A character demonstrating the occurrence of mating in male Cactoblastis cactorum (Lepidoptera: Pyralidae)

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Marti, O.G.; Carpenter, J.E.

2007-01-01

The reproductive system of adult male Cactoblastis cactorum, the cactus moth, was examined to determine whether the mating status of males could be ascertained. In unmated males, the posterior portion of the primary ductus ejaculatorius simplex is opaque yellow in color and contains many small football-shaped hyaline granules 3-5 x 5-10 μm in size. In mated males, the posterior simplex is clear and contains no granules. The presence or absence of these characters was found to be highly reliable and should be of value in determining mating status in marked-recaptured males of this species in a sterile insect release program directed against Cactoblastis. (author)

Representation of pheromones, interspecific signals, and plant odors in higher olfactory centers; mapping physiologically identified antennal-lobe projection neurons in the male heliothine moth

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Xin-Cheng eZhao

2014-10-01

Full Text Available In the primary olfactory centre of the moth brain, for example, a few enlarged glomeruli situated dorsally, at the entrance of the antennal nerve, are devoted to information about female-produced substances whereas a set of more numerous ordinary glomeruli receives input about general odorants. Heliothine moths are particularly suitable for studying central chemosensory mechanisms not only because of their anatomically separated systems for plant odours and pheromones but also due to their use of female-produced substances in communication across the species. Thus, the male-specific system of heliothine moths includes two sub arrangements, one ensuring attraction and mating behavior by carrying information about pheromones released by conspecifics, and the other reproductive isolation via signal information emitted from heterospecifics. Based on previous tracing experiments, a general chemotopic organization of the male-specific glomeruli has been demonstrated in a number of heliothine species. As compared to the well explored organization of the moth antennal lobe, demonstrating a non-overlapping representation of the biologically relevant stimuli, less is known about the neural arrangement residing at the following synaptic level, i.e. the mushroom body calyces and the lateral horn. In the study presented here, we have labelled physiologically characterized antennal-lobe projection neurons in males of the two heliothine species, Heliothis virescens and Helicoverpa assulta, for the purpose of mapping their target regions in the protocerebrum. In order to compare the representation of plant odours, pheromones, and interspecific signals in the higher brain regions of each species, we have created standard brain atlases and registered three-dimensional models of distinct uniglomerular projection neuron types into the relevant atlas.

Serum ferritin level is higher in male adolescents with obesity: results from the Korean National Health and Nutrition Examination Survey 2010

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Yeon Jin Jeon

2013-09-01

Full Text Available PurposePrevious reports show an association between high serum ferritin levels and metabolic syndrome (MS in adults. In adolescents, little information is available with obesity and serum ferritin levels.MethodsThis is a cross-sectional study. Data were obtained from the 5th Korean National Health and Nutrition Examination Survey (K-NHANES conducted during 2010 by the Korean Ministry of Health and Welfare. A total of 849 subjects aged 10-18 years participated in the 2010 survey. A body mass index (BMI ≥95th percentile for age and sex or a BMI ≥25 was used to diagnose as obesity.ResultsThe weighted prevalence of obesity was 13.4% (62/462 in male and 8.5% (33/387 in female. We observed significantly higher serum ferritin in male than in female (mean±standard error [SE], 50.5±2.3 µU/L vs. 30.6±1.3 µU/L; P<0.0001. In male, serum ferritin is positively correlated with age (P<0.0001. White blood cell (WBC count, serum fasting blood sugar, triglyceride (TG, total cholesterol, low-density lipoprotein, insulin, homeostasis model assessment-insulin resistance (HOMA-IR, systolic and diastolic blood pressure, and ferritin levels were higher and high-density lipoprotein (HDL were lower in the obesity than in the normal group. In female adolescents, WBC count, TG, insulin, and HOMA-IR were higher and HDL were lower in the obesity than in the normal group. In male, serum ferritin levels showed positive association with obesity (β=21.196, P=0.016.ConclusionSerum ferritin levels appear to be associated with obesity in Korean male adolescents.

Males collectively defend their one-male units against bachelor males in a multi-level primate society.

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Xiang, Zuo-Fu; Yang, Bang-He; Yu, Yang; Yao, Hui; Grueter, Cyril C; Garber, Paul A; Li, Ming

2014-07-01

Group-level male-male co-operation, which has been documented in several primate and non-primate societies, may be mutualistically advantageous to the participants when confronted with threats such as takeovers and cuckoldry by external males. Co-operation among members of distinct social units-while universal among humans-is extremely rare in non-human primates. We present the first observations of collective action or co-operation among males of different one-male units (OMU) in a multi-level society of Rhinopithecus roxellana. A total of 59 instances of male co-operation were recorded. Male co-operation included coordinated chasing, joint vigilance, and patrolling behavior directed at lone adult males trying to enter an OMU. Male co-operation was significantly more frequent during the mating season when the risk of incursions and extra-group paternity was higher. Paternity of infants born in the subsequent birth season and kin relationships among resident males were identified using microsatellite genotype. All infants were sired by OMU males, which we interpret as possible evidence for their success at thwarting mating attempts by satellite males. OMU males were principally unrelated suggesting that male co-operation is best understood in terms of the mutual direct benefits individuals obtain through collective action. Our findings lend support to the bachelor threat hypothesis in which the cooperative behavior of several individuals is more effective than the lone action of a single individual in providing mate defense. Our research has implications for understanding male bonding, higher-level collective action, and the evolution of social co-operation in human societies. © 2013 Wiley Periodicals, Inc.

Review of the Research Literature on Defining and Demonstrating Quality Teaching and Impact in Higher Education

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Strang, Lucy; Bélanger, Julie; Manville, Catriona; Meads, Catherine

2016-01-01

In March 2016, the Higher Education Academy (HEA) commissioned RAND Europe to conduct a literature review of research published since 2012, with the aim of identifying and summarising the key trends and issues in the literature on how "quality teaching" and its impact are currently being defined and demonstrated at higher education…

Maternal effects on male weaponry: female dung beetles produce major sons with longer horns when they perceive higher population density

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Buzatto Bruno A

2012-07-01

Full Text Available Abstract Background Maternal effects are environmental influences on the phenotype of one individual that are due to the expression of genes in its mother, and are expected to evolve whenever females are better capable of assessing the environmental conditions that their offspring will experience than the offspring themselves. In the dung beetle Onthophagus taurus, conditional male dimorphism is associated with alternative reproductive tactics: majors fight and guard females whereas minors sneak copulations. Furthermore, variation in dung beetle population density has different fitness consequences for each male morph, and theory predicts that higher population density might select for a higher frequency of minors and/or greater expenditure on weaponry in majors. Because adult dung beetles provide offspring with all the nutritional resources for their development, maternal effects strongly influence male phenotype. Results Here we tested whether female O. taurus are capable of perceiving population density, and responding by changing the phenotype of their offspring. We found that mothers who were reared with other conspecifics in their pre-mating period produced major offspring that had longer horns across a wider range of body sizes than the major offspring of females that were reared in isolation in their pre-mating period. Moreover, our results indicate that this maternal effect on male weaponry does not operate through the amount of dung provided by females to their offspring, but is rather transmitted through egg or brood mass composition. Finally, although theory predicts that females experiencing higher density might produce more minor males, we found no support for this, rather the best fitting models were equivocal as to whether fewer or the same proportions of minors were produced. Conclusions Our study describes a new type of maternal effect in dung beetles, which probably allows females to respond to population density adaptively

Seasonal variation in male alternative reproductive tactics.

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Monroe, M J; Amundsen, T; Utne-Palm, A C; Mobley, K B

2016-12-01

Genetic parentage analyses reveal considerable diversity in alternative reproductive behaviours (e.g. sneaking) in many taxa. However, little is known about whether these behaviours vary seasonally and between populations. Here, we investigate seasonal variation in male reproductive behaviours in a population of two-spotted gobies (Gobiusculus flavescens) in Norway. Male two-spotted gobies guard nests, attract females and care for fertilized eggs. We collected clutches and nest-guarding males early and late in the breeding season in artificial nests and used microsatellite markers to reconstruct parentage from a subset of offspring from each nest. We hypothesized that mating, reproductive success and sneaking should be more prevalent early in the breeding season when competition for mates among males is predicted to be higher. However, parentage analyses revealed similar values of mating, reproductive success and high frequencies of successful sneaking early (30% of nests) and late (27% of nests) in the season. We also found that multiple females with eggs in the same nest were fertilized by one or more sneaker males, indicating that some males in this population engage in a satellite strategy. We contrast our results to previous work that demonstrates low levels of cuckoldry in a population in Sweden. Our results demonstrate marked stability in both the genetic mating system and male alternative reproductive tactics over the breeding season. However, sneaking rates may vary geographically within a species, likely due to local selection influencing ecological factors encountered at different locations. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

The Salience of Gender during the Transition to Higher Education: Male Students' Accounts of Performed and Authentic Identities

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Warin, Jo; Dempster, Steve

2007-01-01

This article looks at the transition to higher education made by a group of male undergraduates. The data were collected though one-to-one interviews with 24 students, who were asked questions designed to elicit data about their positioning in relation to hegemonic masculinities. The evidence presented here supports the view that gender operates…

Higher body mass index is associated with greater severity of alopecia in men with male-pattern androgenetic alopecia in Taiwan: a cross-sectional study.

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Yang, Chao-Chun; Hsieh, Fu-Nien; Lin, Li-Yu; Hsu, Chao-Kai; Sheu, Hamm-Ming; Chen, WenChieh

2014-02-01

Obesity is a risk factor for multiple health problems, but its association with androgenetic alopecia (AGA) remains controversial. We sought to determine the association between body mass index (BMI) and alopecia severity in men with AGA and early-onset AGA. A cross-sectional study was conducted. The medical charts and photographs of men with a clinical diagnosis of AGA were reviewed. In all, 189 men were enrolled with a mean age of 30.8 years. In male-pattern AGA (n = 142), men with severe alopecia (grade V-VII) had higher BMI than those with mild to moderate alopecia (grade I-IV) (25.1 vs 22.8 kg/m(2), P = .01). After multivariate adjustments, the risk for severe alopecia was higher in the overweight or obese (BMI ≥24 kg/m(2)) subjects with male-pattern AGA (odds ratio 3.52, P < .01). In early-onset male-pattern AGA (n = 46), the risk for having severe alopecia was also higher in the overweight or obese subjects (odds ratio 4.97, P = .03). Parameters used to evaluate obesity were limited because of the retrospective nature of the study. Higher BMI was significantly associated with greater severity of hair loss in men with male-pattern AGA, especially in those with early-onset AGA. Copyright © 2013 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.

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.

Game Performance Evaluation in Male Goalball Players

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Molik, Bartosz; Morgulec-Adamowicz, Natalia; Kosmol, Andrzej; Perkowski, Krzysztof; Bednarczuk, Grzegorz; Skowroński, Waldemar; Gomez, Miguel Angel; Koc, Krzysztof; Rutkowska, Izabela; Szyman, Robert J

2015-01-01

Goalball is a Paralympic sport exclusively for athletes who are visually impaired and blind. The aims of this study were twofold: to describe game performance of elite male goalball players based upon the degree of visual impairment, and to determine if game performance was related to anthropometric characteristics of elite male goalball players. The study sample consisted of 44 male goalball athletes. A total of 38 games were recorded during the Summer Paralympic Games in London 2012. Observations were reported using the Game Efficiency Sheet for Goalball. Additional anthropometric measurements included body mass (kg), body height (cm), the arm span (cm) and length of the body in the defensive position (cm). The results differentiating both groups showed that the players with total blindness obtained higher means than the players with visual impairment for game indicators such as the sum of defense (p = 0.03) and the sum of good defense (p = 0.04). The players with visual impairment obtained higher results than those with total blindness for attack efficiency (p = 0.04), the sum of penalty defenses (p = 0.01), and fouls (p = 0.01). The study showed that athletes with blindness demonstrated higher game performance in defence. However, athletes with visual impairment presented higher efficiency in offensive actions. The analyses confirmed that body mass, body height, the arm span and length of the body in the defensive position did not differentiate players’ performance at the elite level. PMID:26834872

Game Performance Evaluation in Male Goalball Players

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Molik Bartosz

2015-12-01

Full Text Available Goalball is a Paralympic sport exclusively for athletes who are visually impaired and blind. The aims of this study were twofold: to describe game performance of elite male goalball players based upon the degree of visual impairment, and to determine if game performance was related to anthropometric characteristics of elite male goalball players. The study sample consisted of 44 male goalball athletes. A total of 38 games were recorded during the Summer Paralympic Games in London 2012. Observations were reported using the Game Efficiency Sheet for Goalball. Additional anthropometric measurements included body mass (kg, body height (cm, the arm span (cm and length of the body in the defensive position (cm. The results differentiating both groups showed that the players with total blindness obtained higher means than the players with visual impairment for game indicators such as the sum of defense (p = 0.03 and the sum of good defense (p = 0.04. The players with visual impairment obtained higher results than those with total blindness for attack efficiency (p = 0.04, the sum of penalty defenses (p = 0.01, and fouls (p = 0.01. The study showed that athletes with blindness demonstrated higher game performance in defence. However, athletes with visual impairment presented higher efficiency in offensive actions. The analyses confirmed that body mass, body height, the arm span and length of the body in the defensive position did not differentiate players’ performance at the elite level.

Androgens increase lws opsin expression and red sensitivity in male three-spined sticklebacks.

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Yi Ta Shao

Full Text Available Optomotor studies have shown that three-spined sticklebacks (Gasterosteus aculeatus are more sensitive to red during summer than winter, which may be related to the need to detect the red breeding colour of males. This study aimed to determine whether this change of red light sensitivity is specifically related to reproductive physiology. The mRNA levels of opsin genes were examined in the retinae of sexually mature and immature fish, as well as in sham-operated males, castrated control males, or castrated males implanted with androgen 11-ketoandrostenedione (11 KA, maintained under stimulatory (L16:D8 or inhibitory (L8:D16 photoperiods. In both sexes, red-sensitive opsin gene (lws mRNA levels were higher in sexually mature than in immature fish. Under L16:D8, lws mRNA levels were higher in intact than in castrated males, and were up-regulated by 11 KA treatment in castrated males. Moreover, electroretinogram data confirmed that sexual maturation resulted in higher relative red spectral sensitivity. Mature males under L16:D8 were more sensitive to red light than males under L8:D16. Red light sensitivity under L16:D8 was diminished by castration, but increased by 11 KA treatment. Thus, in sexually mature male sticklebacks, androgen is a key factor in enhancing sensitivity to red light via regulation of opsin gene expression. This is the first study to demonstrate that sex hormones can regulate spectral vision sensitivity.

Muscular Strength Is Associated with Higher Intraocular Pressure in Physically Active Males.

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Vera, Jesús; Jiménez, Raimundo; García-Ramos, Amador; Cárdenas, David

2018-02-01

The positive association between intraocular pressure (IOP) and relative maximum force may have relevance for exercise recommendations when IOP is a concern. The relationship between exercise and IOP has been approached in several studies. However, the influence of muscle function on IOP remains underexplored. This study aimed to determine the relationship between the maximal mechanical capabilities of muscles to generate force, velocity, and power with IOP. Sixty-five physically active males participated in this cross-sectional study. Baseline IOP measures were obtained by rebound tonometry, and participants performed an incremental loading test in the ballistic bench press. Baseline IOP showed a strong positive correlation with relative maximum force (r65 = 0.85, P .05). There is a positive association between greater upper-body power and strength with higher baseline IOP, which might have important implications in the management of ocular health and especially in individuals constantly involved in resistance training programs (e.g., military personnel, weightlifters). The possible protective effect of high fitness level on the acute IOP response to strength exercise needs to be addressed in future studies.

Male courtship preferences demonstrate discrimination against allopatric colour morphs in a cichlid fish.

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Zoppoth, P; Koblmüller, S; Sefc, K M

2013-03-01

Whether premating isolation is achieved by male-specific, female-specific or sex-independent assortative preferences often depends on the underlying evolutionary processes. Here we test mate preferences of males presented with females of different allopatric colour variants of the cichlid fish Tropheus sp., a Lake Tanganyika endemic with rich geographical colour pattern variation, in which the strength of sexual isolation varies between populations. We conducted two-way mate choice experiments to compare behaviour of males of a red-bodied morph (population Moliro) towards females from their own population with behaviour towards females from four allopatric populations at different stages of phylogenetic and phenotypic divergence. Males courted same-population females significantly more intensely than females of other populations, and reduced their heteromorphic courtship efforts both with increasing genetic and increasing phenotypic distinctness of the females. In particular, females of a closely related red-bodied population received significantly more courtship than either genetically distinct, similarly coloured females ('Kirschfleck' morph) or genetically related, differently coloured females ('yellow-blotch' morph), both of which were courted similarly. Genetically and phenotypically distinct females (Tropheus polli) were not courted at all. Consistent with previous female-choice experiments, female courtship activity also decreased with increasing genetic distance from the males' population. Given successful experimental and natural introgression between colour morphs and the pervasive allopatry of related variants, we consider it unlikely that assortative preferences of both sexes were driven by direct selection during periods of secondary contact or, in turn, drove colour pattern differentiation in allopatry. Rather, we suggest that sexual isolation evolved as by-product of allopatric divergence. © 2012 The Authors. Journal of Evolutionary Biology © 2012

Appetitive Aggression in Women: Comparing Male and Female War Combatants

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Danie eMeyer-Parlapanis

2016-01-01

Full Text Available Appetitive aggression refers to positive feelings being associated with the perpetration of violent behavior and has been shown to provide resilience against the development of PTSD in combatants returning from the battlefield. Until this point, appetitive aggression has been primarily researched in males. This study investigates appetitive aggression in females. Female and male combatants and civilians from Burundi were assessed for levels of appetitive aggression. In contrast to non-combatants, no sex difference in appetitive aggression could be detected for combatants. Furthermore, each of the female and male combatant groups displayed substantially higher levels of appetitive aggression than each of the male and female civilian control groups. This study demonstrates that in violent contexts, such as armed conflict, in which individuals perpetrate numerous aggressive acts against others, the likelihood for an experience of appetitive aggression increases- regardless of whether the individuals are male or female.

True polyploid meiosis in the human male.

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Pearson, Peter L; Madan, Kamlesh

2018-05-21

Polyploidy does not usually occur in germinal cells of mammals and other higher vertebrates. We describe a unique example of mosaic autotetraploidy in the meiosis of a human male. Although the original observations were made in the late 1960s, we did not publish them at that time, because we expected to detect further examples that could be described together. However, this did not occur and we have now decided to make the observations available to demonstrate that polyploidy in mammalian male meiosis can arise at a higher frequency than expected by random polyploidization of individual meiotic cells, by either DNA duplication or cell fusion prior to synapsis. This is the first description of a population of primary spermatocytes exhibiting multivalent formation at leptotene /diakinesis in human spermatogenesis, with ring, chain, frying pan and other types of quadrivalents, typical of autotetraploidy. As many of the polyploid configurations showed apoptotic breakdown, it is likely that diploid and/or aneuploid spermatozoa would have rarely or never resulted from this mosaic autotetraploid meiosis.

Empathic Accuracy in Male Adolescents with Conduct Disorder and Higher versus Lower Levels of Callous-Unemotional Traits.

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Martin-Key, N; Brown, T; Fairchild, G

2017-10-01

Adolescents with disruptive behavior disorders are reported to show deficits in empathy and emotion recognition. However, prior studies have mainly used questionnaires to measure empathy or experimental paradigms that are lacking in ecological validity. We used an empathic accuracy (EA) task to study EA, emotion recognition, and affective empathy in 77 male adolescents aged 13-18 years: 37 with Conduct Disorder (CD) and 40 typically-developing controls. The CD sample was divided into higher callous-emotional traits (CD/CU+) and lower callous-unemotional traits (CD/CU-) subgroups using a median split. Participants watched films of actors recalling happy, sad, surprised, angry, disgusted or fearful autobiographical experiences and provided continuous ratings of emotional intensity (assessing EA), as well as naming the emotion (recognition) and reporting the emotion they experienced themselves (affective empathy). The CD and typically-developing groups did not significantly differ in EA and there were also no differences between the CD/CU+ and CD/CU- subgroups. Participants with CD were significantly less accurate than controls in recognizing sadness, fear, and disgust, all ps sadness, fear, and disgust relative to controls, all ps < 0.010, rs ≥ 0.33, whereas the CD/CU+ and CD/CU- subgroups did not differ in affective empathy. These results extend prior research by demonstrating affective empathy and emotion recognition deficits in adolescents with CD using a more ecologically-valid task, and challenge the view that affective empathy deficits are specific to CD/CU+.

Sneaker "jack" males outcompete dominant "hooknose" males under sperm competition in Chinook salmon (Oncorhynchus tshawytscha).

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Young, Brent; Conti, David V; Dean, Matthew D

2013-12-01

In a variety of taxa, males deploy alternative reproductive tactics to secure fertilizations. In many species, small "sneaker" males attempt to steal fertilizations while avoiding encounters with larger, more aggressive, dominant males. Sneaker males usually face a number of disadvantages, including reduced access to females and the higher likelihood that upon ejaculation, their sperm face competition from other males. Nevertheless, sneaker males represent an evolutionarily stable strategy under a wide range of conditions. Game theory suggests that sneaker males compensate for these disadvantages by investing disproportionately in spermatogenesis, by producing more sperm per unit body mass (the "fair raffle") and/or by producing higher quality sperm (the "loaded raffle"). Here, we test these models by competing sperm from sneaker "jack" males against sperm from dominant "hooknose" males in Chinook salmon. Using two complementary approaches, we reject the fair raffle in favor of the loaded raffle and estimate that jack males were ∼1.35 times as likely as hooknose males to fertilize eggs under controlled competitive conditions. Interestingly, the direction and magnitude of this skew in paternity shifted according to individual female egg donors, suggesting cryptic female choice could moderate the outcomes of sperm competition in this externally fertilizing species.

Body dissatisfaction and the wish for different silhouette is associated with higher adiposity and fat intake in female ballet dancers than male.

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Da Silva, Camila Lacerda; De Oliveira, Erick Prado; De Sousa, Maysa Vieira; Pimentel, Gustavo D

2016-01-01

It is known that behavioral disorders and altered food intake are linked to ballet dancers. Thus, the aim of the present study was to investigate the body composition, dietetic profile, self-perceived body image and social desirability in professional ballet dancers. This study was conducted from April to October 2010 in athletes screened for nutritional evaluation. Anthropometric, dietary, social desirability and self-perceived body image evaluation were performed to attend the aim of study. We found that ballet dancers are highly trained and eutrophic, although female dancers had higher adiposity and fat intake than male dancers. In addition, it was observed low consumption of calcium, dietary fiber, potassium, magnesium and vitamin A. Moreover, 30% of male ballet dancers have a strong desire for social acceptance. When the body image was evaluated by Body Shape Questionnaire (BSQ), was reported that 40% of the ballet female dancers have of moderate to severe alteration in body image and 20% of male dancers had slight alteration. Furthermore, the Drawings and Silhouettes Scale showed that 80% of male dancers wish to have a smaller or larger silhouette than the current self-perceived and 60% of the female dancers would like to have a silhouette lower than the self-perceive as current. Collectively, our results shown that most of the dancers were eutrophic, but female athletes have higher adiposity and present strong desire for a different shape of current. Furthermore, was found increased fat intake in female group; however, deficiencies in consumption of dietary fiber, calcium, potassium, magnesium and vitamin A were found in both gender.

Sneaker “jack” males outcompete dominant “hooknose” males under sperm competition in Chinook salmon (Oncorhynchus tshawytscha)

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Young, Brent; Conti, David V; Dean, Matthew D

2013-01-01

In a variety of taxa, males deploy alternative reproductive tactics to secure fertilizations. In many species, small “sneaker” males attempt to steal fertilizations while avoiding encounters with larger, more aggressive, dominant males. Sneaker males usually face a number of disadvantages, including reduced access to females and the higher likelihood that upon ejaculation, their sperm face competition from other males. Nevertheless, sneaker males represent an evolutionarily stable strategy un...

Effect of Amphetamine on Adult Male and Female Rats Prenatally Exposed to Methamphetamine

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Romana Šlamberová

2014-01-01

Full Text Available The aim of the present study was to examine the cross-sensitization induced by prenatal methamphetamine (MA exposure to adult amphetamine (AMP treatment in male and female rats. Rat mothers received a daily injection of MA (5 mg/kg or saline throughout the gestation period. Adult male and female offspring (prenatally MA- or saline-exposed were administered with AMP (5 mg/kg or saline (1 ml/kg in adulthood. Behaviour in unknown environment was examined in open field test (Laboras, active drug-seeking behaviour in conditioned place preference test (CPP, spatial memory in the Morris water maze (MWM, and levels of corticosterone (CORT were analyzed by enzyme immunoassay (EIA. Our data demonstrate that in Laboras test, AMP treatment in adulthood increased general locomotion (time and distance travelled regardless of the prenatal exposure and sex, while AMP increased exploratory activity (rearing only in prenatally MA-exposed animals. AMP induced sensitization only in male rats, but not in females when tested drug-seeking behaviour in the CPP test. In the spatial memory MWM test, AMP worsened the performance only in females, but not in males. On the other hand, males swam faster after chronic AMP treatment regardless of the prenatal drug exposure. EIA analysis of CORT levels demonstrated higher level in females in all measurement settings. In males, prenatal MA exposure and chronic adult AMP treatment decreased CORT levels. Thus, our data demonstrated that adult AMP treatment affects behaviour of adult rats, their spatial memory and stress response in sex-specific manner. The effect is also influenced by prenatal drug exposure.

Sneaker “jack” males outcompete dominant “hooknose” males under sperm competition in Chinook salmon (Oncorhynchus tshawytscha)

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Young, Brent; Conti, David V; Dean, Matthew D

2013-01-01

In a variety of taxa, males deploy alternative reproductive tactics to secure fertilizations. In many species, small “sneaker” males attempt to steal fertilizations while avoiding encounters with larger, more aggressive, dominant males. Sneaker males usually face a number of disadvantages, including reduced access to females and the higher likelihood that upon ejaculation, their sperm face competition from other males. Nevertheless, sneaker males represent an evolutionarily stable strategy under a wide range of conditions. Game theory suggests that sneaker males compensate for these disadvantages by investing disproportionately in spermatogenesis, by producing more sperm per unit body mass (the “fair raffle”) and/or by producing higher quality sperm (the “loaded raffle”). Here, we test these models by competing sperm from sneaker “jack” males against sperm from dominant “hooknose” males in Chinook salmon. Using two complementary approaches, we reject the fair raffle in favor of the loaded raffle and estimate that jack males were ∼1.35 times as likely as hooknose males to fertilize eggs under controlled competitive conditions. Interestingly, the direction and magnitude of this skew in paternity shifted according to individual female egg donors, suggesting cryptic female choice could moderate the outcomes of sperm competition in this externally fertilizing species. PMID:24455130

Male and female runners demonstrate different sagittal plane mechanics as a function of static hamstring flexibility

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D. S. Blaise Williams III

2015-10-01

Full Text Available ABSTRACTBackground:Injuries to runners are common. However, there are many potential contributing factors to injury. While lack of flexibility alone is commonly related to injury, there are clear differences in hamstring flexibility between males and females.Objective: To compare the effect of static hamstring length on sagittal plane mechanics between male and female runners.Method: Forty subjects (30.0±6.4 years participated and were placed in one of 4 groups: flexible males (n=10, inflexible males (n=10, flexible females (n=10, and inflexible females (n=10. All subjects were free of injury at the time of data collection. Three-dimensional kinematics and kinetics were collected while subjects ran over ground across 2 force platforms. Sagittal plane joint angles and moments were calculated at the knee and hip and compared with a 2-way (sex X flexibility ANOVA (α=0.05.Results: Males exhibited greater peak knee extension moment than females (M=2.80±0.47, F=2.48±0.52 Nm/kg*m, p=0.05 and inflexible runners exhibited greater peak knee extension moment than flexible runners (In=2.83±0.56, Fl=2.44±0.51 Nm/kg*m, p=0.01. For hip flexion at initial contact, a significant interaction existed (p<0.05. Flexible females (36.7±7.4º exhibited more hip flexion than inflexible females (27.9±4.6º, p<0.01 and flexible males (30.1±9.5º, p<0.05. No differences existed for knee angle at initial contact, peak knee angle, peak hip angle, or peak hip moment.Conclusion: Hamstring flexibility results in different mechanical profiles in males and females. Flexibility in the hamstrings may result in decreased moments via active or passive tension. These differences may have implications for performance and injury in flexible female runners.

Male and female runners demonstrate different sagittal plane mechanics as a function of static hamstring flexibility.

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Williams, D S Blaise; Welch, Lee M

2015-01-01

Injuries to runners are common. However, there are many potential contributing factors to injury. While lack of flexibility alone is commonly related to injury, there are clear differences in hamstring flexibility between males and females. To compare the effect of static hamstring length on sagittal plane mechanics between male and female runners. Forty subjects (30.0±6.4 years) participated and were placed in one of 4 groups: flexible males (n=10), inflexible males (n=10), flexible females (n=10), and inflexible females (n=10). All subjects were free of injury at the time of data collection. Three-dimensional kinematics and kinetics were collected while subjects ran over ground across 2 force platforms. Sagittal plane joint angles and moments were calculated at the knee and hip and compared with a 2-way (sex X flexibility) ANOVA (α=0.05). Males exhibited greater peak knee extension moment than females (M=2.80±0.47, F=2.48±0.52 Nm/kg*m, p=0.05) and inflexible runners exhibited greater peak knee extension moment than flexible runners (In=2.83±0.56, Fl=2.44±0.51 Nm/kg*m, p=0.01). For hip flexion at initial contact, a significant interaction existed (pHamstring flexibility results in different mechanical profiles in males and females. Flexibility in the hamstrings may result in decreased moments via active or passive tension. These differences may have implications for performance and injury in flexible female runners.

Male and female runners demonstrate different sagittal plane mechanics as a function of static hamstring flexibility

Science.gov (United States)

Williams III, D. S. Blaise; Welch, Lee M.

2015-01-01

ABSTRACT Background: Injuries to runners are common. However, there are many potential contributing factors to injury. While lack of flexibility alone is commonly related to injury, there are clear differences in hamstring flexibility between males and females. Objective: To compare the effect of static hamstring length on sagittal plane mechanics between male and female runners. Method: Forty subjects (30.0±6.4 years) participated and were placed in one of 4 groups: flexible males (n=10), inflexible males (n=10), flexible females (n=10), and inflexible females (n=10). All subjects were free of injury at the time of data collection. Three-dimensional kinematics and kinetics were collected while subjects ran over ground across 2 force platforms. Sagittal plane joint angles and moments were calculated at the knee and hip and compared with a 2-way (sex X flexibility) ANOVA (α=0.05). Results: Males exhibited greater peak knee extension moment than females (M=2.80±0.47, F=2.48±0.52 Nm/kg*m, p=0.05) and inflexible runners exhibited greater peak knee extension moment than flexible runners (In=2.83±0.56, Fl=2.44±0.51 Nm/kg*m, p=0.01). For hip flexion at initial contact, a significant interaction existed (pHamstring flexibility results in different mechanical profiles in males and females. Flexibility in the hamstrings may result in decreased moments via active or passive tension. These differences may have implications for performance and injury in flexible female runners. PMID:26537812

Gonadotropin-Releasing Hormone Modulates Vomeronasal Neuron Response to Male Salamander Pheromone

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Celeste R. Wirsig-Wiechmann

2012-01-01

Full Text Available Electrophysiological studies have shown that gonadotropin-releasing hormone (GnRH modifies chemosensory neurons responses to odors. We have previously demonstrated that male Plethodon shermani pheromone stimulates vomeronasal neurons in the female conspecific. In the present study we used agmatine uptake as a relative measure of the effects of GnRH on this pheromone-induced neural activation of vomeronasal neurons. Whole male pheromone extract containing 3 millimolar agmatine with or without 10 micromolar GnRH was applied to the nasolabial groove of female salamanders for 45 minutes. Immunocytochemical procedures were conducted to visualize and quantify relative agmatine uptake as measured by labeling density of activated vomeronasal neurons. The relative number of labeled neurons did not differ between the two groups: pheromone alone or pheromone-GnRH. However, vomeronasal neurons exposed to pheromone-GnRH collectively demonstrated higher labeling intensity, as a percentage above background (75% as compared with neurons exposed to pheromone alone (63%, P < 0.018. Since the labeling intensity of agmatine within neurons signifies the relative activity levels of the neurons, these results suggest that GnRH increases the response of female vomeronasal neurons to male pheromone.

Low External Workloads Are Related to Higher Injury Risk in Professional Male Basketball Games

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Toni Caparrós, Martí Casals, Álvaro Solana, Javier Peña

2018-06-01

Full Text Available The primary purpose of this study was to identify potential risk factors for sports injuries in professional basketball. An observational retrospective cohort study involving a male professional basketball team, using game tracking data was conducted during three consecutive seasons. Thirty-three professional basketball players took part in this study. A total of 29 time-loss injuries were recorded during regular season games, accounting for 244 total missed games with a mean of 16.26 ± 15.21 per player and season. The tracking data included the following variables: minutes played, physiological load, physiological intensity, mechanical load, mechanical intensity, distance covered, walking maximal speed, maximal speed, sprinting maximal speed, maximal speed, average offensive speed, average defensive speed, level one acceleration, level two acceleration, level three acceleration, level four acceleration, level one deceleration, level two deceleration, level three deceleration, level four deceleration, player efficiency rating and usage percentage. The influence of demographic characteristics, tracking data and performance factors on the risk of injury was investigated using multivariate analysis with their incidence rate ratios (IRRs. Athletes with less or equal than 3 decelerations per game (IRR, 4.36; 95% CI, 1.78-10.6 and those running less or equal than 1.3 miles per game (lower workload (IRR, 6.42 ; 95% CI, 2.52-16.3 had a higher risk of injury during games (p < 0.01 in both cases. Therefore, unloaded players have a higher risk of injury. Adequate management of training loads might be a relevant factor to reduce the likelihood of injury according to individual profiles.

Frogs Call at a Higher Pitch in Traffic Noise

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Kirsten M. Parris

2009-06-01

Full Text Available Male frogs call to attract females for mating and to defend territories from rival males. Female frogs of some species prefer lower-pitched calls, which indicate larger, more experienced males. Acoustic interference occurs when background noise reduces the active distance or the distance over which an acoustic signal can be detected. Birds are known to call at a higher pitch or frequency in urban noise, decreasing acoustic interference from low-frequency noise. Using Bayesian linear regression, we investigated the effect of traffic noise on the pitch of advertisement calls in two species of frogs, the southern brown tree frog (Litoria ewingii and the common eastern froglet (Crinia signifera. We found evidence that L. ewingii calls at a higher pitch in traffic noise, with an average increase in dominant frequency of 4.1 Hz/dB of traffic noise, and a total effect size of 123 Hz. This frequency shift is smaller than that observed in birds, but is still large enough to be detected by conspecific frogs and confer a significant benefit to the caller. Mathematical modelling predicted a 24% increase in the active distance of a L. ewingii call in traffic noise with a frequency shift of this size. Crinia signifera may also call at a higher pitch in traffic noise, but more data are required to be confident of this effect. Because frog calls are innate rather than learned, the frequency shift demonstrated by L. ewingii may represent an evolutionary adaptation to noisy conditions. The phenomenon of frogs calling at a higher pitch in traffic noise could therefore constitute an intriguing trade-off between audibility and attractiveness to potential mates.

[Old gender patterns still used when physicians are pictured in medical journals. Male physicians are portrayed as active leaders, women physicians as listening, compassionate].

Science.gov (United States)

Eriksson, Bodil; Johansson, Eva E

As a part of a medical student' s research project on medical socialisation, the 2002 issue of two Swedish medicaljournals, Läkartidningen and Moderna Läkare, were scrutinized regarding how male and female physicians were represented on pictures. The outward façade was mostly male; 87% of portrays of editorials pictured a man, 81% of career announcements displayed men. Authors of articles and chroniclers more often presented a female face (55%). Photos in reports showed around 60% men and 40 % women, both regarding area and number of photos. These shares corresponded well to the actual share of male and female physicians in Sweden. The content analysis of pictures, however, demonstrated gender features: men were to a much higher degree focused in leading, demonstrating and speaker positions, while women to a higher degree were portrayed as taking part in consultations or caring activities.

Grooming reciprocity in male Tibetan macaques.

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Xia, Dong-Po; Li, Jin-Hua; Garber, Paul A; Matheson, Megan D; Sun, Bing-Hua; Zhu, Yong

2013-10-01

In several primate species, adult males are reported to compete for access to reproductive partners as well as forming affiliative and cohesive social bonds based on the exchange of goods or services. We hypothesized that among a broad set of fitness-maximizing strategies, grooming can be used by individual adult males to enhance social relationships through reciprocity and/or through the interchange of grooming for a different but equivalent good or service. We used focal animal sampling and continuously recorded dyadic grooming and agonistic interactions to test a series of predictions regarding male social interactions in a free-ranging group of Tibetan macaques (Macaca thibetana) at Huangshan, China. During the non-mating season or between males of similar rank throughout the year, grooming effort given was matched by grooming effort received. However, lower ranking males groomed higher ranking males at a greater rate and/or for a longer duration during both the mating and non-mating periods. We found that higher ranking males directed less aggression towards males with whom they formed a frequent grooming partnership, indicating that grooming received was interchanged for increased social tolerance. These data suggest that individual male Tibetan macaques employ alternative social strategies associated with grooming reciprocity or interchange depending on dominance rank and rates of aggression, and highlight the importance of both biological markets and grooming reciprocity as behavioral mechanisms used by resident adult males to form and maintain affiliative social bonds. © 2013 Wiley Periodicals, Inc.

Rock Sparrow Song Reflects Male Age and Reproductive Success

DEFF Research Database (Denmark)

Nemeth, Erwin; Kempenaers, Bart; Matessi, Giuliano

2012-01-01

The evolution of mating signals is closely linked to sexual selection. Acoustic ornaments are often used as secondary sexual traits that signal the quality of the signaller. Here we show that song performance reflects age and reproductive success in the rock sparrow (Petronia petronia...... nests. Older males could be distinguished from yearlings by singing at lower rate and higher amplitudes. Our findings suggest that song rate may be used as a signal of age and together with song pitch as a signal of reproductive success in this species. Alternatively, younger and less successful males...... success. Males with higher breeding success sang at a lower rate and with a higher maximum frequency. We found also that older males gained more extra-pair young and had a higher overall breeding success, although they also differed almost significantly by having a higher loss of paternity in their own...

Blood cadmium levels are associated with a decline in lung function in males

International Nuclear Information System (INIS)

Oh, Chang-Mo; Oh, In-Hwan; Lee, Jong-Keun; Park, Yoon Hyung; Choe, Bong-Keun; Yoon, Tai-Young; Choi, Joong-Myung

2014-01-01

Background: Cadmium exposure was found to cause a decline in lung function among the general population, but these findings were limited to smokers and gender differences were not explored. Objectives: To examine the relationship between cadmium and chronic obstructive pulmonary disease (COPD) according to gender and smoking status in Korea. Methods: Cross-sectional data from the Korean National Health and Nutrition Examination Survey from 2008 to 2011 were analyzed. COPD was defined by a pre-bronchodilator forced expiratory volume in 1 s divided by forced vital capacity of <0.70. A logistic regression model was used to elucidate the association between blood cadmium levels and COPD according to gender and smoking status. Results: Among 3861 eligible participants, 3622 were included in the analysis. The prevalence of COPD demonstrated an increasing trend in males (P for trend<0.001), but not in females (P for trend=0.67). After adjusting for covariates, a higher blood cadmium level, but within the normal range, was associated with COPD in males, including those who had never-smoked (P for trend <0.001 and P for trend=0.008). However, a higher blood cadmium level was not significantly associated with COPD in females, including those who had never smoked (P for trend=0.39 and P for trend=0.43). Conclusions: A higher blood cadmium level, within the normal range, was associated with COPD in males, including those who had never smoked. However, there was no significant association between blood cadmium levels and COPD in females. - Highlights: • Elevated blood cadmium level is associated with chronic obstructive pulmonary disease in male. • This association can be seen even in never smoked male. • However, this association is present only in male, but not in female

Blood cadmium levels are associated with a decline in lung function in males

Energy Technology Data Exchange (ETDEWEB)

Oh, Chang-Mo [Department of Preventive Medicine, School of Medicine, Kyung Hee University, Seoul 130-701 (Korea, Republic of); The Korea Central Cancer Registry, National Cancer Center, Goyang (Korea, Republic of); Oh, In-Hwan; Lee, Jong-Keun [Department of Preventive Medicine, School of Medicine, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Park, Yoon Hyung [Departments of Preventive Medicine, School of Medicine, Soonchunhyang University, Seoul (Korea, Republic of); Choe, Bong-Keun; Yoon, Tai-Young [Department of Preventive Medicine, School of Medicine, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Choi, Joong-Myung, E-mail: jmchoi@khu.ac.kr [Department of Preventive Medicine, School of Medicine, Kyung Hee University, Seoul 130-701 (Korea, Republic of)

2014-07-15

Background: Cadmium exposure was found to cause a decline in lung function among the general population, but these findings were limited to smokers and gender differences were not explored. Objectives: To examine the relationship between cadmium and chronic obstructive pulmonary disease (COPD) according to gender and smoking status in Korea. Methods: Cross-sectional data from the Korean National Health and Nutrition Examination Survey from 2008 to 2011 were analyzed. COPD was defined by a pre-bronchodilator forced expiratory volume in 1 s divided by forced vital capacity of <0.70. A logistic regression model was used to elucidate the association between blood cadmium levels and COPD according to gender and smoking status. Results: Among 3861 eligible participants, 3622 were included in the analysis. The prevalence of COPD demonstrated an increasing trend in males (P for trend<0.001), but not in females (P for trend=0.67). After adjusting for covariates, a higher blood cadmium level, but within the normal range, was associated with COPD in males, including those who had never-smoked (P for trend <0.001 and P for trend=0.008). However, a higher blood cadmium level was not significantly associated with COPD in females, including those who had never smoked (P for trend=0.39 and P for trend=0.43). Conclusions: A higher blood cadmium level, within the normal range, was associated with COPD in males, including those who had never smoked. However, there was no significant association between blood cadmium levels and COPD in females. - Highlights: • Elevated blood cadmium level is associated with chronic obstructive pulmonary disease in male. • This association can be seen even in never smoked male. • However, this association is present only in male, but not in female.

Long-Term Anabolic Androgenic Steroid Use Is Associated with Increased Atrial Electromechanical Delay in Male Bodybuilders

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Mustafa Akçakoyun

2014-01-01

Full Text Available We investigated the effect of long-term supraphysiologic doses of anabolic androgenic steroids (AAS on atrial electromechanical delay (AEMD in male bodybuilders. We clearly demonstrated that long-term consumption of supraphysiologic doses of AAS is associated with higher values of inter- and intra-AEMD in healthy young bodybuilders.

Male yawning is more contagious than female yawning among chimpanzees (Pan troglodytes.

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Jorg J M Massen

Full Text Available Yawn contagion is not restricted to humans and has also been reported for several non-human animal species, including chimpanzees (Pan troglodytes. Contagious yawning may lead to synchronisation of behaviour. However, the function of contagious yawning is relatively understudied. In this study, we investigated the function of contagious yawning by focusing on two types of signal providers: close social associates and leaders. We provided a captive chimpanzee colony with videos of all individuals of their own group that were either yawning, or at rest. Consistent with other studies, we demonstrated that yawning is contagious for chimpanzees, yet we did not find any effect of relationship quality on yawn contagion. However, we show that yawn contagion is significantly higher when the video model is a yawning male than when the video model was a yawning female, and that this effect is most apparent among males. As males are dominant in chimpanzee societies, male signals may be more relevant to the rest of the group than female signals. Moreover, since chimpanzees form male-bonded societies, male signals are especially relevant for other males. Therefore, we suggest that the sex-differences of yawning contagion among chimpanzees reflect the function of yawning in the synchronisation of behaviour.

Demand for male contraception.

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Dorman, Emily; Bishai, David

2012-10-01

The biological basis for male contraception was established decades ago, but despite promising breakthroughs and the financial burden men increasingly bear due to better enforcement of child support policies, no viable alternative to the condom has been brought to market. Men who wish to control their fertility must rely on female compliance with contraceptives, barrier methods, vasectomy or abstinence. Over the last 10 years, the pharmaceutical industry has abandoned most of its investment in the field, leaving only nonprofit organisations and public entities pursuing male contraception. Leading explanations are uncertain forecasts of market demand pitted against the need for critical investments to demonstrate the safety of existing candidate products. This paper explores the developments and challenges in male contraception research. We produce preliminary estimates of potential market size for a safe and effective male contraceptive based on available data to estimate the potential market for a novel male method.

Correlates of Male Condom Use Skills among High-Risk Women in South Africa

Science.gov (United States)

Browne, Felicia A.; Wechsberg, Wendee M.; Bowling, J. Michael; Luseno, Winnie K.

2014-01-01

This exploratory study examines the performance of 295 South African women—who recently traded sex for goods or had unprotected sex—on a male condom use mastery index. Bivariate and multivariate logistic regression analyses were conducted to determine whether age, marital status, highest education obtained, male condom use at first penetrative sex, receiving prior demonstration of male condom use, recent sexually transmitted infection (STI) symptoms, and recently trading sex were significantly associated with index scores. Adjusted odds ratios indicated that age and STI symptoms were negatively associated with condom skills; women who were older and had a higher number of recent STI symptoms were more likely to have lower scores. Furthermore, participants executed, on average, approximately one-third of condom use steps correctly. These findings suggest a need for increased behavioral skills training for women engaging in sexual risk behaviors because many lack the skills required to use a male condom properly. PMID:21660835

Social cliques in male northern muriquis Brachyteles hypoxanthus

Institute of Scientific and Technical Information of China (English)

Marcos TOKUDA; Jean P. BOUBLI; Patrícia IZAR; Karen B. STRIER

2012-01-01

Analyses of spatial relationships and social interactions provide insights into the social structure of animal societies and the ways in which social preferences among and between dyads affect higher order social relationships.In this paper we describe the patterns of spatial associations and social interactions among adult male northern muriquis in order to evaluate the dynamics of their social networks above the dyadic levels.Systematic observations were made on the 17 adult males present in a multi-male/multi-female group from April 2004 through February 2005,and in July 2005.Analyses of their spatial relationships identified two distinct male cliques; some adult males (called "N" males) were more connected to the females and immatures than other adult males ("MU" males),which were more connected to one another.Affiliative interactions were significantly higher among dyads belonging to the same clique than to different cliques.Although frequencies of dyadic agonistic interactions were similarly low among individuals within and between cliques,MU males appeared to be subordinate to N males.Nonetheless,there were no significant differences in the copulation rates estimated for MU males and N males.Mutual benefits of cooperation between MU and N cliques in intergroup encounters might explain their ongoing associations in the same mixed-sex group [Current Zoology 58 (2):342-352,2012].

Brain and gonadal aromatase activity and steroid hormone levels in female and polymorphic males of the peacock blenny Salaria pavo.

Science.gov (United States)

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

2008-11-01

In the peacock blenny Salaria pavo large males with well-developed secondary sexual characters establish nests and attract females while small "sneaker" males mimic female sexual displays in order to approach the nests of larger males and parasitically fertilize eggs. These alternative reproductive tactics are sequential, as sneakers irreversibly switch into nesting males. This transition involves major morphologic and behavioral changes and is likely to be mediated by hormones. This study focuses on the role of aromatase, an enzyme that catalyses the conversion of androgens into estrogens, in the regulation of male sexual polymorphism in S. pavo. For this, sex steroid plasma levels and aromatase activity (AA) in gonads, whole brain and brain macroareas were determined in sneakers, transitional males (i.e. sneakers undergoing the transition into nesting males), nesting males and females collected in the field. AA was much higher in ovarian tissue than in testicular tissue and accordingly circulating estradiol levels were highest in females. This supports the view that elevated AA and estradiol levels are associated with the development of a functional ovary. Transitional males are in a non-reproductive phase and had underdeveloped testes when compared with sneakers and nesting males. Testicular AA was approximately 10 times higher in transitional males when compared with sneakers and nesting males, suggesting high AA has a suppressive effect on testicular development. Nesting males had significantly higher plasma levels of both testosterone (T) and 11-ketotestosterone when compared with the other male morphs and previous studies demonstrated that these androgens suppress female-like displays in sneakers. In the brain, AA was highest in macroareas presumably containing hypothalamic nuclei traditionally associated with the regulation of reproductive behaviors. Overall, females presented the highest levels of brain AA. In male morphs AA increased from sneakers, to

Demonstrating the Impact of a Distributed Leadership Approach in Higher Education

Science.gov (United States)

Jones, Sandra; Harvey, Marina; Hamilton, Jillian; Bevacqua, John; Egea, Kathy; McKenzie, Jo

2017-01-01

Higher education is under pressure to advance from a singular focus on assessment of outputs (measurements) to encompass the impact (influence) of initiatives across all aspects of academic endeavour (research, learning and teaching, and leadership). This paper focuses on the implications of this shift for leadership in higher education.…

Differences in personality traits between male-to-female and female-to-male gender identity disorder subjects.

Science.gov (United States)

Miyajima, Eiichi; Taira, Naoki; Koda, Munenaga; Kondo, Tsuyoshi

2014-12-15

The present study aimed to investigate differences in personality traits among male-to-female (MtF), female-to-male (FtM) gender identity disorder (GID) subjects and non-transsexual male (M) and female (F) controls. Subjects were 72 MtF and 187 FtM GID subjects without psychiatric comorbidities together with 184 male and 159 female non-transsexual controls. Personality traits were assessed using a short version of the Temperament and Character Inventory (TCI-125). Group comparisons were made by two-way ANOVA. Statistical significances were observed as follows: 1) lower novelty seeking in FtM than in M or MtF, 2) higher reward dependence in FtM than in M, 3) higher cooperativeness in FtM than in M or MtF, 4) the highest self-transcendence in MtF among all the groups. The highest self-transcendence in MtF subjects may reflect their vulnerable identity and constrained adaptation to society as the minority. Nevertheless, higher reward dependence and cooperativeness in FtM subjects can be related to more determined motivation for the treatments of GID and might promise better social functioning and adjustment than MtF subjects. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

The vibrational signals that male fiddler crabs ( Uca lactea) use to attract females into their burrows

Science.gov (United States)

Takeshita, Fumio; Murai, Minoru

2016-06-01

In some fiddler crab species, males emit vibrations from their burrows to mate-searching females after they have attracted a female to the burrow entrance using a waving display. Although the vibrations are considered acoustic signals to induce mating, it has not been demonstrated whether the vibrations attract the females into the burrow and, consequently, influence females' mating decisions. We investigated the structures and patterns of the vibrations using a dummy female and demonstrated experimentally a female preference for male vibrations in Uca lactea in the field. The acoustic signals consisted of repetitions of pulses. The dominant frequency of the pulses decreased with male carapace width. The pulse length decreased slightly with an increasing number of vibrational repetitions, and the pulse interval increased with increasing repetitions. These factors imply that the vibrations convey information on male characteristics, such as body size and stamina. In the experiment on female mate choice, the females significantly preferred males with higher pulse repetition rates when they were positioned at the entrance of the burrow, indicating that the females use the male vibrational signals to decide whether to enter the burrow. However, females showed no preference for the vibrations once they were inside a burrow, i.e., whether they decided to copulate, suggesting that the vibrations do not independently affect a female's final decision of mate choice. The vibrations inside the burrow might influence a female's decision by interaction with other male traits such as the burrow structure.

Will male advertisement be a reliable indicator of paternal care, if offspring survival depends on male care?

Science.gov (United States)

Kelly, Natasha B; Alonzo, Suzanne H

2009-09-07

Existing theory predicts that male signalling can be an unreliable indicator of paternal care, but assumes that males with high levels of mating success can have high current reproductive success, without providing any parental care. As a result, this theory does not hold for the many species where offspring survival depends on male parental care. We modelled male allocation of resources between advertisement and care for species with male care where males vary in quality, and the effect of care and advertisement on male fitness is multiplicative rather than additive. Our model predicts that males will allocate proportionally more of their resources to whichever trait (advertisement or paternal care) is more fitness limiting. In contrast to previous theory, we find that male advertisement is always a reliable indicator of paternal care and male phenotypic quality (e.g. males with higher levels of advertisement never allocate less to care than males with lower levels of advertisement). Our model shows that the predicted pattern of male allocation and the reliability of male signalling depend very strongly on whether paternal care is assumed to be necessary for offspring survival and how male care affects offspring survival and male fitness.

Social cliques in male northern muriquis Brachyteles hypoxanthus

Directory of Open Access Journals (Sweden)

Marcos TOKUDA, Jean P. BOUBLI, Patrícia IZAR, Karen B. STRIER

2012-04-01

Full Text Available Analyses of spatial relationships and social interactions provide insights into the social structure of animal societies and the ways in which social preferences among and between dyads affect higher order social relationships. In this paper we describe the patterns of spatial associations and social interactions among adult male northern muriquis in order to evaluate the dynamics of their social networks above the dyadic levels. Systematic observations were made on the 17 adult males present in a multi-male/multi-female group from April 2004 through February 2005, and in July 2005. Analyses of their spatial relationships identified two distinct male cliques; some adult males (called “N” males were more connected to the females and immatures than other adult males (“MU” males, which were more connected to one another. Affiliative interactions were significantly higher among dyads belonging to the same clique than to different cliques. Although frequencies of dyadic agonistic interactions were similarly low among individuals within and between cliques, MU males appeared to be subordinate to N males. Nonetheless, there were no significant differences in the copulation rates estimated for MU males and N males. Mutual benefits of cooperation between MU and N cliques in intergroup encounters might explain their ongoing associations in the same mixed-sex group [Current Zoology 58 (2: 342-352, 2012].

Sexy sons from re-mating do not recoup the direct costs of harmful male interactions in the Drosophila melanogaster laboratory model system.

Science.gov (United States)

Orteiza, N; Linder, J E; Rice, W R

2005-09-01

The empirical foundation for sexual conflict theory is the data from many different taxa demonstrating that females are harmed while interacting with males. However, the interpretation of this keystone evidence has been challenged because females may more than counterbalance the direct costs of interacting with males by the indirect benefits of obtaining higher quality genes for their offspring. A quantification of this trade-off is critical to resolve the controversy and is presented here. A multi-generation fitness assay in the Drosophila melanogaster laboratory model system was used to quantify both the direct costs to females due to interactions with males and indirect benefits via sexy sons. We specifically focus on the interactions that occur between males and nonvirgin females. In the laboratory environment of our base population, females mate soon after eclosion and store sufficient sperm for their entire lifetime, yet males persistently court these nonvirgin females and frequently succeed in re-mating them. Females may benefit from these interactions despite direct costs to their lifetime fecundity if re-mating allows them to trade-up to mates of higher genetic quality and thereby secure indirect benefits for their offspring. We found that direct costs of interactions between males and nonvirgin females substantially exceeded indirect benefits through sexy sons. These data, in combination with past studies of the good genes route of indirect benefits, demonstrate that inter-sexual interactions drive sexually antagonistic co-evolution in this model system.

Young males have a higher risk of developing schizophrenia: a Danish register study

DEFF Research Database (Denmark)

Thorup, Anne; Waltoft, Berit Lindum; Pedersen, Carsten Bøcker

2007-01-01

-specific incidence rates of schizophrenia for people aged up to 71 years. We also estimated the cumulative incidences.Results. The incidence rates for males significantly exceeded those for females in the age range from 17 to 40 years. By their 72nd birthday, 1.59% of males and 1.17% of females had developed......Background. Gender differences are commonly reported in schizophrenia research, especially with regard to age at onset. Few studies have reported the age- and gender-specific incidence of schizophrenia in people aged up to 71 years, and no studies have reported the cumulative incidence...... of schizophrenia in people aged up to 71 years.Method. Two cohorts were established by linking data from the Danish Civil Registration System (DCRS) with data from the Danish Psychiatric Central Register (DPCR), which covers all incident cases of schizophrenia from 15 to 71 years. We estimated the gender- and age...

Young males have a higher risk of developing schizophrenia: a Danish register study

DEFF Research Database (Denmark)

Thorup, Anne; Waltoft, Berit Lindum; Pedersen, Carsten Bøcker

2007-01-01

of schizophrenia in people aged up to 71 years.Method. Two cohorts were established by linking data from the Danish Civil Registration System (DCRS) with data from the Danish Psychiatric Central Register (DPCR), which covers all incident cases of schizophrenia from 15 to 71 years. We estimated the gender- and age......Background. Gender differences are commonly reported in schizophrenia research, especially with regard to age at onset. Few studies have reported the age- and gender-specific incidence of schizophrenia in people aged up to 71 years, and no studies have reported the cumulative incidence......-specific incidence rates of schizophrenia for people aged up to 71 years. We also estimated the cumulative incidences.Results. The incidence rates for males significantly exceeded those for females in the age range from 17 to 40 years. By their 72nd birthday, 1.59% of males and 1.17% of females had developed...

Male scent-marking pheromone of Bombus ardens ardens (Hymenoptera; Apidae) attracts both conspecific queens and males

Science.gov (United States)

Kubo, Ryohei; Harano, Ken-ichi; Ono, Masato

2017-10-01

To explore the role of the volatiles emitted from male labial gland (LG) of the bumblebee Bombus ardens ardens, we investigated the responses of virgin queens and males to volatiles using a gas chromatography-electroantennographic detector (GC-EAD) system and Y-tube olfactometer. GC-EAD analysis revealed that citronellol, the main compound detected in the male LG, caused clear electrophysiological responses in the antennae of B. a. ardens virgin queens and males although two minor compounds elicited antennal responses when applied in a high concentration. Behavioral tests using a Y-tube olfactometer showed that queens and males were significantly attracted to both LG extracts and citronellol more than to the solvent alone. This is the first study to demonstrate that citronellol as a major compound of male scent-marking pheromone in B. a. ardens functions as a sex attractant for queens. The results also suggest that this compound has another function as a trail marker used by males.

The association between male-biased sex ratio and indicators of stress in red-spotted newts.

Science.gov (United States)

Aspbury, Andrea S; Grayson, Kristine L; Fantaye, Selamawit; Nichols, Ian; Myers-Burton, Miranda; Ortiz-Mangual, Xavier; Gabor, Caitlin R

2017-05-01

In populations with a male-biased operational sex ratio, coercive mating by males can have fitness consequences for females. One component of reduced fitness for females in populations with a male-biased OSR may be greater activation of the stress response, resulting in higher corticosterone release rates (CORT; a glucocorticoid stress hormone in amphibians). We test the hypothesis that a male-biased sex ratio affects female activity and release rates of CORT and testosterone (T) in male and female red-spotted newts (Notophthalmus viridescens). First, we evaluated if chemical cues from a male-biased sex ratio affect activity and CORT release rates in females. We predicted that females exposed to chemical cues of three males would be less active and have higher CORT release rates than those exposed to chemical cues of one male. Second, we measured CORT release rates of red-spotted newts in field enclosures with either a male-biased or a female-biased sex ratio. We predicted that females in the male-biased treatment would have higher CORT and T release rates than those in a female-biased treatment, owing to higher levels of male harassment. We also predicted that males would have higher CORT and T release rates in male-biased treatments due to higher levels of male-male competition. Females were not less active in response to chemical cues from more males over fewer males, but there was a positive relationship between female activity and CORT when they were exposed to the cues of three males. We also found that females, but not males, in the male-biased sex ratio treatment had higher CORT and T release rates than those in the female-biased treatment. Our results support the hypothesis that a male-biased sex ratio leads to a higher stress response, which may underlie the observed decrease in immune function and body condition in previous work exposing female red-spotted newts to a male-biased sex ratio. This study furthers our understanding of the mechanistic basis

Free-ranging male koalas use size-related variation in formant frequencies to assess rival males.

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Benjamin D Charlton

Full Text Available Although the use of formant frequencies in nonhuman animal vocal communication systems has received considerable recent interest, only a few studies have examined the importance of these acoustic cues to body size during intra-sexual competition between males. Here we used playback experiments to present free-ranging male koalas with re-synthesised bellow vocalisations in which the formants were shifted to simulate either a large or a small adult male. We found that male looking responses did not differ according to the size variant condition played back. In contrast, male koalas produced longer bellows and spent more time bellowing when they were presented with playbacks simulating larger rivals. In addition, males were significantly slower to respond to this class of playback stimuli than they were to bellows simulating small males. Our results indicate that male koalas invest more effort into their vocal responses when they are presented with bellows that have lower formants indicative of larger rivals, but also show that males are slower to engage in vocal exchanges with larger males that represent more dangerous rivals. By demonstrating that male koalas use formants to assess rivals during the breeding season we have provided evidence that male-male competition constitutes an important selection pressure for broadcasting and attending to size-related formant information in this species. Further empirical studies should investigate the extent to which the use of formants during intra-sexual competition is widespread throughout mammals.

Higher levels of intrinsic motivation are related to higher levels of class performance for male but not female students.

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Cortright, Ronald N; Lujan, Heidi L; Blumberg, Amanda J; Cox, Julie H; DiCarlo, Stephen E

2013-09-01

Our students are naturally curious, with powerful intrinsic motives to understand their world. Accordingly, we, as teachers, must capitalize on this inherently active and curious nature so that learning becomes a lifelong activity where students take initiative for learning, are skilled in learning, and want to learn new things. Achieving this goal requires an understanding of student attitudes, beliefs, characteristics, and motivations. To achieve this goal, we administered the intrinsic motivation inventory (IMI) to assess our students' interest and enjoyment, perceived choice, and perceived competence while taking our undergraduate exercise physiology class (46 students; 20 female students and 26 male students). The interest and enjoyment subscale is considered the self-reported measure of intrinsic motivation. The perceived choice and perceived competence concepts are theorized to be positive predictors of both self-reported and behavioral measures of intrinsic motivation. Our results documented a significant increase in course grade with an increase in survey score for the interest and enjoyment subscale of the IMI when female and male students were combined. Specifically, each increase in survey score for the interest and enjoyment subscale of the IMI was associated with a significant (P students. These results have implications for both classroom practice and educational reform policies.

Prevalence and acceptability of male circumcision in South Africa ...

African Journals Online (AJOL)

... groups and having heard of the HIV protective effect of male circumcision were significant predictors for male circumcision acceptability, and among women with a non-circumcised sexual partner, Black African and Coloured population groups and higher education were predictors for male circumcision acceptability.

Possible association between serotonin transporter promoter region polymorphism and extremely violent crime in Chinese males.

Science.gov (United States)

Liao, Ding-Lieh; Hong, Chen-Jee; Shih, Hao-Ling; Tsai, Shih-Jen

2004-01-01

The neurotransmitter, serotonin, has been implicated in aggressive behavior. The serotonin transporter (5-HTT), which reuptakes serotonin into the nerve terminal, plays a critical role in the regulation of serotonergic function. Previous western reports have demonstrated that the low-activity short (S) allele of the 5-HTT gene-linked polymorphic-region (5-HTTLPR) polymorphism is associated with aggressive behavior and associated personality traits. In the present study, we investigated this 5-HTTLPR genetic polymorphism in a group of Chinese males who had been convicted for extremely violent crime (n = 135) and a normal control group (n = 111). The proportion of S-allele carriers was significantly higher in the criminal group than in the controls (p = 0.006). A significant association was not demonstrated for the relationship between the 5-HTTLPR polymorphism and antisocial personality disorder, substance abuse or alcohol abuse in the criminal group. Our findings demonstrate that carriage of the low-activity S allele is associated with extremely violent criminal behavior in Chinese males, and suggests that the 5-HTT may be implicated in the mechanisms underlying violent behaviors.

Histopathological changes in Poecilia latipinna male gonad due to Tribulus terrestris administration.

Science.gov (United States)

Kavitha, P; Ramesh, R; Subramanian, P

2012-05-01

Tribulus terrestris is a traditionally known non-toxic aphrodisiac herb for maleness. It was experimented recently to understand the effect and mechanism on mono sex production in Poecilia latipinna. It would help to develop a new eco-friendly way to masculinize P. latipinna, since males have higher commercial value than females. The different concentration (100, 150, 200, 250 and 300 mg/L) of T. terrestris extract and a control were tested for their effect on sex transformation/reversal in P. latipinna by immersing the newly born young ones in the respective concentrations for 2 mo. The obtained results indicate that a dose dependant masculinization is obtained due to T. terrestris administration, which improved the male proportion. Histological results revealed that the testes of fish treated with T. terrestris extract contained all stages of spermatogenesis, clearly demonstrating that the administration of T. terrestris extract to P. latipinna stimulated spermatogenesis. Thus, it is discernible that 0-d-old hatchlings of P. latipinna exposed to T. terrestris extract orient/reverse their sex more towards maleness besides yielding better growth and spermatogenesis which is a mandate for fancy fish industry.

Evolution of male-killer suppression in a natural population.

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Emily A Hornett

2006-09-01

Full Text Available Male-killing bacteria are widespread in arthropods, and can profoundly alter the reproductive biology of their host species. Here we detail the first case of complete suppression of a male killer. The nymphalid butterfly Hypolimnas bolina is infected with a strain of the bacterium Wolbachia, wBol1, which kills male host embryos in Polynesian populations, but does not do so in many areas of Southeast Asia, where both males and female adults are naturally infected, and wBol1-infected females produce a 1:1 sex ratio. We demonstrate that absence of male killing by wBol1 is associated with dominant zygotic suppression of the action of the male killer. Simulations demonstrate host suppressors of male-killer action can spread very rapidly, and historical data indicating the presence of male killing in Southeast Asia in the very recent past suggests suppressor spread has been a very recent occurrence. Thus, male killer/host interactions are much more dynamic than previously recognised, with rapid and dramatic loss of the phenotype. Our results also indicate that suppression can render male killers completely quiescent, leading to the conclusion that some species that do not currently express a male killer may have done so in the past, and thus that more species have had their biology affected by these parasites than previously believed.

Comparison between recreational male Ironman triathletes and marathon runners.

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Gianoli, Daniele; Knechtle, Beat; Knechtle, Patrizia; Barandun, Ursula; Rüst, Christoph Alexander; Rosemann, Thomas

2012-08-01

Recent investigations described a personal best marathon time as a predictor variable for an Ironman race time in recreational male Ironman triathletes. Similarities and differences in anthropometry and training were investigated between 83 recreational male Ironman triathletes and 81 recreational male marathoners. Ironman triathletes were significantly taller and had a higher body mass and a higher skin-fold thickness of the calf compared to the marathoners. Weekly training volume in hours was higher in Ironman triathletes. In the Ironman triathletes, percent body fat was related to overall race time and both the split time in cycling and running. The weekly swim kilometres were related to the split time in swimming, and the speed in cycling was related to the bike split time. For the marathoners, the calf skin-fold thickness and running speed during training were related to marathon race time. Although personal best marathon time was a predictor of Ironman race time in male triathletes, anthropometric and training characteristics of male marathoners were different from those of male Ironman triathletes, probably due to training of different muscle groups and metabolic endurance beyond marathon running, as the triathletes are also training for high-level performance in swimming and cycling. Future studies should compare Olympic distance triathletes and road cyclists with Ironman triathletes.

Adolescent Male Human Papillomavirus Vaccination

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Vivian C. Nanagas MD, MSc

2016-04-01

Full Text Available Objective. To determine male vaccination rates with quadrivalent human papillomavirus vaccine (HPV4 before and after the October 2011 national recommendation to routinely immunize adolescent males. Methods. We reviewed HPV4 dose 1 (HPV4-1 uptake in 292 adolescent males in our urban clinic prior to national recommendations and followed-up for HPV4 series completion rates. After national recommendation, 248 urban clinic and 247 suburban clinic males were reviewed for HPV4-1 uptake. Factors associated with HPV4-1 refusal were determined with multiple logistic regression. Results. Of the initial 292 males, 78% received HPV4-1 and 38% received the 3-dose series. After recommendation, HPV4-1 uptake was 59% and 7% in urban and suburban clinics, respectively. Variables associated with HPV4-1 uptake/refusal included time period, race, type of insurance, and receipt of concurrent vaccines. Conclusions. HPV4-1 vaccination rates in our urban clinic were high before and after routine HPV vaccine recommendations for adolescent males. Our vaccination rates were much higher than in a suburban practice.

Female medical students are estimated to have a higher risk for developing eating disorders than male medical students.

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Dissing, Agnete Skovlund; Bak, Nanna Hasle; Pedersen, Laura Erna Toftegaard; Petersson, Birgit H

2011-01-01

Studies show that university students are at risk for eating disorders. However, risk behaviour has not been studied among Danish medical students, nor have the gender differences in risk behaviour been described in a Danish context. All first-year medical students (n = 979) received a questionnaire related to body perception, exercise habits, eating habits, height and weight in the fall of 2006 and 2007. The response rate was 57% (n = 561). The gender distribution of the study population was 71.8% females and 28.2% males and the average age was 21.5 years. More males (89.8%) than females (73.1%) were satisfied with their body and more females (34.8%) than males (10.9%) felt too fat. More females (42.7%) than males (19.9%) felt guilty when eating unhealthy food. 2.3% (all females) claimed to feel anxiety when they were about to eat. More males (48.4%) than females (28.6%) stated that they could not keep themselves from exercising. 13.5% of the underweight females (body mass index eating disorders than male students. Future research in this area should address the causes of such behaviour.

Testosterone increases circulating dehydroepiandrosterone sulfate levels in the male rhesus macaque

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Krystina eSorwell

2014-06-01

Full Text Available The adrenal steroid dehydroepiandrosterone (DHEA and its sulfate (DHEAS are two of the most abundant hormones in the human circulation. Furthermore, they are released in a circadian pattern and show a marked age-associated decline. Adult levels of DHEA and DHEAS are significantly higher in males than in females, but the reason for this sexual dimorphism is unclear. In the present study, we administered supplementary androgens (DHEA, testosterone and 5α-dihydrotestosterone [DHT] to aged male rhesus macaques (Macaca mulatta. While this paradigm increased circulating DHEAS immediately after DHEA administration, an increase was also observed following either testosterone or DHT administration, resulting in hormonal profile resembling levels observed in young males in terms of both amplitude and circadian pattern. This stimulatory effect was limited to DHEAS, as an increase in circulating cortisol was not observed. Taken together, these data demonstrate an influence of the hypothalamo-pituitary-testicular axis on adrenal function in males, possibly by sensitizing the zona reticularis to the stimulating action of adrenocorticopic hormone. This represents a plausible mechanism to explain sex differences in circulating DHEA and DHEAS levels, and may have important implications in the development of hormone therapies designed for elderly men and women.

Perceptions of Credibility of Male and Female Syndicated Political Columnists.

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Andsager, Julie L.

1990-01-01

Examines perceptions of the credibility of male and female syndicated political columnists. Finds that college students exhibited little prejudice against female versus male bylines in political interpretive columns. Finds a small tendency for male readers to evaluate male bylines higher in stereotypical ways, but female readers do not do this.…

New Insights Into the Role of Estrogens in Male Fertility Based on Findings in Aromatase-Deficient Zebrafish.

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Tang, Haipei; Chen, Yu; Liu, Yun; Yin, Yike; Li, Gaofei; Guo, Yin; Liu, Xiaochun; Lin, Haoran

2017-09-01

It has been demonstrated that estrogens are indispensable for male fertility in mammals. Aromatase (encoded by CYP19) catalyzes the final step of estradiol biosynthesis. However, less is known about the role of aromatase in male fertility in nonmammalian species. Fish aromatase is encoded by two separate genes: the gonad-specific cyp19a1a and the brain-specific cyp19a1b. In a recent study, we used transcription activatorlike effector nucleases to systematically generate cyp19a1a and cyp19a1b mutant lines and a cyp19a1a;cyp19a1b double-mutant line in zebrafish and demonstrated that cyp19a1a was indispensable for sex differentiation. In this study, we focused on male fertility in these aromatase-deficient zebrafish. Our results showed that all aromatase-deficient male fish had normal fertility even at 1 year after fertilization. Interestingly, we observed more spermatozoa in the cyp19a1a and double-mutant males than in the wild-type and cyp19a1b mutant males. The whole-body androgen levels, follicle-stimulating hormone β and luteinizing hormone β protein levels in the pituitary, and transcript levels of genes known to be involved in spermatogenesis and steroidogenesis in the testes were significantly higher in the cyp19a1a mutant and aromatase double-mutant males than in the wild-type and cyp19a1b mutant males. These results might explain why more spermatozoa were observed in these fish. Collectively, our findings indicate that estrogens are not needed to achieve and maintain normal fertility in male zebrafish. This finding challenges the traditional view that estrogens are indispensable for male fertility. Copyright © 2017 Endocrine Society.

Advances in Male Contraception

Science.gov (United States)

Page, Stephanie T.; Amory, John K.; Bremner, William J.

2008-01-01

Despite significant advances in contraceptive options for women over the last 50 yr, world population continues to grow rapidly. Scientists and activists alike point to the devastating environmental impacts that population pressures have caused, including global warming from the developed world and hunger and disease in less developed areas. Moreover, almost half of all pregnancies are still unwanted or unplanned. Clearly, there is a need for expanded, reversible, contraceptive options. Multicultural surveys demonstrate the willingness of men to participate in contraception and their female partners to trust them to do so. Notwithstanding their paucity of options, male methods including vasectomy and condoms account for almost one third of contraceptive use in the United States and other countries. Recent international clinical research efforts have demonstrated high efficacy rates (90–95%) for hormonally based male contraceptives. Current barriers to expanded use include limited delivery methods and perceived regulatory obstacles, which stymie introduction to the marketplace. However, advances in oral and injectable androgen delivery are cause for optimism that these hurdles may be overcome. Nonhormonal methods, such as compounds that target sperm motility, are attractive in their theoretical promise of specificity for the reproductive tract. Gene and protein array technologies continue to identify potential targets for this approach. Such nonhormonal agents will likely reach clinical trials in the near future. Great strides have been made in understanding male reproductive physiology; the combined efforts of scientists, clinicians, industry and governmental funding agencies could make an effective, reversible, male contraceptive an option for family planning over the next decade. PMID:18436704

Genetically conditioned male sterility

International Nuclear Information System (INIS)

Gottschalk, W.

1976-01-01

A survey is given of two different types of genetically controlled male sterility in higher plants. 'Functional' male sterility is due to the action of mutated genes causing a misdifferentiation of the growing points in different specific ways. Under the influence of the genes of this group either the stamens or the archespore tissues are not differentiated. In other mutants functionable male germ cells are produced but cannot be used for fertilizing the egg cells because the anthers remain closed or anthers and stigma become spatially separated from each other. Other genes of the group are responsible for the transformation of stamens into carpels, i.e. for a change of the hermaphrodite flower into a unisexually female one. A second type of male sterility is due to the action of ms genes influencing the course of micro-sporogenesis directly. They cause the breakdown of this process in a specific meiotic stage characteristic for each gene of the group. This breakdown is introduced by the degeneration of PMCs, microspores, or pollen grains preventing the production of male germ cells. The female sex organs remain uninfluenced. (author)

Sexy males and choosy females on exploded leks: correlates of male attractiveness in the Little Bustard.

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Jiguet, Frédéric; Bretagnolle, Vincent

2014-03-01

In their choice of mates, females may use alternative tactics, including a comparative assessment of males in a population, using one or several relative preference criteria. Traits involved in female choice should presumably be variable between, but not within males, thus potentially providing reliable cues of male identity and quality for prospecting females. In lekking species, sexual selection is usually intense, and females can freely choose mates. Studying the Little Bustard Tetrax tetrax, a bird with an exploded lek mating system, we first identified male phenotypic traits that showed higher among, than within variation (plumage pattern, display rates and call structure). Among those and other traits (ornaments and their symmetry, body condition, lek spatial organization and territory quality), we identified phenotypic traits that correlated with male attractiveness toward females. At least four phenotypic male traits were correlated with female attraction, i.e. body condition, lek attendance, ornamental symmetry and display rates. Traits related to the initial female attraction on male territory seem to differ from traits related to the decision of females to stay in the territory of attractive males. Copyright © 2014 Elsevier B.V. All rights reserved.

In Iranian female and male adolescents, romantic love is related to hypomania and low depressive symptoms, but also to higher state anxiety.

Science.gov (United States)

Bajoghli, Hafez; Joshaghani, Narges; Gerber, Markus; Mohammadi, Mohammad-Reza; Holsboer-Trachsler, Edith; Brand, Serge

2013-06-01

Experiencing romantic love is important in individual development. Little is known about romantic love among adolescents in non-Western countries. The aim of the present study was to explore romantic love among Iranian male and female adolescents. A total of 201 adolescents (mean age: 17.73 years) took part in the study; of these, 81 indicated they were experiencing romantic love at the time of survey, and 120 indicated they were not in love. Participants answered questionnaires related to affective states (hypomania, depressive symptoms, state and trait anxiety) and exercise, and completed a sleep log for seven consecutive nights. Compared to controls, participants in love displayed favourable hypomania scores, fewer depressive symptoms and increased concentration during the day. However, participants in love also had higher state anxiety scores. Moreover, hypomanic-like stages increased with duration of relationship in female, but not in male participants. The pattern of results suggests a favourable association between being currently in love and emotional and cognitive processes. Sleep, however, seemed unrelated to this specific state.

Change in sex pheromone expression by nutritional shift in male cockroaches

DEFF Research Database (Denmark)

Jensen, Kim; Shearman, Melanie; Rapkin, James

2017-01-01

affected by dietary nutrient composition with higher values on carbohydrate-biased diet, and males had significantly higher and lower levels of consumption, lipid reserves, and sex pheromones when shifted to a carbohydrate-biased and a protein-biased diet, respectively, compared with males maintained...

Patterns of interventions and the effect of coalitions and sociality on male fitness.

Science.gov (United States)

Kulik, Lars; Muniz, Laura; Mundry, Roger; Widdig, Anja

2012-02-01

In group living animals, especially among primates, there is consistent evidence that high-ranking males gain a higher reproductive output than low-ranking males. Primate studies have shown that male coalitions and sociality can impact male fitness; however, it remains unclear whether males could potentially increase their fitness by preferentially supporting and socializing with females. Here we investigate patterns of male interventions and the effect of coalitions and sociality on male fitness in rhesus macaques (Macaca mulatta) with particular focus on male-female interactions. We combined behavioural observations collected on Cayo Santiago with genetic data analysed for male reproductive output and relatedness. Our results revealed that the ten top-ranking males provided the majority of all male support observed. In contrast to other primates, male rhesus macaques mainly formed all-down coalitions suggesting that coalitions are less likely used to enhance male dominance. Males supporting females during and before their likely conception were not more likely to fertilize those females. We also found no evidence that males preferably support their offspring or other close kin. Interestingly, the most important predictor of male support was sociality, since opponents sharing a higher sociality index with a given male were more likely to be supported. Furthermore, a high sociality index of a given male-female dyad resulted in a higher probability of paternity. Overall, our results strengthen the evidence that sociality affects fitness in male primates, but also suggest that in species in which males queue for dominance, it is less likely that males derive fitness benefits from coalitions. © 2011 Blackwell Publishing Ltd.

Relation of cigarette smoking in males of different ages to sex hormone binding globulin and testosterone

International Nuclear Information System (INIS)

El-Nabarawy, F.S.

2002-01-01

The relationship of cigarette smoking, age, total testosterone free testosterone and sex hormone binding globulin (SHBG) were examined by solid phase radioimmunoassay in 90 randomly chosen healthy males of different ages. The serum levels of these hormones were investigated for smokers compared with non-smokers, of the same ages in 3 groups (adolescent males, middle aged males, and old aged males). Results indicated that cigarette smokers showed increased serum levels of testosterone (60.0% higher, P> 0.05), free testosterone (51.0 higher, P > 0.005) in young adolescent males group, testosterone (27.8% higher, P > 0.001), free testosterone (21.3% higher, P > 0.001) in middle aged males group, and testosterone (21.0% higher, P > 0.001), free testosterone (16.8% higher, P > 0.4) in old ages males group. SHBG was calculated as a mean of free and total testosterone in each group. smokers showed higher mean values of SHBG than non-smokers. Age was positively associated with serum SHBG, it was found that SHBG increased by 17.2% from the youngest (> 18 years) to the oldest age (> 65 years)

Quantitative Trait Locus Analysis of Mating Behavior and Male Sex Pheromones in Nasonia Wasps

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Wenwen Diao

2016-06-01

Full Text Available A major focus in speciation genetics is to identify the chromosomal regions and genes that reduce hybridization and gene flow. We investigated the genetic architecture of mating behavior in the parasitoid wasp species pair Nasonia giraulti and Nasonia oneida that exhibit strong prezygotic isolation. Behavioral analysis showed that N. oneida females had consistently higher latency times, and broke off the mating sequence more often in the mounting stage when confronted with N. giraulti males compared with males of their own species. N. oneida males produce a lower quantity of the long-range male sex pheromone (4R,5S-5-hydroxy-4-decanolide (RS-HDL. Crosses between the two species yielded hybrid males with various pheromone quantities, and these males were used in mating trials with females of either species to measure female mate discrimination rates. A quantitative trait locus (QTL analysis involving 475 recombinant hybrid males (F2, 2148 reciprocally backcrossed females (F3, and a linkage map of 52 equally spaced neutral single nucleotide polymorphism (SNP markers plus SNPs in 40 candidate mating behavior genes revealed four QTL for male pheromone amount, depending on partner species. Our results demonstrate that the RS-HDL pheromone plays a role in the mating system of N. giraulti and N. oneida, but also that additional communication cues are involved in mate choice. No QTL were found for female mate discrimination, which points at a polygenic architecture of female choice with strong environmental influences.

The number of life-history stages does not influence the androgen responsiveness to male-male interactions: sedentary and migratory black redstarts (Phoenicurus ochruros) do not elevate testosterone in response to simulated territorial intrusions.

Science.gov (United States)

Villavicencio, C P; Blas, J; Goymann, W

2014-09-01

High plasma levels of testosterone at the beginning of the breeding season adjust male physiology for mating and promote territorial behavior in birds. Conversely intra-sexual competition may elicit a temporary increase in circulating testosterone. Male black redstarts (Phoenicurus ochruros) from migratory populations show the expected increase in baseline testosterone during early breeding, but circulating testosterone levels do not change in response to male-male interactions. Because sedentary populations express fewer life-history stages they may be more flexible in timing of life-history stages and more responsive to environmental modulation of hormone concentrations. Therefore, we tested whether the androgen responsiveness to male-male interactions differs between migratory (6 life-history stages) and sedentary black redstarts (3 life-history stages) during early breeding, predicting that in contrast to migratory birds, sedentary birds would modulate testosterone in response to simulated territorial intrusions (STI). In contrast to our prediction, sedentary males did not modulate post-capture testosterone levels in response to simulated territorial intrusions. Males of both populations increased testosterone after an injection of gonadotropin releasing hormone (GnRH), demonstrating that they were capable of increasing testosterone. Interestingly, in sedentary males the GnRH injection elicited a higher testosterone response in STI males than in control males. The two populations did not differ in their behavioral response to the STIs, except that sedentary males spent less time close to the decoy. In combination with previous data from black redstarts and other socially monogamous and biparental birds our current study adds to the growing evidence that current theory regarding hormone-behavior relationship needs to be refined. Copyright © 2014 Elsevier Inc. All rights reserved.

Early-Life Social Isolation Influences Mouse Ultrasonic Vocalizations during Male-Male Social Encounters.

Science.gov (United States)

Keesom, Sarah M; Finton, Caitlyn J; Sell, Gabrielle L; Hurley, Laura M

2017-01-01

Early-life social isolation has profound effects on adult social competence. This is often expressed as increased aggression or inappropriate displays of courtship-related behaviors. The social incompetence exhibited by isolated animals could be in part due to an altered ability to participate in communicatory exchanges. House mice (Mus musculus) present an excellent model for exploring this idea, because social isolation has a well-established influence on their social behavior, and mice engage in communication via multiple sensory modalities. Here, we tested the prediction that social isolation during early life would influence ultrasonic vocalizations (USVs) emitted by adult male mice during same-sex social encounters. Starting at three weeks of age, male mice were housed individually or in social groups of four males for five weeks, after which they were placed in one of three types of paired social encounters. Pair types consisted of: two individually housed males, two socially housed males, or an individually housed and a socially housed male ("mixed" pairs). Vocal behavior (USVs) and non-vocal behaviors were recorded from these 15-minute social interactions. Pairs of mice consisting of at least one individually housed male emitted more and longer USVs, with a greater proportional use of USVs containing frequency jumps and 50-kHz components. Individually housed males in the mixed social pairs exhibited increased levels of mounting behavior towards the socially housed males. Mounting in these pairs was positively correlated with increased number and duration of USVs as well as increased proportional use of spectrally more complex USVs. These findings demonstrate that USVs are part of the suite of social behaviors influenced by early-life social isolation, and suggest that altered vocal communication following isolation reflects reduced social competence.

Sexy faces in a male paper wasp.

Science.gov (United States)

de Souza, André Rodrigues; Alberto Mourão Júnior, Carlos; do Nascimento, Fabio Santos; Lino-Neto, José

2014-01-01

Sexually selected signals are common in many animals, though little reported in social insects. We investigated the occurrence of male visual signals mediating the dominance relationships among males and female choice of sexual partner in the paper wasp Polistes simillimus. Males have three conspicuous, variable and sexually dimorphic traits: black pigmentation on the head, a pair of yellow abdominal spots and body size differences. By conducting behavioral assays, we found that none of the three visual traits are associated with male-male dominance relationship. However, males with higher proportion of black facial pigmentation and bigger yellow abdominal spots are more likely chosen as sexual partners. Also, after experimentally manipulating the proportion of black pigment on males' face, we found that females may evaluate male facial coloration during the choice of a sexual partner. Thus, the black pigmentation on P. simillimus male's head appears to play a role as a sexually selected visual signal. We suggest that sexual selection is a common force in Polistes and we highlight the importance of this group as a model for the study of visual communication in insects.

Seminal fluid enhances competitiveness of territorial males' sperm in a fish with alternative male reproductive tactics.

Science.gov (United States)

Poli, Federica; Locatello, Lisa; Rasotto, Maria B

2018-05-29

The most common adaptation to sperm competition in males is represented by an increase in the sperm number and/or quality released at mating, to raise their probability of egg fertilization. However, rapidly mounting evidence highlights that seminal fluid may directly influence the competitive fertilization success of a male by affecting either own and/or rival sperm performances. In the black goby, Gobius niger , an external fertilizer with guard-sneaker mating tactics and high sperm competition level, sneaker males' ejaculates contain less seminal fluid and more sperm, that are also of better quality, than those of territorial males. However, territorial males, gain a higher paternity success inside natural nests. Here, we ask whether the seminal fluid can contribute to territorial males' reproductive success by enhancing their sperm performances and/or by decreasing those of sneaker males. Using sperm and seminal fluid manipulation and in vitro fertilization tests, we found that own seminal fluid influences the velocity and fertilization ability of sperm only in territorial males, making them as faster as those of sneakers and with similar fertilization rate. Moreover, both sneaker and territorial males' sperm remain unaffected by the seminal fluid of rival males. Thus, black goby males respond to the different level of sperm competition faced by differently allocating in sperm and non-sperm components of the ejaculate, with sneakers primarily investing in sperm of intrinsic high quality and territorial males relying on the effect of seminal fluid to increase the lower intrinsic quality of their sperm. © 2018. Published by The Company of Biologists Ltd.

Interspecific aggression, not interspecific mating, drives character displacement in the wing coloration of male rubyspot damselflies (Hetaerina)

Science.gov (United States)

Drury, J. P.; Grether, G. F.

2014-01-01

Traits that mediate intraspecific social interactions may overlap in closely related sympatric species, resulting in costly between-species interactions. Such interactions have principally interested investigators studying the evolution of reproductive isolation via reproductive character displacement (RCD) or reinforcement, yet in addition to reproductive interference, interspecific trait overlap can lead to costly between-species aggression. Previous research on rubyspot damselflies (Hetaerina spp.) demonstrated that sympatric shifts in male wing colour patterns and competitor recognition reduce interspecific aggression, supporting the hypothesis that agonistic character displacement (ACD) drove trait shifts. However, a recent theoretical model shows that RCD overshadows ACD if the same male trait is used for both female mate recognition and male competitor recognition. To determine whether female mate recognition is based on male wing coloration in Hetaerina, we conducted a phenotype manipulation experiment. Compared to control males, male H. americana with wings manipulated to resemble a sympatric congener (H. titia) suffered no reduction in mating success. Thus, female mate recognition is not based on species differences in male wing coloration. Experimental males did, however, experience higher interspecific fighting rates and reduced survival compared to controls. These results greatly strengthen the case for ACD and highlight the mechanistic distinction between ACD and RCD. PMID:25339724

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

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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.

Effect of mating activity and dominance rank on male masturbation among free-ranging male rhesus macaques.

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Dubuc, Constance; Coyne, Sean P; Maestripieri, Dario

2013-11-01

The adaptive function of male masturbation is still poorly understood, despite its high prevalence in humans and other animals. In non-human primates, male masturbation is most frequent among anthropoid monkeys and apes living in multimale-multifemale groups with a promiscuous mating system. In these species, male masturbation may be a non-functional by-product of high sexual arousal or be adaptive by providing advantages in terms of sperm competition or by decreasing the risk of sexually transmitted infections. We investigated the possible functional significance of male masturbation using behavioral data collected on 21 free-ranging male rhesus macaques ( Macaca mulatta ) at the peak of the mating season. We found some evidence that masturbation is linked to low mating opportunities: regardless of rank, males were most likely to be observed masturbating on days in which they were not observed mating, and lower-ranking males mated less and tended to masturbate more frequently than higher-ranking males. These results echo the findings obtained for two other species of macaques, but contrast those obtained in red colobus monkeys ( Procolobus badius ) and Cape ground squirrels ( Xerus inauris ). Interestingly, however, male masturbation events ended with ejaculation in only 15% of the observed masturbation time, suggesting that new hypotheses are needed to explain masturbation in this species. More studies are needed to establish whether male masturbation is adaptive and whether it serves similar or different functions in different sexually promiscuous species.

[Photosynthesis and transpiration characteristics of female and male Trichosanthes kirilowii Maxim individuals].

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Liu, Yun; Zhong, Zhang-cheng; Wang, Xiao-xue; Xie, Jun; Yang, Wen-ying

2011-03-01

A field research was conducted on the photosynthesis and transpiration characteristics of dioecious Trichosanthes kirilowii individuals at four key development stages. At vegetative growth stage, the photosynthesis rate, transpiration rate, stomatal conductance, and water use efficiency of male individuals were higher than those of female individuals, and hence, male individuals entered into reproductive growth stage 22 days earlier than female individuals. After entering into reproductive growth stage, male individuals had higher photosynthesis rate, transpiration rate, and stomatal conductance, but slightly lower water use efficiency than female individuals. As the female individuals started to reproductive growth, their photosynthesis rate and water use efficiency were significantly lower, while the transpiration rate and stomatal conductance were higher than those of the male individuals. The effects of climate factors on the growth and development of T. kirilowii mainly occurred at its vegetative growth and early reproductive growth stages, and weakened at later reproductive growth stages. Higher temperature and lower relative humidity benefited the growth and development of T. kirilowii, and illumination could enhance the photosynthesis rate of T. kirilowii, especially its male individuals. After entering into reproductive growth stage, the photosynthesis rate of male individuals increased significantly with increasing illumination, but that of female individuals only had a slight increase, and the transpiration rate of male individuals as well as the photosynthesis rate of female individuals all increased significantly with increasing temperature.

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

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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.

Male depression in females?

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Möller-Leimkühler, Anne Maria; Yücel, Mete

2010-02-01

Scientific evidence for a male-typed depression ("male depression") is still limited, but mainly supports this concept with respect to single externalizing symptoms or symptom clusters. In particular, studies on non-clinical populations including males and females are lacking. The present study aims at assessing general well-being, the risk and the symptoms of male depression dependent on biological sex and gender-role orientation on instrumental (masculine) and expressive (feminine) personality traits in an unselected community sample of males and females. Students (518 males, 500 females) of the Ludwig-Maximilians-University of Munich, Germany, were asked to participate in a "stress study" and complete the following self-report questionnaires: the WHO-5 Well-being Index [Bech, P., 1998. Quality of Life in the Psychiatric Patient. Mosby-Wolfe, London], the Gotland Scale for Male Depression [Walinder, J., Rutz, W., 2001. Male depression and suicide. International Clinical Psychopharmacology 16 (suppl 2), 21-24] and the German Extended Personal Attribute Questionnaire [Runge, T.E., Frey, D., Gollwitzer, P.M., et al., 1981. Masculine (instrumental) and feminine (expressive) traits. A comparison between students in the United States and West Germany. Journal of Cross-Cultural Psychology 12, 142-162]. General well-being of the students was significantly lower compared to population norms. Contrary to expectations, female students had a greater risk of male depression than male students (28.9% vs. 22.4%; p<0.05). Overall, prototypic depressive symptoms as well as externalizing symptoms were more pronounced in females. In the subgroup of those at risk for male depression, biological sex and kind of symptoms were unrelated. Principal component analyses revealed a similar symptom structure for males and females. Low scores on masculinity/instrumentality significantly predicted higher risk of male depression, independent of biological sex. The study sample is not

Endogenous antispermatogenic agents: prospects for male contraception.

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Ewing, L L; Robaire, B

1978-01-01

A review of endogenous antispermatogenic agents as prospects for male contraception is reported. It is demonstrated that endogenous compounds exert regulatory influences at 4 major levels in the male: 1) between germ cells; 2) between Sertoli and germ cells; 3) between Leydig cells and seminiferous tubules; and 4) between the central nervous system and the testis. Efforts to interrupt spermatogenesis have failed to find application as male contraceptives for various reasons: 1) some investigators ignored the vulnerable control points by utilizing nonspecific agents; 2) others attacked a vulnerable control point but used synthetic drugs that had deleterious side effects; and 3) still others attacked a vulnerable control point with a relatively innocuous drug but used an impractical mode of drug administration. The potential for devising innovative techniques for administering relatively innocuous drugs at dosages sufficient to produce sterility without causing deleterious side effects is demonstrated. The most promising solution for the development of an antispermatogenic male contraceptive is the interference with the adenohypophyseal-gonadal axis via the subcutaneous sustained release of steroid formulations containing either androgen-danazol, androgen-progestin, or androgen-estrogen formulations. Another promising agent would be luteinizing releasing hormone agonist-androgen formulation.

Higher cardiorespiratory and muscular fitness in males could not be attributed to physical activity, sports practice or sedentary behavior in young people

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Diogo Henrique Constantino Coledam

2018-03-01

Full Text Available The purpose of the present study was to analyze if the association between sex with cardiorespiratory and muscular fitness is independent of physical activity, sports practice and sedentary behavior in young people. A cross-sectional study involving 729 participants aged 10 to 17 years. Physical activity, sports practice and sedentary behavior were assessed through a questionnaire. Cardiorespiratory fitness was measured using 20m shuttle run test and were analyzed: VO2max, number of laps and health-related criteria. Muscular fitness was assessed with 90o push-up test and number of repetition and health-related criteria was analyzed. Multiple linear regression was used to estimate β coeficients and Poisson regression estimated prevalence ratios (PR. Male sex was associated to higher cardiorespiratory fitness (VO2max β = 9.04 to 9.77, Laps PR=1.67 to 1.80, health-related criteria PR=2.03 to 2.09 and the same occurred with muscular fitness (repetitions PR=2.81 to 3.01, health-related criteria PR=1.91 to 2.09. Similarly, the stratification of the sample according to physical activity, sports practice and sedentary behavior did not change the associations between sex with cardiorespiratory (VO2max β=8.07 to 10.00, Laps PR=1.49 to 1.85, health-related criteria PR=1.64 to 2.27 and muscular fitness (repetitions PR=2.24 to 3.22, health-related criteria PR=1.76 to 2.06. These data suggest that higher cardiorespiratory and muscular fitness in males could not be attributed to physical activity, sports practice or sedentary behavior in young people.

Male brush-turkeys attempt sexual coercion in unusual circumstances.

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

2014-07-01

Sexual coercion by males is generally understood to have three forms: forced copulation, harassment and intimidation. We studied Australian brush-turkeys, Alectura lathami, to determine whether some male behaviours towards females at incubation mounds could be classified as aggressive, whether males were attempting sexual coercion and, if so, whether the coercion was successful. We found that some male behaviours towards females were significantly more likely to be followed by the cessation of female mound activity, and hence could be classified as aggressive, while others were significantly more likely to be followed by the commencement of female mound activity, and hence could be classified as enticing. Copulation was preceded by higher rates of male enticement and by higher rates of certain types of male aggression. It therefore seemed that males were attempting sexual coercion. There was little evidence, however, that this combination of coercion and enticement was successful in obtaining copulations. While forced copulation did occur, it was infrequent, and no evidence could be found for intimidation. We conclude that harassment is the primary form of sexual coercion by male brush-turkeys. Although sexual coercion is understood to be a sub-optimal tactic, brush-turkey sexual coercion was employed as a primary tactic by dominant males who owned incubation mounds. One possible explanation for this apparent paradox is that aggression is the default solution for social conflicts in this species, and hence can be interpreted as a behavioural syndrome. Copyright © 2014 Elsevier B.V. All rights reserved.

Stress, social behaviour, and secondary sexual traits in a male primate.

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Setchell, Joanna M; Smith, Tessa; Wickings, E Jean; Knapp, Leslie A

2010-11-01

We examined variation in glucocorticoid levels in the mandrill, a brightly coloured primate species, to identify major social influences on stress hormones, and investigate relationships among glucocorticoid levels, testosterone and secondary sexual ornamentation. We collected a total of 317 fecal samples for 16 adult male mandrills over 13 months, including mating and non-mating periods and periods of both dominance rank stability and instability, and compared fecal glucocorticoid levels with dominance rank, rank stability, presence of receptive females, gastro-intestinal parasite infection, fecal testosterone and facial red coloration. Glucocorticoid levels did not vary systematically with dominance rank, but increased when the dominance hierarchy was unstable, and increased in the presence of receptive females. The relationship between dominance rank and glucocorticoid levels changed direction according to the stability of the dominance hierarchy: glucocorticoid levels were higher in subordinate males under stable conditions, but under conditions of instability higher ranking males had higher glucocorticoid levels. The influence of dominance rank also interacted with the presence of receptive females: glucocorticoids were higher in dominant males than in subordinates, but only during mating periods, suggesting that dominant males are more stressed than subordinates during such periods. These findings support previous studies showing that the relationship between glucocorticoids and dominance rank in male baboons is dependent on the social environment. We also found that males with higher glucocorticoids suffered a higher diversity of gastrointestinal parasite infection, in line with evidence that glucocorticoids suppress the immune system in other species. However, we found no support for the stress-mediated immunocompetence handicap hypothesis for the evolution of condition-dependent ornaments: glucocorticoid and testosterone levels were positively related

Sexy faces in a male paper wasp.

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André Rodrigues de Souza

Full Text Available Sexually selected signals are common in many animals, though little reported in social insects. We investigated the occurrence of male visual signals mediating the dominance relationships among males and female choice of sexual partner in the paper wasp Polistes simillimus. Males have three conspicuous, variable and sexually dimorphic traits: black pigmentation on the head, a pair of yellow abdominal spots and body size differences. By conducting behavioral assays, we found that none of the three visual traits are associated with male-male dominance relationship. However, males with higher proportion of black facial pigmentation and bigger yellow abdominal spots are more likely chosen as sexual partners. Also, after experimentally manipulating the proportion of black pigment on males' face, we found that females may evaluate male facial coloration during the choice of a sexual partner. Thus, the black pigmentation on P. simillimus male's head appears to play a role as a sexually selected visual signal. We suggest that sexual selection is a common force in Polistes and we highlight the importance of this group as a model for the study of visual communication in insects.

Male access to emergency contraception in pharmacies: a mystery shopper survey.

Science.gov (United States)

Bell, David L; Camacho, Elvis J; Velasquez, Andrew B

2014-10-01

Pharmacy access to emergency contraception (EC) could involve men in pregnancy prevention. The objectives were to assess the availability and cost of EC. Male mystery shoppers visited 158 pharmacies in three neighborhoods in New York City. They asked for EC and its cost and noted weekend hours. Twenty-two (73.3%) of 30 pharmacies created barriers to get EC. The cost of EC was higher in the higher-socioeconomic status (SES) neighborhood (p<.001), and the higher-SES neighborhood pharmacies had a greater number of weekend hours (p<.001). Overall, males had a 20% probability of not being able to access EC. The national dialogue should include males. Copyright © 2014 Elsevier Inc. All rights reserved.

Divergent expression of 11beta-hydroxysteroid dehydrogenase and 11beta-hydroxylase genes between male morphs in the central nervous system, sonic muscle and testis of a vocal fish.

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Arterbery, Adam S; Deitcher, David L; Bass, Andrew H

2010-05-15

The vocalizing midshipman fish, Porichthys notatus, has two male morphs that exhibit alternative mating tactics. Only territorial males acoustically court females with long duration (minutes to >1h) calls, whereas sneaker males attempt to steal fertilizations. During the breeding season, morph-specific tactics are paralleled by a divergence in relative testis and vocal muscle size, plasma levels of the androgen 11-ketotestosterone (11KT) and the glucocorticoid cortisol, and mRNA expression levels in the central nervous system (CNS) of the steroid-synthesizing enzyme aromatase (estrogen synthase). Here, we tested the hypothesis that the midshipman's two male morphs would further differ in the CNS, as well as in the testis and vocal muscle, in mRNA abundance for the enzymes 11beta-hydroxylase (11betaH) and 11beta-hydroxysteroid dehydrogenase (11betaHSD) that directly regulate both 11KT and cortisol synthesis. Quantitative real-time PCR demonstrated male morph-specific profiles for both enzymes. Territorial males had higher 11betaH and 11betaHSD mRNA levels in testis and vocal muscle. By contrast, sneaker males had the higher CNS expression, especially for 11betaHSD, in the region containing an expansive vocal pacemaker circuit that directly determines the temporal attributes of natural calls. We propose for territorial males that higher enzyme expression in testis underlies its greater plasma 11KT levels, which in vocal muscle provides both gluconeogenic and androgenic support for its long duration calling. We further propose for sneaker males that higher enzyme expression in the vocal CNS contributes to known cortisol-specific effects on its vocal physiology. Copyright 2010 Elsevier Inc. All rights reserved.

Neuroticism Associates with Cerebral in Vivo Serotonin Transporter Binding Differently in Males and Females

DEFF Research Database (Denmark)

Tuominen, Lauri; Miettunen, Jouko; Cannon, Dara M

2017-01-01

scores from 91 healthy males and 56 healthy females. We specifically tested if the association between neuroticism and serotonin transporter is different in females and males. Results: We found that neuroticism and thalamic serotonin transporter binding potentials were associated in both males......). Conclusions: The finding is in agreement with recent studies showing that the serotonergic system is involved in affective disorders differently in males and females and suggests that contribution of thalamic serotonin transporter to the risk of affective disorders depends on sex....... and females, but with opposite directionality. Higher neuroticism associated with higher serotonin transporter binding potential in males (standardized beta 0.292, P=.008), whereas in females, higher neuroticism associated with lower serotonin transporter binding potential (standardized beta -0.288, P=.014...

Hormonal contraceptive use and mate retention behavior in women and their male partners.

Science.gov (United States)

Welling, Lisa L M; Puts, David A; Roberts, S Craig; Little, Anthony C; Burriss, Robert P

2012-01-01

Female hormonal contraceptive use has been associated with a variety of physical and psychological side effects. Women who use hormonal contraceptives report more intense affective responses to partner infidelity and greater overall sexual jealousy than women not using hormonal contraceptives. Recently, researchers have found that using hormonal contraceptives with higher levels of synthetic estradiol, but not progestin, is associated with significantly higher levels of self-reported jealousy in women. Here, we extend these findings by examining the relationship between mate retention behavior in heterosexual women and their male partners and women's use of hormonal contraceptives. We find that women using hormonal contraceptives report more frequent use of mate retention tactics, specifically behaviors directed toward their partners (i.e., intersexual manipulations). Men partnered with women using hormonal contraceptives also report more frequent mate retention behavior, although this relationship may be confounded by relationship satisfaction. Additionally, among women using hormonal contraceptives, the dose of synthetic estradiol, but not of synthetic progesterone, positively predicts mate retention behavior frequency. These findings demonstrate how hormonal contraceptive use may influence behavior that directly affects the quality of romantic relationships as perceived by both female and male partners. Published by Elsevier Inc.

Bone geometry in young male and female football players: a peripheral quantitative computed tomography (pQCT) study.

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Lozano-Berges, Gabriel; Matute-Llorente, Ángel; Gómez-Bruton, Alejandro; González-Agüero, Alex; Vicente-Rodríguez, Germán; Casajús, José A

2018-05-08

The present study shows that football practice during growth may improve bone geometry in male and female football players. However, only females had better bone strength in comparison with controls. The aim of this study was to compare bone geometry in adolescent football players and controls. A total of 107 football players (71 males/36 females; mean age 12.7 ± 0.6/12.7 ± 0.6 years) and 42 controls (20 males/22 females; mean age 13.1 ± 1.4/12.7 ± 1.3 years) participated in this study. Total and trabecular volumetric bone mineral content (Tt.BMC/Tb.BMC), cross-sectional area (Tt.Ar/Tb.Ar), and bone strength index (BSI) were measured at 4% site of the non-dominant tibia by peripheral quantitative computed tomography (pQCT). Moreover, Tt.BMC, cortical BMC (Ct.BMC), Tt.Ar, cortical Ar (Ct.Ar), cortical thickness (Ct.Th), periosteal circumference (PC), endosteal circumference (EC), fracture load in X-axis, and polar strength strain index (SSIp) were measured at 38% site of the tibia. Multivariate analyses of covariance were used to compare bone pQCT variables between football players and controls using the tibia length and maturity offset as covariates. Female football players demonstrated 13.8-16.4% higher BSI, Ct.Th, fracture load in X-axis, and SSIp than controls (p  .0036). In relation to bone mineral content and area, male football players showed 8.8% higher Tt.Ar and Tb.Ar at the 4% site of the tibia when compared to controls; whereas 13.8-15.8% higher Tt.BMC, Ct.BMC, and Ct.Ar at the 38% site of the tibia were found in female football players than controls (p female adolescent football players presented better bone geometry and strength values than controls. In contrast, only bone geometry was higher in male football players than controls.

Differential metabolism of acrylonitrile to cyanide is responsible for the greater sensitivity of male vs female mice: role of CYP2E1 and epoxide hydrolases

International Nuclear Information System (INIS)

Chanas, Brian; Wang, Hongbing; Ghanayem, Burhan I.

2003-01-01

Acrylonitrile (AN) is a potent toxicant and a known rodent carcinogen. AN epoxidation to cyanoethylene oxide (CEO) via CYP2E1 and its subsequent metabolism via epoxide hydrolases (EH) to yield cyanide is thought to be responsible for the acute toxicity and mortality of AN. Recent reports showed that male mice are more sensitive than females to the acute toxicity/mortality of AN. The present work was undertaken to assess the metabolic and enzymatic basis for the greater sensitivity of male vs female mice to AN toxicity. Male and female wild-type and CYP2E1-null mice received AN at 0, 2.5, 10, 20, or 40 mg/kg by gavage. Cyanide concentrations were measured at 1 or 3 h after dosing. Current data demonstrated that cyanide levels in blood and tissues of AN-treated wild-type mice of both sexes were significantly greater than in vehicle-treated controls and increased in a dose-dependent manner. In contrast, cyanide levels in AN-treated CYP2E1-null mice were not statistically different from those measured in vehicle-treated controls. Furthermore, higher levels of cyanide were detected in male wild-type mice vs females in association with greater sensitivity of males to the acute toxicity/mortality of this chemical. Using Western blot analysis, negligible difference in CYP2E1 expression with higher levels of soluble and microsomal EH (sEH and mEH) was detected in the liver of male vs female mice. In kidneys, male mice exhibited higher expression of both renal CYP2E1 and sEH than did female mice. In conclusion, higher blood and tissue cyanide levels are responsible for the greater sensitivity of male vs female mice to AN. Further, higher expression of CYP2E1 and EH in male mice may contribute to greater formation of CEO and its subsequent metabolism to yield cyanide, respectively

Comparison of Neurological Function in Males and Females from Two Substrains of C57BL/6 Mice

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Amy Ashworth

2014-12-01

Full Text Available The C57BL/6 (B6 mouse is the background strain most frequently used for genetically-modified mice. Previous studies have found significant behavioral and genetic differences between the B6J (The Jackson Laboratory and B6N substrains (National Institutes of Health; however, most studies employed only male mice. We performed a comprehensive battery of motor function and learning and memory tests on male and female mice from both substrains. The B6N male mice had greater improvement in the rotarod test. In contrast, B6J female mice had longer latencies to falling from the rotarod. In the Morris water maze (MWM, B6J males had significantly shorter latencies to finding the hidden platform. However, B6N females had significantly shorter path lengths in the reversal and shifted-reduced phases. In open field locomotor activity, B6J males had higher activity levels, whereas B6N females took longer to habituate. In the fear conditioning test, B6N males had a significantly longer time freezing in the new context compared with B6J males, but no significant differences were found in contextual or cued tests. In summary, our findings demonstrate the importance of testing both males and females in neurobehavioral studies. Both factors (sex and substrain must be taken into account when designing developmental neurotoxicology studies.

Muscle dysmorphia in Hungarian non-competitive male bodybuilders.

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Babusa, B; Túry, F

2012-03-01

Muscle dysmorphia (MD) has been described as a male body image disorder, characterized by a pathological preoccupation with muscle size. The aim of the study was to examine the MD features, eating disorder characteristics and body attitudes in non-competitive male bodybuilders in a Hungarian sample. Sixty male bodybuilders and 60 undergraduate university students completed the self-report questionnaires of the Muscle Appearance Satisfaction Scale, the Body Attitude Test and the Eating Disorders Inventory. MD was associated with current bodybuilding activity, higher ideal body weight and eating disorder characteristics. Moreover, current selfreported steroid users displayed higher tendency for MD symptoms than self-reported steroid non-users. Results emphasize the relationship between MD symptoms, eating disorder characteristics and steroid use. MD and body image related concerns among men could be a wide-spread phenomena also in the Central-Eastern European region.

Effect of gamma irradiation on fertility of potato tuber moth males and study of inherited sterility phenomena in partially sterile males

International Nuclear Information System (INIS)

Saour, G.; Makee, H.

1996-01-01

Newly emerged adult males (0-18 h) potato tuber moth (PTM) phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) were irradiated with various doses of gamma irradiation ranging from 5 to 45 krad. Sterility in order of 91% was induced when males were irradiated with a dose of 45 Krad. Longevity of male PTM was not affected by the application of irradiation, while mating ability and frequency of mating of the males irradiated with 25, 35 and 45 Krad were decreased. The mean number of eggs laid by females mated with males irradiated at 35 and 45 Krad was lower than the control. When males PTM were irradiated with high doses their competitiveness values were reduced, while the competitiveness was increased when the sex ratio of irradiated males to normal males was increased, specially with ration 1 : 10 : 1 (Normal male: Irradiated males: Normal female). Application of 15 Krad dose permitted, the ability to obtain a desired level of male sterility with acceptable reduction in its competitiveness. The inherited sterility phenomena in partially sterile males irradiated with 10-15 and 20 Krad was studied. Sterility in F1 progeny was higher than that in their irradiated male parents. The sex ratio of F1 progeny was distorted in favour of the males. (author). 24 refs., 5 figs

Effect of gamma irradiation on fertility of potato tuber moth males and study of inherited sterility phenomena in partially sterile males

Energy Technology Data Exchange (ETDEWEB)

Saour, G; Makee, H [Atomic Energy Commission, Damascus (Syrian Arab Republic). Dept. of Radiation Agriculture

1996-01-01

Newly emerged adult males (0-18 h) potato tuber moth (PTM) phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) were irradiated with various doses of gamma irradiation ranging from 5 to 45 krad. Sterility in order of 91% was induced when males were irradiated with a dose of 45 Krad. Longevity of male PTM was not affected by the application of irradiation, while mating ability and frequency of mating of the males irradiated with 25, 35 and 45 Krad were decreased. The mean number of eggs laid by females mated with males irradiated at 35 and 45 Krad was lower than the control. When males PTM were irradiated with high doses their competitiveness values were reduced, while the competitiveness was increased when the sex ratio of irradiated males to normal males was increased, specially with ration 1 : 10 : 1 (Normal male: Irradiated males: Normal female). Application of 15 Krad dose permitted, the ability to obtain a desired level of male sterility with acceptable reduction in its competitiveness. The inherited sterility phenomena in partially sterile males irradiated with 10-15 and 20 Krad was studied. Sterility in F1 progeny was higher than that in their irradiated male parents. The sex ratio of F1 progeny was distorted in favour of the males. (author). 24 refs., 5 figs.

Behavioral tactics of male sockeye salmon (Oncorhynchus nerka) under varying operating sex ratios

Science.gov (United States)

Quinn, Thomas P.; Adkison, Milo D.; Ward, Michael B.

1996-01-01

Previous studies have demonstrated several reproductive-behavior patterns in male salmon, including competitive and sneaking tactics, the formation of hierarchies, and non-hierarchical aggregations around ripe females. Through behavioral observations at varying spatial and temporal scales, we examined the hypothesis that operational sex ratio (OSR) determines male sockeye salmon (Oncorhynchus nerka) distribution and breeding tactics. Patterns of male distribution and behavior varied over both coarse and fine scales, associated with apparent shifts in reproductive opportunities, the physical characteristics of the breeding sites, and the deterioration of the fish as they approached death. Females spawned completely within a few days of arriving on the spawning grounds, whereas males courted the available ripe females from the date of their arrival on the spawning ground until their death. This difference in reproductive lifespans tended to elevate late-season OSRs but was partially counterbalanced by male departures and the arrival of other ripe females. The proportion of males able to dominate access to ripe females decreased and the number of large courting groups increased over the course of the season, apparently related to both increasing OSR and the deteriorating physical condition of males. However, great variation in OSR was observed within the spawning sites on a given day. OSRs were generally higher in shallow than in deep water, perhaps because larger females or more desirable breeding sites were concentrated in shallow water. The aggregations of males courting females were not stable (i.e. many arrivals and departures took place) and male aggression varied with group size. Aggression was most frequent at low OSRs and in groups of intermediate size (2–4 males per female), and much less frequent in larger groups, consistent with the needs of maximizing reproductive opportunities while minimizing unproductive energy expenditure. These results indicate

Cortisol secretion after adrenocorticotrophin (ACTH and Dexamethasone tests in healthy female and male dogs

Directory of Open Access Journals (Sweden)

Castillo Victor

2009-08-01

Full Text Available Abstract Background For the conclusive diagnosis of Cushing's Syndrome, a stimulating ACTH test or a low suppressive Dexamethasone test is used. Reports in other species than the dog indicate that plasma cortisol concentration after ACTH administration is affected by gender. We investigated the effect of gender on the cortisol response to ACTH and Dexamethasone tests in dogs. Methods Seven healthy adult Cocker Spaniels (4 females and 3 males were assigned to a two by two factorial design: 4 dogs (2 females and 2 males received IV Dexamethasone 0.01 mg/kg, while the other 3 dogs received an IV saline solution (control group. Two weeks later the treatments were reversed. After one month, ACTH was given IV (250 μg/animal to 4 dogs (2 female and 2 males while the rest was treated with saline solution (control group. Cortisol concentrations were determined by a direct solid-phase radioimmunoassay and cholesterol and triglycerides by commercial kits. Results and Discussion No effect of treatment was observed in metabolite concentrations, but females presented higher cholesterol concentrations. ACTH-treated dogs showed an increase in cortisol levels in the first hour after sampling until 3 hours post injection. Cortisol concentrations in Dexamethasone-treated dogs decreased one hour post injection and remained low for 3 hours, thereafter cortisol concentrations increased. The increase in cortisol levels from one to two hours post ACTH injection was significantly higher in females than males. In Dexamethasone-treated males cortisol levels decreased one hour post injection up to 3 hours; in females the decrease was more pronounced and prolonged, up to 5 hours post injection. Conclusion We have demonstrated that cortisol response to ACTH and Dexamethasone treatment in dogs differs according to sex.

Familial patterning and prevalence of male androphilia among Istmo Zapotec men and muxes.

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Francisco R Gómez

Full Text Available Male androphilia (i.e., male sexual attraction to other adult males is known to cluster within families. Some studies demonstrate that male androphilia clusters in both the paternal and maternal familial lines, whereas other studies demonstrated that it clusters only in the latter. Most of these studies were conducted in Euro-American populations where fertility is low and the sexual orientation of male relatives can sometimes be difficult to ascertain. These two factors can potentially confound the results of such studies. To address these limitations, we examined the familial patterning of male androphilia among the Istmo Zapotec of Oaxaca, Mexico--a high fertility, non-Euro-American population where androphilic males are known locally as muxes, a third gender category. The Istmo Zapotec recognize two types of muxes--muxe gunaa and muxe nguiiu--who typify the transgender and cisgender forms of male androphilia, respectively. We compared the familial patterning of male androphilia between muxe gunaa and muxe nguiiu, as well as between gynephilic men and muxes (both cisgender and transgender forms combined. Istmo Zapotec muxe gunaa and muxe nguiiu exhibit similar familial patterning of male androphilia. Overall, muxes were characterized by significantly more muxe relatives than gynephilic men. This familial patterning was equivalent in both the paternal and maternal lines of muxes. The population prevalence rate of male androphilia was estimated to fall between 3.37-6.02% in the Istmo Zapotec. This is the first study that has compared cisgender and transgender androphilic males from the same high fertility population and demonstrated that the two do not differ with respect to the familial patterning of male androphilia.

Familial patterning and prevalence of male androphilia among Istmo Zapotec men and muxes.

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Gómez, Francisco R; Semenyna, Scott W; Court, Lucas; Vasey, Paul L

2018-01-01

Male androphilia (i.e., male sexual attraction to other adult males) is known to cluster within families. Some studies demonstrate that male androphilia clusters in both the paternal and maternal familial lines, whereas other studies demonstrated that it clusters only in the latter. Most of these studies were conducted in Euro-American populations where fertility is low and the sexual orientation of male relatives can sometimes be difficult to ascertain. These two factors can potentially confound the results of such studies. To address these limitations, we examined the familial patterning of male androphilia among the Istmo Zapotec of Oaxaca, Mexico--a high fertility, non-Euro-American population where androphilic males are known locally as muxes, a third gender category. The Istmo Zapotec recognize two types of muxes--muxe gunaa and muxe nguiiu--who typify the transgender and cisgender forms of male androphilia, respectively. We compared the familial patterning of male androphilia between muxe gunaa and muxe nguiiu, as well as between gynephilic men and muxes (both cisgender and transgender forms combined). Istmo Zapotec muxe gunaa and muxe nguiiu exhibit similar familial patterning of male androphilia. Overall, muxes were characterized by significantly more muxe relatives than gynephilic men. This familial patterning was equivalent in both the paternal and maternal lines of muxes. The population prevalence rate of male androphilia was estimated to fall between 3.37-6.02% in the Istmo Zapotec. This is the first study that has compared cisgender and transgender androphilic males from the same high fertility population and demonstrated that the two do not differ with respect to the familial patterning of male androphilia.

The evolution of postpairing male mate choice.

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Lyu, Nan; Servedio, Maria R; Lloyd, Huw; Sun, Yue-Hua

2017-06-01

An increasing number of empirical studies in animals have demonstrated male mate choice. However, little is known about the evolution of postpairing male choice, specifically which occurs by differential allocation of male parental care in response to female signals. We use a population genetic model to examine whether such postpairing male mate choice can evolve when males face a trade-off between parental care and extra-pair copulations (EPCs). Specifically, we assume that males allocate more effort to providing parental care when mated to preferred (signaling) females, but they are then unable to allocate additional effort to seek EPCs. We find that both male preference and female signaling can evolve in this situation, under certain conditions. First, this evolution requires a relatively large difference in parental investment between males mated to preferred versus nonpreferred females. Second, whether male choice and female signaling alleles become fixed in a population versus cycle in their frequencies depends on the additional fecundity benefits from EPCs that are gained by choosy males. Third, less costly female signals enable both signaling and choice alleles to evolve under more relaxed conditions. Our results also provide a new insight into the evolution of sexual conflict over parental care. © 2017 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

Nutritional effects on male calling behaviour in the variable field cricket.

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Wagner; Hoback

1999-01-01

In the variable field cricket, Gryllus lineaticeps, females prefer higher chirp rates and longer chirp durations in male calling song. Higher chirp rates are energetically more expensive to produce, but the energetic cost of calling does not vary with chirp duration. We tested the hypothesis that nutrition affects male chirp rate and chirp duration. Full-sibling brothers of similar age were placed on high- and low-nutrition feeding regimes. There was no effect of feeding regime on male weight; neither group showed a significant change in weight, and the two groups did not differ from each other in weight change. However, males on the high-nutrition feeding regime both called more frequently and called at higher chirp rates when they did call. The two groups did not differ in chirp duration, the duration of pulses within chirps or chirp dominant frequency. These results suggest that females select mates based on one nutrition-dependent call character (chirp rate) and one nutrition-independent call character (chirp duration). In addition, because males in the two groups did not show significant differences in weight change, and because males on the high-nutrition feeding regime engaged in energetically more expensive calling, these results suggest that males invest any excess energy above their basic maintenance requirements in the production of call types that increase their attractiveness to females. The absence of a relationship between body condition and calling song structure for males in the field may be a consequence of this pattern of energy allocation. Copyright 1999 The Association for the Study of Animal Behaviour.

[The reproductive correlates of social hierarchy in laboratory male mice].

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Osadchuk, L B; Salomacheva, I N; Bragin, A V; Osadchuk, A V

2007-01-01

In laboratory male mice the effects of social hierarchy on hormonal and spermatogenic testicular function, accessory organs and testicular weights, sexual behaviour have been investigated using an experimental model of social hierarchy, which is characterised by a minimal size (two male mice) and 5 days period of social interactions. The social rank of the partners was detected by asymmetry in aggressive behaviour. Using the experimental condition, when the both partners have no preferences for exclusive use of area we demonstrated that there were no rank differences in the number of mounts and testicular testosterone content. Nevertheless a rank asymmetry in the male sniffing behaviour towards a receptive female, weights of the testes, seminal vesicles, epididymes and the number of epididymal sperm was kept up in a stable social group. Social dominance was found to affect negatively on testicular testosterone increase in response to introduction of a receptive female and sexual attractiveness of male to a receptive female in both dominant and subordinate males. The results obtained demonstrate the impact of social hierarchy on reproduction in laboratory male mice, particular in respect of spermatogenesis and the testicular testosterone in response to a receptive female.

Consanguinity and family clustering of male factor infertility in Lebanon.

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Inhorn, Marcia C; Kobeissi, Loulou; Nassar, Zaher; Lakkis, Da'ad; Fakih, Michael H

2009-04-01

To investigate the influence of consanguineous marriage on male factor infertility in Lebanon, where rates of consanguineous marriage remain high (29.6% among Muslims, 16.5% among Christians). Clinic-based, case-control study, using reproductive history, risk factor interview, and laboratory-based semen analysis. Two IVF clinics in Beirut, Lebanon, during an 8-month period (January-August 2003). One hundred twenty infertile male patients and 100 fertile male controls, distinguished by semen analysis and reproductive history. None. Standard clinical semen analysis. The rates of consanguineous marriage were relatively high among the study sample. Patients (46%) were more likely than controls (37%) to report first-degree (parental) and second-degree (grandparental) consanguinity. The study demonstrated a clear pattern of family clustering of male factor infertility, with patients significantly more likely than controls to report infertility among close male relatives (odds ratio = 2.58). Men with azoospermia and severe oligospermia showed high rates of both consanguinity (50%) and family clustering (41%). Consanguineous marriage is a socially supported institution throughout the Muslim world, yet its relationship to infertility is poorly understood. This study demonstrated a significant association between consanguinity and family clustering of male factor infertility cases, suggesting a strong genetic component.

Sexual Selection on male cuticular hydrocarbons via male-male competition and female choice.

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Lane, S M; Dickinson, A W; Tregenza, T; House, C M

2016-07-01

Traditional views of sexual selection assumed that male-male competition and female mate choice work in harmony, selecting upon the same traits in the same direction. However, we now know that this is not always the case and that these two mechanisms often impose conflicting selection on male sexual traits. Cuticular hydrocarbons (CHCs) have been shown to be linked to both social dominance and male attractiveness in several insect species. However, although several studies have estimated the strength and form of sexual selection imposed on male CHCs by female mate choice, none have established whether these chemical traits are also subject to sexual selection via male-male competition. Using a multivariate selection analysis, we estimate and compare sexual selection exerted by male-male competition and female mate choice on male CHC composition in the broad-horned flour beetle Gnatocerus cornutus. We show that male-male competition exerts strong linear selection on both overall CHC abundance and body size in males, while female mate choice exerts a mixture of linear and nonlinear selection, targeting not just the overall amount of CHCs expressed but the relative abundance of specific hydrocarbons as well. We discuss the potential implications of this antagonistic selection with regard to male reproductive success. © 2016 The Authors. Journal of Evolutionary Biology published by John Wiley & Sons Ltd on behalf of European Society for Evolutionary Biology.

Male and female sterility in Zambia

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Athena Pantazis

2014-02-01

Full Text Available Background: Population measures of sterility are traditionally constructed for women, despite fertility and sterility being conditions of the couple. Estimates of male sterility provide insight into population-level sterility, and complement estimates based solely on women. Objective: This study seeks to estimate male sterility for the Gwembe Tonga of Zambia using male birth histories collected by the Gwembe Tonga Research Project from 1957 to 1995, while providing context by estimating female sterility for the Gwembe Tonga, as well as female sterility in all of Zambia, from Zambian DHS data (1992, 1997, 2001-02, and 2007. Methods: Sterility is measured using the Larson-Menken subsequently infertile indicator. Estimates are produced using discrete time event history analysis. Results: The odds of sterility were higher for women than men, though women's odds of sterility were only 1.5 times that of men's in the middle reproductive years. The odds of sterility increased steadily with age for both men and women, and across all datasets. However, women's sterility increased much more sharply with age than men's did, and women's odds of sterility were higher than men's at all reproductive ages.

Smoking, internalized heterosexism, and HIV disease management among male couples.

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Gamarel, K E; Neilands, T B; Dilworth, S E; Taylor, J M; Johnson, M O

2015-01-01

High rates of cigarette smoking have been observed among HIV-positive individuals. Smoking has been linked to HIV-related medical complications and non-AIDS defining cancers and negatively impacts on immune function and virologic control. Although internalized heterosexism has been related to smoking behaviors, little is known about associations between partners' reports of smoking, internalized heterosexism, and HIV medication management in male couples with HIV. A sample of 266 male couples completed baseline assessments for a cohort study examining relationship factors and HIV treatment. A computer-based survey assessed self-reported smoking behaviors, alcohol use, internalized heterosexism, and antiretroviral therapy (ART) adherence. HIV-positive men also provided blood samples to assess viral load. Approximately 30% of the sample reported that they are currently smoking cigarettes. After adjusting for demographic characteristics, men in a primary relationship with a partner who reported currently smoking had more than five-fold greater odds of reporting smoking. Higher levels of internalized heterosexism and financial hardship were each independently associated with greater odds of reporting smoking. Among HIV-positive men on ART (n = 371), having a partner who reported smoking was associated with almost three-fold greater odds of having a detectable viral load. Our findings add new support to the evidence of romantic partners influencing each other's health behaviors, and demonstrate an association between smoking and disease management within male couples. Future research should explore the interpersonal and social contexts of smoking in order to develop interventions that meet the unique needs of male couples.

A Nightmare for Males? A Maternally Transmitted Male-Killing Bacterium and Strong Female Bias in a Green Lacewing Population.

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Masayuki Hayashi

Full Text Available For maternally transmitted microbes, a female-biased host sex ratio is of reproductive advantage. Here we found a strong female bias in a field population of the green lacewing, Mallada desjardinsi (Insecta; Neuroptera. This bias was attributed to the predominance of individuals harboring a maternally inherited male-killing bacterium that was phylogenetically closely related to the plant-pathogenic Spiroplasma phoeniceum and Spiroplasma kunkelii. Among 35 laboratory-reared broods produced by wild-caught females, 21 broods (60%-all infected with Spiroplasma-consisted of only females (940 individuals. Among 14 broods consisting of both males and females (516 and 635 individuals, respectively, 4 broods were doubly infected with Spiroplasma and Rickettsia, 6 broods were singly infected with Rickettsia, and 3 broods were uninfected (remaining one brood was unknown. Mortality during embryonic and larval development was prominent in all-female broods but not in normal sex ratio broods. Following antibiotic treatment on all-female broods, mortality was significantly reduced and the sex ratio was restored to 1:1. Strong expression and high prevalence of this male-killer is remarkable considering its low density (~10-5-10-4 cells per host mitochondrial gene copy based on quantitative PCR. In addition, a bacterium closely related to Rickettsia bellii was present in 25 of 34 broods (73.5%, irrespective of the sex ratio, with the infection density comparable to other cases of endosymbiosis (~10-2-10-1 cells per mitochondrial gene copy. Higher density of Rickettsia than Spiroplasma was also demonstrated by electron microscopy which visualized both Spiroplasma-like cells and Rickettsia-like cells inside and outside the ovarian cells.

Does a trade-off between current reproductive success and survival affect the honesty of male signalling in species with male parental care?

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Kelly, N B; Alonzo, S H

2010-11-01

Recent theory predicted that male advertisement will reliably signal investment in paternal care in species where offspring survival requires paternal care and males allocate resources between advertisement and care. However, the predicted relationship between care and advertisement depended on the marginal gains from investment in current reproductive traits. Life history theory suggests that these fitness gains are also subject to a trade-off between current and future reproduction. Here, we investigate whether male signalling remains a reliable indicator of parental care when males allocate resources between current advertisement, paternal care and survival to future reproduction. We find that advertisement is predicted to remain a reliable signal of male care but that advertisement may cease to reliably indicate male quality because low-quality males are predicted to invest in current reproduction, whereas higher-quality males are able to invest in both current reproduction and survival to future reproduction. © 2010 The Authors. Journal Compilation © 2010 European Society For Evolutionary Biology.

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.

Male-driven reproductive and agonistic character displacement in darters and its implications for speciation in allopatry

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Fuller, Rebecca C

2018-01-01

Abstract Selection against hybridization can cause mating traits to diverge between species in sympatry via reproductive character displacement (RCD). Additionally, selection against interspecific fighting can cause aggressive traits to diverge between sympatric species via agonistic character displacement (ACD). By directly affecting conspecific recognition traits, RCD and ACD between species can also incidentally cause divergence in mating and fighting traits among populations within a species [termed cascade RCD (CRCD) and cascade ACD]. Here, we demonstrate patterns consistent with male-driven RCD and ACD in 2 groups of darters (orangethroat darter clade Ceasia and rainbow darter Etheostoma caeruleum). In both groups, males that occur in sympatry (between Ceasia and E. caeruleum) have higher levels of preference for mating and fighting with conspecifics over heterospecifics than do males from allopatry. This is consistent with RCD and ACD. We also found patterns consistent with CRCD and cascade ACD among species of Ceasia. Ceasia males that are sympatric to E. caeruleum (but allopatric to one another) also have heightened preferences for mating and fighting with conspecific versus heterospecific Ceasia. In contrast, Ceasia males that are allopatric to E. caeruleum readily mate and fight with heterospecific Ceasia. We suggest that RCD and ACD between Ceasia and E. caeruleum has incidentally led to divergence in mating and fighting traits among Ceasia species. This study is unique in that male preferences evolve via both RCD (male preference for conspecific females) and ACD (male preference to fight conspecific males) which leads to subsequent divergence among allopatric lineages. PMID:29492043

Key health promotion factors among male members of staff at a higher educational institution: A cross-sectional postal survey

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Reid Garth

2008-02-01

Full Text Available Abstract Background Men's lifestyles are generally less healthy than women's. This study identifies associations between health-related behaviour in different groups of men working in a Higher Education (HE institution. In addition, men were asked whether they regarded their health-related behaviours as a concern. This article highlights smoking, consumption of alcohol and physical activity as most common men's health-related lifestyle behaviours. Methods A descriptive cross-sectional survey was conducted among all male staff employed by a Higher Education institute in Scotland using a postal self-completed questionnaire. A total of 1,335 questionnaires were distributed and 501 were returned completed (38% return rate. The data were analysed using SPSS 13.0 for Windows. Results Less than 10% currently smoked and almost 44% of these smokers were light smokers. Marital status, job title, consumption of alcohol and physical activity level were the major factors associated with smoking behaviour. Men in manual jobs were far more likely to smoke. Nearly all (90% consumed alcohol, and almost 37% had more than recommended eight units of alcohol per day at least once a week and 16% had more than 21 units weekly. Younger men reported higher amount of units of alcohol on their heaviest day and per week. Approximately 80% were physically active, but less than 40% met the current Government guidelines for moderate physical activity. Most men wanted to increase their activity level. Conclusion There are areas of health-related behaviour, which should be addressed in populations of this kind. Needs assessment could indicate which public health interventions would be most appropriately aimed at this target group. However, the low response rate calls for some caution in interpreting our findings.

Cross-Cultural Investigation of Male Gait Perception in Relation to Physical Strength and Speed

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Bernhard Fink

2017-08-01

Full Text Available Previous research documents that men and women can accurately judge male physical strength from gait, but also that the sexes differ in attractiveness judgments of strong and weak male walkers. Women’s (but not men’s attractiveness assessments of strong male walkers are higher than for weak male walkers. Here, we extend this research to assessments of strong and weak male walkers in Chile, Germany, and Russia. Men and women judged videos of virtual characters, animated with the walk movements of motion-captured men, on strength and attractiveness. In two countries (Germany and Russia, these videos were additionally presented at 70% (slower and 130% (faster of their original speed. Stronger walkers were judged to be stronger and more attractive than weak walkers, and this effect was independent of country (but not sex. Women tended to provide higher attractiveness judgments to strong walkers, and men tended to provide higher attractiveness judgments to weak walkers. In addition, German and Russian participants rated strong walkers most attractive at slow and fast speed. Thus, across countries men and women can assess male strength from gait, although they tended to differ in attractiveness assessments of strong and weak male walkers. Attractiveness assessments of male gait may be influenced by society-specific emphasis on male physical strength.

Age-dependent male mating investment in Drosophila pseudoobscura.

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Sumit Dhole

Full Text Available Male mating investment can strongly influence fitness gained from a mating. Yet, male mating investment often changes with age. Life history theory predicts that mating investment should increase with age, and males should become less discriminatory about their mate as they age. Understanding age-dependent changes in male behavior and their effects on fitness is important for understanding how selection acts in age-structured populations. Although the independent effects of male or female age have been studied in many species, how these interact to influence male mating investment and fitness is less well understood. We mated Drosophila pseudoobscura males of five different age classes (4-, 8-, 11-, 15-, 19-day old to either young (4-day or old (11-day females, and measured copulation duration and early post-mating fecundity. Along with their independent effects, we found a strong interaction between the effects of male and female ages on male mating investment and fitness from individual matings. Male mating investment increased with male age, but this increase was more prominent in matings with young females. Male D. pseudoobscura made smaller investments when mating with old females. The level of such discrimination based on female age, however, also changed with male age. Intermediate aged males were most discriminatory, while the youngest and the oldest males did not discriminate between females of different ages. We also found that larger male mating investments resulted in higher fitness payoffs. Our results show that male and female ages interact to form a complex pattern of age-specific male mating investment and fitness.

[Inheritance of reversions to male fertility in male-sterile sorghum hybrids with 9E cytoplasm male sterility induced by environmental conditions].

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Elkonin, L A; Gerashchenkov, G A; Domanina, I V; Rozhnova, N A

2015-03-01

Heritable phenotypic alterations occurring during plant ontogenesis under the influence of environmental factors are among the most intriguing genetic phenomena. It was found that male-sterile sorghum hybrids in the 9E cytoplasm from the F1 and F2 generations, which were obtained by crossing CMS lines with different fertile lines grown in field conditions, were transferred to greenhouse produce fertile tillers. Lines created by the self-pollination of revertant tillers exhibit complete male fertility upon cultivation under various environments (in the field, Tdry plot,(y) Tirrigated plot(y)). In a number of test-crosses of revertants to CMS lines in the 9E cytoplasm, restoration of male fertility in F1 hybrids was found, indicating that revertants possess functional fertility-restoring genes. A high positive correlation was found between the fertility level of the test-cross hybrids and the hydrothermal coefficient (the ratio of the sum of precipitation to the sum of temperatures) during the booting stage and pollen maturation (r = 0.75...0.91; Pmale fertility are due to up-regulation of fertility-restoring genes by a high level of water availability. Comparative MSAP-analysis of DNA of male-sterile and male-fertile test-cross hybrids using HpaII/MspI restrictases and primers to polygalacturonase gene ADPG2, which is required for cell separation during reproductive development, and gene MYB46, the transcription factor regulating secondary wall biosynthesis, revealed differences in the number and the length of amplified fragments. Changes in the methylation of these genes in conditions of drought stress are apparently the reason for male sterility of sorghum hybrids in the 9E cytoplasm. These data demonstrate that methylation of nuclear genes in sterility-inducing cytoplasm may be one of mechanisms causing the CMS phenomenon.

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

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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.

Do pheromones reveal male immunocompetence?

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Rantala, Markus J; Jokinen, Ilmari; Kortet, Raine; Vainikka, Anssi; Suhonen, Jukka

2002-01-01

Pheromones function not only as mate attractors, but they may also relay important information to prospective mates. It has been shown that vertebrates can distinguish, via olfactory mechanisms, major histocompatibility complex types in their prospective mates. However, whether pheromones can transmit information about immunocompetence is unknown. Here, we show that female mealworm beetles (Tenebrio molitor) prefer pheromones from males with better immunocompetence, indicated by a faster encapsulation rate against a novel antigen, and higher levels of phenoloxidase in haemolymph. Thus, the present study indicates that pheromones could transmit information about males' parasite resistance ability and may work as a reliable sexual ornament for female choice. PMID:12204128

Differences in Performance between Male and Female Business Students.

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Hornaday, Robert W.; And Others

1989-01-01

A study analyzed the grade point averages (GPAs) and scores on a business concepts quiz of 419 undergraduate business students. Effect of student major was also controlled. Females earned higher overall grades than males; males outperformed females in ability to describe basic business concepts. Gender and academic major accounted for over 10…

‘It’s really a hard life’: Love, gender and HIV risk among male-to-female transgender persons

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MELENDEZ, RITA M.; PINTO, ROGÉRIO

2012-01-01

Scientific studies demonstrate high rates of HIV infection among male-to-female (MTF) transgender individuals and that stigma and discrimination place MTFs at increased risk for infection. However, there is little research examining how gender roles contribute to HIV risk. This paper reports on in-depth interviews with 20 MTFs attending a community clinic. Data reveal that stigma and discrimination create a heightened need for MTFs to feel safe and loved by a male companion and that in turn places them at a higher risk for acquiring HIV. Male-to-female transgender individuals appear to turn to men to feel loved and affirmed as women; their main HIV risk stems from their willingness to engage with sexual partners who provide a sense of love and acceptance but who also may also request unsafe sexual behaviours. A model illustrating how HIV risk is generated from stigma and discrimination is presented. PMID:17457728

Male reproductive health and environmental xenoestrogens

DEFF Research Database (Denmark)

Toppari, J; Larsen, J C; Christiansen, Peter

1996-01-01

that the adverse changes may be inter-related and have a common origin in fetal life or childhood. Exposure of the male fetus to supranormal levels of estrogens, such as diethlylstilbestrol, can result in the above-mentioned reproductive defects. The growing number of reports demonstrating that common......Male reproductive health has deteriorated in many countries during the last few decades. In the 1990s, declining semen quality has been reported from Belgium, Denmark, France, and Great Britain. The incidence of testicular cancer has increased during the same time incidences of hypospadias...... and cryptorchidism also appear to be increasing. Similar reproductive problems occur in many wildlife species. There are marked geographic differences in the prevalence of male reproductive disorders. While the reasons for these differences are currently unknown, both clinical and laboratory research suggest...

Male reproductive health and environmental xenoestrogens

DEFF Research Database (Denmark)

Toppari, J; Larsen, J C; Christiansen, Peter

1996-01-01

Male reproductive health has deteriorated in many countries during the last few decades. In the 1990s, declining semen quality has been reported from Belgium, Denmark, France, and Great Britain. The incidence of testicular cancer has increased during the same time incidences of hypospadias...... and cryptorchidism also appear to be increasing. Similar reproductive problems occur in many wildlife species. There are marked geographic differences in the prevalence of male reproductive disorders. While the reasons for these differences are currently unknown, both clinical and laboratory research suggest...... that the adverse changes may be inter-related and have a common origin in fetal life or childhood. Exposure of the male fetus to supranormal levels of estrogens, such as diethlylstilbestrol, can result in the above-mentioned reproductive defects. The growing number of reports demonstrating that common...

Supplementation of male pheromone on rock substrates attracts female rock lizards to the territories of males: a field experiment.

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José Martín

Full Text Available Many animals produce elaborated sexual signals to attract mates, among them are common chemical sexual signals (pheromones with an attracting function. Lizards produce chemical secretions for scent marking that may have a role in sexual selection. In the laboratory, female rock lizards (Iberolacerta cyreni prefer the scent of males with more ergosterol in their femoral secretions. However, it is not known whether the scent-marks of male rock lizards may actually attract females to male territories in the field.In the field, we added ergosterol to rocks inside the territories of male lizards, and found that this manipulation resulted in increased relative densities of females in these territories. Furthermore, a higher number of females were observed associated to males in manipulated plots, which probably increased mating opportunities for males in these areas.These and previous laboratory results suggest that female rock lizards may select to settle in home ranges based on the characteristics of scent-marks from conspecific males. Therefore, male rock lizards might attract more females and obtain more matings by increasing the proportion of ergosterol when scent-marking their territories. However, previous studies suggest that the allocation of ergosterol to secretions may be costly and only high quality males could afford it, thus, allowing the evolution of scent-marks as an honest sexual display.

Supplementation of Male Pheromone on Rock Substrates Attracts Female Rock Lizards to the Territories of Males: A Field Experiment

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Martín, José; López, Pilar

2012-01-01

Background Many animals produce elaborated sexual signals to attract mates, among them are common chemical sexual signals (pheromones) with an attracting function. Lizards produce chemical secretions for scent marking that may have a role in sexual selection. In the laboratory, female rock lizards (Iberolacerta cyreni) prefer the scent of males with more ergosterol in their femoral secretions. However, it is not known whether the scent-marks of male rock lizards may actually attract females to male territories in the field. Methodology/Principal Findings In the field, we added ergosterol to rocks inside the territories of male lizards, and found that this manipulation resulted in increased relative densities of females in these territories. Furthermore, a higher number of females were observed associated to males in manipulated plots, which probably increased mating opportunities for males in these areas. Conclusions/Significance These and previous laboratory results suggest that female rock lizards may select to settle in home ranges based on the characteristics of scent-marks from conspecific males. Therefore, male rock lizards might attract more females and obtain more matings by increasing the proportion of ergosterol when scent-marking their territories. However, previous studies suggest that the allocation of ergosterol to secretions may be costly and only high quality males could afford it, thus, allowing the evolution of scent-marks as an honest sexual display. PMID:22253895

The Priorities of Iranian Male Adolescents Health Needs.

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Zare, Elham; Simbar, Masoumeh; Shahhosseini, Zohreh; Alavi Majd, Hamid

2017-07-01

Health in the adolescence period guarantees the next generation's health. The assessment of health needs is the first stage for the implementation of health promotion interventions. This study aimed to assess the priorities of male adolescent's health needs in Tehran, Iran, in year 2015. This cross-sectional correlational study was conducted with 1,200 male adolescents aged between 13 and 18 years. Single male adolescents studying in public guidance and high schools in Tehran, Iran, in year 2015 were chosen using a random multistage sampling method. Data were collected using the male adolescent health need assessment scale. The data were analyzed using descriptive and inferential statistics. It was found that while the lowest score was for the domain of sexual health, other domains had average or higher than average scores. More attention should be paid to the sexual health needs of male adolescents. Policy makers need to design strategies that help meet the health needs of male adolescents.

Radiologic findings of male breast cancer: two cases report

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Chung, Soo Young; Kim, Sook Hyun; Bae, Sang Hoon; Ahn, Hye Kyung [Hallym University College of Medicine, Seoul (Korea, Republic of)

1993-09-15

Male breast cancer is very rare, with the incidence of 0.15-1% of all breast cancers and less than 1% of all cancers in men. The prognosis of male breast cancer is poorer than that of female because the median age of detection of the disease is in more late stage. It usually involves higher axillary lymph nodes. We report two case of male breast cancer to describe characteristic mammographic and ultrasonographic findings and to compare with the findings of gynaecomastia.

Chronic High Fat Diet Consumption Impairs Metabolic Health of Male Mice.

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Morselli, Eugenia; Criollo, Alfredo; Rodriguez-Navas, Carlos; Clegg, Deborah J

We show that chronic high fat diet (HFD) feeding affects the hypothalamus of male but not female mice. In our study we demonstrate that palmitic acid and sphingolipids accumulate in the central nervous system of HFD-fed males. Additionally, we show that HFD-feeding reduces proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) thus reducing estrogen receptor α (ERα) and driving hypothalamic inflammation in male but not female mice. Hypothalamic inflammation correlates with markers of metabolic dysregulation as indicated by dysregulation in glucose intolerance and myocardial function. Lastly, we demonstrate that there are blockages in mitophagy and lipophagy in hypothalamic tissues in males. Our data suggest there is a sexually dimorphic response to chronic HDF exposure, females; despite gaining the same amount of body weight following HFD-feeding, appear to be protected from the adverse metabolic effects of the HFD.

Cessation-related weight concern among homeless male and female smokers.

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Pinsker, Erika Ashley; Hennrikus, Deborah Jane; Erickson, Darin J; Call, Kathleen Thiede; Forster, Jean Lois; Okuyemi, Kolawole Stephen

2017-09-01

Concern about post-cessation weight gain is a barrier to making attempts to quit smoking; however, its effect on smoking cessation is unclear. In this study we examine cessation-related weight concern among the homeless, which hasn't been studied. Homeless males (n = 320) and females (n = 110) participating in a smoking cessation RCT in the Twin Cities, Minnesota from 2009 to 2011 completed surveys on cessation-related weight concern, smoking status, and components from the Behavioral Model for Vulnerable Populations. Generalized estimating equations were used to examine baseline predictors of cessation-related weight concern at baseline, the end of treatment, and 26-weeks follow-up. Logistic regression models were used to examine the relationship between cessation-related weight concern and smoking status at the end of treatment and follow-up. Females had higher cessation-related weight concern than males. Among males, older age, Black race, higher BMI, depression, and having health insurance were associated with higher cessation-related weight concern. Among females, nicotine dependence, greater cigarette consumption, indicating quitting is more important, older age of smoking initiation, and less support to quit from family were associated with higher cessation-related weight concern. In multivariate analyses, cessation-related weight concern decreased over time among females. Cessation-related weight concern wasn't associated with smoking cessation. Although several types of characteristics predicted cessation-related weight concern among males, only smoking characteristics predicted cessation-related weight concern among females. Given the small proportion of quitters in this study (8% of males and 5% of females), further research on the impact of cessation-related weight concern on smoking cessation among the homeless is warranted.

Long distance transport of irradiated male Glossina palpalis gambiensis pupae and its impact on sterile male yield

International Nuclear Information System (INIS)

Pagabeleguem, Soumaila; Seck, Momar Talla; Sall, Baba

2015-01-01

The application of the sterile insect technique (SIT) requires mass-production of sterile males of good biological quality. The size of the project area will in most cases determine whether it is more cost effective to produce the sterile flies locally (and invest in a mass-rearing facility) or import the sterile flies from a mass-rearing facility that is located in another country. This study aimed at assessing the effect of long distance transport of sterile male Glossina palpalis gambiensis pupae on adult male fly yield. The male pupae were produced at the Centre International de Recherche-Developpement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso, and shipped with a commercial courier service in insulated transport boxes at a temperature of ±10° to Senegal (36 h of transport). Upon arrival in the insectary in Dakar, the pupae were transferred to an emergence room and the flies monitored for 3-6 days. The results showed that the used system of isothermal boxes that contained phase change material packs (S8) managed to keep the temperature at around 10° which prevented male fly emergence during transport. The emergence rate was significantly higher for pupae from batch 2 (chilled at 4° for one day in the source insectary before transport) than those from batch 1 (chilled at 4° for two days in the source insectary before transport) i.e. an average (±sd) of 76.1 ± 13.2% and 72.2 ± 14.3%, respectively with a small proportion emerging during transport (0.7 ± 1.7% and 0.9 ± 2.9%, respectively). Among the emerged flies, the percentage with deformed (not fully expanded) wings was significantly higher for flies from batch 1 (12.0 ± 6.3%) than from batch 2 (10.7 ± 7.5%). The amount of sterile males available for release as a proportion of the total pupae shipped was 65.8 ± 13.3% and 61.7 ± 14.7% for batch 1 and 2 pupae, respectively. The results also showed that the temperature inside the parcel must be controlled around 10° with a

A role for 5alpha-reductase activity in the development of male homosexuality?

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Alias, A G

2004-12-01

Higher body hair with lower mesmorphism ratings were observed in Caucasian homosexual men compared with the general male population, reflecting elevated 5alpha-reductase (5alphaR) activity, and higher dihydrotestosterone-to-testosterone (DHT-to-T) ratio, in sharp contrast to 46,XY 5alphaR 2 deficiency subjects, who are often born with ambiguous, or female genitalia, but tend to grow up to be muscular, heterosexual men with very little body hair, or beard. One study also showed them scoring around dull normal IQs. A greater prevalence of liberal body hair growth in men with higher IQs and/or educational levels was also observed in several samples. The exceptions to this statistical trend are too unsettling, however. Nevertheless, the results of a number of published studies, including one showing higher DHT-to-T ratio in homosexual men, done with different objectives over a span of 80 years, together strongly support these findings. Furthermore, in an animal model, "cognitive-enhancing effects" of "5alpha-reduced androgen [metabolites]" were recently demonstrated.

Is patriarchy the source of men's higher mortality?

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Stanistreet, D; Bambra, C; Scott-Samuel, A

2005-01-01

Objective: To examine the relation between levels of patriarchy and male health by comparing female homicide rates with male mortality within countries. Hypothesis: High levels of patriarchy in a society are associated with increased mortality among men. Design: Cross sectional ecological study design. Setting: 51 countries from four continents were represented in the data—America, Europe, Australasia, and Asia. No data were available for Africa. Results: A multivariate stepwise linear regression model was used. Main outcome measure was age standardised male mortality rates for 51 countries for the year 1995. Age standardised female homicide rates and GDP per capita ranking were the explanatory variables in the model. Results were also adjusted for the effects of general rates of homicide. Age standardised female homicide rates and ranking of GDP were strongly correlated with age standardised male mortality rates (Pearson's r = 0.699 and Spearman's 0.744 respectively) and both correlations achieved significance (ppatriarchy, the higher is the rate of mortality among men. Conclusion: These data suggest that oppression and exploitation harm the oppressors as well as those they oppress, and that men's higher mortality is a preventable social condition, which could be tackled through global social policy measures. PMID:16166362

Honeybee males use highly concentrated nectar as fuel for mating flights.

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Hayashi, Masaki; Nakamura, Jun; Sasaki, Ken; Harano, Ken-Ichi

Honeybees use nectar held in the crop as their main source of energy for flight but the mass of the crop nectar load may be a cost burden. This study investigated whether males of the honeybee Apis mellifera adjust their nectar fuel load and concentration to enhance the success of mating flights. When the crop content was compared between males staying in the hive and those departing, the latter group had the larger volume (median, 5.0μl; range, 0.0-17.8μl) and higher concentration (median, 71.6%; range, 49.0%-77.6%), indicating that departing males load concentrated nectar as fuel before mating flights. Moreover, the crop nectar concentration was significantly higher in departing males than in departing workers. These results suggest that concentrated nectar is advantageous to males because it provides more sugar for energy at lower mass and secures longer or more effective mating flights for higher chance of reproductive success. No significant effect of age was detected in crop volume, and concentration and amount of dissolved sugars in the crop content. In addition, laboratory experiments showed that males had only about 5μl of nectar in the crop soon after feeding, irrespective of fed volume (5-15μl), suggesting they do not hold much nectar in the crop but send it rapidly to the midgut, unlike workers. Copyright © 2016 Elsevier Ltd. All rights reserved.

Clinical trials in male hormonal contraception.

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Nieschlag, Eberhard

2010-11-01

Research has established the principle of hormonal male contraception based on suppression of gonadotropins and spermatogenesis. All hormonal male contraceptives use testosterone, but only in East Asian men can testosterone alone suppress spermatogenesis to a level compatible with contraceptive protection. In Caucasians, additional agents are required of which progestins are favored. Clinical trials concentrate on testosterone combined with norethisterone, desogestrel, etonogestrel or depot-medroxyprogesterone acetate. The first randomized, placebo-controlled clinical trial performed by the pharmaceutical industry demonstrated the effectiveness of a combination of testosterone undecanoate and etonogestrel in suppressing spermatogenesis in volunteers. Copyright © 2010 Elsevier Inc. All rights reserved.

Sex and aggregation pheromone transport after methyl eugenol consumption in male Bactrocera papayae

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Hee, Alvin K.W.; Tan, K.H.

2000-01-01

Amongst at least 52 sibling species complexes in the Oriental fruit fly, Bactrocera dorsalis Hendel (Diptera: Tephritidae), B. papayae (formerly Mal B) Drew and Hancock (Drew and Hancock 1994) is beginning to emerge as an economically important insect pest which poses a severe threat to the fruit cultivation in both subtropical and tropical countries. In Malaysia, B. papayae is one of the most damaging pests which infests many commercially grown fruits (Tan and Lee 1982). Like the Oriental fruit fly and its sibling species complex, B. carambolae Drew and Hancock, B. papayae is also strongly attracted to, and compulsively feeds on, methyl eugenol (ME) (Tan 1993). Chemical analyses revealed that in B. papayae males, ME is converted to phenylpropanoids which are then selectively accumulated in the rectal gland. Of the three major volatile substances, 2-allyl-4,5-dimethoyphenol (allyl-DMP) was detected in higher quantities relative to the trans-coniferyl alcohol (4-(3-hydroxy-E-propenyl)-2-methoxyphenol) (CF) and cis-3,4-dimethoxycinnamyl alcohol (cis-DMC) (Nishida et al. 1988a, 1988b). Behavioural studies have also shown that allyl-DMP and CF function as male sex and aggregation pheromone in B. papayae (Tan and Nishida 1996, Hee and Tan 1998). Allyl-DMP was found to be the most attractive compound and cis-DMC the least attractive to the males (Tan 1996). Consumption of ME enhances the mating competitiveness of males. This is demonstrated by the strong attraction of females to conspecific ME-fed males in wind tunnel experiments (Hee and Tan 1998). In male-male mating competition for virgin females, males that fed on ME performed significantly better (Shelly and Dewire 1994, Tan and Nishida 1996). Thus it appears that ME-fed males produced signals that were more attractive. However, the characterisation and understanding of the functions of these phenylpropanoids have not been accompanied by studies of their physiological mode of transport in male flies. The current

African American Male College Students Navigate to Achieve: The Relationship among College Adjustment Experiences, Coping, and GPA for Black Males at Two Predominantly White Institutions

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Walters, Sabrina Denise

2017-01-01

African American males face daunting obstacles as they pursue higher education as research has shown. This study sought to better understand the impact of specific factors--social support, racial identity, perceived racial discrimination, coping, and religious coping--on the academic achievement of African American male college student…

Corticosteroid receptor expression in a teleost fish that displays alternative male reproductive tactics.

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Arterbery, Adam S; Deitcher, David L; Bass, Andrew H

2010-01-01

Corticosteroid signaling mechanisms mediate a wide range of adaptive physiological responses, including those essential to reproduction. Here, we investigated the presence and relative abundance of corticosteroid receptors during the breeding season in the plainfin midshipman fish (Porichthys notatus), a species that has two male reproductive morphs. Only type I "singing" males acoustically court females and aggressively defend a nest site, whereas type II "sneaker" males steal fertilizations from nesting type I males. Cloning and sequencing first identified glucocorticoid (GR) and mineralocorticoid (MR) receptors in midshipman that exhibited high sequence identity with other vertebrate GRs and MRs. Absolute-quantitative real-time PCR then revealed higher levels of GR in the central nervous system (CNS) of type II males than type I males and females, while GR levels in the sound-producing, vocal muscle and the liver were higher in type I males than type II males and females. MR expression was also greater in the CNS of type II males than type I males or females, but the differences were more modest in magnitude. Lastly, plasma levels of cortisol, the main glucocorticoid in teleosts, were 2- to 3-fold greater in type II males compared to type I males. Together, the results suggest a link between corticosteroid regulation and physiological and behavioral variation in a teleost fish that displays male alternative reproductive tactics.

Ontogenetically-regulated male sterility in tissue culture - induced and spontaneous sorghum mutants

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Elkonin L.A.

2003-01-01

Full Text Available Variability of male fertility expression in the AS-1 line, a somaclonal variant obtained from tissue culture of CMS-plant, and in the progeny of revenant '124-1' obtained from fertile tiller, which developed on CMS-plant transferred from the field to the greenhouse, was investigated. Both revertants were characterized by similar expression of male fertility during plant ontogenesis: the panicle on the main tiller was almost completely sterile whereas formation of fertile pollen grains and seed set were observed on the panicles of the shoot tillers. A clear basipetal gradient of male fertility was manifested on all panicles: the base had significantly higher per cent of fertile pollen grains in comparison with the middle part, while in the top the anthers were either absent or had few sterile pollen grains. Such an ontogenetically-regulated restoration of male fertility was controlled by nuclear genes and could be transferred through the pollen in crosses with progenitor CMS-line. Growing of AS-1 plants in the growth chambers simultaneously under a long (16/8 and a short (12/12 daylength conditions demonstrated that differences of fertility level in different tillers was not caused by change of photoperiod during plant ontogenesis and functioning of photoperiod-sensitive fertility restoring gene. Whereas, the ontogenetically-regulated expression of male fertility in both revenants was temperature-dependent and was clearly manifested under relatively cool conditions during 2-week period before the beginning of anthesis of the first panicle (average daily temperature 21°C. The increase of the average daily temperature by 2-3 С resulted in sharp increase of male fertility level. Possibility of using AS-1 line in a new "two-line system" of hybrid seed production, which require only two lines (sterile mutant and fertility restorer, is discussed.

Do knowledge and cultural perceptions of modern female contraceptives predict male involvement in Ayete, Nigeria?

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Sanusi, A; Akinyemi, Oluwaseun O; Onoviran, Oghemetega O

2014-12-01

Male involvement is crucial to female contraceptive use. This study examined how male knowledge and cultural perceptions of modern female contraceptives influence involvement in contraceptive use. A cross-sectional survey of 389 men from Ayete, Nigeria was used to regress a continuous male involvement score on demographic variables, knowledge of at least one method of modern female contraception and a scored male perception variable using Ordinary Least Squares regression. Controlling for perception, the knowledge of at least one method of modern female contraception was not significantly associated with a change in male involvement (p=0.264). Increasing positive perception was associated with higher male involvement scores (p=0.001). Higher educated males, those with a current desire to have children and males whose partners were currently using a method had greater male involvement scores (pcultural perceptions, in addition to providing in-depth knowledge of contraceptive methods.

Testosterone and reproductive effort in male primates.

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Muller, Martin N

2017-05-01

Considerable evidence suggests that the steroid hormone testosterone mediates major life-history trade-offs in vertebrates, promoting mating effort at the expense of parenting effort or survival. Observations from a range of wild primates support the "Challenge Hypothesis," which posits that variation in male testosterone is more closely associated with aggressive mating competition than with reproductive physiology. In both seasonally and non-seasonally breeding species, males increase testosterone production primarily when competing for fecund females. In species where males compete to maintain long-term access to females, testosterone increases when males are threatened with losing access to females, rather than during mating periods. And when male status is linked to mating success, and dependent on aggression, high-ranking males normally maintain higher testosterone levels than subordinates, particularly when dominance hierarchies are unstable. Trade-offs between parenting effort and mating effort appear to be weak in most primates, because direct investment in the form of infant transport and provisioning is rare. Instead, infant protection is the primary form of paternal investment in the order. Testosterone does not inhibit this form of investment, which relies on male aggression. Testosterone has a wide range of effects in primates that plausibly function to support male competitive behavior. These include psychological effects related to dominance striving, analgesic effects, and effects on the development and maintenance of the armaments and adornments that males employ in mating competition. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparison of male and female foot shape.

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Luo, Gangming; Houston, Vern L; Mussman, Martin; Garbarini, Maryanne; Beattie, Aaron C; Thongpop, Chaiya

2009-01-01

Morphological and geometric differences between male and female feet can be the decisive factor of whether well-fitting, functional, and comfortable footwear is available for both men and women. Optical scans, plaster wrap casts, and a set of manual measurements from the right feet of 51 female participants, aged 20 to 59 years (32 +/- 10.2 years), and 39 male participants, aged 22 to 71 years (47.1 +/- 12.1 years), were taken to determine which parameters were the most significant in characterizing pedal geometry and which had the largest difference between male and female feet. Analysis showed that the heel-to-ball length (ball length) of the male participants' feet (181.5 mm) was significantly longer, on average, than that of the female participants' feet (165.0 mm). The width of the male paticipants' feet at the ball, instep, and heel regions, as well as the ball circumference, normalized by the ball length, were all significantly larger on average, than the female test participants' feet. However, toe region, instep, and medial and lateral malleoli heights were larger, on average, for the female participants than for the male. The results show that female feet differ in size and shape from male feet and are not algebraically scaled, smaller versions of male feet, as is often assumed. The study shows that the average male participants' feet are longer than that of the female participants' feet, while the female feet are relatively narrower but higher than those of the male participants.

Safety assessment of Hibiscus sabdariffa after maternal exposure on male reproductive parameters in rats.

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de Arruda, Aline; Cardoso, Claudia Andrea L; Vieira, Maria do Carmo; Arena, Arielle Cristina

2016-01-01

Hibiscus sabdariffa L. (Malvaceae) is a species widely used in folk medicine for the treatment of some disorders. This study evaluated the effects of H. sabdariffa (HS) on the development of the male reproductive tract in rats following in utero exposure. Pregnant rats received 250 or 500 mg/kg of HS extract or vehicle from gestational day 12 until day 21 of lactation. Both doses of HS increased the body weight of male offspring at weaning, without compromising the puberty onset parameters. At puberty, there was a significant increase in the vas deferens absolute weight and a significant reduction in the relative weight of kidney at higher dose. These animals also presented a significant reduction in the sperm number in the caput/corpus of epididymis after exposure to both doses and a reduction in the sperm number in the cauda epididymis for the lower dose. At adulthood, the highest dose significantly reduced the sperm production in relation to controls and both doses provoked a reduction in the relative sperm number in the epididymis without affecting the sperm morphology. These findings demonstrated that maternal exposure to H. sabdariffa can adversely influence the male reproductive system in rats.

Women Technology Leaders: Gender Issues in Higher Education Information Technology

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Drury, Marilyn

2011-01-01

Women working in higher education information technology (IT) organizations and those seeking leadership positions in these organizations face a double challenge in overcoming the traditionally male-dominated environments of higher education and IT. Three women higher education chief information officers (CIOs) provided their perspectives,…

Improving voluntary medical male circumcision standards ...

African Journals Online (AJOL)

Voluntary medical male circumcision (VMMC) has been demonstrated to reduce the transmission of HIV by 60%. Scaling up VMMC services requires that they be of high quality, socially accepted, and effective. We evaluated an intervention aimed at improving VMMC standards adherence and patient follow-up rates in nine ...

Reversible, non-barrier male contraception: status and prospects.

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Hoesl, C E; Saad, F; Pöppel, M; Altwein, J E

2005-11-01

Male, non-barrier, contraceptive options are limited to vasectomy and inadequate methods such as withdrawal and periodic abstinence. Herein we give an overview of current research on male contraception by pharmacological means. Literature search of PubMed documented publications and abstracts from meetings. Cross-cultural surveys show men's willingness to carry contraceptive responsibility. Clinical trials substantiate that hormonal contraception involving suppression of gonadotropins holds the best promise to provide a male pharmacological contraceptive. Androgens have been demonstrated to induce reversible infertility particularly in combination with certain progestins and GnRH antagonists. Advances in non-endocrine contraception include intervention with triptolide derivatives, alkylated imino sugars, and immunization by eppin. The prospect of a pharmacological, male contraceptive has been considerably advanced in recent years. Long-term studies involving a greater number of subjects may result in a safe, reversible and effective means. Asia is likely to be the first market for male, hormonal contraceptive methods. The clinical evaluation of non-endocrine approaches may ultimately lead to an alternative to hormone-based male contraception.

Brain Transcriptional Profiles of Male Alternative Reproductive Tactics and Females in Bluegill Sunfish.

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Partridge, Charlyn G; MacManes, Matthew D; Knapp, Rosemary; Neff, Bryan D

2016-01-01

Bluegill sunfish (Lepomis macrochirus) are one of the classic systems for studying male alternative reproductive tactics (ARTs) in teleost fishes. In this species, there are two distinct life histories: parental and cuckolder, encompassing three reproductive tactics, parental, satellite, and sneaker. The parental life history is fixed, whereas individuals who enter the cuckolder life history transition from sneaker to satellite tactic as they grow. For this study, we used RNAseq to characterize the brain transcriptome of the three male tactics and females during spawning to identify gene ontology (GO) categories and potential candidate genes associated with each tactic. We found that sneaker males had higher levels of gene expression differentiation compared to the other two male tactics. Sneaker males also had higher expression in ionotropic glutamate receptor genes, specifically AMPA receptors, compared to other males, which may be important for increased spatial working memory while attempting to cuckold parental males at their nests. Larger differences in gene expression also occurred among male tactics than between males and females. We found significant expression differences in several candidate genes that were previously identified in other species with ARTs and suggest a previously undescribed role for cAMP-responsive element modulator (crem) in influencing parental male behaviors during spawning.

The male handicap: male-biased mortality explains skewed sex ratios in brown trout embryos.

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Morán, P; Labbé, L; Garcia de Leaniz, C

2016-12-01

Juvenile sex ratios are often assumed to be equal for many species with genetic sex determination, but this has rarely been tested in fish embryos due to their small size and absence of sex-specific markers. We artificially crossed three populations of brown trout and used a recently developed genetic marker for sexing the offspring of both pure and hybrid crosses. Sex ratios (SR = proportion of males) varied widely one month after hatching ranging from 0.15 to 0.90 (mean = 0.39 ± 0.03). Families with high survival tended to produce balanced or male-biased sex ratios, but SR was significantly female-biased when survival was low, suggesting that males sustain higher mortality during development. No difference in SR was found between pure and hybrid families, but the existence of sire × dam interactions suggests that genetic incompatibility may play a role in determining sex ratios. Our findings have implications for animal breeding and conservation because skewed sex ratios will tend to reduce effective population size and bias selection estimates. © 2016 The Authors.

Behavioral and physiological polymorphism in males of the austral lizard Liolaemus sarmientoi.

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Fernández, Jimena B; Bastiaans, Elizabeth; Medina, Marlin; Méndez De la Cruz, Fausto R; Sinervo, Barry R; Ibargüengoytía, Nora R

2018-02-01

Integrative behavioral studies show that the interplay between individual physiology and social behavior influences the ecology of the species, ultimately affecting individual fitness. Particularly in lizards, color polymorphism is associated with differential behaviors and reproductive strategies, which are evident in mature males during the mating season. Dominant males generally have greater endurance, higher body temperature, and larger bodies than submissive males, so they can acquire and defend larger territories and have greater access to females for mating. We studied whether the color morphs observed in males of one of the world's southernmost reptiles, Liolaemus sarmientoi, are related to behavioral variation during agonistic interactions, thermal physiology, morphology, and/or locomotor stamina. Liolaemus sarmientoi males exhibit three color morphs: red (RR), red-yellow (RY), and yellow (YY). These lizards exhibit subtle behavioral displays and we did not observe stamina differences among morphs. However, we found that RR males are more aggressive than YY males during agonistic encounters. In addition, greater body temperature change during trials, higher field body temperatures, and greater head sizes of RR males compared to RY or YY indicate that RR is a dominant morph, which may influence their ability to acquire and defend territory and tactics for achieving reproductive success.

Heightened aggression and winning contests increase corticosterone but decrease testosterone in male Australian water dragons.

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Baird, Troy A; Lovern, Matthew B; Shine, Richard

2014-07-01

Water dragons (Intellegama [Physignathus] lesueurii) are large (to >1m) agamid lizards from eastern Australia. Males are fiercely combative; holding a territory requires incessant displays and aggression against other males. If a dominant male is absent, injured or fatigued, another male soon takes over his territory. Our sampling of blood from free-ranging adult males showed that baseline levels of both testosterone and corticosterone were not related to a male's social tactic (territorial versus non-territorial), or his frequency of advertisement display, aggression, or courtship behavior. Even when we elicited intense aggression by non-territorial males (by temporarily removing territory owners), testosterone did not increase with the higher levels of aggression that ensued. Indeed, testosterone levels decreased in males that won contests. In contrast, male corticosterone levels increased with the heightened aggression during unsettled conditions, and were higher in males that won contests. High chronic male-male competition in this dense population may favor high testosterone levels in all adult males to facilitate advertisement and patrol activities required for territory maintenance (by dominant animals), and to maintain readiness for territory take-overs (in non-territorial animals). Corticosterone levels increased in response to intense aggression during socially unstable conditions, and were higher in contest winners than losers. A positive correlation between the two hormones during socially unstable conditions suggests that the high stress of contests decreased androgen production. The persistent intense competition in this population appears to exact a high physiological cost, which together with our observation that males sometimes lose their territories to challengers may indicate cycling between these two tactics to manage long-term energetic costs. Copyright © 2014 Elsevier Inc. All rights reserved.

The Needs of Male Visuality: The Rhetoric of Male Gaze in Snuff and Hard-Core Culture between Cinema and Literature

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Mirko Lino

2014-06-01

-  Social and cultural: the need of having to re-establish male dominance against the destructuring action of feminism. The field of analysis of cinematographic and literary outputs is focused on two titles: Snuff (1976 a movie produced by A. Shackleton, and the novel Snuff (2008 by Chuck Palahniuk. The movie is useful for the description of a snuff aesthetic and the rhetoric of male gaze; the novel instead is useful for the identification of relevant features about gender questions applied to extreme hard core pornography. At the end, it will be demonstrated the political attempt to reverse the hegemonic rhetoric of male gaze acting directly on the aesthetic of snuff movie ritual.

Wing Morphometry and Acoustic Signals in Sterile and Wild Males: Implications for Mating Success in Ceratitis capitata

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João Maria Gomes Alencar de Souza

2015-01-01

Full Text Available The sterile insect technique (SIT is widely utilized in the biological control of fruit flies of the family Tephritidae, particularly against the Mediterranean fruit fly. This study investigated the interaction between mating success and morphometric variation in the wings and the production of acoustic signals among three male groups of Ceratitis capitata (Wiedemann: (1 wild males, (2 irradiated with Co-60 (steriles, and (3 irradiated (steriles and treated with ginger oil. The canonical variate analysis discriminated two groups (males irradiated and males wild, based on the morphological shape of the wings. Among males that emit buzz signals, wild males obtained copulation more frequently than males in Groups 2 and 3. The individuals of Group 3 achieved more matings than those in Group 2. Wild males displayed lower pulse duration, higher intervals between pulses, and higher dominant frequency. Regarding the reproductive success, the morphological differences in the wings’ shape between accepted and nonaccepted males are higher in wild males than in the irradiated ones. The present results can be useful in programs using the sterile insect technique for biological control of C. capitata.

The population dynamical implications of male-biased parasitism in different mating systems.

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Martin R Miller

2007-07-01

Full Text Available Although there is growing evidence that males tend to suffer higher levels of parasitism than females, the implications of this for the population dynamics of the host population are not yet understood. Here we build on an established 'two-sex' model and investigate how increased susceptibility to infection in males affects the dynamics, under different mating systems. We investigate the effect of pathogenic disease at different case mortalities, under both monogamous and polygynous mating systems. If the case mortality is low, then male-biased parasitism appears similar to unbiased parasitism in terms of its effect on the population dynamics. At higher case mortalities, we identified significant differences between male-biased and unbiased parasitism. A host population may therefore be differentially affected by male-biased and unbiased parasitism. The dynamical outcome is likely to depend on a complex interaction between the host's mating system and demography, and the parasite virulence.

Triadic male-infant-male interaction serves in bond maintenance in male Assamese macaques.

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Josefine Kalbitz

Full Text Available While the ultimate consequences of social bonds start to be better understood, the proximate behavioural mechanisms underlying the formation and maintenance of these close affiliative relationships have received less attention. We investigated the possible function of male-infant-male interactions (MIMIs in male-male social bonding processes by analysing about 9000h of focal animal observations collected on two groups of wild Assamese macaques. In support of an agonistic buffering function of MIMIs, after engaging in a MIMI upon approach, subordinates stayed longer in close proximity of a dominant male. Overall, the frequency of MIMIs increased the stronger the affiliative relationship between two males, suggesting that MIMIs like grooming function in relationship maintenance. We did not find support for a role of MIMIs in bond formation as the frequency of MIMIs did not affect the time a male dyad spent in proximity in the consecutive year. Our results contribute to the general debate on behaviours influencing social dynamics in group living mammals.

A demonstration of mobile phone deployment to support the ...

African Journals Online (AJOL)

A demonstration of mobile phone deployment to support the treatment of acutely ill children under five in Bushenyi district, Uganda. Jerome Kabakyenga, Celestine Barigye, Jennifer Brenner, Samuel Maling, Denise Buchner, Alberto Nettle-Aquirre, Nalini Singhal, Teddy Kyomuhangi, David Tumusiime, Janet Finch, Stuart ...

Costs and Benefits to Pregnant Male Pipefish Caring for Broods of Different Sizes.

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Sagebakken, Gry; Ahnesjö, Ingrid; Kvarnemo, Charlotta

2016-01-01

Trade-offs between brood size and offspring size, offspring survival, parental condition or parental survival are classic assumptions in life history biology. A reduction in brood size may lessen these costs of care, but offspring mortality can also result in an energetic gain, if parents are able to utilize the nutrients from the demised young. Males of the broad-nosed pipefish (Syngnathus typhle) care for the offspring by brooding embryos in a brood pouch. Brooding males can absorb nutrients that emanate from embryos, and there is often a reduction in offspring number over the brooding period. In this study, using two experimentally determined brood sizes (partially and fully filled brood pouches), we found that full broods resulted in larger number of developing offspring, despite significantly higher absolute and relative embryo mortality, compared to partial broods. Male survival was also affected by brood size, with males caring for full broods having poorer survival, an effect that together with the reduced embryo survival was found to negate the benefit of large broods. We found that embryo mortality was lower when the brooding males were in good initial condition, that embryos in broods with low embryo mortality weighed more, and surprisingly, that males in higher initial condition had embryos of lower weight. Brood size, however, did not affect embryo weight. Male final condition, but not initial condition, correlated with higher male survival. Taken together, our results show costs and benefits of caring for large brood sizes, where the numerical benefits come with costs in terms of both embryo survival and survival of the brooding father, effects that are often mediated via male condition.

Costs and Benefits to Pregnant Male Pipefish Caring for Broods of Different Sizes.

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Gry Sagebakken

Full Text Available Trade-offs between brood size and offspring size, offspring survival, parental condition or parental survival are classic assumptions in life history biology. A reduction in brood size may lessen these costs of care, but offspring mortality can also result in an energetic gain, if parents are able to utilize the nutrients from the demised young. Males of the broad-nosed pipefish (Syngnathus typhle care for the offspring by brooding embryos in a brood pouch. Brooding males can absorb nutrients that emanate from embryos, and there is often a reduction in offspring number over the brooding period. In this study, using two experimentally determined brood sizes (partially and fully filled brood pouches, we found that full broods resulted in larger number of developing offspring, despite significantly higher absolute and relative embryo mortality, compared to partial broods. Male survival was also affected by brood size, with males caring for full broods having poorer survival, an effect that together with the reduced embryo survival was found to negate the benefit of large broods. We found that embryo mortality was lower when the brooding males were in good initial condition, that embryos in broods with low embryo mortality weighed more, and surprisingly, that males in higher initial condition had embryos of lower weight. Brood size, however, did not affect embryo weight. Male final condition, but not initial condition, correlated with higher male survival. Taken together, our results show costs and benefits of caring for large brood sizes, where the numerical benefits come with costs in terms of both embryo survival and survival of the brooding father, effects that are often mediated via male condition.

When not to copy: female fruit flies use sophisticated public information to avoid mated males

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Loyau, Adeline; Blanchet, Simon; van Laere, Pauline; Clobert, Jean; Danchin, Etienne

2012-10-01

Semen limitation (lack of semen to fertilize all of a female's eggs) imposes high fitness costs to female partners. Females should therefore avoid mating with semen-limited males. This can be achieved by using public information extracted from watching individual males' previous copulating activities. This adaptive preference should be flexible given that semen limitation is temporary. We first demonstrate that the number of offspring produced by males Drosophila melanogaster gradually decreases over successive copulations. We then show that females avoid mating with males they just watched copulating and that visual public cues are sufficient to elicit this response. Finally, after males were given the time to replenish their sperm reserves, females did not avoid the males they previously saw copulating anymore. These results suggest that female fruit flies may have evolved sophisticated behavioural processes of resistance to semen-limited males, and demonstrate unsuspected adaptive context-dependent mate choice in an invertebrate.

A Comparative Study of Factors Influencing Male and Female Lecturers' Job Satisfaction in Ghanaian Higher Education

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Amos, Patricia Mawusi; Acquah, Sakina; Antwi, Theresa; Adzifome, Nixon Saba

2015-01-01

The study sought to compare factors influencing male and female lecturers' job satisfaction. Cross-sectional survey designs employing both quantitative and qualitative approaches were adopted for the study. Simple random sampling was used to select 163 lecturers from the four oldest public universities in Ghana. Celep's (2000) Organisational…

The dynamics of male-male competition in Cardiocondyla obscurior ants

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Cremer Sylvia

2012-06-01

Full Text Available Abstract Background The outcome of male-male competition can be predicted from the relative fighting qualities of the opponents, which often depend on their age. In insects, freshly emerged and still sexually inactive males are morphologically indistinct from older, sexually active males. These young inactive males may thus be easy targets for older males if they cannot conceal themselves from their attacks. The ant Cardiocondyla obscurior is characterised by lethal fighting between wingless (“ergatoid” males. Here, we analyse for how long young males are defenceless after eclosion, and how early adult males can detect the presence of rival males. Results We found that old ergatoid males consistently won fights against ergatoid males younger than two days. Old males did not differentiate between different types of unpigmented pupae several days before emergence, but had more frequent contact to ready-to-eclose pupae of female sexuals and winged males than of workers and ergatoid males. In rare cases, old ergatoid males displayed alleviated biting of pigmented ergatoid male pupae shortly before adult eclosion, as well as copulation attempts to dark pupae of female sexuals and winged males. Ergatoid male behaviour may be promoted by a closer similarity of the chemical profile of ready-to-eclose pupae to the profile of adults than that of young pupae several days prior to emergence. Conclusion Young ergatoid males of C. obscurior would benefit greatly by hiding their identity from older, resident males, as they are highly vulnerable during the first two days of their adult lives. In contrast to the winged males of the same species, which are able to prevent ergatoid male attacks by chemical female mimicry, young ergatoids do not seem to be able to produce a protective chemical profile. Conflicts in male-male competition between ergatoid males of different age thus seem to be resolved in favour of the older males. This might represent selection

Toward Male Individualization with Rapidly Mutating Y-Chromosomal Short Tandem Repeats

DEFF Research Database (Denmark)

Ballantyne, Kaye N; Ralf, Arwin; Aboukhalid, Rachid

2014-01-01

diversity was increased in 86% of the populations tested and overall male relative differentiation was raised by 23.5%. Our study demonstrates the value of RM Y-STRs in identifying and separating unrelated and related males and provides a reference database. This article is protected by copyright. All...

Noninvasive Body Contouring: A Male Perspective.

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Wat, Heidi; Wu, Douglas C; Goldman, Mitchel P

2018-01-01

Noninvasive body contouring is an attractive therapeutic modality to enhance the ideal male physique. Men place higher value on enhancing a well-defined, strong, masculine jawline and developing a V-shaped taper through the upper body. An understanding of the body contour men strive for allows the treating physician to focus on areas that are of most concern to men, thus enhancing patient experience and satisfaction. This article discusses noninvasive body contouring techniques, taking into account the unique aesthetic concerns of the male patient by combining an analysis of the existing literature with our own clinical experience. Copyright © 2017 Elsevier Inc. All rights reserved.

Masculine beliefs, parental communication, and male adolescents' health care use.

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Marcell, Arik V; Ford, Carol A; Pleck, Joseph H; Sonenstein, Freya L

2007-04-01

Male adolescents frequently become disconnected from health care, especially as they get older, which limits physicians' abilities to address their health needs and results in missed opportunities to connect them to the health care system as they enter adulthood. In this study we tested the ability of modifiable (beliefs about masculinity, parental communication, sex education, and health insurance) and nonmodifiable (age, race/ethnicity, and region of residence) factors to prospectively predict health care use by male adolescents. We conducted a prospective analysis of data from 1677 male participants aged 15 to 19 years who completed the National Survey of Adolescent Males, a household probability survey conducted throughout the United States in 1988 (wave 1, participation rate: 74%) and in 1990-1991 (wave 2, follow-up rate: 89%). We present percentages and adjusted relative risks of the factors that predict male adolescents' self-report of a physical examination by a regular provider in the past year measured at wave 2. On average, 1067 (66%) of 1677 male adolescents at wave 2 reported having a physical examination within the last year. Factors associated with a lower likelihood of a physical examination included living in the South, Midwest, and West; being older in age; and holding more traditional masculine beliefs. Factors associated with a higher likelihood of a physical examination included communicating about reproductive health with both parents and being insured. Male adolescents who were sexually active or engaged in > or = 2 other risk behaviors had neither a higher nor lower likelihood of a physical examination. Efforts to enhance male adolescents' health through health care should include work to modify masculine stereotypes, improve mothers' and fathers' communication about health with their sons, expand health insurance coverage, and identify interventions to connect male adolescents at increased risk for health problems with health care.

Male-to-male sex among men who inject drugs in Delhi, India: overlapping HIV risk behaviours.

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Armstrong, Gregory; Jorm, Anthony F; Samson, Luke; Joubert, Lynette; Singh, Shalini; Kermode, Michelle

2015-04-01

HIV among people who inject drugs (PWID) is a major public health challenge in India. This paper examines PWID in Delhi who also have male-to-male sex with a focus on overlapping HIV risk behaviours and the psychosocial correlates of a history of male-to-male anal sex. We analysed data collected in April-May of 2012 from a community-based sample of 420 male PWID in Delhi obtained using time location sampling. One third (37%) of the men reported a history of anal sex with men, among whom just 16% used a condom at last anal sex. Almost all (93%) participants who had a history of anal sex with men also had sex with women. Chi-square tests revealed that a history of anal sex with men was associated with a higher number of female sexual partners and sharing of needles and syringes. Additionally, unprotected sex at last sex with a male partner was significantly associated with unprotected sex at last sex with regular and paid female partners. Multivariate binary logistic regression revealed that the psychosocial correlates of a history of anal sex with other men were: being aged 18-24 (OR = 2.4, p = 0.014), illiteracy (OR = 1.9, p = 0.033), having never been married (OR = 2.6, p = 0.007), a main source of income of crime/begging (OR = 3.1, p = 0.019), a duration of injecting drug use greater than 20 years (OR = 3.4, p = 0.035) and suicidal ideation (OR = 1.7, p = 0.048). Male-to-male sex was associated with psychosocial vulnerability, including a longer history of injecting drug use, suicidal ideation and socio-economic disadvantage. Given the extent of overlapping HIV risk behaviours, HIV programs for PWID would benefit from a strong focus on prevention of sexual HIV transmission, especially among male injectors who also have sex with other men. Copyright © 2014 Elsevier B.V. All rights reserved.

The weaker sex? The propensity for male-biased piglet mortality.

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Emma M Baxter

Full Text Available For the most part solutions to farm animal welfare issues, such as piglet mortality, are likely to lie within the scientific disciplines of environmental design and genetic selection, however understanding the ecological basis of some of the complex dynamics observed between parent and offspring could make a valuable contribution. One interesting, and often discussed, aspect of mortality is the propensity for it to be sex-biased. This study investigated whether known physiological and behavioural indicators of piglet survival differed between the sexes and whether life history strategies (often reported in wild or feral populations relating to parental investment were being displayed in a domestic population of pigs. Sex ratio (proportion of males (males/males+females at birth was 0.54 and sex allocation (maternal investment measured as piglet birth weight/litter weight was statistically significantly male-biased at 0.55 (t(35 = 2.51 P = 0.017, suggesting that sows invested more in sons than daughters during gestation. Despite this investment in birth weight, a known survival indicator, total pre-weaning male mortality was statistically significantly higher than female mortality (12% vs. 7% respectively z = 2.06 P = 0.040. Males tended to suffer from crushing by the sow more than females and statistically significantly more males died from disease-related causes. Although males were born on average heavier, with higher body mass index and ponderal index, these differences were not sustained. In addition male piglets showed impaired thermoregulation compared to females. These results suggest male-biased mortality exists despite greater initial maternal investment, and therefore reflects the greater susceptibility of this sex to causal mortality factors. Life history strategies are being displayed by a domestic population of pigs with sows in this study displaying a form of parental optimism by allocating greater resources at birth

Male reproductive competition in spawning aggregations of cod ( Gadus morhua , L.)

DEFF Research Database (Denmark)

Bekkevold, Dorte; Hansen, Michael Møller; Loeschcke, V.

2002-01-01

Reproductive competition may lead to a large skew in reproductive success among individuals. Very few studies have analysed the paternity contribution of individual males in spawning aggregations of fish species with huge census population sizes. We quantified the variance in male reproductive...... success in spawning aggregations of cod under experimental conditions over an entire spawning season. Male reproductive success was estimated by microsatellite-based parentage analysis of offspring produced in six separate groups of spawning cod. In total, 1340 offspring and 102 spawnings distributed...... across a spawning season were analysed. Our results show that multiple males contributed sperm to most spawnings but that paternity frequencies were highly skewed among males, with larger males on average siring higher proportions of offspring. It was further indicated that male reproductive success...

Reduced costs of reproduction in females mediate a shift from a male-biased to a female-biased lifespan in humans

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Bolund, Elisabeth; Lummaa, Virpi; Smith, Ken R.; Hanson, Heidi A.; Maklakov, Alexei A.

2016-01-01

The causes underlying sex differences in lifespan are strongly debated. While females commonly outlive males in humans, this is generally less pronounced in societies before the demographic transition to low mortality and fertility rates. Life-history theory suggests that reduced reproduction should benefit female lifespan when females pay higher costs of reproduction than males. Using unique longitudinal demographic records on 140,600 reproducing individuals from the Utah Population Database, we demonstrate a shift from male-biased to female-biased adult lifespans in individuals born before versus during the demographic transition. Only women paid a cost of reproduction in terms of shortened post-reproductive lifespan at high parities. Therefore, as fertility decreased over time, female lifespan increased, while male lifespan remained largely stable, supporting the theory that differential costs of reproduction in the two sexes result in the shifting patterns of sex differences in lifespan across human populations. Further, our results have important implications for demographic forecasts in human populations and advance our understanding of lifespan evolution. PMID:27087670

Divergent hypoxia tolerance in adult males and females of the plainfin midshipman (Porichthys notatus).

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LeMoine, Christophe M R; Bucking, Carol; Craig, Paul M; Walsh, Patrick J

2014-01-01

In the summer, the plainfin midshipman (Poricththys notatus) migrates to reproduce in the nearshore environment, where oxygen levels are influenced by the tidal cycles. Parental males establish nests under rocks in the intertidal zone, where they reside until the eggs they guard are fully developed. In contrast, females and sneaker males leave the nests shortly after spawning. We examined the physiological resistance and metabolic response of parental male and female adult midshipman to hypoxia to test whether they exhibited sex-specific differences reflecting their reproductive strategies. Further, we assessed whether metabolic enzymes and metabolites were differentially enriched in tissues of parental males and females to explain the differences observed in their hypoxia tolerance. While parental males and females exhibited similar depression of their oxygen consumption in response to graded hypoxia, parental males could withstand significantly longer exposures to severe hypoxic stress. At the biochemical level, parental males showed higher hepatic glycogen reserves and higher glycolytic enzyme capacities in gills and skeletal muscles than females. Although some of these enzymatic variations could be explained by differences in body size, we also observed a significant effect of sex on some of these factors. These results suggest that parental male midshipman may benefit from sexual dimorphism at the whole-organismal (larger body size) and biochemical (enzyme activities) levels, conferring on them a higher glycolytic potential to sustain the extensive hypoxia bouts they experience in nature.

46,XX male disorder of sexual development:a case report.

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Anık, Ahmet; Çatlı, Gönül; Abacı, Ayhan; Böber, Ece

2013-01-01

The main factor influencing sex determination of an embryo is the sex-determining region Y (SRY), a master regulatory gene located on the Y chromosome. The presence of SRY causes the bipotential gonad to differentiate into a testis. However, some individuals carry a Y chromosome but are phenotypically female (46,XY females) or have a female karyotype but are phenotypically male (46,XX males). 46, XX male is rare (1:20 000 in newborn males), and SRY positivity is responsible for this condition in approximately 90% of these subjects. External genitalia of 46,XX SRY-positive males appear as normal male external genitalia, and such cases are diagnosed when they present with small testes and/or infertility after puberty. Herein, we report an adolescent who presented with low testicular volume and who was diagnosed as a 46,XX male. SRY positivity was demonstrated in the patient by fluorescence in situ hybridization method.

Males and females gain differentially from sociality in a promiscuous fruit bat Cynopterus sphinx.

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Kritika M Garg

Full Text Available Sociality emerges when the benefits of group living outweigh its costs. While both males and females are capable of strong social ties, the evolutionary drivers for sociality and the benefits accrued maybe different for each sex. In this study, we investigate the differential reproductive success benefits of group membership that males and females might obtain in the promiscuous fruit bat Cynopterus sphinx. Individuals of this species live in flexible social groups called colonies. These colonies are labile and there is high turnover of individuals. However, colony males sire more offspring within the colony suggesting that being part of a colony may result in reproductive benefits for males. This also raises the possibility that long-term loyalty towards the colony may confer additional advantage in terms of higher reproductive success. We used ten seasons of genetic parentage data to estimate reproductive success and relatedness of individuals in the colony. We used recapture data to identify long and short-term residents in the colony as well as to obtain rates of recapture for males and females. Our results reveal that males have a significantly higher chance of becoming long-term residents (than females, and these long-term resident males gain twice the reproductive success compared to short-term resident males. We also observed that long-term resident females are related to each other and also achieve higher reproductive success than short-term resident females. In contrast, long-term resident males do not differ from short-term resident males in their levels of relatedness. Our results re-iterate the benefits of sociality even in species that are promiscuous and socially labile and possible benefits of maintaining a colony.

Males and females gain differentially from sociality in a promiscuous fruit bat Cynopterus sphinx.

Science.gov (United States)

Garg, Kritika M; Chattopadhyay, Balaji; Swami Doss, D P; Kumar, A K Vinoth; Kandula, Sripathi; Ramakrishnan, Uma

2015-01-01

Sociality emerges when the benefits of group living outweigh its costs. While both males and females are capable of strong social ties, the evolutionary drivers for sociality and the benefits accrued maybe different for each sex. In this study, we investigate the differential reproductive success benefits of group membership that males and females might obtain in the promiscuous fruit bat Cynopterus sphinx. Individuals of this species live in flexible social groups called colonies. These colonies are labile and there is high turnover of individuals. However, colony males sire more offspring within the colony suggesting that being part of a colony may result in reproductive benefits for males. This also raises the possibility that long-term loyalty towards the colony may confer additional advantage in terms of higher reproductive success. We used ten seasons of genetic parentage data to estimate reproductive success and relatedness of individuals in the colony. We used recapture data to identify long and short-term residents in the colony as well as to obtain rates of recapture for males and females. Our results reveal that males have a significantly higher chance of becoming long-term residents (than females), and these long-term resident males gain twice the reproductive success compared to short-term resident males. We also observed that long-term resident females are related to each other and also achieve higher reproductive success than short-term resident females. In contrast, long-term resident males do not differ from short-term resident males in their levels of relatedness. Our results re-iterate the benefits of sociality even in species that are promiscuous and socially labile and possible benefits of maintaining a colony.

Oxytocin mediates copulation-induced hypoalgesia of male rats.

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Futagami, Hiroko; Sakuma, Yasuo; Kondo, Yasuhiko

2016-04-08

Copulatory behavior has been reported to raise the pain threshold in male rats. In this study, we examined the effect of copulatory behavior with or without ejaculation on pain threshold measured by electrical shock via an electrode attached to the tail. It was demonstrated that ejaculation is not necessary to raise the pain threshold in male rats. In addition, we examined whether oxytocin, a hypothalamic neuropeptide, was involved in copulation-induced hypoalgesia. Sexually experienced males were subjected to stereotaxic implantation of a guide cannula targeting the lateral ventricle. After the recovery period, half of the males were intracerebroventricularly treated with an oxytocin antagonist (OTA, 100ng d(CH2)51,Tyr(Me)2,Thr4, Orn8,Tyr-NH29]-vasotocin/1μL saline) and the remaining half were administered saline without anesthesia. Fifteen minutes later, half of each group were given sexual behavior with receptive females. We found no effect of OTA on sexual activity. Immediately after ejaculation, pain threshold was measured. While raised pain threshold was observed after sexual behavior in saline-treated males, no change in pain threshold was found in OTA-treated males even after copulation. The results suggest that central oxytocin mediates copulation-induced hypoalgesia in male rats. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Male-mediated developmental toxicity

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Diana Anderson

2014-02-01

Full Text Available Male-mediated developmental toxicity has been of concern for many years. The public became aware of male-mediated developmental toxicity in the early 1990s when it was reported that men working at Sellafield might be causing leukemia in their children. Human and animal studies have contributed to our current understanding of male-mediated effects. Animal studies in the 1980s and 1990s suggested that genetic damage after radiation and chemical exposure might be transmitted to offspring. With the increasing understanding that there is histone retention and modification, protamine incorporation into the chromatin and DNA methylation in mature sperm and that spermatozoal RNA transcripts can play important roles in the epigenetic state of sperm, heritable studies began to be viewed differently. Recent reports using molecular approaches have demonstrated that DNA damage can be transmitted to babies from smoking fathers, and expanded simple tandem repeats minisatellite mutations were found in the germline of fathers who were exposed to radiation from the Chernobyl nuclear power plant disaster. In epidemiological studies, it is possible to clarify whether damage is transmitted to the sons after exposure of the fathers. Paternally transmitted damage to the offspring is now recognized as a complex issue with genetic as well as epigenetic components.

Reproductive effects of lipid soluble components of Syzygium aromaticum flower bud in male mice

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Raghav Kumar Mishra

2013-01-01

Full Text Available Background: The flower buds of Syzygium aromaticum (clove have been used in indigenous medicines for the treatment of male sexual disorders in Indian subcontinent. Objective: To evaluate the effect of Syzygium aromaticum flower bud on male reproduction, using Parkes (P strain mice as animal model. Materials and Methods: Mice were orally administered lipid soluble components of Syzygium aromaticum flower bud in doses of 15, 30, and 60 mg/kg body weight for 35 days, and several male reproductive endpoints were evaluated. Results: Treatment with lower dose (15 mg of Syzygium increased the motility of sperm and stimulated the secretory activities of epididymis and seminal vesicle, while higher doses (30 and 60 mg had adverse effects on sperm dynamics of cauda epididymidis and on the secretory activities of epididymis and seminal vesicle. Libido was not affected in treated males; however, a significant decrease in litter in females sired by males treated with higher doses of Syzygium was recorded. Conclusion: Treatment with Syzygium aromaticum flower bud causes dose-dependent biphasic effect on male reproductive indices in P mice; lower dose of Syzygium appears stimulatory, while the higher doses have adverse effect on male reproduction. The results suggest that the lower dose of Syzygium may have androgenic effect, but further studies are needed to support this contention.

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

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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.

Promoting Financial Literacy and Latino Males' Success at Community Colleges

Science.gov (United States)

Salinas, Cristobal, Jr.; Hidrowoh, Jacob R.

2018-01-01

Latino males across the country enroll in community colleges with the purpose of obtaining an educational degree, which could lead to accomplishing professional and personal aspirations. Even if Latino male students enroll in post-secondary education, they continue to be disenfranchised, vanished, and often rejected through the higher education…

Association of anthropometric qualities with vertical jump performance in elite male volleyball players.

Science.gov (United States)

Aouadi, R; Jlid, M C; Khalifa, R; Hermassi, S; Chelly, M S; Van Den Tillaar, R; Gabbett, T

2012-02-01

The objective of this study was to examine the association between physical and anthropometric profiles and vertical jump performance in elite volleyball players. Thirty-three elite male volleyball players (21±1 y, 76.9±5.2 kg, 186.5±5 cm) were studied. Several anthropometric measurements (body mass, stature, body mass index, lower limb length and sitting height) together with jumping height anaerobic power of counter movement jump with arm swing (CMJarm) were obtained from all subjects. Forward stepwise multiple linear regression analysis was performed to determine if any of the anthropometric parameters were predictive of CMJarm. Anaerobic power was significantly higher (P≤0.05) in the tallest players relative to their shorter counterparts. A significant relationship was observed between CMJarm and lower limb length (r2=0.69; P0.05) predictors of CMJarm performance. This study demonstrates that lower limb length is correlated with CMJarm in elite male volleyball players. The players with longer lower limbs have the better vertical jump performances and their anaerobic power is higher. These results could be of importance for trained athletes in sports relying on jumping performance, such as basketball, handball or volleyball. Thus, the measurement of anthropometric characteristics, such as stature and lower limb length may assist coaches in the early phases of talent identification in volleyball.

Robotic crabs reveal that female fiddler crabs are sensitive to changes in male display rate.

Science.gov (United States)

Mowles, Sophie L; Jennions, Michael D; Backwell, Patricia R Y

2018-01-01

Males often produce dynamic, repetitive courtship displays that can be demanding to perform and might advertise male quality to females. A key feature of demanding displays is that they can change in intensity: escalating as a male increases his signalling effort, but de-escalating as a signaller becomes fatigued. Here, we investigated whether female fiddler crabs, Uca mjoebergi , are sensitive to changes in male courtship wave rate. We performed playback experiments using robotic male crabs that had the same mean wave rate, but either escalated, de-escalated or remained constant. Females demonstrated a strong preference for escalating robots, but showed mixed responses to robots that de-escalated ('fast' to 'slow') compared to those that waved at a constant 'medium' rate. These findings demonstrate that females can discern changes in male display rate, and prefer males that escalate, but that females are also sensitive to past display rates indicative of prior vigour. © 2018 The Authors.

Androgens and the ageing male

DEFF Research Database (Denmark)

Juul, Anders; Skakkebaek, Niels E

2002-01-01

Hypogonadal men share a variety of signs and symptoms such as decreased muscle mass, osteopoenia, increased fat mass, fatigue, decreased libido and cognitive dysfunctions. Controlled trials have demonstrated favourable effects of androgen substitution therapy on these signs and symptoms in men...... 'andropause' has been suggested. However, testosterone levels show no or only modest variation with age in men; with large prospective studies suggesting a maximal decline of total testosterone of 1.6% per year. Thus, in contrast to the sudden arrest of gonadal activity in females around menopause, men do...... not have an andropause. As large placebo-controlled studies of androgen treatment in elderly males are lacking, proper risk assessment of adverse effects such as prostate cancer following testosterone treatment in elderly males is completely lacking. In the future, testosterone therapy may prove beneficial...

Higher P-Wave Dispersion in Migraine Patients with Higher Number of Attacks

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A. Koçer

2012-01-01

Full Text Available Objective and Aim. An imbalance of the sympathetic system may explain many of the clinical manifestations of the migraine. We aimed to evaluate P-waves as a reveal of sympathetic system function in migraine patients and healthy controls. Materials and Methods. Thirty-five episodic type of migraine patients (complained of migraine during 5 years or more, BMI < 30 kg/m2 and 30 controls were included in our study. We measured P-wave durations (minimum, maximum, and dispersion from 12-lead ECG recording during pain-free periods. ECGs were transferred to a personal computer via a scanner and then used for magnification of x400 by Adobe Photoshop software. Results. P-wave durations were found to be similar between migraine patients and controls. Although P WD (P-wave dispersion was similar, the mean value was higher in migraine subjects. P WD was positively correlated with P max (P<0.01. Attacks number per month and male gender were the factors related to the P WD (P<0.01. Conclusions. Many previous studies suggested that increased sympathetic activity may cause an increase in P WD. We found that P WD of migraine patients was higher than controls, and P WD was related to attacks number per month and male gender. Further studies are needed to explain the chronic effects of migraine.

Neonatal Overnutrition Increases Testicular Size and Expression of Luteinizing Hormone β-Subunit in Peripubertal Male Rats

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Pilar Argente-Arizón

2018-04-01

Full Text Available Proper nutrition is important for growth and development. Maturation of the reproductive axis and the timing of pubertal onset can be delayed when insufficient nutrition is available, or possibly advanced with nutritional abundance. The childhood obesity epidemic has been linked to a secular trend in advanced puberty in some populations. The increase in circulating leptin that occurs in association with obesity has been suggested to act as a signal that an adequate nutritional status exists for puberty to occur, allowing activation of central mechanisms. However, obesity-associated hyperleptinemia is linked to decreased leptin sensitivity, at least in adults. Here, we analyzed whether neonatal overnutrition modifies the response to an increase in leptin in peripubertal male rats, as previously demonstrated in females. Wistar rats were raised in litters of 4 (neonatal overnutrition or 12 pups (controls per dam. Leptin was administered sc (3 µg/g body weight at postnatal day 35 and the rats killed 45 min or 2 h later. Postnatal overfeeding resulted in increased body weight and circulating leptin levels; however, we found no overweight-related changes in the mRNA levels of neuropeptides involved in metabolism or reproduction. In contrast, pituitary expression of luteinizing hormone (LH beta-subunit was increased in overweight rats, as was testicular weight. There were no basal differences between L4 and L12 males or in their response to leptin administration in pSTAT3 levels in the hypothalamus at either 45 min or 2 h. In contrast, pJAK2 was found to be higher at 45 min in L4 compared to L12 males regardless of leptin treatment, while at 2 h it was higher in L4 leptin-treated males compared to L12 leptin-treated males, as well as L4 vehicle-treated rats. There were no changes in response to leptin administration in the expression of the neuropeptides analyzed. However, serum LH levels rose only in L4 males in response to leptin, but

Neonatal Overnutrition Increases Testicular Size and Expression of Luteinizing Hormone β-Subunit in Peripubertal Male Rats

Science.gov (United States)

Argente-Arizón, Pilar; Castro-González, David; Díaz, Francisca; Fernández-Gómez, María J.; Sánchez-Garrido, Miguel A.; Tena-Sempere, Manuel; Argente, Jesús; Chowen, Julie A.

2018-01-01

Proper nutrition is important for growth and development. Maturation of the reproductive axis and the timing of pubertal onset can be delayed when insufficient nutrition is available, or possibly advanced with nutritional abundance. The childhood obesity epidemic has been linked to a secular trend in advanced puberty in some populations. The increase in circulating leptin that occurs in association with obesity has been suggested to act as a signal that an adequate nutritional status exists for puberty to occur, allowing activation of central mechanisms. However, obesity-associated hyperleptinemia is linked to decreased leptin sensitivity, at least in adults. Here, we analyzed whether neonatal overnutrition modifies the response to an increase in leptin in peripubertal male rats, as previously demonstrated in females. Wistar rats were raised in litters of 4 (neonatal overnutrition) or 12 pups (controls) per dam. Leptin was administered sc (3 µg/g body weight) at postnatal day 35 and the rats killed 45 min or 2 h later. Postnatal overfeeding resulted in increased body weight and circulating leptin levels; however, we found no overweight-related changes in the mRNA levels of neuropeptides involved in metabolism or reproduction. In contrast, pituitary expression of luteinizing hormone (LH) beta-subunit was increased in overweight rats, as was testicular weight. There were no basal differences between L4 and L12 males or in their response to leptin administration in pSTAT3 levels in the hypothalamus at either 45 min or 2 h. In contrast, pJAK2 was found to be higher at 45 min in L4 compared to L12 males regardless of leptin treatment, while at 2 h it was higher in L4 leptin-treated males compared to L12 leptin-treated males, as well as L4 vehicle-treated rats. There were no changes in response to leptin administration in the expression of the neuropeptides analyzed. However, serum LH levels rose only in L4 males in response to leptin, but with no change

Life history in male mandrills (Mandrillus sphinx): physical development, dominance rank, and group association.

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Setchell, Joanna M; Wickings, E Jean; Knapp, Leslie A

2006-12-01

We assess life history from birth to death in male mandrills (Mandrillus sphinx) living in a semifree-ranging colony in Gabon, using data collected for 82 males that attained at least the age of puberty, including 33 that reached adulthood and 25 that died, yielding data for their entire lifespan. We describe patterns of mortality and injuries, dominance rank, group association, growth and stature, and secondary sexual character expression across the male lifespan. We examine relationships among these variables and investigate potential influences on male life history, including differences in the social environment (maternal rank and group demography) and early development, with the aim of identifying characteristics of successful males. Sons of higher-ranking females were more likely to survive to adulthood than sons of low-ranking females. Adolescent males varied consistently in the rate at which they developed, and this variation was related to a male's own dominance rank. Males with fewer peers and sons of higher-ranking and heavier mothers also matured faster. However, maternal variables were not significantly related to dominance rank during adolescence, the age at which males attained adult dominance rank, or whether a male became alpha male. Among adult males, behavior and morphological development were related to a male's own dominance rank, and sons of high-ranking females were larger than sons of low-ranking females. Alpha males were always the most social, and the most brightly colored males, but were not necessarily the largest males present. Finally, alpha male tenure was related to group demography, with larger numbers of rival adult males and maturing adolescent males reducing the time a male spent as alpha male. Tenure did not appear to be related to characteristics of the alpha male himself. 2006 Wiley-Liss, Inc.

Benign papilloma of the male breast following chronic phenothiazine therapy.

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Sara, A S; Gottfried, M R

1987-05-01

Benign intraductal papilloma is a rare lesion in the male breast. The authors report the occurrence of an intraductal papilloma in a male with more than a ten-year history of phenothiazine therapy (Mellaril and Prolixin). Phenothiazines have been demonstrated to cause elevated serum prolactin levels. The literature regarding the relationship between prolactin and mammary tumors in rodents and in humans remains controversial. The occurrence of this rare male breast tumor in the setting of chronic phenothiazine therapy raises further questions as to the role of prolactin in the development of mammary tumors.

Africa takes a more male-friendly approach to family planning.

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Omuodo, D O

1996-12-01

It has been demonstrated that men are more likely to support family planning (FP) and to use a method themselves if services and educational programs are targeted to them. Because men fear that contraception reduces their control over their wives' sexuality, male-friendly approaches can enhance gender equality in reproductive health decisions. In Togo, the media is being used to encourage positive attitudes towards FP in specific male groups. In Ghana, FP services targeted to men have resulted in increased male involvement. In Swaziland, male audiences are targeted with FP education. In Sierra Leone, men have met in groups to learn about how to prevent sexually transmitted diseases and about the benefits of FP, and in Kenya, three male-only clinics exist to provide FP services to men.

Variation in male reproductive longevity across traditional societies.

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Lucio Vinicius

Full Text Available Most accounts of human life history propose that women have short reproductive spans relative to their adult lifespans, while men not only remain fertile but carry on reproducing until late life. Here we argue that studies have overlooked evidence for variation in male reproductive ageing across human populations. We apply a Bayesian approach to census data from Agta hunter-gatherers and Gambian farmers to show that long post-reproductive lifespans characterise not only women but also males in some traditional human populations. We calculate three indices of reproductive ageing in men (oldest age at reproduction, male late-life reproduction, and post-reproductive representation and identify a continuum of male reproductive longevity across eight traditional societies ranging from !Kung, Hadza and Agta hunter-gatherers exhibiting low levels of polygyny, early age at last reproduction and long post-reproductive lifespans, to male Gambian agriculturalists and Turkana pastoralists showing higher levels of polygyny, late-life reproduction and shorter post-reproductive lifespans. We conclude that the uniquely human detachment between rates of somatic senescence and reproductive decline, and the existence of post-reproductive lifespans, are features of both male and female life histories, and therefore not exclusive consequences of menopause.

Males in Enabling: Painting a portrait through narrative

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Frank Armstrong

2018-02-01

Full Text Available The number of males entering higher education via an enabling pathway is slowly increasing; yet, males still battle with the anti-intellectual attitude that is prevalent in regional areas of Australia. Previous research undertaken by the authors began exploring the factors that inhibited or enhanced the male experience within an enabling course. This paper expands upon this research with a deeper focus on the male experience through personalised accounts derived from individual interviews. Using qualitative methodology and narrative inquiry, the findings provide a deeper understanding of the issues that males of different ages face when creating a new identity as a university student. This paper shares insights into what motivated the male students to enter university via an enabling pathway; the actual personal experiences both positive and negative during this time; and the effect that this commitment to study had on them personally and the people around them. The lens of transformative theory underpins this research through exploring frames of reference that align with the students’ experiences. Portraiture prose shares the individual stories which are analysed and the key findings extrapolated.

Countries with women inequalities have higher stroke mortality.

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Kim, Young Dae; Jung, Yo Han; Caso, Valeria; Bushnell, Cheryl D; Saposnik, Gustavo

2017-10-01

Background Stroke outcomes can differ by women's legal or socioeconomic status. Aim We investigated whether differences in women's rights or gender inequalities were associated with stroke mortality at the country-level. Methods We used age-standardized stroke mortality data from 2008 obtained from the World Health Organization. We compared female-to-male stroke mortality ratio and stroke mortality rates in women and men between countries according to 50 indices of women's rights from Women, Business and the Law 2016 and Gender Inequality Index from the Human Development Report by the United Nations Development Programme. We also compared stroke mortality rate and income at the country-level. Results In our study, 176 countries with data available on stroke mortality rate in 2008 and indices of women's rights were included. There were 46 (26.1%) countries where stroke mortality in women was higher than stroke mortality in men. Among them, 29 (63%) countries were located in Sub-Saharan African region. After adjusting by country income level, higher female-to-male stroke mortality ratio was associated with 14 indices of women's rights, including differences in getting a job or opening a bank account, existence of domestic violence legislation, and inequalities in ownership right to property. Moreover, there was a higher female-to-male stroke mortality ratio among countries with higher Gender Inequality Index (r = 0.397, p Gender Inequality Index was more likely to be associated with stroke mortality rate in women than that in men (p gender inequality status is associated with women's stroke outcomes.

INDUCTION OF GONADAL MATURATION OF POND CULTURED MALE TIGER SHRIMP, Penaeus monodon WITH DIFFERENT DOSAGES OF GONADOTROPIN RELEASING HORMONE ANALOGUE AGAINST EYE STALK ABLATION

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Asda Laining

2016-12-01

Full Text Available Very low naturally mating rate of pond-reared tiger shrimp broodstock is probably due to the slow maturation of the male stock. The aim of this study was to evaluate the salmon gonadotrophin releasing hormone analoque (sGnRHa in stimulating the gonadal maturation of male stock of pond-reared tiger shrimp. The treatments were three dosages of sGnRHa at 0.1 (OV-1, 0.2 (OV-2, and 0.3 (OV-3 mL/kg of shrimp weight and control was eye stalk ablation (AB. The sGnRHa was administered via injection three times with one week interval. Male stocks with average initial body weight of 82.1 g were randomly distributed into four of 10 m3 concrete tanks, 26 males for each tank. Variables observed were performances of spermatophores and profiles of amino acid and fatty acid of muscle of the male stocks. After induction, number of male maturing indicated by spermatophores releasing from terminal ampullas was higher in shrimp induced with OV-1 (80.8% compared to control which was only 46.1%. Furthermore, shrimp treated OV-2 had the highest spermatophore weight of 0.16 g compared to control (0.11 g and other two groups. Amino acid profiles improved as the dose of sGnRHa increased up to 0.2 mL/kg from 61.23% for ablated male becoming 71.27% for OV-2. Total fatty acid also tended to improve by increasing the dose of hormone injection, however, the ablated male had higher total fatty acid content than that of OV-1. The present finding demonstrated that the dose of sGnRHa to stimulate the gonadal maturation of pond-reared male tiger shrimp could be applied at range between 0.1-0.2 mL/kg of shrimp weight.

Effect of Age and Caponization on Blood Parameters and Bone Development of Male Native Chickens in Taiwan

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Cheng-Yung Lin

2012-07-01

Full Text Available An experiment was carried out to determine the effect of age and caponization on the development blood and bone characteristics development in male country chickens in Taiwan. A total of two hundred 8-wk-old LRI native chicken cockerels, Taishi meat No.13 from LRI-COA, were used as experimental animals. Cockerels were surgically caponized at 8 wks of age. Twelve birds in each group were bled and dressed from 8 wks to 35 wks of age at 1 to 5 wk intervals. The results indicated that the plasma testosterone concentration was significantly (p<0.05 lower in capons after 12 wks of age (caponized treatment after 4 wks than that of the intact males. The relative tibia weight, bone breaking strength, cortical thickness, bone ash, bone calcium, bone phosphorus and bone magnesium contents were significantly (p<0.05 higher in intact males, while capons had higher (p<0.05 plasma ionized calcium, inorganic phosphorus and alkaline phosphatase concentration. The plasma testosterone concentration, relative tibia weight, tibia length, breaking strength, cortical thickness, bone ash, calcium, and phosphorus contents of intact males chickens increased significantly (p<0.05 with the advance of age. In addition, the relative tibia weight of capons peaked at 18 wks of age, and declined at 35 wks of age. The bone ash, calcium and phosphorus content increased most after 14 wks of age in male native chickens in Taiwan. Also, tibia length and cortical thickness peaked at 22 wks of age. However, the peak of bone strength was found at 26 wks of age. These findings support the assertion that androgens can directly influence bone composition fluxes in male chickens. Caponization caused a significant increase in bone loss at 4 wks post treatment, which reflected bone cell damage, and demonstrated reductions in the relative tibia weight, breaking strength, cortical thickness, bone ash, calcium, phosphorus and magnesium contents, and increases in plasma ionized calcium

Characterization of untreated and treated male and female date palm leaves

International Nuclear Information System (INIS)

AlMaadeed, M.A.; Kahraman, Ramazan; Noorunnisa Khanam, P.; Al-Maadeed, Somaya

2013-01-01

Highlights: ► Sheshi female and male date palm leaves were treated with NaOH concentrations. ► Male leaves have lower mechanical properties and improved when treated by NaOH 2%. ► Female leaves have higher thermal stability. ► There are different properties for different types of date leaves. ► Leaves can be used as reinforcements for thermoplastic materials. -- Abstract: This paper describes the characterization of male and female date palm leaves from two different cultivars, Sheshi female and unknown male leaves. Characterization was done for both untreated and NaOH treated date palm leaves by infrared spectroscopy, thermogravimetric analysis and scanning electron microscopic techniques. To our knowledge, the difference in specious reaction to the treatment type of date palm fiber has not been investigated earlier. These leaves were treated with different concentrations of NaOH, 0.5%, 1%, 2% and 5% (w/w). The results from this investigation indicate that female leaves have better tensile properties which deteriorate with the increase of the alkali. The male leaves have lower tensile properties than female leaves and their mechanical properties are improved slightly by NaOH treatment. Female leaves have more pores than male leaves, this was proved and calculated by image analysis. Untreated female leaves have higher thermal stability (353 °C) than male leaves (343 °C). Both can be used as reinforcements in thermoplastic matrix materials whose processing temperatures are below 300 °C.

Sexual selection by male choice in monogamous and polygynous human populations.

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Ihara, Y; Aoki, K

1999-02-01

The theoretical possibility of coevolution of a viability-reducing female physical trait and a male mating preference for that trait by Fisherian sexual selection in monogamous and polygynous populations is demonstrated using two-locus haploid models. It is assumed that there is dichotomous variation in male resources, resource-rich males have a wider choice among females than resource-poor males, and a female has greater reproductive success when mated with a resource-rich male than a resource-poor one. Under these assumptions, we find that sexual selection operates effectively when female reproductive success is strongly dependent on male resource, the proportion of females that mate with resource-rich males is neither small nor large, the degree of polygyny is low, and resources are inherited from father to son. We suggest that some human female physical traits may have evolved by sexual selection through male choice. The evolution of skin color by sexual selection is discussed as an example. Copyright 1999 Academic Press.

Neuromuscular and lower limb biomechanical differences exist between male and female elite adolescent soccer players during an unanticipated side-cut maneuver.

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Landry, Scott C; McKean, Kelly A; Hubley-Kozey, Cheryl L; Stanish, William D; Deluzio, Kevin J

2007-11-01

Female athletes are 2 to 8 times more likely than male athletes to injure the anterior cruciate ligament during a non-contact athletic maneuver. Identifying anterior cruciate ligament injury risk factors in female athletes may help with the development of preventive training programs aimed at reducing injury rates. Differences between genders in lower limb kinematics, kinetics, and neuromuscular patterns will be identified in an adolescent soccer population during an unanticipated side-cut maneuver. Controlled laboratory study. Forty-two elite adolescent soccer players (21 male and 21 female) performed an unanticipated side-cut maneuver, with the 3-dimensional kinematic, kinetic, and electromyographic lower limb data being analyzed using principal component analysis. The female athletes had higher gastrocnemius activity, normalized to maximal voluntary isometric contractions, and a mediolateral gastrocnemius activation imbalance that was not present in the male athletes during early stance to midstance of the side-cut. Female athletes demonstrated greater rectus femoris muscle activity throughout stance, and the only hamstring difference identified was a mediolateral activation imbalance in male athletes only. Female athletes performed the side-cut with less hip flexion and more hip external rotation and also generated a smaller hip flexion moment compared with the male athletes. This is the first study to identify gender-related differences in gastrocnemius muscle activity during an unanticipated cutting maneuver. The increased and imbalanced gastrocnemius muscle activity, combined with increased rectus femoris muscle activity and reduced hip flexion angles and moments in female subjects, may all have important contributing roles in the higher noncontact ACL injury rates observed in female athletes.

Female scent signals enhance the resistance of male mice to influenza.

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Ekaterina A Litvinova

Full Text Available BACKGROUND: The scent from receptive female mice functions as a signal, which stimulates male mice to search for potential mating partners. This searching behavior is coupled with infection risk due to sniffing both scent marks as well as nasal and anogenital areas of females, which harbor bacteria and viruses. Consideration of host evolution under unavoidable parasitic pressures, including helminthes, bacteria, viruses, etc., predicts adaptations that help protect hosts against the parasites associated with mating. METHODS AND FINDINGS: We propose that the perception of female signals by BALB/c male mice leads to adaptive redistribution of the immune defense directed to protection against respiratory infection risks. Our results demonstrate migration of macrophages and neutrophils to the upper airways upon exposure to female odor stimuli, which results in an increased resistance of the males to experimental influenza virus infection. This moderate leukocyte intervention had no negative effect on the aerobic performance in male mice. CONCLUSIONS: Our data provide the first demonstration of the adaptive immunological response to female odor stimuli through induction of nonspecific immune responses in the upper respiratory tract.

Individual recognition based on communication behaviour of male fowl.

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Smith, Carolynn L; Taubert, Jessica; Weldon, Kimberly; Evans, Christopher S

2016-04-01

Correctly directing social behaviour towards a specific individual requires an ability to discriminate between conspecifics. The mechanisms of individual recognition include phenotype matching and familiarity-based recognition. Communication-based recognition is a subset of familiarity-based recognition wherein the classification is based on behavioural or distinctive signalling properties. Male fowl (Gallus gallus) produce a visual display (tidbitting) upon finding food in the presence of a female. Females typically approach displaying males. However, males may tidbit without food. We used the distinctiveness of the visual display and the unreliability of some males to test for communication-based recognition in female fowl. We manipulated the prior experience of the hens with the males to create two classes of males: S(+) wherein the tidbitting signal was paired with a food reward to the female, and S (-) wherein the tidbitting signal occurred without food reward. We then conducted a sequential discrimination test with hens using a live video feed of a familiar male. The results of the discrimination tests revealed that hens discriminated between categories of males based on their signalling behaviour. These results suggest that fowl possess a communication-based recognition system. This is the first demonstration of live-to-video transfer of recognition in any species of bird. Copyright © 2016 Elsevier B.V. All rights reserved.

Bone Composition in Male and Female Göttingen Minipigs Fed Variously Restrictedly and near ad Libitum

DEFF Research Database (Denmark)

Bollen, P. J. A.; Lemmens, A. G.; Beynen, A. C.

2006-01-01

diet 2 was a high fat, low fibre diet. A higher level of feed intake led to a significant increase in the following parameters: body weight development, bone size (length and width of rib and femur), bone volume (rib), bone (rib) dry matter and ash content (mg), as well as bone density (femur...... development, bone volume, and dry matter and ash content of the rib (mg) as compared to males. Also bone mineral concentrations in the femur, expressed as calcium, phosphorus and magnesium in mg/cm3, were significantly higher in females as compared to males, as was the Ca:Pi ratio. Bone density measurements...... of the femur’s proximal and distal segment, and total femur bone density (g/cm2) were significantly higher in females as compared to males. Feed conversion in females was significantly lower than in males. This study illustrates that female and male minipigs show distinct differences in body and bone...

Male coercion and convenience polyandry in a calopterygid damselfly

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A. Cordero

2002-08-01

Full Text Available Copulation in odonates requires female cooperation because females must raise their abdomen to allow intromission. Nevertheless in Calopteryx haemorrhoidalis haemorrhoidalis (Odonata males commonly grasp ovipositing females and apparently force copulations. This has been interpreted as a consequence of extreme population density and male-male competition. We studied this behavior at two sites on a river that had different densities over three years. As predicted, at high densities most matings were forced (i.e. not preceded by courtship, but at low density most were preceded by courtship. Courtship matings were shorter at high density, but density did not affect the duration of forced matings. Females cooperated in forced matings even if they had very few mature eggs. Furthermore, females mated more times if they experienced higher male harassment during oviposition, and at low density second and subsequent matings were more likely to be forced. We interpret these results to mean that females engage in "convenience polyandry", because they gain more by accepting copulation than by resisting males. The results also suggest that females might trade copulations for male protection, because under extreme population density harassment by males is so intense that they can impede oviposition.

Social cognition, the male brain and the autism spectrum.

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Jeremy Hall

Full Text Available Behavioral studies have shown that, at a population level, women perform better on tests of social cognition and empathy than men. Furthermore Autism Spectrum Disorders (ASDs, which are characterized by impairments in social functioning and empathy, occur more commonly in males than females. These findings have led to the hypothesis that differences in the functioning of the social brain between males and females contribute to the greater vulnerability of males to ASD and the suggestion that ASD may represent an extreme form of the male brain. Here we sought to investigate this hypothesis by determining: (i whether males and females differ in social brain function, and (ii whether any sex differences in social brain function are exaggerated in individuals with ASD. Using fMRI we show that males and females differ markedly in social brain function when making social decisions from faces (compared to simple sex judgements especially when making decisions of an affective nature, with the greatest sex differences in social brain activation being in the inferior frontal cortex (IFC. We also demonstrate that this difference is exaggerated in individuals with ASD, who show an extreme male pattern of IFC function. These results show that males and females differ significantly in social brain function and support the view that sex differences in the social brain contribute to the greater vulnerability of males to ASDs.

Subcutaneous blood flow in early male pattern baldness

International Nuclear Information System (INIS)

Klemp, P.; Peters, K.; Hansted, B.

1989-01-01

The subcutaneous blood flow (SBF) was measured by the 133 Xe washout method in the scalp of 14 patients with early male pattern baldness. Control experiments were performed in 14 normal haired men matched for age. The SBF in the scalp of the normal individuals was about 10 times higher than previously reported SBF values in other anatomical regions. In patients with early male pattern baldness, SBF was 2.6 times lower than the values found in the normal individuals (13.7 +/- 9.6 vs 35.7 +/- 10.5 ml/100 g/min-1). This difference was statistically significant (p much less than 0.001). A reduced nutritive blood flow to the hair follicles might be a significant event in the pathogenesis of early male pattern baldness

The insults of illicit drug use on male fertility.

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Fronczak, Carolyn M; Kim, Edward D; Barqawi, Al B

2012-01-01

One-third of infertile couples may have a male factor present. Illicit drug use can be an important cause of male factor infertility and includes use of anabolic-androgenic steroids, marijuana, opioid narcotics, cocaine, and methamphetamines. The use of these illicit drugs is common in the United States, with a yearly prevalence rate for any drug consistently higher in males compared with females. We aim to provide a review of recent literature on the prevalence and effects of illicit drug use on male fertility and to aid health professionals when counseling infertile men whose social history suggests illicit drug use. Anabolic-androgenic steroids, marijuana, cocaine, methamphetamines, and opioid narcotics all negatively impact male fertility, and adverse effects have been reported on the hypothalamic-pituitary-testicular axis, sperm function, and testicular structure. The use of illicit drugs is prevalent in our society and likely adversely impacting the fertility of men who abuse drugs.

Systems Toxicology of Male Reproductive Development ...

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Adverse trends in male reproductive health have been reported for increased rates of testicular germ cell tumor, low semen quality, cryptorchidism, and hypospadias. An association with prenatal environmental exposure has been inferred from human and animal studies underlying male reproductive developmental defects. The present study established the links between environmental chemicals, molecular targets, and adverse outcomes using U.S. EPA animal study (ToxRefDB) and high-throughput screening (ToxCast) databases. This systems-based approach revealed a phenotypic hierarchy across 63 chemicals and a pleiotropic in vitro bioactivity profile. Although estrogenic and anti-androgenic activities have been extensively studied in male reproductive developmental toxicity, the present study showed these receptor targets to be only a subset of the potential landscape of molecular targets. A variety of chemical (e.g. phthalates, conazoles, carbamates, and phenol compounds) and bioactivity (e.g. nuclear receptors, vascular remodeling proteins, and cytochrome-P450 reductases) clusters further suggested multiple pathways leading to the adverse outcomes. This points to the need for multi-scale systems models to predict whether the occurrence of one adverse outcome may predict the risk of another. Imbalances in androgen and estrogen signaling have been a general focus in male reproductive toxicology research. While a number of recent studies have demonstrated that both hormonal

Overcoming male factor infertility with intracytoplasmic sperm injection.

Science.gov (United States)

Borges, Edson; Zanetti, Bianca Ferrarini; Braga, Daniela Paes de Almeida Ferreira; Setti, Amanda Souza; Figueira, Rita de Cássia Sávio; Nardi, Aguinaldo César; Iaconelli, Assumpto

2017-08-01

To evaluate the effect of male factor infertility on intracytoplasmic sperm injection (ICSI) outcomes compared with a control group presenting isolated tubal factor. This retrospective study included 743 couples undergoing ICSI as a result of isolated male factor and a control group consisting of 179 couples undergoing ICSI as a result of isolated tubal factor, performed in a private university- -affiliated in vitro fertilization center, between January/2010 and December/2016. Patients were divided into two groups according to maternal age: women ≤35 years old and >35 years old. The effects of infertility causes on laboratorial and clinical ICSI outcomes were evaluated using Student's t-test and (2 test. No differences in controlled ovarian stimulation outcomes were observed between male factor cycles and tubal factor cycles in the two age groups. Implantation (male factor 35.5% vs. tubal factor 32.0%, p=0.340), pregnancy (male factor 46.9% vs. tubal factor 40.9%, p=0.184) and miscarriage (male factor 10.3% vs. tubal factor 10.6%, p=0.572) rates were similar between the infertility groups, irrespective of female age. Considering maternal age, the cancelation rate was higher in older women (>35 years old) undergoing ICSI as a result of male factor infertility (17.4% vs. 8.9%, p=0.013). Our results showed that there is no difference in the outcomes of pregnancy between couples with male or tubal factor infertility, which indicates that ICSI surpasses the worse specific outcomes associated with male factor.

Chromosomal disorders and male infertility

Institute of Scientific and Technical Information of China (English)

Gary L Harton; Helen G Tempest

2012-01-01

infertility in humans is surprisingly common occurring in approximately 15％ of the population wishing to start a family.Despite this,the molecular and genetic factors underlying the cause of infertility remain largely undiscovered.Nevertheless,more and more genetic factors associated with infertility are being identified.This review will focus on our current understanding of the chromosomal basis of male infertility specifically:chromosomal aneuploidy,structural and numerical karyotype abnormalities and Y chromosomal microdeletions.Chromosomal aneuploidy is the leading cause of pregnancy loss and developmental disabilities in humans.Aneuploidy is predominantly maternal in origin,but concerns have been raised regarding the safety of intracytoplasmic sperm injection as infertile men have significantly higher levels of sperm aneuploidy compared to their fertile counterparts.Males with numerical or structural karyotype abnormalities are also at an increased risk of producing aneuploid sperm.Our current understanding of how sperm aneuploidy translates to embryo aneuploidy will be reviewed,as well as the application of preimplantation genetic diagnosis (PGD) in such cases.Clinical recommendations where possible will be made,as well as discussion of the use of emerging array technology in PGD and its potential applications in male infertility.

Endometriosis in the male.

Science.gov (United States)

Martin, J D; Hauck, A E

1985-07-01

An 83-year-old man with an endometrioma of the lower abdominal wall has been reported. This occurred following the administration of 25 mg of TACE for a period of about 10 years for what was thought to be carcinoma of the prostate. A second transurethral resection done by Dr. R. C. Thompson proved to be adenocarcinoma. Subsequent to this he was continued on TACE. A review of the more commonly accepted theories of the development of endometriosis in the female has been presented. It is pointed out that the separation between the male and female urogenital systems occurs in the embryo between the eighth week and the fourth month. There is always a possibility for remnants of the opposite sex to remain in individuals. No such was seen in the case which is herein reported. Normal phenotype male was demonstrated in the chromosomal evaluation. A review of the literature on endometriosis in the male reveals several cases which have occurred; the origin of which is though to be from the prostatic utricle which is a remnant of the uterus existing in the male. After a prolonged course the patient reported was followed until he died in 1979. There was no recurrence of the abdominal wall mass but persistent low grade carcinoma of the prostate remained. The terminal process was related to cardiovascular disease and not carcinoma of the prostate. There was delay in publication of this unusual case. The original plan was to await final confirmation of the exact pathologic nature of this condition; unfortunately this was never done since a postmortem examination was not performed.(ABSTRACT TRUNCATED AT 250 WORDS)

Secondary Conditions Among Males With Duchenne or Becker Muscular Dystrophy.

Science.gov (United States)

Latimer, Rebecca; Street, Natalie; Conway, Kristin Caspers; James, Kathy; Cunniff, Christopher; Oleszek, Joyce; Fox, Deborah; Ciafaloni, Emma; Westfield, Christina; Paramsothy, Pangaja

2017-06-01

Duchenne and Becker muscular dystrophy are X-linked neuromuscular disorders characterized by progressive muscle degeneration. Despite the involvement of multiple systems, secondary conditions among affected males have not been comprehensively described. Two hundred nine caregivers of affected males (aged 3-31 years) identified by the Muscular Dystrophy Surveillance, Tracking, and Research Network completed a mailed survey that included questions about secondary conditions impacting multiple body functions. The 5 most commonly reported conditions in males with Duchenne were cognitive deficits (38.4%), constipation (31.7%), anxiety (29.3%), depression (27.4%), and obesity (19.5%). Higher frequencies of anxiety, depression, and kidney stones were found among nonambulatory males compared to ambulatory males. Attention-deficit hyperactivity disorder (ADHD) was more common in ambulatory than nonambulatory males. These data support clinical care recommendations for monitoring of patients with Duchenne or Becker muscular dystrophy by a multidisciplinary team to prevent and treat conditions that may be secondary to the diagnosis.

Genetic basis to hybrid inviability is more complex than hybrid male sterility in Caenorhabditis nematodes.

Science.gov (United States)

Bundus, Joanna D; Wang, Donglin; Cutter, Asher D

2018-04-07

Hybrid male sterility often evolves before female sterility or inviability of hybrids, implying that the accumulation of divergence between separated lineages should lead hybrid male sterility to have a more polygenic basis. However, experimental evidence is mixed. Here, we use the nematodes Caenorhabditis remanei and C. latens to characterize the underlying genetic basis of asymmetric hybrid male sterility and hybrid inviability. We demonstrate that hybrid male sterility is consistent with a simple genetic basis, involving a single X-autosome incompatibility. We also show that hybrid inviability involves more genomic compartments, involving diverse nuclear-nuclear incompatibilities, a mito-nuclear incompatibility, and maternal effects. These findings demonstrate that male sensitivity to genetic perturbation may be genetically simple compared to hybrid inviability in Caenorhabditis and motivates tests of generality for the genetic architecture of hybrid incompatibility across the breadth of phylogeny.

Effects of perinatal daidzein exposure on subsequent behavior and central estrogen receptor α expression in the adult male mouse.

Science.gov (United States)

Yu, Chengjun; Tai, Fadao; Zeng, Shuangyan; Zhang, Xia

2013-06-03

Daidzein is one of the most important isoflavones present in soy and it is unique as it can be further metabolized to equol, a compound with greater estrogenic activity than other isoflavones. The potential role of daidzein in the prevention of some chronic diseases has drawn public attention and increased its consumption in human, including in pregnant women and adolescent. It is unclear whether perinatal exposure to daidzein through maternal diets affects subsequent behavior and central estrogen receptor α (ERα) expression in male adults. Following developmental exposure to daidzein through maternal diets during perinatal period, subsequent anxiety-like behavior, social behavior, spatial learning and memory of male mice at adulthood were assessed using a series of tests. The levels of central ER α expression were also examined using immunocytochemistry. Compared with the controls, adult male mice exposed to daidzein during the perinatal period showed significantly less exploration, higher levels of anxiety and aggression. They also displayed more social investigation for females and a tendency to improve spatial learning and memory. The mice with this early daidzein treatment demonstrated significantly higher levels of ERα expression in several brain regions such as the bed nucleus of the stria terminalis, medial preoptic, arcuate hypothalamic nucleus and central amygdaloid mucleus, but decreased it in the lateral septum. Our results indicated that perinatal exposure to daidzein enhanced masculinization on male behaviors which is assocciated with alterations in ERα expression levels led by perinatal daidzein exposure. Copyright © 2012 Elsevier Inc. All rights reserved.

Rutting behaviour of territorial and nonterritorial male chamois: is there a home advantage?

Science.gov (United States)

Corlatti, Luca; Caroli, Martina; Pietrocini, Venusta; Lovari, Sandro

2013-01-01

Males using alternative male mating tactics (AMTs) may express their mating effort in a variety of ways. In polygynous species with limited sexual dimorphism, differences in male aggressiveness may affect mating opportunities. We recorded the behaviour of 8 territorial and 7 nonterritorial male Alpine chamois Rupicapra rupicapra, a nearly monomorphic ungulate, during the 2011 rut in the Gran Paradiso National Park (Italy), to analyse differences in mating effort and mating opportunities between AMTs. The chamois showed a rich behavioural repertoire (31 behavioural patterns), with a prevalence of indirect aggression. Territorial males had higher frequency of aggressive and courtship behaviour than nonterritorial males over the early rut. Later, nonterritorials increased their mating effort, possibly because of reduced competition with dominant males. Territorial males monopolised all observed mating events. Our results support the hypothesis that chamois may assert dominance through intense aggressiveness rather than through horn size or body mass as found in other polygynous ungulates. Most important, differences in mating effort mediated by AMTs resulted in different mating opportunities; these benefits, however, are traded off against greater costs, due to higher levels of hormone metabolites and parasitism. Data on AMTs flexibility, lifetime reproductive success and survival are needed to clarify the mechanisms underlying the evolution and maintenance of AMTs within chamois populations. Copyright © 2012 Elsevier B.V. All rights reserved.

An explanation of the 25% male excess mortality for all children under 5

Directory of Open Access Journals (Sweden)

Mage David T.

2015-12-01

Full Text Available BACKGROUND: To demonstrate that an epidemiologic probability model of a hypothesized X-linkage for Sudden Infant Death Syndrome (SIDS that predicted its 50% male excess, also predicts the 25% male excess of all child mortality for ages under 5 years.

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

Science.gov (United States)

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.

Antiaggressive activity of central oxytocin in male rats

NARCIS (Netherlands)

Calcagnoli, F.; de Boer, S.F.; Althaus, M.; den Boer, J.A.; Koolhaas, J.M.

2013-01-01

A substantial body of research suggests that the neuropeptide oxytocin promotes social affiliative behaviors in a wide range of animals including humans. However, its antiaggressive action has not been unequivocally demonstrated in male laboratory rodents. Our primary goal was to examine the

Attitudes, Knowledge, and Behavior Regarding Condom Use in Urban Black Adolescent Males.

Science.gov (United States)

Wilson, Michele D.; And Others

1994-01-01

Examined male adolescent behavior, attitudes, and knowledge concerning condom use. Findings from 241 sexually active black adolescent males revealed that factors associated with condom use included higher grade level, having 2 or more sexual partners in past 6 months, communication about contraception with sexual partner, desire for sexually…

Male-only clinics: a success story in Colombia.

Science.gov (United States)

Goldman, R

1987-04-01

2 male-only reproductive health clinics in Colombia are refuting the stereotype that Latin American men reject vasectomy as a threat to their machismo image and consider birth control to be a woman's responsibility. Over 1000 vasectomies were performed in the 2 clinics in Bogota and Medellin in 1986. The clinics are operated by PROFAMILIA and supported by the Association for Voluntary Surgical Contraception. Information about these male-only clinics is dispersed through radio announcements, magazine advertisements, and newspaper articles. The cost of services at these clinics is 50% less than services provided at other family facilities. These clinics demonstrate that Colombian men are willing to share family planning responsibilities if services are offered in a manner respectful of their needs. 3 additional male-only clinics are scheduled to open in Colombia in 1987.

Correlates of androgens in wild male Barbary macaques: Testing the challenge hypothesis.

Science.gov (United States)

Rincon, Alan V; Maréchal, Laëtitia; Semple, Stuart; Majolo, Bonaventura; MacLarnon, Ann

2017-10-01

Investigating causes and consequences of variation in hormonal expression is a key focus in behavioral ecology. Many studies have explored patterns of secretion of the androgen testosterone in male vertebrates, using the challenge hypothesis (Wingfield, Hegner, Dufty, & Ball, 1990; The American Naturalist, 136(6), 829-846) as a theoretical framework. Rather than the classic association of testosterone with male sexual behavior, this hypothesis predicts that high levels of testosterone are associated with male-male reproductive competition but also inhibit paternal care. The hypothesis was originally developed for birds, and subsequently tested in other vertebrate taxa, including primates. Such studies have explored the link between testosterone and reproductive aggression as well as other measures of mating competition, or between testosterone and aspects of male behavior related to the presence of infants. Very few studies have simultaneously investigated the links between testosterone and male aggression, other aspects of mating competition and infant-related behavior. We tested predictions derived from the challenge hypothesis in wild male Barbary macaques (Macaca sylvanus), a species with marked breeding seasonality and high levels of male-infant affiliation, providing a powerful test of this theoretical framework. Over 11 months, 251 hr of behavioral observations and 296 fecal samples were collected from seven adult males in the Middle Atlas Mountains, Morocco. Fecal androgen levels rose before the onset of the mating season, during a period of rank instability, and were positively related to group mating activity across the mating season. Androgen levels were unrelated to rates of male-male aggression in any period, but higher ranked males had higher levels in both the mating season and in the period of rank instability. Lower androgen levels were associated with increased rates of male-infant grooming during the mating and unstable periods. Our results

Student Enrolment in Malaysian Higher Education: Is There Gender Disparity and What Can We Learn from the Disparity?

Science.gov (United States)

Wan, Chang-Da

2018-01-01

Access into higher education has traditionally been dominated by males. However, the current situation in Malaysia as well as in many developed and developing nations is that females have outnumbered males in higher education. By comparing gender enrolment, this paper illustrates the extent of gender disparity in Malaysian higher education across…

Signature Concepts of Women Researchers in Higher Education Teaching and Learning

Science.gov (United States)

Kandlbinder, Peter

2014-01-01

The history of research into higher education teaching and learning has been one led by male researchers. Individual women researchers have always been active in the field but their contributions have not received the same level of recognition as their male counterparts. A review of the research literature in journals focused on teaching and…

Effects of fetal exposure to gamma rays on aggressive behavior in adult male mice

International Nuclear Information System (INIS)

Minamisawa, Takeru; Hirokaga, Kouichi; Sasaki, Shunsaku; Noda, Yutaka.

1992-01-01

Aggressive behavior (AB) in first generation (F 1 ) hybrid male C57BL/6 x C3H mice irradiated on the 14th day of gestation was studied at 100-135 days of age. Gravid female mice were irradiated with 1.0 or 2.0 Gy of gamma rays to the whole body. The AB of pairs of mice were recorded with a capacitance-induction motility monitor and on videotape. Recordings were continued for 90 min, starting at 2:00 PM. Vigorous wrestling, boxing and biting were regarded as AB. Data recorded at 15-min intervals were stored on micro-computer discs. The body weight for the irradiated group was significantly lower than that for the control group. The number of instances of AB was significantly higher in the irradiated group. The AB of the 2.0 Gy group was significantly more intensive than that of the control group. No difference in the duration of AB was found for the 2 irradiated and the control groups. Results demonstrate that male mice irradiated prenatally show increased aggressiveness. (author)

Heat stress affects male reproduction in a parasitoid wasp.

Science.gov (United States)

Nguyen, Thanh Manh; Bressac, Christophe; Chevrier, Claude

2013-03-01

In insects, reproductive success and survival are affected by temperature. Reproduction is more sensitive than other physiological traits. While the effects of heat stress on females are well known, the effects on males are less clear. Hymenopteran parasitoids are valuable for studying the consequences of heat stress on male reproduction. In these species, through arrhenotoquous parthenogenesis, the sex ratio of the offspring is directly dependent on the sperm stock acquired by females during copulation. In the lab, heat temperature treatments (32-44°C) were applied for 3 days in the pupal stage of Anisopteromalus calandrae males, and development was completed at 30°C. Three different effects were observed depending on the temperature: mortality above 42°C, sterility of emerging males at 40°C, and sub-fertility at 38°C. This sub-fertility is characterized by a dramatic decrease in male sperm supplies, of up to 7% compared to control males. In the course of ageing, the sperm stock of sub-fertile males increases but never reaches the level of control males. Survival was significantly higher in control (30°C) males than those treated at 38°C. Male mating ability was similar whatever the treatment (control and 38°C), but females mated with 38°C-treated males stored 100 times less sperm on average than those mated with control males. The offspring sex ratio of females mated with 38°C-treated males was strongly male biased. The physiological mechanisms are as yet unknown. The relationship between temperature, sperm stock and sex ratio should be taken into account in the management of parasitoids for integrated pest management. Copyright © 2012 Elsevier Ltd. All rights reserved.

Use of the adjustable trans-obturator male sling system for the treatment of male incontinence. An initial experience

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M.S. El Badry

2016-06-01

Conclusions: Our early experience demonstrated that the ATOMS system may be a safe and effective procedure for the treatment of male urinary incontinence. It has the advantage of being feasible any time after an operation when necessary. However, long-term follow-up on a large number of cases is required to ensure its long-term efficacy and safety.

Alternative routes to the leader male role in a multi-level society: follower vs. solitary male strategies and outcomes in hamadryas baboons.

Science.gov (United States)

Pines, Mathew; Saunders, Julian; Swedell, Larissa

2011-07-01

The nested one-male units (OMUs) of the hamadryas baboon are part of a complex social system in which "leader" males achieve near exclusive mating access by forcibly herding females into permanent consortships. Within this multi-level social system (troops, bands, clans and OMUs) are two types of prereproductive males--the follower and solitary male--whose different trajectories converge on the leader role. Here we compare OMU formation strategies of followers, who associate with a particular OMU and may have social access to females, with those of solitary males, who move freely within the band and do not associate regularly with OMUs. Data were derived from 42 OMU formations (16 by followers and 26 by solitary males) occurring over 8 years in a hamadryas baboon band at the Filoha site in Ethiopia. "Initial units" (IUs) with sexually immature females (IU strategy) were formed by 44% of followers and 46% of solitary males. The remaining followers took over mature females when their leader was deposed (challenge strategy) or disappeared (opportunistic strategy), or via a seemingly peaceful transfer (inheritance strategy). Solitary males took over mature females from other clans and bands, but mainly from old, injured or vanished leaders within their clan (via both the challenge and opportunistic strategies). Former followers of an OMU were more successful at taking over females from those OMUs than any other category of male. Despite this advantage enjoyed by ex-follower leaders, ex-solitary leaders were equally capable of increasing their OMU size at a comparable rate in their first 2 years as a leader. These results demonstrate the potential for males to employ both multiple roles (follower vs. solitary male) and multiple routes (IU, inheritance, challenge, opportunistic) to acquire females and become a leader male in a mating system characterized by female defense polygyny in a competitive arena. © 2011 Wiley-Liss, Inc.

Higher order mode optical fiber Raman amplifiers

DEFF Research Database (Denmark)

Rottwitt, Karsten; Friis, Søren Michael Mørk; Usuga Castaneda, Mario A.

2016-01-01

We review higher order mode Raman amplifiers and discuss recent theoretical as well as experimental results including system demonstrations.......We review higher order mode Raman amplifiers and discuss recent theoretical as well as experimental results including system demonstrations....

Chromosome Synapsis and Recombination in Male-Sterile and Female-Fertile Interspecies Hybrids of the Dwarf Hamsters (Phodopus, Cricetidae

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Tatiana I. Bikchurina

2018-04-01

Full Text Available Hybrid sterility is an important step in the speciation process. Hybrids between dwarf hamsters Phodopus sungorus and P. campbelli provide a good model for studies in cytological and genetic mechanisms of hybrid sterility. Previous studies in hybrids detected multiple abnormalities of spermatogenesis and a high frequency of dissociation between the X and Y chromosomes at the meiotic prophase. In this study, we found that the autosomes of the hybrid males and females underwent paring and recombination as normally as their parental forms did. The male hybrids showed a significantly higher frequency of asynapsis and recombination failure between the heterochromatic arms of the X and Y chromosomes than the males of the parental species. Female hybrids as well as the females of the parental species demonstrated a high incidence of centromere misalignment at the XX bivalent and partial asynapsis of the ends of its heterochromatic arms. In all three karyotypes, recombination was completely suppressed in the heterochromatic arm of the X chromosome, where the pseudoautosomal region is located. We propose that this recombination pattern speeds up divergence of the X- and Y-linked pseudoautosomal regions between the parental species and results in their incompatibility in the male hybrids.

Developmental environment mediates male seminal protein investment in Drosophila melanogaster.

Science.gov (United States)

Wigby, Stuart; Perry, Jennifer C; Kim, Yon-Hee; Sirot, Laura K

2016-03-01

Males of many species fine-tune their ejaculates in response to sperm competition risk. Resource availability and the number of competitors during development can also strongly influence sperm production. However, despite the key role of seminal proteins in mediating reproductive processes, it is unclear whether seminal protein investment is dependent on the developmental environment.We manipulated the developmental environment of Drosophila melanogaster by rearing flies at low and high density. As expected, this resulted in large and small (i.e. high and low condition) adult phenotypes, respectively.As predicted, large males produced more of two key seminal proteins, sex peptide (SP) and ovulin, and were more successful at obtaining matings with both virgin and previously mated females. However, there was only a weak and non-significant trend for large males to transfer more absolute quantities of SP at mating, and thus, small males ejaculated proportionally more of their stored accessory gland SP resources.Males transferred more receptivity-inhibiting SP to large females. Despite this, large females remated more quickly than small females and thus responded to their developmental environment over and above the quantity of SP they received.The results are consistent with two non-mutually exclusive hypotheses. First, flies might respond to condition-dependent reproductive opportunities, with (i) small males investing heavily in ejaculates when mating opportunities arise and large males strategically partitioning SP resources and (ii) small females remating at reduced rates because they have higher mating costs or need to replenish sperm less often.Second, flies may be primed by their larval environment to deal with similar adult population densities, with (i) males perceiving high density as signalling increased competition, leading small males to invest proportionally more SP resources at mating and (ii) females perceiving high density as signalling abundant

Prosocial effects of prolactin in male rats: Social recognition, social approach and social learning.

Science.gov (United States)

Donhoffner, Mary E; Al Saleh, Samar; Schink, Olivia; Wood, Ruth I

2017-11-01

Prolactin (PRL) and oxytocin (OT) are pituitary hormones essential for lactation, but also promote sexual behavior. OT stimulates social behaviors, such as recognition, approach, and learning, but less is known about PRL in these behaviors. Since PRL and OT have complementary functions in reproduction, we hypothesized that PRL increases social recognition, approach, and learning. Male Long-Evans rats received ovine PRL (oPRL; 0.5, 2.0 or 5.0mg/kg), the PRL antagonist bromocriptine (0.1, 3.0 or 5.0mg/kg) or saline 20 mins before testing for recognition of familiar vs. unfamiliar stimulus males. Saline controls preferred the unfamiliar male (psocial approach, we determined if PRL restores approach 2h after defeat by an aggressive male. Defeated rats avoided the aggressive male. 2mg/kg oPRL, before or after defeat, restored approach towards the aggressive male (psocial learning, we tested social transmission of food preference. Rats choose between two unfamiliar flavors, one of which they have previously been exposed to through interaction with a demonstrator rat. Vehicle controls preferred chow with the demonstrated flavor over the novel flavor. oPRL-treated rats were similar. Bromocriptine-treated rats failed to show a preference. When tested one week later, only oPRL-treated rats preferred the demonstrated flavor. The results suggest that PRL is required for social recognition and learning, and that increasing PRL enhances social memory and approach, similar to OT. Copyright © 2017 Elsevier Inc. All rights reserved.

Variations in physical activity of male and female students from the Ukraine in health-promoting life style.

Science.gov (United States)

Bergier, Józef; Bergier, Barbara; Tsos, Anatolii

2017-05-11

[b]Introduction. [/b]A large-scale research was performed concerning issues relating to physical activity as an important factor in a healthy lifestyle and involved observing the differences among males and females as future elites of the Ukraine. [b]Objective. [/b]The objective of the research is to assess the physical activity of students from the Ukraine, considering such factors as: gender, leisure time, time spent sitting, sports performed or intended to be performed, and the BMI. [b]Materials and method.[/b] The extended version of the IPAQ, supplemented with 3 original questions by the authors, was applied to a 2,125-strong student group from 12 majors of the University of Luck, Ukraine. [b]Results. [/b]Students from Ukraine portrayed a positive picture of physical activity with significantly higher values in male students of both total activity and its fields, i.e. sports activity and work (studying). The male students performed better in their fitness (condition) self-assessment and the amount of time spent sitting, whereas the female students had better BMI results. Both genders differed considerably in their choice of sport-recreational activities. [b]Conclusions. [/b]Females more than males demonstrated lower indices of participation in physical activity, which did not permit the formulation of a positive assessment of their lifestyle. A positive phenomenon is the normal BMI and trace values of overweight in women, exactly the reverse to males.

Social learning in nest-building birds watching live-streaming video demonstrators.

Science.gov (United States)

Guillette, Lauren M; Healy, Susan D

2018-02-13

Determining the role that social learning plays in construction behaviours, such as nest building or tool manufacture, could be improved if more experimental control could be gained over the exact public information that is provided by the demonstrator, to the observing individual. Using video playback allows the experimenter to choose what information is provided, but will only be useful in determining the role of social learning if observers attend to, and learn from, videos in a manner that is similar to live demonstration. The goal of the current experiment was to test whether live-streamed video presentations of nest building by zebra finches Taeniopygia guttata would lead observers to copy the material choice demonstrated to them. Here, males that had not previously built a nest were given an initial preference test between materials of two colours. Those observers then watched live-stream footage of a familiar demonstrator building a nest with material of the colour that the observer did not prefer. After this experience, observers were given the chance to build a nest with materials of the two colours. Although two-thirds of the observer males preferred material of the demonstrated colour after viewing the demonstrator build a nest with material of that colour more than they had previously, their preference for the demonstrated material was not as strong as that of observers that had viewed live demonstrator builders in a previous experiment. Our results suggest researchers should proceed with caution before using video demonstration in tests of social learning. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Characteristics of upper limb muscular strength in male wheelchair tennis players

Science.gov (United States)

Moon, Hyo-Bin; Park, Seung-Jae; Kim, Al-Chan; Jang, Jee-Hun

2013-01-01

The purpose of this study was to identify the characteristics of muscular strength in upper limb and to present the preliminary information for development of sports injury prevention program and exercise rehabilitation program in wheelchair tennis players. Participants were 12 male wheelchair tennis players. Muscular strength was measured in shoulder and elbow joints with isokinetic dynamometer. Ipsilateral (IR) and bilateral (BR) balance ratio were calculated with isokinetic strength at 60°/sec. As a result, extension strength (ES) was significantly higher than flexion strength (FS) (Pelbow joint FS was significantly higher than ES (Pelbow joints and lower IR and BR in elbow joints could be the characteristics in male wheelchair tennis players. It is suggested that flexor strengthening program in nondominant shoulder joint, extensor strengthening program in both elbow joint, and flexor strengthening program in non-dominant elbow joint should be introduced for male wheelchair tennis players. PMID:24278887

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

Science.gov (United States)

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.

Sexual Experience Enhances Drosophila melanogaster Male Mating Behavior and Success

Science.gov (United States)

Saleem, Sehresh; Ruggles, Patrick H.; Abbott, Wiley K.; Carney, Ginger E.

2014-01-01

Competition for mates is a wide-spread phenomenon affecting individual reproductive success. The ability of animals to adjust their behaviors in response to changing social environment is important and well documented. Drosophila melanogaster males compete with one another for matings with females and modify their reproductive behaviors based on prior social interactions. However, it remains to be determined how male social experience that culminates in mating with a female impacts subsequent male reproductive behaviors and mating success. Here we show that sexual experience enhances future mating success. Previously mated D. melanogaster males adjust their courtship behaviors and out-compete sexually inexperienced males for copulations. Interestingly, courtship experience alone is not sufficient in providing this competitive advantage, indicating that copulation plays a role in reinforcing this social learning. We also show that females use their sense of hearing to preferentially mate with experienced males when given a choice. Our results demonstrate the ability of previously mated males to learn from their positive sexual experiences and adjust their behaviors to gain a mating advantage. These experienced-based changes in behavior reveal strategies that animals likely use to increase their fecundity in natural competitive environments. PMID:24805129

Sexual experience enhances Drosophila melanogaster male mating behavior and success.

Directory of Open Access Journals (Sweden)

Sehresh Saleem

Full Text Available Competition for mates is a wide-spread phenomenon affecting individual reproductive success. The ability of animals to adjust their behaviors in response to changing social environment is important and well documented. Drosophila melanogaster males compete with one another for matings with females and modify their reproductive behaviors based on prior social interactions. However, it remains to be determined how male social experience that culminates in mating with a female impacts subsequent male reproductive behaviors and mating success. Here we show that sexual experience enhances future mating success. Previously mated D. melanogaster males adjust their courtship behaviors and out-compete sexually inexperienced males for copulations. Interestingly, courtship experience alone is not sufficient in providing this competitive advantage, indicating that copulation plays a role in reinforcing this social learning. We also show that females use their sense of hearing to preferentially mate with experienced males when given a choice. Our results demonstrate the ability of previously mated males to learn from their positive sexual experiences and adjust their behaviors to gain a mating advantage. These experienced-based changes in behavior reveal strategies that animals likely use to increase their fecundity in natural competitive environments.

Chemical Quality of Male Etawah Crossbred and Castrated Boer Crossbred Goat Meat

Directory of Open Access Journals (Sweden)

Djalal Rosyidi

2012-02-01

Full Text Available The aim of this study was to know the chemical quality (moisture, protein, fat, calcium, phosphorus of male Etawah crossbred and castrated Boer crossbred goat meat. The result expected can be used as further information about the chemical quality of male Etawah crossbred and castrated Boer crossbred goat meat and as future researches. The material of the research were loin meat, front and back thigh of male Etawah crossbred and castrated Boer crossbred goat, these meat parts were the fineground and 10 gram were taken for sample preparation. The result show that the different species of goat statistically was no significant effect (P>0.05 on moisture, protein, fat, calcium and  phosphorus. The chemical quality of male Etawah crossbred and castrated Boer crossbred goat (moisture obtained from vacuum oven, fat from soxhlet, protein from semimicro kejldahl, calcium and phosphorus from Spectrophotometer is (71.080%, 69.886%; 17.120%, 17.907%; 8.358%, 8.981%; 13.846 mg/100g, 18.811mg/100g; 134.817mg/100g, 151.032mg/100g. The conclusion was moisture content from male Etawah crossbred was higher than castrated Boer crossbred, but fat, protein, calcium, and phosphorus content castrated Boer crossbred were higher than castrated Boer crossbred.   Keywords: male Etawah crossbred, castrated Boer crossbred, moisture

Males exceed females in PCB concentrations of cisco (Coregonus artedi) from Lake Superior

Science.gov (United States)

Madenjian, Charles P.; Yule, Daniel L.; Chernyak, Sergei M.; Begnoche, Linda J.; Berglund, Eric K.; Isaac, Edmund J.

2014-01-01

We determined whole-fish polychlorinated biphenyl (PCB) concentrations of 25 male and 25 female age-7 ciscoes (Coregonus artedi) captured from a spawning aggregation in Thunder Bay, Lake Superior, during November 2010. We also determined PCB concentrations in the ovaries and somatic tissue of five additional female ciscoes (ages 5–22). All 55 of these ciscoes were in ripe or nearly ripe condition. Bioenergetics modeling was used to determine the contribution of the growth dilution effect toward a difference in PCB concentrations between the sexes, as females grew substantially faster than males. Results showed that the PCB concentration of males (mean = 141 ng/g) was 43% greater than that of females (mean = 98 ng/g), and this difference was highly significant (P ovaries and the somatic tissue of the five females were 135 and 100 ng/g, respectively. Based on these PCB determinations for the ovaries and somatic tissue, we concluded that release of eggs by females at previous spawnings was not a contributing factor to the observed difference in PCB concentrations between the sexes. Bioenergetics modeling results indicated that the growth dilution effect could explain males being higher than females in PCB concentration by only 3–7%. We concluded that the higher PCB concentration in males was most likely due to higher rate of energy expenditure, originating from greater activity and a higher resting metabolic rate. Mean PCB concentration in the cisco eggs was well below the U. S. Food and Drug Administration and Ontario Ministry of Environment guidelines of 2000 and 844 ng/g, respectively, and this finding may have implications for the cisco roe fishery currently operating in Lake Superior.

Study on Quality Improvement Effect and Separate Character of Soybean Male Sterile (MS1) Recurrent Selection Population

Institute of Scientific and Technical Information of China (English)

ZHAO Shuang-jin; ZHANG Meng-chen; JIANG Chun-zhi; YANG Chun-yan; LIU Bing-qiang; CUI Jue

2007-01-01

To solve the problem that soybean has narrow genetic base, we constructed a series of male sterile recurrent selection populations, and studied the effects of quality improvement and practical value. An LD-base population, which fits to our ecology type was constructed by 6 years' gene enrichment through the introduction of new genes from 23 local varieties and recurrent selection. The LD-base populations were then improved by making crosses with high protein and high oil genotypes. As a result we obtained a high protein sub-population (db) and a high oil sub-population (gy). For the db sub-population, the protein content is 1.18% higher than the base population, 22.38% of the individuals contain 45% or more of protein, which is 10.99% higher than the base population. For the gy sub-population, oil content is 0.24% higher than the base population. Individuals with oil content of 20% or more are 11.05% higher than the base population. The quantitative characters such as flowering date, mature date, pod habit, and hilum color, etc., all showed wide range of separation, and the segregation ratio approached balance. The c.v. of branch number of ms1 recurrent population (72.8%) is higher than general cross-population (57.3%), and the c.v. of 100 seed weight of ms1 (18.1%) is higher than general cross population (16.5%), the coefficient of variation of plant height, pods per plant, and seeds per pod were not significantly different. It was demonstrated in this paper that the quality character of ms1 male sterile recurrent selection population was improved by adding new genes. And the segregation of other characters widened, making the populations suitable for the objective of soybean breeding. In this paper, we also discussed the breeding method, key technology, and selection effect of soybean ms1 population.

Male batterers' alcohol use and gambling behavior.

Science.gov (United States)

Brasfield, Hope; Febres, Jeniimarie; Shorey, Ryan; Strong, David; Ninnemann, Andrew; Elmquist, Joanna; Andersen, Shawna M; Bucossi, Meggan; Schonbrun, Yael C; Temple, Jeff R; Stuart, Gregory L

2012-03-01

Little work has examined the interrelations among intimate partner violence (IPV), alcohol use, and gambling behavior, and no studies have examined these relationships among males court-ordered to batterer intervention programs (BIPs). The aim of the current investigation was to explore the associations between IPV, alcohol use, and gambling behavior among 341 males court-mandated to attend BIPs utilizing self-report measures. Voluntary, anonymous questionnaires were administered and completed during regularly scheduled BIP sessions. Compared to the general population, a higher percentage of the sample met criteria for pathological gambling (9%), and problem gambling (17%). Further, males exhibiting pathological gambling were more likely to be hazardous drinkers, and hazardous drinkers were more likely to exhibit pathological gambling. Additionally, pathological gamblers were at an increased risk for the perpetration of both physical and sexual aggression. Finally, gambling behavior uniquely predicted the perpetration of sexual aggression above and beyond alcohol use, impulsivity, and relationship satisfaction. The implications of these results for future research and intervention are discussed.

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.

Testosterone and cortisol responses in male soccer players: The effect of home and away venues.

Science.gov (United States)

Fothergill, Melissa; Wolfson, Sandy; Neave, Nick

2017-08-01

The present studies examined the influence of playing venue on psychobiological responses in male soccer players. Many studies have demonstrated the existence of a home advantage, wherein teams perform better at home than away. A recent focus has attempted to explain this advantage from a psychobiological perspective, with studies showing hormonal differences with regard to venue, game outcome, dominance and perceived stress. Two studies investigated testosterone and cortisol responses in relation to home and away venues. In an initial study of 18 male elite Premier League academy soccer players (age, 17.47, SD, 64), salivary cortisol levels were monitored in two competitive matches, both at home and away. Higher post-game cortisol levels were observed at home (p=0.002), with the team winning all its games. In a second study involving a 12 semi-professional group of players (age, 23.17, SD, 3.8), the same post-game cortisol findings at home were replicated (p=0.001), with this team losing all its games. No effects were observed for testosterone in either study. The results extend earlier research findings on the complex relationship which surrounds the psychobiological impact on the home advantage. The findings suggest that higher levels of stress are experienced by home players in their home matches. Copyright © 2017 Elsevier Inc. All rights reserved.

SEMINAL PLASMA LEVELS OF LEAD AND MERCURY IN INFERTILE MALES IN BENIN CITY, NIGERIA

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Emokpae MA

2016-01-01

Full Text Available Background/objectives: Studies on environmental exposure to toxic metals and their effects on male reproductive function are scare in our setting. This study evaluates the levels of lead and mercury in seminal plasma of infertile males who are non-occupationally exposed in Benin City, Nigeria and to determine the relationship between seminal quality and these toxic metals. Materials and Methods: A total of 80 subjects participated in this study which includes 60 infertile males on routine visit to the infertility clinics in Benin City and 20 fertile males as controls. The concentration of lead in seminal plasma was assayed by atomic absorption spectrophotometer while the concentration of mercury was measured using inductively coupled plasma Mass spectrometry. Semen analyses were performed using standard techniques as recommended by World Health Organization. Results: Mean seminal plasma lead and mercury levels were significantly higher (p<0.001 in infertile males compared with controls. Mercury and lead correlated negatively (p<0.001 with sperm count, progressive motility, total motility and morphology but not with semen volume. There was no significant correlation between toxic metals and sperm indices in fertile males (controls. Conclusion: The levels of the studied toxic metals were higher in seminal plasma of infertile males and appear to have adverse effect on seminal indices in non -occupationally exposed males.

Papain-induced experimental pulmonary emphysema in male and female mice.

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Machado, Mariana Nascimento; Figueirôa, Silviane Fernandes da Silva; Mazzoli-Rocha, Flavia; Valença, Samuel dos Santos; Zin, Walter Araújo

2014-08-15

In papain-induced models of emphysema, despite the existing extensive description of the cellular and molecular aspects therein involved, sexual hormones may play a complex and still not fully understood role. Hence, we aimed at exploring the putative gender-related differences in lung mechanics, histology and oxidative stress in papain-exposed mice. Thirty adult BALB/c mice received intratracheally either saline (50 μL) or papain (10 U/50 μL saline) once a week for 2 weeks. In males papain increased lung resistive and viscoelastic/inhomogeneous pressures, static elastance, and viscoelastic component of elastance, while females showed higher static elastance and resistive pressure only. Both genders presented similar higher parenchymal cellularity and mean alveolar diameter, and less collagen-elastic fiber content and body weight gain than their respective controls. Increased functional residual capacity was more prominent in males. Female papain-treated mice were more susceptible to oxidative stress. Thus, male and female papain-exposed mice respond differently, which should be carefully considered to avoid confounding results. Copyright © 2014 Elsevier B.V. All rights reserved.

Reproductive health of male radiographers

International Nuclear Information System (INIS)

Shakhatreh, Farouk M.

2001-01-01

To compare certain reproductive health problems reported in 2 groups of males, one of which was exposed to x-ray radiation (radiographers) and the other group that was not exposed to x-ray radiation. The reproductive health problems were miscarriage, congenital anomalies, still births and infertility. Two groups of men were selected (90 in each group). The first group consisted of radiographers and the other groups consisted of men not exposed to x-ray radiation. The 2 groups were matched for age and source. Relative risk, attributable risk percentage and level of significance were calculated. Incidence rate of reproductive health problems was increasing with the increase in duration of exposure to x-ray radiation ranging between 17% (for those exposed for 1-5 years) to 91% (for those exposed for more than 15 years). There were significant associations between exposure to radiation and miscarriage (relative risk = 1.67, attributable risk percentage = 40%), congenital anomalies (relative risk = 10, attributable risk percentage 90%), still birth (relative risk = 7, attributable risk percentage = 86%), and infertility (relative risk = 4.5, attributable risk = 78%). The incidence rates of reproductive health problems reported by male radiographers were significantly higher than that reported by the non exposed group and higher than the incidence rates reported in community-based studies in Jordan. The incidence rates of fetal death (miscarriage and stillbirth together) and infertility reported by our radiographers were higher than had been reported by the British radiographers. An immediate plan of action is needed to protect our radiographers. Further studies are needed in this field taking into account all extraneous variables that may affect the reproductive health of radiographers. (author)

Home ranges and satellite tactics of male green swordtails (Xiphophorus helleri) in nature.

Science.gov (United States)

Franck, D; Klamroth, B; Taebel-Hellwig, A; Schartl, M

1998-05-01

Dominance relationships were studied between marked or otherwise individually recognizable male green swordtails in a creek at Lake Catemaco and in a tributary of the Rio Atoyac (Veracruz, Mexico). The Atoyac population is unique because of a high degree of polymorphism, including both macromelanophore spotting and a micromelanophore tailspot pattern. During the dry season males living in the same area maintained a linear social hierarchy for periods of many days. The subordinate males settled down either in the same home ranges or in home ranges largely overlapping with that of dominant males. Although dominant males untiringly chased the subordinate males away, they returned persistently and achieved the status of non-tolerated satellites. Females were less stationary and presumably passed through many male home ranges during their feeding activities. The data clearly demonstrate that green swordtails live in complex social systems in which male-male competition and probably also female mate choice are likely to be essential factors for individual reproductive success.

Male attitudes to family planning education in Santiago, Chile.

Science.gov (United States)

Hall, M F

1977-01-01

Male attitudes toward family planning education were assessed through a study of 720 men in Santiago and 240 men in a nearby rural area of Chile. Interviews were conducted by male students at the University of Chile School of Public Health. A large majority of the men were using or planned to use contraception in the future. There was a near consensus that adults should be informed regarding family planning. More than a majority of the respondents favored provision of contraceptive information for unmarried women, but most did not approve of premarital sexual activity for females. Most respondents favored the teaching of sex education in schools "according to the age of the children." Younger and higher class males tended to hold the most liberal attitudes.

Androgen deficiency in the aging male and chronic prostatitis: clinical and diagnostic comparative analysis

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Spirin Р.V.

2013-03-01

Full Text Available The research goal is to study probability, period of development and characteristics of a clinical course of chronic prostatitis against the background of androgen deficiency in the aging male. Materials and methods: The Aging Male Symptoms (AMS rating scale has been applied for androgen deficiency evaluation and the International Prostate Symptom Score (IPSS — for chronic prostatitis evaluation. 57 men with chronic prostatitis in combination with androgen deficiency in the aging male have been examined. Results: It has been concluded that the development of chronic prostatitis against the background of androgen deficiency in the aging male occurs in a shorter time period and about 1.5 times more frequently compared to androgen deficiency in the aging male at the background of chronic prostatitis. The analysis of time periods between the onset of chronic prostatitis symptoms against the background of androgen deficiency in the aging male and androgen deficiency in the aging male symptoms against the background of chronic prostatitis showed that androgen deficiency in the aging male symptoms have been revealed 1-2 years earlier than the onset of chronic prostatitis. The development of androgen deficiency in the aging male against the background of chronic prostatitis has showed a backward tendency. Signs of chronic prostatitis have been more frequently occurred in a period of four-five years earlier the androgen deficiency in the aging male development. Conclusion: The risk of development of chronic prostatitis against the background of androgen deficiency in the aging male during the next two years is actually four times higher in comparison with the development of androgen deficiency in the aging male against the background of chronic prostatitis. According to the International Prostate Symptom Score (IPSS, patients with chronic prostatitis in combination with androgen deficiency in the aging male showed higher degree of severity than

Health issues in the Arab American community. Male infertility in Lebanon: a case-controlled study.

Science.gov (United States)

Kobeissi, Loulou; Inhorn, Marcia C

2007-01-01

The impact of risk factors, such as consanguinity and familial clustering, reproductive infections, traumas, and diseases, lifestyle factors and occupational and war exposures on male infertility, was investigated in a case-controlled study conducted in Lebanon. One-hundred-twenty males and 100 controls of Lebanese, Syrian or Lebanese-Palestinian descents were selected from two in-vitro fertilization (IVF) clinics located in Beirut, Lebanon. All cases suffered from impaired sperm count and function, according to World Health Organization guidelines for semen analysis. Controls were the fertile husbands of infertile women. Data were collected using a semi-structured interview, laboratory blood testing and the results of the most recent semen analysis. Univariate, bivariate and multivariate logistic regression analyses were used for data analysis, along with checks for effect modification and control of confounders. Consanguinity and the familial clustering of male infertility cases, as well as reproductive illnesses and war exposures were independently significant risk factors for male infertility. The odds of having infertility problems in the immediate family were 2.6 times higher in cases than controls. The odds of reproductive illness were 2 times higher in cases than controls. The odds of war exposures were 1.57 times higher in cases than controls. Occupational exposures, such as smoking and caffeine intake, were not shown to be important risk factors. This case-controlled study highlights the importance of investigating the etiology of male infertility in Middle Eastern communities. It suggests the need to expand research on male reproductive health in the Middle East in order to improve the prevention and management of male infertility and other male reproductive health problems.

Sensory integration regulating male courtship behavior in Drosophila.

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Dimitrije Krstic

Full Text Available The courtship behavior of Drosophila melanogaster serves as an excellent model system to study how complex innate behaviors are controlled by the nervous system. To understand how the underlying neural network controls this behavior, it is not sufficient to unravel its architecture, but also crucial to decipher its logic. By systematic analysis of how variations in sensory inputs alter the courtship behavior of a naïve male in the single-choice courtship paradigm, we derive a model describing the logic of the network that integrates the various sensory stimuli and elicits this complex innate behavior. This approach and the model derived from it distinguish (i between initiation and maintenance of courtship, (ii between courtship in daylight and in the dark, where the male uses a scanning strategy to retrieve the decamping female, and (iii between courtship towards receptive virgin females and mature males. The last distinction demonstrates that sexual orientation of the courting male, in the absence of discriminatory visual cues, depends on the integration of gustatory and behavioral feedback inputs, but not on olfactory signals from the courted animal. The model will complement studies on the connectivity and intrinsic properties of the neurons forming the circuitry that regulates male courtship behavior.

Male density affects large-male advantage in the golden silk spider, Nephila clavipes

OpenAIRE

Clare C. Rittschof

2010-01-01

Across a variety of animal taxa, the outcome of male--male contests depends on male body size; winners are usually the larger males or the males with bigger weapons. However, high male density can either increase or reverse large-male advantage because density changes the frequency and intensity of male--male interactions. In the golden orb-web spider Nephila clavipes, large males have a competitive advantage in male--male contests. However, this species shows more than 2-fold variation in ma...

Transgenerational effect of the endocrine disruptor vinclozolin on male spermatogenesis.

Science.gov (United States)

Anway, Matthew D; Memon, Mushtaq A; Uzumcu, Mehmet; Skinner, Michael K

2006-01-01

The current study was designed to examine the actions of a model endocrine disruptor on embryonic testis development and male fertility. Pregnant rats (F0) that received a transient embryonic exposure to an environmental endocrine disruptor, vinclozolin, had male offspring (F1) with reduced spermatogenic capacity. The reduced spermatogenetic capacity observed in the F1 male offspring was transmitted to the subsequent generations (F2-F4). The administration of vinclozolin, an androgen receptor antagonist, at 100 mg/kg/day from embryonic day 8-14 (E8-E14) of pregnancy to only the F0 dam resulted in a transgenerational phenotype in the subsequent male offspring in the F1-F4 generations. The litter size and male/female sex ratios were similar in controls and the vinclozolin generations. The average testes/body weight index of the postnatal day 60 (P60) males was not significantly different in the vinclozolin-treated generations compared to the controls. However, the testicular spermatid number, as well as the epididymal sperm number and motility, were significantly reduced in the vinclozolin generations compared to the control animals. Postnatal day 20 (P20) testis from the vinclozolin F2 generation had no morphological abnormalities, but did have an increase in spermatogenic cell apoptosis. Although the P60 testis morphology was predominantly normal, the germ cell apoptosis was significantly increased in the testes cross sections of animals from the vinclozolin generations. The increase in apoptosis was stage-specific in the testis, with tubules at stages IX-XIV having the highest increase in apoptotic germ cells. The tubules at stages I-V also had an increase in apoptotic germ cells compared to the control samples, but tubules at stages VI-VIII had no increase in apoptotic germ cells. An outcross of a vinclozolin generation male with a wild-type female demonstrated that the reduced spermatogenic cell phenotype was transmitted through the male germ line. An outcross

Novel roles of Pkd2 in male reproductive system development

OpenAIRE

Nie, Xuguang; Arend, Lois J

2014-01-01

Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common inherited genetic diseases, caused by mutations in PKD1 and/ or PKD2. Infertility and reproductive tract abnormalities in male ADPKD patients are very common and have higher incidence than in the general population. In this work, we reveal novel roles of Pkd2 for male reproductive system development. Disruption of Pkd2 caused dilation of mesonephric tubules/efferent ducts, failure of epididymal coiling, and defecti...

The evolution of gonad expenditure and gonadosomatic index (GSI) in male and female broadcast-spawning invertebrates.

Science.gov (United States)

Parker, Geoff A; Ramm, Steven A; Lehtonen, Jussi; Henshaw, Jonathan M

2018-05-01

Sedentary broadcast-spawning marine invertebrates, which release both eggs and sperm into the water for fertilization, are of special interest for sexual selection studies. They provide unique insight into the early stages of the evolutionary succession leading to the often-intense operation of both pre- and post-mating sexual selection in mobile gonochorists. Since they are sessile or only weakly mobile, adults can interact only to a limited extent with other adults and with their own fertilized offspring. They are consequently subject mainly to selection on gamete production and gamete success, and so high gonad expenditure is expected in both sexes. We review literature on gonadosomatic index (GSI; the proportion of body tissue devoted to gamete production) of gonochoristic broadcast spawners, which we use as a proxy for gonad expenditure. We show that such taxa most often have a high GSI that is approximately equal in both sexes. When GSI is asymmetric, female GSI usually exceeds male GSI, at least in echinoderms (the majority of species recorded). Intriguingly, though, higher male GSI also occurs in some species and appears more common than female-biased GSI in certain orders of gastropod molluscs. Our limited data also suggest that higher male GSI may be the prevalent pattern in sperm casters (where only males release gametes). We explore how selection might have shaped these patterns using game theoretic models for gonad expenditure that consider possible trade-offs with (i) somatic maintenance or (ii) growth, while also considering sperm competition, sperm limitation, and polyspermy. Our models of the trade-off between somatic tissue (which increases survival) and gonad (which increases reproductive success) predict that GSI should be equal for the two sexes when sperm competition is intense, as is probably common in broadcast spawners due to synchronous spawning in aggregations. Higher female GSI occurs under low sperm competition. Sperm limitation appears

Male Wistar rats show individual differences in an animal model of conformity.

Science.gov (United States)

Jolles, Jolle W; de Visser, Leonie; van den Bos, Ruud

2011-09-01

Conformity refers to the act of changing one's behaviour to match that of others. Recent studies in humans have shown that individual differences exist in conformity and that these differences are related to differences in neuronal activity. To understand the neuronal mechanisms in more detail, animal tests to assess conformity are needed. Here, we used a test of conformity in rats that has previously been evaluated in female, but not male, rats and assessed the nature of individual differences in conformity. Male Wistar rats were given the opportunity to learn that two diets differed in palatability. They were subsequently exposed to a demonstrator that had consumed the less palatable food. Thereafter, they were exposed to the same diets again. Just like female rats, male rats decreased their preference for the more palatable food after interaction with demonstrator rats that had eaten the less palatable food. Individual differences existed for this shift, which were only weakly related to an interaction between their own initial preference and the amount consumed by the demonstrator rat. The data show that this conformity test in rats is a promising tool to study the neurobiology of conformity.

Association between the JC polyomavirus infection and male infertility.

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Manola Comar

Full Text Available In recent years the incidence of male infertility has increased. Many risk factors have been taken into consideration, including viral infections. Investigations into viral agents and male infertility have mainly been focused on human papillomaviruses, while no reports have been published on polyomaviruses and male infertility. The aim of this study was to verify whether JC virus and BK virus are associated with male infertility. Matched semen and urine samples from 106 infertile males and 100 fertile males, as controls, were analyzed. Specific PCR analyses were carried out to detect and quantify large T (Tag coding sequences of JCV and BKV. DNA sequencing, carried out in Tag JCV-positive samples, was addressed to viral protein 1 (VP1 coding sequences. The prevalence of JCV Tag sequences in semen and urine samples from infertile males was 34% (72/212, whereas the BKV prevalence was 0.94% (2/212. Specifically, JCV Tag sequences were detected in 24.5% (26/106 of semen and 43.4% (46/106 of urine samples from infertile men. In semen and urine samples from controls the prevalence was 11% and 28%, respectively. A statistically significant difference (p<0.05 in JCV prevalence was disclosed in semen and urine samples of cases vs. controls. A higher JC viral DNA load was detected in samples from infertile males than in controls. In samples from infertile males the JC virus type 2 strain, subtype 2b, was more prevalent than ubiquitous type 1. JCV type 2 strain infection has been found to be associated with male infertility. These data suggest that the JC virus should be taken into consideration as an infectious agent which is responsible for male infertility.

Males exceed females in PCB concentrations of cisco (Coregonus artedi) from Lake Superior.

Science.gov (United States)

Madenjian, Charles P; Yule, Daniel L; Chernyak, Sergei M; Begnoche, Linda J; Berglund, Eric K; Isaac, Edmund J

2014-09-15

We determined whole-fish polychlorinated biphenyl (PCB) concentrations of 25 male and 25 female age-7 ciscoes (Coregonus artedi) captured from a spawning aggregation in Thunder Bay, Lake Superior, during November 2010. We also determined PCB concentrations in the ovaries and somatic tissue of five additional female ciscoes (ages 5-22). All 55 of these ciscoes were in ripe or nearly ripe condition. Bioenergetics modeling was used to determine the contribution of the growth dilution effect toward a difference in PCB concentrations between the sexes, as females grew substantially faster than males. Results showed that the PCB concentration of males (mean = 141 ng/g) was 43% greater than that of females (mean = 98 ng/g), and this difference was highly significant (PPCB concentrations in the ovaries and the somatic tissue of the five females were 135 and 100 ng/g, respectively. Based on these PCB determinations for the ovaries and somatic tissue, we concluded that release of eggs by females at previous spawnings was not a contributing factor to the observed difference in PCB concentrations between the sexes. Bioenergetics modeling results indicated that the growth dilution effect could explain males being higher than females in PCB concentration by only 3-7%. We concluded that the higher PCB concentration in males was most likely due to higher rate of energy expenditure, originating from greater activity and a higher resting metabolic rate. Mean PCB concentration in the cisco eggs was well below the U. S. Food and Drug Administration and Ontario Ministry of Environment guidelines of 2000 and 844 ng/g, respectively, and this finding may have implications for the cisco roe fishery currently operating in Lake Superior. Published by Elsevier B.V.

Male preventive health behaviors: perceptions from men, women, and clinical staff along the U.S. Mexico border.

Science.gov (United States)

Hunter, Jennifer B; Fernandez, Maria Lourdes; Lacy-Martinez, Charles R; Dunne-Sosa, Andrea M; Coe, M Kathryn

2007-12-01

Mexican American males have higher levels of total cholesterol and triglycerides, higher body mass indexes, and a higher prevalence of diabetes than do non-Hispanic White males. They are the least likely Hispanic subgroup to be insured, to have recently visited a physician, or to have preventive exams. To explore factors related to the use of preventive exams among mature men, and specifically among Mexican American men residing along the Arizona, United States/Sonora, Mexico border, information on barriers and motivating factors to male participation in preventive screening exams was collected. Interviews were conducted with mature men and women from a single border community and with clinical staff from three different border communities who deliver services to similar populations. Responses were triangulated. Common themes identified include health education/information/advertisement and female/family support as motivating factors and machismo/denial/fatalism as a barrier to male health-seeking behavior.

Females have stronger neurogenic response than males after non-specific nasal challenge in patients with seasonal allergic rhinitis.

Science.gov (United States)

Tomljenovic, Dejan; Baudoin, Tomislav; Megla, Zeljka Bukovec; Geber, Goran; Scadding, Glenis; Kalogjera, Livije

2018-07-01

Epidemiological studies show female predominance in the prevalence of non- allergic rhinitis (NAR) and local allergic rhinitis (LAR). Experimental studies show female patients with allergic rhinitis (AR) demonstrate higher levels of sensitivity to irritants and airway hyperresponsiveness than males. Bronchial asthma shows female predominance in post-puberty patients, and gender interaction with severe asthma endotypes. Fibromyalgia, chronic fatigue syndrome, migraine and chronic cough, syndromes, which are commonly related to neurokinin substance P (SP) in the literature, also show strong female predominance. Studies have demonstrated that sex hormones, primarily oestrogens, affect mast cell activation. Mast cell proteases can amplify neurogenic inflammatory responses including the release of SP. Based on human epidemiological data and animal experimental data we hypothesized that female patients have different interaction between mast cell activation and neurogenic inflammation, i.e. substance P release, resulting in a different nasal symptom profile. To test the hypothesis we performed allergen and non-specific nasal challenges in patients with seasonal allergic rhinitis (SAR) out of season and looked for gender differences in subjective and objective responses. The interaction between subjective and objective reactivity was evaluated through the comparison of subjective symptom scores, concentrations of neurokinin substance P (SP) and cellular markers in nasal lavages after low doses of nasal allergen challenges. Female allergic subjects tended to have higher substance P (SP) concentrations both before and after non-specific challenges. The difference between post-allergen and post - hypertonic saline (HTS) challenge was highly significant in female patients (p = 0.001), while insignificant in male subjects (p = 0.14). Female patients had significantly stronger burning sensation after HTS challenge than male. These data indicate difference in the

Male sexuality.

Science.gov (United States)

Ginsberg, Terrie B

2010-05-01

It should be recognized that sexuality in the aging male is of such import that a complete sexual history must be performed. By taking a complete sexual history, facts can be obtained that will allow for appropriate focus relating to a holistic evaluation and will enable us to dispel antiquated sexual myths pertaining to the aging male. If initiated by the history taker, questions concerning sexuality may be discussed more comfortably by the patient. Erectile dysfunction, male sexual response cycle, testosterone, sexually transmitted diseases, human immunodeficiency virus, long-term illness, along with religion and culture are explored in this article with the aim of improving one's knowledge base, self reflection, and awareness of the importance of male sexuality. A complete understanding and appreciation of the aging male's medical history, surgical history, social history, and emotional history as well as his sexual, cultural, and religious concepts will allow the health care provider to better analyze information, and to recommend and provide appropriate advice and treatment to the aging male patient. Copyright 2010 Elsevier Inc. All rights reserved.

Potential Factors Associated with Contraceptive Intention Among Adolescent Males in Taiwan

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Ruey-Hsia Wang

2004-03-01

Full Text Available This study explored the predictors of contraceptive intention in adolescent males in Taiwan. It used a cross-sectional design and a sample of 1,000 vocational high school male students to determine the potential factors associated with contraceptive intention. Data were collected on an anonymous, self-administered questionnaire, including personal background variables, prior sexual experience, contraceptive knowledge, contraceptive attitude, contraceptive self-efficacy, perception of peers' contraceptive behavior, perception of support from significant others, and parental-adolescent communication about contraception. A total of 230 participants (23% had prior sexual experience, 13% (30 of whom reported being involved in their girlfriends' pregnancies. Of the participants, 45% recognized the use of condoms as the most favorable contraceptive method for future sexual intercourse. Second to condom use, the combination of the calendar method and condom use was also popular (13.1%. Multiple stepwise regression indicated that better contraceptive attitudes, higher contraceptive self-efficacy, no prior sexual experience, more perception of peers' contraceptive behavior, and higher perception of support from significant others were predictors of higher contraceptive intention. The above predicting factors explained 31.9% of the total variance for contraceptive intention among adolescents. These results provide health professionals with important information to understand the reality adolescents encounter and to design effective contraceptive programs for male adolescents.

Risk factors for HIV infection in Males who have Sex with Males (MSM in Bangladesh

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Khan Omar A

2007-07-01

Full Text Available Abstract Background Recent surveillance data from Bangladesh indicate rising HIV infection among intravenous drug users (IDU in the country. We suggest a likely association between HIV risk factors in this group and other groups, such as males who have sex with males (MSM. Methods Data on MSM in Bangladesh was collected and analyzed from numerous primary and secondary sources, including government ministries, non-profit health organizations, and personal communications. Results The overall prevalence of HIV in Bangladesh is relatively low, but surveillance data indicate that infection has reached significant proportions in certain high-risk groups and may soon spread to other groups, specifically MSM. Conclusion The epidemiology of HIV infection in other countries suggests that increasing rates of HIV in higher-risk populations can precede an epidemic in the general population. We review the data concerning MSM, IDU and HIV in Bangladesh from a variety of sources and propose ways to prevent HIV transmission.

Differences in peripheral sensory input to the olfactory bulb between male and female mice

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Kass, Marley D.; Czarnecki, Lindsey A.; Moberly, Andrew H.; McGann, John P.

2017-04-01

Female mammals generally have a superior sense of smell than males, but the biological basis of this difference is unknown. Here, we demonstrate sexually dimorphic neural coding of odorants by olfactory sensory neurons (OSNs), primary sensory neurons that physically contact odor molecules in the nose and provide the initial sensory input to the brain’s olfactory bulb. We performed in vivo optical neurophysiology to visualize odorant-evoked OSN synaptic output into olfactory bub glomeruli in unmanipulated (gonad-intact) adult mice from both sexes, and found that in females odorant presentation evoked more rapid OSN signaling over a broader range of OSNs than in males. These spatiotemporal differences enhanced the contrast between the neural representations of chemically related odorants in females compared to males during stimulus presentation. Removing circulating sex hormones makes these signals slower and less discriminable in females, while in males they become faster and more discriminable, suggesting opposite roles for gonadal hormones in influencing male and female olfactory function. These results demonstrate that the famous sex difference in olfactory abilities likely originates in the primary sensory neurons, and suggest that hormonal modulation of the peripheral olfactory system could underlie differences in how males and females experience the olfactory world.

Prevalence and Risk Factors for Self-Reported Violence of Osaka and Seattle Male Youths

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Bui, Laura; Farrington, David P.; Ueda, Mitsuaki; Hill, Karl G.

2013-01-01

Traditionally, Japan has been regarded as a country with low crime. Comparative research has given insights into the extent of similarities and differences in crime between America and Japan. The importance of these studies is the examination of whether Western-established criminological knowledge is applicable to non- Western societies like Japan. Unfortunately, comparative self-report studies involving Japan and investigating youth offending are scarce. The current study investigates risk factors and self-reports of violence from Osaka and Seattle male youths. The findings reveal that Japanese male youths self-report a higher prevalence of violence than Seattle male youths. Risk factors for violence, issues of comparability, and prevalence versus strength of relationships of risk factors are examined. It is concluded that the higher prevalence of violence in Osaka is primarily a function of the higher prevalence of troubled peers and risk taking. The findings call for replication of this type of comparative research. PMID:24013769

GnRH mRNA levels in male three-spined sticklebacks, Gasterosteus aculeatus, under different reproductive conditions.

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Shao, Yi Ta; Tseng, Yung Che; Chang, Chia-Hao; Yan, Hong Young; Hwang, Pung Pung; Borg, Bertil

2015-02-01

In vertebrates, reproduction is regulated by the brain-pituitary-gonad (BPG) axis, where the gonadotropin-releasing hormone (GnRH) is one of the key components. However, very little is known about the possible role of GnRH in the environmental and feedback control of fish reproduction. To investigate this, full-length gnrh2 (chicken GnRH II) and gnrh3 (salmon GnRH) sequences of male three-spined sticklebacks (Gasterosteus aculeatus), which are clustered with the taxa of the same GnRH type as other Euteleostei, were cloned and annotated. gnrh1 is absent in this species. The mRNA levels of gnrh2 and gnrh3 in the sticklebacks' brain were measured under breeding and post-breeding conditions as well as in castrated and sham-operated breeding fish and castrated/sham-operated fish kept under long-day (LD 16:8) and short-day (LD 8:16) conditions. Fully breeding males had considerably higher mRNA levels of gnrh2 and gnrh3 in the thalamus (Th) and in the telencephalon and preoptic area (T+POA), respectively, than post-breeding males. Sham-operated breeding males have higher gnrh3 mRNA levels than the corresponding castrated males. Moreover, higher gnrh2 mRNA levels in the Th and higher gnrh3 mRNA levels in the T+POA and hypothalamus (HypTh) were also found in long-day sham-operated males than in sham-operated fish kept under an inhibitory short day photoperiod. Nevertheless, gnrh2 and gnrh3 mRNA levels were not up-regulated in castrated males kept under long-day photoperiod, which suggests that positive feedbacks on the brain-pituitary-gonad axis are necessary for this response. Copyright © 2014 Elsevier Inc. All rights reserved.

The study of serum markers of immunological remission in male hyperthyroidism patients after treatment

International Nuclear Information System (INIS)

Song Qingzhang; Zhang Aihua; Bai Zhenlian; Zhuo Liankun; Wang Hong

2005-01-01

To study the cause for slow recovery in male hyperthyroidism patients after treated with ATD, the changes of serum β 2 -MG, TGAb and TMAb were measured by RIA. A total of 164 male hyperthyoidism patients were divided into 3 groups by their different therapeutic effects: untreated patients (group B, n=65), treated but unrelieved patients (group C, n=52), treated and recovered patients (group D, n=47) and 58 normal persons serving as controls (group A). The results indicated that the levels of serum β 2 -MG, FT 3 and FT 4 were significantly higher in group B and C than those in group A (P 3 or FT 4 and β 2 -MG respectively in group B and C. There was no significant difference in β 2 -MG, FT 3 and FT 4 between group D and A (P>0.05). And there was no difference in the positive rates of TGAb and TMAb between group D and C(P>0.05). The serum β 2 -MG was still higher in 19.1% patients and the positive rates of TGAb and TMAb were also higher in 23.4% patients. These results suggest that β 2 -MG, TGAb and TMAb could act as serum markers of immunological remission for male hyperthyroidism patients and the determination of β 2 -MG, TGAb and TMAb could be benifical to monitoring therapeutic effect. The cause for slow recovery in about 20% male hyperthyroidism patients might be due to higher serum β 2 -MG and higher positive rates of TGAb and TMAb. (authors)

Reproductive traits in captive and free-ranging males of the critically endangered Iberian lynx (Lynx pardinus).

Science.gov (United States)

Gañán, Natalia; Sestelo, Adrián; Garde, J Julián; Martínez, Fernando; Vargas, Astrid; Sánchez, Iñigo; Pérez-Aspa, María José; López-Bao, José Vicente; Palomares, Francisco; Gomendio, Montserrat; Roldan, Eduardo R S

2010-01-01

The Iberian lynx (Lynx pardinus) is the most endangered felid in the world. Adequate genetic management of in situ and ex situ populations, and linkage between both, require knowledge on male reproductive biology and factors influencing it. We examined the influence of age, free-ranging versus captive conditions and seasonality on phenotypic, endocrine and semen traits, and links between reproductive traits and male fertility. Males had relatively small testes, produced low sperm numbers, a low proportion of normal sperm, and a high proportion of motile sperm. Young (2-year-old) males had lower testosterone levels, fewer sperm, and a lower proportion of motile and normal sperm than > or =4-year-old males. No major differences were found in semen traits before and after the mating season or between free-ranging and captive males, although the latter had better sperm motility. Males with larger relative testes weight and more sperm copulated more frequently, whereas males that produced more sperm with higher motility produced more cubs per female. In conclusion, small relative testes size and low sperm quality could indicate either low levels of sperm competition or high levels of inbreeding. Young males are probably subfertile; there is a slight trend for males in the captive breeding programme to have better semen quality than wild males, and males with higher sperm production are sexually more active and more fertile. These findings have major implications for decisions regarding which males should breed, provide samples for the genetic resource bank, or participate in programmes involving the use of assisted reproductive techniques.

Female vs. Male Ampelmännchen-Gender-Specific Reaction Times to Male and Female Traffic Light Figures

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Farid I. Kandil

2017-05-01

Full Text Available Traffic signs are important visual guiding signals for the safe navigation through complex road traffic. Interestingly, there is little variation in the traffic signs for cars around the world. However, remarkable variation exists for pedestrian traffic signs. Following up from an earlier study, we investigated the visual efficacy of female vs. male German Ampelmännchen pedestrian traffic signs. In a Stroop-like test, 30 subjects were presented with female and male go and no-go traffic light figures that were shown either in the corresponding or opposing color. Subjects had to indicate, based either solely on the form or the color of the figure, whether they were allowed to go. Accuracy and response times across all subjects did not differ for the female vs. male signs, indicating that Ampelfrau and Ampelmann signs have equal visual efficacy. However, subjects responded faster to signs of their own vs. the opposite gender. This preference for signs of one's own gender is in accordance with effects in social psychology described by social learning theory. An introduction of such novel traffic lights may, thus, contribute to higher compliance with the traffic sign signals.

Acoustic passaggio pedagogy for the male voice.

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Bozeman, Kenneth Wood

2013-07-01

Awareness of interactions between the lower harmonics of the voice source and the first formant of the vocal tract, and of the passive vowel modifications that accompany them, can assist in working out a smooth transition through the passaggio of the male voice. A stable vocal tract length establishes the general location of all formants, including the higher formants that form the singer's formant cluster. Untrained males instinctively shorten the tube to preserve the strong F1/H2 acoustic coupling of voce aperta, resulting in 'yell' timbre. If tube length and shape are kept stable during pitch ascent, the yell can be avoided by allowing the second harmonic to rise above the first formant, creating the balanced timbre of voce chiusa.

The Evaluation of the Relationship Between Obesity and Male Infertility

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Fikret Erdemir

2013-01-01

Full Text Available   Infertility, defined as the inability to conceive after one year of unprotected intercourse, affects approximately 15% of couples. Male factor infertility is the sole cause of infertility in approximately 20% of infertile couples, with an additional 30% to 40% secondary to both male and female factors. Thus, male factor infertility is present in approximately half of all infertile couples. Known etiologies of male infertility include cryptorchidism, testicular torsion or trauma, varicocele, seminal tract infections, anti-sperm antibodies, hypogonadotropic hypogonadism, gonadal dysgenesis, and obstruction of the reproductive channels. Recently in some studies, it has been reported that increased body mass index negatively affect on male fertility or semen parameters.Overweight and obesity have become a major public health concern worldwide. The prevalence of male obesity or overweight in the united states was reported to be 71%. This ratio changes between 10% and 60% in the world. Negative effects of obesity on male fertility are postulated to occur through several mechanisms. Obese men have been shown to exhibit higher levels of circulating estradiol. Several studies reveal a direct correlation between a rise in BMI and a decline in both free and total blood testosterone levels. In addition, obesity may cause to oxidative stress. All these changes may affect to semen parameters in obese cases. However, the relationship between male obesity and fertility parameters has not been well established. The aim of this review is to evaluate the relationship between the obesity and male infertility.

Differential Effect of Active Smoking on Gene Expression in Male and Female Smokers

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Paul, Sunirmal; Amundson, Sally A

2015-01-01

Smoking is the second leading cause of preventable death in the United States. Cohort epidemiological studies have demonstrated that women are more vulnerable to cigarette-smoking induced diseases than their male counterparts, however, the molecular basis of these differences has remained unknown. In this study, we explored if there were differences in the gene expression patterns between male and female smokers, and how these patterns might reflect different sex-specific responses to the stress of smoking. Using whole genome microarray gene expression profiling, we found that a substantial number of oxidant related genes were expressed in both male and female smokers, however, smoking-responsive genes did indeed differ greatly between male and female smokers. Gene set enrichment analysis (GSEA) against reference oncogenic signature gene sets identified a large number of oncogenic pathway gene-sets that were significantly altered in female smokers compared to male smokers. In addition, functional annotation with Ingenuity Pathway Analysis (IPA) identified smoking-correlated genes associated with biological functions in male and female smokers that are directly relevant to well-known smoking related pathologies. However, these relevant biological functions were strikingly overrepresented in female smokers compared to male smokers. IPA network analysis with the functional categories of immune and inflammatory response gene products suggested potential interactions between smoking response and female hormones. Our results demonstrate a striking dichotomy between male and female gene expression responses to smoking. This is the first genome-wide expression study to compare the sex-specific impacts of smoking at a molecular level and suggests a novel potential connection between sex hormone signaling and smoking-induced diseases in female smokers. PMID:25621181

A unique view on male infertility around the globe.

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Agarwal, Ashok; Mulgund, Aditi; Hamada, Alaa; Chyatte, Michelle Renee

2015-04-26

Infertility affects an estimated 15% of couples globally, amounting to 48.5 million couples. Males are found to be solely responsible for 20-30% of infertility cases and contribute to 50% of cases overall. However, this number does not accurately represent all regions of the world. Indeed, on a global level, there is a lack of accurate statistics on rates of male infertility. Our report examines major regions of the world and reports rates of male infertility based on data on female infertility. Our search consisted of systematic reviews, meta-analyses, and population-based studies by searching the terms "epidemiology, male infertility, and prevalence." We identified 16 articles for detailed study. We typically used the assumption that 50% of all cases of infertility are due to female factors alone, 20-30% are due to male factors alone, and the remaining 20-30% are due to a combination of male and female factors. Therefore, in regions of the world where male factor or rates of male infertility were not reported, we used this assumption to calculate general rates of male factor infertility. Our calculated data showed that the distribution of infertility due to male factor ranged from 20% to 70% and that the percentage of infertile men ranged from 2·5% to 12%. Infertility rates were highest in Africa and Central/Eastern Europe. Additionally, according to a variety of sources, rates of male infertility in North America, Australia, and Central and Eastern Europe varied from 4 5-6%, 9%, and 8-12%, respectively. This study demonstrates a novel and unique way to calculate the distribution of male infertility around the world. According to our results, at least 30 million men worldwide are infertile with the highest rates in Africa and Eastern Europe. Results indicate further research is needed regarding etiology and treatment, reduce stigma & cultural barriers, and establish a more precise calculation.

On the mutagenicity of methadone hydrochloride. Induced dominant lethal mutation and spermatocyte chromosomal aberrations in treated males.

Science.gov (United States)

Badr, F M; Rabouh, S A; Badr, R S

1979-11-01

The mutagenicity of methadone hydrochloride was tested in male mice using the dominant lethal mutation technique and the spermatocyte test of treated mice. Male mice of C3H inbred strain received one of the following doses, 1, 2, 4 or 6 mg/kg body weight once a day for 3 consecutive days. Another group of mice served as control and received saline instead. Treated males were then mated to virgin females at 3-day intervals for a period of 45 days. Pregnant females were dissected at mid-term and the corpora lutea and intrauterine contents were recorded. The spermatocytes of treated males were examined 45-50 d after treatments with methadone and abnormal pairing configurations were scored. The methadone treatment was found to increase the rate of preimplantation deaths consistently in all post-meiotic stages with all doses used. In addition, the higher doses, 4 and 6 mg, affected spermatogonia stages. Quantitatively, the dose-response relationship cannot be demonstrated though the spectrum of effect increased with higher doses as more spermatogenesis stages became more sensitive to the treatment. In many cases the frequency of live implants showed a positive correlation with preimplantation deaths in contrast with the frequency of early deaths which showed only sporadic variation. The mutation indices based on total embryonic death indicate that methadone hydrochloride affected several stages of germ-cell maturation namely, spermatozoa (M.I. 14-35), late spermatids (M.I. 15-48), early spermatids (M.I. 14-50), late spermatocytes (M.I. 15-43) and spermatogonial stages (M.I. 12-63). Chromosome analysis at diakinesis-metaphase 1 revealed significant increase in the frequency of sex chromosome and autosome univalents with different doses of methadone. The smallest dose applied was quite effective and the data represent direct dose-response relationship. Of the multivalent configuration, the most frequent type was chain quadrivalents. The frequencies of total translocations

Are attractive male crickets better able to pay the costs of an immune challenge?

Science.gov (United States)

Telemeco, Melissa S.C.; Bartholomay, Lyric C.

2015-01-01

Reproduction and immunity are fitness-related traits that trade-off with each other. Parasite-mediated theories of sexual selection suggest, however, that higher-quality males should suffer smaller costs to reproduction-related traits and behaviours (e.g., sexual display) from an immune challenge because these males possess more resources with which to deal with the challenge. We used Gryllus texensis field crickets to test the prediction that attractive males should better maintain the performance of fitness-related traits (e.g., calling effort) in the face of an immune challenge compared with unattractive males. We found no support for our original predictions. However, that immune activation causes attractive males to significantly increase their calling effort compared with unattractive males suggests that these males might terminally invest in order to compensate for decreased future reproduction. PMID:26713249

Hormone receptor expression in male breast cancers | Akosa ...

African Journals Online (AJOL)

Male breast cancers are rare but have been found in higher proportions in Black Africans. Prognostic factors for breast cancers include tumour size, grade and stage, and hormone receptor status. The hormone receptor status is an invaluable guide in the use of adjuvant endocrine therapy, but none of the reports available ...

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…

Everywhere you go, everyone is saying condom, condom. But are they being used consistently? Reflections of South African male students about male and female condom use

OpenAIRE

Mantell, Joanne E.; Smit, Jennifer A.; Beksinska, Mags; Scorgie, Fiona; Milford, Cecilia; Balch, Erin; Mabude, Zonke; Smith, Emily; Adams-Skinner, Jessica; Exner, Theresa M.; Hoffman, Susie; Stein, Zena A.

2011-01-01

Young men in South Africa can play a critical role in preventing new human immunodeficiency virus (HIV) infections, yet are seldom targeted for HIV prevention. While reported condom use at last sex has increased considerably among young people, consistent condom use remains a challenge. In this study, 74 male higher education students gave their perspectives on male and female condoms in 10 focus group discussions. All believed that condoms should be used when wanting to prevent conception an...

Radiographic comparison between male and female patients with lumbar spondylolysis.

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Takao, Shoichiro; Sakai, Toshinori; Sairyo, Koichi; Kondo, Tadashi; Ueno, Junji; Yasui, Natsuo; Nishitani, Hiromu

2010-02-01

We studied the lumbar spines of 117 adults (39 women and 78 men) with spondylolysis unrelated to low back pain using multidetector computed tomography (CT). Of the 117 subjects with spondylolysis, including five with multiple-level spondylolysis, there were 124 vertebrae with spondylolysis. In adult lumbar spines with unilateral spondylolysis, there was no significant difference between the incidence of spondylolisthesis in female and male subjects. However, in those with bilateral spondylolysis, there was a significantly higher incidence of spondylolisthesis in female subjects (90.9%) than in males (66.2%). Furthermore, females with bilateral spondylolysis had significant more slippage than males. Lumbar index and lumbar lordosis were not significantly different between male and female subjects, and did not significantly correlate with slippage. In conclusion, to treat acute spondylolysis in adolescents, it is important to obtain bony union at least unilaterally, especially in female subjects, to prevent further slippage.

Dietary isoflavones alter regulatory behaviors, metabolic hormones and neuroendocrine function in Long-Evans male rats

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Bu Lihong

2004-12-01

Full Text Available Abstract Background Phytoestrogens derived from soy foods (or isoflavones have received prevalent usage due to their 'health benefits' of decreasing: a age-related diseases, b hormone-dependent cancers and c postmenopausal symptoms. However, little is known about the influence of dietary phytoestrogens on regulatory behaviors, such as food and water intake, metabolic hormones and neuroendocrine parameters. This study examined important hormonal and metabolic health issues by testing the hypotheses that dietary soy-derived isoflavones influence: 1 body weight and adipose deposition, 2 food and water intake, 3 metabolic hormones (i.e., leptin, insulin, T3 and glucose levels, 4 brain neuropeptide Y (NPY levels, 5 heat production [in brown adipose tissue (BAT quantifying uncoupling protein (UCP-1 mRNA levels] and 6 core body temperature. Methods This was accomplished by conducting longitudinal studies where male Long-Evans rats were exposed (from conception to time of testing or tissue collection to a diet rich in isoflavones (at 600 micrograms/gram of diet or 600 ppm vs. a diet low in isoflavones (at approximately 10–15 micrograms/gram of diet or 10–15 ppm. Body, white adipose tissue and food intake were measured in grams and water intake in milliliters. The hormones (leptin, insulin, T3, glucose and NPY were quantified by radioimmunoassays (RIA. BAT UCP-1 mRNA levels were quantified by PCR and polyacrylamide gel electrophoresis while core body temperatures were recorded by radio telemetry. The data were tested by analysis of variance (ANOVA (or where appropriate by repeated measures. Results Body and adipose tissue weights were decreased in Phyto-600 vs. Phyto-free fed rats. Food and water intake was greater in Phyto-600 animals, that displayed higher hypothalamic (NPY concentrations, but lower plasma leptin and insulin levels, vs. Phyto-free fed males. Higher thyroid levels (and a tendency for higher glucose levels and increased uncoupling

Patterns of male parentage in the fungus-growing ants

DEFF Research Database (Denmark)

Villesen, Palle; Boomsma, JJ

2003-01-01

Ant queens from eight species, covering three genera of lower and two genera of higher attine ants, have exclusively or predominantly single mating. The ensuing full-sib colonies thus have a strong potential reproductive conflict between the queen and the workers over male production...

Urokinase-type plasminogen activator: a new target for male contraception?

Science.gov (United States)

Qin, Ying; Han, Yan; Xiong, Cheng-Liang; Li, Hong-Gang; Hu, Lian; Zhang, Ling

2015-01-01

Urokinase-type plasminogen activator (uPA) is closely related to male reproduction. With the aim of investigating the possibility for uPA as a potential contraceptive target, in the present work, Kunming male mice were immunized by human uPA subcutaneous injection at three separate doses for 3 times. Then the potency of the anti-human uPA antibody in serum was analyzed, and mouse fertility was evaluated. Serum antibody titers for human uPA in immunized groups all reached 1:10,240 or higher levels by enzyme linked immunosorbent assay, and mating experiments revealed that pregnancy rates and the mean number of embryos implanted after mating declined obviously (P male mice. Sperm function tests suggested that the sperm concentration, sperm viability, sperm motility, and in vitro fertilization rate for the cauda epididymis sperm in uPA-immunized groups were lower than those in the controls (P male mice could effectively reduce their fertility, and uPA could become a new target for immunocontraception in male contraceptive development.

Responses of female rock lizards to multiple scent marks of males: effects of male age, male density and scent over-marking.

Science.gov (United States)

Martín, José; López, Pilar

2013-03-01

Scent-marked substrates may inform conspecifics on the characteristics of territorial males. Scent-marks of male Carpetan rock lizards (Iberolacerta cyreni) affect space use of females, which by selecting an area may increase the probability of mating with the male that has scent-marked that area. However, males do not hold exclusive territories, and scent-marks of different individual males are often together. This may provide complex information from multiple sources on the social structure. Here, we examined female preference in response to scent marks of various males and combinations in a laboratory experiment. Females preferred areas scent-marked by territorial old males against those scent-marked by young satellite-sneaker males. This reflected the known preference of females for mating with old males. In a second experiment, females preferred areas scent-marked by two males to areas of similar size marked by a single male. This may increase the probability of obtaining multiple copulations with different males, which may favour sperm competition and cryptic female choice, or may be a way to avoid infertile males. Finally, when we experimentally over-marked the scent-marks of an old male with scent-marks of a young male, females did not avoid, nor prefer, the over-marked area, suggesting that the quality of the old male may override the presence of a satellite male. We suggest that, irrespective of the causes underlying why a female selects a scent-marked area, this strategy may affect her reproductive success, which may have the same evolutionary consequences that "direct" mate choice decisions of other animals. Copyright © 2013 Elsevier B.V. All rights reserved.

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

Science.gov (United States)

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.

CONSIDERATIONS REGARDING ROMANIAN HIGHER EDUCATION GRADUATES

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Popovici (Barbulescu Adina

2012-07-01

Full Text Available The paper aims at analyzing the dynamics of in Romanian higher education graduates in the 2006-2010 period, both in Romania and by the Romanian development regions. After highlighting the importance of human capital and its education, the paper analyzes the dynamics of Romanian higher education graduates in the targeted period, at both of the above-mentioned levels. The conclusions reveal that, during the analysed period: 2006-2010, the number of female, and, respectively, male higher education graduates, as well as the total number of higher education graduates, continuously increased in the 2006-2010 period at the whole country level and registered an increase trend, as well, by the eight development regions of Romania in the 2006-2010 period, with very few exceptions in some years of the period, in some of the the eight development regions of Romania. Therefore, the Romanian higher education system must correlate the graduates number with the number of work places in the Romanian economy, and take into account the necessities imposed by the participation at international competition.

Expansion and access to higher education: how is gender equality

Directory of Open Access Journals (Sweden)

Edineide Jezine

2016-12-01

Full Text Available This article is problematic the process of expansion of higher education in Brazil and the challenges of access and retention of students in vulnerable situations. In this objective set to analyze the gender equality concepts in higher education policies; and enrollment in public and private sectors as they are distributed, considering the gender variable. This is a qualitative study supported by quantitative data of expanding the number of courses and enrollment, considering the Census of Higher Education (2013 that the tip 10 courses with the highest number of female and male enrollment. Based on these data analysis seeks apprehension-der the dynamics at the Federal University of Paraíba (UFPB from the perspective of sexualization / gendering. By analyzing access to this type of education of men and women in UFPB, the data show that more women enter and complete higher education courses. However, when analyze distribution by courses, still remains femininity and masculinity certain professional careers. In this sense, the research results show that the process of expansion of higher education is not accompanied by professional motivations that courses historically constitute as male, the case of Engineering, and / or female courses, the case of pedagogy, keeping inequality processes between the sexes in professional careers.

RELATION BETWEEN EMOTIONAL INTELLIGENCE AND REASONING ABILITY OF HIGHER SECONDARY STUDENTS

OpenAIRE

C. Daisy Nambikkai; Dr. A.Veliappan

2017-01-01

The present study aims to find out the relationship between emotional intelligence and reasoning ability of the higher secondary students. Among the population, 724 samples of higher secondary students were selected randomly from Puducherry region. Findings of the study were i) significant difference is found between male and female higher secondary students in their reasoning ability in science on analogical reasoning, classification as reasoning, eclectic reasoning, deductive reasoning and ...

Intimacy and sexual risk behaviour in serodiscordant male couples.

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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.

Visual perceptions of male obesity: a cross-cultural study examining male and female lay perceptions of obesity in Caucasian males.

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Robinson, Eric; Hogenkamp, Pleunie S

2015-05-16

Obesity is now common and this may have altered visual perceptions of what constitutes a 'normal' and therefore healthy weight. The present study examined cross-cultural differences in male and female participants' ability to visually identify the weight status of photographed Caucasian males. Five hundred and fifty three male and female young adults from the US (high obesity prevalence), UK and Sweden (lower obesity prevalence) participated in an online study. Participants judged the weight status of a series of photographed healthy weight, overweight and obese (class I) Caucasian males and rated the extent to which they believed each male should consider losing weight. There was a strong tendency for both male and female participants to underestimate the weight status of the photographed overweight and obese males. Photographed males were frequently perceived as being of healthier weight than they actually were. Some modest cross-cultural differences were also observed; US participants were worse at recognising obesity than UK participants (p cross-cultural differences were observed for perceptions or attitudes towards the photographed healthy weight or overweight males. The weight status of overweight and obese (class I) Caucasian males is underestimated when judged by males and females using visual information alone. This study provides initial evidence of modest cross-cultural differences in attitudes toward, and the ability to recognise, obesity in Caucasian males.

Calling Out the Elephant: An Examination of African American Male Achievement in Community Colleges

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Edward C. Bush

2010-03-01

Full Text Available This mixed method study examines the effects of community college institutional factors on the academic achievement of African American males and their perceptions of their college experience. We found that African American men in comparison to other ethnic and gender sub-groups (for both the California community college system and at Inland Community College are disproportionately underachieving in all segments of the academic outcomes measured. African American men throughout California’s community college system (including Inland Community College are the lowest performing subgroup when one considers: percentage of degrees earned, persistence rates, and average cumulative grade point average. The analysis of African American men’s perceptions of their college experience suggest that African American men have greater amounts of dissatisfaction and do not engage with the various segments of the college when compared to the other subgroups in the study. African American males were more likely not to meet with faculty members or have contact with them outside of the classroom. More importantly, faculty interaction predicted if African American male students persisted, transferred, and maintained a higher grade point average at the case study institution. The variables associated with campus climate predicted if African American male students transferred, had higher grade point averages, and graduated at higher rates from the case institution.

Endoscopic forehead lift in patients with male pattern baldness.

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Shipchandler, Taha Z; Sultan, Babar; Byrne, Patrick J

2012-01-01

The presence of male pattern baldness poses a significant challenge when attempting to optimize treatment of the upper third of the face. The purpose of this study is to demonstrate and discuss results of the endoscopic forehead lift in patients with male pattern baldness. This was a retrospective case series done in an academic medical center. Eleven patients with male pattern baldness (Norwood class IV-VII) underwent endoscopic forehead lift for forehead creases and brow ptosis. All patients achieved smoothing of the forehead and elevation of the brow with no scalp anesthesia at 1 month postoperatively. All patients were pleased with the healing of their incisions in midline, paramedian, and temporal regions. Alloplastic fixation devices used were visible postoperatively in 2 patients initially. The endoscopic forehead lift is a suitable approach for treating the upper third of the face in the presence of male pattern baldness. The use of alloplastic fixation devices may be used in this patient population, but other fixation methods should be considered. Copyright © 2012 Elsevier Inc. All rights reserved.

Females With a Mutation in a Nuclear-Encoded Mitochondrial Protein Pay a Higher Cost of Survival Than Do Males in Drosophila

OpenAIRE

Melvin, Richard G.; Ballard, J. William O.

2011-01-01

Males and females age at different rates in a variety of species, but the mechanisms underlying the difference is not understood. In this study, we investigated sex-specific costs of a naturally occurring mildly deleterious deletion (DTrp85, DVal86) in cytochrome c oxidase subunit 7A (cox7A) in Drosophila simulans. We observed that females and males homozygous for the mutation had 30% and 26% reduced Cox activity, respectively, compared with wild type. Furthermore, 4-day-old females had 34%–4...

Genetic analysis of male reproductive success in relation to density in the zebrafish, Danio rerio

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Jordan William C

2006-04-01

Full Text Available Abstract Background We used behavioural and genetic data to investigate the effects of density on male reproductive success in the zebrafish, Danio rerio. Based on previous measurements of aggression and courtship behaviour by territorial males, we predicted that they would sire more offspring than non-territorial males. Results Microsatellite analysis of paternity showed that at low densities territorial males had higher reproductive success than non-territorial males. However, at high density territorial males were no more successful than non-territorials and the sex difference in the opportunity for sexual selection, based on the parameter Imates, was low. Conclusion Male zebrafish exhibit two distinct mating tactics; territoriality and active pursuit of females. Male reproductive success is density dependent and the opportunity for sexual selection appears to be weak in this species.

Development of the rate of employment and unemployment of males and females in countries of EU15

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Milan Palát

2005-01-01

Full Text Available The paper is focused on the evaluation the rates of employment and unemployment of women, men and as a whole in countries of EU15. Rates of employment were evaluated in the period 1993–2002. Rates of unemployment were evaluated in the period 1994–2003. Employment of males in fifteen countries of EU is higher then employment of females. Unemployment of females in fifteen countries of EU is higher than unemployment of males and in opposite unemployment of females in Sweden is lower than unemployment of males. Trends of rates of male, female and total employment and unemployment are evaluated. Methods of regression and correlation analysis, development trends and cluster analysis were applied for the mathematical-statistical analysis.

Effects of a selectively bred novelty-seeking phenotype on the motivation to take cocaine in male and female rats

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Cummings Jennifer A

2011-03-01

Full Text Available Abstract Background Gender and enhanced novelty reactivity can predispose certain individuals to drug abuse. Previous research in male and female rats selectively bred for high or low locomotor reactivity to novelty found that bred High Responders (bHRs acquire cocaine self-administration more rapidly than bred Low Responders (bLRs and that bHR females in particular self-administered more cocaine than the other groups. The experiments presented here aimed to determine whether an individual's sex and behavioral phenotype interact to affect motivation to take cocaine. Methods We examined motivation for taking cocaine in two experiments using a range of doses on a progressive ratio (PR schedule of responding in bHR or bLR males and females. Additionally, we included a measure of continuing to respond in the absence of reinforcement, a feature of addiction that has been recently incorporated into tests of animal models on the basis of the criteria for substance use disorder in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. Statistical analyses were performed using PASW Statistics 18.0 software. Data were analyzed using repeated-measures analysis of variance followed by a Bonferroni correction post hoc test when applicable. Results We found sex differences as well as effects of novelty reactivity on the motivation to self-administer cocaine. Specifically, females demonstrated higher breaking points on the PR schedule compared with males, regardless of phenotype, and bHR males and females exhibited higher motivation than bLR animals at a number of the doses studied. Conclusions An individual's sex continues to be a predisposing factor with respect to drug abuse liability and can be compounded by additional individual differences such as reactivity to novelty.

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.

Mutation of Drosophila dopamine receptor DopR leads to male-male courtship behavior.

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Chen, Bin; Liu, He; Ren, Jing; Guo, Aike

2012-07-06

In Drosophila, dopamine plays important roles in many biological processes as a neuromodulator. Previous studies showed that dopamine level could affect fly courtship behaviors. Disturbed dopamine level leads to abnormal courtship behavior in two different ways. Dopamine up-regulation induces male-male courtship behavior, while down-regulation of dopamine level results in increased sexual attractiveness of males towards other male flies. Until now, the identity of the dopamine receptor involved in this abnormal male-male courtship behavior remains unknown. Here we used genetic approaches to investigate the role of dopamine receptors in fly courtship behavior. We found that a dopamine D1-like receptor, DopR, was involved in fly courtship behavior. DopR mutant male flies display male-male courtship behavior. This behavior is mainly due to the male's increased propensity to court other males. Expression of functional DopR successfully rescued this mutant phenotype. Knock-down of D2-like receptor D2R and another D1-like receptor, DAMB, did not induce male-male courtship behavior, indicating the receptor-type specificity of this phenomenon. Our findings provide insight into a possible link between dopamine level disturbance and the induced male-male courtship behavior. Copyright © 2012 Elsevier Inc. All rights reserved.

Bill redness is positively associated with reproduction and survival in male and female zebra finches.

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Mirre J P Simons

Full Text Available Sexual traits can serve as honest indicators of phenotypic quality when they are costly. Brightly coloured yellow to red traits, which are pigmented by carotenoids, are relatively common in birds, and feature in sexual selection. Carotenoids have been linked to immune and antioxidant function, and the trade-off between ornamentation and these physiological functions provides a potential mechanism rendering carotenoid based signals costly. Mutual ornamentation is also common in birds and can be maintained by mutual mate choice for this ornament or by a correlated response in one sex to selection on the other sex. When selection pressures differ between the sexes this can cause intralocus sexual conflict. Sexually antagonistic selection pressures have been demonstrated for few sexual traits, and for carotenoid-dependent traits there is a single example: bill redness was found to be positively associated with survival and reproductive output in male zebra finches, but negatively so in females. We retested these associations in our captive zebra finch population without two possible limitations of this earlier study. Contrary to the earlier findings, we found no evidence for sexually antagonistic selection. In both sexes, individuals with redder bills showed higher survival. This association disappeared among the females with the reddest bills. Furthermore, females with redder bills achieved higher reproductive output. We conclude that bill redness of male and female zebra finches honestly signals phenotypic quality, and discuss the possible causes of the differences between our results and earlier findings.

Genital sores - male

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Sores - male genitals; Ulcers - male genitals ... A common cause of male genital sores are infections that are spread through sexual contact, such as: Genital herpes (small, painful blisters filled with clear ...

Female harbor seal (Phoca vitulina) behavioral response to playbacks of underwater male acoustic advertisement displays.

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Matthews, Leanna P; Blades, Brittany; Parks, Susan E

2018-01-01

During the breeding season, male harbor seals ( Phoca vitulina ) make underwater acoustic displays using vocalizations known as roars. These roars have been shown to function in territory establishment in some breeding areas and have been hypothesized to be important for female choice, but the function of these sounds remains unresolved. This study consisted of a series of playback experiments in which captive female harbor seals were exposed to recordings of male roars to determine if females respond to recordings of male vocalizations and whether or not they respond differently to roars from categories with different acoustic characteristics. The categories included roars with characteristics of dominant males (longest duration, lowest frequency), subordinate males (shortest duration, highest frequency), combinations of call parameters from dominant and subordinate males (long duration, high frequency and short duration, low frequency), and control playbacks of water noise and water noise with tonal signals in the same frequency range as male signals. Results indicate that overall females have a significantly higher level of response to playbacks that imitate male vocalizations when compared to control playbacks of water noise. Specifically, there was a higher level of response to playbacks representing dominant male vocalization when compared to the control playbacks. For most individuals, there was a greater response to playbacks representing dominant male vocalizations compared to playbacks representing subordinate male vocalizations; however, there was no statistical difference between those two playback types. Additionally, there was no difference between the playbacks of call parameter combinations and the controls. Investigating female preference for male harbor seal vocalizations is a critical step in understanding the harbor seal mating system and further studies expanding on this captive study will help shed light on this important issue.

Drug- and cue-induced reinstatement of cannabinoid-seeking behaviour in male and female rats: influence of ovarian hormones.

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Fattore, L; Spano, M S; Altea, S; Fadda, P; Fratta, W

2010-06-01

Animal and human studies have shown that sex and hormones are key factors in modulating addiction. Previously, we have demonstrated that self-administration of the cannabinoid CB(1) receptor agonist WIN55,212-2 (WIN; 12.5 microg.kg(-1) per infusion) is dependent on sex, intact female rats being more sensitive than males to the reinforcing properties of cannabinoids, and on the oestrous cycle, ovariectomized (OVX) females being less responsive than intact females. This follow-up study investigated whether sex and ovarian function also affect reinstatement of cannabinoid-seeking in rats after exposure to drug or cue priming. After priming with 0.15 or 0.3 mg.kg(-1) WIN, intact female rats exhibited stronger reinstatement than males and OVX females. Responses of intact female rats were higher than those of male and OVX rats even after priming with a drug-associated visual (Light) or auditory (Tone) cue, or a WIN + Light combination. However, latency to the first response did not differ between intact and OVX female rats, and males showed the longest latency to initiate lever-pressing activity. Our study provides compelling evidence for a pivotal role of sex and the oestrous cycle in modulating cannabinoid-seeking, with ovariectomy diminishing drug and cue-induced reinstatement. However, it is possible that sex differences during self-administration training are responsible for sex differences in reinstatement. Finding that not only drug primings but also acute exposure to drug-associated cues can reinstate responding in rats could have significant implications for the development of pharmacological and behavioural treatments of abstinent female and male marijuana smokers.

Self-ratings of physical attractiveness in a competitive context: when males are more sensitive to self-perceptions than females.

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Saad, Gad; Gill, Tripat

2009-10-01

The authors investigated sex differences in the ratings of physical attractiveness in a competitive context. Participants in an Ultimatum Game experiment offered to split a sum of money with their opponents who could either accept or reject the offers; subsequently, physical attractiveness ratings (both self-ratings and of the other) were obtained. The authors found that male participants rated themselves higher on physical attractiveness when facing male opponents than when facing female ones; there was no such difference for the female participants. Furthermore, male participants' self-ratings of physical attractiveness were higher than the ratings provided by their corresponding male opponents. The authors discuss these findings using the tenets of evolutionary psychology pertaining to as male intra-sexual rivalry in competitive contexts.

Coffee consumption and periodontal disease in males.

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Ng, Nathan; Kaye, Elizabeth Krall; Garcia, Raul I

2014-08-01

Coffee is a major dietary source of antioxidants as well as of other anti-inflammatory factors. Given the beneficial role of such factors in periodontal disease, whether coffee intake is associated with periodontal disease in adult males was explored. Existing data collected by a prospective, closed-panel cohort study of aging and oral health in adult males was used. Participants included the 1,152 dentate males in the Veterans Affairs (VA) Dental Longitudinal Study who presented for comprehensive medical and dental examinations from 1968 to 1998. Mean age at baseline was 48 years; males were followed for up to 30 years. Participants are not VA patients; rather, they receive their medical and dental care in the private sector. Periodontal status was assessed by probing depth (PD), bleeding on probing, and radiographic alveolar bone loss (ABL), measured on intraoral periapical radiographs with a modified Schei ruler method. Moderate-to-severe periodontal disease was defined as cumulative numbers of teeth exhibiting PD ≥4 mm or ABL ≥40%. Coffee intake was obtained from participant self-reports using the Cornell Medical Index and food frequency questionnaires. Multivariate repeated-measures generalized linear models estimated mean number of teeth with moderate-to-severe disease at each examination by coffee intake level. It was found that higher coffee consumption was associated with a small but significant reduction in number of teeth with periodontal bone loss. No evidence was found that coffee consumption was harmful to periodontal health. Coffee consumption may be protective against periodontal bone loss in adult males.

Induced mutant for male sterility in niger

International Nuclear Information System (INIS)

Sujatha, M.

2001-01-01

Full text: Niger (Guizotia abyssinica Cass.), an important oilseed crop of the family Compositae is highly cross-pollinated due to the twin mechanisms of protandry and incompatibility. Studies revealed the functional nature of protandry and the breakdown of incompatibility with alteration in temperature. It has very small flowers (disc florets) arranged in a capitulum that open on 3-4 consecutive days which pose problems in emasculation for cross-breeding. To induce mutations, seeds of variety 'IGP-76' were irradiated with γ-rays 200 to 1000 Gy. All seeds of M 1 plants were sown separately in individual plant-to progeny rows. The results of screening of M 2 segregating material indicated that γ-ray treatment was effective in induction of male sterility. Frequency of visible mutations were higher in sibbed progeny as compared to open pollinated population and male sterile plants were observed only in sibbed population (1000 Gy). Male sterile plants could easily be identified at the flowering stage by their altered floral morphology (disc florets transformed into ligulate ray florets) and complete absence or presence of a rudimentary anther column. Seeds were collected following sib-mating with the fertile counterparts. Progeny segregated in a ration of 3 normal : 1 male sterile. Further work on the mechanism of sterility, maintenance and linkage relationships with associated characters is under progress. This is the first report of induction of male sterility in niger through the use of physical mutagens. The availability of this mutant will be of great value for exploitation of heterosis on commercial basis. (author)

Comparison of the course of infection with Giardia muris in male and female mice.

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Daniels, C W; Belosevic, M

1995-01-01

The infection with Giardia muris in male and female C57BL/6 mice was characterized by enumerating cyst release in the feces and trophozoite burden in the small intestine. Cyst release differed between males and females during the course of the primary and challenge infections. Males and females released similar numbers of cysts in the feces during the acute phase of the infection. However, the trophozoite burden was significantly higher in males during the same period. Males released cysts in their feces longer than females and trophozoites present in their intestines for a longer period than females. From day 18 of infection the females did not release cysts in their feces, while males continued to do so for at least 60 days. Thus, distinct differences exist between male and female mice in their ability to harbor and eliminate this intestinal parasite.

Are attractive male crickets better able to pay the costs of an immune challenge?

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Clint D. Kelly

2015-12-01

Full Text Available Reproduction and immunity are fitness-related traits that trade-off with each other. Parasite-mediated theories of sexual selection suggest, however, that higher-quality males should suffer smaller costs to reproduction-related traits and behaviours (e.g., sexual display from an immune challenge because these males possess more resources with which to deal with the challenge. We used Gryllus texensis field crickets to test the prediction that attractive males should better maintain the performance of fitness-related traits (e.g., calling effort in the face of an immune challenge compared with unattractive males. We found no support for our original predictions. However, that immune activation causes attractive males to significantly increase their calling effort compared with unattractive males suggests that these males might terminally invest in order to compensate for decreased future reproduction.

Male pattern baldness

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Alopecia in men; Baldness - male; Hair loss in men; Androgenetic alopecia ... Male pattern baldness is related to your genes and male sex hormones. It usually follows a pattern of receding hairline and ...

Low level of polyandry constrains phenotypic plasticity of male body size in mites.

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Peter Schausberger

Full Text Available Polyandry, i.e. females mating with multiple males, is more common than previously anticipated and potentially provides both direct and indirect fitness benefits to females. The level of polyandry (defined by the lifetime number of male mates of a female is an important determinant of the occurrence and intensity of sexual selection acting on male phenotypes. While the forces of sexual selection acting on phenotypic male traits such as body size are relatively well understood, sexual selection acting on phenotypic plasticity of these traits is unexplored. We tackled this issue by scrutinizing the link between polyandry and phenotypic plasticity of male body size in two sympatric plant-inhabiting predatory mite species, Phytoseiulus persimilis and Neoseiulus californicus. These two species are similar in life history, ecological niche requirements, mating behavior, polygyny and female body size plasticity but strikingly differ in the level of both polyandry and phenotypic plasticity of male body size (both lower in P. persimilis. We hypothesized that deviations from standard body size, i.e. the size achieved under favorable conditions, incur higher costs for males in the less polyandrous P. persimilis. To test our hypotheses, we conducted two experiments on (i the effects of male body size on spermatophore transfer in singly mating females and (ii the effects of mate sequence (switching the order of standard-sized and small males on mating behavior and paternity success in doubly mating females. In P. persimilis but not N. californicus, small males transferred fewer but larger spermatophores to the females; in both species, females re-mated more likely with standard-sized following small than small following standard-sized males; in P. persimilis, first standard-sized males sired a higher proportion of offspring produced after re-mating by the female than first small males, whereas in N. californicus the paternity success of small and standard

Low level of polyandry constrains phenotypic plasticity of male body size in mites.

Science.gov (United States)

Schausberger, Peter; Walzer, Andreas; Murata, Yasumasa; Osakabe, Masahiro

2017-01-01

Polyandry, i.e. females mating with multiple males, is more common than previously anticipated and potentially provides both direct and indirect fitness benefits to females. The level of polyandry (defined by the lifetime number of male mates of a female) is an important determinant of the occurrence and intensity of sexual selection acting on male phenotypes. While the forces of sexual selection acting on phenotypic male traits such as body size are relatively well understood, sexual selection acting on phenotypic plasticity of these traits is unexplored. We tackled this issue by scrutinizing the link between polyandry and phenotypic plasticity of male body size in two sympatric plant-inhabiting predatory mite species, Phytoseiulus persimilis and Neoseiulus californicus. These two species are similar in life history, ecological niche requirements, mating behavior, polygyny and female body size plasticity but strikingly differ in the level of both polyandry and phenotypic plasticity of male body size (both lower in P. persimilis). We hypothesized that deviations from standard body size, i.e. the size achieved under favorable conditions, incur higher costs for males in the less polyandrous P. persimilis. To test our hypotheses, we conducted two experiments on (i) the effects of male body size on spermatophore transfer in singly mating females and (ii) the effects of mate sequence (switching the order of standard-sized and small males) on mating behavior and paternity success in doubly mating females. In P. persimilis but not N. californicus, small males transferred fewer but larger spermatophores to the females; in both species, females re-mated more likely with standard-sized following small than small following standard-sized males; in P. persimilis, first standard-sized males sired a higher proportion of offspring produced after re-mating by the female than first small males, whereas in N. californicus the paternity success of small and standard-sized males was

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.

Hybrid male sterility and genome-wide misexpression of male reproductive proteases.

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Gomes, Suzanne; Civetta, Alberto

2015-07-06

Hybrid male sterility is a common barrier to gene flow between species. Previous studies have posited a link between misregulation of spermatogenesis genes in interspecies hybrids and sterility. However, in the absence of fully fertile control hybrids, it is impossible to differentiate between misregulation associated with sterility vs. fast male gene regulatory evolution. Here, we differentiate between these two possibilities using a D. pseudoobscura species pair that experiences unidirectional hybrid sterility. We identify genes uniquely misexpressed in sterile hybrid male reproductive tracts via RNA-seq. The sterile male hybrids had more misregulated and more over or under expressed genes relative to parental species than the fertile male hybrids. Proteases were the only gene ontology class overrepresented among uniquely misexpressed genes, with four located within a previously identified hybrid male sterility locus. This result highlights the potential role of a previously unexplored class of genes in interspecific hybrid male sterility and speciation.

Gamma ray induced male sterility mutant in lentil

International Nuclear Information System (INIS)

Srivastava, A.; Yadav, A.K.

2001-01-01

Full text: Male sterility refers to the failure of pollen grains to bring about effective fertilization, either due to structural default or physiological disfunctioning and has special significance in hybridization programmes. Male steriles have been produced in a number of crop plants like red gram, pigeon pea, mung bean, khesari and lentil. A completely male sterile mutant was isolated in Lens culinaris Medik, after seed treatment with 100 Gy dose of gamma rays. The male sterile mutant showed 100% pollen sterility but was morphologically more vigorous than the parent plants. It showed more branches and its leaves were bigger, more oblong and dark green. The number of flowers borne by the mutant was significantly higher than any other plant of the treatment. The size of the flowers was also increased but the anthers were smaller in size. Pollen grains were few in number, round in shape but empty and did not take up any stain, indicating that normal microsporogenesis had not taken place. This male sterile mutant was used as the female parent and pollinated with pollen of a parent. Four pods with one seed in each were formed indicating that the mutant was female fertile. The seeds were smaller than those of the parent variety and also dark coloured. The mutant showed increased vigour and flower number as compared to parental plants. Lentil is an important pulse crop and induction of variability in its germplasm is necessary for its improvement. Male steriles can be used conveniently in lentil hybridization programmes. (author)

Are female healthcare workers at higher risk of occupational injury?

Science.gov (United States)

Alamgir, Hasanat; Yu, Shicheng; Drebit, Sharla; Fast, Catherine; Kidd, Catherine

2009-05-01

Differential risks of occupational injuries by gender have been examined across various industries. With the number of employees in healthcare rising and an overwhelming proportion of this workforce being female, it is important to address this issue in this growing sector. To determine whether compensated work-related injuries among females are higher than their male colleagues in the British Columbia healthcare sector. Incidents of occupational injury resulting in compensated days lost from work over a 1-year period for all healthcare workers were extracted from a standardized operational database and the numbers of productive hours were obtained from payroll data. Injuries were grouped into all injuries and musculoskeletal injuries (MSIs). Detailed analysis was conducted using Poisson regression modelling. A total of 42 332 employees were included in the study of whom 11% were male and 89% female. When adjusted for age, occupation, sub-sector, employment category, health region and facility, female workers had significantly higher risk of all injuries [rate ratio (95% CI) = 1.58 (1.24-2.01)] and MSIs [1.43 (1.11-1.85)] compared to their male colleagues. Occupational health and safety initiatives should be gender sensitive and developed accordingly.

Sex Steroid Actions in Male Bone

Science.gov (United States)

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

2014-01-01

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

Sportiness and masculinities among female and male physiotherapy students.

Science.gov (United States)

Dahl-Michelsen, Tone

2014-07-01

This article explores the gendered importance of sportiness in terms of students' judgments of themselves and their classmates as suitable physiotherapy students. The article is based on observations and qualitative interviews with students attending clinical skills training classes in the first year of a bachelor's degree program in physiotherapy in Norway. The analysis focuses on sportiness as a display of masculinity and is inspired by Connell's concept of multiple masculinities. The findings demonstrate sportiness as a shared common value among students. However, it was also found that there are two main typologies: (1) hyper-sportiness; and (2) ordinary sportiness. Male students judged as possessing hyper-sportiness are acknowledged as particularly suitable physiotherapy students and assume a hegemonic position in the student milieu. Female students who adapt hyper-sportiness have the potential to assume a hegemonic position, but tend not to do so. Female students with an ordinary level of sportiness have no particular problems in being identified as suitable physiotherapy students, whereas male students do encounter such problems. The article demonstrates how physiotherapy students' sportiness is more complex than previously known, particularly concerning differences in how female and male students are acknowledged in terms of perceived suitability as physiotherapy students. Additionally, this work shows a continuity of historical lines with respect to how sportiness is embedded in gender within the physiotherapy profession.

A chasm between injury and care: experiences of black male victims of violence.

Science.gov (United States)

Liebschutz, Jane; Schwartz, Sonia; Hoyte, Joel; Conoscenti, Lauren; Christian, Anthony B; Muhammad, Leroy; Harper, Derrick; James, Thea

2010-12-01

Despite higher rates of stabbing and shooting violence among black men, healthcare systems have not demonstrated an efficacious response to these patients. This study describes challenges and promotive factors for engaging black male violence victims of violence with medical and mental healthcare. Black male victims of stabbings and shootings were recruited through fliers and word of mouth, and were interviewed individually (n = 12) or in pairs (n = 4) using a semistructured guide. A racially diverse multidisciplinary team analyzed the data using Grounded Theory methods. Challenges to engagement with healthcare included the following: (1) Disconnect in the aftermath; e.g. participants reported not realizing they were seriously injured ("just a scratch" "poke"), were disoriented ("did not know where I was"), or were consumed with anger. (2) Institutional mistrust: blurred lines between healthcare and police, money-motivated care. (3) Foreshortened future: expectations they would die young. (4) Self-reliance: fix mental and substance abuse issues on their own. (5) Logistical issues: postinjury mental health symptoms, disability, and safety concerns created structural barriers to recovery and engagement with healthcare. Promotive factors included the following: (1) desire professionalism, open personality, and shared experience from clinicians; (2) turning points: injury or birth of a child serve as a "wake up call"; and (3) positive people, future-oriented friends and family. For black male violence victims, medical treatment did not address circumstances of and reactions to injury. Policies delineating boundaries between medical care and law enforcement and addressing postinjury mental health symptoms, disability, and safety concerns may improve the recovery process.

Female professional divers. Similarities and differences between male and female professional divers.

Science.gov (United States)

Irgens, Ågot; Troland, Kari; Grønning, Marit

2017-01-01

The aim of the present study was to explore the potential differences between female and male professional divers with regards to demographics, diving certificates, areas of diving, diving activity and health effects. The Norwegian Labour Inspection Authority's Diving certificate register contains data on all professional inshore divers who have held a certificate at any time since 1980. Forty nine per cent of these divers responded to the "Norwegian diver 2011" questionnaire. Of these divers 64 female and 1327 male divers completed the questionnaire about their professional diving career, certificate, year of onset and the year they stopped diving professionally if they were not still active in the diving industry. The level of general education was higher among female divers. More males than females were fully certified in diving. The mean age was lower among female than male fully certified divers. Fully certified female divers reported a lower total number of dives, shallower dives and diving for a shorter period of time than the male divers. They also had a lower percentage of work within the quay/construction sector and more often worked as teachers/instructors. A lower percentage of fully certified females than males had experienced decompression sickness (16.7% vs. 26.9%). Life-threatening events and psychologically challenging events were less common among females, as were adverse health effects. No such gender differences were seen for divers with a restricted certificate. The fully certified, female professional divers in our study had a very short diving career, reported fewer and shallower dives, and chose less physically demanding jobs than their male counterparts. They also had a higher level of education, reported less health problems and a better quality of life. The health effects seem to be related to the type of work rather than to gender.

Pathological characterisation of male breast cancer: Results of the EORTC 10085/TBCRC/BIG/NABCG International Male Breast Cancer Program.

Science.gov (United States)

Vermeulen, Marijn A; Slaets, Leen; Cardoso, Fatima; Giordano, Sharon H; Tryfonidis, Konstantinos; van Diest, Paul J; Dijkstra, Nizet H; Schröder, Carolien P; van Asperen, Christi J; Linderholm, Barbro; Benstead, Kim; Foekens, Renee; Martens, John W M; Bartlett, John M S; van Deurzen, Carolien H M

2017-09-01

Several prognostic histological features have been established in female breast cancer (BC), but it is unknown whether these can be extrapolated to male BC patients. The aim of this study was to evaluate the prognostic value of several histological features in a large series of male BC. Central pathology review was performed for 1483 male BCs collected through part 1 of the European Organisation for Research and Treatment of Cancer (EORTC) International Male BC Program. Pathology review included histological subtype, grade, mitotic activity index (MAI), presence of a fibrotic focus and density of tumour-infiltrating lymphocytes (TILs). These features were correlated with clinical outcome. The relationship between these features and surrogate molecular subtypes using immunohistochemistry was also assessed. Median follow-up for overall survival (OS) was 7.1 years. Overall histological grade was not significantly associated with OS (p = 0.129). MAI, the presence of a fibrotic focus and a low TIL density however were correlated with unfavourable OS (p = 0.023, p = 0.004 and p = 0.011, respectively). BC subtype correlated with TIL density (p = 0.015), as we observed a higher density for human epidermal growth factor receptor type 2 (HER2) positive BC compared to luminal HER2-negative subtype. No association was observed between subtype and fibrotic focus. Histologic grade was not significantly correlated with clinical outcome in this series, unlike what is seen in female patients. These results contribute to our understanding of male BC and indicate the importance of further research on the optimisation of risk stratification and treatment decisions for male BC patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bone benefits of testosterone replacement therapy in male hypogonadism.

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Tirabassi, G; Biagioli, A; Balercia, G

2014-06-01

Osteoporosis is an asymptomatic, systemic bone disease characterized by low bone mass and microarchitectural deterioration of bone tissue, resulting in increased bone fragility. Such condition is often underdiagnosed and undertreated, especially in men, therefore considerably increasing the fracture risk. Of note, fracture-related morbidity and mortality is generally higher in men, partly due to greater frailty. On the other hand, male hypogonadism is defined as the failure of the testes to produce androgens, sperm, or both and it is often due to the ageing process. This disorder, in turn, causes many systemic disorders, and it is the condition mainly associated with male osteoporosis. Testosterone replacement therapy (TRT) is usually prescribed to restore optimal hormone levels, but conflicting data are available about the efficacy of TRT treatment on bone mineral density. In this review we extensively examined literature data about the usefulness of TRT in improving hypogonadism-associated low bone mineral density. Furthermore, we considered the complex relationship between male osteoporosis and hypogonadism, by specifically addressing the role of androgens in male bone physiology and the diagnostic approach to male osteoporosis and hypogonadism and also by dealing with some new related aspects such as the new endocrine pathways between bone and testis and the role of androgen receptor CAG polymorphism on bone density.

Higher-order rewriting and partial evaluation

DEFF Research Database (Denmark)

Danvy, Olivier; Rose, Kristoffer H.

1998-01-01

We demonstrate the usefulness of higher-order rewriting techniques for specializing programs, i.e., for partial evaluation. More precisely, we demonstrate how casting program specializers as combinatory reduction systems (CRSs) makes it possible to formalize the corresponding program...

Bilateral male breast cancer with male potential hypogonadism

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Kurokawa Yasushi

2007-06-01

Full Text Available Abstract Background Male breast cancer is a comparatively rare disease, and simultaneous bilateral male breast cancer is considered to be an extremely rare event. Risk factors are said to be genetic factors and hormonal abnormalities due to obesity or testicular diseases. Case presentation The patient was a 47-year-old Japanese male. His family had no history of female breast cancer. This patient also had hypospadias and hormonal examination indicated the presence of primary testicular potential hypogonadism, and these hormonal abnormalities seemed to be present since childhood or the fetal period. The bilateral breast cancer developed in this man at a comparatively young age, and histopathological studies of multiple sections showed that there was almost no normal epithelial cell in the ducts, while the ducts were almost completely filled with breast cancer cells. Conclusion It is thought that male breast cancer is caused by an imbalance between estrogen and testosterone. We cannot rule out the possibility that the breast cancer developed due to the effect of the slight elevation of estrogen over a long period of time, but the actual causative factors in this patient were unable to be definitively identified. In the future, we hope to further elucidate the causes of male breast cancer.

Decline in male circumcision in South Korea.

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Kim, DaiSik; Koo, Sung-Ae; Pang, Myung-Geol

2012-12-11

To investigate the changing circumcision rate in South Korea in the last decade and to propose underlying causes for this change, in the context of the present fluctuating world-wide trends in circumcision. From 2009 to 2011, 3,296 South Korean males (or their parents) aged 0-64 years were asked about their circumcision status, their age at circumcision, and their information level regarding circumcision. We employed non-probability sampling considering the sensitive questions on the study theme. Currently the age-standardized circumcision rate for South Korean males aged 14-29 is found to be 75.8%. In an earlier study performed in 2002, the rate for the same age group was 86.3%. Of particular interest, males aged 14-16 show a circumcision rate of 56.4%, while the same age group 10 years ago displayed a much higher percentage, at 88.4%. In addition, the extraordinarily high circumcision rate of 95.2% found 10 years ago for the 17-19 age group is now reduced to 74.4%. Interestingly, of the circumcised males, the percentage circumcised in the last decade was only 25.2%; i.e., the majority of the currently circumcised males had undergone the operation prior to 2002, indicating that the actual change in the last decade is far greater. Consistent with this conjecture, the 2002 survey showed that the majority of circumcised males (75.7%) had undergone the operation in the decade prior to that point. Focusing on the flagship age group of 14-16, this drop suggests that, considering the population structure of Korean males, approximately one million fewer circumcision operations have been performed in the last decade relative to the case of non-decline. This decline is strongly correlated with the information available through internet, newspapers, lectures, books, and television: within the circumcised population, both the patients and their parents had less prior knowledge regarding circumcision, other than information obtained from person to person by oral communication

Do Vocational Pathways Improve Higher Education Access for Women and Men from Less Privileged Social Backgrounds? : A Comparison of Vocational Tracks to Higher Education in France and Switzerland

OpenAIRE

Imdorf, Christian; Koomen, Maarten; Murdoch, Jake; Guégnard, Christine

2017-01-01

International audience; Educational policy developments in France and Switzerland have increased eligibility for higher education. This paper explores the extent to which vocationally orientated pathways to higher education reduce social inequalities in France and Switzerland. More specifically, we analyse how the vocational pathway facilitates access to higher education for male and female students from lower cultural capital backgrounds. We refer to gender theory to link young people's subj...

Risk of abdominal aortic aneurysm (AAA) among male and female relatives of AAA patients.

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van de Luijtgaarden, Koen M; Rouwet, Ellen V; Hoeks, Sanne E; Stolker, Robert J; Verhagen, Hence Jm; Majoor-Krakauer, Danielle

2017-04-01

Sex affects the presentation, treatment, and outcomes of abdominal aortic aneurysm (AAA). Although AAAs are less prevalent in women, at least in the general population, women with an AAA have a poorer prognosis in comparison to men. Sex differences in the genetic predisposition for aneurysm disease remain to be established. In this study we investigated the familial risk of AAA for women compared to men. All living AAA patients included in a 2004-2012 prospective database were invited to the multidisciplinary vascular/genetics outpatient clinic between 2009 and 2012 for assessment of family history using detailed questionnaires. AAA risk for male and female relatives was calculated separately and stratified by sex of the AAA patients. Families of 568 AAA patients were investigated and 22.5% of the patients had at least one affected relative. Female relatives had a 2.8-fold and male relatives had a 1.7-fold higher risk than the estimated sex-specific population risk. Relatives of female AAA patients had a higher aneurysm risk than relatives of male patients (9.0 vs 5.9%, p = 0.022), corresponding to 5.5- and 2.0-fold increases in aneurysm risk in the female and male relatives, respectively. The risk for aortic aneurysm in relatives of AAA patients is higher than expected from population risk. The excess risk is highest for the female relatives of AAA patients and for the relatives of female AAA patients. These findings endorse targeted AAA family screening for female and male relatives of all AAA patients.

Salary discrepancies between practicing male and female physician assistants.

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Coplan, Bettie; Essary, Alison C; Virden, Thomas B; Cawley, James; Stoehr, James D

2012-01-01

Salary discrepancies between male and female physicians are well documented; however, gender-based salary differences among clinically practicing physician assistants (PAs) have not been studied since 1992 (Willis, 1992). Therefore, the objectives of the current study are to evaluate the presence of salary discrepancies between clinically practicing male and female PAs and to analyze the effect of gender on income and practice characteristics. Using data from the 2009 American Academy of Physician Assistants' (AAPA) Annual Census Survey, we evaluated the salaries of PAs across multiple specialties. Differences between men and women were compared for practice characteristics (specialty, experience, etc) and salary (total pay, base pay, on-call pay, etc) in orthopedic surgery, emergency medicine, and family practice. Men reported working more years as a PA in their current specialty, working more hours per month on-call, providing more direct care to patients, and more funding available from their employers for professional development (p pay, overtime pay, administrative pay, on-call pay, and incentive pay based on productivity and performance (p pay (p = .001) in orthopedic surgery, higher total income (p = .011) and base pay (p = .005) in emergency medicine, and higher base pay in family practice (p discrepancies remain between employed male and female PAs regardless of specialty, experience, or other practice characteristics. Copyright © 2012. Published by Elsevier Inc.

Male contraception.

Science.gov (United States)

Amory, John K

2016-11-01

Although female contraceptives are very effective at preventing unintended pregnancy, some women can not use them because of health conditions or side-effects, leaving some couples without effective contraceptive options. In addition, many men wish to take active responsibility for family planning. Thus, there is a great need for male contraceptives to prevent unintended pregnancies, of which 80-90 million occur annually. At present, effective male contraceptive options are condoms and vasectomy, which are not ideal for all men. Therefore, efforts are under way to develop novel male contraceptives. This paper briefly reviews the advantages and disadvantages of condoms and vasectomies and then discusses the research directed toward development of novel methods of male contraception. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Individual and seasonal variation in fecal testosterone and cortisol levels of wild male tufted capuchin monkeys, Cebus apella nigritus.

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Lynch, Jessica W; Ziegler, Toni E; Strier, Karen B

2002-05-01

This study tested the "challenge hypothesis" and rank-based predictions for temporal steroid production in male tufted capuchin monkeys, Cebus apella. Fecal samples (n = 209) collected from six wild males were analyzed for testosterone and cortisol concentration by enzyme immunoassay. The temporal pattern in male steroid production was compared to female sexual activity and rates of male aggression. The top-ranking adult male did not differ from other adult males in testosterone or cortisol concentration. Mean adult testosterone was significantly higher than mean subadult testosterone throughout the year. There was a clear elevation of testosterone and cortisol in both adult and subadult males during the peak of adult female sexual activity after the birth season. In fact, the magnitude of increase in testosterone was higher than predicted for a species with low male-male aggression. However, there was no difference between nonbreeding baseline testosterone levels during the birth season, and the "breeding" baseline of testosterone in males found during asynchronous female sexual activity. Of all behavioral indices examined, the distribution of female-maintained consortships was the best predictor of mean adult male testosterone concentrations. Although in many species, elevated testosterone coincides with increased male-male aggression, in the present study, the sustained high-magnitude increase in steroids during the peak of adult female sexual activity was associated with a relatively low rate of male-male intragroup aggression. (c) 2002 Elsevier Science (USA).

Reduction of dopamine level enhances the attractiveness of male Drosophila to other males.

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Liu, Tong; Dartevelle, Laurence; Yuan, Chunyan; Wei, Hongping; Wang, Ying; Ferveur, Jean-François; Guo, Aike

2009-01-01

Dopamine is an important neuromodulator in animals and its roles in mammalian sexual behavior are extensively studied. Drosophila as a useful model system is widely used in many fields of biological studies. It has been reported that dopamine reduction can affect female receptivity in Drosophila and leave male-female courtship behavior unaffected. Here, we used genetic and pharmacological approaches to decrease the dopamine level in dopaminergic cells in Drosophila, and investigated the consequence of this manipulation on male homosexual courtship behavior. We find that reduction of dopamine level can induce Drosophila male-male courtship behavior, and that this behavior is mainly due to the increased male attractiveness or decreased aversiveness towards other males, but not to their enhanced propensity to court other males. Chemical signal input probably plays a crucial role in the male-male courtship induced by the courtees with reduction of dopamine. Our finding provides insight into the relationship between the dopamine reduction and male-male courtship behavior, and hints dopamine level is important for controlling Drosophila courtship behavior.

Are 1994 alcohol production and the sales deregulation policy in Japan associated with increased road traffic fatalities among adult and teenage males and females in Japan?

Science.gov (United States)

Desapriya, Ediriweera; Fujiwara, Takeo; Scime, Giulia; Sasges, Deborah; Pike, Ian; Shimizu, Shinji

2009-10-01

International studies have shown a significant association between alcohol availability and traffic crashes that involve alcohol-impaired drivers. A key limitation to previous alcohol availability and motor vehicle crash (MVC) evaluation research is the assumption of population homogeneity in responding to the policies. The present analysis focuses on the evaluation of the impact of alcohol availability on different segments of the Japanese population by comparing MVC fatality rates from before and after implementation of the alcohol deregulation policy in 1994. Poisson regression with robust standard error was used to model the before-to-after change in incidence rate ratios (IRR) in adult males, adult females, teenage males and teenage females. To control potential confounders, unemployment rate, vehicle miles of travel (VMT), vehicle registration, and number of drivers licensed in Japan were added to the model. The exponents of the fitted coefficients are equivalent to incidence rate ratios. Implementation of the policy deregulating alcohol sales and production did not appear to increase traffic fatalities among adult or teenage males or females in Japan. We found that male adult fatalities demonstrated a statistically significant decline following enactment of the deregulation policy in 1994. Contrary to previous research, the findings of this study demonstrated lower rates of fatalities and higher compliance with alcohol-related driving legislation in Japanese society following implementation of the deregulation policy in 1994. Further well designed, nonaligned studies on alcohol availability and traffic fatalities in other countries are urgently needed.

Increased progesterone production in cumulus-oocyte complexes of female mice sired by males with the Y-chromosome long arm deletion and its potential influence on fertilization efficiency.

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Kotarska, Katarzyna; Galas, Jerzy; Przybyło, Małgorzata; Bilińska, Barbara; Styrna, Józefa

2015-02-01

It was revealed previously that B10.BR(Y(del)) females sired by males with the Y-chromosome long arm deletion differ from genetically identical B10.BR females sired by males with the intact Y chromosome. This is interpreted as a result of different epigenetic information which females of both groups inherit from their fathers. In the following study, we show that cumulus-oocyte complexes ovulated by B10.BR(Y(del)) females synthesize increased amounts of progesterone, which is important sperm stimulator. Because their extracellular matrix is excessively firm, the increased progesterone secretion belongs presumably to factors that compensate this feature enabling unchanged fertilization ratios. Described compensatory mechanism can act only on sperm of high quality, presenting proper receptors. Indeed, low proportion of sperm of Y(del) males that poorly fertilize B10.BR(Y(del)) oocytes demonstrates positive staining of membrane progesterone receptors. This proportion is significantly higher for sperm of control males that fertilize B10.BR(Y(del)) and B10.BR oocytes with the same efficiency. © The Author(s) 2014.

Pharmacokinetics of propafenone hydrochloride sustained-release capsules in male beagle dogs.

Science.gov (United States)

Pan, Liping; Qian, Yafang; Cheng, Minlu; Gu, Pan; He, Yanna; Xu, Xiaowen; Ding, Li

2015-01-01

This paper describes the development and validation of a liquid chromatography-mass spectrometric assay for propafenone and its application to a pharmacokinetic study of propafenone administered as a new propafenone hydrochloride sustained-release capsule (SR-test), as an instant-release tablet (IR-reference) and as the market leader sustained-release capsule (Rythmol, SR-reference) in male beagle dogs (n=8). In Study A comparing SR-test with IR-reference in a crossover design T max and t 1/2 of propafenone for SR-test were significantly higher than those for IR-reference while C max and AUC were lower demonstrating the sustained release properties of the new formulation. In Study B comparing SR-test with SR-reference the observed C max and AUC of propafenone for SR-test (124.5±140.0 ng/mL and 612.0±699.2 ng·h/mL, respectively) were higher than for SR-reference (78.52±72.92 ng/mL and 423.6±431.6 ng·h/mL, respectively) although the differences were not significant. Overall, the new formulation has as good if not better sustained release characteristics to the market leader formulation.

Pharmacokinetics of propafenone hydrochloride sustained-release capsules in male beagle dogs

Directory of Open Access Journals (Sweden)

Liping Pan

2015-01-01

Full Text Available This paper describes the development and validation of a liquid chromatography–mass spectrometric assay for propafenone and its application to a pharmacokinetic study of propafenone administered as a new propafenone hydrochloride sustained-release capsule (SR-test, as an instant-release tablet (IR-reference and as the market leader sustained-release capsule (Rythmol, SR-reference in male beagle dogs (n=8. In Study A comparing SR-test with IR-reference in a crossover design Tmax and t1/2 of propafenone for SR-test were significantly higher than those for IR-reference while Cmax and AUC were lower demonstrating the sustained release properties of the new formulation. In Study B comparing SR-test with SR-reference the observed Cmax and AUC of propafenone for SR-test (124.5±140.0 ng/mL and 612.0±699.2 ng·h/mL, respectively were higher than for SR-reference (78.52±72.92 ng/mL and 423.6±431.6 ng·h/mL, respectively although the differences were not significant. Overall, the new formulation has as good if not better sustained release characteristics to the market leader formulation.

Stress-relevant social behaviors of middle-class male cynomolgus monkeys (Macaca fascicularis).

Science.gov (United States)

Cui, Ding; Zhou, Yuan

2015-11-18

Stress from dominance ranks in human societies, or that of other social animals, especially nonhuman primates, can have negative influences on health. Individuals holding different social status may be burdened with various stress levels. The middle class experiences a special stress situation within the dominance hierarchy due to its position between the higher and lower classes. Behaviorally, questions about where middle-class stress comes from and how individuals adapt to middle-class stress remain poorly understood in nonhuman primates. In the present study, social interactions, including aggression, avoidance, grooming and mounting behaviors, between beta males, as well as among group members holding higher or lower social status, were analyzed in captive male-only cynomolgus monkey groups. We found that aggressive tension from the higher hierarchy members was the main origin of stress for middle-class individuals. However, behaviors such as attacking lower hierarchy members immediately after being the recipient of aggression, as well as increased avoidance, grooming and mounting toward both higher and lower hierarchy members helped alleviate middle-class stress and were particular adaptations to middle-class social status.

Juvenile hormone-dopamine systems for the promotion of flight activity in males of the large carpenter bee Xylocopa appendiculata

Science.gov (United States)

Sasaki, Ken; Nagao, Takashi

2013-12-01

The reproductive roles of dopamine and dopamine regulation systems are known in social hymenopterans, but the knowledge on the regulation systems in solitary species is still needed. To test the possibility that juvenile hormone (JH) and brain dopamine interact to trigger territorial flight behavior in males of a solitary bee species, the effects on biogenic amines of JH analog treatments and behavioral assays with dopamine injections in males of the large carpenter bee Xylocopa appendiculata were quantified. Brain dopamine levels were significantly higher in methoprene-treated males than in control males 4 days after treatment, but were not significantly different after 7 days. Brain octopamine and serotonin levels did not differ between methoprene-treated and control males at 4 and 7 days after treatment. Injection of dopamine caused significantly higher locomotor activities and a shorter duration for flight initiation in experimental versus control males. These results suggest that brain dopamine can be regulated by JH and enhances flight activities in males. The JH-dopamine system in males of this solitary bee species is similar to that of males of the highly eusocial honeybee Apis mellifera.

Disease spectrum and treatment patterns in a local male infertility clinic.

Science.gov (United States)

Ho, K L; Tsu, James H L; Tam, P C; Yiu, M K

2015-02-01

To review disease spectrum and treatment patterns in a local male infertility clinic. Case series. Male infertility clinic in a teaching hospital in Hong Kong. Patients who were seen as new cases in a local male infertility clinic between January 2008 and December 2012. Infertility assessment and counselling on treatment options. Disease spectrum and treatment patterns. A total of 387 new patients were assessed in the male infertility clinic. The mean age of the patients and their female partners was 37.2 and 32.1 years, respectively. The median duration of infertility was 3 years. Among the patients, 36.2% had azoospermia, 8.0% had congenital absence of vas deferens, and 48.3% of patients had other abnormalities in semen parameters. The commonest causes of male infertility were unknown (idiopathic), clinically significant varicoceles, congenital absence of vas deferens, mumps after puberty, and erectile or ejaculatory dysfunction. Overall, 66.1% of patients chose assisted reproductive treatment and 12.4% of patients preferred surgical correction of reversible male infertility conditions. Altogether 36.7% of patients required either surgical sperm retrieval or correction of male infertility conditions. The present study provided important local data on the disease spectrum and treatment patterns in a male infertility clinic. The incidences of azoospermia and congenital absence of vas deferens were much higher than those reported in the contemporary literature. A significant proportion of patients required either surgical sperm retrieval or correction of reversible male infertility conditions.

Difference in kinematical behavior between two landing tasks in male volleyball athletes

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Glauber Ribeiro Pereira

2010-09-01

Full Text Available Anterior cruciate ligament (ACL injuries are common in sports. Studies investigating injury mechanisms have demonstrated that most injuries arise from landing tasks. Despite the demonstration of differences between male and female kinematics, there are no studies showing how males behave during different landing tasks. The objective of this study was to compare the angular and temporal kinematics of the lower limbs between two different landing tasks. Double leg and single leg landings were recorded in the frontal and sagittal plane in 15 male volleyball athletes by videogrammetry. Reduced hip and knee flexion and increased knee valgus were observed in the single leg landing task compared to the double leg landing task. No significant difference in landing time was observed between the two tasks. In conclusion, the results support the premise that lower limb kinematics change according to the task performed. Further studies are necessary to explore the impact of these kinematic differences on knee loading and to relate them to ACL injury mechanisms in men.

Male sexual ornament size is positively associated with reproductive morphology and enhanced fertility in the stalk-eyed fly Teleopsis dalmanni

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Chapman Tracey

2008-08-01

Full Text Available Abstract Background Exaggerated male ornaments and displays often evolve in species where males only provide females with ejaculates during reproduction. Although "good genes" arguments are typically invoked to explain this phenomenon, a simpler alternative is possible if variation in male reproductive quality (e.g. sperm number, ejaculate content, mating rate is an important determinant of female reproductive success. The "phenotype-linked fertility hypothesis" states that female preference for male ornaments or displays has been selected to ensure higher levels of fertility and has driven the evolution of exaggerated male traits. Females of the stalk-eyed fly Teleopsis dalmanni must mate frequently to maintain high levels of fertility and prefer to mate with males exhibiting large eyespan, a condition-dependent sexual ornament. If eyespan indicates male reproductive quality, females could directly increase their reproductive success by mating with males with large eyespan. Here we investigate whether male eyespan indicates accessory gland and testis length, and then ask whether mating with large eyespan males affects female fertility. Results Male eyespan was a better predictor of two key male reproductive traits – accessory gland and testis length – than was body size alone. This positive relationship held true over three levels of increasing environmental stress during the maturation of the adult accessory glands and testes. Furthermore, females housed with a large eyespan male exhibited higher levels of fertility than those with small eyespan males. Conclusion Male eyespan in stalk-eyed flies is subject to strong directional mate preference and is a reliable indicator of male reproductive quality – both because males with larger eyespan have bigger accessory glands and testes, and also as they confer higher fertility on females. Fertility enhancement may have arisen because males with larger eyespan mated more often and/or because

Insights into Sexism: Male Status and Performance Moderates Female-Directed Hostile and Amicable Behaviour.

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Michael M Kasumovic

Full Text Available Gender inequality and sexist behaviour is prevalent in almost all workplaces and rampant in online environments. Although there is much research dedicated to understanding sexist behaviour, we have almost no insight into what triggers this behaviour and the individuals that initiate it. Although social constructionist theory argues that sexism is a response towards women entering a male dominated arena, this perspective doesn't explain why only a subset of males behave in this way. We argue that a clearer understanding of sexist behaviour can be gained through an evolutionary perspective that considers evolved differences in intra-sexual competition. We hypothesised that female-initiated disruption of a male hierarchy incites hostile behaviour from poor performing males who stand to lose the most status. To test this hypothesis, we used an online first-person shooter video game that removes signals of dominance but provides information on gender, individual performance, and skill. We show that lower-skilled players were more hostile towards a female-voiced teammate, especially when performing poorly. In contrast, lower-skilled players behaved submissively towards a male-voiced player in the identical scenario. This difference in gender-directed behaviour became more extreme with poorer focal-player performance. We suggest that low-status males increase female-directed hostility to minimize the loss of status as a consequence of hierarchical reconfiguration resulting from the entrance of a woman into the competitive arena. Higher-skilled players, in contrast, were more positive towards a female relative to a male teammate. As higher-skilled players have less to fear from hierarchical reorganization, we argue that these males behave more positively in an attempt to support and garner a female player's attention. Our results provide the clearest picture of inter-sexual competition to date, highlighting the importance of considering an evolutionary

Insights into Sexism: Male Status and Performance Moderates Female-Directed Hostile and Amicable Behaviour.

Science.gov (United States)

Kasumovic, Michael M; Kuznekoff, Jeffrey H

2015-01-01

Gender inequality and sexist behaviour is prevalent in almost all workplaces and rampant in online environments. Although there is much research dedicated to understanding sexist behaviour, we have almost no insight into what triggers this behaviour and the individuals that initiate it. Although social constructionist theory argues that sexism is a response towards women entering a male dominated arena, this perspective doesn't explain why only a subset of males behave in this way. We argue that a clearer understanding of sexist behaviour can be gained through an evolutionary perspective that considers evolved differences in intra-sexual competition. We hypothesised that female-initiated disruption of a male hierarchy incites hostile behaviour from poor performing males who stand to lose the most status. To test this hypothesis, we used an online first-person shooter video game that removes signals of dominance but provides information on gender, individual performance, and skill. We show that lower-skilled players were more hostile towards a female-voiced teammate, especially when performing poorly. In contrast, lower-skilled players behaved submissively towards a male-voiced player in the identical scenario. This difference in gender-directed behaviour became more extreme with poorer focal-player performance. We suggest that low-status males increase female-directed hostility to minimize the loss of status as a consequence of hierarchical reconfiguration resulting from the entrance of a woman into the competitive arena. Higher-skilled players, in contrast, were more positive towards a female relative to a male teammate. As higher-skilled players have less to fear from hierarchical reorganization, we argue that these males behave more positively in an attempt to support and garner a female player's attention. Our results provide the clearest picture of inter-sexual competition to date, highlighting the importance of considering an evolutionary perspective when

Bilateral Killian-Jamieson diverticula demonstrated by videofluoroscopic swallowing study: case report

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Betina Scheeren

2013-06-01

Full Text Available The authors report the case of a 56-year-old male patient complaining of dysphagia for solids and food impaction, submitted to videofluoroscopic swallowing study that demonstrated the presence of two esophageal diverticula. The videofluoroscopic swallowing study was critical in the identification and diagnosis of the diverticula, an esophageal cause of dysphagia.

The prevalence of coeliac disease is significantly higher in children compared with adults.

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Mariné, M; Farre, C; Alsina, M; Vilar, P; Cortijo, M; Salas, A; Fernández-Bañares, F; Rosinach, M; Santaolalla, R; Loras, C; Marquès, T; Cusí, V; Hernández, M I; Carrasco, A; Ribes, J; Viver, J M; Esteve, M

2011-02-01

Some limited studies of coeliac disease have shown higher frequency of coeliac disease in infancy and adolescence than in adulthood. This finding has remained unnoticed and not adequately demonstrated. To assess whether there are age and gender differences in coeliac disease prevalence. A total of 4230 subjects were included consecutively (1 to ≥80 years old) reproducing the reference population by age and gender. Sample size was calculated assuming a population-based coeliac disease prevalence of 1:250. After an interim analysis, the paediatric sample was expanded (2010 children) due to high prevalence in this group. Anti-transglutaminase and antiendomysial antibodies were determined and duodenal biopsy was performed if positive. Log-linear models were fitted to coeliac disease prevalence by age allowing calculation of percentage change of prevalence. Differences between groups were compared using Chi-squared test. Twenty-one subjects had coeliac disease (male/female 1:2.5). Coeliac disease prevalence in the total population was 1:204. Coeliac disease prevalence was higher in children (1:71) than in adults (1:357) (P = 0.00005). A significant decrease of prevalence in older generations was observed [change of prevalence by age of -5% (95% CI: -7.58 to -2.42%)]. In the paediatric expanded group (1-14 years), a decrease of coeliac disease prevalence was also observed [prevalence change: -17% (95% CI: -25.02 to -6.10)]. The prevalence of coeliac disease in childhood was five times higher than in adults. Whether this difference is due to environmental factors influencing infancy, or latency of coeliac disease in adulthood, remains to be demonstrated in prospective longitudinal studies. © 2010 Blackwell Publishing Ltd.

Acoustic Method for Testing the Quality of Sterilized Male Tsetse Flies Glossina Pallidipes

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Kratochvil, H [Department of Evolutionary Biology, University of Vienna, Halsriegelstr. 34, Vienna A-1090 (Austria); Noll, A [Institut fuer Schallforschung, Oe Ak d Wiss, Wohllebengasse 12-14, Vienna A-1040 (Austria); Bolldorf, J [Umweltbundesamt, Spittelauer Laende 5, Vienna A-1090 (Austria); Parker, A G [Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, FAO/IAEA Agriculture and Biotechnology Laboratory, Seibersdorf A-2444 (Austria)

2012-07-15

Tsetse flies are able to emit different acoustic signals. An acoustic method to test the quality of sterilized male tsetse flies was developed. Differences in the sound characteristics between males and females, between sterilized and unsterilized males, and between males sterilized in air and nitrogen, were determined. Also, the acoustic parameters (frequency, time, sound pressure level) of the sounds that are useful as criteria for quality control were determined. It was demonstrated that only the so-called 'feeding sounds' can be used as a quality criterion. Both sexes emitted feeding sounds while feeding on a host. These sounds were also used to find sexual partners, and had an effect on male copulation success. An acoustic sound analysis programme was developed; it automatically measured sound activity (only feeding sounds) under standard conditions (random sample, relative humidity, temperature, light intensity). (author)

Increased cardiovascular reactivity to acute stress and salt-loading in adult male offspring of fat fed non-obese rats.

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Olena Rudyk

Full Text Available Diet-induced obesity in rat pregnancy has been shown previously to be associated with consistently raised blood pressure in the offspring, attributed to sympathetic over-activation, but the relative contributions to this phenotype of maternal obesity versus raised dietary fat is unknown. Sprague-Dawley female rats were fed either a control (4.3% fat, n = 11 or lard-enriched (23.6% fat, n = 16 chow 10 days prior to mating, throughout pregnancy and lactation. In conscious adult (9-month-old offspring cardiovascular parameters were measured (radiotelemetry. The short period of fat-feeding did not increase maternal weight versus controls and the baseline blood pressure was similar in offspring of fat fed dams (OF and controls (OC. However, adult male OF showed heightened cardiovascular reactivity to acute restraint stress (p<0.01; Δ systolic blood pressure (SBP and Δheart rate (HR with a prolonged recovery time compared to male OC. α1/β-adrenergic receptor blockade normalised the response. Also, after dietary salt-loading (8%-NaCl ad libitum for 1 week male OF demonstrated higher SBP (p<0.05 in the awake phase (night-time and increased low/high frequency ratio of power spectral density of HR variability versus OC. Baroreflex gain and basal power spectral density components of the heart rate or blood pressure were similar in male OF and OC. Minor abnormalities were evident in female OF. Fat feeding in the absence of maternal obesity in pregnant rats leads to altered sympathetic control of cardiovascular function in adult male offspring, and hypertension in response to stressor stimuli.

Estrogens and male reproduction: a new concept

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S. Carreau

2007-06-01

Full Text Available The mammalian testis serves two main functions: production of spermatozoa and synthesis of steroids; among them estrogens are the end products obtained from the irreversible transformation of androgens by a microsomal enzymatic complex named aromatase. The aromatase is encoded by a single gene (cyp19 in humans which contains 18 exons, 9 of them being translated. In rats, the aromatase activity is mainly located in Sertoli cells of immature rats and then in Leydig cells of adult rats. We have demonstrated that germ cells represent an important source of estrogens: the amount of P450arom transcript is 3-fold higher in pachytene spermatocytes compared to gonocytes or round spermatids; conversely, aromatase activity is more intense in haploid cells. Male germ cells of mice, bank voles, bears, and monkeys express aromatase. In humans, we have shown the presence of a biologically active aromatase and of estrogen receptors (alpha and ß in ejaculated spermatozoa and in immature germ cells in addition to Leydig cells. Moreover, we have demonstrated that the amount of P450arom transcripts is 30% lower in immotile than in motile spermatozoa. Alterations of spermatogenesis in terms of number and motility of spermatozoa have been described in men genetically deficient in aromatase. These last observations, together with our data showing a significant decrease of aromatase in immotile spermatozoa, suggest that aromatase could be involved in the acquisition of sperm motility. Thus, taking into account the widespread localization of aromatase and estrogen receptors in testicular cells, it is obvious that, besides gonadotrophins and androgens, estrogens produced locally should be considered to be physiologically relevant hormones involved in the regulation of spermatogenesis and spermiogenesis.

Worthless donations: male deception and female counter play in a nuptial gift-giving spider.

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Albo, Maria J; Winther, Gudrun; Tuni, Cristina; Toft, Søren; Bilde, Trine

2011-11-14

In nuptial gift-giving species, benefits of acquiring a mate may select for male deception by donation of worthless gifts. We investigated the effect of worthless gifts on mating success in the spider Pisaura mirabilis. Males usually offer an insect prey wrapped in silk; however, worthless gifts containing inedible items are reported. We tested male mating success in the following experimental groups: protein enriched fly gift (PG), regular fly gift (FG), worthless gift (WG), or no gift (NG). Males that offered worthless gifts acquired similar mating success as males offering nutritional gifts, while males with no gift experienced reduced mating success. The results suggest that strong selection on the nuptial gift-giving trait facilitates male deception by donation of worthless gifts. Females terminated matings faster when males offered worthless donations; this demonstrate a cost of deception for the males as shorter matings lead to reduced sperm transfer and thus give the deceiving males a disadvantage in sperm competition. We propose that the gift wrapping trait allows males to exploit female foraging preference by disguising the gift content thus deceiving females into mating without acquiring direct benefits. Female preference for a genuine prey gift combined with control over mating duration, however, counteracts the male deception.

Group management influences reproductive function of the male cheetah (Acinonyx jubatus).

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Koester, Diana C; Freeman, Elizabeth W; Wildt, David E; Terrell, Kimberly A; Franklin, Ashley D; Meeks, Karen; Crosier, Adrienne E

2017-03-01

Although the free-ranging cheetah is generally socially solitary, as many as 60% of males live in same-sex (usually sibling) coalitions. Under ex situ conditions, the cheetah experiences low reproductive success with only ~18% of males having ever produced young. Most male cheetahs (85%) are managed in captivity in coalitions, but with no data on the influence of social grouping on reproductive parameters. We examined the influence of singleton versus coalition management on various male cheetah physiological traits, including ejaculate quality and gonadal and adrenal hormone metabolite concentrations. We also assessed behaviour within coalitions for evidence of social hierarchy through initiation of interactions with group mates and relatedness to physiological traits. Ejaculate quality (including total motile and structurally normal spermatozoa per ejaculate) and androgen concentration profiles were higher (Pcheetah, specifically related to the development of normal, motile spermatozoa and androgen production, is influenced by management with same-sex conspecifics. The findings have implications for ex situ conservation breeding programs by suggesting that reproductive quality can be enhanced through group maintenance of cheetah males.

Experimental Demonstration of Higher Precision Weak-Value-Based Metrology Using Power Recycling

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Wang, Yi-Tao; Tang, Jian-Shun; Hu, Gang; Wang, Jian; Yu, Shang; Zhou, Zong-Quan; Cheng, Ze-Di; Xu, Jin-Shi; Fang, Sen-Zhi; Wu, Qing-Lin; Li, Chuan-Feng; Guo, Guang-Can

2016-12-01

The weak-value-based metrology is very promising and has attracted a lot of attention in recent years because of its remarkable ability in signal amplification. However, it is suggested that the upper limit of the precision of this metrology cannot exceed that of classical metrology because of the low sample size caused by the probe loss during postselection. Nevertheless, a recent proposal shows that this probe loss can be reduced by the power-recycling technique, and thus enhance the precision of weak-value-based metrology. Here we experimentally realize the power-recycled interferometric weak-value-based beam-deflection measurement and obtain the amplitude of the detected signal and white noise by discrete Fourier transform. Our results show that the detected signal can be strengthened by power recycling, and the power-recycled weak-value-based signal-to-noise ratio can surpass the upper limit of the classical scheme, corresponding to the shot-noise limit. This work sheds light on higher precision metrology and explores the real advantage of the weak-value-based metrology over classical metrology.

Leadership Behavior of Male and Female Managers, 1984-2002

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Robinson, Jill L.; Lipman-Blumen, Jean

2003-01-01

Using data collected from 1984 to 2002 from 2,371 male and 1,768 female middle and senior managers in the United States, the authors of this article demonstrate not only that traditional gender role stereotypes do "not" hold up, but also that counterstereotypical patterns exist. Using the Connective Leadership Model, based on nine sets…

Shadow of domestic violence and extramarital sex cohesive with spousal communication among males in Nepal

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2014-01-01

Background Public health and human right issues are challenging in low and middle income countries. The main objectives of this paper were to determine the prevalence and factors associated with domestic violence, extramarital sex, and spousal communication among male. Methods A cross-sectional study among 2466 married males in Kathmandu, Nepal was conducted using random sampling method. Adjusted odds ratios (AORs) and 95% confidence intervals (CI) of associated factors were estimated by stepwise backward likelihood ratio method. Results Prevalence of domestic violence was 63.14% (95% CI 61.20-65.05), extramarital sex was 32.12% (95% CI 30.27-34.00), and spousal communication was 48.87% (95% CI 46.85-50.90). Nearly one in five male (18.20%) had not used condom during extramarital sex. Interestingly, male who had more than three or equal children were less likely to have perpetrated domestic violence compared with those who had less children. Older male aged 25 and above were more likely (AORs = 1.55, 95% CI 1.19-2.03) to have extramarital sex compared with male aged 24 or below. Those male who had studied secondary or higher level of education were less likely to have extramarital sex compared to those who had primary level or no education. Male who had higher income were more likely to have spousal communication compared to those who had less income. Surprisingly, those male who had extramarital sex were less likely to have spousal communication compared with those was not involved in extramarital sex. Conclusion Practice of domestic violence and extramarital sex is quite common among married male in Nepal, where spousal communication is sparse. These findings can be used to advocate for immediate attention and activities needs to be endorsed by policymakers and programmers. PMID:24924872

A simple genetic incompatibility causes hybrid male sterility in mimulus.

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Sweigart, Andrea L; Fishman, Lila; Willis, John H

2006-04-01

Much evidence has shown that postzygotic reproductive isolation (hybrid inviability or sterility) evolves by the accumulation of interlocus incompatibilities between diverging populations. Although in theory only a single pair of incompatible loci is needed to isolate species, empirical work in Drosophila has revealed that hybrid fertility problems often are highly polygenic and complex. In this article we investigate the genetic basis of hybrid sterility between two closely related species of monkeyflower, Mimulus guttatus and M. nasutus. In striking contrast to Drosophila systems, we demonstrate that nearly complete hybrid male sterility in Mimulus results from a simple genetic incompatibility between a single pair of heterospecific loci. We have genetically mapped this sterility effect: the M. guttatus allele at the hybrid male sterility 1 (hms1) locus acts dominantly in combination with recessive M. nasutus alleles at the hybrid male sterility 2 (hms2) locus to cause nearly complete hybrid male sterility. In a preliminary screen to find additional small-effect male sterility factors, we identified one additional locus that also contributes to some of the variation in hybrid male fertility. Interestingly, hms1 and hms2 also cause a significant reduction in hybrid female fertility, suggesting that sex-specific hybrid defects might share a common genetic basis. This possibility is supported by our discovery that recombination is reduced dramatically in a cross involving a parent with the hms1-hms2 incompatibility.

Condom use in incarcerated adolescent males: knowledge and practice.

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Bortot, Andrea T; Risser, William L; Cromwell, Polly F

2006-01-01

Information is limited on how well adolescents use condoms and where they learn how. The objective of this study was to determine how often incarcerated males used condoms incorrectly and where, how, and from whom they learned condom use. This study consisted of an interviewer-administered survey during intake physicals at a juvenile detention center. Results were based on self-report; condom use models were not used. During usual use among 141 males, errors included failure to secure the condom to the penis on withdrawal (37%), loss of erection before condom removal (18%), and failure to leave space at the tip (14%). Learning occurred at home (27%), school (23%), probation/detention facilities (14%), and community programs (3.4%). Subjects learned from educators/counselors (37%), family (27%), and friends (6.9%). Methods of learning included reading the package insert (45%), demonstrations (39%), explanations (33%), and media (19%). These adolescents had relatively few condom errors. Common methods of learning correct condom use included observing a demonstration, reading the package insert, and hearing an explanation. The last 2 methods are easy to implement.

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

DEFF Research Database (Denmark)

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...

Male Infertility

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... hypothalamus, pituitary, thyroid and adrenal glands. Low testosterone (male hypogonadism) and other hormonal problems have a number of possible underlying causes. Defects of tubules that transport sperm. Many ... syndrome — in which a male is born with two X chromosomes and one ...

Relationship between blood groups and male infertility

International Nuclear Information System (INIS)

Ahmed, I.; Naeem, M.; Samad, A.; Nasir, A.; Aman, Z.; Ahmed, S.; Manan, F.

2010-01-01

Background: Blood is man's complete and unchangeable identity. The ABO and Rh groups are recognised as major and clinically significant blood groups. Blood group antigens are not only important in relation to blood transfusion and organ transplantation, but also have been utilised in genetic research, anthropology and tracing ancestral relation of humans. The objective the present study is to examine the blood group antigens in infertile men for assessing the relationship to male infertility and to know the frequency of various blood groups among infertile males in our population. Method: A total of 1,521 patients along with 460 proven fathers as controls were recruited for the present study from both rural and urban areas of Pakistan and referred to Department of Reproductive Physiology/Health, Public Health Divisions, NIH, Islamabad, during 2002 to 2006. Blood grouping (ABO) and Rhesus factors (Rh) was done by the antigen antibody agglutination test. Results: Overall distribution of blood groups in the studied population of 1,521 subjects was 35.50%, 28.27%, 26.89% and 9.34% for blood groups O, B, A and AB respectively. The ratio of control to patient was 1:3.3. Conclusions: The present preliminary study revealed that in our population the prevalence of male infertility in blood group O is invariably higher than in all other ABO blood groups, showing a strong relationship between blood group O and male infertility. (author)

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

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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...

Cuticular chemistry of males and females in the ant Formica fusca

DEFF Research Database (Denmark)

Chernenko, Anton; Holman, Luke; Helanterä, Heikki

2012-01-01

in mediating recognition of society members and, thereby, allowing kin selection to operate. Here, we examined whether cuticular hydrocarbon profiles are sex-specific and whether males and young queens of the ant Formica fusca have colony-specific profiles. We also investigated whether there is a relationship...... between genetic relatedness and chemical diversity within colonies. We demonstrated that female and male sexuals do not have unique sex-specific compounds, but that there are quantitative chemical differences between the sexes. Out of the 51 cuticular hydrocarbon compounds identified, 10 showed...

Validation of an enzyme-immunoassay for the non-invasive monitoring of faecal testosterone metabolites in male cheetahs (Acinonyx jubatus).

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Pribbenow, Susanne; Wachter, Bettina; Ludwig, Carsten; Weigold, Annika; Dehnhard, Martin

2016-03-01

In mammals, the sex hormone testosterone is the major endocrine variable to objectify testicular activity and thus reproductive function in males. Testosterone is involved in the development and function of male reproductive physiology and sex-related behaviour. The development of a reliable androgen enzyme-immunoassay (EIA) to monitor faecal testosterone metabolites (fTM) is a powerful tool to non-invasively assess the gonadal status of males. We validated an epiandrosterone EIA for male cheetahs by performing a testosterone radiometabolism study followed by high-performance liquid chromatography (HPLC) analyses and excluding possible cross-reactivities with androgenic metabolites not derived from testosterone metabolism. The physiological and biological relevance of the epiandrosterone EIA was validated by demonstrating (1) a significant increase in fTM concentrations within one day in response to a testosterone injection, (2) a significant increase in fTM concentrations within one day in response to a gonadotropin-releasing hormone (GnRH) injection, which failed following a placebo injection, and (3) significant differences in fTM concentrations between adult male and adult female cheetahs and between adult and juvenile male cheetahs of a free-ranging population. Finally, we demonstrated stability of fTM concentrations measured in faecal samples exposed to ambient temperatures up to 72h. Our results clearly demonstrate that the epiandrosterone EIA is a reliable non-invasive method to monitor testicular activity in male cheetahs. Copyright © 2016 Elsevier Inc. All rights reserved.

Short-term enrichment makes male rats more attractive, more defensive and alters hypothalamic neurons.

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Rupshi Mitra

Full Text Available Innate behaviors are shaped by contingencies built during evolutionary history. On the other hand, environmental stimuli play a significant role in shaping behavior. In particular, a short period of environmental enrichment can enhance cognitive behavior, modify effects of stress on learned behaviors and induce brain plasticity. It is unclear if modulation by environment can extend to innate behaviors which are preserved by intense selection pressure. In the present report we investigate this issue by studying effects of relatively short (14-days environmental enrichment on two prominent innate behaviors in rats, avoidance of predator odors and ability of males to attract mates. We show that enrichment has strong effects on both the innate behaviors: a enriched males were more avoidant of a predator odor than non-enriched controls, and had a greater rise in corticosterone levels in response to the odor; and b had higher testosterone levels and were more attractive to females. Additionally, we demonstrate decrease in dendritic length of neurons of ventrolateral nucleus of hypothalamus, important for reproductive mate-choice and increase in the same in dorsomedial nucleus, important for defensive behavior. Thus, behavioral and hormonal observations provide evidence that a short period of environmental manipulation can alter innate behaviors, providing a good example of gene-environment interaction.

Energy metabolism and fasting in male and female insectivorous bats Molossus molossus (Chiroptera: Molossidae

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MB. Freitas

Full Text Available Metabolic adaptations induced by 24 and 48 hours of fasting were investigated in male and female insectivorous bats (Molossus molossus Pallas, 1766. For this purpose, plasma glucose, non esterified fatty acids (NEFA, glycogen, protein and lipids concentrations in liver and muscles were obtained. Data presented here demonstrate that fed bats showed plasma glucose levels similar to those reported for other mammal species. In response to fasting, glycemia was decreased only in 48 hours fasted females. Plasma NEFA levels were similar in both sexes, and did not exhibit any changes during fasting. Considering the data from energy reserve variations, fed females presented an increased content of liver glycogen as well as higher breast muscle protein and limbs lipids concentrations, compared to fed males. In response to fasting, liver and muscle glycogen levels remained unchanged. Considering protein and lipid reserves, only females showed decreased values following fasting, as seen in breast, limbs and carcass lipids and breast muscle protein reserves, but still fail to keep glucose homeostasis after 48 hours without food. Taken together, our data suggest that the energy metabolism of insectivorous bats may vary according to sexual differences, a pattern that might be associated to different reproduction investments and costs between genders.

Peculiarities of brain electric activity in young males and females of different creativity levels

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Ermakov, Pavel N.

2013-09-01

Full Text Available This article shows that the peculiarities of divergent and convergent thinking in young males and females of various creativity levels are stipulated by a definite EEG frequency-and-spatial arrangement. Young males and females of mixed and left lateral arrangement profiles demonstrate an expressed activity of occipital, central, and temporal areas of both cerebral hemispheres. In young males and females of right LAP (lateral arrangement profile, connections are clearly localized in case of solution of both convergent and divergent tasks. Solution of divergent and convergent tasks may condition certain frequency-and-spatial arrangement of EEG in young males and females with different levels of academic progress and a different lateral arrangement profile (LAP.

American Higher Education and Income Inequality

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Hill, Catharine B.

2016-01-01

This paper demonstrates that increasing income inequality can contribute to the trends we see in American higher education, particularly in the selective, private nonprofit and public sectors. Given these institutions' selective admissions and commitment to socioeconomic diversity, the paper demonstrates how increasing income inequality leads to…

Development of the rate of employment and unemployment of males and females in ten associated countries of EU

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Jan Klíma

2004-01-01

Full Text Available The paper is focused on the evaluation the rates of employment and unemployment of women, men and as a whole in ten associated countries of EU. Rates of employment were evaluated in the period 1996-2002. Rates of unemployment were evaluated in the period 1996-2003. Employment of males in all ten associated countries of EU is higher then employment of females. Unemployment of females in the Czech Republic, Cyprus, Malta, Poland, Slovakia and Slovenia is higher than unemployment of males and in opposite unemployment of females in Estonia, Hungary, Lithuania and Latvia is lower than unemployment of males. Trends of rates of male, female and total employment and unemployment are evaluated. Methods of regression and correlation analysis, development trends and cluster analysis were applied for the mathematical-statistical analysis.

Splenectomy reduces infarct volume and neuroinflammation in male but not female mice in experimental stroke

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Dotson, Abby L.; Wang, Jianming; Saugstad, Julie; Murphy, Stephanie J.; Offner, Halina

2014-01-01

The peripheral immune response contributes to neurodegeneration after stroke yet little is known about how this process differs between males and females. The current study demonstrates that splenectomy prior to experimental stroke eliminates sex differences in infarct volume and activated brain monocytes/microglia. In the periphery of both sexes, activated T cells correlate directly with stroke outcome while monocytes are reduced by splenectomy only in males. This study provides new information about the sex specific mechanisms of the peripheral immune response in neurodegeneration after stroke and demonstrates the need for representation of both sexes in basic and clinical stroke research. PMID:25434281

Confirmatory factor analysis of the Drive for Muscularity Scale-S (DMS-S) and Male Body Attitudes Scale-S (MBAS-S) among male university students in Buenos Aires.

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Compte, Emilio J; Sepúlveda, Ana R; de Pellegrin, Yolanda; Blanco, Miriam

2015-06-01

Several studies have demonstrated that men express body dissatisfaction differently than women. Although specific instruments that address body dissatisfaction in men have been developed, only a few have been validated in Latin-American male populations. The aim of this study was to reassess the factor structure of the Spanish versions of the Drive for Muscularity Scale (DMS-S) and the Male Body Attitudes Scale (MBAS-S) in an Argentinian sample. A cross-sectional study was conducted among 423 male students to examine: the factorial structure (confirmatory factor analysis), the internal consistency reliability, and the concurrent, convergent and discriminant validity of both scales. Results replicated the two factor structures for the DMS-S and MBAS-S. Both scales showed excellent levels of internal consistency, and various measures of construct validity indicated that the DMS-S and MBAS-S were acceptable and valid instruments to assess body dissatisfaction in Argentinian males. Copyright © 2015 Elsevier Ltd. All rights reserved.

Social Network Misuse in the Classroom and Its Impact on Male Student Motivation in UAE Tertiary Education

OpenAIRE

Sultan A. Alkaabi; Peter Albion; Petrea Redmond

2017-01-01

This paper presents data obtained from focus groups conducted to investigate male students’ experiences in higher education in the United Arab Emirates. Among the issues discussed by students was the impact of social networks addiction on student motivation and this paper focuses on that issue. Thirteen focus groups were conducted with 83 English as a Foreign Language male students at four government campuses including United Arab Emirates University at Al Ain Campus, Higher College of Techno...

An International Comparison of Female and Male Students' Attitudes to the Use of Animals

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Phillips, Clive; Izmirli, Serdar; Aldavood, Javid; Alonso, Marta; Choe, Bi; Hanlon, Alison; Handziska, Anastasija; Illmann, Gudrun; Keeling, Linda; Kennedy, Mark; Lee, Gwi; Lund, Vonne; Mejdell, Cecilie; Pelagic, Veselinas; Rehn, Therese

2011-01-01

Simple Summary We surveyed university students in 11 Eurasian countries for their attitudes to animals, using an internet-based questionnaire to which 1,902 female and 1,530 male student responded from 102 universities. Across countries female students had greater concern for animal welfare and rights than males, but especially so in more gender empowered countries. One contributing factor appeared to be the greater association of females than males with pets, and a possible outcome was greater female avoidance of meat consumption, especially red meat. Abstract Previous research has demonstrated that in households where the male partner is more dominant, there is convergence in male and female attitudes towards animals, whereas if the female partner is empowered they exhibit greater empathy towards animals than the male partner. We tested this theory of ‘female empowered empathy’ internationally in a survey of female and male students' attitudes towards use of animals, conducted in 11 Eurasian countries: China, Czech Republic, Great Britain, Iran, Ireland, South Korea, Macedonia, Norway, Serbia, Spain and Sweden. Gender empowerment was estimated for each country using the Gender Empowerment Measure designed by the United Nations. The survey was administered via the internet in universities within countries, and 1,902 female and 1,530 male student responses from 102 universities were received. Respondents rated the acceptability of 43 major concerns about human use of animals, and the importance of 13 world social issues, including animal protection, environmental protection and sustainable development. Females had greater concern for animal welfare and rights than males. There was a positive correlation between the Gender Empowerment Measure and the ratio of female to male concern for animal welfare and rights, but not for other world issues. Thus in countries where females were more empowered, principally Sweden, Norway and Great Britain, females had much

The Gender Difference of Peer Influence in Higher Education

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Han, Li; Li, Tao

2009-01-01

Investigations of the existence of residential peer effects in higher education has shown mixed results. Using data from a Chinese college, we find no evidence of robust residential peer effects. Using the same data we find evidence that females respond to peer influences, whereas males do not, consistent with social psychology theories that…

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.

Klinefelter syndrome and its association with male infertility

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V Ramakrishnan

2014-03-01

Full Text Available Klinefelter's syndrome is the most common genetic disorder in which there is at least one extra X chromosome. Males normally have an X chromosome and a Y chromosome (XY. But males who have Klinefelter syndrome have an extra X chromosome (XXY, giving them a total of 47 instead of the normal 46 chromosomes. Sex chromosome abnormalities are more frequently associated with male infertility. The prevalence of XXYs has risen from 1.09 to 1.72 per 1 000 male births. A patient attended to fertility and genetic clinic, during the clinical diagnosis we found the following complaints of loss of secondary sexual characteristics and infertility. Physical examination revealed breast development, thin built, small size testes, and absence of beard and pubic hairs. Karyotype and biochemical analysis were performed to detect chromosomal abnormality as well as hormonal level to confirm the diagnosis of Klinefelter's syndrome. Chromosomal analysis of the peripheral blood lymphocytes demonstrated the constitutional karyotype of 47, XXY. Using karyotype the presence of extra X chromosome was confirmed, supporting the cytogenetic finding. The 47, XXY syndrome is relatively uncommon and can be missed clinically because of its variable clinical presentations. Accurate diagnosis of this constitutional karyotype provides a valuable aid in the counselling and early management of the patients who undertake fertility evaluation.

SHANK1 Deletions in Males with Autism Spectrum Disorder.

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Sato, Daisuke; Lionel, Anath C; Leblond, Claire S; Prasad, Aparna; Pinto, Dalila; Walker, Susan; O'Connor, Irene; Russell, Carolyn; Drmic, Irene E; Hamdan, Fadi F; Michaud, Jacques L; Endris, Volker; Roeth, Ralph; Delorme, Richard; Huguet, Guillaume; Leboyer, Marion; Rastam, Maria; Gillberg, Christopher; Lathrop, Mark; Stavropoulos, Dimitri J; Anagnostou, Evdokia; Weksberg, Rosanna; Fombonne, Eric; Zwaigenbaum, Lonnie; Fernandez, Bridget A; Roberts, Wendy; Rappold, Gudrun A; Marshall, Christian R; Bourgeron, Thomas; Szatmari, Peter; Scherer, Stephen W

2012-05-04

Recent studies have highlighted the involvement of rare (number variations and point mutations in the genetic etiology of autism spectrum disorder (ASD); these variants particularly affect genes involved in the neuronal synaptic complex. The SHANK gene family consists of three members (SHANK1, SHANK2, and SHANK3), which encode scaffolding proteins required for the proper formation and function of neuronal synapses. Although SHANK2 and SHANK3 mutations have been implicated in ASD and intellectual disability, the involvement of SHANK1 is unknown. Here, we assess microarray data from 1,158 Canadian and 456 European individuals with ASD to discover microdeletions at the SHANK1 locus on chromosome 19. We identify a hemizygous SHANK1 deletion that segregates in a four-generation family in which male carriers--but not female carriers--have ASD with higher functioning. A de novo SHANK1 deletion was also detected in an unrelated male individual with ASD with higher functioning, and no equivalent SHANK1 mutations were found in >15,000 controls (p = 0.009). The discovery of apparent reduced penetrance of ASD in females bearing inherited autosomal SHANK1 deletions provides a possible contributory model for the male gender bias in autism. The data are also informative for clinical-genetics interpretations of both inherited and sporadic forms of ASD involving SHANK1. Copyright © 2012 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Estradiol increases choice of cocaine over food in male rats.

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Bagley, Jared R; Adams, Julia; Bozadjian, Rachel V; Bubalo, Lana; Ploense, Kyle L; Kippin, Tod E

2017-10-19

Estradiol modulates the rewarding and reinforcing properties of cocaine in females, including an increase in selection of cocaine over alternative reinforcers. However, the effects of estradiol on male cocaine self-administration behavior are less studied despite equivalent levels of estradiol in the brains of adult males and females, estradiol effects on motivated behaviors in males that share underlying neural substrates with cocaine reinforcement as well as expression of estrogen receptors in the male brain. Therefore, we sought to characterize the effects of estradiol in males on choice between concurrently-available cocaine and food reinforcement as well as responding for cocaine or food in isolation. Male castrated rats (n=46) were treated daily with estradiol benzoate (EB) (5μg/0.1, S.C.) or vehicle (peanut oil) throughout operant acquisition of cocaine (1mg/kg, IV; FI20 sec) and food (3×45mg; FI20 sec) responding, choice during concurrent access and cocaine and food reinforcement under progressive ratio (PR) schedules. EB increased cocaine choice, both in terms of percent of trials on which cocaine was selected and the proportion of rats exhibiting a cocaine preference as well as increased cocaine, but not food, intake under PR. Additionally, within the EB treated group, cocaine-preferring rats exhibited enhanced acquisition of cocaine, but not food, reinforcement whereas no acquisition differences were observed across preferences in the vehicle treated group. These findings demonstrate that estradiol increases cocaine choice in males similarly to what is observed in females. Copyright © 2017 Elsevier Inc. All rights reserved.

Gender/ed Discourses and Emotional Sub-Texts: Theorising Emotion in UK Higher Education

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Leathwood, Carole; Hey, Valerie

2009-01-01

This article engages with contemporary debates about the absence/presence of emotion in higher education. UK higher education has traditionally been constructed as an emotion-free zone, reflecting the dominance of Cartesian dualism with its rational/emotional, mind/body, male/female split. This construction has been challenged in recent years by…

Variations in physical activity of male and female students from the Ukraine in health-promoting life style

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Józef Bergier

2017-05-01

Females more than males demonstrated lower indices of participation in physical activity, which did not permit the formulation of a positive assessment of their lifestyle. A positive phenomenon is the normal BMI and trace values of overweight in women, exactly the reverse to males.

Think Crisis-Think Female : The Glass Cliff and Contextual Variation in the Think Manager-Think Male Stereotype

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Ryan, Michelle K.; Haslam, S. Alexander; Hersby, Mette D.; Bongiorno, Renata

The "think manager think male" (TMTM) association underlies many gender inequalities in the workplace. However, research into the "glass cliff" has demonstrated that the suitability of male and female managers varies as a function of company performance such that in times of poor performance people

Case study: a young male with auditory hallucinations in paranoid schizophrenia.

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Kotowski, Abigail

2012-02-01

The purpose of this case study is to demonstrate use of the nursing process and the standardized nursing languages of NANDA International (NANDA-I), the Nursing Outcomes Classification (NOC), and the Nursing Interventions Classification (NIC) to assist a young male with paranoid schizophrenia to deal with auditory hallucinations. Data were obtained from the experience and expertise of the author and published literature. This case study demonstrates nurses' clinical decision making in providing care for an adolescent with mental illness. This case study provides the pertinent nursing diagnosis, patient outcomes, and nursing interventions for a young male with auditory hallucinations in paranoid schizophrenia. The use of NANDA-I, NOC, and NIC can provide the necessary framework for enhancing and improving the management of care with patients who experience auditory hallucinations in paranoid schizophrenia. © 2011, The Authors. International Journal of Nursing Terminologies and Classifications © 2011, NANDA International.

KATNAL1 regulation of sertoli cell microtubule dynamics is essential for spermiogenesis and male fertility.

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Lee B Smith

Full Text Available Spermatogenesis is a complex process reliant upon interactions between germ cells (GC and supporting somatic cells. Testicular Sertoli cells (SC support GCs during maturation through physical attachment, the provision of nutrients, and protection from immunological attack. This role is facilitated by an active cytoskeleton of parallel microtubule arrays that permit transport of nutrients to GCs, as well as translocation of spermatids through the seminiferous epithelium during maturation. It is well established that chemical perturbation of SC microtubule remodelling leads to premature GC exfoliation demonstrating that microtubule remodelling is an essential component of male fertility, yet the genes responsible for this process remain unknown. Using a random ENU mutagenesis approach, we have identified a novel mouse line displaying male-specific infertility, due to a point mutation in the highly conserved ATPase domain of the novel KATANIN p60-related microtubule severing protein Katanin p60 subunit A-like1 (KATNAL1. We demonstrate that Katnal1 is expressed in testicular Sertoli cells (SC from 15.5 days post-coitum (dpc and that, consistent with chemical disruption models, loss of function of KATNAL1 leads to male-specific infertility through disruption of SC microtubule dynamics and premature exfoliation of spermatids from the seminiferous epithelium. The identification of KATNAL1 as an essential regulator of male fertility provides a significant novel entry point into advancing our understanding of how SC microtubule dynamics promotes male fertility. Such information will have resonance both for future treatment of male fertility and the development of non-hormonal male contraceptives.

TRADISI LISAN MALE-MALE: NYANYIAN KEMATIAN DALAM MASYARAKAT CIACIA: KAJIAN SOSIOLOGIS DAN UPAYA PEWARISAN

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Asrif Asrif

2016-08-01

  Oral Tradition of Male-Male: Death Anthem Ciacia: Sosiological Studies and an Effort to Pass It On to the next Generation. Male-Male is lyrics sung upon the death of a member of the society who is considered a perfect person. This oral tradition shows the society appreciation towards the person through the expression of sadness, longing, partience and praises. Male-Male serves various functions; both private functions (the singer and host, and societal function (the guests. For th singer and the host, this tradition serves as consolation, caring towards other members, dissemination of social values and religion, prestige, and passing on a tradition. For the society, Male-Male functions as a self remainder of death, strengthening faith, increasing empathy and solidarity. Efforts to guarantee the continuity of this tradition by the next generation are required. Formal effortcan be made through schools, and the informal ones can be made through the strengthening of tradition bodies. Keywords: Oral tradition, Male-Male, Sociology, and Passing the tradition

Systemic lupus erythematosus in Spanish males: a study of the Spanish Rheumatology Society Lupus Registry (RELESSER) cohort.

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Riveros Frutos, A; Casas, I; Rúa-Figueroa, I; López-Longo, F J; Calvo-Alén, J; Galindo, M; Fernández-Nebro, A; Pego-Reigosa, J M; Olivé Marqués, A

2017-06-01

Objective The objective of this study was to describe the demographic, clinical, and immunological manifestations of systemic lupus erythematosus (SLE) in male patients. Methods A cross-sectional, multicenter study was carried out of 3651 patients (353 men, 9.7%, and 3298 women, 90.2%) diagnosed with SLE, included in the Spanish Rheumatology Society SLE Registry (RELESSER). Results Mean ages (18-92 years) of symptom onset were 37 (SD 17) years (men) and 32 (SD 14) years (women). Male/female ratio was 1/9. Age of onset of symptoms and age at diagnosis were higher in men than in women ( p lupus nephritis was more common in men, being present in 155 (44.8%) of males versus 933 (29%) of females ( p  50 years had a higher mortality (odds ratios 3.6 and 2.1, respectively). Furthermore, SLE patients who developed pulmonary hemorrhage, pulmonary hypertension, psychiatric involvement, complement deficiency, and hemophagocytic syndrome also had higher mortality, regardless of gender. Conclusion Patients with SLE over the age of 50 years have an increased risk of mortality. In Caucasians, age at diagnosis and symptom onset is higher in men than in women. The diagnostic delay is shorter in men. Male SLE patients present more cardiovascular comorbidities, and also more serositis, adenopathies, splenomegaly, renal involvement, convulsion, thrombosis, and lupus anticoagulant positivity than women.

Low self-esteem and positive beliefs about smoking: a destructive combination for male college students.

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Hale, Willie J; Perrotte, Jessica K; Baumann, Michael R; Garza, Raymond T

2015-07-01

Men exhibit higher rates of smoking relative to women (CDC, 2014). Given the associated health and socio-economic consequences, it would be valuable to explore the psychological factors underlying this variance. We contend that positive beliefs about smoking influence this difference, and that self-esteem moderates these beliefs. As part of a multi-institutional collaborative study funded by the American Legacy Foundation, 445 participants who reported being either steady or occasional smokers completed a series of questionnaires assessing their beliefs and behaviors involving smoking as well as several dispositional variables. Moderated mediation was used to test for conditional indirect effects. The total, indirect, and direct effects of gender were significant for individuals with lower, but not higher self-esteem. Males with lower self-esteem exhibited more positive beliefs and smoking behavior than females with lower self-esteem. No differences between males and females with higher self-esteem were observed. The gender gap in smoking behavior appears to occur primarily among individuals with lower self-esteem. It is a particularly detrimental risk factor for males, as it is related to higher positive views about smoking and increased tobacco consumption. These results highlight the importance of developing multifaceted gender specific belief-based preventative interventions to address smoking related behaviors. Copyright © 2015. Published by Elsevier Ltd.

Inhibition of Estradiol Synthesis Impairs Fear Extinction in Male Rats

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Graham, Bronwyn M.; Milad, Mohammed R.

2014-01-01

Emerging research has demonstrated that the sex hormone estradiol regulates fear extinction in female rodents and women. Estradiol may also regulate fear extinction in males, given its role in synaptic plasticity in both sexes. Here we report that inhibition of estradiol synthesis during extinction training, via the aromatase inhibitor fadrozole,…

Men and masculinities in forensic psychiatric care: an interview study concerning male nurses' experiences of working with male caregivers and male patients.

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Kumpula, Esa; Ekstrand, Per

2009-09-01

Forensic psychiatric care is largely populated by men--as patients, caregivers, and nurses. Previous research has not focused on the meaning of gender in this context. The aim of this study is to analyse male nurses' experiences of working with male caregivers and attending to male patients in forensic psychiatric care. Data were collected through interviews with six male nurses. The results consist of five themes. Protection and defence are key aspects of care and male caregivers gain status and authority through their physical strength. This could hamper caring and provide male caregivers with a superior position in the department.

Adult Arabs have higher risk for diabetes mellitus than Jews in Israel.

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Jaffe, Anat; Giveon, Shmuel; Wulffhart, Liat; Oberman, Bernice; Baidousi, Maslama; Ziv, Arnona; Kalter-Leibovici, Ofra

2017-01-01

Diabetes mellitus is an emerging epidemic in the Arab world. Although high diabetes prevalence is documented in Israeli Arabs, information from cohort studies is scant. This is a population study, based on information derived between 2007-2011, from the electronic database of the largest health fund in Israel, among Arabs and Jews. Prevalence, 4-year-incidence and diabetes hazard ratios [HRs], adjusted for sex and the metabolic-syndrome [MetS]-components, were determined in 3 age groups (Arabs (males: 49%, age: 39.4±17.3) and 16,012 Jews (males: 50%, age: 40.5 ±17.6). The overall age and sex-adjusted diabetes prevalence rates were much higher among Arabs 18.4% (95%CI: 17.6-19.1); and 10.3% (95%CI: 9.7-10.9) among Jews. Arab females had higher prevalence rates 20.0% (95%CI: 19-21) than Arab males 16.7% (95%CI: 15.7-17.8). Annual incidence rates were also significantly higher among Arabs 2.9% (95%CI: 2.7-3.1) than among Jews 1.7% (95%CI: 1.6-1.8). This held true across all age and sex subgroups. Adjustment for body mass index [BMI] attenuated HR estimates associated with Arab ethnicity across all age subgroups, mainly in the Arabs than Jews. Males, however, did not differ by ethnicity. Arabs, mainly female, have high incidence and prevalence of diabetes. This excess risk is only partially explained by the high prevalence of obesity. Effective culturally-congruent diabetes prevention and treatment and an effective engagement partnership with the Arab community are of paramount need.

Cortical activation during mental rotation in male-to-female and female-to-male transsexuals under hormonal treatment.

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Carrillo, Beatriz; Gómez-Gil, Esther; Rametti, Giuseppina; Junque, Carme; Gomez, Angel; Karadi, Kazmer; Segovia, Santiago; Guillamon, Antonio

2010-09-01

There is strong evidence of sex differences in mental rotation tasks. Transsexualism is an extreme gender identity disorder in which individuals seek cross-gender treatment to change their sex. The aim of our study was to investigate if male-to-female (MF) and female-to-male (FM) transsexuals receiving cross-sex hormonal treatment have different patterns of cortical activation during a three-dimensional (3D) mental rotation task. An fMRI study was performed using a 3-T scan in a sample of 18 MF and 19 FM under chronic cross-sex hormonal treatment. Twenty-three males and 19 females served as controls. The general pattern of cerebral activation seen while visualizing the rotated and non-rotated figures was similar for all four groups showing strong occipito-parieto-frontal brain activation. However, compared to control males, the activation of MF transsexuals during the task was lower in the superior parietal lobe. Compared to control females, MF transsexuals showed higher activation in orbital and right dorsolateral prefrontal regions and lower activation in the left prefrontal gyrus. FM transsexuals did not differ from either the MF transsexual or control groups. Regression analyses between cerebral activation and the number of months of hormonal treatment showed a significant negative correlation in parietal, occipital and temporal regions in the MF transsexuals. No significant correlations with time were seen in the FM transsexuals. In conclusion, although we did not find a specific pattern of cerebral activation in the FM transsexuals, we have identified a specific pattern of cerebral activation during a mental 3D rotation task in MF transsexuals under cross-sex hormonal treatment that differed from control males in the parietal region and from control females in the orbital prefrontal region. The hypoactivation in MF transsexuals in the parietal region could be due to the hormonal treatment or could reflect a priori cerebral differences between MF transsexual

Costs of female odour in males of the parasitic wasp Lariophagus distinguendus (Hymenoptera: Pteromalidae)

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Ruther, Joachim; Steiner, Sven

2008-06-01

The display of female traits by males is widespread in the animal kingdom. In several species, this phenomenon has been shown to function adaptively as a male mating strategy to deceive sexual rivals (female mimicry). Freshly emerged males of the parasitic wasp Lariophagus distinguendus (Hymenoptera: Pteromalidae) are perceived by other males as if they were females because of a very similar composition of cuticular hydrocarbons which function as a sex pheromone in this species inducing courtship behaviour in males. Within 32 h, however, males deactivate the pheromone and are no longer courted by other males. In this paper, behavioural experiments were performed to test hypotheses on potential costs and benefits associated with the female odour in young males. We did not find any benefits, but demonstrated that young males were significantly more often outrivaled in male-male contests when competing with two older males for a female. Also, young males were significantly more often mounted in homosexual courtship events during these contests. Thus, display of female traits by males is not necessarily beneficial, and in fact, can be disadvantageous. We suggest that these costs have favoured the evolution of the pheromone deactivation mechanism in L. distinguendus males. The function of cuticular hydrocarbons as a female courtship pheromone in L. distinguendus might have evolved secondarily from a primary function relevant for both genders, and the deactivation of the signal in males might have caused a shift of specificity of the chemical signal from the species level to the sex level.

Female penis, male vagina, and their correlated evolution in a cave insect.

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Yoshizawa, Kazunori; Ferreira, Rodrigo L; Kamimura, Yoshitaka; Lienhard, Charles

2014-05-05

Sex-specific elaborations are common in animals and have attracted the attention of many biologists, including Darwin [1]. It is accepted that sexual selection promotes the evolution of sex-specific elaborations. Due to the faster replenishment rate of gametes, males generally have higher potential reproductive and optimal mating rates than females. Therefore, sexual selection acts strongly on males [2], leading to the rapid evolution and diversification of male genitalia [3]. Male genitalia are sometimes used as devices for coercive holding of females as a result of sexual conflict over mating [4, 5]. In contrast, female genitalia are usually simple. Here we report the reversal of intromittent organs in the insect genus Neotrogla (Psocodea: Prionoglarididae) from Brazilian caves. Females have a highly elaborate, penis-like structure, the gynosome, while males lack an intromittent organ. The gynosome has species-specific elaborations, such as numerous spines that fit species-specific pouches in the simple male genital chamber. During prolonged copulation (~40-70 hr), a large and potentially nutritious ejaculate is transferred from the male via the gynosome. The correlated genital evolution in Neotrogla is probably driven by reversed sexual selection with females competing for seminal gifts. Nothing similar is known among sex-role reversed animals. Copyright © 2014 Elsevier Ltd. All rights reserved.

Radiologically revealed spine osteoporosis in male with hypertension and coronary heart disease

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P A Chizhov

2005-01-01

Full Text Available Radiologically revealed spine osteoporosis in male with hypertension and coronary heart disease Objective. To study prevalence and intensity of spine osteoporosis (OP in men suffering from hypertension (H and coronary heart disease (CHD. Material and methods. 101 men with H and CHD aged 50 to 78 years (mean age 60,6±0,85 years and 37 men of control group without cardiovascular diseases aged 50-66 years (mean age 58,6±0,74 years were examined. Clinical examination, radiological, radiomorphometric spine examination and echocardioscopy were performed. Results. OP was revealed in 34,65% of main group pts what is 3,2 times more frequent than in control group (10,8%, p<0,05. OP intensity in men with H and CHD was significantly higher than in healthy people. Vfertebral fractures were revealed in 12,87+3,3% of main group pts and only in 2,7±2,7% in control group (p<0,05. OP development dependence from cardiac history duration and cardiac pathology severity was demonstrated. Conclusion. The results of the study show significantly higher prevalence of spine OP among men suffering from H and CHD. Long history and severity of cardiovascular pathology clinical signs promote OP frequency and severity increase.

Lead exposure in adult males in urban Transvaal Province, South Africa during the apartheid era.

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Hess, Catherine A; Cooper, Matthew J; Smith, Martin J; Trueman, Clive N; Schutkowski, Holger

2013-01-01

Human exposure to lead is a substantial public health hazard worldwide and is particularly problematic in the Republic of South Africa given the country's late cessation of leaded petrol. Lead exposure is associated with a number of serious health issues and diseases including developmental and cognitive deficiency, hypertension and heart disease. Understanding the distribution of lifetime lead burden within a given population is critical for reducing exposure rates. Femoral bone from 101 deceased adult males living in urban Transvaal Province (now Gauteng Province), South Africa between 1960 and 1998 were analyzed for lead concentration by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Of the 72 black and 29 white individuals sampled, chronic lead exposure was apparent in nearly all individuals. White males showed significantly higher median bone lead concentration (ME = 10.04 µg·g(-1)), than black males (ME = 3.80 µg·g(-1)) despite higher socioeconomic status. Bone lead concentration covaries significantly, though weakly, with individual age. There was no significant temporal trend in bone lead concentration. These results indicate that long-term low to moderate lead exposure is the historical norm among South African males. Unexpectedly, this research indicates that white males in the sample population were more highly exposed to lead.

Comparative Transcriptomes Profiling of Photoperiod-sensitive Male Sterile Rice Nongken 58S During the Male Sterility Transition between Short-day and Long-day

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Zhu Yingguo

2011-09-01

Full Text Available Abstract Background Photoperiod-sensitive genic male sterile (PGMS rice, Nongken 58S, was discovered in 1973. It has been widely used for the production of hybrid rice, and great achievements have been made in improving rice yields. However, the mechanism of the male sterility transition in PGMS rice remains to be determined. Results To investigate the transcriptome during the male sterility transition in PGMS rice, the transcriptome of Nongken 58S under short-day (SD and long-day (LD at the glume primordium differentiation and pistil/stamen primordium forming stages was compared. Seventy-three and 128 differentially expressed genes (DEGs were identified at the glume primordium differentiation and pistil/stamen primordium forming stages, respectively. Five and 22 genes were markedly up-regulated (≥ 5-fold, and two and five genes were considerably down-regulated (≥ 5-fold under SD during the male sterility transition. Gene ontology annotation and pathway analysis revealed that four biological processes and the circadian rhythms and the flowering pathways coordinately regulated the male sterility transition. Further quantitative PCR analysis demonstrated that the circadian rhythms of OsPRR1, OsPRR37, OsGI, Hd1, OsLHY and OsDof in leaves were obviously different between Nongken 58S and Nongken 58 under LD conditions. Moreover, both OsPRR37 and Hd1 in the inflorescence displayed differences between Nongken 58S and Nongken 58 under both LD and SD conditions. Conclusion The results presented here indicate that the transcriptome in Nongken 58S was significantly suppressed under LD conditions. Among these DEGs, the circadian rhythm and the flowering pathway were involved in the male sterility transition. Furthermore, these pathways were coordinately involved in the male sterility transition in PGMS rice.

Paternal cocaine taking elicits epigenetic remodeling and memory deficits in male progeny.

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Wimmer, M E; Briand, L A; Fant, B; Guercio, L A; Arreola, A C; Schmidt, H D; Sidoli, S; Han, Y; Garcia, B A; Pierce, R C

2017-11-01

Paternal environmental perturbations including exposure to drugs of abuse can produce profound effects on the physiology and behavior of offspring via epigenetic modifications. Here we show that adult drug-naive male offspring of cocaine-exposed sires have memory formation deficits and associated reductions in NMDA receptor-mediated hippocampal synaptic plasticity. Reduced levels of the endogenous NMDA receptor co-agonist d-serine were accompanied by increased expression of the d-serine degrading enzyme d-amino acid oxidase (Dao1) in the hippocampus of cocaine-sired male progeny. Increased Dao1 transcription was associated with enrichment of permissive epigenetic marks on histone proteins in the hippocampus of male cocaine-sired progeny, some of which were enhanced near the Dao1 locus. Finally, hippocampal administration of d-serine reversed both the memory formation and synaptic plasticity deficits. Collectively, these results demonstrate that paternal cocaine exposure produces epigenetic remodeling in the hippocampus leading to NMDA receptor-dependent memory formation and synaptic plasticity impairments only in male progeny, which has significant implications for the male descendants of chronic cocaine users.

De novo-based transcriptome profiling of male-sterile and fertile watermelon lines.

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Rhee, Sun-Ju; Kwon, Taehyung; Seo, Minseok; Jang, Yoon Jeong; Sim, Tae Yong; Cho, Seoae; Han, Sang-Wook; Lee, Gung Pyo

2017-01-01

The whole-genome sequence of watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai), a valuable horticultural crop worldwide, was released in 2013. Here, we compared a de novo-based approach (DBA) to a reference-based approach (RBA) using RNA-seq data, to aid in efforts to improve the annotation of the watermelon reference genome and to obtain biological insight into male-sterility in watermelon. We applied these techniques to available data from two watermelon lines: the male-sterile line DAH3615-MS and the male-fertile line DAH3615. Using DBA, we newly annotated 855 watermelon transcripts, and found gene functional clusters predicted to be related to stimulus responses, nucleic acid binding, transmembrane transport, homeostasis, and Golgi/vesicles. Among the DBA-annotated transcripts, 138 de novo-exclusive differentially-expressed genes (DEDEGs) related to male sterility were detected. Out of 33 randomly selected newly annotated transcripts and DEDEGs, 32 were validated by RT-qPCR. This study demonstrates the usefulness and reliability of the de novo transcriptome assembly in watermelon, and provides new insights for researchers exploring transcriptional blueprints with regard to the male sterility.

Canine tooth size and fitness in male mandrills (Mandrillus sphinx).

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Leigh, Steven R; Setchell, Joanna M; Charpentier, Marie; Knapp, Leslie A; Wickings, E Jean

2008-07-01

Sexual selection theory explains the evolution of exaggerated male morphologies and weaponry, but the fitness consequences of developmental and age-related changes in these features remain poorly understood. This long-term study of mandrill monkeys (Mandrillus sphinx) demonstrates how age-related changes in canine tooth weaponry and adult canine size correlate closely with male lifetime reproductive success. Combining long-term demographic and morphometric data reveals that male fitness covaries simply and directly with canine ontogeny, adult maximum size, and wear. However, fitness is largely independent of other somatometrics. Male mandrills sire offspring almost exclusively when their canines exceed approximately 30 mm, or two-thirds of average adult value (45 mm). Moreover, sires have larger canines than nonsires. The tooth diminishes through wear as animals age, corresponding with, and perhaps influencing, reproductive senescence. These factors combine to constrain male reproductive opportunities to a brief timespan, defined by the period of maximum canine length. Sexually-selected weaponry, especially when it is nonrenewable like the primate canine tooth, is intimately tied to the male life course. Our analyses of this extremely dimorphic species indicate that sexual selection is closely intertwined with growth, development, and aging, pointing to new directions for sexual selection theory. Moreover, the primate canine tooth has potential as a simple mammalian system for testing genetically-based models of aging. Finally, the tooth may record details of life histories in fossil primates, especially when sexual selection has played a role in the evolution of dimorphism.

The impact of Wolbachia, male age and mating history on cytoplasmic incompatibility and sperm transfer in Drosophila simulans.