6. The same may apply to some lesbians, but such genes have not, as far as I know, been identified. 7. People (of both sexes) who engage in same-sex sexual behaviour may be classified simultaneously in two ways, viz (1) 'active' vs 'passive' and (2) those who do and those who do not engage (or consider engaging) in sex with members of the opposite sex. Ex hypothesi, some of the 'active' ones initiate some of the 'passive' ones. The active ones are driven more by hormones and the passive ones by psychosocial factors. The active males contain a substantial proportion of self

The role of the dorsolateral tegmentum in the control of male sexual behavior: a reevaluation.

Science.gov (United States)

Romero-Carbente, J C; Camacho, F J; Paredes, R G

2006-06-30

The medial preoptic area/anterior hypothalamus (MPOA/AH) plays a key role in the control of male sexual behavior. Independently of the type, MPOA/AH lesions permanently eliminate male sexual behavior in the rat. The MPOA/AH projects among other structures to the dorsolateral tegmentum (DLT). Bilateral electrolytic lesions of the DLT or the unilateral electrolytic destruction of the MPOA/HA combined with a contralateral electrolytic lesion of the DLT eliminate male sexual behavior. In the present experiment, we evaluated if neurotoxic lesions of the DLT produce the same behavioral deficits as those observed after electrolytic lesions. This would allow us to evaluate if neurons of the DLT or the fibers passing through this area are important in the control of male sexual behavior. To this aim, sexually experience male rats were tested for socio-sexual behavior, partner preference and motor execution in order to determine if the possible behavioral changes could be attributed to alterations in sexual motivation or motor execution. One week after the bilateral DLT lesions the animals were evaluated in the same behavioral tests. The lesions were identified by glial fibrillary acidic protein (GFAP) and neuronal nuclear protein (Neu-N) immunohistochemistry. No significant consistent effects upon sexual behavior were observed in any of the groups, including the group with clear bilateral damage of the DLT. A reduction in the percentage of males displaying ejaculation in the first post-lesion test was observed for all groups injected with quinolinic acid. No effects upon partner preference or motor coordination were observed after the lesion in any of the groups. The lack of effect of DLT neurotoxic lesions upon mating suggests that neurons of this structure are not involved in the control of male sexual behavior.

Predictors of sexual bother in a population of male North American medical students.

Science.gov (United States)

Smith, James F; Breyer, Benjamin N; Shindel, Alan W

2011-12-01

The prevalence and associations of sexual bother in male medical students has not been extensively studied. The aim of this study is to analyze predictors of sexual bother in a survey of male North American medical students. Students enrolled in allopathic and osteopathic medical schools in North America between February 2008 and July 2008 were invited to participate in an internet-based survey of sexuality and sexual function. The principle outcome measure was a single-item question inquiring about global satisfaction with sexual function. The survey also consisted of a questionnaire that included ethnodemographic factors, student status, sexual history, and a validated scale for the assessment of depression. Respondents completed the International Index of Erectile Function, the premature ejaculation diagnostic tool, and the Self-Esteem and Relationship Quality survey (SEAR). Descriptive statistics, analysis of variance, and multivariable logistic regression were utilized to analyze responses. There were 480 male subjects (mean age 26.3 years) with data sufficient for analysis. Forty-three (9%) reported sexual bother. Sexual bother was significantly more common in men with erectile dysfunction (ED), high risk of premature ejaculation (HRPE), depressive symptoms, and lower sexual frequency. However, after multivariate analysis including SEAR scores, ED, and HRPE were no longer independently predictive of sexual bother. Higher scores for all domains of the SEAR were associated with lower odds of sexual bother. ED and HRPE are associated with sexual bother in this young and presumably healthy population. However, after controlling for relationship factors neither ED nor HRPE independently predicted sexual bother. It is plausible to hypothesize that sexual dysfunction from organic causes is rare in this population and is seldom encountered outside of relationship perturbations. Attention to relationship and psychological factors is likely of key importance in

Men's constructions of masculinity and male sexuality through talk of buying sex.

Science.gov (United States)

Huysamen, Monique; Boonzaier, Floretta

2015-01-01

Commercial sex is an everyday occurrence across a range of contexts in South Africa. In this paper we turn our attention to the often-marginalised role of the buyers of sex by drawing on narrative interviews with male clients of female sex workers recruited through online advertisements in order to explore the ways in which heterosexual men construct, negotiate and perform their masculinity and sexuality through talking about their experiences of paying for sex. We highlight parallels between men's narratives of paying for sex and dominant discourses of gender and heterosexuality. We show how men draw on heteronormative sexual scripts in constructing and making sense of paid sexual encounters and how men are simultaneously able to construct and enact a particular idealised version of masculinity and male sexuality through their talk on paying for sex. Finally, we discuss how online resources could be used more extensively in future research with the male clients of sex workers.

[Age-related aspects of male rats sexual behavior with different senescence rates].

Science.gov (United States)

Amstislavskaia, T G; Gladkikh, D V; Belousova, I I; Maslova, L N; Kolosova, N G

2010-01-01

Social and sexual behavior of males Wistar and senescence-accelerated OXYS rats was studied. The experimental model excluding direct interaction between partners showed that the exploratory activity decreased with aging in rats of both strains, but social motivation didn't change. No interstrain differences in intensity of sexual motivation in the presence of an inaccessible receptive female were observed in 4-month rats. The level of sexual motivation of 12-month Wistar rats didn't differ from that of 4-month animals. However, in 12-month OXYS males, sexual motivation was decreased as compared to both 4- and 12-month Wistar rats. The same regularities were found under conditions of direct interaction with a partner. Behavioral changes in 12-month OXYS rats were considered as genetically determinate abnormality at the initial stage of sexual behavior, i.e., sexual motivation. The results suggest the accelerated senescence of the reproductive system of OXYS rats.

Male sexual polymorphism, alternative reproductive tactics, and androgens in combtooth blennies (pisces: blenniidae).

Science.gov (United States)

Oliveira, R F; Canario, A V; Grober, M S

2001-09-01

In species in which intense intermale competition for the access to females is present males of lower competitive ability may adopt alternative reproductive tactics (ART) to get access to mates. These ART translate in many cases into male sexual polymorphism, with individuals following distinctly different tactics. Usually two alternative male morphs can be recognized in species with ART: (1) bourgeois males that compete for access to mates invest in typically male behaviors, such as building elaborated nests or displaying ornaments; and (2) parasitic males that take advantage of the success of the bourgeois males in attracting females and attempt "sneaker" fertilizations (e.g., sneaker and satellite males). In combtooth blennies (Blenniidae) the co-occurrence of ART and male sexual polymorphism has been described for two temperate species: the peacock blenny, Salaria pavo, and the Azorean rock-pool blenny, Parablennius sanguinolentus parvicornis. Interestingly, while in the peacock blenny the alternative male morph adopts a sneaker tactic, in the rock-pool blenny parasitic males act as satellites to nest-holder males. Thus, this variation in the ART expressed in these two closely related species allows for a comparative study of the proximate and ultimate factors affecting the expression of the two ART. In this article we summarize the available information on androgen levels in bourgeois and parasitic males of natural populations of the two species and of recent studies on the effect of exogenous administration of androgens on tactic switching in parasitic males of the two species. The information is discussed within the frame of the relative plasticity hypothesis, which predicts that plastic alternative morphs should show differences in hormone levels and that the administration of sex steroids should be effective in promoting the switch from the parasitic to bourgeois tactic. The evidence is only partly consistent with this hypothesis. Alternatively, a social

Sexual function of male rats exposed to the factors of the Chernobyl exclusion zone

International Nuclear Information System (INIS)

Karpenko, N.A.

2000-01-01

Using sexually active rats for experiments the influence of chronic combined internal and external irradiation at low doses on sexual behavior and fertility of sexual active animals keeping within the 30-km Chernobyl external zone studied. After the 1.5 month consumption of drinking water containing radionuclides of natural Chernobyl spectrum the decrease in proportion of sexually active animals and suppression sexual motivation and erection were observed. This deviations resulted in the reducing of the inseminated females number. Dependence between the magnitude of total absorbed dose and the function of the sexual behavior regulatory mechanisms was obtained. In addition, the reduction of rat fertility took place because of the increase of preimplantation, but not post-implantation death in clean females coupled with irradiated males. Irradiation of males at total absorbed dose to gonads 0.23 c Gy decreased the fertility because of sexual behavior disturbance, and this effect was intensified by negative influence of ionizing radiation in the range of 0.7-7.0 c Gy on male gametes [ru

International spinal cord injury male sexual function and female sexual and reproductive function basic data sets-version 2.0

DEFF Research Database (Denmark)

Alexander, Marcalee S; New, Peter W; Biering-Sørensen, Fin

2017-01-01

S Scientific and Executive Committees and ASIA board of directors. RESULTS: The data sets were modified to a self-report format. They were reviewed for appropriateness for the pediatric age group and adapted to include a new variable to address the issue of sexual orientation. A clarification of the difference......STUDY DESIGN: Data set review and modification. OBJECTIVE: To describe modifications in the International Spinal Cord Injury (SCI) Male Sexual Function Basic Data Set Version 2.0 and the International SCI Female Sexual and Reproductive Function Basic Data Set Version 2.0. SETTING: International...... expert work group using on line communication. METHODS: An international team of experts was compiled to review and revise the International SCI Male Sexual Function and Female Sexual and Reproductive Function Basic Data Sets Version 1.0. The group adapted Version 1.0 based upon review of published...

A new role for GABAergic transmission in the control of male rat sexual behavior expression.

Science.gov (United States)

Rodríguez-Manzo, Gabriela; Canseco-Alba, Ana

2017-03-01

GABAergic transmission in the ventral tegmental area (VTA) exerts a tonic inhibitory influence on mesolimbic dopaminergic neurons' activity. Blockade of VTA GABA A receptors increases dopamine release in the nucleus accumbens (NAcc). Increases in NAcc dopamine levels typically accompany sexual behavior display. Copulation to satiety is characterized by the instatement of a long lasting (72h) sexual behavior inhibition and the mesolimbic system appears to be involved in this phenomenon. GABAergic transmission in the VTA might play a role in the maintenance of this long lasting sexual inhibitory state. To test this hypothesis, in the present work we investigated the effect of GABA A receptor blockade in sexually exhausted males 24h after copulation to satiety, once the sexual inhibitory state is established, and compared it with its effect in sexually experienced rats. Results showed that low doses of systemically administered bicuculline induced sexual behavior expression in sexually exhausted rats, but lacked an effect on copulation of sexually experienced animals. Intra-VTA bilateral infusion of bicuculline did not modify sexual behavior of sexually experienced rats, but induced sexual behavior expression in all the sexually exhausted males. Hence, GABA plays a role in the control of sexual behavior expression at the VTA. The role played by GABAergic transmission in male sexual behavior expression of animals with distinct sexual behavior conditions is discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

Status and Mating Success Amongst Visual Artists

Science.gov (United States)

Clegg, Helen; Nettle, Daniel; Miell, Dorothy

2011-01-01

Geoffrey Miller has hypothesized that producing artwork functions as a mating display. Here we investigate the relationship between mating success and artistic success in a sample of 236 visual artists. Initially, we derived a measure of artistic success that covered a broad range of artistic behaviors and beliefs. As predicted by Miller’s evolutionary theory, more successful male artists had more sexual partners than less successful artists but this did not hold for female artists. Also, male artists with greater artistic success had a mating strategy based on longer term relationships. Overall the results provide partial support for the sexual selection hypothesis for the function of visual art. PMID:22059085

The adrenergic alpha2 receptor and sexual incentive motivation in male rats.

Science.gov (United States)

Viitamaa, Timo; Haapalinna, Antti; Agmo, Anders

2006-03-01

The purpose of the present series of experiments was to determine whether drugs acting at the alpha2-adrenoceptor modify unconditioned sexual incentive motivation in the male rat. To that end a highly specific agonist, dexmedetomidine, a corresponding antagonist, atipamezole, and a less specific antagonist, yohimbine, were administered to groups of sexually inexperienced male rats. The subjects were tested in a large rectangular arena, where a sexually receptive female and an intact male were employed as incentives. The incentive animals were confined behind a wire mesh in opposite corners of the arena. The animals could see, hear and smell each other, but no sexual interaction was possible. Approach to the incentives constituted the measure of incentive motivation. In addition, the test provided data on ambulatory activity and general arousal. Dexmedetomidine, at a dose of 8 microg/kg, produced a slight reduction of sexual incentive motivation. Ambulatory activity and general arousal were also inhibited. Atipamezole, in doses of 0.1 and 0.3mg/kg enhanced the positive incentive properties of the receptive female. A high dose of 1mg/kg did not have any significant effect. Ambulatory activity was slightly reduced by the two larger doses of atipamezole. Yohimbine had a slight stimulatory effect on sexual incentive motivation at a dose (4 mg/kg) that also reduced ambulatory activity and general arousal. It is concluded that blockade of the adrenergic alpha2 receptor stimulates sexual incentive motivation in the male rat whereas stimulation of it has the opposite effect. At present it is not clear if these drug effects are caused by pre- or postsynaptic actions of the drugs, and the importance of secondary changes in other neurotransmitter systems remains unknown.

The impact of parenting on gay male couples' relationships, sexuality, and HIV risk

Science.gov (United States)

Huebner, David M.; Mandic, Carmen Gómez; Mackaronis, Julia E.; Beougher, Sean C.; Hoff, Colleen C.

2014-01-01

Parenthood changes couples' relationships across multiple domains, generally decreasing relationship quality, sexual satisfaction, and sexual frequency. Emerging research suggests that gay couples who are parenting might experience similar challenges. However, such changes might have even more profound implications for gay couples' health, and in particular their HIV risk, given the somewhat different ways in which they negotiate and tolerate sexual behaviors with outside partners. We aimed to examine these issues in a qualitative analysis of interviews from 48 gay male couples who were actively parenting children. Findings suggest that parenthood increases men's commitment to their primary relationship while simultaneously decreasing time and energy for relationship maintenance, and generally decreasing sexual satisfaction. These challenges alone did not generally result in greater infidelity or HIV risk, as most men reported successfully coping with such changes through a combination of acceptance and revaluing what is important in their relationships. Additionally, couples reported negotiating agreements regarding sex with outside partners that closely resemble those documented in studies of gay couples who are not parents. Men reported that parenthood typically decreased their opportunities to engage in sex with outside partners, but also posed barriers to talking about these behaviors with their partners and healthcare providers. HIV-related sexual risk behavior was relatively rare, but nevertheless present in some men. Providers should assess sexual function as a regular part of their work with gay couples who parent, and facilitate opportunities for men to discuss their sexual agreements both with their primary partners and with relevant healthcare providers. PMID:25674355

Surgical Procedures for BPH/LUTS: Impact on Male Sexual Health.

Science.gov (United States)

Becher, Edgardo F; McVary, Kevin T

2014-01-01

Lower urinary tract symptoms (LUTS) because of benign prostatic hyperplasia (BPH) are a highly prevalent condition in men over 50 years old, and their incidence increases with age. The relationship between LUTS and erectile dysfunction (ED) has received increased attention recently because both diseases are highly prevalent, frequently co-associated in the same aging male group, and contribute significantly to the overall quality of life. In this review, we will examine the literature to assess the impact of surgical and minimally invasive treatments for LUTS/BPH on the male's sexual health. The impact of the various surgical and minimally invasive treatments for LUTS/BPH was reviewed to ascertain the impact on erectile and ejaculatory function. Sexual side effects of treatment for LUTS/BPH are underappreciated by urologists but likely play a prominent role in patient decision making, creating a disparity between provider and patient. Almost all accepted therapies for LUTS (surgical or medical) can affect some aspect of sexual health, making it imperative that health-care professionals understand their patients' concerns and motivations in these two linked diseases. The incidence of newly diagnosed postoperative ED in patients treated with monopolar transurethral resection (TURP) is around 14%, with reported values in various studies ranging from 0-32.5%, 7.7%, 6.5%, 17%, to 14%. Importantly, there is no significant difference reported between bipolar and monopolar TURP on sexual function. The risk of sexual side effects is an important one to consider in discussing the implications for any LUTS intervention as they play a prominent role in patient motivation, acceptance of bother and decision making concerning surgical intervention, thus creating a potential disparity between provider and patient. Becher EF and McVary KT. Surgical procedures for BPH/LUTS: Impact on male sexual health. Sex Med Rev 2014;2:47-55. Copyright © 2014 International Society for Sexual

Toward improved interpretation and theory building of African American male sexualities.

Science.gov (United States)

Lewis, Linwood J; Kertzner, Robert M

2003-11-01

This paper examined five challenges to clear understanding of African American male sexualities: incorrect assumptions of African American homogeneity; an underemphasis on developmental change, the contexts and the meanings of sexual behaviors; and a lack of compelling theoretical grounding for African American sexualities. Critical elements for effective theorizing and research about African American sexualities (i.e. multiple levels of analysis, examination of phenomenological meaning of sexuality, measurement of dynamic/developmental change) were outlined and candidate theories within sexual science (social exchange theories, symbolic interactionism, sexual scripting theory) were analyzed in light of these elements. It is suggested that a re-orientation of sex research about African American men using these elements will result in improved understanding of African American sexualities in multiple contexts.

Influences of dopamine and glutamate in the medial preoptic area on male sexual behavior.

Science.gov (United States)

Will, Ryan G; Hull, Elaine M; Dominguez, Juan M

2014-06-01

Several brain nuclei interact to orchestrate the appetitive and consummatory aspects of male sexual behavior. Of these structures, the medial preoptic area (mPOA) of the hypothalamus is of particular interest, as it receives input from all sensory modalities, and damage to this region disrupts copulation in a wide variety of taxa. Furthermore, the mPOA is both responsive to gonadal hormones and involved in endocrine regulation. Neurochemical studies have demonstrated that both dopamine and glutamate levels rise in the mPOA in response to sexual activity, while antagonism of these neurotransmitters impairs male sexual response. Here we review how dopamine and glutamate act in the mPOA to modulate male sexual behavior. Copyright © 2014 Elsevier Inc. All rights reserved.

Sexually explicit media on the internet: a content analysis of sexual behaviors, risk, and media characteristics in gay male adult videos.

Science.gov (United States)

Downing, Martin J; Schrimshaw, Eric W; Antebi, Nadav; Siegel, Karolynn

2014-05-01

Recent research suggests that viewing sexually explicit media (SEM), i.e., adult videos, may influence sexual risk taking among men who have sex with men. Despite this evidence, very little is known about the content of gay male SEM on the Internet, including the prevalence of sexual risk behaviors and their relation to video- and performer-characteristics, viewing frequency, and favorability. The current study content analyzed 302 sexually explicit videos featuring male same-sex performers that were posted to five highly trafficked adult-oriented websites. Findings revealed that gay male SEM on the Internet features a variety of conventional and nonconventional sexual behaviors. There was a substantial prevalence of unprotected anal intercourse (UAI) (34 %) and was virtually the same as the prevalence of anal sex with a condom (36 %). The presence of UAI was not associated with video length, amateur production, number of video views, favorability, or website source. However, the presence of other potentially high-risk behaviors (e.g., ejaculation in the mouth, and ejaculation on/in/rubbed into the anus) was associated with longer videos, more views, and group sex videos (three or more performers). The findings of high levels of sexual risk behavior and the fact that there was virtually no difference in the prevalence of anal sex with and without a condom in gay male SEM have important implications for HIV prevention efforts, future research on the role of SEM on sexual risk taking, and public health policy.

Evaluation of sexual maturity among adolescent male sickle cell ...

African Journals Online (AJOL)

Methods. We conducted a cross-sectional case-control study evaluating sexual maturation of male patients with sickle cell anaemia and those .... statistical location were calculated for continuous data and ..... Butterworth's Medical Dictionary.

Quantitative genetic models of sexual selection by male choice.

Science.gov (United States)

Nakahashi, Wataru

2008-09-01

There are many examples of male mate choice for female traits that tend to be associated with high fertility. I develop quantitative genetic models of a female trait and a male preference to show when such a male preference can evolve. I find that a disagreement between the fertility maximum and the viability maximum of the female trait is necessary for directional male preference (preference for extreme female trait values) to evolve. Moreover, when there is a shortage of available male partners or variance in male nongenetic quality, strong male preference can evolve. Furthermore, I also show that males evolve to exhibit a stronger preference for females that are more feminine (less resemblance to males) than the average female when there is a sexual dimorphism caused by fertility selection which acts only on females.

Fresh onion juice enhanced copulatory behavior in male rats with and without paroxetine-induced sexual dysfunction.

Science.gov (United States)

Allouh, Mohammed Z; Daradka, Haytham M; Al Barbarawi, Mohammed M; Mustafa, Ayman G

2014-02-01

Onion (Allium cepa) is one of the most commonly cultivated species of the family Liliaceae, and has long been used in dietary and therapeutic applications. Treatment with fresh onion juice has been reported to promote testosterone production in male rats. Testosterone is the male sex hormone responsible for enhancing sexual libido and potency. This study aimed to investigate the effects of onion juice on copulatory behavior of sexually potent male rats and in male rats with paroxetine-induced sexual dysfunction. Sexually experienced male rats were divided into seven groups: a control group, three onion juice-treated groups, a paroxetine-treated group, and two groups treated with paroxetine plus different doses of onion juice. At the end of the treatments, sexual behavior parameters and testosterone levels were measured and compared among the groups. Administration of onion juice significantly reduced mount frequency and latency and increased the copulatory efficacy of potent male rats. In addition, administration of onion juice attenuated the prolonged ejaculatory latency period induced by paroxetine and increased the percentage of ejaculating rats. Serum testosterone levels increased significantly by onion juice administration. However, a significant reduction in testosterone because of paroxetine therapy was observed. This reduction was restored to normal levels by administration of onion juice. This study conclusively demonstrates that fresh onion juice improves copulatory behavior in sexually potent male rats and in those with paroxetine-induced sexual dysfunction by increasing serum testosterone levels.

Sexual behaviour of male rats after gamma-irradiation: some radiobiological features

International Nuclear Information System (INIS)

Ushakov, I.B.; Rogacheva, I.V.; Stroganova, E.A.

1986-01-01

A pronounced and stable decrease in sexual motivation of male rats immediately after γ-irradiation of the head with a dose of 2.58 C/kg is shown. Exposure of the body to 1.29-2.58 C/kg radiation also inhibited sexual behaviour but only by the 45th-55th minute following irradiation: with higher doses some increase in sexual activity was observed immediately after irradiation

Food fight: sexual conflict over free amino acids in the nuptial gifts of male decorated crickets.

Science.gov (United States)

Gershman, S N; Hunt, J; Sakaluk, S K

2013-04-01

In decorated crickets, Gryllodes sigillatus, the spermatophore that a male transfers at mating includes a gelatinous spermatophylax that the female consumes, delaying her removal of the sperm-filled ampulla. Male fertilization success increases with the length of time females spend feeding on the spermatophylax, while females may benefit by prematurely discarding the spermatophylaxes of undesirable males. This sexual conflict should favour males that produce increasingly appealing spermatophylaxes, and females that resist this manipulation. To determine the genetic basis of female spermatophylax feeding behaviour, we fed spermatophylaxes to females of nine inbred lines and found that female genotype had a major influence on spermatophylax feeding duration. The amino acid composition of the spermatophylax was also significantly heritable. There was a positive genetic correlation between spermatophylax feeding duration and the gustatory appeal of the spermatophylax. This correlation suggests that genes expressed in males that produce more manipulative spermatophylaxes are positively linked to genes expressed in females that make them more vulnerable to manipulation. Outbred females spent less time feeding on spermatophylaxes than inbred females, and thus showed greater resistance to male manipulation. Further, in a nonspermatophylax producing cricket (Acheta domesticus), females were significantly more prone to feeding on spermatophylaxes than outbred female Gryllodes. Collectively, these results suggest a history of sexually antagonistic coevolution over the consumption of nuptial food gifts. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

Males Resemble Females: Re-Evaluating Sexual Dimorphism in Protoceratops andrewsi (Neoceratopsia, Protoceratopsidae.

Directory of Open Access Journals (Sweden)

Leonardo Maiorino

Full Text Available Protoceratops andrewsi (Neoceratopsia, Protoceratopsidae is a well-known dinosaur from the Upper Cretaceous of Mongolia. Some previous workers hypothesized sexual dimorphism in the cranial shape of this taxon, using qualitative and quantitative observations. In particular, width and height of the frill as well as the development of a nasal horn have been hypothesized as potentially sexually dimorphic.Here, we reassess potential sexual dimorphism in skulls of Protoceratops andrewsi by applying two-dimensional geometric morphometrics to 29 skulls in lateral and dorsal views. Principal Component Analyses and nonparametric MANOVAs recover no clear separation between hypothetical "males" and "females" within the overall morphospace. Males and females thus possess similar overall cranial morphologies. No differences in size between "males" and "females" are recovered using nonparametric ANOVAs.Sexual dimorphism within Protoceratops andrewsi is not strongly supported by our results, as previously proposed by several authors. Anatomical traits such as height and width of the frill, and skull size thus may not be sexually dimorphic. Based on PCA for a data set focusing on the rostrum and associated ANOVA results, nasal horn height is the only feature with potential dimorphism. As a whole, most purported dimorphic variation is probably primarily the result of ontogenetic cranial shape changes as well as intraspecific cranial variation independent of sex.

Male rats that differ in novelty exploration demonstrate distinct patterns of sexual behavior

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Cummings, Jennifer A.; Clinton, Sarah M.; Perry, Adam N.; Akil, Huda; Becker, Jill B.

2014-01-01

High versus low novelty exploration predicts a variety of behavioral differences. For example, rats selectively-bred for high novelty exploration (bred High Responders, bHR) exhibit exaggerated aggression, impulsivity, and proclivity to addictive behaviors compared to low novelty-reactive rats (bred Low Responders, bLRs), which are characterized by a high anxiety/depressive-like phenotype. Since bHR/bLR rats exhibit differences in dopaminergic circuitry and differential response to rewarding stimuli (i.e., psychostimulants, food), the present study examined whether they also differ in another key hedonic behavior – sex. Thus, adult bHR/bLR males were given five 30-min opportunities to engage in sexual activity with a receptive female. Sexual behavior and motivation were examined and compared between the groups. The bHR/bLR phenotype affected both sexual motivation and behavior, with bLR males demonstrating reduced motivation for sex compared with bHR males (i.e., fewer animals copulated, longer latency to engage in sex). The bHR males required more intromissions at a faster pace per ejaculation than did bLR males. Thus, neurobiological differences that affect motivation for drugs of abuse, aggression, and impulsivity in rats also affect sexual motivation and performance. PMID:23398441

Varieties of Male-Sexual-Identity Development in Clinical Practice:A Neuropsychoanalytic Model

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Frans eStortelder

2014-12-01

Full Text Available Variations of sexual-identity development are present in all cultures, as well as in many animal species. Freud, founding father of psychoanalysis, believed that all men have an inherited, bisexual disposition, and that many varieties of love and desire are experienced as alternative pathways to intimacy.In the neuropsychoanalytic model, psychic development starts with the constitutional self. The constitutional self is comprised of the neurobiological factors which contribute to sexual-identity development. These neurobiological factors are focused on biphasic sexual organization in the prenatal phase, based on variations in genes, sex hormones, and brain circuits. This psychosocial construction of sexual identity is determined through contingent mirroring by the parents and peers of the constitutional self. The development of the self—or personal identity—is linked with the development of sexual identity, gender-role identity, and procreative identity. Incongruent mirroring of the constitutional self causes alienation in the development of the self. Such alienation can be treated within the psychoanalytic relationship.This article presents a contemporary, neuropsychoanalytic, developmental theory of male-sexual identity relating to varieties in male-sexual-identity development, with implications for psychoanalytic treatment, and is illustrated with three vugnettes from clinical practice.

Determinants of Behavior Change Intention Among Heterosexual Thai Males Diagnosed with Sexually Transmitted Diseases.

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Thato, Ratsiri; Daengsaard, Ekkachai

2016-11-01

This study sought to identify factors associated with intention to change sexual practices among heterosexual Thai males diagnosed with sexually transmitted infections (STIs). STI clinic patients (n = 247) reported their sexual behaviors and condom use during the previous 3 months. STI and HIV knowledge, motivation to change sexual practices, and behavioral skills were assessed. Then, self-reported behavior change intention, including consistent condom use, reducing number of sexual partners, not using drugs and alcohol when having sex, and refusal of condomless sex, was examined. Consistent condom use in the past 3 months by Thai males diagnosed with STIs was low across all types of sexual partners (lover 13.8%, casual partner 14.9%, and sex worker 2.5%). Risk reduction self-efficacy (p behavior change intention. Significant predictors of behavior change intention were risk reduction self-efficacy (p behavior change intention variance. Intervention aimed at enhancing motivation and behavioral skills to adopt preventive behaviors should be developed to prevent recurrent STIs, including HIV infection, among heterosexual Thai males diagnosed with STIs.

Sexual HIV Risk Among Male Parolees and Their Female Partners: The Relate Project.

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Comfort, Megan; Reznick, Olga Grinstead; Dilworth, Samantha E; Binson, Diane; Darbes, Lynae A; Neilands, Torsten B

The massively disproportionate impact of America's prison boom on communities of color has raised questions about how incarceration may affect health disparities, including disparities in HIV. Primary partners are an important source of influence on sexual health. In this paper, we investigate sexual HIV risk among male-female couples following a man's release from prison. We draw upon data from the Relate Project, a novel cross-sectional survey of recently released men and their female partners in Oakland and San Francisco, California (N=344). Inferential analyses use the actor-partner model to explore actor and partner effects on sexual HIV risk outcomes. Dyadic analyses of sexual HIV risk among male parolees and their female partners paint a complex portrait of couples affected by incarceration and of partners' influences on each other. Findings indicate that demographic factors such as education level and employment status, individual psycho-social factors such as perception of risk, and relationship factors such as commitment and power affect sexual HIV risk outcomes. The Relate Project provides a novel dataset for the dyadic analysis of sexual risk among male parolees and their female partners, and results highlight the importance of focusing on the couple as a unit when assessing HIV risk and protective behaviors. Results also indicate potentially fruitful avenues for population-specific interventions that may help to reduce sexual health disparities among couples affected by incarceration.

Male sexual harassment alters female social behaviour towards other females.

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Darden, Safi K; Watts, Lauren

2012-04-23

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

Antihypertensive Drugs and the Sexually Active Hypertensive Male ...

African Journals Online (AJOL)

Background: Erectile dysfunction (ED) has made the initiations of therapy and continued therapy increasingly problematic in the management of the hypertensive male. There are reports suggesting beneficial effects of angiotensin II antagonists on sexual function. The effects of losartan on ED in Nigerian hypertensive men ...

Women's beliefs about male circumcision, HIV prevention, and sexual behaviors in Kisumu, Kenya.

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Thomas H Riess

Full Text Available It is important to understand how women's sexual practices may be influenced by male circumcision (MC as an HIV prevention effort. Women's beliefs about MC and sexual behaviour will likely influence the scale-up and uptake of medical MC. We conducted qualitative interviews with 30 sexually active women in Kisumu, Kenya. Women discussed MC related to perceived health benefits, condom use, sexual behaviour, knowledge of susceptibility to HIV and sexually transmitted infections (STIs, circumcision preference, and influence on circumcision uptake. Respondents had a good understanding of the partial protection of MC for acquisition of HIV for men. Women perceived circumcised men as cleaner, carrying fewer diseases, and taking more time to reach ejaculation. Male's circumcision status is a salient factor for women's sexual decision making, including partner choice, and condom use. It will be important that educational information affirms that MC provides only partial protection against female to male transmission of HIV and some STIs; that other HIV and STI prevention methods such as condoms need to be used in conjunction with MC; that MC does not preclude a man from having HIV; and that couples should develop plans for not having sex while the man is healing.

Both male and female identity influence variation in male signalling effort

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Svensson P Andreas

2011-08-01

Full Text Available Abstract Background Male sexual displays play an important role in sexual selection by affecting reproductive success. However, for such displays to be useful for female mate choice, courtship should vary more among than within individual males. In this regard, a potentially important source of within male variation is adjustment of male courtship effort in response to female traits. Accordingly, we set out to dissect sources of variation in male courtship effort in a fish, the desert goby (Chlamydogobius eremius. We did so by designing an experiment that allowed simultaneous estimation of within and between male variation in courtship, while also assessing the importance of the males and females as sources of courtship variation. Results Although males adjusted their courtship depending on the identity of the female (a potentially important source of within-male variation, among-male differences were considerably greater. In addition, male courtship effort towards a pair of females was highly repeatable over a short time frame. Conclusion Despite the plasticity in male courtship effort, courtship displays had the potential to reliably convey information about the male to mate-searching females. Our experiment therefore underscores the importance of addressing the different sources contributing to variation in the expression of sexually-selected traits.

The frequency of sexual dysfunctions in male partners of women with vaginismus in a Turkish sample.

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Dogan, S; Dogan, M

2008-01-01

The aim of this investigation is to determine the sexual history traits, sexual satisfaction level and frequency of sexual dysfunctions in men whose partners have vaginismus. The study included 32 male partners of vaginismic patients, who presented at a psychiatry department. Subjects were evaluated by a semi-structured questionnaire. The questionnaire was developed by researchers for assessing sexually dysfunctional patients and included detailed questions with regard to socio-demographic variables, general medical and sexual history. All participants also received the Golombok Rust Inventory of Sexual Satisfaction (GRISS). According to DSM-IV-TR criteria, 65.6% of the investigated males were diagnosed with one or more sexual dysfunctions. The most common problem was premature ejaculation (50%) and the second one was erectile dysfunction (28%). The transformed GRISS subscale scores provided similar data. It is concluded that the assessment of sexual functions of males who have vaginismic partners should be an integral part of the management procedure of vaginismus for optimal outcome.

Male-like sexual behavior of female mouse lacking fucose mutarotase

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Lim Dae-sik

2010-07-01

Full Text Available Abstract Background Mutarotases are recently characterized family of enzymes that are involved in the anomeric conversions of monosaccharides. The mammalian fucose mutarotase (FucM was reported in cultured cells to facilitate fucose utilization and incorporation into protein by glycosylation. However, the role of this enzyme in animal has not been elucidated. Results We generated a mutant mouse specifically lacking the fucose mutarotase (FucM gene. The FucM knockout mice displayed an abnormal sexual receptivity with a drastic reduction in lordosis score, although the animals were fertile due to a rare and forced intromission by a typical male. We examined the anteroventral periventricular nucleus (AVPv of the preoptic region in brain and found that the mutant females showed a reduction in tyrosine hydoxylase positive neurons compared to that of a normal female. Furthermore, the mutant females exhibited a masculine behavior, such as mounting to a normal female partner as well as showing a preference to female urine. We found a reduction of fucosylated serum alpha-fetoprotein (AFP in a mutant embryo relative to that of a wild-type embryo. Conclusions The observation that FucM-/- female mouse exhibits a phenotypic similarity to a wild-type male in terms of its sexual behavior appears to be due to the neurodevelopmental changes in preoptic area of mutant brain resembling a wild-type male. Since the previous studies indicate that AFP plays a role in titrating estradiol that are required to consolidate sexual preference of female mice, we speculate that the reduced level of AFP in FucM-/- mouse, presumably resulting from the reduced fucosylation, is responsible for the male-like sexual behavior observed in the FucM knock-out mouse.

Heterosexual Men's Anger in Response to Male Homosexuality: Effects of Erotic and Non-Erotic Depictions of Male-Male Intimacy and Sexual Prejudice

OpenAIRE

Hudepohl, Adam D.; Parrott, Dominic J.; Zeichner, Amos

2010-01-01

The present study compared effects of erotic and non-erotic depictions of male-male intimacy on the experience of anger in heterosexual men. Data came from three independent laboratory studies designed to elicit anger in response to erotic or non-erotic depictions of male-male and male-female intimacy. All participants completed a measure of sexual prejudice and anger was assessed before and after viewing the erotic or non-erotic video. Among high-prejudiced men, viewing erotic and non-erotic...

'Unrecognized victims': Sexual abuse against male street children in ...

African Journals Online (AJOL)

Bernt Lindtjorn

Conclusions- Sexual abuse against male children around Merkato area is rampant, but received less or no attention ..... abusers and started protecting myself from such abuse. Figure 1: .... Then I ran away fast with determination and without.

Active and passive sexual roles that arise in Drosophila male-male courtship are modulated by dopamine levels in PPL2ab neurons

OpenAIRE

Shiu-Ling Chen; Yu-Hui Chen; Chuan-Chan Wang; Yhu-Wei Yu; Yu-Chen Tsai; Hsiao-Wen Hsu; Chia-Lin Wu; Pei-Yu Wang; Lien-Cheng Chen; Tsuo-Hung Lan; Tsai-Feng Fu

2017-01-01

The neurology of male sexuality has been poorly studied owing to difficulties in studying brain circuitry in humans. Dopamine (DA) is essential for both physiological and behavioural responses, including the regulation of sexuality. Previous studies have revealed that alterations in DA synthesis in dopaminergic neurons can induce male-male courtship behaviour, while increasing DA levels in the protocerebral posteriolateral dopaminergic cluster neuron 2ab (PPL2ab) may enhance the intensity of ...

Examining the association between male circumcision and sexual function: evidence from a British probability survey.

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Homfray, Virginia; Tanton, Clare; Mitchell, Kirstin R; Miller, Robert F; Field, Nigel; Macdowall, Wendy; Wellings, Kaye; Sonnenberg, Pam; Johnson, Anne M; Mercer, Catherine H

2015-07-17

Despite biological advantages of male circumcision in reducing HIV/sexually transmitted infection acquisition, concern is often expressed that it may reduce sexual enjoyment and function. We examine the association between circumcision and sexual function among sexually active men in Britain using data from Britain's third National Survey of Sexual Attitudes and Lifestyles (Natsal-3). Natsal-3 asked about circumcision and included a validated measure of sexual function, the Natsal-SF, which takes into account not only sexual difficulties but also the relationship context and overall level of satisfaction. A stratified probability survey of 6293 men and 8869 women aged 16-74 years, resident in Britain, undertaken 2010-2012, using computer-assisted face-to-face interviewing with computer-assisted self-interview for the more sensitive questions. Logistic regression was used to calculate odds ratios (ORs) to examine the association between reporting male circumcision and aspects of sexual function among sexually active men (n = 4816). The prevalence of male circumcision in Britain was 20.7% [95% confidence interval (CI): 19.3-21.8]. There was no association between male circumcision and, being in the lowest quintile of scores for the Natsal-SF, an indicator of poorer sexual function (adjusted OR: 0.95, 95% CI: 0.76-1.18). Circumcised men were as likely as uncircumcised men to report the specific sexual difficulties asked about in Natsal-3, except that a larger proportion of circumcised men reported erectile difficulties. This association was of borderline statistical significance after adjusting for age and relationship status (adjusted OR: 1.27, 95% CI: 0.99-1.63). Data from a large, nationally representative British survey suggest that circumcision is not associated with men's overall sexual function at a population level.

Sexual affordances, perceptual-motor invariance extraction and intentional nonlinear dynamics: sexually deviant and non-deviant patterns in male subjects.

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Renaud, Patrice; Goyette, Mathieu; Chartier, Sylvain; Zhornitski, Simon; Trottier, Dominique; Rouleau, Joanne-L; Proulx, Jean; Fedoroff, Paul; Bradford, John-P; Dassylva, Benoit; Bouchard, Stephane

2010-10-01

Sexual arousal and gaze behavior dynamics are used to characterize deviant sexual interests in male subjects. Pedophile patients and non-deviant subjects are immersed with virtual characters depicting relevant sexual features. Gaze behavior dynamics as indexed from correlation dimensions (D2) appears to be fractal in nature and significantly different from colored noise (surrogate data tests and recurrence plot analyses were performed). This perceptual-motor fractal dynamics parallels sexual arousal and differs from pedophiles to non-deviant subjects when critical sexual information is processed. Results are interpreted in terms of sexual affordance, perceptual invariance extraction and intentional nonlinear dynamics.

Prosexual Effect of Chrysactinia mexicana A. Gray (Asteraceae, False Damiana, in a Model of Male Sexual Behavior

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R. Estrada-Reyes

2016-01-01

Full Text Available Chrysactinia mexicana A. Gray (Asteraceae and Turnera diffusa Willd (Turneraceae are employed in traditional medicine as aphrodisiacs; however, there is no scientific evidence supporting the prosexual properties of C. mexicana. The aim of this study was to determine whether an aqueous extract of C. mexicana (Cm stimulates rat male sexual behavior in the sexual exhaustion paradigm. Sexually exhausted (SExh male rats were treated with Cm (80, 160, and 320 mg/kg, an aqueous extract of T. diffusa (Td, or yohimbine. The sexual exhaustion state in the control group was characterized by a low percentage of males exhibiting mounts, intromissions, and ejaculations and no males demonstrating mating behavior after ejaculation. Cm (320 mg/kg, Td, or yohimbine significantly increased the proportion of SExh rats that ejaculated and resumed copulation after ejaculation. In males that exhibited reversal of sexual exhaustion, Cm (320 mg/kg improved sexual performance by reducing the number of intromissions and shrinking ejaculation latency. The effects of treatments on sexual behavior were not related with alterations in general locomotion. In conclusion, the prosexual effects of Cm, as well as those of Td, are established at a central level, which supports the traditional use of C. mexicana for stimulating sexual activity.

Prosexual Effect of Chrysactinia mexicana A. Gray (Asteraceae), False Damiana, in a Model of Male Sexual Behavior.

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Estrada-Reyes, R; Ferreyra-Cruz, O A; Jiménez-Rubio, G; Hernández-Hernández, O T; Martínez-Mota, L

Chrysactinia mexicana A. Gray (Asteraceae) and Turnera diffusa Willd (Turneraceae) are employed in traditional medicine as aphrodisiacs; however, there is no scientific evidence supporting the prosexual properties of C. mexicana . The aim of this study was to determine whether an aqueous extract of C. mexicana (Cm) stimulates rat male sexual behavior in the sexual exhaustion paradigm. Sexually exhausted (SExh) male rats were treated with Cm (80, 160, and 320 mg/kg), an aqueous extract of T. diffusa (Td), or yohimbine. The sexual exhaustion state in the control group was characterized by a low percentage of males exhibiting mounts, intromissions, and ejaculations and no males demonstrating mating behavior after ejaculation. Cm (320 mg/kg), Td, or yohimbine significantly increased the proportion of SExh rats that ejaculated and resumed copulation after ejaculation. In males that exhibited reversal of sexual exhaustion, Cm (320 mg/kg) improved sexual performance by reducing the number of intromissions and shrinking ejaculation latency. The effects of treatments on sexual behavior were not related with alterations in general locomotion. In conclusion, the prosexual effects of Cm, as well as those of Td, are established at a central level, which supports the traditional use of C. mexicana for stimulating sexual activity.

Contrasting adolescent female and male sexual aggression: a selfreport study on prevalence and predictors of sexual aggression

NARCIS (Netherlands)

Slotboom, A.; Hendriks, J.; Verbruggen, J.

2011-01-01

In this study we investigated the prevalence of sexual aggression as reported by adolescent males and females in the Netherlands. Data were collected from a low-risk school-based sample (n= 219; 119 adolescent females and 100 adolescent males), a medium-risk school-based sample (vocational training)

Vulnerable Sexuality and HIV/AIDS Prevention Knowledge among Ethnic Tribal Male Youth in Bangladesh

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Kamal, S. M. Mostafa

2012-01-01

This study examines sexuality and HIV/AIDS prevention knowledge among minority ethnic male youth of Bangladesh. A cross-sectional survey was conducted through a self-administered questionnaire on 800 young males aged 15-24 years in the Chittagong Hill Tracts region in 2009. Of the respondents, almost one-third were sexually active and of them…

Potential contribution of progesterone receptors to the development of sexual behavior in male and female mice.

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Desroziers, Elodie; Brock, Olivier; Bakker, Julie

2017-04-01

We previously showed that estradiol can have both defeminizing and feminizing effects on the developing mouse brain. Pre- and early postnatal estradiol defeminized the ability to show lordosis in adulthood, whereas prepubertal estradiol feminized this ability. Furthermore, we found that estradiol upregulates progesterone receptors (PR) during development, inducing both a male-and female-typical pattern of PR expression in the mouse hypothalamus. In the present study, we took advantage of a newly developed PR antagonist (ZK 137316) to determine whether PR contributes to either male- or female-typical sexual differentiation. Thus groups of male and female C57Bl/6j mice were treated with ZK 137316 or OIL as control: males were treated neonatally (P0-P10), during the critical period for male sexual differentiation, and females were treated prepubertally (P15-P25), during the critical period for female sexual differentiation. In adulthood, mice were tested for sexual behavior. In males, some minor effects of neonatal ZK treatment on sexual behavior were observed: latencies to the first mount, intromission and ejaculation were decreased in neonatally ZK treated males; however, this effect disappeared by the second mating test. By contrast, female mice treated with ZK during the prepubertal period showed significantly less lordosis than OIL-treated females. Mate preferences were not affected in either males or females treated with ZK during development. Taken together, these results suggest a role for PR and thus perhaps progesterone in the development of lordosis behavior in female mice. By contrast, no obvious role for PR can be discerned in the development of male sexual behavior. Copyright © 2016 Elsevier Inc. All rights reserved.

Self-grooming induced by sexual chemical signals in male root voles (Microtus oeconomus Pallas).

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Yu, Honghao; Yue, Pengpeng; Sun, Ping; Zhao, Xinquan

2010-03-01

Sniffing is one-way animals collect chemical signals, and many males self-groom when they encounter the odor of opposite-sex conspecifics. We tested the hypothesis that sexual chemical signals from females can induce self-grooming behavior in male root voles (Microtus oeconomus Pallas). Specifically, we investigated the sniffing pattern of male root voles in response to odors from the head, trunk, and tail areas of lactating and non-lactating females. The self-grooming behavior of males in response to female individual odorant stimuli was documented, and the relationship between self-grooming and sniffing of odors from the head, trunk, and tails areas were analyzed. Sniffing pattern results showed that males are most interested in odors from the head area, and more interested in odors from the tail as compared to the trunk area. Males displayed different sniffing and self-grooming behaviors when they were exposed to odors from lactating females as compared to non-lactating females. Males also spent more time sniffing and engaged in more sniffing behaviors in response to odors from the lactating females' tail area as compared to the same odors from non-lactating females. Similarly, males spent more time self-grooming and engaged in more self-grooming behaviors in the presence of individual odors from lactating females as compared to individual odors from non-lactating females. Partial correlation analyses revealed that the frequency of self-grooming was significantly correlated with the frequency of tail area sniffs. Results from this experiment suggest that sexual attractiveness of lactating females is stronger than that of non-lactating females. Furthermore, the partial correlation analysis demonstrated that self-grooming in males is induced by odors from the tail area of females. Collectively, these results support the hypothesis that sexual chemical signals from females can induce self-grooming behavior in male root voles. Self-grooming may also reflect the

Examining weight and eating behavior by sexual orientation in a sample of male veterans.

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Bankoff, Sarah M; Richards, Lauren K; Bartlett, Brooke; Wolf, Erika J; Mitchell, Karen S

2016-07-01

Eating disorders are understudied in men and in sexual minority populations; however, extant evidence suggests that gay men have higher rates of disordered eating than heterosexual men. The present study examined the associations between sexual orientation, body mass index (BMI), disordered eating behaviors, and food addiction in a sample of male veterans. Participants included 642 male veterans from the Knowledge Networks-GfK Research Panel. They were randomly selected from a larger study based on previously reported trauma exposure; 96% identified as heterosexual. Measures included the Eating Disorder Diagnostic Scale, the Yale Food Addiction Scale, and self-reported height and weight. Heterosexual and sexual minority men did not differ significantly in terms of BMI. However, gay and bisexual men (n=24) endorsed significantly greater eating disorder symptoms and food addiction compared to heterosexual men. Our findings that sexual minority male veterans may be more likely to experience eating disorder and food addiction symptoms compared to heterosexual male veterans highlight the importance of prevention, assessment, and treatment efforts targeted to this population. Published by Elsevier Inc.

Influential Factors on Adolescent Males' Non-Relational Sexual Attitudes and Behavior

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Drew, Cathy L.

2013-01-01

Adolescent males are influenced by various social and cultural factors. This qualitative study sought to further understanding about adolescent males' thoughts and behaviors regarding sexual decision-making. Specific exploration encompassed the influences of the identified factors of parents, peers, media, first romantic relationship breakups, and…

Sexual odor preference and dopamine release in the nucleus accumbens by estrous olfactory cues in sexually naïve and experienced male rats.

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Fujiwara, Masaya; Chiba, Atsuhiko

2018-03-01

Sexual behavior is a natural reward that activates mesolimbic dopaminergic system. Microdialysis studies have shown that extracellular level of dopamine (DA) in the nucleus accumbens (NAcc) significantly increases during copulation in male rats. The NAcc DA level is also known to be increased during the presentation of a sexually receptive female before mating. This rise in DA was probably associated with sexual motivation elicited by incentive stimuli from the receptive female. These microdialysis studies, however, did not thoroughly investigated if olfactory stimuli from estrous females could significantly increase the extracellular DA in the NAcc of male rats. The present study was designed to examine systematically the relationship between the expression of preference for the olfactory stimuli from estrous females and the effects of these stimuli on the extracellular DA levels in the NAcc measured by in vivo microdialysis in male Long-Evans (LE) rats. We used two types of olfactory stimuli, either airborne odors (volatile stimuli) or soiled bedding (volatile plus nonvolatile stimuli). The sexually experienced male rats, which experienced six ejaculations, significantly preferred both of these olfactory stimuli from estrous females as opposed to males. Exposure to these female olfactory stimuli gradually increased extracellular DA in the NAcc, which reached significantly higher level above baseline during the period following the removal of the stimuli although not during the 15-min stimulus presentation period. The sexually naïve male rats, on the other hand, showed neither preference for olfactory stimuli from estrous females nor increase in the NAcc DA after exposure to these stimuli. These data suggest that in male LE rats olfactory stimuli from estrous females in and of themselves can be conditional cues that induce both incentive motivation and a significant increase in the NAcc DA probably as a result of being associated with sexual reward through

Exposure to harsh parenting and pornography as explanations for males' sexual coercion and females' sexual victimization.

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Simons, Leslie Gordon; Simons, Ronald L; Lei, Man-Kit; Sutton, Tara E

2012-01-01

Sexual violence against women is a major concern to researchers and policy makers, as well as to the general public. This study uses a sample of more than 2,000 college students to investigate the extent to which exposure to harsh parenting practices and sexually explicit materials contributes to perpetration and victimization. Findings indicate that frequent corporal punishment in the family of origin combined with consumption of pornographic materials increased the probability that males reported engaging in coercive sexual practices. For females, both frequent corporal punishment and exposure to paternal hostility combined with consumption of pornographic materials were associated with higher levels of reported sexual victimization. These results provide increased understanding of the impact of pornography use among a nonclinical sample, as well as the consequences of experiencing harsh corporal punishment in one's family of origin, on the sexual victimization of females.

Female burying beetles benefit from male desertion: sexual conflict and counter-adaptation over parental investment.

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Giuseppe Boncoraglio

Full Text Available Sexual conflict drives the coevolution of sexually antagonistic traits, such that an adaptation in one sex selects an opposing coevolutionary response from the other. Although many adaptations and counteradaptations have been identified in sexual conflict over mating interactions, few are known for sexual conflict over parental investment. Here we investigate a possible coevolutionary sequence triggered by mate desertion in the burying beetle Nicrophorus vespilloides, where males commonly leave before their offspring reach independence. Rather than suffer fitness costs as a consequence, our data suggest that females rely on the male's absence to recoup some of the costs of larval care, presumably because they are then free to feed themselves on the carcass employed for breeding. Consequently, forcing males to stay until the larvae disperse reduces components of female fitness to a greater extent than caring for young singlehandedly. Therefore we suggest that females may have co-evolved to anticipate desertion by their partners so that they now benefit from the male's absence.

Female Burying Beetles Benefit from Male Desertion: Sexual Conflict and Counter-Adaptation over Parental Investment

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Boncoraglio, Giuseppe; Kilner, Rebecca M.

2012-01-01

Sexual conflict drives the coevolution of sexually antagonistic traits, such that an adaptation in one sex selects an opposing coevolutionary response from the other. Although many adaptations and counteradaptations have been identified in sexual conflict over mating interactions, few are known for sexual conflict over parental investment. Here we investigate a possible coevolutionary sequence triggered by mate desertion in the burying beetle Nicrophorus vespilloides, where males commonly leave before their offspring reach independence. Rather than suffer fitness costs as a consequence, our data suggest that females rely on the male's absence to recoup some of the costs of larval care, presumably because they are then free to feed themselves on the carcass employed for breeding. Consequently, forcing males to stay until the larvae disperse reduces components of female fitness to a greater extent than caring for young singlehandedly. Therefore we suggest that females may have co-evolved to anticipate desertion by their partners so that they now benefit from the male's absence. PMID:22355390

Sexual Behavior in Male Adolescents with Autism and Its Relation to Social-Sexual Skills in the Kingdom of Saudi Arabia

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Huwaidi, Mohamed A.; Daghustani, Wid H.

2013-01-01

The present study aimed to identify common sexual behavior among adolescents with autism, where parents and teachers of sixty-one male adolescents from twelve to twenty-one years of age were recruited from three cities in the Kingdom of Saudi Arabia. They were asked to respond to a sexual behavior questionnaire, and a social-sexual skills…

Standards for Clinical Trials in Male and Female Sexual Dysfunction: II. Patient-Reported Outcome Measures.

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Fisher, William A; Gruenwald, Ilan; Jannini, Emmanuele A; Lev-Sagie, Ahinoam; Lowenstein, Lior; Pyke, Robert E; Reisman, Yakov; Revicki, Dennis A; Rubio-Aurioles, Eusebio

2016-12-01

The second article in this series, Standards for Clinical Trials in Male and Female Sexual Dysfunction, focuses on measurement of patient-reported outcomes (PROs). Together with the design of appropriate phase I to phase IV clinical trials, the development, validation, choice, and implementation of valid PRO measurements-the focus of the present article-form the foundation of research on treatments for male and female sexual dysfunctions. PRO measurements are assessments of any aspect of a patient's health status that come directly from the patient (ie, without the interpretation of the patient's responses by a physician or anyone else). PROs are essential for assessing male and female sexual dysfunction and treatment response, including symptom frequency and severity, personal distress, satisfaction, and other measurements of sexual and general health-related quality of life. Although there are some relatively objective measurements of sexual dysfunction (ie, intravaginal ejaculatory latency time, frequency of sexual activity, etc), these measurements do not comprehensively assess the occurrence and extent of sexual dysfunction or treatment on the patient's symptoms, functioning, and well-being. Data generated by a PRO instrument can provide evidence of a treatment benefit from the patient's perspective. Copyright © 2016 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

Military Personnel: Actions Needed to Address Sexual Assaults of Male Servicemembers

Science.gov (United States)

2015-03-01

providers we interviewed said that these same traditional gender stereotypes can make it particularly difficult for males to report that they were...develop a plan for using its data to inform program development; systematically evaluate whether male victims have gender - specific medical and...not systematically identified whether male victims have any gender -specific needs. DOD sexual assault policies specify that care be sensitive to gender

Effects of male sex hormones on gender identity, sexual behavior, and cognitive function.

Science.gov (United States)

Zhu, Yuan-shan; Cai, Li-qun

2006-04-01

Androgens, the male sex hormones, play an essential role in male sexual differentiation and development. However, the influence of these sex hormones extends beyond their roles in sexual differentiation and development. In many animal species, sex hormones have been shown to be essential for sexual differentiation of the brain during development and for maintaining sexually dimorphic behavior throughout life. The principals of sex determination in humans have been demonstrated to be similar to other mammals. However, the hormonal influence on sexual dimorphic differences in the nervous system in humans, sex differences in behaviors, and its correlations with those of other mammals is still an emerging field. In this review, the roles of androgens in gender and cognitive function are discussed with the emphasis on subjects with androgen action defects including complete androgen insensitivity due to androgen receptor mutations and 5alpha-reductase-2 deficiency syndromes due to 5alpha-reductase-2 gene mutations. The issue of the complex interaction of nature versus nurture is addressed.

Interactions between aromatase (estrogen synthase) and dopamine in the control of male sexual behavior in quail.

Science.gov (United States)

Balthazart, Jacques; Baillien, Michelle; Ball, Gregory F

2002-05-01

In male quail, like in other vertebrates including rodents, testosterone acting especially through its estrogenic metabolites is necessary for the activation of male sexual behavior. Also, the administration of dopamine agonists and antagonists profoundly influences male sexual behavior. How the steroid-sensitive neural network and dopamine interact physiologically, remains largely unknown. It is often implicitly assumed that testosterone or its metabolite estradiol, stimulates male sexual behavior via the modification of dopaminergic transmission. We have now identified in quail two possible ways in which dopamine could potentially affect sexual behavior by modulating the aromatization of testosterone into an estrogen. One is a long-acting mechanism that presumably involves the modification of dopaminergic transmission followed by the alteration of the genomic expression of aromatase. The other is a more rapid mechanism that does not appear to be dopamine receptor-mediated and may involve a direct interaction of dopamine with aromatase (possibly via substrate competition). We review here the experimental data supporting the existence of these controls of aromatase activity by dopamine and discuss the possible contribution of these controls to the activation of male sexual behavior.

Anxious and Hostile: Consequences of Anxious Adult Attachment in Predicting Male-Perpetrated Sexual Assault.

Science.gov (United States)

Barbaro, Nicole; Parkhill, Michele R; Nguyen, David

2018-07-01

Attachment theory has increasingly been utilized to understand the etiology of sexual violence, and anxious attachment appears to be especially informative in this domain. We investigate the influence of general anxious attachment and specific anxious attachment on hostile masculine attitudes to predict male-perpetrated sexual assault. We hypothesize that hostile masculinity will mediate the relationship between general anxious attachment style and sexual assault perpetration (Hypothesis 1) and the relationship between specific anxious attachment to the assaulted woman and sexual assault perpetration (Hypothesis 2). Men ( N = 193) completed the Sexual Experiences Survey (SES) to determine sexual assault history and completed measures of general attachment style, specific attachment to the woman involved in the sexual activity, and measures of hostile masculine attitudes. Results support the hypothesized mediation models, such that general anxious attachment and specific anxious attachment are significantly associated with hostile masculinity, which in turn, predicts the likelihood of male-perpetrated sexual assault. The findings suggest that the unique characteristics of anxious attachment may escalate into hostile masculinity, which then increases the likelihood of sexual assault perpetration. This research is the first to investigate attachment bonds to the woman involved in the sexual activity and likelihood of sexual assault perpetration against the same woman.

The association between the fraternal birth order effect in male homosexuality and other markers of human sexual orientation

OpenAIRE

Rahman, Qazi

2005-01-01

Later fraternal birth order (FBO) is a well-established correlate of homosexuality in human males and may implicate a maternal immunization response in the feminization of male sexuality. This has led to the suggestion that FBO may relate to other markers of male sexual orientation which are robustly sexually dimorphic. If so, among homosexual males the number of older brothers should strongly correlate with traits such as spatial ability and psychological gender, indicative of greater behavi...

The roles of testicular nuclear receptor 4 (TR4 in male fertility-priapism and sexual behavior defects in TR4 knockout mice

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Bao Bo-Ying

2011-10-01

Full Text Available Abstract Background Successful reproductive efforts require the establishment of a situation favorable for reproduction that requires integration of both behavior and internal physiological events. TR4 nuclear receptor is known to be involved in male fertility via controlling spermatogenesis, yet its roles in regulating other biological events related to reproduction have not been completely revealed. Methods Male TR4 knockout (TR4-/- and wild type mice were used for the sexual behavior and penile dysfunction studies. Mice were sacrificed for histological examination and corresponding genes profiles were analyzed by quantitative RT-PCR. Reporter gene assays were performed. Results We describe an unexpected finding of priapism in TR4-/- mice. As a transcriptional factor, we demonstrated that TR4 transcriptionally modulates a key enzyme regulating penis erection and neuronal nitric oxide synthese NOS (nNOS. Thereby, elimination of TR4 results in nNOS reduction in both mRNA and protein levels, consequently may lead to erectile dysfunction. In addition, male TR4-/- mice display defects in sexual and social behavior, with increased fear or anxiety, as well as reduced mounting, intromission, and ejaculation. Reduction of ER alpha, ER beta, and oxytocin in the hypothalamus may contribute to defects in sexual behavior and stress response. Conclusions Together, these results provide in vivo evidence of important TR4 roles in penile physiology, as well as in male sexual behavior. In conjunction with previous finding, TR4 represents a key factor that controls male fertility via regulating behavior and internal physiological events.

Sexual function in male patients with obstructive sleep apnoea after 1 year of CPAP treatment

DEFF Research Database (Denmark)

Petersen, Marian Christin; Kristensen, Ellids; Berg, Søren

2012-01-01

OBJECTIVE: Our objective was to investigate what impact 1 year of effective nocturnal continuous positive airway pressure (CPAP) treatment had on general and functional aspects of sexuality in male patients with a confirmed diagnosis of obstructive sleep apnoea (OSA). METHODS: Before and after 1...... year of CPAP treatment, a total of 207 CPAP-compliant male patients (age 26-77) received a survey with questions drawn from two self-administered questionnaires on sexuality - Life Satisfaction 11 (LiSat-11) and brief sexual function inventory (BSFI). For assessment of daytime sleepiness, we used...... of CPAP treatment. ESS score decreased significantly after 1 year of CPAP treatment. CONCLUSION: One year of CPAP treatment improves all aspects of sexual function in male patients with OSA. Our data indirectly suggest that organic factors are the most likely explanation to these improvements....

Let’s Talk About Sex: Parental Communication and Sexual Behavior of Male Filipino Youth

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Goldilyn D. Gumban

2016-05-01

Full Text Available Understanding the sexual behavior of young people is important in pursuing health development in our society. In the Philippines, current data shows that there is a drastic increase in sex related activities concerning our youths. According to past studies, strong familial relationship and parent-child connectedness decrease the likelihood of a child to engage in risky sex. Furthermore, families with strong communication and are open to sexual topics became closer, and more comfortable with each other. This quantitative, correlational study was designed to describe the level of parental communication in terms of sexual health issues and its relationship to the sexual behaviorsof male Filipino youths in Metro Manila. A total of 143 male respondents ages 18-25 from Metro Manila participated in the study through an online survey. Results suggest that that majority of the respondents reported low level of parental communication in terms of sexual health issues and a large number reported risky sexual behaviors. The results of this study suggested no significant relationship between the respondent‟s level of parental communication and their sexual behavior.

CE: Military Sexual Trauma in Male Service Members.

Science.gov (United States)

Eckerlin, Denise M; Kovalesky, Andrea; Jakupcak, Matthew

2016-09-01

: The experience of military sexual trauma (MST), which can result from assault, battery, or harassment of a sexual nature, may jeopardize the mental health of service members as well as that of their family members, colleagues, and community members. Although a greater proportion of female than male service members are subjected to MST, the Department of Defense estimates that the absolute numbers of affected men and women, across all ranks and branches of military service, are nearly equal because roughly 85% of military members are men. Little research has explored the effects of MST on men. This article discusses the unique ways in which men may experience MST, and examines how social stereotypes of masculinity, myths surrounding sexual assault, and military culture and structure often influence a man's interpretation of an attack and his likelihood of reporting the incident or seeking treatment. It describes current treatments for MST-related mental health conditions and addresses implications for nurses and other health care professionals.

The relative nature of fertilization success: Implications for the study of post-copulatory sexual selection

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García-González Francisco

2008-05-01

Full Text Available Abstract Background The determination of genetic variation in sperm competitive ability is fundamental to distinguish between post-copulatory sexual selection models based on good-genes vs compatible genes. The sexy-sperm and the good-sperm hypotheses for the evolution of polyandry require additive (intrinsic effects of genes influencing sperm competitiveness, whereas the genetic incompatibility hypothesis invokes non-additive genetic effects. A male's sperm competitive ability is typically estimated from his fertilization success, a measure that is dependent on the ability of rival sperm competitors to fertilize the ova. It is well known that fertilization success may be conditional to genotypic interactions among males as well as between males and females. However, the consequences of effects arising from the random sampling of sperm competitors upon the estimation of genetic variance in sperm competitiveness have been overlooked. Here I perform simulations of mating trials performed in the context of sibling analysis to investigate whether the ability to detect additive genetic variance underlying the sperm competitiveness phenotype is hindered by the relative nature of fertilization success measurements. Results Fertilization success values render biased sperm competitive ability values. Furthermore, asymmetries among males in the errors committed when estimating sperm competitive abilities are likely to exist as long as males exhibit variation in sperm competitiveness. Critically, random effects arising from the relative nature of fertilization success lead to an underestimation of underlying additive genetic variance in sperm competitive ability. Conclusion The results show that, regardless of the existence of genotypic interactions affecting the output of sperm competition, fertilization success is not a perfect predictor of sperm competitive ability because of the stochasticity of the background used to obtain fertilization success

Changes in androgen receptor, estrogen receptor alpha, and sexual behavior with aging and testosterone in male rats.

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Wu, Di; Gore, Andrea C

2010-07-01

Reproductive aging in males is characterized by a diminution in sexual behavior beginning in middle age. We investigated the relationships among testosterone, androgen receptor (AR) and estrogen receptor alpha (ERalpha) cell numbers in the hypothalamus, and their relationship to sexual performance in male rats. Young (3months) and middle-aged (12months) rats were given sexual behavior tests, then castrated and implanted with vehicle or testosterone capsules. Rats were tested again for sexual behavior. Numbers of AR and ERalpha immunoreactive cells were counted in the anteroventral periventricular nucleus and the medial preoptic nucleus, and serum hormones were measured. Middle-aged intact rats had significant impairments of all sexual behavior measures compared to young males. After castration and testosterone implantation, sexual behaviors in middle-aged males were largely comparable to those in the young males. In the hypothalamus, AR cell density was significantly (5-fold) higher, and ERalpha cell density significantly (6-fold) lower, in testosterone- than vehicle-treated males, with no age differences. Thus, restoration of serum testosterone to comparable levels in young and middle-aged rats resulted in similar preoptic AR and ERalpha cell density concomitant with a reinstatement of most behaviors. These data suggest that age-related differences in sexual behavior cannot be due to absolute levels of testosterone, and further, the middle-aged brain retains the capacity to respond to exogenous testosterone with changes in hypothalamic AR and ERalpha expression. Our finding that testosterone replacement in aging males has profound effects on hypothalamic receptors and behavior has potential medical implications for the treatment of age-related hypogonadism in men. Copyright 2010 Elsevier Inc. All rights reserved.

Structural Intervention With School Nurses Increases Receipt of Sexual Health Care Among Male High School Students.

Science.gov (United States)

Dittus, Patricia J; Harper, Christopher R; Becasen, Jeffrey S; Donatello, Robin A; Ethier, Kathleen A

2018-01-01

Adolescent males are less likely to receive health care and have lower levels of sexual and reproductive health (SRH) knowledge than adolescent females. The purpose of this study was to determine if a school-based structural intervention focused on school nurses increases receipt of condoms and SRH information among male students. Interventions to improve student access to sexual and reproductive health care were implemented in six urban high schools with a matched set of comparison schools. Interventions included working with school nurses to improve access to sexual and reproductive health care, including the provision of condoms and information about pregnancy and sexually transmitted disease prevention and services. Intervention effects were assessed through five cross-sectional yearly surveys, and analyses include data from 13,740 male students. Nurses in intervention schools changed their interactions with male students who visited them for services, such that, among those who reported they went to the school nurse for any reason in the previous year, those in intervention schools reported significant increases in receipt of sexual health services over the course of the study compared with students in comparison schools. Further, these results translated into population-level effects. Among all male students surveyed, those in intervention schools were more likely than those in comparison schools to report increases in receipt of sexual health services from school nurses. With a minimal investment of resources, school nurses can become important sources of SRH information and condoms for male high school students. Published by Elsevier Inc.

Correlates of sexual faithfulness among low-literate rural males in ...

African Journals Online (AJOL)

efficacy and social norms pertaining to faithfulness, sexual abstinence and condom use are needed to halt the spread of HIV among low-literate males in rural Amhara. Keywords: attitudes, behaviour, East Africa, HIV prevention, men, ...

Mortality of tyrophagus putrescentiae (Schrank) females exposed to a high ratio of gamma-irradiated males as an index of radiation impact on sexual vigor of males

International Nuclear Information System (INIS)

Ignatowicz, S.

1990-01-01

A 40 or 60 krad dose of gamma radiation reduce slightly sexual activity of the males but male activity is greatly reduced as the radiation dose increases from 60 to 120 krad. Females of the mold mite, Tyrophagus, putrescentiae (Schrank), molested by males present at a 3:1 or 5:1 ratio live shorter than females kept with one male. The SAG test can be applied to compare sexual activity of males treated with different dosage of gamma irradiation

Sexually selected females in the monogamous Western Australian seahorse.

Science.gov (United States)

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

2007-02-22

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

Male sexual function and lower urinary tract symptoms after laparoscopic total mesorectal excision

NARCIS (Netherlands)

Breukink, S. O.; Driel, M. F. van; Pierie, J. P. E. N.; Dobbins, C.; Wiggers, T.; Meijerink, W. J. H. J.

2008-01-01

The aim of this study was to investigate sexual function and the presence of lower urinary tract symptoms (LUTS) in male patients with rectal cancer following short-term radiotherapy and laparoscopic total mesorectal excision (LTME) by physical and psychological measurements. Sexual function and

Sigmund Freud and his impact on our understanding of male sexual dysfunction.

Science.gov (United States)

Hartmann, Uwe

2009-08-01

Sigmund Freud was one of the most influential thinkers and theorists of the 20th century. His groundbreaking work laid the foundation to many concepts and theories relevant to modern sexual medicine. To evaluate Freud's approaches to the understanding of male sexual dysfunction both in their historical context and with respect to their significance for contemporary research and therapy of sexual problems. After a brief biographical sketch, two of Freud's writings, the widely acclaimed "Three Essays on the Theory of Sexuality" from 1905, and a short article entitled "The Most Prevalent Form of Degradation in Erotic Life" from 1912, were analyzed, especially for their relevance to present treatment concepts of male sexual dysfunction. In Freud's clinical practice "psychical impotence" was a highly prevalent complaint. In his view, this dysfunction was caused by an inhibition due to an unresolved neurotic fixation leading to an arrest of the libidinal development. The result is a splitting of the tender and the sensual dimension of sexuality, most notably in the so-called madonna-whore complex. The degree of this dissociation (total or partial) determines the severity of the ensuing sexual dysfunction. In Freud's rather pessimistic view, the erotic life of civilized people tends to be characterized by some degree of this condition. While some of Freud's theories are obsolete today, many parts of his work appear to be astonishingly modern, even in the light of current neurobiological research and recent models of sexual dysfunction. Above all, Freud was an extremely gifted observer of human behavior who shows us that in many cases, sexual dysfunctions are no isolated phenomena, but have their roots in biographically based intrapsychic or interpersonal conflicts.

Factors that Influence Male Involvement in Sexual and Reproductive ...

African Journals Online (AJOL)

Erah

discuss matters of sexuality with his female children. This cultural belief not only protects men from discussing issues of reproductive health; it contributes to the general lack of male involvement in reproductive health. Although the majority of participants mentioned that most married men. (especially the older generation) ...

Effects of exposure to a mobile phone on sexual behavior in adult male rabbit: an observational study.

Science.gov (United States)

Salama, N; Kishimoto, T; Kanayama, H-o; Kagawa, S

2010-01-01

The accumulating effects of exposure to electromagnetic radiation emitted by a conventional mobile phone (MP) on male sexual behaviour have not yet been analyzed. Therefore, we studied these effects in 18 male rabbits that were randomly divided into phone and control groups. Six female teasers were taken successively to the male's cage and the copulatory behavior was recorded. Serum total testosterone, dopamine and cortisol were evaluated. The animals of the phone group were exposed to MPs (800 MHz) in a standby position for 8 h daily for 12 weeks. At the end of the study, the copulatory behavior and hormonal assays were re-evaluated. Mounts without ejaculation were the main mounts in the phone group and its duration and frequency increased significantly compared with the controls, whereas the reverse was observed in its mounts with ejaculation. Ejaculation frequency dropped significantly, biting/grasping against teasers increased notably and mounting latency in accumulated means from the first to the fourth teasers were noted in the phone group. The hormonal assays did not show any significant differences between the study groups. Therefore, the pulsed radiofrequency emitted by a conventional MP, which was kept on a standby position, could affect the sexual behavior in the rabbit.

Prevalence and correlates of sexual risk among male and female sex workers in Tijuana, Mexico.

Science.gov (United States)

Katsulis, Yasmina; Durfee, Alesha

2012-01-01

We investigated prevalence and correlates of sexual risk behaviours among male and female sex workers in Tijuana, Mexico, the busiest border crossing area on the US - Mexico border, analysing survey data from a purposive, cross-sectional sample of male and female sex workers who worked in a range of indoor and outdoor settings. Logistic regression was used to determine factors that were associated with sexual risk-taking, defined as failing to use a condom with last client. In bivariate regression models, gender, work setting (e.g., indoor vs. outdoor), poverty, engaging in survival sex, marital status and perceived drug addiction were correlated with sexual risk. When controlling for work location, housing insecurity, poverty, survival sex, marital status and perceived drug addiction, male sex workers were still 10 times more likely than female sex workers (FSW) to engage in sex without a condom during their last encounter with a client. And, although FSW were significantly more likely than males to have used a condom with a client, they were significantly less likely than males to have used a condom with their regular partner. Future research should further examine how gender shapes sexual risk activities in both commercial and non-commercial relationships.

Testosterone, plumage colouration and extra-pair paternity in male North-American barn swallows.

Directory of Open Access Journals (Sweden)

Cas Eikenaar

Full Text Available In most monogamous bird species, circulating testosterone concentration in males is elevated around the social female's fertile period. Variation in elevated testosterone concentrations among males may have a considerable impact on fitness. For example, testosterone implants enhance behaviours important for social and extra-pair mate choice. However, little is known about the relationship between natural male testosterone concentration and sexual selection. To investigate this relationship we measured testosterone concentration and sexual signals (ventral plumage colour and tail length, and determined within and extra-pair fertilization success in male North American barn swallows (Hirundo rustica erythrogaster. Dark rusty coloured males had higher testosterone concentrations than drab males. Extra-pair paternity was common (42% and 31% of young in 2009 and 2010, respectively, but neither within- nor extra-pair fertilization success was related to male testosterone concentration. Dark rusty males were less often cuckolded, but did not have higher extra-pair or total fertilization success than drab males. Tail length did not affect within- or extra-pair fertilization success. Our findings suggest that, in North American barn swallows, male testosterone concentration does not play a significant direct role in female mate choice and sexual selection. Possibly plumage colour co-varies with a male behavioural trait, such as aggressiveness, that reduces the chance of cuckoldry. This could also explain why dark males have higher testosterone concentrations than drab males.

Greater sexual risk-taking in female and male recreational MDMA/ecstasy users compared with alcohol drinkers: a questionnaire study.

Science.gov (United States)

May, Aimee L; Parrott, Andrew C

2015-07-01

Previous studies have shown increased sexual risk-taking in experienced MDMA/ecstasy users. The main objectives of this study were to compare levels of sexual risk-taking between a young student sample of predominantly heterosexual MDMA users and alcohol-drinker controls and investigate potential gender differences. Recreational drug use and sexual risk questionnaires were completed by 20 MDMA users (10 females, 10 males) and 20 non-user controls (10 females, 10 males). They were predominantly university students, aged between 20-22 years, mainly heterosexual (n = 37), with three bisexual participants. MDMA users displayed significantly greater levels of sexual risk-taking than the alcohol-drinker controls. It involved significantly higher rates of casual sex, non-condom use during sex, and penetrative sexual risks. This increase in sexual riskiness occurred to a similar extent in males and females. These findings indicate that both female and male ecstasy/MDMA users reported more risky sexual behaviours, than the non-user controls. Further research into the sexual behaviour and sexual risk-taking of heterosexual MDMA users should be conducted because much of the past literature has focused on homosexual participants. Copyright © 2015 John Wiley & Sons, Ltd.

A study of the prostate, androgens and sexual activity of male rats

Directory of Open Access Journals (Sweden)

Garcia Luis I

2007-03-01

Full Text Available Abstract Background The prostate is a sexual gland that produces important substances for the potency of sperm to fertilize eggs within the female reproductive tract, and is under complex endocrine control. Taking advantage of the peculiar behavioral pattern of copulating male rats, we developed experimental paradigms to determine the influence of sexual behavior on the level of serum testosterone, prostate androgen receptors, and mRNA for androgen receptors in male rats displaying up to four consecutive ejaculations. Methods The effect of four consecutive ejaculations was investigated by determining levels of (i testosterone in serum by solid phase RIA, (ii androgen receptors at the ventral prostate with Western Blots, and (iii androgen receptors-mRNA with RT-PCR. Data were analyzed with a one-way ANOVA followed by a post hoc application of Dunnett's test if required. Results The constant execution of sexual behavior did not produce any change in the weight of the ventral prostate. Serum testosterone increased after the second ejaculation, and remained elevated even after four ejaculations. The androgen receptor at the ventral prostate was higher after the first to third ejaculations, but returned suddenly to baseline levels after the fourth ejaculation. The level of mRNA increased after the first ejaculation, continued to increase after the second, and reached the highest peak after the third ejaculation; however, it returned suddenly to baseline levels after the fourth ejaculation. Conclusion Four consecutive ejaculations by sexually experienced male rats had important effects on the physiological responses of the ventral prostate. Fast responses were induced as a result of sexual behavior that involved an increase and decrease in androgen receptors after one and four ejaculations, respectively. However, a progressive response was observed in the elevation of mRNA for androgen receptors, which also showed a fast decrease after four

Precipitated withdrawal counters the adverse effects of subchronic cannabinoid administration on male rat sexual behavior.

Science.gov (United States)

Riebe, Caitlin J; Lee, Tiffany T; Hill, Matthew N; Gorzalka, Boris B

2010-03-26

In the present study, sexual behavior of male rats was assessed following prolonged treatment with the CB(1) receptor agonist, HU-210 (0.1mg/mg/day for 10 days) under conditions of drug maintenance, spontaneous withdrawal and precipitated withdrawal (induced via administration of the CB(1) receptor antagonist AM251; 1mg/kg). Following subchronic cannabinoid treatment, sexual activity in male rats was impaired under both the drug maintenance and spontaneous withdrawal conditions, as revealed by a reduction in frequency of both intromissions and ejaculations. Notably, the induction of precipitated drug withdrawal reversed the negative effects of subchronic HU-210 treatment on sexual activity as seen by a reversal of the suppression of ejaculations. These data illustrate that, contrary to expectations, the impairments in male sexual activity following protracted cannabinoid administration are not due to drug withdrawal, per se, but are likely mediated by neuroadaptive changes provoked by repeated drug exposure. 2010 Elsevier Ireland Ltd. All rights reserved.

Interspecies sexual behaviour between a male Japanese macaque and female sika deer.

Science.gov (United States)

Pelé, Marie; Bonnefoy, Alexandre; Shimada, Masaki; Sueur, Cédric

2017-04-01

Interspecies sexual behaviour or 'reproductive interference' has been reported across a wide range of animal taxa. However, most of these occurrences were observed in phylogenetically close species and were mainly discussed in terms of their effect on fitness, hybridization and species survival. The few cases of heterospecific mating in distant species occurred between animals that were bred and maintained in captivity. Only one scientific study has reported this phenomenon, describing sexual harassment of king penguins by an Antarctic fur seal. This is the first article to report mating behaviour between a male Japanese macaque (Macaca fuscata yakui) and female sika deer (Cervus nippon yakushimae) on Yakushima Island, Japan. Although Japanese macaques are known to ride deer, this individual showed clearly sexual behaviour towards several female deer, some of which tried to escape whilst others accepted the mount. This male seems to belong to a group of peripheral males. Although this phenomenon may be explained as copulation learning, this is highly unlikely. The most realistic hypothesis would be that of mate deprivation, which states that males with limited access to females are more likely to display this behaviour. Whatever the cause for this event may be, the observation of highly unusual animal behaviour may be a key to understanding the evolution of heterospecific mating behaviour in the animal kingdom.

Sexual orientation related differences in cortical thickness in male individuals.

Directory of Open Access Journals (Sweden)

Christoph Abé

Full Text Available Previous neuroimaging studies demonstrated sex and also sexual orientation related structural and functional differences in the human brain. Genetic information and effects of sex hormones are assumed to contribute to the male/female differentiation of the brain, and similar effects could play a role in processes influencing human's sexual orientation. However, questions about the origin and development of a person's sexual orientation remain unanswered, and research on sexual orientation related neurobiological characteristics is still very limited. To contribute to a better understanding of the neurobiology of sexual orientation, we used magnetic resonance imaging (MRI in order to compare regional cortical thickness (Cth and subcortical volumes of homosexual men (hoM, heterosexual men (heM and heterosexual women (heW. hoM (and heW had thinner cortices primarily in visual areas and smaller thalamus volumes than heM, in which hoM and heW did not differ. Our results support previous studies, which suggest cerebral differences between hoM and heM in regions, where sex differences have been reported, which are frequently proposed to underlie biological mechanisms. Thus, our results contribute to a better understanding of the neurobiology of sexual orientation.

Sexual orientation related differences in cortical thickness in male individuals.

Science.gov (United States)

Abé, Christoph; Johansson, Emilia; Allzén, Elin; Savic, Ivanka

2014-01-01

Previous neuroimaging studies demonstrated sex and also sexual orientation related structural and functional differences in the human brain. Genetic information and effects of sex hormones are assumed to contribute to the male/female differentiation of the brain, and similar effects could play a role in processes influencing human's sexual orientation. However, questions about the origin and development of a person's sexual orientation remain unanswered, and research on sexual orientation related neurobiological characteristics is still very limited. To contribute to a better understanding of the neurobiology of sexual orientation, we used magnetic resonance imaging (MRI) in order to compare regional cortical thickness (Cth) and subcortical volumes of homosexual men (hoM), heterosexual men (heM) and heterosexual women (heW). hoM (and heW) had thinner cortices primarily in visual areas and smaller thalamus volumes than heM, in which hoM and heW did not differ. Our results support previous studies, which suggest cerebral differences between hoM and heM in regions, where sex differences have been reported, which are frequently proposed to underlie biological mechanisms. Thus, our results contribute to a better understanding of the neurobiology of sexual orientation.

Monoamine levels in the nucleus accumbens correlate with male sexual behavior in middle-aged rats.

Science.gov (United States)

Tsai, Houng-Wei; Shui, Hao-Ai; Liu, Hang-Shen; Tai, Mei-Yun; Tsai, Yuan-Feen

2006-02-01

The correlation between monoamine levels in the nucleus accumbens (NAcc) and male sexual behavior was studied in middle-aged rats. Male rats (18-19months) were assigned to three groups: (1) Group MIE consisted of rats showing mounts, intromissions, and ejaculations; (2) Group MI was composed of rats showing mounts and intromissions, but no ejaculation; and (3) Group NC were non-copulators showing no sexual behavior. Young adult rats (4-5months), displaying complete copulatory behavior, were used as the control group. Levels of dopamine (DA), serotonin, and norepinephrine and their metabolites in the NAcc were measured by high-pressure liquid chromatography with electrochemical detection. No difference was seen in DA levels between MIE rats and young controls, whereas DA levels in NC rats were significantly lower than those in both MIE and MI rats. Serotonin levels in NC rats were significantly higher than those in MIE and MI rats. Conversely, norepinephrine levels in NC rats were lower than those in MIE rats. These results suggest that monoamine levels in the NAcc correlate with sexual performance in male rats and that changes in NAcc monoamine levels might affect male sexual behavior in middle-aged rats.

Teen dating violence perpetration and relation to STI and sexual risk behaviours among adolescent males.

Science.gov (United States)

Reed, Elizabeth; Miller, Elizabeth; Raj, Anita; Decker, Michele R; Silverman, Jay G

2014-06-01

To investigate teen dating violence (TDV) perpetration (physical, sexual or psychological violence) and association with STI and related sexual risk behaviours among urban male adolescents. Adolescent male survey participants (N=134) were aged 14-20 years, recruited from urban health centres. Using crude and adjusted logistic regression, TDV perpetration was examined in relation to self-reported: STI, having sex with another person when they were only supposed to have sex with their main partner, and consistent condom use. Over one-third of males (45%) reported any TDV; 42% reported sexual violence perpetration, 13% reported perpetrating physical violence against a dating/sexual partner and 11% reported psychological violence, including threats of physical or sexual violence. Approximately 15% of males reported having ever had an STI, one quarter reported having sex with another person when they were only supposed to have sex with their main partner and 36% reported consistent condom use (past 3 months). In adjusted logistic regression models, TDV perpetration was significantly associated with self-reports of an STI (OR=3.3; 95% CI 1.2 to 9.2) and having sex with another person when they were supposed to be only having sex with their main partner (OR=4.8; 95% CI 2.0 to 11.4). There was no significant association between TDV perpetration and consistent condom use. Current study findings are the first within the literature on adolescents to suggest that greater STI and sexual risk behaviours among male adolescents perpetrating TDV may be one mechanism explaining increased STI among female adolescents reporting TDV victimisation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Pathways from Racial Discrimination to Multiple Sexual Partners Among Male African American Adolescents

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Kogan, Steven M.; Yu, Tianyi; Allen, Kimberly A.; Pocock, Alexandra M.; Brody, Gene H.

2014-01-01

African American male adolescents’ involvement with multiple sexual partners has important implications for public health as well as for their development of ideas regarding masculinity and sexuality. The purpose of this study was to test hypotheses regarding the pathways through which racial discrimination affects African American adolescents’ involvement with multiple sexual partners. We hypothesized that racial discrimination would engender psychological distress, which would promote attitudes and peer affiliations conducive to multiple sexual partnerships. The study also examined the protective influence of parenting practices in buffering the influence of contextual stressors. Participants were 221 African American male youth who provided data at ages 16 and 18; their parents provided data on family socioeconomic disadvantages. Of these young men, 18.5% reported having 3 or more sexual partners during the past 3 months. Structural equation models indicated that racial discrimination contributed to sexual activity with multiple partners by inducing psychological distress, which in turn affected attitudes and peer affiliations conducive to multiple partners. The experience of protective parenting, which included racial socialization, closeness and harmony in parent-child relationships, and parental monitoring, buffered the influence of racial discrimination on psychological distress. These findings suggest targets for prevention programming and underscore the importance of efforts to reduce young men’s experience with racial discrimination. PMID:25937821

Prevalence of and Risk Factors for Male Sexual Abuse: The Case of South Korea

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Han, In Young; Lee, Yongwoo; Yoo, Seo Koo; Hong, Jun Sung

2011-01-01

This study examined the prevalence of and risk factors for sexual abuse of boys in South Korea by asking a national sample of 1,043 adult males whether they had experienced sexual abuse during childhood. The results indicate that 13.5% experienced at least one of the nine types of child sexual abuse assessed. In addition, the majority of the…

Função sexual de homens submetidos a transplante hepático Sexual function of males subjected to liver transplantation

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Júlio Cezar Uili Coelho

2003-01-01

Full Text Available OBJETIVO: Avaliar a qualidade de vida sexual masculina antes e depois do transplante hepático. MÉTODOS: Foi enviado questionário de avaliação para 56 doentes masculinos, que tinham idade superior a 18 anos e que sobreviveram mais de seis meses após o transplante hepático. O questionário continha 15 perguntas com cinco ou seis alternativas de resposta para mensurar a função sexual masculina segmentada por cinco componentes: função erétil, função orgástica, desejo sexual, satisfação com a relação sexual e satisfação com a vida sexual como um todo. As respostas geraram valores numéricos, os quais foram agrupados dentro de cada domínio e comparados antes e depois do transplante hepático. RESULTADOS: Vinte e cinco doentes responderam completamente o questionário. Todas os cinco componentes da função sexual melhoraram após o transplante hepático, sendo que o escore da função erétil aumentou de 21,12±8,07 para 26,52±5,22 (p=0,004, da função orgástica de 7,28±3,05 para 9,36±1,47 (p=0,008, da função desejo sexual de 6,64±2,58 para 8,68±1,35 (p=0,005, da satisfação com relação sexual de 9,16±3,83 para 12,52±2,65 (pBACKGROUND: Sexual dysfunction is very common in liver transplantation candidates. Our objective is to determine the sexual life quality of males before and after liver transplantation. METHODS: Questionnaire was sent to 56 males over 18 years of age with at least six-month survival after orthotopic liver transplantation. The self-administered questionnaire contained 15 questions with 5 or 6 alternatives to determine the male sexual function which may be divided into 5 domains: 1 erectile function; 2 orgasmic function; 3 sexual desire; 4 intercourse satisfaction; and 5 overall satisfaction with sexual life. Each answer received a score. Domains scores were computed by summing the scores for individual answers and they were compared before and after the liver transplantation. RESULTS: Twenty

Commercial Sexual Behaviors Among Male Rural-to-Urban Migrants in Western China: Implications for HIV Prevention.

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Li, Wenwei; Jiang, Junjun; Su, Jinming; Liang, Bingyu; Deng, Wei; Huang, Jiegang; Qin, Bo; Upur, Halmurat; Zhong, Chaohui; Wang, Qianqiu; Wang, Qian; Zang, Ning; Liao, Yanyan; Meng, Sirun; Ye, Li; Liang, Hao

2017-07-01

Rural-to-urban migrants are at high risk of HIV infection. The goal of this survey was to explore the commercial sexual behavior and condom use among male rural-to-urban migrants in western China. A cross-sectional survey on male rural-to-urban migrants in western China was conducted. Among all the subjects surveyed, 140 (7.4%) had commercial sexual behavior, which is associated with being aged older than 24 years, being of Han or other ethnic minorities, being divorced, separated, or widowed, having experienced drug abuse, having had heterosexual behavior, having had casual sexual partners, having had sex with a homosexual, and being from Xinjiang. A total of 31.4% of them never use condoms when buying sex. Not using condoms is associated with being from Chongqing, having a high school or above education, and having commercial sex monthly. Commercial sexual behavior and not using condoms are common among male rural-to-urban migrants in western China. Strategies and appropriate education should be developed to prevent HIV transmission due to high-risk sexual behaviors.

Sterility and Sexual Competitiveness of Tapachula-7 Anastrepha ludens Males Irradiated at Different Doses.

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Orozco-Dávila, Dina; Adriano-Anaya, Maria de Lourdes; Quintero-Fong, Luis; Salvador-Figueroa, Miguel

2015-01-01

A genetic sexing strain of Anastrepha ludens (Loew), Tapachula-7, was developed by the Mexican Program Against Fruit Flies to produce and release only males in programs where the sterile insect technique (SIT) is applied. Currently, breeding are found at a massive scale, and it is necessary to determine the optimum irradiation dose that releases sterile males with minimum damage to their sexual competitiveness. Under laboratory and field conditions, we evaluated the effects of gamma irradiation at doses of 0, 20, 40, 60 and 80 Gy on the sexual competitiveness of males, the induction of sterility in wild females and offspring survivorship. The results of the study indicate that irradiation doses have a significant effect on the sexual behavior of males. A reduction of mating capacity was inversely proportional to the irradiation dose of males. It is estimated that a dose of 60 Gy can induce more than 99% sterility in wild females. In all treatments, the degree of offspring fertility was correlated with the irradiation dose of the parents. In conclusion, the results of the study indicate that a dose of 60 Gy can be applied in sterile insect technique release programs. The application of this dose in the new genetic sexing strain of A. ludens is discussed.

The relationship between the FFM personality traits, state psychopathology, and sexual compulsivity in a sample of male college students.

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Pinto, Joana; Carvalho, Joana; Nobre, Pedro J

2013-07-01

Several studies have advocated a relationship between psychopathological features and sexual compulsivity. Such relationship is often found among individuals seeking help for out of control sexual behavior, suggesting that the association between psychological adjustment and sexual compulsivity may have a significant clinical value. However, a more complete approach to the topic of sexual compulsivity would also include the analysis of nonclinical samples as healthy individuals may be at risk of developing some features of hypersexuality in the future. The aim of this study was to explore the relationship between stable traits of personality, state psychopathology, and sexual compulsivity in a sample of male college students. Furthermore, the potential mediating role of state psychopathology in the relationship between personality traits and sexual compulsivity was tested. Participants completed the following measures: the NEO Five-Factor Inventory, the Brief Symptom Inventory, and the Compulsive Sexual Behavior Inventory-22. The sample included 152 male college students recruited in a Portuguese university using nonrandom methods. The measures were completed individually and anonymously. Findings on state psychopathology suggested that psychoticism may be one of the key dimensions associated with sexual compulsivity in male students. The personality traits of Neuroticism and Agreeableness were also significant predictors of sexual compulsivity. Findings on the mediating effects suggested that state psychopathology mediated the relationship between Neuroticism and sexual compulsivity but not between Agreeableness and sexual compulsivity. A psychopathological path (encompassing Neuroticism and state psychopathology) and a behavioral path (encompassing Agreeableness features) may be involved in sexual compulsivity as reported by a nonclinical sample of male students. © 2013 International Society for Sexual Medicine.

Male Sexual Quality Of Life Is Maintained Satisfactorily Throughout Life In The Amazon Rainforest.

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Teixeira, Thiago; Nazima, Maira; Hallak, Jorge

2018-06-01

The Amazon Rainforest is a cradle of biodiversity, where different ethnic groups have specific sexual habits. To define the average sexual quality of life of Amazonian men 18 to 69 years old, evaluate the influence of aging on their sexual function, and calculate the prevalence of premature ejaculation, delayed ejaculation, and hypoactive sexual desire disorder. A cross-sectional quantitative probability sample study was performed with a demographically representative population (N = 385), with data collected privately at participants' houses, including men who had been sexually active for a minimum of 6 months. The Male Sexual Quotient (MSQ) was used to measure sexual satisfaction and function. Statistical analysis was performed with SPSS 21.0 using the Kruskal-Wallis test (P quality of sexual life. MSQ scores. The response rate was 81.69%. The mean age was 36.00 ± 12.95 years, and most men had mixed ethnicity (63.11%), were self-employed (42.07%), had a monthly earned income of US$0 to US$460 (46.75%), and were single (36.10%). The mean MSQ score was 80.39 ± 12.14 (highly satisfied). None of the demographic characteristics showed a statistically significant influence on sexual satisfaction. The difference in quality of sexual life was statistically significant compared with age (P quality (P quality of sexual life. Sexual domains such as desire, partner satisfaction, and erection quality are related to the correlation between sexual quality of life and aging. However, the prevalence of premature ejaculation seems to be slightly higher than in other parts of the world. Teixeira T, Nazima M, Hallak J. Male Sexual Quality Of Life Is Maintained Satisfactorily Throughout Life In The Amazon Rainforest. Sex Med 2018;6:90-96. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Sexual orientation in males and the evolution of anisogamy.

Science.gov (United States)

Reed, Lawrence Ian

2010-02-01

How might homosexual orientation have evolved and been maintained? Several adaptationist explanations have been examined in attempt to reconcile the presence of same-sex sexual behaviors with traditional selection-based theory, showing little empirical support. The current paper presents a novel adaptationist explanation for the evolution and maintenance of same-sex sexual behaviors in males, both between- and within-species, related to the evolution of anisogamy. Under conditions of isogamy, sexual reproduction occurs between individuals with gametes of similar morphology. With the evolution of anisogamy came greater specificity on the types of individuals that would produce offspring when mated with (i.e. those with opposing gamete sizes). It is suggested that with this evolutionary change, a specified psychological adaptation orienting individuals primarily towards mating partners with newly opposing gamete sizes was then selected for. It is thus hypothesized that sexual orientation will vary along the anisogamy-isogamy continuum, with homosexual orientation being associated with closer approximations towards isogamy. This hypothesis leads to two specific predictions. First, in comparisons between species, the presence of same-sex sexual behaviors will be more likely to occur as sperm to egg ratios approach 1:1. Second, in comparisons within species, those individuals with greater sperm lengths will be more likely to exhibit same-sex sexual behaviors than those with lesser sperm lengths. Examination of the present hypothesis stands to greatly increase our knowledge of the selective forces shaping both biological and psychological evolution.

[Sexual behavior and sources of information about sex among male adolescents: An 8-year follow-up].

Science.gov (United States)

Korkmaz Cetin, Saniye; Bildik, Tezan; Erermiş, Serpil; Demiral, Nagehan; Ozbaran, Burcu; Tamar, Müge; Aydin, Cahide

2008-01-01

This study aimed to determine the changes over time in sexual attitude and behavior among adolescents, and to measure the effect of sources information about sex on these changes. This study was conducted in 2 stages, the first in 1996 and the second in 2004. In all, 392 male tenth grade students (150 in the first stage and 242 in the second stage) were evaluated. A personal information questionnaire developed by the authors was used to collect sociodemographic data, including sexual behavior, sexual attitude, and sources of information about sex. The findings show that there was a significant increase in intercourse and flirting behavior from 1996 to 2004, although no significant difference in masturbation was observed. Additionally, the number of male adolescents that reported family and pornographic films as their sources of information about sex increased 1.6-fold and 2.9-fold, respectively. A significant relationship between watching pornographic films and engaging in sexual intercourse was noted. The number of male adolescents age mean 16, engaging in sexual intercourse increased between 1996 and 2004. Pornographic films were observed to be the most common source of information about sex and also predicted the probability of adolescents having sex. Findings that indicate the need for better and more accurate sources of information about sex. The availability of good quality information about sex is critical to the development of the sexual identity and mental health of male adolescents.

Effects of fenfluramine and para-chloroamphetamine on sexual behavior of male rats.

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Foreman, M M; Hall, J L; Love, R L

1992-01-01

The present studies have evaluated the effects of pharmacologically induced release serotonin on sexual responses of male rats during exposure to a sexually receptive female rat. Following acute administration of fenfluramine or para-chloroamphetamine (PCA), significant dose-related decreases in copulatory rate and copulatory efficiency, and increases in ejaculatory latency were observed. These effects were not observed when the animals were pretreated with LY53857, a 5-HT1c/2 antagonist. These studies indicate that acute release of serotonin evoked by these releasing agents has inhibitory effects on sexual sexual drive, capacity to achieve erection and threshold for ejaculation, and these effects are mediated by either the 5-HT1c or 5-HT2 receptor.

Sexual Dysfunction and Hyperprolactinemia in Male Psychotic Inpatients: A Cross-Sectional Study

Directory of Open Access Journals (Sweden)

Erik Johnsen

2011-01-01

Full Text Available Introduction. Sexual dysfunction (SD and hyperprolactinemia are frequently reported in patients with psychotic disorders and have the potential for severe complications but investigations in males are particularly scarce. The primary aims were to determine the prevalence of SD and hyperprolactinemia in male patients and to investigate whether associations exist between SD and prolactin levels. Methods. Cross-sectional data were obtained at discharge from the hospital or 6 weeks after admittance for patients acutely admitted for psychosis and treated with a second-generation antipsychotic drug. Results. Half the patients reported diminished sexual desire and more than a third reported erectile and ejaculatory dysfunctions with no differences among the drugs. More than half the sample was hyperprolactinemic. No association was found between prolactin levels and SD. Conclusion. High rates of SD and hyperprolactinemia were found in male patients and should be a treatment target. SD and hyperprolactinemia were not correlated.

Vitamin D and Male Sexual Function: A Transversal and Longitudinal Study.

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Tirabassi, Giacomo; Sudano, Maurizio; Salvio, Gianmaria; Cutini, Melissa; Muscogiuri, Giovanna; Corona, Giovanni; Balercia, Giancarlo

2018-01-01

The effects of vitamin D on sexual function are very unclear. Therefore, we aimed at evaluating the possible association between vitamin D and sexual function and at assessing the influence of vitamin D administration on sexual function. We retrospectively studied 114 men by evaluating clinical, biochemical, and sexual parameters. A subsample ( n = 41) was also studied longitudinally before and after vitamin D replacement therapy. In the whole sample, after performing logistic regression models, higher levels of 25(OH) vitamin D were significantly associated with high values of total testosterone and of all the International Index of Erectile Function (IIEF) questionnaire parameters. On the other hand, higher levels of total testosterone were positively and significantly associated with high levels of erectile function and IIEF total score. After vitamin D replacement therapy, total and free testosterone increased and erectile function improved, whereas other sexual parameters did not change significantly. At logistic regression analysis, higher levels of vitamin D increase (Δ-) were significantly associated with high values of Δ-erectile function after adjustment for Δ-testosterone. Vitamin D is important for the wellness of male sexual function, and vitamin D administration improves sexual function.

Empowerment evaluation with programs designed to prevent first-time male perpetration of sexual violence.

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Noonan, Rita K; Gibbs, Deborah

2009-01-01

This special issue captures several threads in the ongoing evolution of sexual violence prevention. The articles that follow examine an empowerment evaluation process with four promising programs dedicated to preventing first-time male perpetration of sexual violence, as well as evaluation findings. Both the evaluation approach and the programs examined shed light on how sexual violence prevention can continue to be improved in the future.

Childhood experiences of incarcerated male child sexual abusers.

Science.gov (United States)

Garrett, Linda H

2010-10-01

While numerous efforts have been made to understand the impact of child sexual abuse, little has been done to examine the childhood experiences of those who abuse children. Child sexual abusers have been studied from quantitative perspectives using behavioral checklists, parental-bonding surveys, and sexual history questionnaires. The purpose of this study was to explore incarcerated child sexual abusers' recollections of their childhood experiences using the descriptive existential lens of phenomenology. Eight incarcerated male child sexual abusers described their childhood from existential perspectives of lived space, lived other, lived body, and lived time via face-to-face semi-structured interviews. Analysis was accomplished through the qualitative, descriptive method of Max van Manen. Rich descriptions of the participants' insights into their daily childhood life experiences that shaped their self-concepts and contributed to their adult behaviors were gathered. Four major themes were identified: (1) failure to root, (2) what you see is what you learn, (3) stupid is as stupid does, and (4) life's moments. Data from this study suggest that the experiences of childhood significantly contribute to an adult self-concept that can be distorted by the lack of a secure home space, maladaptive relationships, internalization of inappropriate behavior, and a lack of significant family development. This study explores the psychosocial and behavioral consequences of early childhood experiences. The findings support the need for family and psychological mental health nurse practitioners to be more aware of early home environments; improve their assessment of children's developing self-concept and the potential for abusive relationships.

Sexual health and quality of life among male veterans with intestinal ostomies.

Science.gov (United States)

Symms, Michelle R; Rawl, Susan M; Grant, Marcia; Wendel, Christopher S; Coons, Stephen Joel; Hickey, Sara; Baldwin, Carol M; Krouse, Robert S

2008-01-01

This secondary analysis was conducted to expand our understanding of the challenges men with ostomies face regarding intimate relationships and sexual functioning. We examined quantitative and qualitative data to examine sexual functioning, intimate relationships, and health-related quality of life (HR-QOL) among military veterans who are living with an intestinal stoma. Three Veterans Health Administration sites. Four hundred eighty-one male veterans. Case-control, mixed-methods design; cases were those who had ostomies for at least 2 months, and controls had a similar major intestinal surgical procedure that did not result in an ostomy. Quantitative and qualitative data on sexual functioning, relationships, and other dimensions of HR-QOL were collected using the modified City of Hope Quality of Life-Ostomy questionnaire. The overall response rate was 49%. Prevalence of erectile dysfunction was significantly higher among ostomates compared with controls (P ostomies reported being sexually active before surgery compared with controls (P ostomy group (P = .015). Compared with veterans with ostomies who did not resume sexual activity after surgery, those who were sexually active reported a higher total HR-QOL score and higher scores on all 4 modified City of Hope Quality of Life-Ostomy dimensions (psychological, social, physical, and spiritual well-being). Veterans with ostomies who had resumed sexual activity after their ostomy also reported that their ostomy had caused significantly less interference with social activities, less isolation, less interference with their personal relationships, and less interference with their ability to be intimate. These men also reported less difficulty adjusting to the ostomy. Results of qualitative analyses showed that problems with intimacy and sexual function are among the greatest challenges faced by ostomates. Presence of an ostomy was associated with lower rates of sexual activity and higher erectile dysfunction. The lower

Behavioural ecology: transient sexual mimicry leads to fertilization.

Science.gov (United States)

Hanlon, Roger T; Naud, Marié-Jose; Shaw, Paul W; Havenhand, Jon N

2005-01-20

Sexual mimicry among animals is widespread, but does it impart a fertilization advantage in the widely accepted 'sneak-guard' model of sperm competition? Here we describe field results in which a dramatic facultative switch in sexual phenotype by sneaker-male cuttlefish leads to immediate fertilization success, even in the presence of the consort male. These results are surprising, given the high rate at which females reject copulation attempts by males, the strong mate-guarding behaviour of consort males, and the high level of sperm competition in this complex mating system.

Higher variability in the number of sexual partners in males can contribute to a higher prevalence of sexually transmitted diseases in females

DEFF Research Database (Denmark)

Oliveira, Rodrigo Gouveia; Pedersen, Anders Gorm

2009-01-01

, and on the probability of disease transmission. We note that in addition to humans, the variance phenomenon described here is likely to play a role for sexually transmitted diseases in other species also. We also show, again by examining published, empirical data, that the female to male prevalence ratio increases...... of sexually transmitted diseases: compared to the situation where the genders have identical sex partner distributions, men will reach a lower equilibrium value, while women will stay at the same level (meaning that female prevalence becomes higher than male). We carefully analyse model behaviour and derive...... with the overall prevalence of a sexually transmitted disease (i.e., the more widespread the disease, the more women are affected). We suggest that this pattern may be caused by the effect described above in highly prevalent sexually transmitted diseases, while its impact in low-prevalence epidemics is surpassed...

Studies on thyroid activity at sexual maturity in the male and female Bengal goats

International Nuclear Information System (INIS)

Varshney, V.P.; Pande, J.K.; Sanwal, P.C.

1980-01-01

Thyroid activity at sexual maturity in the male and female Black Bengal goats was investigated. No change could be recorded at the attainment of sexual maturity in either of the sexes. The cyclic female goats also failed to reflect any change in the thyroid activity during any phase of the oestrous cycle. Again the male goats also failed to reflect any differences in the thyroid activity from the females, either during their immature, or during their mature life. The observations presented thus reflect that the thyroid activity in goats is not influenced by the attainments of sexual maturity or by the sex, in this species. The thyroid gland activity was assessed by using the in vitro technique of triiodothyronine- 125 I uptake by resin. (author)

Sim1 Neurons Are Sufficient for MC4R-Mediated Sexual Function in Male Mice.

Science.gov (United States)

Semple, Erin; Hill, Jennifer W

2018-01-01

Sexual dysfunction is a poorly understood condition that affects up to one-third of men around the world. Existing treatments that target the periphery do not work for all men. Previous studies have shown that central melanocortins, which are released by pro-opiomelanocortin neurons in the arcuate nucleus of the hypothalamus, can lead to male erection and increased libido. Several studies specifically implicate the melanocortin 4 receptor (MC4R) in the central control of sexual function, but the specific neural circuitry involved is unknown. We hypothesized that single-minded homolog 1 (Sim1) neurons play an important role in the melanocortin-mediated regulation of male sexual behavior. To test this hypothesis, we examined the sexual behavior of mice expressing MC4R only on Sim1-positive neurons (tbMC4Rsim1 mice) in comparison with tbMC4R null mice and wild-type controls. In tbMC4Rsim1 mice, MC4R reexpression was found in the medial amygdala and paraventricular nucleus of the hypothalamus. These mice were paired with sexually experienced females, and their sexual function and behavior was scored based on mounting, intromission, and ejaculation. tbMC4R null mice showed a longer latency to mount, a reduced intromission efficiency, and an inability to reach ejaculation. Expression of MC4R only on Sim1 neurons reversed the sexual deficits seen in tbMC4R null mice. This study implicates melanocortin signaling via the MC4R on Sim1 neurons in the central control of male sexual behavior. Copyright © 2018 Endocrine Society.

A change in competitive context reverses sexual selection on male size.

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Kasumovic, M M; Andrade, M C B

2009-02-01

In studies of sexual selection, larger size is often argued to increase male fitness, and relatively smaller males are explained by genetic and/or environmental variation. We demonstrate that a size-development life-history trade-off could underlie the maintenance of a broad, unimodal distribution of size in male redback spiders (Latrodectus hasselti). Larger males are superior in direct competition, but redback males mature rapidly at small size in the presence of females. In field enclosures, we simulated two competitive contexts favouring development of divergent male sizes. Relatively smaller males lost when competing directly, but had 10 times higher fitness than relatively larger males when given the temporal advantage of rapid development. Linear selection gradients confirmed the reversal of selection on size, showing that it is critical to consider life-history decisions underlying the development of traits related to fitness.

Conditioned same-sex partner preference in male rats is facilitated by oxytocin and dopamine: effect on sexually dimorphic brain nuclei.

Science.gov (United States)

Triana-Del Rio, Rodrigo; Tecamachaltzi-Silvarán, Miriam B; Díaz-Estrada, Victor X; Herrera-Covarrubias, Deissy; Corona-Morales, Aleph A; Pfaus, James G; Coria-Avila, Genaro A

2015-04-15

Conditioned same-sex partner preference can develop in male rats that undergo cohabitation under the effects of quinpirole (QNP, D2 agonist). Herein, we assessed the development of conditioned same-sex social/sexual preference in males that received either nothing, saline, QNP, oxytocin (OT), or QNP+OT during cohabitation with another male (+) or single-caged (-). This resulted in the following groups: (1) Intact-, (2) Saline+, (3) QNP-, (4) OT-, (5) QNP+, (6) OT+ and (7) QNP/OT+. Cohabitation occurred during 24h in a clean cage with a male partner that bore almond scent on the back as conditioned stimulus. This was repeated every 4 days for a total of three trials. Social and sexual preference were assessed four days after the last conditioning trial in a drug-free test in which experimental males chose between the scented familiar male and a novel sexually receptive female. Results showed that males from groups Intact-, Saline+, QNP- and OT- displayed a clear preference for the female (opposite-sex), whereas groups QNP+, OT+ and QNP/OT+ displayed socio/sexual preference for the male partner (same-sex). In Experiment 2, the brains were processed for Nissl dye and the area size of two sexually dimorphic nuclei (SDN-POA and SON) was compared between groups. Males from groups OT-, OT+ and QNP/OT+ expressed a smaller SDN-POA and groups QNP+ and QNP/OT+ expressed a larger SON. Accordingly, conditioned same-sex social/sexual partner preference can develop during cohabitation under enhanced D2 or OT activity but such preference does not depend on the area size of those sexually dimorphic nuclei. Copyright © 2015 Elsevier B.V. All rights reserved.

Standards for Clinical Trials in Male and Female Sexual Dysfunction: I. Phase I to Phase IV Clinical Trial Design.

Science.gov (United States)

Fisher, William A; Gruenwald, Ilan; Jannini, Emmanuele A; Lev-Sagie, Ahinoam; Lowenstein, Lior; Pyke, Robert E; Reisman, Yakov; Revicki, Dennis A; Rubio-Aurioles, Eusebio

2016-12-01

This series of articles outlines standards for clinical trials of treatments for male and female sexual dysfunctions, with a focus on research design and patient-reported outcome assessment. These articles consist of revision, updating, and integration of articles on standards for clinical trials in male and female sexual dysfunction from the 2010 International Consultation on Sexual Medicine developed by the authors as part of the 2015 International Consultation on Sexual Medicine. We are guided in this effort by several principles. In contrast to previous versions of these guidelines, we merge discussion of standards for clinical trials in male and female sexual dysfunction in an integrated approach that emphasizes the common foundational practices that underlie clinical trials in the two settings. We present a common expected standard for clinical trial design in male and female sexual dysfunction, a common rationale for the design of phase I to IV clinical trials, and common considerations for selection of study population and study duration in male and female sexual dysfunction. We present a focused discussion of fundamental principles in patient- (and partner-) reported outcome assessment and complete this series of articles with specific discussions of selected aspects of clinical trials that are unique to male and to female sexual dysfunction. Our consideration of standards for clinical trials in male and female sexual dysfunction attempts to embody sensitivity to existing and new regulatory guidance and to address implications of the evolution of the diagnosis of sexual dysfunction that have been brought forward in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. The first article in this series focuses on phase I to phase IV clinical trial design considerations. Subsequent articles in this series focus on the measurement of patient-reported outcomes, unique aspects of clinical trial design for men, and unique aspects of clinical

TRAINING IN MALE SEXUAL AND REPRODUCTIVE HEALTH FOR A PRIMARY CARE PHYSICIAN

OpenAIRE

SHAIFUL BI

2008-01-01

In 2006, I was awarded a scholarship from Universiti Sains Malaysia for Fellowship training at Monash University (MU) for one year. The objective of the training programme was to develop knowledge and skills in several areas, including androgen deficiency, male infertility, prostate disease, testicular tumours, sexual dysfunction and sexually transmitted diseases. The training programme consisted of attachments with clinical specialists, completion of a course work module and a research proje...

Ghrelin and GHS-R1A signaling within the ventral and laterodorsal tegmental area regulate sexual behavior in sexually naïve male mice.

Science.gov (United States)

Prieto-Garcia, Luna; Egecioglu, Emil; Studer, Erik; Westberg, Lars; Jerlhag, Elisabet

2015-12-01

In addition to food intake and energy balance regulation, ghrelin mediate the rewarding and motivational properties of palatable food as well as addictive drugs. The ability of ghrelin to regulate reinforcement involves the cholinergic-dopaminergic reward link, which encompasses a cholinergic projection from the laterodorsal tegmental area (LDTg) to the ventral tegmental area (VTA) together with mesolimbic dopaminergic projections from the VTA to the nucleus accumbens (NAc). Recently, systemic ghrelin was shown to regulate sexual behavior and motivation in male mice via dopamine neurotransmission. The present study therefore elucidates the role of ghrelin and ghrelin receptor (GHS-R1A) antagonist treatment within NAc, VTA or LDTg for sexual behavior in sexually naïve male mice. Local administration of the GHSR-1A antagonist, JMV2959, into the VTA or LDTg was found to reduce the preference for female mice, the number of mounts and the duration of mounting as well as to prolong the latency to mount. This was further substantiated by the findings that ghrelin administration into the VTA or LDTg increased the number of mounts and the duration of mounting and decreased the latency to mount. Moreover, ghrelin administered into the LDTg increased the preference for female mice. Accumbal administration of ghrelin increased whereas GHS-R1A antagonist decreased the intake of palatable food, but did not alter sexual behavior. In males exposed to sexual interaction, systemic administration of ghrelin increases whereas JMV2959 decreases the turnover of dopamine in the VTA. These data suggest that ghrelin signaling within the tegmental areas is required for sexual behavior in sexually naïve male mice. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Sexual selection protects against extinction.

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

2015-06-25

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

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

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

2013-01-01

Background In sub-Saharan Africa the population prevalence of men who have sex with men (MSM) is unknown, as is the population prevalence of male-on-male sexual violence, and whether male-on-male sexual violence may relate to HIV risk. This paper describes lifetime prevalence of consensual male–male sexual behavior and male-on-male sexual violence (victimization and perpetration) in two South African provinces, socio-demographic factors associated with these experiences, and associations with HIV serostatus. Methods and Findings In a cross-sectional study conducted in 2008, men aged 18–49 y from randomly selected households in the Eastern Cape and KwaZulu-Natal provinces provided anonymous survey data and dried blood spots for HIV serostatus assessment. Interviews were completed in 1,737 of 2,298 (75.6%) of enumerated and eligible households. From these households, 1,705 men (97.1%) provided data on lifetime history of same-sex experiences, and 1,220 (70.2%) also provided dried blood spots for HIV testing. 5.4% (n = 92) of participants reported a lifetime history of any consensual sexual activity with another man; 9.6% (n = 164) reported any sexual victimization by a man, and 3.0% (n = 51) reported perpetrating sexual violence against another man. 85.0% (n = 79) of men with a history of consensual sex with men reported having a current female partner, and 27.7% (n = 26) reported having a current male partner. Of the latter, 80.6% (n = 21/26) also reported having a female partner. Men reporting a history of consensual male–male sexual behavior are more likely to have been a victim of male-on-male sexual violence (adjusted odds ratio [aOR] = 7.24; 95% CI 4.26–12.3), and to have perpetrated sexual violence against another man (aOR = 3.10; 95% CI 1.22–7.90). Men reporting consensual oral/anal sex with a man were more likely to be HIV+ than men with no such history (aOR = 3.11; 95% CI 1.24–7.80). Men who had raped a man

Chemical communication, sexual selection, and introgression in wall lizards.

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MacGregor, Hannah E A; Lewandowsky, Rachel A M; d'Ettorre, Patrizia; Leroy, Chloé; Davies, Noel W; While, Geoffrey M; Uller, Tobias

2017-10-01

Divergence in communication systems should influence the likelihood that individuals from different lineages interbreed, and consequently shape the direction and rate of hybridization. Here, we studied the role of chemical communication in hybridization, and its contribution to asymmetric and sexually selected introgression between two lineages of the common wall lizard (Podarcis muralis). Males of the two lineages differed in the chemical composition of their femoral secretions. Chemical profiles provided information regarding male secondary sexual characters, but the associations were variable and inconsistent between lineages. In experimental contact zones, chemical composition was weakly associated with male reproductive success, and did not predict the likelihood of hybridization. Consistent with these results, introgression of chemical profiles in a natural hybrid zone resembled that of neutral nuclear genetic markers overall, but one compound in particular (tocopherol methyl ether) matched closely the introgression of visual sexual characters. These results imply that associations among male chemical profiles, sexual characters, and reproductive success largely reflect transient and environmentally driven effects, and that genetic divergence in chemical composition is largely neutral. We therefore suggest that femoral secretions in wall lizards primarily provide information about residency and individual identity rather than function as sexual signals. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

Prevalence rates of male and female sexual violence perpetrators in a national sample of adolescents.

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Ybarra, Michele L; Mitchell, Kimberly J

2013-12-01

IMPORTANCE Sexual violence can emerge in adolescence, yet little is known about youth perpetrators-especially those not involved with the criminal justice system. OBJECTIVE To report national estimates of adolescent sexual violence perpetration and details of the perpetrator experience. DESIGN, SETTING, AND PARTICIPANTS Data were collected online in 2010 (wave 4) and 2011 (wave 5) in the national Growing Up With Media study. Participants included 1058 youths aged 14 to 21 years who at baseline read English, lived in the household at least 50% of the time, and had used the Internet in the last 6 months. Recruitment was balanced on youths' biological sex and age. MAIN OUTCOMES AND MEASURES Forced sexual contact, coercive sex, attempted rape, and completed rape. RESULTS Nearly 1 in 10 youths (9%) reported some type of sexual violence perpetration in their lifetime; 4% (10 females and 39 males) reported attempted or completed rape. Sixteen years old was the mode age of first sexual perpetration (n = 18 [40%]). Perpetrators reported greater exposure to violent X-rated content. Almost all perpetrators (98%) who reported age at first perpetration to be 15 years or younger were male, with similar but attenuated results among those who began at ages 16 or 17 years (90%). It is not until ages 18 or 19 years that males (52%) and females (48%) are relatively equally represented as perpetrators. Perhaps related to age at first perpetration, females were more likely to perpetrate against older victims, and males were more likely to perpetrate against younger victims. Youths who started perpetrating earlier were more likely than older youths to get in trouble with caregivers; youths starting older were more likely to indicate that no one found out about the perpetration. CONCLUSIONS AND RELEVANCE Sexual violence perpetration appears to emerge earlier for males than females, perhaps suggesting different developmental trajectories. Links between perpetration and violent sexual

Heterosexual men's anger in response to male homosexuality: effects of erotic and non-erotic depictions of male-male intimacy and sexual prejudice.

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Hudepohl, Adam D; Parrott, Dominic J; Zeichner, Amos

2010-01-01

The present study compared effects of erotic and non-erotic depictions of male-male intimacy on the experience of anger in heterosexual men. Data came from three independent laboratory studies designed to elicit anger in response to erotic or non-erotic depictions of male-male and male-female intimacy. All participants completed a measure of sexual prejudice and anger was assessed before and after viewing the erotic or non-erotic video. Among high-prejudiced men, viewing erotic and non-erotic intimate behavior between two men elicited significant increases in anger relative to viewing comparable behavior between a male-female dyad. In contrast, among low-prejudiced men, viewing erotic, but not non-erotic, intimate behavior between two men elicited significant increases in anger relative to viewing comparable behavior between a male-female dyad. Implications for understanding heterosexual men's anger, and aggression, toward gay men were discussed.

Heterosexual Men's Anger in Response to Male Homosexuality: Effects of Erotic and Non-Erotic Depictions of Male-Male Intimacy and Sexual Prejudice

Science.gov (United States)

Hudepohl, Adam D.; Parrott, Dominic J.; Zeichner, Amos

2010-01-01

The present study compared effects of erotic and non-erotic depictions of male-male intimacy on the experience of anger in heterosexual men. Data came from three independent laboratory studies designed to elicit anger in response to erotic or non-erotic depictions of male-male and male-female intimacy. All participants completed a measure of sexual prejudice and anger was assessed before and after viewing the erotic or non-erotic video. Among high-prejudiced men, viewing erotic and non-erotic intimate behavior between two men elicited significant increases in anger relative to viewing comparable behavior between a male-female dyad. In contrast, among low-prejudiced men, viewing erotic, but not non-erotic, intimate behavior between two men elicited significant increases in anger relative to viewing comparable behavior between a male-female dyad. Implications for understanding heterosexual men's anger, and aggression, toward gay men were discussed. PMID:20818528

Sexual Orientation Disparities in Human Papillomavirus Vaccination in a Longitudinal Cohort of U.S. Males and Females.

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Charlton, Brittany M; Reisner, Sari L; Agénor, Madina; Gordon, Allegra R; Sarda, Vishnudas; Austin, S Bryn

2017-06-01

This study sought to examine how human papillomavirus (HPV) vaccination may differ across sexual orientation groups (e.g., bisexuals compared to heterosexuals)-particularly in boys and men, about whom little is known. Data were from a prospective cohort of 10,663 U.S. females and males enrolled in the Growing Up Today Study followed from 1996 to 2014. Participants were aged 11-24 years when the vaccine was approved for females in 2006 and 14-27 years when approved for males in 2009. In addition to reporting sexual orientation identity/attractions, participants reported sex of lifetime sexual partners. Log-binominal models were used to examine HPV vaccination across sexual orientation groups. Among females, 56% received ≥1 dose. In contrast, 8% of males obtained ≥1 dose; HPV vaccination initiation was especially low among completely heterosexual males. After adjusting for potential confounders, completely heterosexual (risk ratio [RR]; 95% confidence interval [CI]: 0.45 [0.30-0.68]) and mostly heterosexual (RR; 95% CI: 0.44 [0.25-0.78]) males were half as likely to have received even a single dose compared to gay males. Compared to lesbians, no differences were observed for completely heterosexual or bisexual females, but mostly heterosexual females were 20% more likely to have received at least one dose. HPV vaccination rates in the U.S. are strikingly low and special attention is needed for boys and men, especially those who do not identify as gay. Vaccinating everyone, regardless of sex/gender and/or sexual orientation, will not only lower that individual's susceptibility but also decrease transmission to partners, females and/or males, to help eradicate HPV through herd immunity.

Prevalence and pattern of misconceptions about semen loss and sexual prowess among male medical interns

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Ajish G Mangot

2017-01-01

Full Text Available Introduction: Sexual misconceptions have been around in India for a very long time. Growing liberal attitudes toward sex and sexual permissiveness can be expected to occur in the context of improved sexual knowledge among people. However, sexual myths continue to remain rampant. Therefore, the present study was planned with the aim to assess the level of sexual misconceptions regarding semen loss prevalent among male medical interns. Participants and Methods: This was a cross-sectional study among unmarried male medical students doing an internship. Eighty-one interns were recruited after fulfilling predecided inclusion/exclusion criteria and were asked to complete a specially made questionnaire to assess their sexual beliefs anonymously in complete privacy. Responses were analyzed using frequency distribution. Results: Seventy-nine percent of the participants believed that loss of semen can lead to reduction in the size of the penis, while 44.44% (n = 36 believed that it leads to sexual weakness, 56.8% (n = 46 believed it can lead to physical weakness, and 56.8% (n = 46 believed that excess masturbation can decrease sexual prowess. Discussion: This study helps bring to light the prevalence of sexual misconceptions among medical interns in spite of reaching a stage where they are expected to have sound conceptual, theoretical, and practical knowledge about sexual health and wellbeing. There is a dearth of national and international studies exploring the sociocultural aspects of sexuality specifically among medical students. The findings from this study are expected to stimulate researchers and academicians into further exploring the aspect of sexuality among the young medical fraternity.

Perceptions about medical male circumcision and sexual behaviours of adults in rural Uganda: a cross sectional study.

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Mukama, Trasias; Ndejjo, Rawlance; Musinguzi, Geofrey; Musoke, David

2015-01-01

Medical male circumcision is currently recognized as an additional important HIV preventive intervention to reduce the risk of heterosexually acquired HIV infection in men. However, sexual behaviours after medical circumcision can potentially reduce the expected benefits of the practice. This study explored the perceptions about medical male circumcision and sexual behaviours of adults in Kayunga district, Uganda. A cross-sectional study was carried out among 393 respondents using a semi structured questionnaire. In addition, four focus group discussions were conducted. Quantitative data was analysed using STATA 12. Univariate, bivariate and multivariate analyses were carried out. Qualitative data was analysed thematically. The study established various perceptions about medical male circumcision and sexual behaviours. Majority 247 (64.5%) did not perceive circumcision as a practice that can lead men to have multiple sexual partners. Males were 3 times more likely to think that circumcision would lead to having multiple sexual partners than females (AOR=2.99, CI: 1.93-4.61). Only 89 (23.2%) believed that circumcision would lead to complacency and compromise the use of condoms to prevent against infection with HIV. Respondents who had education above primary were less likely to think that circumcision would compromise the use of condoms (AOR=0.49, CI: 0.31- 0.79). The perception that circumcised youths were less likely to abstain from sexual intercourse was less held among those with education above primary (AOR=0.58, CI: 0.37-0.91) and those older than 30 years (AOR=0.59, CI: 0.38-0.92). There were gaps in knowledge and negative perceptions about MMC in the study community. Measures are needed to avert the negative perceptions by equipping communities with sufficient, accurate and consistent information about medical male circumcision and sexual behaviour.

Magnetic resonance imaging of male and female genitals during coitus and female sexual arousal

NARCIS (Netherlands)

Schultz, WW; van Andel, P; Sabelis, [No Value; Mooyaart, E

1999-01-01

Objective To find out whether taking images of the male and female genitals during coitus is feasible and to find out whether former and current ideas about the anatomy during sexual intercourse and during female sexual arousal are based on assumptions or on facts. Design Observational study Setting

Abnormal Sexual Behavior in an Adult Male with Obsessive Compulsive Disorder

OpenAIRE

Raguraman, Janakiraman; Priyadharshini, Kothai R.; Chandrasekaran, R.; Vijaysagar, John

2004-01-01

A male patient with homosexual obsession in obsessive compulsive disorder shows a better outcome following a combination of pharmacotherapy and psychotherapy. This case report emphasizes the importance of combination therapy in obsessive compulsive disorder with abnormal sexual impulses and behavior.

Associations Between Sexual Risk-Related Behaviors and School-Based Education on HIV and Condom Use for Adolescent Sexual Minority Males and Their Non-Sexual-Minority Peers.

Science.gov (United States)

Rasberry, Catherine N; Condron, D Susanne; Lesesne, Catherine A; Adkins, Susan Hocevar; Sheremenko, Ganna; Kroupa, Elizabeth

2018-01-01

With HIV and sexually transmitted disease (STD) rates disproportionately high among adolescent sexual minority males (ASMM), it is important to understand how school-based sexual health education may relate to sexual risk-related behavior among this population. This analysis explores reported HIV/AIDS- and condom-related education and sexual risk-related behaviors among ASMM and their adolescent non-sexual-minority male (non-ASMM) peers. Students (n = 11,681) from seven Florida high schools completed paper-and-pencil questionnaires. A matched analytic sample of ASMM and non-ASMM students was created by using propensity score-matching techniques (n = 572). Logistic regressions controlling for individual and school characteristics examined reporting having been taught about AIDS or HIV in school, having been taught in school about using condoms, condom use at last sex, HIV/STD testing, and associations between these variables. Compared with matched non-ASMM peers, ASMM students were less likely to report having been taught about AIDS or HIV in school (odds ratio [OR] = 0.58, P = 0.04) and having used a condom at last sex (OR = 0.39, P condoms. Among non-ASMM, reporting having been taught in school about using condoms was associated with a greater likelihood of condom use at last sex (OR = 4.78, P education and differential associations between condom-related education and condom use in ASMM and non-ASMM suggest that sexual health education in schools may not be resonating with ASMM and non-ASMM in the same way.

Iniciação sexual de homens adolescentes The onset of sexual activity in male adolescents

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Daniela Gubert

2008-12-01

Full Text Available Trata-se de pesquisa quantitativa que teve como objetivo investigar a iniciação sexual de adolescentes do sexo masculino em Concórdia, Santa Catarina. Participaram da mesma 340 adolescentes do sexo masculino, com idades entre 14 e 19 anos, que freqüentavam o ensino médio em seis instituições de ensino do município de Concórdia, que aceitaram participar e que trouxeram o Termo de Consentimento Livre e Esclarecido assinado pelos pais ou responsáveis. Destes, 69,7% afirmaram ter relações sexuais, sendo que a média de idade da primeira relação foi de 14,4 anos, menor que a média nacional de 15 anos. A primeira relação sexual ocorreu com uma ficante para 45,1% e 64,2% afirmaram que o principal motivo para a mesma foi vontade/tesão. A maioria (74,2% qualificou a experiência como boa ou muito boa. O uso da camisinha foi apontado como método utilizado na primeira relação sexual por 73,8% dos adolescentes e como método usado em todas as relações por 72,5%. Alguns adolescentes relataram não conversar sobre sexualidade, mas a maioria aponta os amigos como principal fonte de informações sobre sexo. Frente ao exposto, fica claro que apesar de terem sua primeira relação sexual cada vez mais precocemente, o diálogo sobre prevenção tem surtido efeito, o que é reforçado pelo uso expressivo do preservativo entre os adolescentes.This quantitative study aimed to investigate the onset of sexual activity in male adolescents from Concordia, Santa Catarina, Brazil. The studied sample consisted of a total of 340 14-19-year-old male adolescents attending secondary school in six local educational institutions, who accepted to answer the questionnaire and whose parents signed the Free and Informed Consent. From these, 69,7% affirmed that they already had sexual relations; the mean age at the first relation was 14,4, lower than national average of 15 years. The first sexual relation occurred with a date in the case of 45,1% and 64

Stimuli eliciting sexual arousal in males who offend adult women: an experimental study.

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Kolárský, A; Madlafousek, J; Novotná, V

1978-03-01

The sexually arousing effects of short film scenes showing a naked actress's seductive behavior were phalloplethysmographically measured in 14 sexual deviates. These were males who had offended adult women, predominantly exhibitionists. Controls were 14 normal men. Deviates responded positively to the scenes and differentiated strong and weak seduction scenes similarly to normals. Consequently, the question arises of why deviates avoid their victim's erotic cooperation and why they do not offend their regular sexual partners. Post hoc analysis of five scenes which elicited a strikingly higher response in deviates than in normals suggested that these scenes contained reduced seductive behavior but unrestrained presentation of the genitals. This finding further encourages the laboratory study of stimulus conditions for abnormal sexual arousal which occurs during the sexual offense.

Mating success of males with and without wing patch in Drosophila biarmipes.

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Hegde, S N; Chethan, B K; Krishna, M S

2005-10-01

Some males of D. biarmipes--synonym of D. rajasekari and D. raychaudhuri have a black patch on the wing. The patch extends from the apical margin of wing to the third longitudinal vein. Field and laboratory studies have been carried out in D. biarmipes to study role of male's wing patch in mating success. The field study shows that nature favors D. biarmipes males with patch. Although males without patch mated, males with patch have higher mating success suggesting the role of wing patch during courtship. Further, among mating males, males with patch had longer wings than males without patch. During courtship, males with patch oriented and mated faster; performed courtship acts such as tapping, scissoring, vibration, licking and twist dance more times than males without patch in both competitive and non-competitive situations. The results indicate that there is a casual relationship between the presence of wing patch, mating speed and success. Also there is a correlation between presence of wing patch, size of the flies and mating success.

Ejaculate economics: testing the effects of male sexual history on the trade-off between sperm and immune function in Australian crickets.

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Damian K Dowling

Full Text Available Trade-offs between investment into male sexual traits and immune function provide the foundation for some of the most prominent models of sexual selection. Post-copulatory sexual selection on the male ejaculate is intense, and therefore trade-offs should occur between investment into the ejaculate and the immune system. Examples of such trade-offs exist, including that between sperm quality and immunity in the Australian cricket, Teleogryllus oceanicus. Here, we explore the dynamics of this trade-off, examining the effects that increased levels of sexual interaction have on the viability of a male's sperm across time, and the concomitant effects on immune function. Males were assigned to a treatment, whereby they cohabited with females that were sexually immature, sexually mature but incapable of copulation, or sexually mature and capable of copulation. Sperm viability of each male was then assessed at two time points: six and 13 days into the treatment, and immune function at day 13. Sperm viability decreased across the time points, but only for males exposed to treatment classes involving sexually mature females. This decrease was similar in magnitude across both sexually mature classes, indicating that costs to the expression of high sperm viability are incurred largely through levels of pre-copulatory investment. Males exposed to immature females produced sperm of low viability at both time points. Although we confirmed a weak negative association between sperm viability and lytic activity (a measure of immune response to bacterial infection at day 13, this relationship was not altered across the mating treatment. Our results highlight that sperm viability is a labile trait, costly to produce, and subject to strategic allocation in these crickets.

Artocarpus heterophyllus seeds inhibits sexual competence but not fertility of male rats.

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Ratnasooriya, W D; Jayakody, J R A C

2002-03-01

According to Ayurvedic literature of Sri Lanka, roasted seeds of Artocarpus heterophyllus Lam. (Family: Moraceae) has aphrodisiac activity. However, some reproductively active young men in rural areas of Sri Lanka claim that consumption of these seeds few hours prior to coitus disrupts sexual function. Because of these two conflicting claims, it was thought useful to scientifically investigate the effects of A. heterophyllus seeds on male sexual function and fertility. This was done using a seed suspension in 1% methylcellulose (SS) in rats. In a sexual behaviour study using receptive female rats, an oral administration of 500 mg/kg dose of SS markedly inhibited libido, sexual arousal, sexual vigour and sexual performance within 2 hr. Further, the treatment induced a mild erectile dysfunction. These antimasculine effects on sexual function was not evident 6 hr post treatment indicating rapid onset and offset of action. Further, these actions on the sexual behaviour was not due to general toxicity, liver toxicity, stress or reduction in blood testosterone level but due to marked sedative activity. In a mating study, SS failed to alter ejaculating competence and fertility. These results suggest that A. heterophyllous seeds do not have aphrodisiac action, at least, in rats.

Homens adolescentes e vida sexual: heterogeneidades nas motivações que cercam a iniciação sexual Adolescent males and sex life: heterogeneous motivations related to sexual debut

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Ana Luiza Vilela Borges

2007-01-01

Full Text Available Buscou-se descrever a trajetória afetivo-amorosa e razões para o início ou adiamento da vida sexual de adolescentes do sexo masculino, por meio de entrevistas com 184 homens de 15 a 19 anos de idade, residentes no Município de São Paulo, Brasil, em 2002. O início da vida sexual ocorreu, entre outros, por conta da atração física, da curiosidade e do desejo de perder a virgindade, sugerindo um caráter mais próximo do papel social masculino. Por outro lado, a maior parte dos adolescentes virgens justificou sua opção por questões de ordem romântica, como não ter encontrado a pessoa certa ou porque gostaria de casar-se virgem. Os resultados revelaram um duplo padrão social em que há a valorização do sentimento de amor e entrega à pessoa amada simultaneamente à premência física e instintiva para o sexo. Padrões tradicionais de masculinidade, como a dissociação entre sexo e amor, parecem estar sendo transpostos no tocante à iniciação sexual, revelando diversidade nos modos de viver a sexualidade na adolescência que, por sua vez, estão relacionados à saúde sexual e reprodutiva dos homens e suas parcerias.This article describes male adolescents' affective history and reasons for initiating or postponing sexual activity, using interviews with 184 males ages 15 to 19 and residing in the city of São Paulo, Brazil, in 2002. Factors for sexual debut included physical attraction, curiosity, and the desire to lose their virginity, suggesting a profile similar to the male social role. Most of the virgin adolescent males justified their choice based on issues of a romantic order, such as not having found the right person or because they preferred to remain virgin until marrying. The results showed a dual social pattern, valuing the feeling of love and deliverance to the loved one, simultaneously with the pressing physical and instinctive desire for sex. Traditional patterns of masculinity, like the dissociation between sex and

Extra-marital sexual partnerships and male friendships in rural Malawi

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Shelley Clark

2010-01-01

Full Text Available Extra-marital sexual partnerships (EMSPs are a major route of HIV/AIDS transmission in sub-Saharan Africa. In this paper, we investigate the roles of two types of male friendships - best friends and friends with whom they talk about AIDS - in determining whether men have EMSPs. Using data from men in rural Malawi, we find that men's current extra-marital sexual behavior is most closely correlated with their best friends', but that the behaviors of both types of friends are associated with men's subsequent EMSPs. These findings suggest that men's friendships could be used to help combat the AIDS epidemic.

Evaluation of the aphrodisiac activity of Tribulus terrestris Linn. in sexually sluggish male albino rats

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Singh, Surender; Nair, Vinod; Gupta, Yogendra K.

2012-01-01

Objectives: To study the effect of acute and repeated dose administration of lyophilized aqueous extract of the dried fruits of Tribulus terrestris (LAET) on sexual function in sexually sluggish male albino rats. Materials and Methods: Aphrodisiac activity of the test drug was evaluated in terms of exhibited sexual behavior. In order to assess the effect of chronic T. terrestris exposure on the hypothalamus--pituitary--gonadal axis, testosterone level estimation and sperm count were carried out. Twenty-eight-day oral toxicity studies were carried out to evaluate the long-term effects of the LAET administration on different body systems. Results: A dose-dependent improvement in sexual behavior was observed with the LAET treatment as characterized by an increase in mount frequency, intromission frequency, and penile erection index, as well as a decrease in mount latency, intromission latency, and ejaculatory latency. The enhancement of sexual behavior was more prominent on chronic administration of LAET. Chronic administration of LAET produced a significant increase in serum testosterone levels with no significant effect on the sperm count. No overt body system dysfunctions were observed in 28-day oral toxicity study. Conclusions: Findings of the present study validate the traditional use of T. terrestris as a sexual enhancer in the management of sexual dysfunction in males. PMID:22368416

HIV-negative male couples' attitudes about pre-exposure prophylaxis (PrEP) and using PrEP with a sexual agreement.

Science.gov (United States)

Mitchell, Jason W; Lee, Ji-Young; Woodyatt, Cory; Bauermeister, José; Sullivan, Patrick; Stephenson, Rob

2016-08-01

One efficacious strategy to help prevent HIV is oral pre-exposure prophylaxis (PrEP), a daily regimen of antiretroviral treatment taken by HIV-negative individuals. Two of the recommendations of Centers for Disease Control and Prevention (CDC) guidelines for PrEP pertain to being in a relationship (i.e., male couples). Despite the recognition of how primary partners in male couples' relationships shape HIV risk and CDC's PrEP guidelines, there is a paucity of data that examine HIV-negative male couples' attitudes toward PrEP use and using PrEP with a sexual agreement. A sexual agreement is an explicit agreement made between two individuals about what sex and other related behaviors may occur within and outside of their relationship. In this qualitative study, we examine HIV-negative male couples' attitudes toward PrEP use and whether they thought PrEP could be integrated into a sexual agreement. Data for this study are drawn from couple-level interviews conducted in 2014 with 29 HIV-negative male couples who had a sexual agreement and were from Atlanta or Detroit. Both passive (e.g., flyers) and active (e.g., targeted Facebook advertisements) recruitment methods were used; the sample was stratified by agreement type. Thematic analysis was applied to identify the following themes regarding HIV-negative male couples' attitudes toward PrEP use: (1) PrEP and condom use; (2) concerns about PrEP (e.g., effectiveness, side effects, and promoting sexually risky behavior); and (3) accessibility of PrEP. Some thought PrEP could be a part of couples' agreement because it could help reduce sexual anxiety and sexual risk, and would help keep the couple safe. Others described PrEP use with an agreement as something for "others". Some were also concerned that incorporating PrEP could usurp the need for a sexual agreement in a couples' relationship. These themes highlight the need to improve informational messaging and promotion efforts about PrEP among HIV-negative male couples

Differential effects of central injections of D1 and D2 receptor agonists and antagonists on male sexual behavior in Japanese quail.

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Kleitz-Nelson, H K; Cornil, C A; Balthazart, J; Ball, G F

2010-07-01

A key brain site in the control of male sexual behavior is the medial pre-optic area (mPOA) where dopamine stimulates both D1 and D2 receptor subtypes. Research completed to date in Japanese quail has only utilized systemic injections and therefore much is unknown about the specific role played by dopamine in the brain and mPOA in particular. The present study investigated the role of D1 and D2 receptors on male sexual behavior by examining how intracerebroventricular injections and microinjections into the mPOA of D1 and D2 agonists and antagonists influenced appetitive and consummatory aspects of sexual behavior in male quail. Experiments 1 and 2 investigated the effects of intracerebroventricular injections at three doses of D1 or D2 agonists and antagonists. The results indicated that D1 receptors facilitated consummatory male sexual behavior, whereas D2 receptors inhibited both appetitive and consummatory behaviors. Experiment 3 examined the effects of the same compounds specifically injected in the mPOA and showed that, in this region, both receptors stimulated male sexual behaviors. Together, these data indicated that the stimulatory action of dopamine in the mPOA may require a combined activation of D1 and D2 receptors. Finally, the regulation of male sexual behavior by centrally infused dopaminergic compounds in a species lacking an intromittent organ suggested that dopamine action on male sexual behavior does not simply reflect the modulation of genital reflexes due to general arousal, but relates to the central control of sexual motivation. Together, these data support the claim that dopamine specifically regulates male sexual behavior.

Male Sexual Quality Of Life Is Maintained Satisfactorily Throughout Life In The Amazon Rainforest

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Thiago Teixeira, MD, MSc

2018-06-01

Full Text Available Introduction: The Amazon Rainforest is a cradle of biodiversity, where different ethnic groups have specific sexual habits. Aims: To define the average sexual quality of life of Amazonian men 18 to 69 years old, evaluate the influence of aging on their sexual function, and calculate the prevalence of premature ejaculation, delayed ejaculation, and hypoactive sexual desire disorder. Methods: A cross-sectional quantitative probability sample study was performed with a demographically representative population (N = 385, with data collected privately at participants’ houses, including men who had been sexually active for a minimum of 6 months. The Male Sexual Quotient (MSQ was used to measure sexual satisfaction and function. Statistical analysis was performed with SPSS 21.0 using the Kruskal-Wallis test (P < .05, and a multiple linear regression analysis was performed to investigate which factors could predict participants’ quality of sexual life. Main Outcome Measures: MSQ scores. Results: The response rate was 81.69%. The mean age was 36.00 ± 12.95 years, and most men had mixed ethnicity (63.11%, were self-employed (42.07%, had a monthly earned income of US$0 to US$460 (46.75%, and were single (36.10%. The mean MSQ score was 80.39 ± 12.14 (highly satisfied. None of the demographic characteristics showed a statistically significant influence on sexual satisfaction. The difference in quality of sexual life was statistically significant compared with age (P < .01. The domains of desire (P < .01, partner satisfaction (P = .04, and erection quality (P < .01, P = .03, P = .02 were statistically significant. Prevalences of sexual dysfunctions were 36.54% for premature ejaculation, 6.5% for delayed ejaculation, and 11.69% for hypoactive sexual desire disorder. Conclusions: Independent of age, these men have an excellent quality of sexual life. Sexual domains such as desire, partner satisfaction, and erection quality are related to the

Rethinking sexual initiation: pathways to identity formation among gay and bisexual Mexican male youth.

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Carrillo, Héctor; Fontdevila, Jorge

2011-12-01

The topic of same-sex sexual initiation has generally remained understudied in the literature on sexual identity formation among sexual minority youth. This article analyzes the narratives of same-sex sexual initiation provided by 76 gay and bisexual Mexican immigrant men who participated in interviews for the Trayectos Study, an ethnographic study of sexuality and HIV risk. These participants were raised in a variety of locations throughout Mexico, where they also realized their same-sex attraction and initiated their sexual lives with men. We argue that Mexican male same-sex sexuality is characterized by three distinct patterns of sexual initiation--one heavily-based on gender roles, one based on homosociality, and one based on object choice--which inform the men's interpretations regarding sexual roles, partner preferences, and sexual behaviors. We analyzed the social factors and forms of cultural/sexual socialization that lead sexual minority youth specifically to each of these three patterns of sexual initiation. Our findings confirm the importance of studying same-sex sexual initiation as a topic in its own right, particularly as a tool to gain a greater understanding of the diversity of same-sex sexual experiences and sexual identities within and among ethnic/cultural groups.

Bullying, Physical Aggression, Gender-Atypicality, and Sexual Orientation in Samoan Males.

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Semenyna, Scott W; Vasey, Paul L

2017-07-01

Bullying is characterized by the repeated attempts of a group or individual to gain social advantage by the use of relational, verbal, or physical aggression against a target, especially when there is a perceived or actual power imbalance (Espelage & Swearer, 2003). One consistent finding is that gay (i.e., androphilic) males report higher rates of victimization due to bullying in adolescence than their heterosexual (i.e., gynephilic) counterparts. Western data indicate that gender-atypical behavior, regardless of sexual orientation, is a key predictor of victimization due to bullying. Androphilic males generally display childhood gender-atypicality, including reduced levels of physical aggression, which may cause bullies to perceive them as "easy" targets. In order to test the associations between sexual orientation, childhood gender-atypicality, and recalled victimization due to bullying, a sample of Samoan gynephilic men (n = 100) were compared to a group of Samoan transgender androphilic males (n = 103), known as fa'afafine. Although the fa'afafine reported far more childhood gender-atypicality, the two groups did not differ significantly on measures of physical aggression or their reported rates of victimization due to bullying. Additionally, greater physical aggression, not gender-atypicality, was the only significant predictor of being bullied in both men and fa'afafine. These results suggest that there is nothing inherent in sexual orientation or childhood gender-atypicality that would potentiate victimization from bullying. Instead, the cultural context in which a bully functions influences the extent to which these are "acceptable" reasons to target certain individuals.

Polymorphic variants of neurotransmitter receptor genes may affect sexual function in aging males: data from the HALS study.

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Jóźków, Paweł; Słowińska-Lisowska, Małgorzata; Łaczmański, Łukasz; Mędraś, Marek

2013-01-01

Human behavior is influenced by a number of brain neurotransmitters. Central dopamine, serotonin and melanocortin systems have special importance for male sexual function. We searched for associations between male aging symptoms and polymorphic sites of serotonin (5-HTR1B), melanocortin (MC4R) and dopamine (DRD2, DRD4) receptors. In a population-based sample, genotyping of 5-HTR1B (polymorphism: G861C), MC4R (polymorphisms: C-2745T, Val103Ile), DRD2 (polymorphism: C313T) and DRD4 (polymorphism: 48-bp VNTR) was performed in 387 healthy men. The Aging Males' Symptoms (AMS) scale was used to evaluate specific ailments of aging men. We analyzed answers to questions from the AMS scale. Five points of the questionnaire addressed sexual symptoms of the aging male: feeling of passing one's peak, decrease in beard growth, decrease in ability/frequency to perform sexually, decrease in the number of morning erections, and decrease in sexual desire/libido (lacking pleasure in sex, lacking desire for sexual intercourse). Relations between reported symptoms and variants of the polymorphic sites of the studied genes were assessed. After adjusting for confounding factors (education, arterial hypertension, physical activity, weight, waist circumference) an association between the sexual dimension of AMS and genetic variants of 5-HTR1B G861C (p = 0.04) was observed. Variability of neurotransmitter receptor genes may be associated with sexual symptoms of aging in men. Copyright © 2013 S. Karger AG, Basel.

The Internet's Multiple Roles in Facilitating the Sexual Orientation Identity Development of Gay and Bisexual Male Adolescents.

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Harper, Gary W; Serrano, Pedro A; Bruce, Douglas; Bauermeister, Jose A

2016-09-01

One emerging avenue for the exploration of adolescents' sexual orientation identity development is the Internet, since it allows for varying degrees of anonymity and exploration. The purpose of this phenomenological study was to examine the role of the Internet in facilitating the sexual orientation identity development process of gay and bisexual male adolescents. Qualitative interviews were conducted with an ethnically diverse sample of 63 gay/bisexual male adolescents (ages 15-23). Participants reported using a range of Internet applications as they explored and came to accept their sexual orientation identity, with the intended purpose and degree of anonymity desired determining which applications were used. Youth reported that the Internet provided a range of functions with regard to the exploration and acceptance of their sexual orientation identity, including (1) increasing self-awareness of sexual orientation identity, (2) learning about gay/bisexual community life, (3) communicating with other gay/bisexual people, (4) meeting other gay/bisexual people, (5) finding comfort and acceptance with sexual orientation, and (6) facilitating the coming out process. Future research and practice may explore the Internet as a platform for promoting the healthy development of gay and bisexual male adolescents by providing a developmentally and culturally appropriate venue for the exploration and subsequent commitment to an integrated sexual orientation identity. © The Author(s) 2015.

Sexual violence and the risk of HIV transmission in sexual partners of male injecting drug users in Tien Du district, Bac Ninh province of Vietnam.

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Do, Vinh Thi; Ho, Hien Thi; Nguyen, Tri Manh; Do, Huynh Khac

2018-04-01

We conducted a cross-sectional study among 148 women who were regular sexual partners of male injecting drug users in Tien Du, Bac Ninh province, Vietnam to identify the rate of HIV infection and factors associated with HIV transmission among them. HIV infection rate among sexual partners was high, 11.5%. Sexual violence was prevalent, 63.5% among sexual partners; 94.1% (16/17) among those with HIV. We discovered an association between sexual violence and HIV infection. Sexual partners suffering from sexual violence caused by their regular sexual partners faced 9.24 times higher HIV risk than those who did not have sexual violence.

Hormonal causes of male sexual dysfunctions and their management (hyperprolactinemia, thyroid disorders, GH disorders, and DHEA).

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Maggi, Mario; Buvat, Jaques; Corona, Giovanni; Guay, André; Torres, Luiz Otavio

2013-03-01

Besides hypogonadism, other endocrine disorders have been associated with male sexual dysfunction (MSD). To review the role of the pituitary hormone prolactin (PRL), growth hormone (GH), thyroid hormones, and adrenal androgens in MSD. A systematic search of published evidence was performed using Medline (1969 to September 2011). Oxford Centre for Evidence-Based Medicine-Levels of Evidence (March 2009) was applied when possible. The most important evidence regarding the role played by PRL, GH, thyroid, and adrenal hormone was reviewed and discussed. Only severe hyperprolactinemia (>35 ng/mL or 735 mU/L), often related to a pituitary tumor, has a negative impact on sexual function, impairing sexual desire, testosterone production, and, through the latter, erectile function due to a dual effect: mass effect and PRL-induced suppression on gonadotropin secretion. The latter is PRL-level dependent. Emerging evidence indicates that hyperthyroidism is associated with an increased risk of premature ejaculation and might also be associated with erectile dysfunction (ED), whereas hypothyroidism mainly affects sexual desire and impairs the ejaculatory reflex. However, the real incidence of thyroid dysfunction in subjects with sexual problems needs to be evaluated. Prevalence of ED and decreased libido increase in acromegalic patients; however, it is still a matter of debate whether GH excess (acromegaly) may create effects due to a direct overproduction of GH/insulin-like growth factor 1 or because of the pituitary mass effects on gonadotropic cells, resulting in hypogonadism. Finally, although dehydroepiandrosterone (DHEA) and its sulfate have been implicated in a broad range of biological derangements, controlled trials have shown that DHEA administration is not useful for improving male sexual function. While the association between hyperprolactinemia and hypoactive sexual desire is well defined, more studies are needed to completely understand the role of other hormones in

Relational and sexual fluidity in females partnered with male-to-female transsexual persons.

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Aramburu Alegría, C

2013-03-01

This paper reports on a study examining sexuality in females who remain partnered with male-to-female transsexual persons. Participants' self-view and sexual fluidity following their partners' transition from man to woman is examined. Sixteen females participated in in-depth, semi-structured interviews. An inductive process of data analysis was conducted, using the constant comparative method, an iterative process by which data are compared within and across subjects. Data were collected until thematic saturation was achieved. Four themes related to sexuality emerged: (1) questioning of sexual orientation; (2) sexual orientation categorization; (3) relational fluidity without sexual relations; and (4) relational fluidity with sexual relations. Participants maintained a heterosexual identity, yet modified their self-view to include an identity that reflected their reformed relationship. The majority of the respondents reported sexual lives that were active or evolving. Others remained in relationships that no longer included sexual activity. The study findings highlight the potential fluidity within the sexual and relational lives of females, and can enhance healthcare providers' preparedness and efficacy with diverse populations. Providers are in a unique position to offer resources to patients who identify as sexually or gender-diverse, or who are in relationships with sexually or gender-diverse persons. © 2012 Blackwell Publishing.

Age- and tactic-related paternity success in male African elephants

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Rasmussen, Henrik Barner; Okello, J. B. A.; Wittemyer, G.

2008-01-01

on age- and tactic-specific paternity success in male African elephants are the first from a free-ranging population and demonstrate that paternity success increases dramatically with age, with the small number of older bulls in the competitive state of musth being the most successful sires. However......, nonmusth males sired 20% of genotyped calves, and 60% of mature bulls (>20 years old) were estimated to have sired offspring during the 5-year study period. The 3 most successful males sired less than 20% of the genotyped offspring. Hence, contrary to prediction from behavior and life-history traits......, reproduction was not heavily skewed compared with many other mammalian systems with a similar breeding system. Nevertheless, these results indicate that trophy hunting and ivory poaching, both of which target older bulls, may have substantial behavioral and genetic effects on elephant populations. In addition...

To fight or mate? Hormonal control of sex recognition, male sexual behavior and aggression in the gecko lizard.

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Schořálková, Tereza; Kratochvíl, Lukáš; Kubička, Lukáš

2018-01-01

Squamate reptiles are a highly diversified vertebrate group with extensive variability in social behavior and sexual dimorphism. However, hormonal control of these traits has not previously been investigated in sufficient depth in many squamate lineages. Here, we studied the hormonal control of male sexual behavior, aggressiveness, copulatory organ (hemipenis) size and sex recognition in the gecko Paroedura picta, comparing ovariectomized females, ovariectomized females treated with exogenous dihydrotestosterone (DHT), ovariectomized females treated with exogenous testosterone (T), control females and males. The administration of both T and DHT led to the expression of male-typical sexual behavior in females. However, in contrast to T, increased circulating levels of DHT alone were not enough to initiate the full expression of male-typical offensive aggressive behavior and development of hemipenes in females. Ovariectomized females were as sexually attractive as control females, which does not support the need for the demasculinization of the cues used for sex recognition by ovarian hormones as suggested in other sauropsids. On the other hand, our results point to the masculinization of the sex recognition cues by male gonadal androgens. Previously, we also demonstrated that sexually dimorphic growth is controlled by ovarian hormones in P. picta. Overall, it appears that individual behavioral and morphological sexually-dimorphic traits are controlled by multiple endogenous pathways in this species. Variability in the endogenous control of particular traits could have permitted their disentangling during evolution and the occurrence of (semi)independent changes across squamate phylogeny. Copyright © 2017 Elsevier Inc. All rights reserved.

THE SEXUAL JURIDIFICATION AND THE SIMBOLIC VIOLENCE: A SOCIAL AND LEGAL ANALYSIS FROM THE MALE DOMINATION THEORY OF PIERRE BOURDIEU

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Barbara Lou da Costa Veloso Dias

2015-12-01

Full Text Available This article has as his main object of study the juridification process of sexuality and its relationship with the male symbolic violence. Therefore, initially it was made explanations about sexuality juridification process, with the illustration of that process by analyzing three bills; followed by exposure of the main aspects of the Pierre Bourdieu's theory of male domination, especially the concepts of Symbolic Domination, Symbolic Power, Symbolic Violence and Habitus; highlighting, at a later time, the incorporation of that domination by subversive movements; to the end, analyze a possible relationship between the quoted sexuality juridification process and symbolic violence, in accordance with the wisdom of Pierre Bourdieu. The objectives are, initially, conceptualize and illustrate the sexuality of juridification process; expose the main elements of the Male Domination's theory written by Pierre Bourdieu; examine the idea of incorporation of domination from the theoretical background discussed in the previous section; and to investigate the relationship between that sexuality juridification process and the male symbolic violence. These objectives have the purpose of analyze the hypothesis of this present article, which consists of the view that the jurification of sexuality process incorporates a male symbolic violence, even this having a subversive nature.

Sexual Health Risk Behavior Disparities Among Male and Female Adolescents Using Identity and Behavior Indicators of Sexual Orientation.

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Paul Poteat, V; Russell, Stephen T; Dewaele, Alexis

2017-12-04

Sexual minority adolescent sexual risk behavior studies often overlook young women, do not consider behavior- and identity-based sexual orientation indicators in combination, and focus mainly on condomless sex. We examined multiple risk behaviors in a large sample of adolescent young men and women using combined behavior- and identity-based indices. The 2015 Dane County Youth Assessment data included 4734 students in 22 high schools who had ever voluntarily engaged in sexual contact (51.7% male; 76.0% White, non-Hispanic). Items assessed having sex with unfamiliar partners, sex while using substances, using protection, and STI testing. Logistic regressions tested for disparities based on combined identity- and behavior-based sexual orientation indicators. For both young men and women, youth who reported heterosexual or questioning identities-but who had sex with same-sex partners-were at consistently greater risk than heterosexual youth with only different-sex partners. Also, for both young men and women, bisexuals with partners of both sexes more consistently reported higher risk than heterosexual youth than did bisexuals with only different-sex partners. Risk behavior for gay young men who had sex only with men mirrored those in extant literature. Risk levels differed for specific groups of sexual minority young women, thus deserving further attention. Findings underscore the need for sexual health research to consider sexual orientation in a more multidimensional manner.

Rapid decreases in preoptic aromatase activity and brain monoamine concentrations after engaging in male sexual behavior.

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Cornil, C A; Dalla, C; Papadopoulou-Daifoti, Z; Baillien, M; Dejace, C; Ball, G F; Balthazart, J

2005-09-01

In Japanese quail, as in rats, the expression of male sexual behavior over relatively long time periods (days to weeks) is dependent on the local production of estradiol in the preoptic area via the aromatization of testosterone. On a short-term basis (minutes to hours), central actions of dopamine as well as locally produced estrogens modulate behavioral expression. In rats, a view of and sexual interaction with a female increase dopamine release in the preoptic area. In quail, in vitro brain aromatase activity (AA) is rapidly modulated by calcium-dependent phosphorylations that are likely to occur in vivo as a result of changes in neurotransmitter activity. Furthermore, an acute estradiol injection rapidly stimulates copulation in quail, whereas a single injection of the aromatase inhibitor vorozole rapidly inhibits this behavior. We hypothesized that brain aromatase and dopaminergic activities are regulated in quail in association with the expression of male sexual behavior. Visual access as well as sexual interactions with a female produced a significant decrease in brain AA, which was maximal after 5 min. This expression of sexual behavior also resulted in a significant decrease in dopaminergic as well as serotonergic activity after 1 min, which returned to basal levels after 5 min. These results demonstrate for the first time that AA is rapidly modulated in vivo in parallel with changes in dopamine activity. Sexual interactions with the female decreased aromatase and dopamine activities. These data challenge established views about the causal relationships among dopamine, estrogen action, and male sexual behavior.

Is there an inhibitory role of cortisol in the mechanism of male sexual arousal and penile erection?

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Uckert, Stefan; Fuhlenriede, Mark H; Becker, Armin J; Stief, Christian G; Scheller, Friedemann; Knapp, Wolfram H; Jonas, Udo

2003-12-01

It has been speculated for more than 2 decades whether there is a significance of adrenal corticosteroids, such as cortisol, in the process of normal male sexual function, especially in the control of sexual arousal and the penile erectile tissue. However, only few in vivo studies have been carried out up until now on the effects of cortisol on human male sexual performance and penile erection. In order to evaluate further the role of cortisol in male sexual activity, the present study was conducted to detect serum levels of cortisol in the systemic and cavernous blood taken during different penile conditions from healthy males. The effects of cortisol derivative prednisolone, catecholamine norepinephrine (NE) and the peptide endothelin-1 (ET-1) on isolated human corpus cavernosum (HCC) were investigated using the organ bath technique. Fifty-four healthy adult male subjects were exposed to erotic stimuli in order to elicit penile tumescence and rigidity. Whole blood was simultaneously aspirated from the corpus cavernosum and the cubital vein during different penile conditions. Serum levels of cortisol (microg/dl) were determined by means of a radioimmunoassay (ELISA). In the healthy volunteers, cortisol serum levels significantly decreased in the systemic circulation and the cavernous blood with increasing sexual arousal, when the flaccid penis became rigid. During detumescence, the mean cortisol level remained unaltered in the systemic circulation, whereas in the cavernous compartment, it was found to decrease further. Under all penile conditions, no significant differences were registered between cortisol levels in the systemic circulation and in the cavernous blood. Cumulative addition of NE and ET-1 (0.001-10 microM) induced contraction of isolated HCC strips, whereas the contractile response to prednisolone was negligible. Our results strongly suggest an inhibitory role for cortisol in the mechanism of male sexual response and behaviour. These properties are

Sexual behavior experiences and characteristics of male-female partnerships among HIV positive adolescent girls and young women: Qualitative findings from Zimbabwe.

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Mavhu, Webster; Rowley, Elizabeth; Thior, Ibou; Kruse-Levy, Natalie; Mugurungi, Owen; Ncube, Getrude; Leclerc-Madlala, Suzanne

2018-01-01

New HIV infections among sub-Saharan Africa's adolescent girls and young women (AGYW, ages 15-24) greatly exceed those of their male peers. In addition, AGYW tend to acquire HIV at a much earlier age. Understanding the factors associated with HIV infection in AGYW could inform effective prevention and treatment interventions for these populations and their male sexual partners. This qualitative study, conducted October-November 2016, was a follow on to a quantitative survey that sought to characterize male sexual partners and sexual behaviors of sexually active HIV positive AGYW in Zimbabwe. The qualitative study explored sexual behavior experiences and characteristics of male-female partnerships among the same participants. We conducted in-depth interviews with purposively sampled AGYW (16-24 years). Audio recorded qualitative data were transcribed, translated into English, and thematically coded using NVivo. 28 AGYW (n = 14 urban, n = 14 rural) took part in the in-depth interviews. 50% were 16-19 years old. Discussions with 10/11 (91%) AGYW who were reportedly infected through sex suggested that they had acquired HIV from their husbands or romantic partners. Accounts also suggested that the age difference between respondents and their male sexual partners was ≥5 years. Overall, respondents described two types of male partners: those older (''sugar daddies'', men ≥35 years old) and younger (characteristics of relationships between AGYW and their male sexual partners. Findings could inform interventions to engender risk perception among AGYW, promote female-controlled HIV prevention efforts and, foster risk-reduction among men.

Sexual selection and hermaphroditic organisms: Testing theory

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Janet L. LEONARD

2013-08-01

Full Text Available Sexual selection is widespread if not ubiquitous in hermaphroditic organisms. Although many phenomena that have been described as sexual selection in gonochores, (e.g. harem polygamy, multiple mating, elaborate courtship, even secondary sexual characters can be found in some hermaphrodites, what is more interesting is the ways in which sexual selection in hermaphrodites may differ from dioecious taxa. In hermaphrodites, an individual’s mating success includes its success from both sexual roles. Secondly, in many simultaneously hermaphroditic taxa there is strong evidence of sexual selection and yet the ope­rational sex ratio is 1:1, by definition. Many simultaneous hermaphrodites have elaborate courtship and genital anatomy, suggesting sexual selection plays an important role in reproductive success. Sperm competition and cryptic female choice mean that the number of mates acquired is not necessarily a predictor of reproductive success. Even in simultaneous hermaphrodites with reciprocal mating, variance in reproductive success through the male role and through the female role may differ in a population. Moreover hermaphrodites may choose to emphasize one sexual role over the other. Data suggest that the preferred role varies in hermaphrodites, which creates an opportunity to test fundamental predictions and assumptions of sexual selection theory. Hermaphrodites may vary their emphasis on one sexual role over the other either developmentally or behaviorally in response to environmental or social parameters. How they use this capability in acquiring more or higher quality mates still requires study [Current Zoology 59 (4: 579–588, 2013].

Effect of Mucuna pruriens (Linn.) on sexual behavior and sperm parameters in streptozotocin-induced diabetic male rat.

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Suresh, Sekar; Prakash, Seppan

2012-12-01

Sexual dysfunction is one of the major secondary complications in the diabetic. Mucuna pruriens, a leguminous plant identified for its antidiabetic, aphrodisiac, and improving fertility properties, has been the choice of Indian traditional medicine. Objective of the present study was to analyze the efficacy of M. pruriens on male sexual behavior and sperm parameters in long-term hyperglycemic male rats. Male albino rats were divided as group I control, group II diabetes induced (streptozotocin [STZ] 60 mg/kg of body weight (b.w.) in 0.1 M citrate buffer), group III diabetic rats administered with 200 mg/kg b.w. of ethanolic extract of M. pruriens seed, group IV diabetic rats administered with 5 mg/kg b.w. of sildenafil citrate (SC), group V administered with 200 mg/kg b.w. of extract, and group VI administered with 5 mg/kg b.w. of SC. M. pruriens and SC were administered in single oral dosage per day for a period of 60 days. The animals were subjected to mating behavior analyses, libido, test of potency, and epididymal sperms were analyzed. The mating behavior, libido, test of potency, along with epididymal sperms were studied. The study showed significant reduction in sexual behavior and sperm parameters in group II. Daily sperm production (DSP) and levels of follicular stimulating hormone, luteinizing hormone, and testosterone were significantly reduced in group II, whereas the animals with diabetes administered with seed extract of M. pruriens (group III) showed significant improvement in sexual behavior, libido and potency, sperm parameters, DSP, and hormonal levels when compared to group II. The present work reveals the potential efficacy of ethanolic seed extract of M. pruriens to improve male sexual behavior with androgenic and antidiabetic effects in the STZ-induced diabetic male rats. This study supports the usage of M. pruriens in the Indian system of medicine as sexual invigorator in diabetic condition and encourages performing similar study in men. �

"STEMulating" success factors: An investigation of the academic talents of successful Black male college graduates from STEM programs

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Hendricks, Jill T.

This phenomenological research study explored the contributing factors experienced by Black males that epitomized their academic success in a STEM (Science, Technology, Engineering, and Mathematics) area of study. During this investigative project, eleven Black male students were interviewed to determine how they were able to successfully navigate and complete a STEM degree. The data was collected through a qualitative inquiry, which involved interviewing students and collecting the data and organizing their perspectives into common themes. The principal findings in this study suggest that Black males can excel when primary influential people establish high expectations and believe and encourage Black males to succeed by providing the essential educational support models requisite to warrant success; the Black male maintains and affirms a self-assured self-worth in himself; the Black male is exposed to these fields and professions early on in their educational quest to enable them to witness first hand powerful and productive opportunities and pathways to academic success; exposure to other Black successful male role models who can mentor and show positive proof that with effort, these fields can become a reality; increase in academic motivation and recommendations from educators and counselors who direct and guide students into and away from these rigorous career fields. An analysis of the students' individual stories gave a revealing look into the pathways of their consciousness, emotional growth, and perspectives about being a successful STEM major. This kind of insight can be a constructive diagnostic tool for students, educators, counselors, and administrators who want to motivate and influence future students to major in STEM fields of study.

The ontogeny of sexual size dimorphism of a moth: when do males and females grow apart?

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R Craig Stillwell

Full Text Available Sexual dimorphism in body size (sexual size dimorphism is common in many species. The sources of selection that generate the independent evolution of adult male and female size have been investigated extensively by evolutionary biologists, but how and when females and males grow apart during ontogeny is poorly understood. Here we use the hawkmoth, Manduca sexta, to examine when sexual size dimorphism arises by measuring body mass every day during development. We further investigated whether environmental variables influence the ontogeny of sexual size dimorphism by raising moths on three different diet qualities (poor, medium and high. We found that size dimorphism arose during early larval development on the highest quality food treatment but it arose late in larval development when raised on the medium quality food. This female-biased dimorphism (females larger increased substantially from the pupal-to-adult stage in both treatments, a pattern that appears to be common in Lepidopterans. Although dimorphism appeared in a few stages when individuals were raised on the poorest quality diet, it did not persist such that male and female adults were the same size. This demonstrates that the environmental conditions that insects are raised in can affect the growth trajectories of males and females differently and thus when dimorphism arises or disappears during development. We conclude that the development of sexual size dimorphism in M. sexta occurs during larval development and continues to accumulate during the pupal/adult stages, and that environmental variables such as diet quality can influence patterns of dimorphism in adults.

Between contradictions and risks: Mexican male adolescents’ views about teenage pregnancy and its association with sexual behavior.

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Jorge Quiroz

2014-03-01

Full Text Available Objective. To explore the opinions of Mexican male adolescents regarding teenage pregnancy and analyze its association with sexual behavior. Materials and methods. This is a cross-sectional study using a self-administered questionnaire among a conventional sample of male students (15-19 years old in eight public schools in Morelos and Mexico City. Analyses include multivariate models to identify the association between opinions and sexual behaviors. Results. Overall, 68% agree that a teenage pregnancy is a negative event. In a hypothetical case, if a girlfriend got pregnant in this moment 56% would continue in the school whereas 18% would definitely abandon it. Those who affirm that a teenage pregnancy is something very bad have greater odds of using condoms (OR=1.8; p menor que 0.05. Conclusions. Male adolescents’ views about teenage pregnancy are associated with some sexual behaviors; however their opinions reflect several contradictions. The design of surveys directed exclusively to explore male adolescents’ opinions about reproductive health is urgent.

Is perceived parental monitoring associated with sexual risk behaviors of young Black males?

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Richard Crosby

2015-01-01

Full Text Available This study determined whether perceived parental monitoring is associated with any of twelve selected outcomes related to sexual risk behaviors of young Black males. Recruitment occurred in clinics diagnosing and treating sexually transmitted infections. Young Black males living with a parent or guardian (N = 324 were administered a 9-item scale assessing level of perceived parental monitoring. The obtained range was 10–45, with higher scores representing more frequent monitoring. The mean was 29.3 (sd = 7.0. Eight of the twelve outcomes had significant associations with perceived parental monitoring (all in a direction indicating a protective effect. Of these eight, five retained significance in age-adjusted models were ever causing a pregnancy, discussing pregnancy prevention, safer sex, and condom use with sex partners, and using a condom during the last act of penile–vaginal sex. Monitoring by a parent figure may be partly protective against conceiving a pregnancy for Black males 15–23 years of age.

Effects of velvet antler polypeptide on sexual behavior and testosterone synthesis in aging male mice.

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Zang, Zhi-Jun; Tang, Hong-Feng; Tuo, Ying; Xing, Wei-Jie; Ji, Su-Yun; Gao, Yong; Deng, Chun-Hua

2016-01-01

Twenty-four-month-old male C57BL/6 mice with low serum testosterone levels were used as a late-onset hypogonadism (LOH) animal model for examining the effects of velvet antler polypeptide (VAP) on sexual function and testosterone synthesis. These mice received VAP for 5 consecutive weeks by daily gavage at doses of 100, 200, or 300 mg kg-1 body weight per day (n = 10 mice per dose). Control animals (n = 10) received the same weight-based volume of vehicle. Sexual behavior and testosterone levels in serum and interstitial tissue of testis were measured after the last administration of VAP. Furthermore, to investigate the mechanisms of how VAP affects sexual behavior and testosterone synthesis in vivo, the expression of steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), and 3β-hydroxysteroid dehydrogenase (3β-HSD) in Leydig cells was also measured by immunofluorescence staining and quantitative real-time PCR. As a result, VAP produced a significant improvement in the sexual function of these aging male mice. Serum testosterone level and intratesticular testosterone (ITT) concentration also increased in the VAP-treated groups. The expression of StAR, P450scc, and 3β-HSD was also found to be enhanced in the VAP-treated groups compared with the control group. Our results suggested that VAP was effective in improving sexual function in aging male mice. The effect of velvet antler on sexual function was due to the increased expression of several rate-limiting enzymes of testosterone synthesis (StAR, P450scc, and 3β-HSD) and the following promotion of testosterone synthesis in vivo.

Risky sexual behaviors and associated factors among male and female students in Jimma Zone preparatory schools, South West Ethiopia: comparative study.

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Fentahun, Netsanet; Mamo, Abebe

2014-01-01

Youth engage in risk sexual behavior due to insufficient knowledge of reproductive health and family planning. Youth sexual behavior is important not only because of the possible reproductive outcomes, but also because of sexually transmitted infections. The level of risks and sexual behaviors are different between male and female youth due to sexual exposure and socio-cultural factors. The aim of this study was to compare risky sexual behaviors and associated factors among male and female preparatory school (grades 11 and 12) students in Jimma Zone. A comparative cross-sectional study was conducted in 5 randomly selected preparatory schools of Jimma Zone. A total of 520 students were selected using simple random sampling technique. A structured, pretested and self-administered questionnaire was used to collect data. Both descriptive analysis and binary logistic regressions were performed on the data to understand risky sexual behaviors among students. Twenty-two (25.9%) of male and 25(21.6%) of female students had two or more sexual partners in the last six months. Eighty-three (32.3%), 113(43.5%) male and female students were sexually at risk in the last six months. Only 8(9.4%) of the male and 10(8.6%) of the female students used condom consistently in the last six months. Female students living away from their parents were 3 times more likely to be at risk than students living with their parents (OR 95%CI 3.0(1.48-6.34)). Female students who consumed alcohol were 7 times more likely to be at risk than those who did not consume alcohol (OR 95%CI 7.27(3.36-15.7)). Male students who consumed alcohol were 2.8 times more likely to be at risk than those who did not consumed alcohol (OR 95%CI, 2.81(1.3-6.06)). Male students who chewed khat were 4.6 times more likely to be at risk than students who did not chew khat (OR 95%CI, 4.58(1.95-10.76). Living arrangement, educational status of parents, family connectedness, alcohol consumption and khat-chewing were the major

[Protein content in urine of male and female water vole (Arvicola amphibious) at the period of spring growth and sexual maturation].

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Nazarova, G G; Proskurniak, L P

2012-01-01

The study was carried out on the captive bread water voles Arvicola amphibious kept in vivarium. At the first decade of January, March, and June, the body length and anogenital distance were measured, the body mass was determined, and urine was collected for determination of its protein content. The obtained results have shown that the protein content depends on sex of the animals and is connected with the reproductive status of males and their dimension-weight characteristics. The urinary protein excretion level in females remained stable at different months, whereas in males its sharp rise was noted at the period of spring growth and sexual maturation. The significant sexual differences were established in March and enhanced in June. In March the urine protein content in males was noted to correlate positively with the body mass and length and with the anogenital distance. The males reached sexual maturity at the earlier calendar terms than the females did; in sexually mature males the urine protein content was significantly higher than in the sexually immature ones.

Evaluations of sexual assault: perceptions of guilt and legal elements for male and female aggressors using various coercive strategies.

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Russell, Brenda L; Oswald, Debra L; Kraus, Shane W

2011-01-01

This study examines the extent to which verdict, guilt, and legal components associated with jury instructions of sexual assault differ as a function of aggressor gender, participant gender, and sexual strategy used (consensual, verbal coercion, alcohol, or physical aggression) to obtain sex. Participants (N = 423; 276 women and 147 men) read a vignette depicting either a couple having consensual sex (control), or a male or female aggressor who initiates sexual intercourse via verbal coercion, use of alcohol, or physical abuse. College students were provided with legal instructions of sexual assault then asked to provide a verdict, degree of guilt, and legal components. Female participants rated guilt and coercion higher than did male participants. Ratings of guilt were highest in the physical assault condition followed by the alcohol, verbal, and control conditions. Female aggressors were rated less guilty than male aggressors. Results are explained in relation to sexual scripts and legal decision making. Lack of significance in verdict decisions and interaction effects suggests male and female aggressors are evaluated similarly using coercive strategies; yet, consent for sex was assumed and attributions of guilt was lower when the aggressor was female. Implications for jury instructions and future research are discussed.

Characterization of a novel bile alcohol sulfate released by sexually mature male sea lamprey (Petromyzon marinus.

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Ke Li

Full Text Available A sulphate-conjugated bile alcohol, 3,12-diketo-4,6-petromyzonene-24-sulfate (DKPES, was identified using bioassay-guided fractionation from water conditioned with sexually mature male sea lamprey (Petromyzon marinus. The structure and relative stereochemistry of DKPES was established using spectroscopic data. The electro-olfactogram (EOG response threshold of DKPES was 10(-7 Molar (M and that of 3-keto petromyzonol sulfate (3 KPZS; a known component of the male sea lamprey sex pheromone was 10(-10 M. Behavioural studies indicated that DKPES can be detected at low concentrations by attracting sexually mature females to nests when combined with 3 KPZS. Nests baited with a mixture of DKPES and 3 KPZS (ratio 1∶29.8 attracted equal numbers of sexually mature females compared to an adjacent nest baited with 3 KPZS alone. When DKPES and 3 KPZS mixtures were applied at ratios of 2∶29.8 and 10∶29.8, the proportion of sexually mature females that entered baited nests increased to 73% and 70%, respectively. None of the sexually mature females released were attracted to nests baited with DKPES alone. These results indicated that DKPES is a component of the sex pheromone released by sexually mature male sea lamprey, and is the second biologically active compound identified from this pheromone. DKPES represents the first example that a minor component of a vertebrate pheromone can be combined with a major component to elicit critical sexual behaviors. DKPES holds considerable promise for increasing the effectiveness of pheromone-baited trapping as a means of sea lamprey control in the Laurentian Great Lakes.

Rapid steroid influences on visually guided sexual behavior in male goldfish

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Lord, Louis-David; Bond, Julia; Thompson, Richmond R.

2013-01-01

The ability of steroid hormones to rapidly influence cell physiology through nongenomic mechanisms raises the possibility that these molecules may play a role in the dynamic regulation of social behavior, particularly in species in which social stimuli can rapidly influence circulating steroid levels. We therefore tested if testosterone (T), which increases in male goldfish in response to sexual stimuli, can rapidly influence approach responses towards females. Injections of T stimulated approach responses towards the visual cues of females 30–45 min after the injection but did not stimulate approach responses towards stimulus males or affect general activity, indicating that the effect is stimulus-specific and not a secondary consequence of increased arousal. Estradiol produced the same effect 30–45 min and even 10–25 min after administration, and treatment with the aromatase inhibitor fadrozole blocked exogenous T’s behavioral effect, indicating that T’s rapid stimulation of visual approach responses depends on aromatization. We suggest that T surges induced by sexual stimuli, including preovulatory pheromones, rapidly prime males to mate by increasing sensitivity within visual pathways that guide approach responses towards females and/or by increasing the motivation to approach potential mates through actions within traditional limbic circuits. PMID:19751737

Organizational effects of diethylstilbestrol on brain vasotocin and sexual behavior in male quail.

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Viglietti-Panzica, Carla; Montoncello, Barbara; Mura, Elena; Pessatti, Marzia; Panzica, GianCarlo

2005-04-15

In Japanese quail, we previously described a sexual dimorphism of the parvocellular vasotocin system of the limbic region that, as the reproductive behavior, is steroid-sensitive and is organized during embryonic life by the exposure to estradiol. We verified in this study whether diethylstilbestrol, a chemical xenoestrogen, has analogous organizational effects on the vasotocin system of limbic regions and on copulatory behavior of male Japanese quail. We injected in the yolk sac of 3 day-old quail embryos diethylstilbestrol or estradiol benzoate (a treatment which suppresses male copulatory behavior in adulthood and reduces vasotocin innervation), or sesame oil (control). No further hormonal manipulations were performed after hatching. Sexual behavior was recorded in males at the age of 6 weeks. Estradiol- and diethylstilbestrol-treated males exhibited a total suppression of copulatory behavior. After behavioral tests, all males were sacrificed and brain sections processed for vasotocin immunocytochemistry. Significant decrease in the density of vasotocin immunoreactivity was detected in the medial preoptic nucleus, in the bed nucleus of stria terminalis, and in the lateral septum of diethylstilbestrol-treated males. The magnocellular vasotocin neurons were, in contrast, not affected. In conclusion, the present data demonstrate that embryonic treatment with diethylstilbestrol induces a full sex reversal of behavioral phenotype as well as a significant decrease of vasotocin expression in the preoptic-limbic region in male Japanese quail. Therefore, the parvocellular vasotocin system could represent an optimal model to investigate the effects of pollutants on neural circuits controlling reproductive functions.

How to be an attractive male: floral dimorphism and attractiveness to pollinators in a dioecious plant

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Waelti Marc O

2009-08-01

Full Text Available Abstract Background Sexual selection theory predicts that males are limited in their reproductive success by access to mates, whereas females are more limited by resources. In animal-pollinated plants, attraction of pollinators and successful pollination is crucial for reproductive success. In dioecious plant species, males should thus be selected to increase their attractiveness to pollinators by investing more than females in floral traits that enhance pollinator visitation. We tested the prediction of higher attractiveness of male flowers in the dioecious, moth-pollinated herb Silene latifolia, by investigating floral signals (floral display and fragrance and conducting behavioral experiments with the pollinator-moth, Hadena bicruris. Results As found in previous studies, male plants produced more but smaller flowers. Male flowers, however, emitted significantly larger amounts of scent than female flowers, especially of the pollinator-attracting compounds. In behavioral tests we showed that naïve pollinator-moths preferred male over female flowers, but this preference was only significant for male moths. Conclusion Our data suggest the evolution of dimorphic floral signals is shaped by sexual selection and pollinator preferences, causing sexual conflict in both plants and pollinators.

Breakfast of champions or kiss of death? Survival and sexual performance of protein-fed, sterile Mediterranean fruit flies (Diptera: Tephritidae)

International Nuclear Information System (INIS)

Yuval, B.; Maor, M.; Levy, K.; Kaspi, R.; Taylor, P.; Shelly, T.

2007-01-01

The sterile insect technique (SIT) is increasingly being used around the world to control Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), the Mediterranean fruit fly as part of an area-wide integrated approach. One option that may improve the effectiveness of the SIT, by increasing the sexual competitiveness of released sterile males, consists of feeding males protein during the post-teneral stage, a diet that increases sexual performance of wild males. We examine the effects of diet on the successive hurdles males must overcome in order to inseminate females, i.e., joining leks, copulating females, having their sperm stored and inhibition of female remating. In addition, we address the effects of diet on post-release foraging success, longevity, and the ability to withstand starvation. While protein feeding universally increases the sexual success of wild males, its effect on sterile males varies with strain, experimental settings, and environmental conditions. In some cases, treatments that resulted in the best sexual performance were significantly associated with increased vulnerability to starvation. However, no particular diet affected the ability of sterile males to find nutrients in the field when these where available. We suggest it may be better to release relatively short-lived flies that are highly competitive, rather than long-lived, sexually ineffective ones. (author) [es

Association between higher levels of sexual function, activity, and satisfaction and self-rated successful aging in older postmenopausal women

Science.gov (United States)

Thompson, Wesley K.; Charo, Lindsey; Vahia, Ipsit V.; Depp, Colin; Allison, Matthew; Jeste, Dilip V.

2014-01-01

Objectives To determine if measures of successful-aging are associated with sexual activity, satisfaction, and function in older post-menopausal women. Design Cross-sectional study using self-report surveys; analyses include chi-square and t-tests and multiple linear regression analyses. Setting Community-dwelling older post-menopausal women in the greater San Diego Region. Participants 1,235 community-dwelling women aged 60-89 years participating at the San Diego site of the Women's Health Initiative. Measurements Demographics and self-report measures of sexual activity, function, and satisfaction and successful aging. Results Sexual activity and functioning (desire, arousal, vaginal tightness, use of lubricants, and ability to climax) were negatively associated with age, as were physical and mental health. In contrast, sexual satisfaction and self-rated successful aging and quality of life remained unchanged across age groups. Successful aging measures were positively associated with sexual measures, especially self-rated quality of life and sexual satisfaction. Conclusions Self-rated successful aging, quality of life, and sexual satisfaction appear to be stable in the face of declines in physical health, some cognitive abilities, and sexual activity and function and are positively associated with each other across ages 60-89 years. PMID:21797827

Differences and similarities in sexual and contraceptive knowledge, attitudes, and behavior among Latino male adolescent students in California, United States and Lima, Peru

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Chirinos Jesús L.

2001-01-01

Full Text Available To identify the differences and similarities in sexual and contraceptive knowledge, attitudes, and behavior among Latino male adolescent students living in California and Lima. Self-administered, anonymous surveys were completed by Latino male students aged 12-19 participating in California, and by male adolescent students in four high schools in Lima. Both surveys contained similar questions allowing for comparisons regarding sexual activity and contraceptive behavior. The mean age of male students were 16 and 15 years, respectively. More California males reported having engaged in sexual intercourse (69% vs 43%. The sexual debut was 13 years in both samples. More students in California were aware of their risk of pregnancy at first sexual intercourse than in Lima (82% vs 50%. One-third of the California males reported communicating with their partner about sex and contraception to be "easy" as compared to 53% of males in Lima. More students in California reported knowing a place to obtain contraceptives if they need them (85% vs 63%, having ever gotten someone pregnant (29% vs 7%, and having fathered a child (67% vs 16%.

Sexual characteristics of male guppies Poecilia reticulata serve as effect biomarkers of estrogens

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Tian, Hua; Li, Yun; Wang, Wei; Zhao, Fei; Gao, Su; Ru, Shaoguo

2017-10-01

Guppies (Poecilia reticulata) are considered a candidate model species for the identification and testing of endocrine-disrupting chemicals. Male guppies may be used to address the challenge of making potential linkages between alterations of biomarkers, both at the cellular and organ level, and adverse outcomes. In the present study, a predictive relationship between sex characteristics and reproductive output was observed in male guppies that underwent a long-term toxicity test with 0.5 μg/L 17β-estradiol administered during the juvenile period. Radioimmunoassay and western blot analyses demonstrated that 17β-estradiol exposure caused a significant increase in testicular 17β-estradiol levels as well as the induction of exposure biomarkers, namely hepatic vitellogenin. Exposure to 17β-estradiol also caused a significant decrease in testosterone levels, which consequently reduced the gonadosomatic index, sperm counts, and the coloration index. These changes of male sexual characteristics further translated into adverse influences on reproduction, as measured by a decrease in off spring production and survival rate. Our results suggest that the above-mentioned sexual characteristics of male guppies may be considered potential in vivo biomarkers of estrogen effects on reproduction.

Aggression Toward Gay Men as Gender Role Enforcement: Effects of Male Role Norms, Sexual Prejudice, and Masculine Gender Role Stress

Science.gov (United States)

Parrott, Dominic J.

2009-01-01

This study examined sexual prejudice and masculine gender role stress as mediators of the relations between male gender norms and anger and aggression toward gay men. Participants were 150 self-identified heterosexual men who completed measures of adherence to male gender role norms, sexual prejudice, masculine gender role stress, and state anger. Participants then viewed a video depicting intimate relationship behavior between two gay men, reported state anger a second time, and competed in a laboratory aggression task against either a heterosexual or a gay male. Results indicated that adherence to the antifemininity norm exerted an indirect effect, primarily through sexual prejudice, on increases in anger. Adherence to the status and antifemininity norms exerted indirect effects, also through sexual prejudice, on physical aggression toward the gay, but not the heterosexual, male. Findings provide the first multivariate evidence for determinants of aggression toward gay men motivated by gender role enforcement. PMID:19558440

Perspectives on Sexual Health and Function of Recent Male Combat Veterans of Iraq and Afghanistan

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Drew A. Helmer, MD, MS

2015-09-01

Conclusions: Sexual dysfunction in recent combat veterans can have important negative effects on their health and relationships. Our findings elucidate perceived contributory factors and preferred solutions, which can be applied by health‐care providers to improve the management of sexual dysfunction in these patients. Helmer DA, Beaulieu G, Powers C, Houlette C, Latini D, and Kauth M. Perspectives on sexual health and function of recent male combat veterans of Iraq and Afghanistan. Sex Med 2015;3:137–146.

Exploring the Overlap in Male Juvenile Sexual Offending and General Delinquency: Trauma, Alcohol Use, and Masculine Beliefs

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Brown, Adam; Burton, David L.

2010-01-01

Despite Burton and Meezan's (2004) finding that sexually aggressive youth are three to four times more likely to recidivate nonsexually than sexually, there is little to no research to date that explores this overlap in criminality. With a sample of 290 male sexually violent adjudicated and incarcerated youth, this study was able to successfully…

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

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

2014-01-01

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

Exploring urban male non-marital sexual behaviours in Pakistan.

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Mir, Ali M; Wajid, Abdul; Pearson, Stephen; Khan, Mumraiz; Masood, Irfan

2013-04-11

In Pakistan, sexual practices outside marriage are proscribed by law. We aimed to assess the range and magnitude of non-marital sexual behaviours of urban men, focusing on men having sex with men. In this cross sectional survey undertaken in six cities of Pakistan, we interviewed 2400 men aged 16-45 years selected through a multistage systematic sampling design. Sexual behaviours were assessed through a structured questionnaire. Multivariable analysis was used to identify association between various individual level characteristics and probability of engaging in sexual activities involving men. Nearly one-third (29 percent) reported having had non-marital sex in their lifetime. Of these men 16 percent reported premarital sex, while 11 percent reported engaging in both pre- and extramarital sex. Only two percent reported exclusive extramarital sex. In total 211 respondents, 9 percent reported ever having had sexual relations with men. While 62 respondents, 2.6 percent reported exclusive sex with males. Factors that were significantly associated with MSM behaviours were being less than 27 years (adjusted OR 5.4, 95% CI 3.8-7.7, p pornographic materials (adjusted OR 4.8, 95% CI 3.0-7.7, p pornographic materials (adjusted OR 3.3, 95% CI: 1.5-7.2, p = 0.002). To prevent the spread of STI's in Pakistan, preventive interventions should focus on reaching out to young uneducated men offering them with appropriate counselling and skills to adopt "safe sex practices" through workplace orientation sessions; while for youth in schools, life skills education be included in the curriculum. Through public-private partnership stigmatised groups should be reached through established community networks and provided with information on accessing voluntary counseling and treatment centres.

Signal trait sexual dimorphism and mutual sexual selection in Drosophila serrata.

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Chenoweth, Stephen F; Blows, Mark W

2003-10-01

The evolution of sexual dimorphism may occur when natural and sexual selection result in different optimum trait values for males and females. Perhaps the most prominent examples of sexual dimorphism occur in sexually selected traits, for which males usually display exaggerated trait levels, while females may show reduced expression of the trait. In some species, females also exhibit secondary sexual traits that may either be a consequence of a correlated response to sexual selection on males or direct sexual selection for female secondary sexual traits. In this experiment, we simultaneously measure the intersex genetic correlations and the relative strength of sexual selection on males and females for a set of cuticular hydrocarbons in Drosophila serrata. There was significant directional sexual selection on both male and female cuticular hydrocarbons: the strength of sexual selection did not differ among the sexes but males and females preferred different cuticular hydrocarbons. In contrast with many previous studies of sexual dimorphism, intersex genetic correlations were low. The evolution of sexual dimorphism in D. serrata appears to have been achieved by sex-limited expression of traits controlled by genes on the X chromosome and is likely to be in its final stages.

Sexual dysfunction among youth: an overlooked sexual health concern.

Science.gov (United States)

Moreau, Caroline; Kågesten, Anna E; Blum, Robert Wm

2016-11-18

There is growing recognition that youth sexual health entails a broad range of physical, emotional and psychosocial responses to sexual interactions, yet little is known about sexual dysfunctions and well being in youth populations. This study explored sexual dysfunctions among youth and its associations with other domains of sexual health. Sexual dysfunctions were defined as: problems related to orgasm, pain during intercourse, lack of sexual desire or sexual pleasure. Data were drawn from the 2010 French national sexual and reproductive health survey comprising a random sample of 2309 respondents aged 15-24 years. The current analysis included 842 females and 642 males who had sexual intercourse in the last 12 months. Chi square tests were used to test for differences in sexual dysfunctions by sex and explore associations with other domains of sexual health. Half of females (48%) reported at least one sexual dysfunction versus 23% of males. However, over half (57%) of youth reporting at least one dysfunction did not consider this to hinder their sexuality. Altogether, 31% of females cited at least one sexual dysfunction hindering their sexuality-more than three times the 9% of males. Sexual dysfunction was strongly and inversely related to sexual satisfaction for both males and females and additionally to a recent diagnosis of STI or unintended pregnancy for females. Sexual dysfunctions hindering sexuality were also correlated with a history of unintended pregnancy among males. While most youth in France enjoy a satisfying sexual life, sexual dysfunction is common, especially among females. Public health programs and clinicians should screen for and address sexual dysfunction, which substantially reduce youth sexual wellbeing.

Knockout mutations of insulin-like peptide genes enhance sexual receptivity in Drosophila virgin females.

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Watanabe, Kazuki; Sakai, Takaomi

2016-01-01

In the fruitfly Drosophila melanogaster, females take the initiative to mate successfully because they decide whether to mate or not. However, little is known about the molecular and neuronal mechanisms regulating sexual receptivity in virgin females. Genetic tools available in Drosophila are useful for identifying molecules and neural circuits involved in the regulation of sexual receptivity. We previously demonstrated that insulin-producing cells (IPCs) in the female brain are critical to the regulation of female sexual receptivity. Ablation and inactivation of IPCs enhance female sexual receptivity, suggesting that neurosecretion from IPCs inhibits female sexual receptivity. IPCs produce and release insulin-like peptides (Ilps) that modulate various biological processes such as metabolism, growth, lifespan and behaviors. Here, we report a novel role of the Ilps in sexual behavior in Drosophila virgin females. Compared with wild-type females, females with knockout mutations of Ilps showed a high mating success rate toward wild-type males, whereas wild-type males courted wild-type and Ilp-knockout females to the same extent. Wild-type receptive females retard their movement during male courtship and this reduced female mobility allows males to copulate. Thus, it was anticipated that knockout mutations of Ilps would reduce general locomotion. However, the locomotor activity in Ilp-knockout females was significantly higher than that in wild-type females. Thus, our findings indicate that the high mating success rate in Ilp-knockout females is caused by their enhanced sexual receptivity, but not by improvement of their sex appeal or by general sluggishness.

[The responsiveness of males having suffered forced displacement regarding their risk of contracting sexually-transmitted infection].

Science.gov (United States)

Vásquez-Salazar, Edwin A; Ochoa-Marín, Sandra C; Duarte, María B

2012-10-01

Describing displaced males' responsiveness regarding issues concerning sexual and reproductive health, particularly contracting STI/HIV/AIDS. An ethnographic study concerning displaced males who were living in shelters was carried out in Medellín, Colombia, from March to November 2010; observation and semi-structured interview techniques were used. Nineteen men(with and without a partner) aged 18 to 60 years old were interviewed; they had been suffering the effects of forced displacement for less than 1 year. The results were analyzed following grounded theory guidelines. Three main categories were analyzed: having been forcibly displaced and such impact on their daily life, issues related to their sexuality and their ability to respond. Despite forcibly displaced male shaving information about condo muse and perceiving the risk posed by STI/HIV/AIDS, they did not take preventative measures when engaging in their sexual practices and most assumed various risky behavior patterns. Living conditions in the hostel, few job opportunities and the culture regarding machismo increased the risk of acquiring an STI and decreased their responsiveness to them. Responsiveness to STI/HIV/AID Sin males who had been experiencing the hardships of having been recently displaced was seen to have become reduced because of the material and psychosocial conditions which they had to face. Policies and programs addressing this group's specific needs are required which are aimed at improving information regarding sexual and reproductive health, access to services and opportunities for decent work.

Sexual dysfunction among youth: an overlooked sexual health concern

Directory of Open Access Journals (Sweden)

Caroline Moreau

2016-11-01

Full Text Available Abstract Background There is growing recognition that youth sexual health entails a broad range of physical, emotional and psychosocial responses to sexual interactions, yet little is known about sexual dysfunctions and well being in youth populations. This study explored sexual dysfunctions among youth and its associations with other domains of sexual health. Sexual dysfunctions were defined as: problems related to orgasm, pain during intercourse, lack of sexual desire or sexual pleasure. Methods Data were drawn from the 2010 French national sexual and reproductive health survey comprising a random sample of 2309 respondents aged 15-24 years. The current analysis included 842 females and 642 males who had sexual intercourse in the last 12 months. Chi square tests were used to test for differences in sexual dysfunctions by sex and explore associations with other domains of sexual health. Results Half of females (48% reported at least one sexual dysfunction versus 23% of males. However, over half (57% of youth reporting at least one dysfunction did not consider this to hinder their sexuality. Altogether, 31% of females cited at least one sexual dysfunction hindering their sexuality—more than three times the 9% of males. Sexual dysfunction was strongly and inversely related to sexual satisfaction for both males and females and additionally to a recent diagnosis of STI or unintended pregnancy for females. Sexual dysfunctions hindering sexuality were also correlated with a history of unintended pregnancy among males. Conclusion While most youth in France enjoy a satisfying sexual life, sexual dysfunction is common, especially among females. Public health programs and clinicians should screen for and address sexual dysfunction, which substantially reduce youth sexual wellbeing.

Guppy sexual behavior as an effect biomarker of estrogen mimics

DEFF Research Database (Denmark)

Bayley, M; Nielsen, J R; Baatrup, E

1999-01-01

There is widespread concern that some environmental chemicals can reduce the reproductive capability of humans and wildlife by mimicking natural estrogens and disrupting endocrine function. This potential threat to animal populations posed by xenoestrogens has, hardly surprisingly, been met...... strongly on the ability to perform the appropriate sexual behavior. The sexual display of the male guppy is strongly linked to reproductive success and is readily quantified under laboratory conditions. This preliminary study demonstrates that exposure of adult male guppies to water weakly contaminated...... with either natural estrogen (17beta-estradiol) or the xenoestrogen (4-tert-octylphenol) causes a dramatic decrease in the rate and intensity of sexual display. It is concluded that quantitative analysis of the sexual display of male guppies holds great promise as a biomarker at the organismal level...

Condom Use at Last Sexual Intercourse and Its Correlates among Males and Females Aged 15–49 Years in Nepal

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Bimala Sharma

2018-03-01

Full Text Available This study aimed to assess the prevalence and correlates of condom use at last sexual intercourse among people aged 15–49 years in Nepal. Secondary data analysis was performed using the Nepal Demographic and Health Survey 2011. The study was restricted to the respondents who reported ever having had sexual intercourse; 9843 females and 3017 males were included. Condom use was assessed by asking if respondents used condoms in their most recent sexual intercourse. Chi-square test and multivariate logistic regression analysis were performed using Complex Sample Analysis Procedure to adjust for sample weight and multistage sampling design. Overall, 7.6% of total, and 16.3% of males and 6.2% of females reported using condoms in their last sexual intercourse. Living in Far-Western region, age and wealth quintile were positively associated with condom use in both males and females. Being unmarried was the most important predictor of condom use among males. Higher education was associated with increased likelihood of condom use in females. However, mobility, having multiple sexual partners, and HIV knowledge were not significant correlates of condom use in both sexes. A big difference was observed in the variance accounted for males and females; indicating use of condoms is poorly predicted by the variables included in the study among females. Condom use was more associated with sociodemographic factors than with sexual behavior and HIV knowledge.

Study success in higher education: male versus female students

NARCIS (Netherlands)

Kolster, Renze; Kaiser, Franciscus

2015-01-01

Study success is an important topic for countries concerned with the effectiveness of their higher education system. A closer look at study success outcomes suggests there are noticeable differences between male and female students: in terms of enrolment, study choices, drop‐out rates, retention

Gender differences in experiences of sexual harassment: data from a male-dominated environment.

Science.gov (United States)

Street, Amy E; Gradus, Jaimie L; Stafford, Jane; Kelly, Kacie

2007-06-01

The goal of this investigation was to examine gender differences in experiences of sexual harassment during military service and the negative mental health symptoms associated with these experiences. Female (n = 2,319) and male (n = 1,627) former reservists were surveyed about sexual harassment during their military service and current mental health symptoms. As expected, women reported a higher frequency of sexual harassment. Further, women had increased odds of experiencing all subtypes of sexual harassment. Being female conferred the greatest risk for experiencing the most serious forms of harassment. For both men and women, sexual harassment was associated with more negative current mental health. However, at higher levels of harassment, associations with some negative mental health symptoms were stronger for men than women. Although preliminary, the results of this investigation suggest that although women are harassed more frequently than men, clinicians must increase their awareness of the potential for sexual harassment among men in order to provide the best possible care to all victims of harassment. Copyright 2007 APA.

Genetic variation of male reproductive success in a laboratory population of Anopheles gambiae

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Voordouw Maarten J

2007-07-01

Full Text Available Abstract Background For Anopheline mosquitoes, the vectors of human malaria, genetic variation in male reproductive success can have important consequences for any control strategy based on the release of transgenic or sterile males. Methods A quantitative genetics approach was used to test whether there was a genetic component to variation in male reproductive success in a laboratory population of Anopheles gambiae. Swarms of full sibling brothers were mated with a fixed number of females and their reproductive success was measured as (1 proportion of ovipositing females, (2 proportion of ovipositing females that produced larvae, (3 proportion of females that produced larvae, (4 number of eggs laid per female, (5 number of larvae per ovipositing female and (6 number of larvae per female. Results The proportion of ovipositing females (trait 1 and the proportion of ovipositing females that produced larvae (trait 2 differed among full sib families, suggesting a genetic basis of mating success. In contrast, the other measures of male reproductive success showed little variation due to the full sib families, as their variation are probably mostly due to differences among females. While age at emergence and wing length of the males were also heritable, they were not associated with reproductive success. Larger females produced more eggs, but males did not prefer such partners. Conclusion The first study to quantify genetic variation for male reproductive success in A. gambiae found that while the initial stages of male reproduction (i.e. the proportion of ovipositing females and the proportion of ovipositing females that produced larvae had a genetic basis, the overall reproductive success (i.e. the mean number of larvae per female did not.

Negotiating the "White Male Math Myth": African American Male Students and Success in School Mathematics

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Stinson, David W.

2013-01-01

This article shows how equity research in mathematics education can be decentered by reporting the "voices" of mathematically successful African American male students as they recount their experiences with school mathematics, illustrating, in essence, how they negotiated the White male math myth. Using post-structural theory, the…

Negotiating sexual safety in the era of biomedical HIV prevention: relationship dynamics among male couples using pre-exposure prophylaxis.

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Malone, Jowanna; Syvertsen, Jennifer L; Johnson, Blake E; Mimiaga, Matthew J; Mayer, Kenneth H; Bazzi, Angela R

2018-06-01

Up to two-thirds of new cases of HIV transmission between gay, bisexual and other men who have sex with men in the USA are attributed to primary relationships. Understanding the relationship dynamics and sexual agreements of male-male couples can provide insight into HIV transmission patterns and prevention needs in this population. The daily use of antiretroviral pre-exposure prophylaxis (PrEP) is highly effective in preventing HIV, but its negotiation and use within social and intimate relationship contexts remain understudied. We conducted semi-structured qualitative interviews with 20 male couples (n = 40 men) in which at least one partner was either using or in the process of initiating PrEP. Congruent with a theoretical focus on social theories of relationships and negotiated risk, couples were interviewed about relationship dynamics, trust, communication and sexual health practices, including their perception and use of PrEP. Overall, we found that couples showed heightened trust and communication when establishing open, sexual agreements and demonstrated high awareness of sexual risks and health practices in the context of PrEP use. This study demonstrates how understanding relationship dynamics can better inform HIV prevention and sexual health promotion efforts for male couples at risk of HIV.

Promoting the Academic Engagement and Success of Black Male Student-Athletes

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Harris, Paul C.; Hines, Erik M.; Kelly, Darren D.; Williams, Derick J.; Bagley, Bethany

2014-01-01

The goal of this study was to provide a qualitative look at the factors associated with the academic engagement and success of Black male student-athletes in high school. The research team employed a thematic analysis to examine semi-structured interviews conducted with two successful Black male student-athletes, along with their principal,…

Promoting sexual health: practical guidance on male condom use.

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Flannigan, Jason

Condoms are the only form of contraception that, when used correctly, can reduce the risk of pregnancy and transmission of sexually transmitted infections. This article outlines strategies for promoting correct male condom use. The availability, variety and history of condoms are explored. Possible reasons for people not wanting to use condoms are examined and advantages of condom use are provided. The author suggests ways in which healthcare workers can promote condom use and improve the experience and efficacy of this contraceptive device.

Postnatal nutrition influences male attractiveness and promotes plasticity in male mating preferences

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Noguera, José C.; Metcalfe, Neil B.; Monaghan, Pat

2017-12-01

Poor early-life nutrition could reduce adult reproductive success by negatively affecting traits linked to sexual attractiveness such as song complexity. If so, this might favor strategic mate choice, allowing males with less complex songs to tailor their mating tactics to maximize the reproductive benefits. However, this possibility has been ignored in theoretical and empirical studies. By manipulating the micronutrient content of the diet (e.g., low or high) during the postnatal period of male zebra finches, we show for the first time (1) that males reared on a poor (low) micronutrient diet had less complex songs as adults; (2) that these males, in contrast to the high micronutrient diet group, were more selective in their mating strategies, discriminating against those females most likely to reduce their clutch size when paired with males having less complex songs; and (3) that by following different mating strategies, males reared on the contrasting diets obtained similar reproductive benefits. These results suggest that early-life dietary conditions can induce multiple and long-lasting effects on male and female reproductive traits. Moreover, the results seem to reflect a previously unreported case of adaptive plasticity in mate choice in response to a nutritionally mediated reduction in sexual attractiveness.

[Between contradictions and risks: Mexican male adolescents' views about teenage pregnancy and its association with sexual behavior].

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Quiroz, Jorge; Atienzo, Erika E; Campero, Lourdes; Suárez-López, Leticia

2014-04-01

To explore the opinions of Mexican male adolescents regarding teenage pregnancy and analyze its association with sexual behavior. This is a cross-sectional study using a self-administered questionnaire among a conventional sample of male students (15-19 years old) in eight public schools in Morelos and Mexico City. Analyses include multivariate models to identify the association between opinions and sexual behaviors. Overall, 68% agree that a teenage pregnancy is a negative event. In a hypothetical case, if a girlfriend got pregnant in this moment 56% would continue in the school whereas 18% would definitely abandon it. Those who affirm that a teenage pregnancy is something very bad have greater odds of using condoms (OR=1.8; pteenage pregnancy are associated with some sexual behaviors; however their opinions reflect several contradictions. The design of surveys directed exclusively to explore male adolescents' opinions about reproductive health is urgent.

Mating choice of Ceratitis capitata (Wiedemann) (Diptera: Tephritidae): influence of male ageing on mating success

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Silva Neto, Alberto M. da; Dias, Vanessa S.; Joachim-Bravo, Iara S.

2009-01-01

The objective of this study was to evaluate the effect of male ageing on male pheromone release and mating success of Ceratitis capitata (Wiedemann). The effects of male ageing on mating were evaluated on fi ve and 21 d-old males by assessing their mating success (males chosen by a female for copulation) and the amount of males releasing the sex pheromone. The mating success was evaluated by using several ratios of young to older males by increasing the number of older males:young males from 1:1 to 5:1. The mating success of the 1:1 ratio was also evaluated in fi eld cages. The evaluation of the mating success (in the 1:1 ratio) showed a clear preference of the females for young males. Sex pheromone emission was much more common on young than older males. Even in cases were older males were more abundant (ratios 2:1 and 3:1), females still chose the young males. However, females could not distinguish young from older males in ratios of 4:1 or 5:1. Our data indicate that the ageing of C. capitata males has a considerable negative effect on their reproductive success, especially if they are found in a proportion any lower than 3:1. (author)

Coloured leg bands affect male mate-guarding behaviour in the bluethroat

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Johnsen; Lifjeld; Rohde

1997-07-01

Artificial traits such as coloured leg bands may affect an individual's mating success, as shown for some birds. One explanation is that colour-matching with a sexual ornament affects the individual's sexual attractiveness. This study reports a colour-band experiment with free-living bluethroats, Luscinia s. svecicaa species where males have a distinct blue and chestnut throat and upper breast. There was no apparent difference in pairing success between males with ornament-matching colour bands (blue and orange) and males with non-ornamental colour bands. However, males with ornamental bands guarded their mates less intensely and spent more time singing, performing song flights and intruding into neighbours' territories than males with non-ornamental bands. We conclude that colour bands affect the trade-off between mate guarding and advertisement behaviour in a way that is consistent with the hypothesis that bands with ornamental colours improve a male's attractiveness. The results are in concordance with a previous study of the same population, showing that males with experimentally reduced attractiveness guarded their mates more closely and advertised less for additional mates, than non-manipulated males.

Sexual competion of irradiated males of the cowpea weevil, callosobruchus maculatus (F.)

International Nuclear Information System (INIS)

Ahmed, M.Y.Y.; Younes, M.W.F.

1981-01-01

When unmated males of Callosobruchus maculatus were irradiated with 7.5 or 10 Krad and confined with normal females, 97.90 and 89.32%, respectively, of the eggs did not hatch, compared with 15.49% infertility of the control eggs. Increasing the dose to 12.5 or 15 Krad induced 99.44 and 100%, respectively, sterility in the irradiated (I) males. When males treated with 7.5, 10 or 12.5 Krad were confined with unirradiated (U) males and females (1:1:1 ratio), infertility of the resulting eggs were 60.06, 67.96 and 69.04%, respectively. The competitiveness values of irradiated males with the above doses and ratio were 1.2, 1.6 and 1.8. Thus, males treated with substerilizing doses (7.5, 10 or 12.5 Krad) competed favourably with (U) males, and males treated with the sterilizing dose (15 Krad) were also fully competitive with (U) males. These results indicated that irradiation with 15 Krad, a sterilizing dose, did not decrease sexual competitiveness of irradiated males. (author)

Psychosocial profile of male patients presenting with sexual dysfunction in a psychiatric outpatient department in Mumbai, India

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Kalra, Gurvinder; Kamath, Ravindra; Subramanyam, Alka; Shah, Henal

2015-01-01

Introduction: Sexual dysfunction can occur due to biological problems, relationship problems, lack of proper sexual knowledge or a combination of these. India is often known as the land of Kamasutra. But as far as sexuality research is concerned, there is a paucity of relevant data from India. In view of this, we conducted a study to assess the psychosocial profile of males presenting with sexual dysfunction to psychiatry out-patient department of a tertiary medical hospital. Materials and Methods: Hundred consecutive male patients presenting with sexual dysfunction were screened using Arizona Sexual Experiences Scale for clinical sexual dysfunction and after obtaining their informed consent were included in this study. They were assessed using a semi-structured proforma, Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision criteria, Mini-International Neuropsychiatric Interview, and Dyadic Adjustment Scale. Results: Majority of our respondents were in the 18–30 years age group and were married. The main source of sex knowledge for 69% of them was peer group. Age of onset of masturbation was 11–13 years for 43% of them. Premature ejaculation was the most common sexual dysfunction seen in the respondents. Marital discord was seen in significantly lesser number of respondents (32.35%) as also major depressive disorder that was seen in only 16%. Discussion: Premature ejaculation was the most common sexual dysfunction in our sample. Despite the sexual dysfunction, marital discord and depression were seen less commonly in our respondents. PMID:25657457

Psychosocial profile of male patients presenting with sexual dysfunction in a psychiatric outpatient department in Mumbai, India.

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Kalra, Gurvinder; Kamath, Ravindra; Subramanyam, Alka; Shah, Henal

2015-01-01

Sexual dysfunction can occur due to biological problems, relationship problems, lack of proper sexual knowledge or a combination of these. India is often known as the land of Kamasutra. But as far as sexuality research is concerned, there is a paucity of relevant data from India. In view of this, we conducted a study to assess the psychosocial profile of males presenting with sexual dysfunction to psychiatry out-patient department of a tertiary medical hospital. Hundred consecutive male patients presenting with sexual dysfunction were screened using Arizona Sexual Experiences Scale for clinical sexual dysfunction and after obtaining their informed consent were included in this study. They were assessed using a semi-structured proforma, Diagnostic and Statistical Manual of Mental Disorders, 4(th) Edition, Text Revision criteria, Mini-International Neuropsychiatric Interview, and Dyadic Adjustment Scale. Majority of our respondents were in the 18-30 years age group and were married. The main source of sex knowledge for 69% of them was peer group. Age of onset of masturbation was 11-13 years for 43% of them. Premature ejaculation was the most common sexual dysfunction seen in the respondents. Marital discord was seen in significantly lesser number of respondents (32.35%) as also major depressive disorder that was seen in only 16%. Premature ejaculation was the most common sexual dysfunction in our sample. Despite the sexual dysfunction, marital discord and depression were seen less commonly in our respondents.

High male sexual investment as a driver of extinction in fossil ostracods.

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Martins, Maria João Fernandes; Puckett, T Markham; Lockwood, Rowan; Swaddle, John P; Hunt, Gene

2018-04-01

Sexual selection favours traits that confer advantages in the competition for mates. In many cases, such traits are costly to produce and maintain, because the costs help to enforce the honesty of these signals and cues 1 . Some evolutionary models predict that sexual selection also produces costs at the population level, which could limit the ability of populations to adapt to changing conditions and thus increase the risk of extinction 2-4 . Other models, however, suggest that sexual selection should increase rates of adaptation and enhance the removal of deleterious mutations, thus protecting populations against extinction 3, 5, 6 . Resolving the conflict between these models is not only important for explaining the history of biodiversity, but also relevant to understanding the mechanisms of the current biodiversity crisis. Previous attempts to test the conflicting predictions produced by these models have been limited to extant species and have thus relied on indirect proxies for species extinction. Here we use the informative fossil record of cytheroid ostracods-small, bivalved crustaceans with sexually dimorphic carapaces-to test how sexual selection relates to actual species extinction. We show that species with more pronounced sexual dimorphism, indicating the highest levels of male investment in reproduction, had estimated extinction rates that were ten times higher than those of the species with the lowest investment. These results indicate that sexual selection can be a substantial risk factor for extinction.